Absence of a dose-fractionation effect on neoplastic transformation induced by fission-spectrum neutrons in C3H 10T1/2 cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Saran, A.; Pazzaglia, S.; Coppola, M.

1991-06-01

We have investigated the effect of fission-spectrum neutron dose fractionation on neoplastic transformation of exponentially growing C3H 10T1/2 cells. Total doses of 10.8, 27, 54, and 108 cGy were given in single doses or in five equal fractions delivered at 24-h intervals in the biological channel of the RSV-TAPIRO reactor at CRE-Casaccia. Both cell inactivation and neoplastic transformation were more effectively induced by fission neutrons than by 250-kVp X rays. No significant effect on cell survival or neoplastic transformation was observed with split doses compared to single doses of fission-spectrum neutrons. Neutron RBE values relative to X rays determined frommore » data for survival and neoplastic transformation were comparable.« less

Relative contributions of the fraction of unfrozen water and of salt concentration to the survival of slowly frozen human erythrocytes.

PubMed Central

Mazur, P; Rall, W F; Rigopoulos, N

1981-01-01

As suspensions of cells freeze, the electrolytes and other solutes in the external solution concentrate progressively, and the cells undergo osmotic dehydration if cooling is slow. The progressive concentration of solute comes about as increasing amounts of pure ice precipitate out of solution and cause the liquid-filled channels in which the cells are sequestered to dwindle in size. The consensus has been that slow freezing injury is related to the composition of the solution in these channels and not to the amount of residual liquid. The purpose of the research reported here was to test this assumption on human erythrocytes. Ordinarily, solute concentration and the amount of liquid in the unfrozen channels are inversely coupled. To vary them independently, one must vary the initial solute concentration. Two solutes were used here: NaCl and the permeating protective additive glycerol. To vary the total initial solute concentration while holding the mass ratio of glycerol to NaCl constant, we had to allow the NaCl tonicity to depart from isotonic. Specifically, human red cells were suspended in solutions with weight ratios of glycerol to NaCl of either 5.42 or 11.26, where the concentrations of NaCl were 0.6, 0.75, 1.0, 2.0, 3.0, or 4.0 times isotonic. Samples were then frozen to various subzero temperatures, which were chosen to produce various molalities of NaCl (0.24-3.30) while holding the fraction of unfrozen water constant, or conversely to produce various unfrozen fractions (0.03-0.5) while holding the molality of salt constant. (Not all combinations of these values were possible). The following general findings emerged: (a) few cells survived the freezing of greater than 90% of the extracellular water regardless of the salt concentration in the residual unfrozen portion. (b) When the fraction of frozen water was less than 75% the majority of the cells survived even when the salt concentration in the unfrozen portion exceeded 2 molal. (c) Salt concentration affected survival significantly only when the frozen fraction lay between 75 and 90%. To find a major effect on survival of the fraction of water that remains unfrozen was unexpected. It may require major modifications in how cryobiologists view solution-effect injury and its prevention. PMID:7326328

KPU-300, a Novel Benzophenone–Diketopiperazine–Type Anti-Microtubule Agent with a 2-Pyridyl Structure, Is a Potent Radiosensitizer That Synchronizes the Cell Cycle in Early M Phase

PubMed Central

Okuyama, Kohei; Kaida, Atsushi; Hayashi, Yoshiki; Hayashi, Yoshio; Harada, Kiyoshi; Miura, Masahiko

2015-01-01

KPU-300 is a novel colchicine-type anti-microtubule agent derived from plinabulin (NPI-2358). We characterized the effects of KPU-300 on cell cycle kinetics and radiosensitization using HeLa cells expressing the fluorescent ubiquitination-based cell cycle indicator (Fucci). Cells treated with 30 nM KPU-300 for 24 h were efficiently synchronized in M phase and contained clearly detectable abnormal Fucci fluorescence. Two-dimensional flow-cytometric analysis revealed a fraction of cells distinct from the normal Fucci fluorescence pattern. Most of these cells were positive for an M phase marker, the phosphorylated form of histone H3. Cells growing in spheroids responded similarly to the drug, and the inner quiescent fraction also responded after recruitment to the growth fraction. When such drug-treated cells were irradiated in monolayer, a remarkable radiosensitization was observed. To determine whether this radiosensitization was truly due to the synchronization in M phase, we compared the radiosensitivity of cells synchronized by KPU-300 treatment and cells in early M phase isolated by a combined method that took advantage of shake-off and the properties of the Fucci system. Following normalization against the surviving fraction of cells treated with KPU-300 alone, the surviving fractions of cells irradiated in early M phase coincided. Taken together with potential vascular disrupting function in vivo, we propose a novel radiosensitizing strategy using KPU-300. PMID:26716455

KPU-300, a Novel Benzophenone-Diketopiperazine-Type Anti-Microtubule Agent with a 2-Pyridyl Structure, Is a Potent Radiosensitizer That Synchronizes the Cell Cycle in Early M Phase.

PubMed

Okuyama, Kohei; Kaida, Atsushi; Hayashi, Yoshiki; Hayashi, Yoshio; Harada, Kiyoshi; Miura, Masahiko

2015-01-01

KPU-300 is a novel colchicine-type anti-microtubule agent derived from plinabulin (NPI-2358). We characterized the effects of KPU-300 on cell cycle kinetics and radiosensitization using HeLa cells expressing the fluorescent ubiquitination-based cell cycle indicator (Fucci). Cells treated with 30 nM KPU-300 for 24 h were efficiently synchronized in M phase and contained clearly detectable abnormal Fucci fluorescence. Two-dimensional flow-cytometric analysis revealed a fraction of cells distinct from the normal Fucci fluorescence pattern. Most of these cells were positive for an M phase marker, the phosphorylated form of histone H3. Cells growing in spheroids responded similarly to the drug, and the inner quiescent fraction also responded after recruitment to the growth fraction. When such drug-treated cells were irradiated in monolayer, a remarkable radiosensitization was observed. To determine whether this radiosensitization was truly due to the synchronization in M phase, we compared the radiosensitivity of cells synchronized by KPU-300 treatment and cells in early M phase isolated by a combined method that took advantage of shake-off and the properties of the Fucci system. Following normalization against the surviving fraction of cells treated with KPU-300 alone, the surviving fractions of cells irradiated in early M phase coincided. Taken together with potential vascular disrupting function in vivo, we propose a novel radiosensitizing strategy using KPU-300.

Fractionated Ionizing Radiation Promotes Epithelial-Mesenchymal Transition in Human Esophageal Cancer Cells through PTEN Deficiency-Mediated Akt Activation.

PubMed

He, Enhui; Pan, Fei; Li, Guangchao; Li, Jingjing

2015-01-01

In some esophageal cancer patients, radiotherapy may not prevent distant metastasis thus resulting in poor survival. The underlying mechanism of metastasis in these patients is not well established. In this study, we have demonstrated that ionizing radiation may induce epithelial-mesenchymal transition (EMT) accompanied with increased cell migration and invasion, through downregulation of phosphatase and tensin homolog (PTEN), and activation of Akt/GSK-3β/Snail signaling. We developed a radioresistant (RR) esophageal squamous cancer cell line, KYSE-150/RR, by fractionated ionizing radiation (IR) treatment, and confirmed its radioresistance using a clonogenic survival assay. We found that the KYSE-150/RR cell line displayed typical morphological and molecular characteristics of EMT. In comparison to the parental cells, KYSE-150/RR cells showed an increase in post-IR colony survival, migration, and invasiveness. Furthermore, a decrease in PTEN in KYSE-150/RR cells was observed. We postulated that over-expression of PTEN may induce mesenchymal-epithelial transition in KYSE-150/RR cells and restore IR-induced increase of cell migration. Mechanistically, fractionated IR inhibits expression of PTEN, which leads to activation of Akt/GSK-3β signaling and is associated with the elevated levels of Snail protein, a transcription factor involved in EMT. Correspondingly, treatment with LY294002, a phosphatidylinositol-3-kinase inhibitor, mimicked PTEN overexpression effect in KYSE-150/RR cells, further suggesting a role for the Akt/GSK-3β/Snail signaling in effects mediated through PTEN. Together, these results strongly suggest that fractionated IR-mediated EMT in KYSE-150/RR cells is through PTEN-dependent pathways, highlighting a direct proinvasive effect of radiation treatment on tumor cells.

A microdosimetric study of {sup 10}B(n,{alpha}){sup 7}Li and {sup 157}Gd(n,{gamma}) reactions for neutron capture therapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, C.K.C.; Sutton, M.; Evans, T.M.

1999-01-01

This paper presents the microdosimetric analysis for the most interesting cell survival experiment recently performed at the Brookhaven National Laboratory (BNL). In this experiment, the cells were first treated with a gadolinium (Gd) labeled tumor-seeking boronated porphyrin (Gd-BOPP) or with BOPP alone, and then irradiated with thermal neutrons. The resulting cell-survival curves indicate that the {sup 157}Gd(n,{gamma}) reactions are very effective in cell killing. The death of a cell treated with Gd-BOPP was attributed to either the {sup 10}B(n,{alpha}){sup 7}Li reactions or the {sup 157}Gd(n,{gamma}) reactions (or both). However, the quantitative relationship between the two types of reaction and themore » cell-survival fraction was not clear. This paper presents the microdosimetric analysis for the BNL experiment based on the measured experimental parameters, and the results clearly suggest a quantitative relationship between the two types of reaction and the cell survival fraction. The results also suggest new research in gadolinium neutron capture therapy (GdNCT) which may lead to a more practical modality than the boron neutron capture therapy (BNCT) for treating cancers.« less

TU-H-BRC-07: Therapeutic Benefit in Spatially Fractionated Radiotherapy (GRID) Using Helical Tomotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Narayanasamy, G; Zhang, X; Paudel, N

Purpose: The aim of this project is to study the therapeutic ratio (TR) for helical Tomotherapy (HT) based spatially fractionated radiotherapy (GRID). Estimation of TR was based on the linear-quadratic cell survival model by comparing the normal cell survival in a HT GRID to that of a uniform dose delivery in an open-field for the same tumor survival. Methods: HT GRID plan was generated using a patient specific virtual GRID block pattern of non-divergent, cylinder shaped holes using MLCs. TR was defined as the ratio of normal tissue surviving fraction (SF) under HT GRID irradiation to an open field irradiationmore » with an equivalent dose that result in the same tumor cell SF. The ratio was estimated from DVH data on ten patient plans with deep seated, bulky tumor approved by the treating radiation oncologist. Dependence of the TR values on radio-sensitivity of the tumor cells and prescription dose were also analyzed. Results: The mean ± standard deviation (SD) of TR was 4.0±0.7 (range: 3.1 to 5.5) for the 10 patients with single fraction dose of 20 Gy and tumor cell SF of 0.5 at 2 Gy. In addition, mean±SD of TR = 1±0.1 and 18.0±5.1 were found for tumor with SF of 0.3 and 0.7, respectively. Reducing the prescription dose to 15 and 10 Gy lowered the TR to 2.0±0.2 and 1.2±0.04 for a tumor cell SF of 0.5 at 2 Gy. In this study, the SF of normal cells was assumed to be 0.5 at 2 Gy. Conclusion: HT GRID displayed a significant therapeutic advantage over uniform dose from an open field irradiation. TR increases with the radioresistance of the tumor cells and with prescription dose.« less

Cell kill by megavoltage protons with high LET.

PubMed

Kuperman, Vadim Y

2016-07-21

The aim of the current study is to develop a radiobiological model which describes the effect of linear energy transfer (LET) on cell survival and relative biological effectiveness (RBE) of megavoltage protons. By assuming the existence of critical sites within a cell, analytical expression for cell survival S as a function of LET is derived. The obtained results indicate that in cases where dose per fraction is small, [Formula: see text] is a linear-quadratic (LQ) function of dose while both alpha and beta radio-sensitivities are non-linearly dependent on LET. In particular, in the current model alpha increases with increasing LET while beta decreases. Conversely, in the case of large dose per fraction, the LQ dependence of [Formula: see text] on dose is invalid. The proposed radiobiological model predicts cell survival probability and RBE which, in general, deviate from the results obtained by using conventional LQ formalism. The differences between the LQ model and that described in the current study are reflected in the calculated RBE of protons.

SU-E-J-65: Evaluation of a Radiation-Induced Cell Proliferation Probability Formula Using Monte Carlo Simulation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Watanabe, Y; Dahlman, E

2014-06-01

Purpose: To evaluate the analytic formula of the cell death probability after single fraction dose. Methods: Cancer cells endlessly divide, but radiation causes the cancer cells to die. Not all cells die right away after irradiation. Instead, they continue dividing for next few cell cycles before they stop dividing and die. At the end of every cell cycle, the cell decides if it undertakes the mitotic process with a certain probability, Pdiv, which is altered by the radiation. Previously, by using a simple analytic model of radiobiology experiments, we obtained a formula of Pdeath (= 1 − Pdiv). A questionmore » is if the proposed probability can reproduce the well-known survival data of the LQ model. In this study, we evaluated the formula by doing a Monte Carlo simulation of the cell proliferation process. Starting with Ns seed cells, the cell proliferation process was simulated for N generations or until all cells die. We counted the number of living cells at the end. Assuming that the cell colony survived when more than Nc cells were still alive, the surviving fraction S was estimated. We compared the S vs. dose, or S-D curve, with the LQ model. Results: The results indicated that our formula does not reproduce the experimentally observed S-D curve without selecting appropriate α and α/β. With parameter optimization, there was a fair agreement between the MC result and the LQ curve of dose lower than 20Gy. However, the survival fraction of MC decreased much faster in comparison to the LQ data for doses higher than 20 Gy. Conclusion: This study showed that the previously derived probability of cell death per cell cycle is not sufficiently accurate to replicate common radiobiological experiments. The formula must be modified by considering its cell cycle dependence and some other unknown effects.« less

Comparative survival analysis of Deinococcus radiodurans and the haloarchaea Natrialba magadii and Haloferax volcanii exposed to vacuum ultraviolet irradiation.

PubMed

Abrevaya, Ximena C; Paulino-Lima, Ivan G; Galante, Douglas; Rodrigues, Fabio; Mauas, Pablo J D; Cortón, Eduardo; Lage, Claudia de Alencar Santos

2011-12-01

The haloarchaea Natrialba magadii and Haloferax volcanii, as well as the radiation-resistant bacterium Deinococcus radiodurans, were exposed to vacuum UV (VUV) radiation at the Brazilian Synchrotron Light Laboratory. Cell monolayers (containing 10(5) to 10(6) cells per sample) were prepared over polycarbonate filters and irradiated under high vacuum (10(-5) Pa) with polychromatic synchrotron radiation. N. magadii was remarkably resistant to high vacuum with a survival fraction of (3.77±0.76)×10(-2), which was larger than that of D. radiodurans (1.13±0.23)×10(-2). The survival fraction of the haloarchaea H. volcanii, of (3.60±1.80)×10(-4), was much smaller. Radiation resistance profiles were similar between the haloarchaea and D. radiodurans for fluences up to 150 J m(-2). For fluences larger than 150 J m(-2), there was a significant decrease in the survival of haloarchaea, and in particular H. volcanii did not survive. Survival for D. radiodurans was 1% after exposure to the higher VUV fluence (1350 J m(-2)), while N. magadii had a survival lower than 0.1%. Such survival fractions are discussed regarding the possibility of interplanetary transfer of viable microorganisms and the possible existence of microbial life in extraterrestrial salty environments such as the planet Mars and Jupiter's moon Europa. This is the first work to report survival of haloarchaea under simulated interplanetary conditions.

Cellular uptake of {sup 212}BiOCl by Ehrlich ascites cells: A dosimetric analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Roeske, J.C.; Whitlock, J.L.; Harper, P.V.

1999-01-01

Bi-212 is an alpha-emitting radionuclide being investigated as a therapeutic agent in the intraperitoneal treatment of micrometastatic ovarian carcinoma. In evaluating a new therapeutic modality, cell-survival studies are often used as a means of quantifying the biological effects of radiation. In this analysis, Ehrlich ascites cells were irradiated under conditions similar to therapy in various concentrations of Bi-212. Immediately following irradiation, a cell survival assay was performed in which cells were plated and colonies were counted after 10--14 days. Both a macrodosimetric and a microdosimetric approach were used in analyzing these data. These models used as input the fraction ofmore » activity within the cell and in solution, the distribution of cell sizes, and the variation of LET along individual alpha-particle tracks. The results indicate that the energy deposited within the nucleus varies significantly among individual cells. There is a small fraction of cell nuclei which receive no hits, while the remaining cells receive energy depositions which can differ significantly from the mean value. These dosimetric parameters are correlated with measured cell survival and will be a useful predictor of outcome for therapeutic doses.« less

High growth fraction at 9 grays of radiotherapy is associated with a good prognosis for patients with cervical squamous cell carcinoma.

PubMed

Oka, K; Suzuki, Y; Nakano, T

2000-10-01

MIB-1, a murine monoclonal antibody, recognizes the Ki-67 antigen of routinely processed paraffin sections after microwave treatment. Cycling cells are positive for MIB-1 in their nucleus, and quiescent cells are negative for MIB-1. The MIB-1 labeling index represents the growth fraction of the cell population. A total of 150 cervical biopsy specimens were taken from 75 consecutive patients with cervical squamous cell carcinomas before radiotherapy (RT) and at 9 grays (Gy) of RT and were investigated to analyze the correlation between the MIB-1 labeling index or the deltaMIB-1 labeling index and patient prognosis or local disease control. The deltaMIB-1 index was calculated as the MIB-1 index at 9 Gy minus the MIB-1 index before RT. The mean MIB-1 index was 38% (range, 11-67%) before RT and 54% (range, 15-85%) at 9 Gy. The MIB-1 index at 9 Gy was related to prognosis, including overall survival (P = 0.025), disease free survival (P = 0. 024), and metastasis free survival (P = 0.045). Patients who had a deltaMIB-1 index > 20% showed a trend toward a higher disease free survival rate compared with patients who had a deltaMIB-1 index < 20% (P = 0.093). Neither the MIB-1 index nor the deltaMIB-1 index was associated with local disease control. The high growth fraction at 9 Gy is regarded as a predictive factor for a good prognosis in patients with cervical squamous cell carcinoma patients who undergo RT alone.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Šefl, Martin, E-mail: martin.sefl@gmail.com; Kyriakou, Ioanna; Emfietzoglou, Dimitris, E-mail: demfietz@cc.uoi.gr

Purpose: To study theoretically the impact on cell survival of the radionuclide uptake rate inside tumor cells for a single administration of a radiopharmaceutical. Methods: The instantaneous-uptake model of O’Donoghue [“The impact of tumor cell proliferation in radioimmunotherapy,” Cancer 73, 974–980 (1994)] for a proliferating cell population irradiated by an exponentially decreasing dose-rate is here extended to allow for the monoexponential uptake of the radiopharmaceutical by the targeted cells. The time derivative of the survival curve is studied in detail deducing an expression for the minimum of the surviving fraction and the biologically effective dose (BED). Results: Surviving fractions aremore » calculated over a parameter range that is clinically relevant and broad enough to establish general trends. Specifically, results are presented for the therapy radionuclides Y-90, I-131, and P-32, assuming uptake half-times 1–24 h, extrapolated initial dose-rates 0.5–1 Gy h{sup −1}, and a biological clearance half-life of seven days. Representative radiobiological parameters for radiosensitive and rapidly proliferating tumor cells are used, with cell doubling time equal to 2 days and α-coefficient equal to 0.3 and 0.5 Gy{sup −1}. It is shown that neglecting the uptake phase of the radiopharmaceutical (i.e., assuming instantaneous-uptake) results in a sizeable over-estimation of cell-kill (i.e., under-estimation of cell survival) even for uptake half-times of only a few hours. The differences between the exponential-uptake model and the instantaneous-uptake model become larger for high peak dose-rates, slow uptakes, and (slightly) for long-lived radionuclides. Moreover, the sensitivity of the survival curve on the uptake model was found to be higher for the tumor cells with the larger α-coefficient. Conclusions: The exponential-uptake rate of the radiopharmaceutical inside targeted cells appears to have a considerable effect on the survival of a proliferating cell population and might need to be considered in radiobiological models of tumor cell-kill in radionuclide therapy.« less

Modulating cell-to-cell variability and sensitivity to death ligands by co-drugging

NASA Astrophysics Data System (ADS)

Flusberg, Deborah A.; Sorger, Peter K.

2013-06-01

TRAIL (tumor necrosis factor-related apoptosis-inducing ligand) holds promise as an anti-cancer therapeutic but efficiently induces apoptosis in only a subset of tumor cell lines. Moreover, even in clonal populations of responsive lines, only a fraction of cells dies in response to TRAIL and individual cells exhibit cell-to-cell variability in the timing of cell death. Fractional killing in these cell populations appears to arise not from genetic differences among cells but rather from differences in gene expression states, fluctuations in protein levels and the extent to which TRAIL-induced death or survival pathways become activated. In this study, we ask how cell-to-cell variability manifests in cell types with different sensitivities to TRAIL, as well as how it changes when cells are exposed to combinations of drugs. We show that individual cells that survive treatment with TRAIL can regenerate the sensitivity and death-time distribution of the parental population, demonstrating that fractional killing is a stable property of cell populations. We also show that cell-to-cell variability in the timing and probability of apoptosis in response to treatment can be tuned using combinations of drugs that together increase apoptotic sensitivity compared to treatment with one drug alone. In the case of TRAIL, modulation of cell-to-cell variability by co-drugging appears to involve a reduction in the threshold for mitochondrial outer membrane permeabilization.

The potential value of the neutral comet assay and the expression of genes associated with DNA damage in assessing the radiosensitivity of tumor cells.

PubMed

Jayakumar, Sundarraj; Bhilwade, Hari N; Pandey, Badri N; Sandur, Santosh K; Chaubey, Ramesh C

2012-10-09

The assessment of tumor radiosensitivity would be particularly useful in optimizing the radiation dose during radiotherapy. Therefore, the degree of correlation between radiation-induced DNA damage, as measured by the alkaline and the neutral comet assays, and the clonogenic survival of different human tumor cells was studied. Further, tumor radiosensitivity was compared with the expression of genes associated with the cellular response to radiation damage. Five different human tumor cell lines were chosen and the radiosensitivity of these cells was established by clonogenic assay. Alkaline and neutral comet assays were performed in γ-irradiated cells (2-8Gy; either acute or fractionated). Quantitative PCR was performed to evaluate the expression of DNA damage response genes in control and irradiated cells. The relative radiosensitivity of the cell lines assessed by the extent of DNA damage (neutral comet assay) immediately after irradiation (4Gy or 6Gy) was in agreement with radiosensitivity pattern obtained by the clonogenic assay. The survival fraction of irradiated cells showed a better correlation with the magnitude of DNA damage measured by the neutral comet assay (r=-0.9; P<0.05; 6Gy) than evaluated by alkaline comet assay (r=-0.73; P<0.05; 6Gy). Further, a significant correlation between the clonogenic survival and DNA damage was observed in cells exposed to fractionated doses of radiation. Of 15 genes investigated in the gene expression study, HSP70, KU80 and RAD51 all showed significant positive correlations (r=0.9; P<0.05) with tumor radiosensitivity. Our study clearly demonstrated that the neutral comet assay was better than alkaline comet assay for assessment of radiosensitivities of tumor cells after acute or fractionated doses of irradiation. © 2012 Elsevier B.V. All rights reserved.

On a fundamental problem in radiation biology

NASA Technical Reports Server (NTRS)

Dugan, V.; Trujillo, R.

1974-01-01

Experimental evidence indicates that the radiation dose required to reduce a surviving population to a certain fraction of its original population is lower for vertebrate cells than for viruses. On the other hand, the number of ionizations per cell required to inactivate that cell is greater for vertebrate cells than for viruses. The apparent conflict between these two findings is investigated. It is found that the apparent contradiction is probably a result of the fractional power dependence of the radiation-dose value on the nucleic acid weight.

The radiosensitivity of a murine fibrosarcoma as measured by three cell survival assays.

PubMed Central

Rice, L.; Urano, M.; Suit, H. D.

1980-01-01

The radiation sensitivity of a weakly immunogenic spontaneous fibrosarcoma of the C3Hf/Sed mouse (designated FSa-II) was assessed by three in vivo cell survival methods: end-point dilution (TD50) assay, lung colony (LC) assay, and agar diffusion chamber (ADC) assay. The hypoxic fraction of this tumour was also determined by the ADC method. Although there was a good agreement of the cell survival data between the ADC and LC methods, the TD50 method yielded a considerably less steep cell survival curve. Beneficial aspects and limitations of each assay are discussed. In addition, the use of the ADC method for the growth of xenogeneic cell lines and a preliminary experiment with human tumour cells in non-immunosuppressed hosts suggest that this method may be a valuable adjunct for studying the growth and therapeutic responses of human tumour cells. PMID:6932931

A Rapid Survival Assay to Measure Drug-Induced Cytotoxicity and Cell Cycle Effects

PubMed Central

Valiathan, Chandni; McFaline, Jose L.

2012-01-01

We describe a rapid method to accurately measure the cytotoxicity of mammalian cells upon exposure to various drugs. Using this assay, we obtain survival data in a fraction of the time required to perform the traditional clonogenic survival assay, considered the gold standard. The dynamic range of the assay allows sensitivity measurements on a multi-log scale allowing better resolution of comparative sensitivities. Moreover, the results obtained contain additional information on cell cycle effects of the drug treatment. Cell survival is obtained from a quantitative comparison of proliferation between drug-treated and untreated cells. During the assay, cells are treated with a drug and, following a recovery period, allowed to proliferate in the presence of BrdU. Cells that synthesize DNA in the presence of bromodeoxyuridine (BrdU) exhibit quenched Hoechst fluorescence easily detected by flow cytometry; quenching is used to determine relative proliferation in treated versus untreated cells. Finally, the multi-well setup of this assay allows the simultaneous screening of multiple cell lines, multiple doses, or multiple drugs to accurately measure cell survival and cell cycle changes after drug treatment. PMID:22133811

Prognostic Implications of Multiplex Detection of KRAS Mutations in Cell-Free DNA from Patients with Pancreatic Ductal Adenocarcinoma.

PubMed

Kim, Min Kyeong; Woo, Sang Myung; Park, Boram; Yoon, Kyong-Ah; Kim, Yun-Hee; Joo, Jungnam; Lee, Woo Jin; Han, Sung-Sik; Park, Sang-Jae; Kong, Sun-Young

2018-04-01

Cell-free DNA (cfDNA) is known to provide potential biomarkers for predicting clinical outcome, but its value in pancreatic ductal adenocarcinoma (PDAC) has not been fully evaluated. The aim of this study was to evaluate the clinical applicability of quantitative analysis of multiplex KRAS mutations in cell-free DNA from patients with PDAC. A total of 106 patients with PDAC were enrolled in this prospective study. The concentration and fraction of KRAS mutations were determined through multiplex detection of KRAS mutations in plasma samples by use of a droplet digital PCR kit (Bio-Rad). KRAS mutations were detected in 96.1% of tissue samples. Eighty patients (80.5%) harbored KRAS mutations in cfDNA, with a median KRAS mutation concentration of 0.165 copies/μL and a median fractional abundance of 0.415%. Multivariable analyses demonstrated that the KRAS mutation concentration [hazard ratio (HR), 2.08; 95% CI, 1.20-3.63] and KRAS fraction (HR, 1.73; 95% CI, 1.02-2.95) were significant factors for progression-free survival. KRAS mutation concentration (HR, 1.97; 95% CI, 1.05-3.67) also had prognostic implications for overall survival. Subgroup analyses showed that KRAS mutation concentration and fractional abundance significantly affected progression-free survival in resectable PDAC ( P = 0.016). Moreover, when combined with the cancer biomarker CA19-9, the KRAS mutation concentration in cfDNA showed additive benefits for the prediction of overall survival. This study demonstrates that multiplex detection of KRAS mutations in plasma cfDNA is clinically relevant, providing a potential candidate biomarker for prognosis of PDAC. © 2018 American Association for Clinical Chemistry.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sugano, Yasutaka; Mizuta, Masahiro; Takao, Seishin

Purpose: Radiotherapy of solid tumors has been performed with various fractionation regimens such as multi- and hypofractionations. However, the ability to optimize the fractionation regimen considering the physical dose distribution remains insufficient. This study aims to optimize the fractionation regimen, in which the authors propose a graphical method for selecting the optimal number of fractions (n) and dose per fraction (d) based on dose–volume histograms for tumor and normal tissues of organs around the tumor. Methods: Modified linear-quadratic models were employed to estimate the radiation effects on the tumor and an organ at risk (OAR), where the repopulation of themore » tumor cells and the linearity of the dose-response curve in the high dose range of the surviving fraction were considered. The minimization problem for the damage effect on the OAR was solved under the constraint that the radiation effect on the tumor is fixed by a graphical method. Here, the damage effect on the OAR was estimated based on the dose–volume histogram. Results: It was found that the optimization of fractionation scheme incorporating the dose–volume histogram is possible by employing appropriate cell surviving models. The graphical method considering the repopulation of tumor cells and a rectilinear response in the high dose range enables them to derive the optimal number of fractions and dose per fraction. For example, in the treatment of prostate cancer, the optimal fractionation was suggested to lie in the range of 8–32 fractions with a daily dose of 2.2–6.3 Gy. Conclusions: It is possible to optimize the number of fractions and dose per fraction based on the physical dose distribution (i.e., dose–volume histogram) by the graphical method considering the effects on tumor and OARs around the tumor. This method may stipulate a new guideline to optimize the fractionation regimen for physics-guided fractionation.« less

Enhancement of radiation therapy by the novel vascular targeting agent ZD6126.

PubMed

Siemann, Dietmar W; Rojiani, Amyn M

2002-05-01

The aim of this study was to evaluate the antitumor efficacy of the novel vascular targeting agent ZD6126 (N-acetylcochinol-O-phosphate) in the rodent KHT sarcoma model, either alone or in combination with single- or fractionated-dose radiation therapy. C3H/HeJ mice bearing i.m. KHT tumors were injected i.p. with ZD6126 doses ranging from 10 to 150 mg/kg. Tumors were irradiated locally in unanesthetized mice using a linear accelerator. Tumor response to ZD6126 administered alone or in combination with radiation was assessed by clonogenic cell survival assay or tumor growth delay. Treatment with ZD6126 led to a rapid tumor vascular shutdown as determined by Hoechst 33342 diffusion. Histologic evaluation showed morphologic damage of tumor cells within a few hours after drug exposure, followed by extensive central tumor necrosis and neoplastic cell death as a result of prolonged ischemia. When combined with radiation, a 150 mg/kg dose of ZD6126 reduced tumor cell survival 10-500-fold compared with radiation alone. These enhancements in tumor cell killing could be achieved for ZD6126 given both before and after radiation exposure. Further, the shape of the cell survival curve observed after the combination therapy suggested that including ZD6126 in the treatment had a major effect on the radiation-resistant hypoxic cell subpopulation associated with this tumor. Finally, when given on a once-weekly basis in conjunction with fractionated radiotherapy, ZD6126 treatment was found to significantly increase the tumor response to daily 2.5 Gy fractions. The present results demonstrated that in the KHT sarcoma, ZD6126 caused rapid tumor vascular shutdown, induction of central tumor necrosis, tumor cell death secondary to ischemia, and enhancement of the antitumor effects of radiation therapy.

Pooled analysis of stereotactic ablative radiotherapy for primary renal cell carcinoma: A report from the International Radiosurgery Oncology Consortium for Kidney (IROCK).

PubMed

Siva, Shankar; Louie, Alexander V; Warner, Andrew; Muacevic, Alexander; Gandhidasan, Senthilkumar; Ponsky, Lee; Ellis, Rodney; Kaplan, Irving; Mahadevan, Anand; Chu, William; Swaminath, Anand; Onishi, Hiroshi; Teh, Bin; Correa, Rohann J; Lo, Simon S; Staehler, Michael

2018-03-01

Stereotactic ablative radiotherapy (SABR) is an emerging therapy for primary renal cell carcinoma. The authors assessed safety, efficacy, and survival in a multi-institutional setting. Outcomes between single-fraction and multifraction SABR were compared. Individual patient data sets from 9 International Radiosurgery Oncology Consortium for Kidney institutions across Germany, Australia, the United States, Canada, and Japan were pooled. Toxicities were recorded using Common Terminology Criteria for Adverse Events, version 4.0. Patient, tumor, and treatment characteristics were stratified according to the number of radiotherapy fractions (single vs multiple). Survival outcomes were examined using Kaplan-Meier estimates and Cox proportional-hazards regression. Of 223 patients, 118 received single-fraction SABR, and 105 received multifraction SABR. The mean patient age was 72 years, and 69.5% of patients were men. There were 83 patients with grade 1 and 2 toxicity (35.6%) and 3 with grade 3 and 4 toxicities (1.3%). The rates of local control, cancer-specific survival, and progression-free survival were 97.8%, 95.7%, and 77.4%, respectively, at 2 years; and they were 97.8%, 91.9%, and 65.4%, respectively, at 4 years. On multivariable analysis, tumors with a larger maximum dimension and the receipt of multifraction SABR were associated with poorer progression-free survival (hazard ratio, 1.16 [P < .01] and 1.13 [P = .02], respectively) and poorer cancer-specific survival (hazard ratio, 1.28 [P < .01] and 1.33 [P = .01], respectively). There were no differences in local failure between the single-fraction cohort (n = 1) and the multifraction cohort (n = 2; P = .60). The mean ( ± standard deviation) estimated glomerular filtration rate at baseline was 59.9 ± 21.9 mL per minute, and it decreased by 5.5 ± 13.3 mL per minute (P < .01). SABR is well tolerated and locally effective for treating patients who have primary renal cell carcinoma and has an acceptable impact on renal function. An interesting observation is that patients who receive single-fraction SABR appear to be less likely to progress distantly or to die of cancer. Cancer 2018;124:934-42. © 2017 American Cancer Society. © 2017 American Cancer Society.

Role of radiotherapy fractionation in head and neck cancers (MARCH): an updated meta-analysis

PubMed Central

Lacas, Benjamin; Bourhis, Jean; Overgaard, Jens; Zhang, Qiang; Gregoire, Vincent; Nankivell, Matthew; Zackrisson, Bjorn; Szutkowski, Zbigniew; Suwiński, Rafał; Poulsen, Michael; O’Sullivan, Brian; Corvo, Renzo; Laskar, Sarbani Ghosh; Fallai, Carlo; Yamazaki, Hideya; Dobrowsky, Werner; Cho, Kwan Ho; Garden, Adam S; Langendijk, Johannes A; Viegas, Celia Maria Pais; Hay, John; Lotayef, Mohamed; Parmar, Mahesh K B; Auperin, Anne; van Herpen, Carla; Maingon, Philippe; Trotti, Andy M; Grau, Cai; Pignon, Jean-Pierre; Blanchard, Pierre

2017-01-01

Summary Background The Meta-Analysis of Radiotherapy in squamous cell Carcinomas of Head and neck (MARCH) showed that altered fractionation radiotherapy is associated with improved overall and progression-free survival compared with conventional radiotherapy, with hyperfractionated radiotherapy showing the greatest benefit. This update aims to confirm and explain the superiority of hyperfractionated radiotherapy over other altered fractionation radiotherapy regimens and to assess the benefit of altered fractionation within the context of concomitant chemotherapy with the inclusion of new trials. Methods For this updated meta-analysis, we searched bibliography databases, trials registries, and meeting proceedings for published or unpublished randomised trials done between Jan 1, 2009, and July 15, 2015, comparing primary or postoperative conventional fractionation radiotherapy versus altered fractionation radiotherapy (comparison 1) or conventional fractionation radiotherapy plus concomitant chemotherapy versus altered fractionation radiotherapy alone (comparison 2). Eligible trials had to start randomisation on or after Jan 1, 1970, and completed accrual before Dec 31, 2010; had to have been randomised in a way that precluded prior knowledge of treatment assignment; and had to include patients with non-metastatic squamous cell carcinoma of the oral cavity, oropharynx, hypopharynx, or larynx undergoing first-line curative treatment. Trials including a non-conventional radiotherapy control group, investigating hypofractionated radiotherapy, or including mostly nasopharyngeal carcinomas were excluded. Trials were grouped in three types of altered fractionation: hyperfractionated, moderately accelerated, and very accelerated. Individual patient data were collected and combined with a fixed-effects model based on the intention-to-treat principle. The primary endpoint was overall survival. Findings Comparison 1 (conventional fractionation radiotherapy vs altered fractionation radiotherapy) included 33 trials and 11 423 patients. Altered fractionation radiotherapy was associated with a significant benefit on overall survival (hazard ratio [HR] 0·94, 95% CI 0·90–0·98; p=0·0033), with an absolute difference at 5 years of 3·1% (95% CI 1·3–4·9) and at 10 years of 1·2% (−0·8 to 3·2). We found a significant interaction (p=0·051) between type of fractionation and treatment effect, the overall survival benefit being restricted to the hyperfractionated group (HR 0·83, 0·74–0·92), with absolute differences at 5 years of 8·1% (3·4 to 12·8) and at 10 years of 3·9% (−0·6 to 8·4). Comparison 2 (conventional fractionation radiotherapy plus concomitant chemotherapy versus altered fractionation radiotherapy alone) included five trials and 986 patients. Overall survival was significantly worse with altered fractionation radiotherapy compared with concomitant chemoradiotherapy (HR 1·22, 1·05–1·42; p=0·0098), with absolute differences at 5 years of −5·8% (−11·9 to 0·3) and at 10 years of −5·1% (−13·0 to 2·8). Interpretation This update confirms, with more patients and a longer follow-up than the first version of MARCH, that hyperfractionated radiotherapy is, along with concomitant chemoradiotherapy, a standard of care for the treatment of locally advanced head and neck squamous cell cancers. The comparison between hyperfractionated radiotherapy and concomitant chemoradiotherapy remains to be specifically tested. PMID:28757375

Apoptosis-inducing activity of HPLC fraction from Voacanga globosa (Blanco) Merr. on the human colon carcinoma cell.

PubMed

Acebedo, Alvin Resultay; Amor, Evangeline Cancio; Jacinto, Sonia Donaldo

2014-01-01

Voacanga globosa (Blanco), a plant endemic to the Philippines, is traditionally used especially by indigenous people of Bataan in the treatment of ulcers, wounds and tumorous growths. This study aimed to provide scientific evidence to therapeutic properties by determining cytotoxic and pro-apoptotic activity of HPLC fractions from leaves on HCT116 human colon carcinoma and A549 human lung carcinoma cell lines. Ethanolic extraction was performed on V globosa leaves followed by hexane and ethyl acetate partitioning. Silica gel column chromatography and high performance liquid chromatography (HPLC) produced MP1, MP2 and MP3 fractions. Cytotoxic activity of the fractions was determined through MTT assay against the cancer cell lines HCT116 and A549 and the non-cancer AA8 Chinese hamster ovarian cell line. Pro-apoptotic activities of the most active fractions were further assessed through DAPI staining, TUNEL assay and JC-1 mitochondrial membrane potential assay with HCT116 cells. While the MP1 fraction exerted no significant activity against all cell lines tested, MP2 and MP3 fractions demonstrated high toxicity against HCT116 and A549 cells. The MP3 fraction induced formation of apoptotic bodies, condensed DNA and other morphological changes consistent with apoptosis of HCT116 cells and TUNEL assay showed significant increase in DNA fragmentation over time. In these cells, the MP3 fraction also induced mitochondrial membrane destabilization, which is generally associated with the beginning of apoptosis. Phytochemical analysis demonstrated the presence only of saponins and terpenoids in the MP3 fraction. The results indicate that the MP3 fraction exerts cytotoxic activity on HCT116 cells via induction of apoptosis triggered by loss of mitochondrial membrane potential crucial for cell survival.

Incorporating Cancer Stem Cells in Radiation Therapy Treatment Response Modeling and the Implication in Glioblastoma Multiforme Treatment Resistance

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yu, Victoria Y.; Nguyen, Dan; Pajonk, Frank

Purpose: To perform a preliminary exploration with a simplistic mathematical cancer stem cell (CSC) interaction model to determine whether the tumor-intrinsic heterogeneity and dynamic equilibrium between CSCs and differentiated cancer cells (DCCs) can better explain radiation therapy treatment response with a dual-compartment linear-quadratic (DLQ) model. Methods and Materials: The radiosensitivity parameters of CSCs and DCCs for cancer cell lines including glioblastoma multiforme (GBM), non–small cell lung cancer, melanoma, osteosarcoma, and prostate, cervical, and breast cancer were determined by performing robust least-square fitting using the DLQ model on published clonogenic survival data. Fitting performance was compared with the single-compartment LQ (SLQ) and universalmore » survival curve models. The fitting results were then used in an ordinary differential equation describing the kinetics of DCCs and CSCs in response to 2- to 14.3-Gy fractionated treatments. The total dose to achieve tumor control and the fraction size that achieved the least normal biological equivalent dose were calculated. Results: Smaller cell survival fitting errors were observed using DLQ, with the exception of melanoma, which had a low α/β = 0.16 in SLQ. Ordinary differential equation simulation indicated lower normal tissue biological equivalent dose to achieve the same tumor control with a hypofractionated approach for 4 cell lines for the DLQ model, in contrast to SLQ, which favored 2 Gy per fraction for all cells except melanoma. The DLQ model indicated greater tumor radioresistance than SLQ, but the radioresistance was overcome by hypofractionation, other than the GBM cells, which responded poorly to all fractionations. Conclusion: The distinct radiosensitivity and dynamics between CSCs and DCCs in radiation therapy response could perhaps be one possible explanation for the heterogeneous intertumor response to hypofractionation and in some cases superior outcome from stereotactic ablative radiation therapy. The DLQ model also predicted the remarkable GBM radioresistance, a result that is highly consistent with clinical observations. The radioresistance putatively stemmed from accelerated DCC regrowth that rapidly restored compartmental equilibrium between CSCs and DCCs.« less

Survival of microbial life under shock compression: implications for Panspermia

NASA Astrophysics Data System (ADS)

Burchell, M.

2007-09-01

An analysis is carried out of the survival fraction of micro-organisms exposed to extreme shock pressures. A variety of data sources are used in this analysis. The key findings are that survival depends on the behaviour of the cell wall. Below a critical shock pressure there is a relatively slow fall in survival fraction as shock pressures increase. Above the critical threshold survival starts to fall rapidly as shock pressure increases further. The critical shock pressures found here are in the range 2.4 to 20 GPa, and vary not only from organism to organism, but also depend on the growth stage of given organisms, with starved (i.e., no growth) states favoured for survival. At the shock pressures typical of those involved in interplanetary transfer of rocky materials, the survival fractions are found to be small but finite. This lends credence to the idea of Panspermia, i.e. life may naturally migrate through space. Thus for example, Martian meteorites should not a prior be considered as sterile due to the shock processes they have undergone, but their lack of viable micro-organisms either reflects no such life being present at the source at the time of departure or the influence of other hazardous processes such as radiation in space or heating of surfaces during entry into a planetary atmosphere.

Flow cytometric DNA analysis of cirrhotic liver cells in patients with hepatocellular carcinoma can provide a new prognostic factor.

PubMed

Ruà, S; Comino, A; Fruttero, A; Torchio, P; Bouzari, H; Taraglio, S; Torchio, B; Capussotti, L

1996-09-15

DNA flow cytometry of hepatocellular carcinoma (HCC) cells has been investigated in many studies, but, to the best of our knowledge, there are no data on DNA analysis of cirrhotic parenchyma around the HCC. In this study, cell kinetics and ploidy of parenchymal cells around HCC were performed to ascertain if this would predict the possibility of recurrence in the cirrhotic areas. The DNA content of 93 cases of HCC and of cirrhotic liver around the tumor nodules was analyzed by flow cytometry. Ploidy and proliferative index of HCC and cirrhotic liver were compared with macroscopic, histologic, and clinical features of each case and linked with the behavior of these tumors. Survival curves were assessed according to the Kaplan-Meier method. A multivariate analysis based on Cox proportional hazards regression model was performed on cases of diploid cirrhosis cells in which the S-phase fraction was evaluable. The univariate analysis of survival suggested significant roles for age, number of intrahepatic nodules, Edmondson-Steiner's classification, portal invasion, vascular invasion, presence of necrosis, hepatitis B surface antigen, alpha-feto-protein, Child's score, ploidy, and S-phase fraction of HCC cells. The DNA analysis of the cirrhotic cells showed that polyploidy was dramatically reduced in patients with HCC, compared with normal hepatocytes, and aneuploid clones were present among diploid cells. High S-phase fraction of cirrhotic cells and Child-Pugh classification were the strongest independent parameters affecting the tumor behavior in this study. The results of this study suggest that S-phase fraction of cirrhotic liver parenchyma may be employed as a new parameter in the prognostic evaluation of HCC patients.

Association of Cell-Free DNA Tumor Fraction and Somatic Copy Number Alterations With Survival in Metastatic Triple-Negative Breast Cancer

PubMed Central

Stover, Daniel G.; Parsons, Heather A.; Ha, Gavin; Freeman, Samuel S.; Barry, William T.; Guo, Hao; Choudhury, Atish D.; Gydush, Gregory; Reed, Sarah C.; Rhoades, Justin; Rotem, Denisse; Hughes, Melissa E.; Dillon, Deborah A.; Partridge, Ann H.; Wagle, Nikhil; Krop, Ian E.; Getz, Gad; Golub, Todd R.; Love, J. Christopher; Winer, Eric P.; Tolaney, Sara M.; Lin, Nancy U.

2018-01-01

Purpose Cell-free DNA (cfDNA) offers the potential for minimally invasive genome-wide profiling of tumor alterations without tumor biopsy and may be associated with patient prognosis. Triple-negative breast cancer (TNBC) is characterized by few mutations but extensive somatic copy number alterations (SCNAs), yet little is known regarding SCNAs in metastatic TNBC. We sought to evaluate SCNAs in metastatic TNBC exclusively via cfDNA and determine if cfDNA tumor fraction is associated with overall survival in metastatic TNBC. Patients and Methods In this retrospective cohort study, we identified 164 patients with biopsy-proven metastatic TNBC at a single tertiary care institution who received prior chemotherapy in the (neo)adjuvant or metastatic setting. We performed low-coverage genome-wide sequencing of cfDNA from plasma. Results Without prior knowledge of tumor mutations, we determined tumor fraction of cfDNA for 96.3% of patients and SCNAs for 63.9% of patients. Copy number profiles and percent genome altered were remarkably similar between metastatic and primary TNBCs. Certain SCNAs were more frequent in metastatic TNBCs relative to paired primary tumors and primary TNBCs in publicly available data sets The Cancer Genome Atlas and METABRIC, including chromosomal gains in drivers NOTCH2, AKT2, and AKT3. Prespecified cfDNA tumor fraction threshold of ≥ 10% was associated with significantly worse metastatic survival (median, 6.4 v 15.9 months) and remained significant independent of clinicopathologic factors (hazard ratio, 2.14; 95% CI, 1.4 to 3.8; P < .001). Conclusion We present the largest genomic characterization of metastatic TNBC to our knowledge, exclusively from cfDNA. Evaluation of cfDNA tumor fraction was feasible for nearly all patients, and tumor fraction ≥ 10% is associated with significantly worse survival in this large metastatic TNBC cohort. Specific SCNAs are enriched and prognostic in metastatic TNBC, with implications for metastasis, resistance, and novel therapeutic approaches. PMID:29298117

Association of Cell-Free DNA Tumor Fraction and Somatic Copy Number Alterations With Survival in Metastatic Triple-Negative Breast Cancer.

PubMed

Stover, Daniel G; Parsons, Heather A; Ha, Gavin; Freeman, Samuel S; Barry, William T; Guo, Hao; Choudhury, Atish D; Gydush, Gregory; Reed, Sarah C; Rhoades, Justin; Rotem, Denisse; Hughes, Melissa E; Dillon, Deborah A; Partridge, Ann H; Wagle, Nikhil; Krop, Ian E; Getz, Gad; Golub, Todd R; Love, J Christopher; Winer, Eric P; Tolaney, Sara M; Lin, Nancy U; Adalsteinsson, Viktor A

2018-02-20

Purpose Cell-free DNA (cfDNA) offers the potential for minimally invasive genome-wide profiling of tumor alterations without tumor biopsy and may be associated with patient prognosis. Triple-negative breast cancer (TNBC) is characterized by few mutations but extensive somatic copy number alterations (SCNAs), yet little is known regarding SCNAs in metastatic TNBC. We sought to evaluate SCNAs in metastatic TNBC exclusively via cfDNA and determine if cfDNA tumor fraction is associated with overall survival in metastatic TNBC. Patients and Methods In this retrospective cohort study, we identified 164 patients with biopsy-proven metastatic TNBC at a single tertiary care institution who received prior chemotherapy in the (neo)adjuvant or metastatic setting. We performed low-coverage genome-wide sequencing of cfDNA from plasma. Results Without prior knowledge of tumor mutations, we determined tumor fraction of cfDNA for 96.3% of patients and SCNAs for 63.9% of patients. Copy number profiles and percent genome altered were remarkably similar between metastatic and primary TNBCs. Certain SCNAs were more frequent in metastatic TNBCs relative to paired primary tumors and primary TNBCs in publicly available data sets The Cancer Genome Atlas and METABRIC, including chromosomal gains in drivers NOTCH2, AKT2, and AKT3. Prespecified cfDNA tumor fraction threshold of ≥ 10% was associated with significantly worse metastatic survival (median, 6.4 v 15.9 months) and remained significant independent of clinicopathologic factors (hazard ratio, 2.14; 95% CI, 1.4 to 3.8; P < .001). Conclusion We present the largest genomic characterization of metastatic TNBC to our knowledge, exclusively from cfDNA. Evaluation of cfDNA tumor fraction was feasible for nearly all patients, and tumor fraction ≥ 10% is associated with significantly worse survival in this large metastatic TNBC cohort. Specific SCNAs are enriched and prognostic in metastatic TNBC, with implications for metastasis, resistance, and novel therapeutic approaches.

Radiosensitivity of Prostate Cancer Cell Lines for Irradiation from Beta Particle-emitting Radionuclide ¹⁷⁷Lu Compared to Alpha Particles and Gamma Rays.

PubMed

Elgqvist, Jörgen; Timmermand, Oskar Vilhelmsson; Larsson, Erik; Strand, Sven-Erik

2016-01-01

The purpose of the present study was to investigate the radiosensitivity of the prostate cancer cell lines LNCaP, DU145, and PC3 when irradiated with beta particles emitted from (177)Lu, and to compare the effect with irradiation using alpha particles or gamma rays. Cells were irradiated with beta particles emitted from (177)Lu, alpha particles from (241)Am, or gamma rays from (137)Cs. A non-specific polyclonal antibody was labeled with (177)Lu and used to irradiate cells in suspension with beta particles. A previously described in-house developed alpha-particle irradiator based on a (241)Am source was used to irradiate cells with alpha particles. External gamma-ray irradiation was achieved using a standard (137)Cs irradiator. Cells were irradiated to absorbed doses equal to 0, 0.5, 1, 2, 4, 6, 8, or 10 Gy. The absorbed doses were calculated as mean absorbed doses. For evaluation of cell survival, the tetrazolium-based WST-1 assay was used. After irradiation, WST-1 was added to the cell solutions, incubated, and then measured for level of absorbance at 450 nm, indicating the live and viable cells. LNCaP, DU145, and PC3 cell lines all had similar patterns of survival for the different radiation types. No significant difference in surviving fractions were observed between cells treated with beta-particle and gamma-ray irradiation, represented for example by the surviving fraction values (mean±SD) at 2, 6, and 10 Gy (SF2, SF6, and SF10) for DU145 after beta-particle irradiation: 0.700±0.090, 0.186±0.050 and 0.056±0.010, respectively. A strong radiosensitivity to alpha particles was observed, with SF2 values of 0.048±0.008, 0.018±0.006 and 0.015±0.005 for LNCaP, DU145, and PC3, respectively. The surviving fractions after irradiation using beta particles or gamma rays did not differ significantly at the absorbed dose levels and dose rates used. Irradiation using alpha particles led to a high level of cell killing. The results show that the beta-particle emitter (177)Lu as well as alpha-particles are both good candidates for radionuclide-therapy applications in the treatment of prostate cancer. Copyright© 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

Apoptosis, energy metabolism, and fraction of radiobiologically hypoxic cells: a study of human melanoma multicellular spheroids.

PubMed

Rofstad, E K; Eide, K; Skøyum, R; Hystad, M E; Lyng, H

1996-09-01

The magnitude of the fraction of radiobiologically hypoxic cells in tumours is generally believed to reflect the efficiency of the vascular network. Theoretical studies have suggested that the hypoxic fraction might also be influenced by biological properties of the tumour cells. Quantitative experimental results of cell energy metabolism, hypoxia- induced apoptosis, and radiobiological hypoxia are reported here. Human melanoma multicellular spheroids (BEX-c and WIX-c) were used as tumour models to avoid confounding effects of the vascular network. Radiobiological studies showed that the fractions of hypoxic cells in 1000-microM spheroids were 32 +/- 12% (BEX-c) and 2.5 +/- 1.1% (WIX-c). The spheroid hypoxic volume fractions (28 +/- 6% (BEX-c) and 1.4 +/- 7% (WIX-c)), calculated from the rate of oxygen consumption per cell, the cell packing density, and the thickness of the viable rim, were similar to the fractions of radiobiologically hypoxic cells. Large differences between tumours in fraction of hypoxic cells are therefore not necessarily a result of differences in the efficiency of the vascular network. Studies of monolayer cell cultures, performed to identify the biological properties of the BEX-c and WIX-c cells leading to this large difference in fraction of hypoxic cells, gave the following results: (1) WIX-c showed lower cell surviving fractions after exposure to hypoxia than BEX-c, (2) WIX-c showed higher glucose uptake and lactate release rates than BEX-c both under aerobic and hypoxic conditions, and (3) hypoxia induced apoptosis in WIX-c but not in BEX-c. These observations suggested that the difference between BEX-c and WIX-c spheroids in fraction of hypoxic cells resulted partly from differences in cell energy metabolism and partly from a difference in capacity to retain viability under hypoxic stress. The induction of apoptosis by hypoxia was identified as a phenomenon which has an important influence on the magnitude of the fraction of radiobiologically hypoxic cells in multicellular spheroids.

Ill-posed problem and regularization in reconstruction of radiobiological parameters from serial tumor imaging data

NASA Astrophysics Data System (ADS)

Chvetsov, Alevei V.; Sandison, George A.; Schwartz, Jeffrey L.; Rengan, Ramesh

2015-11-01

The main objective of this article is to improve the stability of reconstruction algorithms for estimation of radiobiological parameters using serial tumor imaging data acquired during radiation therapy. Serial images of tumor response to radiation therapy represent a complex summation of several exponential processes as treatment induced cell inactivation, tumor growth rates, and the rate of cell loss. Accurate assessment of treatment response would require separation of these processes because they define radiobiological determinants of treatment response and, correspondingly, tumor control probability. However, the estimation of radiobiological parameters using imaging data can be considered an inverse ill-posed problem because a sum of several exponentials would produce the Fredholm integral equation of the first kind which is ill posed. Therefore, the stability of reconstruction of radiobiological parameters presents a problem even for the simplest models of tumor response. To study stability of the parameter reconstruction problem, we used a set of serial CT imaging data for head and neck cancer and a simplest case of a two-level cell population model of tumor response. Inverse reconstruction was performed using a simulated annealing algorithm to minimize a least squared objective function. Results show that the reconstructed values of cell surviving fractions and cell doubling time exhibit significant nonphysical fluctuations if no stabilization algorithms are applied. However, after applying a stabilization algorithm based on variational regularization, the reconstruction produces statistical distributions for survival fractions and doubling time that are comparable to published in vitro data. This algorithm is an advance over our previous work where only cell surviving fractions were reconstructed. We conclude that variational regularization allows for an increase in the number of free parameters in our model which enables development of more-advanced parameter reconstruction algorithms.

Hypofractionation Results in Reduced Tumor Cell Kill Compared to Conventional Fractionation for Tumors With Regions of Hypoxia

DOE Office of Scientific and Technical Information (OSTI.GOV)

Carlson, David J., E-mail: david.j.carlson@yale.ed; Yale University School of Medicine, Department of Therapeutic Radiology, New Haven, CT; Keall, Paul J.

2011-03-15

Purpose: Tumor hypoxia has been observed in many human cancers and is associated with treatment failure in radiation therapy. The purpose of this study is to quantify the effect of different radiation fractionation schemes on tumor cell killing, assuming a realistic distribution of tumor oxygenation. Methods and Materials: A probability density function for the partial pressure of oxygen in a tumor cell population is quantified as a function of radial distance from the capillary wall. Corresponding hypoxia reduction factors for cell killing are determined. The surviving fraction of a tumor consisting of maximally resistant cells, cells at intermediate levels ofmore » hypoxia, and normoxic cells is calculated as a function of dose per fraction for an equivalent tumor biological effective dose under normoxic conditions. Results: Increasing hypoxia as a function of distance from blood vessels results in a decrease in tumor cell killing for a typical radiotherapy fractionation scheme by a factor of 10{sup 5} over a distance of 130 {mu}m. For head-and-neck cancer and prostate cancer, the fraction of tumor clonogens killed over a full treatment course decreases by up to a factor of {approx}10{sup 3} as the dose per fraction is increased from 2 to 24 Gy and from 2 to 18 Gy, respectively. Conclusions: Hypofractionation of a radiotherapy regimen can result in a significant decrease in tumor cell killing compared to standard fractionation as a result of tumor hypoxia. There is a potential for large errors when calculating alternate fractionations using formalisms that do not account for tumor hypoxia.« less

Redefining relative biological effectiveness in the context of the EQDX formalism: implications for alpha-particle emitter therapy.

PubMed

Hobbs, Robert F; Howell, Roger W; Song, Hong; Baechler, Sébastien; Sgouros, George

2014-01-01

Alpha-particle radiopharmaceutical therapy (αRPT) is currently enjoying increasing attention as a viable alternative to chemotherapy for targeting of disseminated micrometastatic disease. In theory, αRPT can be personalized through pre-therapeutic imaging and dosimetry. However, in practice, given the particularities of α-particle emissions, a dosimetric methodology that accurately predicts the thresholds for organ toxicity has not been reported. This is in part due to the fact that the biological effects caused by α-particle radiation differ markedly from the effects caused by traditional external beam (photon or electron) radiation or β-particle emitting radiopharmaceuticals. The concept of relative biological effectiveness (RBE) is used to quantify the ratio of absorbed doses required to achieve a given biological response with alpha particles versus a reference radiation (typically a beta emitter or external beam radiation). However, as conventionally defined, the RBE varies as a function of absorbed dose and therefore a single RBE value is limited in its utility because it cannot be used to predict response over a wide range of absorbed doses. Therefore, efforts are underway to standardize bioeffect modeling for different fractionation schemes and dose rates for both nuclear medicine and external beam radiotherapy. Given the preponderant use of external beams of radiation compared to nuclear medicine in cancer therapy, the more clinically relevant quantity, the 2 Gy equieffective dose, EQD2(α/β), has recently been proposed by the ICRU. In concert with EQD2(α/β), we introduce a new, redefined RBE quantity, named RBE2(α/β), as the ratio of the two linear coefficients that characterize the α particle absorbed dose-response curve and the low-LET megavoltage photon 2 Gy fraction equieffective dose-response curve. The theoretical framework for the proposed new formalism is presented along with its application to experimental data obtained from irradiation of a breast cancer cell line. Radiobiological parameters are obtained using the linear quadratic model to fit cell survival data for MDA-MB-231 human breast cancer cells that were irradiated with either α particles or a single fraction of low-LET (137)Cs γ rays. From these, the linear coefficient for both the biologically effective dose (BED) and the EQD2(α/β) response lines were derived for fractionated irradiation. The standard RBE calculation, using the traditional single fraction reference radiation, gave RBE values that ranged from 2.4 for a surviving fraction of 0.82-6.0 for a surviving fraction of 0.02, while the dose-independent RBE2(4.6) value was 4.5 for all surviving fraction values. Furthermore, bioeffect modeling with RBE2(α/β) and EQD2(α/β) demonstrated the capacity to predict the surviving fraction of cells irradiated with acute and fractionated low-LET radiation, α particles and chronic exponentially decreasing dose rates of low-LET radiation. RBE2(α/β) is independent of absorbed dose for α-particle emitters and it provides a more logical framework for data reporting and conversion to equieffective dose than the conventional dose-dependent definition of RBE. Moreover, it provides a much needed foundation for the ongoing development of an α-particle dosimetry paradigm and will facilitate the use of tolerance dose data available from external beam radiation therapy, thereby helping to develop αRPT as a single modality as well as for combination therapies.

Redefining Relative Biological Effectiveness in the Context of the EQDX Formalism: Implications for Alpha-Particle Emitter Therapy.

PubMed

Hobbs, Robert F; Howell, Roger W; Song, Hong; Baechler, Sébastien; Sgouros, George

2013-12-30

Alpha-particle radiopharmaceutical therapy (αRPT) is currently enjoying increasing attention as a viable alternative to chemotherapy for targeting of disseminated micrometastatic disease. In theory, αRPT can be personalized through pre-therapeutic imaging and dosimetry. However, in practice, given the particularities of α-particle emissions, a dosimetric methodology that accurately predicts the thresholds for organ toxicity has not been reported. This is in part due to the fact that the biological effects caused by α-particle radiation differ markedly from the effects caused by traditional external beam (photon or electron) radiation or β-particle emitting radiopharmaceuticals. The concept of relative biological effectiveness (RBE) is used to quantify the ratio of absorbed doses required to achieve a given biological response with alpha particles versus a reference radiation (typically a beta emitter or external beam radiation). However, as conventionally defined, the RBE varies as a function of absorbed dose and therefore a single RBE value is limited in its utility because it cannot be used to predict response over a wide range of absorbed doses. Therefore, efforts are underway to standardize bioeffect modeling for different fractionation schemes and dose rates for both nuclear medicine and external beam radiotherapy. Given the preponderant use of external beams of radiation compared to nuclear medicine in cancer therapy, the more clinically relevant quantity, the 2 Gy equieffective dose, EQD2(α/β), has recently been proposed by the ICRU. In concert with EQD2(α/β), we introduce a new, redefined RBE quantity, named RBE2(α/β), as the ratio of the two linear coefficients that characterize the α particle absorbed dose-response curve and the low-LET megavoltage photon 2 Gy fraction equieffective dose-response curve. The theoretical framework for the proposed new formalism is presented along with its application to experimental data obtained from irradiation of a breast cancer cell line. Radiobiological parameters are obtained using the linear quadratic model to fit cell survival data for MDA-MB-231 human breast cancer cells that were irradiated with either α particles or a single fraction of low-LET 137 Cs γ rays. From these, the linear coefficient for both the biologically effective dose (BED) and the EQD2(α/β) response lines were derived for fractionated irradiation. The standard RBE calculation, using the traditional single fraction reference radiation, gave RBE values that ranged from 2.4 for a surviving fraction of 0.82-6.0 for a surviving fraction of 0.02, while the dose-independent RBE2(4.6) value was 4.5 for all surviving fraction values. Furthermore, bioeffect modeling with RBE2(α/β) and EQD2(α/β) demonstrated the capacity to predict the surviving fraction of cells irradiated with acute and fractionated low-LET radiation, α particles and chronic exponentially decreasing dose rates of low-LET radiation. RBE2(α/β) is independent of absorbed dose for α-particle emitters and it provides a more logical framework for data reporting and conversion to equieffective dose than the conventional dose-dependent definition of RBE. Moreover, it provides a much needed foundation for the ongoing development of an α-particle dosimetry paradigm and will facilitate the use of tolerance dose data available from external beam radiation therapy, thereby helping to develop αRPT as a single modality as well as for combination therapies.

Effect of Temporal Pattern of Radiation in Intensity Modulated Radiotherapy on Cell Cycle Progression and Apoptosis of ACHN Renal Cell Carcinoma Cell Line.

PubMed

Khorramizadeh, Maryam; Saberi, Alihossein; Tahmasebi-Birgani, Mohammadjavad; Shokrani, Parvaneh; Amouhedari, Alireza

The existence of a hypersensitive radiation response to doses below 1 Gy is well established for many normal and tumor cell lines. The aim of this study was to ascertain the impact of temporal pattern modeling IMRT on survival, cell cycle and apoptosis of human RCC cell line ACHN, so as to provide radiobiological basis for optimizing IMRT plans for this disease. The ACHN renal cell carcinoma cell line was used in this study. Impact of the triangle, V, small-large or large-small temporal patterns in the presence and absence of threshold dose of hyper-radiosensitivity at the beginning of patterns were studied using soft agarclonogenic assays. Cell cycle and apoptosis analysis were performed after irradiation with the temporal patterns. For triangle and small-large dose sequences, survival fraction was significantly reduced after irradiation with or without threshold dose of hyper-radiosensitivity at the beginning of the patterns. In all of the dose patterns, cell cycle distributions and the percentage of apoptotic cells at 24 h after irradiation with or without priming dose of hyper-radiosensitivity showed no significant difference. However, apoptotic cells were increased when beams with the smallest dose applied at the beginning of dose pattern like triangle and small-large dose sequence. These data show that the biologic effects of single fraction may differ in clinical settings depending on the size and sequence of the partial fractions. Doses at the beginning but not at the end of sequences may change cytotoxicity effects of radiation.

Endothelial-derived interleukin-6 induces cancer stem cell motility by generating a chemotactic gradient towards blood vessels.

PubMed

Kim, Hong Sun; Chen, Yu-Chih; Nör, Felipe; Warner, Kristy A; Andrews, April; Wagner, Vivian P; Zhang, Zhaocheng; Zhang, Zhixiong; Martins, Manoela D; Pearson, Alexander T; Yoon, Euisik; Nör, Jacques E

2017-11-21

Recent evidence suggests that the metastatic spread of head and neck squamous cell carcinomas (HNSCC) requires the function of cancer stem cells endowed with multipotency, self-renewal, and high tumorigenic potential. We demonstrated that cancer stem cells reside in perivascular niches and are characterized by high aldehyde dehydrogenase (ALDH) activity and high CD44 expression (ALDH high CD44 high ) in HNSCC. Here, we hypothesize that endothelial cell-secreted interleukin-6 (IL-6) contributes to tumor progression by enhancing the migratory phenotype and survival of cancer stem cells. Analysis of tissue microarrays generated from the invasive fronts of 77 HNSCC patients followed-up for up to 11 years revealed that high expression of IL-6 receptor (IL-6R) (p=0.0217) or co-receptor gp130 (p=0.0422) correlates with low HNSCC patient survival. We observed that endothelial cell-secreted factors induce epithelial to mesenchymal transition (EMT) and enhance invasive capacity of HNSCC cancer stem cells. Conditioned medium from CRISPR/Cas9-mediated IL-6 knockout primary human endothelial cells is less chemotactic for cancer stem cells in a microfluidics-based system than medium from control endothelial cells (p<0.05). Blockade of the IL-6 pathway with a humanized anti-IL-6R antibody (tocilizumab) inhibited endothelial cell-induced motility in vitro and decreased the fraction of cancer stem cells in vivo . Notably, xenograft HNSCC tumors vascularized with IL-6-knockout endothelial cells exhibited slower tumor growth and smaller cancer stem cell fraction. These findings demonstrate that endothelial cell-secreted IL-6 enhances the motility and survival of highly tumorigenic cancer stem cells, suggesting that endothelial cells can create a chemotactic gradient that enables the movement of carcinoma cells towards blood vessels.

Judgement on "hit or non-hit" of CHO cells exposed to accelerated heavy-ions (Fe- or Ar-ions) using division delay and CR-39 plastics as an indicator.

PubMed

Mehnati, P; Yatagai, F; Tsuzuki, T; Hanaoka, F; Sasaki, H

2001-03-01

The cell killing effect of ionizing radiation depends on the degree of linear energy transfer (LET). The relative biological effectiveness (RBE) reaches a maximum at LET of around 100-200 keV/micron and decreases at higher levels. The ion clusters produced by high-LET radiation are not uniformly distributed. The incidence of non-hit cell events is higher in high LET irradiation than in the cases of low-LET irradiation. This fact could explain the decrease in the cell killing effect at higher levels of LET irradiation. Since the cell killing effect may be related to the nuclear traversal of heavy-ions, it is necessary to establish methods to distinguish the hit cells from the non-hit cells, especially in case with high LET irradiation. Using time-lapse photography, we first examined the hit events by observing the division delay in the cells caused by high-LET irradiation. In addition, we explored the use of CR-39 plastics to detect the exact position of heavy-ion traversal on the surface of a flask where cells were growing. When Chinese hamster ovary (CHO-K1) cells were exposed to 4 Gy of accelerated Fe-ions (2000 keV/micron) or Ar (1640 keV/micron)-ions, the surviving fraction decreased to about 30% in both cases of irradiation. Eighty percent of the irradiated cells, suffered a division delay in contrast to the remaining 20% of the cells which showed a normal division time (12-13 hrs). The later 20% of the cells is considered to be a population of cells which were not actually traversed by heavy-ions. The difference between the higher values of the surviving fraction (approximately 30%) and the non-hit cell population (20%) indicates that some hit cells can grow even after being hit by heavy-ions. The fraction of recovered cells determined by the time-lapse photography method was 10%, and this value closely correlated with the difference between the surviving fraction and the non-hit cells. We used the Poisson distribution of the hit-events by heavy-ions among the cell population in order to calculate the fraction of cells receiving at least a single-hit in the cell nucleus (130 micron 2 in average size). From this calculation we determined that 80% of the cells had a single hit to their nuclei by a heavy-ion which induced such early cellular responses as division delay. Our finding in the experiments using CR-39 plastics as a detector for hit-sites further supported the idea that the hit lethality of a cell is related to heavy-ion traversal through its nucleus. This study indicates the possible usefulness of both the division delay and CR-39 plastic methods for evaluating the biological effects of heavy-ions, especially when these two methods are combined.

Effect of image-guided hypofractionated stereotactic radiotherapy on peripheral non-small-cell lung cancer

PubMed Central

Wang, Shu-wen; Ren, Juan; Yan, Yan-li; Xue, Chao-fan; Tan, Li; Ma, Xiao-wei

2016-01-01

The objective of this study was to compare the effects of image-guided hypofractionated radiotherapy and conventional fractionated radiotherapy on non-small-cell lung cancer (NSCLC). Fifty stage- and age-matched cases with NSCLC were randomly divided into two groups (A and B). There were 23 cases in group A and 27 cases in group B. Image-guided radiotherapy (IGRT) and stereotactic radiotherapy were conjugately applied to the patients in group A. Group A patients underwent hypofractionated radiotherapy (6–8 Gy/time) three times per week, with a total dose of 64–66 Gy; group B received conventional fractionated radiotherapy, with a total dose of 68–70 Gy five times per week. In group A, 1-year and 2-year local failure survival rate and 1-year local failure-free survival rate were significantly higher than in group B (P<0.05). The local failure rate (P<0.05) and distant metastasis rate (P>0.05) were lower in group A than in group B. The overall survival rate of group A was significantly higher than that of group B (P=0.03), and the survival rate at 1 year was 87% vs 63%, (P<0.05). The median survival time of group A was longer than that of group B. There was no significant difference in the incidence of complications between the two groups (P>0.05). Compared with conventional fractionated radiation therapy, image-guided hypofractionated stereotactic radiotherapy in NSCLC received better treatment efficacy and showed good tolerability. PMID:27574441

The influence of the oestrous cycle on the radiation response of solid tumours

NASA Astrophysics Data System (ADS)

Swann, Patricia R.

Oestrogen increases the transcription of nitric oxide synthase, thus increasing nitric oxide production, which can result in vasodilation of blood vessels. Fluctuating levels of oestrogen throughout the menstrual cycle has the potential to affect tumour blood flow. Variations of blood supply to a solid tumour can influence tumour oxygenation and subsequently the percentage of hypoxic cells. As hypoxic cells are more resistant to radiation than well-oxygenated cells, this could potentially affect the radiation response of the tumour. This project evaluated the impact of the oestrous stage on the radiation response of BCHT, RIF-1 and SCCvii tumours in syngeneic C3H mice. The oestrous cycle consists of the following stages, pro-oestrus, oestrus, metoestrus and dioestrus and each stage can be determined by the cellular composition of vaginal smears. The peak of oestrogen occurs in the ovulatory phase and a second smaller peak occurs in dioestrus. Subcutaneous tumour were treated at a volume of 200 - 250 mm3 with local irradiation of 10 Gy ionising radiation at different stages of the oestrous cycle. Tumours were excised either immediately or 24 hours after irradiation and disaggregated into a single cell suspension. Tumour cell survival was assessed by clonogenic assay of the excised tumour relative to untreated tumours excised at the corresponding oestrous stage. Tumours irradiated in oestrus consistently produced the lowest surviving fraction after immediate and delayed excision. Tumours irradiated in pro-oestrus and excised immediately after irradiation, showed a two-fold increase in surviving fraction compared to tumours irradiated in oestrus. The surviving fractions of tumours excised 24 hours after irradiation were less than for tumours excised immediately after irradiation. Surviving fractions of irradiated, clamped KHT tumours were independent of oestrous stage. To confirm that these oestrous stage dependent changes were due to changes in tumour perfusion, the degree of transient perfusion in the tumours was assessed. This used a fluorescent double-staining technique by intravenous injection of the fluorescent dyes Hoechst 33342 and diheptyloxacarbocyanine with a 20 minute interval between dye administrations. These dyes stain functional blood vessels and can be viewed under the fluorescent microscope. Regions of vasculature stained with both dyes indicate constant perfusion throughout the experiment, whereas only one dye indicates mismatch or transient perfusion. Tumour vasculature that experiences intermittent perfusion will result in areas of acute hypoxia that can impact on the radiation response of the tumour. The results shows that in oestrus, KHT and RIF-1 tumours showed the lowest proportion of transient perfusion, where as this oestrous stage produced the most mismatch perfusion in the SCCvii tumour. The metastatic spread of KHT tumour cells was influenced by the oestrous cycle. Fractionated irradiation of a primary tumour during metoestrus and dioestrus showed less tumour control by radiation when compared to tumours irradiated in oestrus. The intravenous injection of KHT tumour cells in oestrus and dioestrus also produced a less metastatic burden to the lungs than cells injected in pro-oestrus and metoestrus. The results of this project suggest that there are oestrous stage dependent effects that could alter the radiation response of tumours.

Maitake Pro4X has anti-cancer activity and prevents oncogenesis in BALBc mice.

PubMed

Roldan-Deamicis, Agustina; Alonso, Eliana; Brie, Belén; Braico, Diego Aguilera; Balogh, Gabriela Andrea

2016-09-01

The understanding of the molecular mechanisms of the immune tolerance induced by the tumoral microenvironment is fundamental to prevent cancer development or to treat cancer patients using immunotherapy. Actually, there are investigations about "addressed-drugs" against cancer cells without affecting normal cells. It could be ideal to find selective and specific compounds that only recognize and destroy tumor cells without damaging the host normal cells. For thousands of years, mushrooms have been used for medicinal purposes because of their curative properties. D-Fraction, an extract of Maitake (from the edible Grifola frondosa mushroom), rich in β-glucans, exert notable effects in the immune system. Until now, some published articles suggest that Maitake D-Fraction could have anti-tumoral activity, prevent oncogenesis and metastasis in some tumor types. However, there are no clear data about Maitake D-Fraction action on breast cancer prevention and its exact molecular mechanisms are not yet elucidated. The experiments were performed employing 25 female BALBc mice that were treated with and without Maitake D-Fraction Pro4X or Maitake Standard for 15 days by daily intraperitoneal injection. After treatment period, all mice were implanted with murine tumor cells LM3 to induce mammary tumorigenesis. Animals were checked weekly and killed after 46 days of LM3 transplant; percentage of cancer prevention, rate of tumor growing, and overall survival were determined. Under dissection, the internal organs were evaluated histologically and genetically by RT-PCR. We found that 5 mg/kg per day of Maitake D-Fraction Pro4X, administered dairy during 15 days to BALBc mice was able to block more than 60% breast cancer development. However, Maitake Standard prevents oncogenesis in 26% to respect control. In this work, we found that Maitake D-Fraction Pro4X, administered to BALBc mice, prevents breast carcinogenesis, block tumor invasiveness, reduce angiogenesis, and increase overall survival. © 2016 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.

Survival of Escherichia coli after isoelectric solubilization and precipitation of fish protein.

PubMed

Lansdowne, L R; Beamer, S; Jaczynski, J; Matak, K E

2009-07-01

Protein recovery for fish processing by-products utilizes extreme pH shifts for isoelectric solubilization and precipitation. The purpose of this study was to determine if Escherichia coli would survive exposure to the extreme pH shifts during the protein recovery process. Fresh rainbow trout were beheaded, gutted, and minced and then inoculated with approximately 10(9) CFU of E. coli ATCC 25922 per g, homogenized, and brought to the target pH of 2.0, 3.0, 11.5, or 12.5 by the addition of concentrated hydrochloric acid or sodium hydroxide to solubilize muscle proteins. The homogenate was blended and centrifuged to separate the lipid and insoluble components (bones, skin, insoluble protein, etc.) from the protein solution. The protein solution was subjected to a second pH shift (pH 5.5) resulting in protein precipitation that was recovered with centrifugation. Microbial analysis was conducted on each fraction (i.e., lipid, insoluble components, protein, and water) with selective and nonselective media. The sums of the surviving E. coli in these fractions were compared with the initial inoculum. The greatest total microbial reduction occurred when the pH was shifted to 12.5 (P < 0.05), i.e., a 4.4-log reduction of cells on nonselective media and a 6.0-log reduction of cells on selective media. The use of selective and nonselective media showed that there was significant (P < 0.05) injury sustained by cells exposed to alkaline treatment (pH 11.5 and 12.5) in all fractions except the insoluble fraction at pH 11.5. Increasing the exposure time or the pH may result in greater bacterial reductions in the recovered protein.

Intrastriatal Grafting of Chromospheres: Survival and Functional Effects in the 6-OHDA Rat Model of Parkinson's Disease

PubMed Central

Boronat-García, Alejandra; Palomero-Rivero, Marcela; Guerra-Crespo, Magdalena; Millán-Aldaco, Diana; Drucker-Colín, René

2016-01-01

Cell replacement therapy in Parkinson’s disease (PD) aims at re-establishing dopamine neurotransmission in the striatum by grafting dopamine-releasing cells. Chromaffin cell (CC) grafts produce some transitory improvements of functional motor deficits in PD animal models, and have the advantage of allowing autologous transplantation. However, CC grafts have exhibited low survival, poor functional effects and dopamine release compared to other cell types. Recently, chromaffin progenitor-like cells were isolated from bovine and human adult adrenal medulla. Under low-attachment conditions, these cells aggregate and grow as spheres, named chromospheres. Here, we found that bovine-derived chromosphere-cell cultures exhibit a greater fraction of cells with a dopaminergic phenotype and higher dopamine release than CC. Chromospheres grafted in a rat model of PD survived in 57% of the total grafted animals. Behavioral tests showed that surviving chromosphere cells induce a reduction in motor alterations for at least 3 months after grafting. Finally, we found that compared with CC, chromosphere grafts survive more and produce more robust and consistent motor improvements. However, further experiments would be necessary to determine whether the functional benefits induced by chromosphere grafts can be improved, and also to elucidate the mechanisms underlying the functional effects of the grafts. PMID:27525967

Oligodendrocyte progenitor cells proliferate and survive in an immature state following treatment with an axolemma-enriched fraction

PubMed Central

Becker-Catania, Sara G; Nelson, Julie K; Olivares, Shantel; Chen, Shu-Jen; DeVries, George H

2011-01-01

The ability of an AEF (axolemma-enriched fraction) to influence the proliferation, survival and differentiation of OPC (oligodendrocyte progenitor cells) was evaluated. Following addition of AEF to cultured OPC, the AEF associated with the outer surface of OPC so that subsequent metabolic events were likely mediated by direct AEF-OPC contact. Addition of AEF to the cultured OPC resulted in a dose- and time-dependent increase in proliferation that was partially dependent on Akt (protein kinase B) and MAPK (mitogen-activated protein kinase) activation. The major mitogen in an AEF-SE (soluble 2.0 M NaCl extract of the AEF) was identified as aFGF (acidic fibroblast growth factor) and accounted for 50% of the mitogenicity. The remaining 50% of the mitogenicity had properties consistent with bFGF (basic fibroblast growth factor) but was not unequivocally identified. Under conditions that limit the survival of OPC in culture, AEF treatment prolonged the survival of the OPC. Antigenic and morphological examination of the AEF-treated OPC indicated that the AEF treatment helped the OPC survive in a more immature state. The potential downstream metabolic pathways potentially activated in OPC by AEF and the consequences of these activated pathways are discussed. The results of these studies are consistent with the view that direct contact of axons with OPC stimulates their proliferation and survival while preventing their differentiation. PMID:21345173

Fhit-deficient normal and cancer cells are mitomycin C and UVC resistant

PubMed Central

Ottey, M; Han, S-Y; Druck, T; Barnoski, B L; McCorkell, K A; Croce, C M; Raventos-Suarez, C; Fairchild, C R; Wang, Y; Huebner, K

2004-01-01

To identify functions of the fragile tumour suppressor gene, FHIT, matched pairs of Fhit-negative and -positive human cancer cell clones, and normal cell lines established from Fhit −/− and +/+ mice, were stressed and examined for differences in cell cycle kinetics and survival. A larger fraction of Fhit-negative human cancer cells and murine kidney cells survived treatment with mitomycin C or UVC light compared to matched Fhit-positive cells; ∼10-fold more colonies of Fhit-deficient cells survived high UVC doses in clonigenic assays. The human cancer cells were synchronised in G1, released into S and treated with UVC or mitomycin C. At 18 h post mitomycin C treatment ∼6-fold more Fhit-positive than -negative cells had died, and 18 h post UVC treatment 3.5-fold more Fhit-positive cells were dead. Similar results were obtained for the murine −/− cells. After low UVC doses, the rate of DNA synthesis in −/− cells decreased more rapidly and steeply than in +/+ cells, although the Atr–Chk1 pathway appeared intact in both cell types. UVC surviving Fhit −/− cells appear transformed and exhibit >5-fold increased mutation frequency. This increased mutation burden could explain the susceptibility of Fhit-deficient cells in vivo to malignant transformation. PMID:15494723

The effects of compound danshen dripping pills and human umbilical cord blood mononuclear cell transplant after acute myocardial infarction.

PubMed

Jun, Yi; Chunju, Yuan; Qi, Ai; Liuxia, Deng; Guolong, Yu

2014-04-01

The low frequency of survival of stem cells implanted in the myocardium after acute myocardial infarction may be caused by inflammation and oxidative stress in the myocardial microenvironment. We evaluated the effects of a traditional Chinese medicine, Compound Danshen Dripping Pills, on the cardiac microenvironment and cardiac function when used alone or in combination with human umbilical cord blood mononuclear cell transplant after acute myocardial infarction. After surgically induced acute myocardial infarction, rabbits were treated with Compound Danshen Dripping Pills alone or in combination with human umbilical cord blood mononuclear cell transplant. Evaluation included histology, measurement of left ventricular ejection fraction and fractional shortening, leukocyte count, count of green fluorescent protein positive cells, superoxide dismutase activity, and malondialdehyde content. Combination treatment with Compound Danshen Dripping Pills and human umbilical cord blood mononuclear cell transplant significantly increased the survival of implanted cells, inhibited cardiac cell apoptosis, decreased oxidative stress, decreased the inflammatory response, and improved cardiac function. Rabbits treated with either Compound Danshen Dripping Pills or human umbilical cord blood mononuclear cells alone had improvement in these effects compared with untreated control rabbits. Combination therapy with Compound Danshen Dripping Pills and human umbilical cord blood mononuclear cells may improve cardiac function and morphology after acute myocardial infarction.

Transplantation of spermatogonial stem cells isolated from leukemic mice restores fertility without inducing leukemia

PubMed Central

Fujita, Kazutoshi; Ohta, Hiroshi; Tsujimura, Akira; Takao, Tetsuya; Miyagawa, Yasushi; Takada, Shingo; Matsumiya, Kiyomi; Wakayama, Teruhiko; Okuyama, Akihiko

2005-01-01

More than 70% of patients survive childhood leukemia, but chemotherapy and radiation therapy cause irreversible impairment of spermatogenesis. Although autotransplantation of germ cells holds promise for restoring fertility, contamination by leukemic cells may induce relapse. In this study, we isolated germ cells from leukemic mice by FACS sorting. The cell population in the high forward-scatter and low side-scatter regions of dissociated testicular cells from leukemic mice were analyzed by staining for MHC class I heavy chain (H-2Kb/H-2Db) and for CD45. Cells that did not stain positively for H-2Kb/H-2Db and CD45 were sorted as the germ cell–enriched fraction. The sorted germ cell–enriched fractions were transplanted into the testes of recipient mice exposed to alkylating agents. Transplanted germ cells colonized, and recipient mice survived. Normal progeny were produced by intracytoplasmic injection of sperm obtained from recipient testes. When unsorted germ cells from leukemic mice were transplanted into recipient testes, all recipient mice developed leukemia. The successful birth of offspring from recipient mice without transmission of leukemia to the recipients indicates the potential of autotransplantation of germ cells sorted by FACS to treat infertility secondary to anticancer treatment for childhood leukemia. PMID:15965502

Stereotactic Body Radiotherapy for Early-stage Non-small-cell Lung Cancer in Patients 80 Years and Older: A Multi-center Analysis.

PubMed

Cassidy, Richard J; Patel, Pretesh R; Zhang, Xinyan; Press, Robert H; Switchenko, Jeffrey M; Pillai, Rathi N; Owonikoko, Taofeek K; Ramalingam, Suresh S; Fernandez, Felix G; Force, Seth D; Curran, Walter J; Higgins, Kristin A

2017-09-01

Stereotactic body radiotherapy (SBRT) is the standard of care for medically inoperable early-stage non-small-cell lung cancer. Despite the limited number of octogenarians and nonagenarians on trials of SBRT, its use is increasingly being offered in these patients, given the aging cancer population, medical fragility, or patient preference. Our purpose was to investigate the efficacy, safety, and survival of patients ≥ 80 years old treated with definitive lung SBRT. Patients who underwent SBRT were reviewed from 2009 to 2015 at 4 academic centers. Patients diagnosed at ≥ 80 years old were included. Kaplan-Meier and multivariate logistic regression and Cox proportional hazard regression analyses were performed. Recursive partitioning analysis was done to determine a subgroup of patients most likely to benefit from therapy. A total of 58 patients were included, with a median age of 84.9 years (range, 80.1-95.2 years), a median follow-up time of 19.9 months (range, 6.9-64.9 months), a median fraction size of 10.0 Gy (range, 7.0-20.0 Gy), and a median number of fractions of 5.0 (range, 3.0-8.0 fractions). On multivariate analysis, higher Karnofsky performance status (KPS) was associated with higher local recurrence-free survival (hazard ratio [HR], 0.92; P < .01), regional recurrence-free survival (HR, 0.94; P < .01), and overall survival (HR, 0.91; P < .01). On recursive partitioning analysis, patients with KPS ≥ 75 had improved 3-year cancer-specific and overall survival (99.4% and 91.9%, respectively) compared with patients with KPS < 75 (47.8% and 23.6%, respectively; P < .01). Definitive lung SBRT for early-stage non-small-cell lung cancer was efficacious and safe in patients ≥ 80 years old. Patients with a KPS of ≥ 75 derived the most benefit from therapy. Copyright © 2017 Elsevier Inc. All rights reserved.

The combination effect of sodium butyrate and 5-Aza-2'-deoxycytidine on radiosensitivity in RKO colorectal cancer and MCF-7 breast cancer cell lines.

PubMed

Cho, Hang Joo; Kim, Sin Young; Kim, Kee Hwan; Kang, Won Kyung; Kim, Ji Il; Oh, Seong Tack; Kim, Jeong Soo; An, Chang Hyeok

2009-05-21

The overall level of chromatin compaction is an important mechanism of radiosensitivity, and modification of DNA methylation and histone deacetylation may increase radiosensitivity by altering chromatin compaction. In this study, we investigated the effect of a demethylating agent, a histone deacetylase(HDAC) inhibitor, and the two agents combined on radiosensitivity in human colon and breast cancer cell lines. In this study, we used RKO colorectal cancer cell line and MCF-7 breast cancer cell lines and normal colon cell lines. On each of the cell lines, we used three different agents: the HDAC inhibitor sodium butyrate(SB), the demethylating agent 5-Aza-2'-deoxycytidine(5-aza-DC), and radiation. We then estimated the percentage of the cell survival using the XTT method and experimented to determine if there was an augmentation in the therapeutic effect by using different combinations of the two or three of the treatment methods. After treatment of each cell lines with 5-aza-DC, SB and 6 grays of radiation, we observed that the survival fraction was lower after the treatment with 5-aza-DC or SB than with radiation alone in RKO and MCF-7 cell lines(p < 0.001). The survival fraction was lowest when the two agents, 5-aza-DC and SB were combined with radiation in both RKO and MCF-cell lines. In conclusion, 5-aza-DC and SB can enhance radiosensitivity in both MCF-7 and RKO cell lines. The combination effect of a demethylating agent and an HDAC inhibitor is more effective than that of single agent treatment in both breast and colon cancer cell lines.

Effect of Early Neonatal Exposure to Deltamethrin on the Purkinje Cell Number in Rat Cerebellum

PubMed Central

Asari, Mohd Asnizam; Abdullah, Mohammad Shukri; Abdullah, Suryati

2008-01-01

Deltamethrin is a widely used insecticide belonging to the class of pyrethroid. Although the neurotoxicity of pyrethroids including deltamethrin is well established, it is still unclear whether exposure to deltamethrin during neonatal period has any deleterious effect on the survival of the Purkinje cells in the cerebellum. In the study, we investigated the total number of Purkinje cells in experimental rats exposed to deltamethrin using a stereological method, the fractionator. Deltamethrin in a dose of 1 mg/kg/day (corresponds to 20% of LD50 ) was administered through oral gavage to male pups from 2nd to 5th postnatal day (PND). At PND 21 the animals were sacrificed and their cerebelli were removed. The cerebelli were systematically sampled using the fractionator method and stained with cresyl fast violet. The number of the Purkinje cells was counted for each cerebellum. The results showed that there was no significant difference in the total number of Purkinje cells in the deltamethrin-treated group as compared to the control animals. This suggests that deltamethrin exposure at the current dosage during the neonatal period do not have any significant effect on the survival of the Purkinje cells in the cerebellum. PMID:22570585

Effect of total hydroalcholic extract of Nigella sativa and its n-hexane and ethyl acetate fractions on ACHN and GP-293 cell lines.

PubMed

Shahraki, Samira; Khajavirad, Abolfazl; Shafei, Mohammad Naser; Mahmoudi, Mahmoud; Tabasi, Nafisa Sadat

2016-01-01

Medicinal plants are noted for their many advantages including the ability to treat diseases such as cancer. In this study, we examined the antitumor effect of the medicinal plant Nigella sativa on the morphology, survival, and apoptosis of ACHN (human renal adenocarcinoma) and GP-293 (normal renal epithelial) cell lines. From a hydroalcoholic extract of N. sativa, n-hexane and ethyl acetate fractions were extracted. Cells were treated with various concentrations of total hydroalcholic extract and n-hexane and ethyl acetate fractions; cell viability, morphological changes, and apoptosis were then determined. Results were presented as mean ± standard error of the mean (SEM). One-way analysis of variance (ANOVA) was applied for the statistical analysis of the data. The total extract and the fractions in a dose- and time-dependent manner reduced the cell viability in ACHN with no effect on the GP-293 cell line. In addition, the total extract resulted in more morphological changes in the ACHN cells compared to the GP-293 cells. The effect of the total extract in inducing apoptosis after 48 hours in the ACHN cell line was greater than in GP-293. In addition, the effect of the two fractions was lower than the total extract at all used concentrations. Therefore, the effect of total extract and n-hexane and ethyl acetate fractions of N. sativa on cell viability and apoptosis in the ACHN cell line is greater than in the GP-293 cell line. However, the effect of the total extract is higher than either of the two fractions on their own.

Monte Carlo based protocol for cell survival and tumour control probability in BNCT.

PubMed

Ye, S J

1999-02-01

A mathematical model to calculate the theoretical cell survival probability (nominally, the cell survival fraction) is developed to evaluate preclinical treatment conditions for boron neutron capture therapy (BNCT). A treatment condition is characterized by the neutron beam spectra, single or bilateral exposure, and the choice of boron carrier drug (boronophenylalanine (BPA) or boron sulfhydryl hydride (BSH)). The cell survival probability defined from Poisson statistics is expressed with the cell-killing yield, the 10B(n,alpha)7Li reaction density, and the tolerable neutron fluence. The radiation transport calculation from the neutron source to tumours is carried out using Monte Carlo methods: (i) reactor-based BNCT facility modelling to yield the neutron beam library at an irradiation port; (ii) dosimetry to limit the neutron fluence below a tolerance dose (10.5 Gy-Eq); (iii) calculation of the 10B(n,alpha)7Li reaction density in tumours. A shallow surface tumour could be effectively treated by single exposure producing an average cell survival probability of 10(-3)-10(-5) for probable ranges of the cell-killing yield for the two drugs, while a deep tumour will require bilateral exposure to achieve comparable cell kills at depth. With very pure epithermal beams eliminating thermal, low epithermal and fast neutrons, the cell survival can be decreased by factors of 2-10 compared with the unmodified neutron spectrum. A dominant effect of cell-killing yield on tumour cell survival demonstrates the importance of choice of boron carrier drug. However, these calculations do not indicate an unambiguous preference for one drug, due to the large overlap of tumour cell survival in the probable ranges of the cell-killing yield for the two drugs. The cell survival value averaged over a bulky tumour volume is used to predict the overall BNCT therapeutic efficacy, using a simple model of tumour control probability (TCP).

WE-E-BRE-10: Level of Breast Cancer Stem Cell Correlated with Tumor Radioresistence: An Indication for Individualized Breast Cancer Therapy Adapted to Cancer Stem Cell Fractions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Qi, S; Pajonk, F; McCloskey, S

2014-06-15

Purposes: The presence of cancer stem cells (CSCs) in a solid tumor could result in poor tumor control probability. The purposes are to study CSC radiosensitivity parameters α and β and their correlation to CSC levels to understand the underlying radioresistance mechanisms and enable individualized treatment design. Methods: Four established breast cancer cell lines (MCF-7, T47D, MDA-MB-231, and SUM159PT) were irradiated in vitro using single radiation doses of 0, 2, 4, 6, 8 or 10 Gy. The fractions of CSCs in each cell lines were determined using cancer stem cell markers. Mammosphere assays were also performed to better estimate themore » number of CSCs and represent the CSC repopulation in a human solid tumor. The measured cell surviving fractions were fitted using the Linear-quadratic (LQ) model with independent fitting parameters: α-TC, β-TC (TCs), α-CSC, β-CSC (CSCs), and fs (the percentage of CSCs in each sample). Results: The measured fs increased following the irradiation by MCF-7 (0.1%), T47D (0.9%), MDA-MB-231 (1.18%) and SUM159T (2.46%), while decreasing surviving curve slopes were observed, indicating greater radioresistance, in the opposite order. The fitting yielded the radiosensitive parameters for the MCF-7: α-TC=0.1±0.2Gy{sup −1}, β-TC= 0.08 ±0.14Gy{sup −2}, α-CSC=0.04±0.07Gy{sup −1}, β-CSC =0.02±0.3Gy{sup −2}; for the SUM159PT, α-TC=0.08±0.25 Gy{sup −1}, β-TC=0.02±0.02Gy{sup −2}, α-CSC=0.04±0.18Gy{sup −1}, β-CSC =0.004±0.24Gy{sup −2}. In the mammosphere assay, where fs were higher than the corresponding cell line assays, there was almost no shoulder found in the surviving curves (more radioresistant in mammosphere assays) yielding β-CSC of approximately 0. Conclusion: Breast cancer stem cells were more radioresistant characterized by smaller α and β values compared to differentiated breast cancer cells. Percentage of breast cancer stem cells strongly correlated to overall tumor radioresistance. This observation suggested the feasibility of individualized radiotherapy prescription based on the fractions of cancer stem cells found in biopsy.« less

Human papillomavirus status and the relative biological effectiveness of proton radiotherapy in head and neck cancer cells.

PubMed

Wang, Li; Wang, Xiaochun; Li, Yuting; Han, Shichao; Zhu, Jinming; Wang, Xiaofang; Molkentine, David P; Blanchard, Pierre; Yang, Yining; Zhang, Ruiping; Sahoo, Narayan; Gillin, Michael; Zhu, Xiaorong Ronald; Zhang, Xiaodong; Myers, Jeffrey N; Frank, Steven J

2017-04-01

Human papillomavirus (HPV)-positive oropharyngeal carcinomas response better to X-ray therapy (XRT) than HPV-negative disease. Whether HPV status influences the sensitivity of head and neck cancer cells to proton therapy or the relative biological effectiveness (RBE) of protons versus XRT is unknown. Clonogenic survival was used to calculate the RBE; immunocytochemical analysis and neutral comet assay were used to evaluate unrepaired DNA double-strand breaks. HPV-positive cells were more sensitive to protons and the unrepaired double-strand breaks were more numerous in HPV-positive cells than in HPV-negative cells (p < .001). Protons killed more cells than did XRT at all fraction sizes (all RBEs > 1.06). Cell line type and radiation fraction size influenced the RBE. HPV-positive cells were more sensitive to protons than HPV-negative cells maybe through the effects of HPV on DNA damage and repair. The RBE for protons depends more on cell type and fraction size than on HPV status. © 2016 Wiley Periodicals, Inc. Head Neck 39: 708-715, 2017. © 2016 Wiley Periodicals, Inc.

Ionizing Radiation Activates AMP-Activated Kinase (AMPK): A Target for Radiosensitization of Human Cancer Cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sanli, Toran; Rashid, Ayesha; Liu Caiqiong

2010-09-01

Purpose: Adenosine monophosphate (AMP)-activated kinase (AMPK) is a molecular energy sensor regulated by the tumor suppressor LKB1. Starvation and growth factors activate AMPK through the DNA damage sensor ataxia-telangiectasia mutated (ATM). We explored the regulation of AMPK by ionizing radiation (IR) and its role as a target for radiosensitization of human cancer cells. Methods and Materials: Lung, prostate, and breast cancer cells were treated with IR (2-8 Gy) after incubation with either ATM or AMPK inhibitors or the AMPK activator metformin. Then, cells were subjected to either lysis and immunoblotting, immunofluorescence microscopy, clonogenic survival assays, or cell cycle analysis. Results:more » IR induced a robust phosphorylation and activation of AMPK in all tumor cells, independent of LKB1. IR activated AMPK first in the nucleus, and this extended later into cytoplasm. The ATM inhibitor KU-55933 blocked IR activation of AMPK. AMPK inhibition with Compound C or anti-AMPK {alpha} subunit small interfering RNA (siRNA) blocked IR induction of the cell cycle regulators p53 and p21{sup waf/cip} as well as the IR-induced G2/M arrest. Compound C caused resistance to IR, increasing the surviving fraction after 2 Gy, but the anti-diabetic drug metformin enhanced IR activation of AMPK and lowered the surviving fraction after 2 Gy further. Conclusions: We provide evidence that IR activates AMPK in human cancer cells in an LKB1-independent manner, leading to induction of p21{sup waf/cip} and regulation of the cell cycle and survival. AMPK appears to (1) participate in an ATM-AMPK-p21{sup waf/cip} pathway, (2) be involved in regulation of the IR-induced G2/M checkpoint, and (3) may be targeted by metformin to enhance IR responses.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Karube, Masataka, E-mail: mstk117@gmail.com; Department of Radiology, The University of Tokyo Hospital, Tokyo; Yamamoto, Naoyoshi

Purpose: In an aging society, many senior citizens want less invasive treatment because of potential medical complications. The National Institute of Radiological Sciences has started to treat stage I lung cancer with single-fraction carbon-ion radiation therapy (CIRT) as a dose escalation prospective phase 1/2 trial. We evaluated the efficacy and safety of CIRT for patients 80 years of age and older, undergoing single-fraction CIRT. Methods and Materials: Peripheral non-small cell lung cancer patients who were treated with single-fraction CIRT were prospectively followed. We analyzed the data from among these patients 80 years of age and older. Results: There were 70 patients. Medianmore » age was 83 years (range: 80-89) and median follow-up period was 42.7 months (range: 12-128 months). Three-year local control, cause-specific survival, and overall survival rates were 88.0%, 81.6%, and 72.4%, respectively. Five-year local control, cause-specific survival, and overall survival rates were 85.8%, 64.9%, and 39.7%, respectively. There were no adverse effects higher than grade 2 either in the acute or late phase in terms of skin and lung. Analgesic agents were necessary for only 5 patients (7.1%), to relieve muscular or rib fracture pain caused by irradiation. Conclusions: Single-fraction CIRT was low-risk and effective, even for the elderly.« less

Hypofractionated Radiotherapy Is Superior to Conventional Fractionation in an Orthotopic Model of Anaplastic Thyroid Cancer.

PubMed

Oweida, Ayman; Phan, Andy; Vancourt, Benjamin; Robin, Tyler; Hararah, Mohammad K; Bhatia, Shilpa; Milner, Dallin; Lennon, Shelby; Pike, Laura; Raben, David; Haugen, Bryan; Pozdeyev, Nikita; Schweppe, Rebecca; Karam, Sana D

2018-06-01

Anaplastic thyroid cancer (ATC) is an aggressive and highly lethal disease with poor outcomes and resistance to therapy. Despite multimodality treatment, including radiation therapy and chemotherapy, response rates remain <15%, with a median time to progression of less than three months. Recent advances in radiotherapy (RT) delivery and gene-expression profiling may help guide patient selection for personalized therapy. The purpose of this study was to characterize the response to radiation in a panel of ATC cell lines and to test alternative RT fractionation schedules for overcoming radioresistance. The cellular response to radiation was characterized based on clonogenic assays. Radiation response was correlated with microarray gene-expression data. Hypofractionated and conventional RT was tested in an orthotopic ATC tumor model, and tumor growth was assayed locally and distantly with in vivo and ex vivo bioluminescence imaging. A spectrum of radiosensitivities was observed in ATC cell lines. Radioresistant cell lines had higher levels of CXCR4 compared to radiosensitive cell lines. Compared to conventionally fractionated RT, hypofractionated RT resulted in significantly improved tumor growth delay, decreased regional and distant metastases, and improved overall survival. The findings demonstrate the heterogeneity of response to radiation in ATC tumors and the superiority of hypofractionated RT in improving local control, metastatic spread, and survival in preclinical models. These data support the design of clinical trials targeting radioresistant pathways in combination with hypofractionated RT.

High Efficiency Latency and Activation of Herpes Simplex Virus in Human Cells

NASA Astrophysics Data System (ADS)

Wigdahl, Brian L.; Scheck, Adrienne C.; de Clercq, Erik; Rapp, Fred

1982-09-01

Herpes simplex virus (HSV) exists in humans in a latent form that can be activated. To characterize the molecular basis of the cell-virus interactions and to analyze the state of the latent HSV genome, an in vitro model system was established. In this system a large fraction of the latently infected cells contain an HSV genome that can be activated. Cell survival was reduced minimally after repression of high multiplicity HSV type 1 (HSV-1) infection of human fibroblast cells with (E)-5-(2-bromovinyl)-2'-deoxyuridine in combination with human leukocyte interferon (IFN-α ). A minimum of 1 to 3 percent of the surviving cells contained an HSV genome that could be activated either by human cytomegalovirus superinfection or reduction in incubation temperature.

Astrocytes produce an insulin-like neurotrophic factor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kadle, R.; Suksang, C.; Fellows, R.E.

1986-05-01

They have previously reported that survival of dissociated neurons from fetal rat telencephalon plated at low density in serum-free, hormone-free defined medium is enhanced in the presence of insulin. In the absence of insulin a similar effect on neuronal survival is observed if cells are grown in medium conditioned by glial cells. The present study was carried out to characterize the insulin-like neurotrophic activity present in the glial conditioned medium (GLCM). Conditioned medium from confluent cultures of astrogial cells maintained in a serum free defined medium without insulin was collected every two or three days. A 5 to 30kDa fractionmore » of this medium was obtained by filtering it sequentially through YM30 and YM5 membrane filters. Binding of /sup 125/I-insulin to high density neuronal cultures was inhibited 43% by this fraction. Radioimmunoassay for insulin indicated that 1-2 ng of immuno-reactive insulin were present per ml of GLCM. Immunosequestration of the factor by insulin antibodies bound to protein A agarose gel resulted in loss of neurotrophic activity of the 5 to 30 kDa fraction. These results indicate that cultured astrocytes produce a factor immunologically and biochemically similar to insulin. This factor enhances the survival of neurons in culture and may be important for their normal development and differentiation.« less

Identification of the Centrifuged Lipoaspirate Fractions Suitable for Postgrafting Survival.

PubMed

Qiu, Lihong; Su, Yingjun; Zhang, Dongliang; Song, Yajuan; Liu, Bei; Yu, Zhou; Guo, Shuzhong; Yi, Chenggang

2016-01-01

The Coleman centrifugation procedure generates fractions with different adipocyte and progenitor cell densities. This study aimed to identify all fractions that are feasible for implantation. Human lipoaspirates were processed by Coleman centrifugation. The centrifugates were divided arbitrarily into upper, middle, and lower layers. Adipocyte viability, morphology, numbers of stromal vascular fraction cells, and adipose-derived mesenchymal stem cells of each layer were determined. The 12-week volume retention of subcutaneously implanted 0.3-ml lipoasperate of each layer was investigated in an athymic mice model. Most damaged adipocytes were located in the upper layers, whereas the intact adipocytes were distributed in the middle and lower layers. A gradient of stromal vascular fraction cell density was formed in the centrifugates. The implant volume retentions of samples from the upper, middle, and lower layers were 33.44 ± 5.9, 55.11 ± 4.4, and 71.2 ± 5.8 percent, respectively. Furthermore, the middle and lower layers contained significantly more adipose-derived stem cells than did the upper layer. The lower layer contains more viable adipocytes and stromal vascular fraction cells leading to the highest implant volume retention, whereas the most impaired cells are distributed in the upper layer, leading to the least volume retention. Although with a lower stromal vascular fraction content, the middle layer has a substantial number of intact adipocytes that are capable of retaining partial adipose tissue volume after implantation, suggesting that the middle layer may be an alternative fat source when large volumes of fat grafts are needed for transplantation.

From conventionally fractionated radiation therapy to hyperfractionated radiation therapy alone and with concurrent chemotherapy in patients with early-stage nonsmall cell lung cancer.

PubMed

Jeremić, Branislav; Milicić, Biljana

2008-02-15

The authors' single-institution experience in patients with early-stage (I and II) nonsmall cell lung cancer (NSCLC) who were treated between 1980 and 1998 with either conventionally fractionated (CF) radiation therapy (RT), or hyperfractionated (HFX) RT, or HFX RT with concurrent paclitaxel/carboplatin (HFX RT-Pac/C) was reviewed. Seventy-eight patients received 60 grays (Gy) in 30 daily fractions (CF), 116 patients received 69.6 Gy (1.2 Gy twice daily), and 56 patients received 67.6 Gy (1.3 Gy twice daily) with concurrent, low-dose, daily C (25 mg/m2) and Pac (10 mg/m2). Biologically equivalent doses for the 3 groups were 72 Gy, 78 Gy, and 76 Gy, respectively, for acute effects (alpha/beta = 10 Gy) and 120 Gy, 111 Gy, and 111 Gy, respectively, for late effects (alpha/beta = 2 Gy). For all 250 patients, the overall median survival was 27 months, the cause-specific survival was 27 months, the local progression-free survival was 32 months, and distant metastasis-free survival was not achieved; and the respective 5-year survival rates were 27%, 32%, 45%, and 68%. CF achieved significantly inferior survival than either HFX RT alone or HFX RT-Pac/C (P = .0332 and P = .0013, respectively), and no difference was observed between the 2 HFX RT regimens (P = .1934). Only acute hematologic high-grade toxicity (grade >or=3) was more frequent with HFX RT-Pac/C than with either RT alone, whereas other toxicities were similar between the 3 treatment groups. HFX RT with or without concurrent chemotherapy may be better than CF in patients with early-stage NSCLC. The role of chemotherapy deserves further investigation, because the group that received chemotherapy in the current study had a higher incidence of acute high-grade hematologic toxicity. Cancer 2008. (c) 2008 American Cancer Society.

Value of Intensity-Modulated Radiotherapy in Stage IV Head-and-Neck Squamous Cell Carcinoma

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dirix, Piet, E-mail: piet.dirix@uzleuven.b; Nuyts, Sandra

2010-12-01

Purpose: To review outcome and toxicity of Stage IVa and IVb head-and-neck squamous cell carcinoma patients treated with concomitant chemotherapy and intensity-modulated radiotherapy (IMRT) according to a hybrid fractionation schedule. Methods and Materials: Between 2006 and 2008, 42 patients with Stage IV head-and-neck squamous cell carcinoma were irradiated according to a hybrid fractionation schedule consisting of 20 fractions of 2 Gy (once daily), followed by 20 fractions of 1.6 Gy (twice daily), to a total dose of 72 Gy. Chemotherapy (cisplatinum, 100mg/m{sup 2}) was administered at the start of Weeks 1 and 4. Treatment outcome and toxicity were retrospectively comparedmore » with a previous patient group (n = 55), treated according to the same schedule, but without intensity modulation. Results: Locoregional control (LRC) and overall survival were 81% and 56% after 2 years, respectively. In comparison with the previous cohort, no significant differences were observed regarding either LRC (66%, p = 0.38) or overall survival (73%, p = 0.29). No Grade 4 or 5 toxicity was reported in the IMRT group, either acute or chronic. The use of IMRT significantly reduced the incidence of late Grade 2 or 3 xerostomia (52.9% vs. 90.2%, p < 0.001). No difference was observed regarding late Grade 2 or 3 dysphagia (p = 0.66). Conclusions: Intensity-modulated chemoradiotherapy does not compromise LRC and significantly reduces late toxicity, especially regarding xerostomia.« less

Bmi-1 confers adaptive radioresistance to KYSE-150R esophageal carcinoma cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Guanyu; Liu, Luying; Sharma, Sherven

2012-08-24

Highlights: Black-Right-Pointing-Pointer Adaptive radioresistant KYSE-150R cells expressed high level of Bmi-1. Black-Right-Pointing-Pointer Bmi-1 depletion sensitized KYSE-150R cells to RT. Black-Right-Pointing-Pointer Bmi-1 depletion increased the generation of ROS in KYSE-150R cells exposed to radiation. Black-Right-Pointing-Pointer Bmi-1 depletion impaired DNA repair capacities in KYSE-150R cells exposed to radiation. -- Abstract: Radiotherapy (RT) is a major modality of cancer treatment. However, tumors often acquire radioresistance, which causes RT to fail. The exact mechanisms by which tumor cells subjected to fractionated irradiation (FIR) develop an adaptive radioresistance are largely unknown. Using the radioresistant KYSE-150R esophageal squamous cell carcinoma (ESCC) model, which was derived frommore » KYSE-150 parental cells using FIR, the role of Bmi-1 in mediating the radioadaptive response of ESCC cells to RT was investigated. The results showed that the level of Bmi-1 expression was significantly higher in KYSE-150R cells than in the KYSE-150 parental cells. Bmi-1 depletion sensitized the KYSE-150R cells to RT mainly through the induction of apoptosis, partly through the induction of senescence. A clonogenic cell survival assay showed that Bmi-1 depletion significantly decreased the radiation survival fraction in KYSE-150R cells. Furthermore, Bmi-1 depletion increased the generation of reactive oxygen species (ROS) and the expression of oxidase genes (Lpo, Noxo1 and Alox15) in KYSE-150R cells exposed to irradiation. DNA repair capacities assessed by {gamma}-H2AX foci formation were also impaired in the Bmi-1 down-regulated KYSE-150R cells. These results suggest that Bmi-1 plays an important role in tumor radioadaptive resistance under FIR and may be a potent molecular target for enhancing the efficacy of fractionated RT.« less

On the importance of prompt oxygen changes for hypofractionated radiation treatments.

PubMed

Kissick, Michael; Campos, David; van der Kogel, Albert; Kimple, Randall

2013-10-21

This discussion is motivated by observations of prompt oxygen changes occurring prior to a significant number of cancer cells dying (permanently stopping their metabolic activity) from therapeutic agents like large doses of ionizing radiation. Such changes must be from changes in the vasculature that supplies the tissue or from the metabolic changes in the tissue itself. An adapted linear-quadratic treatment is used to estimate the cell survival variation magnitudes from repair and reoxygenation from a two-fraction treatment in which the second fraction would happen prior to significant cell death from the first fraction, in the large fraction limit. It is clear the effects of oxygen changes are likely to be the most significant factor for hypofractionation because of large radiation doses. It is a larger effect than repair. Optimal dose timing should be determined by the peak oxygen timing. A call is made to prioritize near real time measurements of oxygen dynamics in tumors undergoing hypofractionated treatments in order to make these treatments adaptable and patient-specific.

Expression of EGFR Under Tumor Hypoxia: Identification of a Subpopulation of Tumor Cells Responsible for Aggressiveness and Treatment Resistance

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hoogsteen, Ilse J., E-mail: i.hoogsteen@rther.umcn.nl; Marres, Henri A.M.; Hoogen, Franciscus J.A. van den

2012-11-01

Purpose: Overexpression of epidermal growth factor receptor (EGFR) and tumor hypoxia have been shown to correlate with worse outcome in several types of cancer including head-and-neck squamous cell carcinoma. Little is known about the combination and possible interactions between the two phenomena. Methods and Materials: In this study, 45 cases of histologically confirmed squamous cell carcinomas of the head and neck were analyzed. All patients received intravenous infusions of the exogenous hypoxia marker pimonidazole prior to biopsy. Presence of EGFR, pimonidazole binding, and colocalization between EGFR and tumor hypoxia were examined using immunohistochemistry. Results: Of all biopsies examined, respectively, 91%more » and 60% demonstrated EGFR- and pimonidazole-positive areas. A weak but significant association was found between the hypoxic fractions of pimonidazole (HFpimo) and EGFR fractions (F-EGFR) and between F-EGFR and relative vascular area. Various degrees of colocalization between hypoxia and EGFR were found, increasing with distance from the vasculature. A high fraction of EGFR was correlated with better disease-free and metastasis-free survival, whereas a high degree of colocalization correlated with poor outcome. Conclusions: Colocalization of hypoxia and EGFR was demonstrated in head-and-neck squamous cell carcinomas, predominantly at longer distances from vessels. A large amount of colocalization was associated with poor outcome, which points to a survival advantage of hypoxic cells that are also able to express EGFR. This subpopulation of tumor cells might be indicative of tumor aggressiveness and be partly responsible for treatment resistance.« less

Outcome of Patients Treated With a Single-Fraction Dose of Palliative Radiation for Cutaneous T-Cell Lymphoma

DOE Office of Scientific and Technical Information (OSTI.GOV)

Thomas, Tarita O.; Agrawal, Priya; Guitart, Joan

2013-03-01

Purpose: Cutaneous T-cell lymphoma (CTCL) is a radiosensitive tumor. Presently, treatment with radiation is given in multiple fractions. The current literature lacks data that support single-fraction treatment for CTCL. This retrospective review assesses the clinical response in patients treated with a single fraction of radiation. Methods and Materials: This study reviewed the records of 58 patients with CTCL, primarily mycosis fungoides, treated with a single fraction of palliative radiation therapy (RT) between October 1991 and January 2011. Patient and tumor characteristics were reviewed. Response rates were compared using Fisher's exact test and multiple logistic regressions. Survival rates were determined usingmore » the Kaplan-Meier method. Cost-effectiveness analysis was performed to assess the cost of a single vs a multifractionated treatment regimen. Results: Two hundred seventy individual lesions were treated, with the majority (97%) treated with ≥700 cGy; mean follow-up was 41.3 months (range, 3-180 months). Response rate by lesion was assessed, with a complete response (CR) in 255 (94.4%) lesions, a partial response in 10 (3.7%) lesions, a partial response converted to a CR after a second treatment in 4 (1.5%) lesions, and no response in 1 (0.4%) lesion. The CR in lower extremity lesions was lower than in other sites (P=.0016). Lesions treated with photons had lower CR than those treated with electrons (P=.017). Patients with lesions exhibiting large cell transformation and tumor morphology had lower CR (P=.04 and P=.035, respectively). Immunophenotype did not impact response rate (P=.23). Overall survival was significantly lower for patients with Sézary syndrome (P=.0003) and erythroderma (P<.0001). The cost of multifractionated radiation was >200% higher than that for single-fraction radiation. Conclusions: A single fraction of 700 cGy-800 cGy provides excellent palliation for CTCL lesions and is cost effective and convenient for the patient.« less

Radiosensitivity of Patient-Derived Glioma Stem Cell 3-Dimensional Cultures to Photon, Proton, and Carbon Irradiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chiblak, Sara; Tang, Zili; Molecular and Translational Radiation Oncology, Heidelberg Ion Therapy Center, Heidelberg Institute of Radiation Oncology, University of Heidelberg Medical School and National Center for Tumor Diseases, German Cancer Research Center, Heidelberg

Purpose: To investigate the radiosensitivity of primary glioma stem cell (GSC) cultures with different CD133 status in a 3-dimensional (3D) model after photon versus proton versus carbon irradiation. Methods and Materials: Human primary GSC spheroid cultures were established from tumor specimens of six consented glioblastoma patients. Human U87MG was used as a classical glioblastoma radioresistant cell line. Cell suspensions were generated by mechanical dissociation of GSC spheroids and embedded in a semi-solid 3D matrix before irradiation. Spheroid-like colonies were manually counted by microscopy. Cells were also recovered and quantified by fluorescence. CD133 expression and DNA damage were evaluated by flow cytometry.more » Results: The fraction of CD133{sup +} cells varied between 0.014% and 96% in the six GSC cultures and showed a nonsignificant correlation with plating efficiency and survival fractions. The 4 most photon-radioresistant GSC cultures were NCH644, NCH421k, NCH441, and NCH636. Clonogenic survival for proton irradiation revealed relative biologic effectiveness (RBE) in the range of 0.7-1.20. However, carbon irradiation rendered the photon-resistant GSC cultures sensitive, with average RBE of 1.87-3.44. This effect was partly attributed to impaired capability of GSC to repair carbon ion–induced DNA double-strand breaks as determined by residual DNA repair foci. Interestingly, radiosensitivity of U87 cells was comparable to GSC cultures using clonogenic survival as the standard readout. Conclusions: Carbon irradiation is effective in GSC eradication with similar RBE ranges approximately 2-3 as compared with non-stem GSC cultures (U87). Our data strongly suggest further exploration of GSC using classic radiobiology endpoints such as the here-used 3D clonogenic survival assay and integration of additional GSC-specific markers.« less

Monte Carlo N-Particle (MCNP) Modeling of the Cellular Dosimetry of 64Cu: Comparison with MIRDcell S Values and Implications for Studies of Its Cytotoxic Effects.

PubMed

Cai, Zhongli; Kwon, Yongkyu Luke; Reilly, Raymond M

2017-02-01

64 Cu emits positrons as well as β - particles and Auger and internal conversion electrons useful for radiotherapy. Our objective was to model the cellular dosimetry of 64 Cu under different geometries commonly used to study the cytotoxic effects of 64 Cu. Monte Carlo N-Particle (MCNP) was used to simulate the transport of all particles emitted by 64 Cu from the cell surface (CS), cytoplasm (Cy), or nucleus (N) of a single cell; monolayer in a well (radius = 0.32-1.74 cm); or a sphere (radius = 50-6,000 μm) of cells to calculate S values. The radius of the cell and N ranged from 5 to 12 μm and 2 to 11 μm, respectively. S values were obtained by MIRDcell for comparison. MCF7/HER2-18 cells were exposed in vitro to 64 Cu-labeled trastuzumab. The subcellular distribution of 64 Cu was measured by cell fractionation. The surviving fraction was determined in a clonogenic assay. The relative differences of MCNP versus MIRDcell self-dose S values (S self ) for 64 Cu ranged from -0.2% to 3.6% for N to N (S N←N ), 2.3% to 8.6% for Cy to N (S N←Cy ), and -12.0% to 7.3% for CS to N (S N←CS ). The relative differences of MCNP versus MIRDcell cross-dose S values were 25.8%-30.6% for a monolayer and 30%-34% for a sphere, respectively. The ratios of S N←N versus S N←Cy and S N←Cy versus S N←CS decreased with increasing ratio of the N of the cell versus radius of the cell and the size of the monolayer or sphere. The surviving fraction of MCF7 /: HER2-18 cells treated with 64 Cu-labeled trastuzumab (0.016-0.368 MBq/μg, 67 nM) for 18 h versus the absorbed dose followed a linear survival curve with α = 0.51 ± 0.05 Gy -1 and R 2 = 0.8838. This is significantly different from the linear quadratic survival curve of MCF7 /: HER2-18 cells exposed to γ-rays. MCNP- and MIRDcell-calculated S values agreed well. 64 Cu in the N increases the dose to the N in isolated single cells but has less effect in a cell monolayer or small cluster of cells simulating a micrometastasis, and little effect in a sphere analogous to a tumor xenograft compared with 64 Cu in the Cy or on the CS. The dose deposited by 64 Cu is less effective for cell killing than γ-rays. © 2017 by the Society of Nuclear Medicine and Molecular Imaging.

Purification of fetal mouse hepatoblasts by magnetic beads coated with monoclonal anti-e-cadherin antibodies and their in vitro culture.

PubMed

Nitou, Miho; Sugiyama, Yoshinori; Ishikawa, Katsutoshi; Shiojiri, Nobuyoshi

2002-10-01

A simple, rapid, and reproducible method of fetal hepatoblast purification was established to investigate mechanisms controlling interactions between hepatoblasts and nonparenchymal cells during liver development. Because E-cadherin is exclusively expressed on the cell membrane of hepatoblasts, magnetic beads coated with monoclonal antibodies to an extracellular epitope of its molecule were used to purify hepatoblasts from a cell suspension prepared from 12.5-day fetal mouse livers. The purity and yield in the hepatoblast fraction prepared in our protocol were more than 90% and approximately 30%, respectively. The nonparenchymal fraction rarely contained hepatoblasts; the rate of hepatoblast contamination in this fraction was less than 1%. Separate cultures of these two fractions were compared with cocultures of both fractions. In culture of the hepatoblast fraction, hepatoblasts formed aggregates similar to a bunch of grapes via their loose adhesion, floating in the medium after 24 h, and dissociated into single cells from the aggregates after 120 h of culture. By contrast, in the mixed culture, the majority of hepatoblasts formed multicellular spheroids after 24 h, and these spheroids changed into monolayer cell sheets after 120 h of culture. The cells comprising these monolayer sheets abundantly expressed albumin and carbamoylphosphate synthase I. In the mixed culture, fibroblastic cells also proliferated extensively with spreading on glass slides and surrounded the hepatoblast or hepatocyte colonies. On the other hand, fibroblastic cells spreading on glass slides decreased gradually in cultures of the nonparenchymal cell fraction alone. These findings indicated that the coexistence of hepatoblasts and nonparenchymal cells may be essential for their mutual survival, proliferation, differentiation, and morphogenesis. The conditioned medium of fetal liver cell cultures could partially replace the effects of the nonparenchymal cells on hepatoblasts in vitro. Our isolation protocol for fetal mouse hepatoblasts using immunobeads can greatly facilitate studies on mechanisms of cell-cell interactions during liver development.

Prediction of cellular radiosensitivity from DNA damage induced by gamma-rays and carbon ion irradiation in canine tumor cells.

PubMed

Wada, Seiichi; Van Khoa, Tran; Kobayashi, Yasuhiko; Funayama, Tomoo; Ogihara, Kikumi; Ueno, Shunji; Ito, Nobuhiko

2005-11-01

Diseases of companion animals are shifting from infectious diseases to neoplasms (cancer), and since radiation therapy is one of the effective choices available for cancer treatment, the application of radiotherapy in veterinary medicine is likely to increase. However tumor tissues have different radiosensitivities, and therefore it is important to determine the intrinsic radiosensitivity of tumors in individual patients in advance of radiotherapy. We have studied the relationship between the surviving cell fraction measured by a clonogenic assay and DNA double strand breaks detected by a comet assay under neutral conditions in three canine tumor cell lines, after gamma-ray and carbon ion irradiation. In all the cell lines, cell death assessed by the clonogenic assay was much higher following irradiation with carbon ions than with gamma-rays. The initial and residual (4 hr) DNA damage due to gamma-ray and carbon ion irradiation were higher in a radiosensitive cell line than in a radioresistant cell line. The surviving cell fraction at 2 Gy (SF2) showed a tendency for correlation with both the initial and residual DNA damage. In particular, the residual damage per Gy was significantly correlated with SF2, regardless of the type of radiation. This indicates that cellular radiosensitivity can be predicted by detection of radiation-induced residual DNA damage.

In vitro toxicity of welding fumes and their constituents

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stern, R.M.; Hansen, K.; Madsen, A.F.

1988-08-01

Welding fumes from a wide variety of processes and applications were assayed for toxicity with BHK21 cell line and SHE primary cells in culture. The most toxic fumes are those from the manual metal arc welding of stainless steel (MMA/SS) (LD50 = 7-14 microgram/ml), although all other welding fumes tested are toxic, with potencies lower by a factor of 10-200. The activity of MMA/SS is presumably due to the presence of high concentrations of Cr(VI) in the soluble fraction: For all other fumes the lowered activity (LD50 = 80-800 microgram/ml) is limited mostly to the insoluble fraction, and in partmore » can be related to the presence of MnO/sub 2/ and Fe/sub 3/O/sub 4/ which are toxic at such levels in these cell culture assays. Slight discrepancies between survival tests for the two cell lines, and between survival and lactate dehydrogenate release for BHK, indicate a differential response to certain constituents of these complex materials. These results suggest the need for a battery of different types of assays for use in an eventual ranking of exposures for the purpose of relative risk assessment.« less

Dose and Fractionation in Radiation Therapy of Curative Intent for Non-Small Cell Lung Cancer: Meta-Analysis of Randomized Trials

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ramroth, Johanna; Cutter, David J.; Darby, Sarah C.

Purpose: The optimum dose and fractionation in radiation therapy of curative intent for non-small cell lung cancer remains uncertain. We undertook a published data meta-analysis of randomized trials to examine whether radiation therapy regimens with higher time-corrected biologically equivalent doses resulted in longer survival, either when given alone or when given with chemotherapy. Methods and Materials: Eligible studies were randomized comparisons of 2 or more radiation therapy regimens, with other treatments identical. Median survival ratios were calculated for each comparison and pooled. Results: 3795 patients in 25 randomized comparisons of radiation therapy dose were studied. The median survival ratio, highermore » versus lower corrected dose, was 1.13 (95% confidence interval [CI] 1.04-1.22) when radiation therapy was given alone and 0.83 (95% CI 0.71-0.97) when it was given with concurrent chemotherapy (P for difference=.001). In comparisons of radiation therapy given alone, the survival benefit increased with increasing dose difference between randomized treatment arms (P for trend=.004). The benefit increased with increasing dose in the lower-dose arm (P for trend=.01) without reaching a level beyond which no further survival benefit was achieved. The survival benefit did not differ significantly between randomized comparisons where the higher-dose arm was hyperfractionated and those where it was not. There was heterogeneity in the median survival ratio by geographic region (P<.001), average age at randomization (P<.001), and year trial started (P for trend=.004), but not for proportion of patients with squamous cell carcinoma (P=.2). Conclusions: In trials with concurrent chemotherapy, higher radiation therapy doses resulted in poorer survival, possibly caused, at least in part, by high levels of toxicity. Where radiation therapy was given without chemotherapy, progressively higher radiation therapy doses resulted in progressively longer survival, and no upper dose level was found above which there was no further benefit. These findings support the consideration of further radiation therapy dose escalation trials, making use of modern treatment methods to reduce toxicity.« less

A comparative study of mixture cure models with covariate

NASA Astrophysics Data System (ADS)

Leng, Oh Yit; Khalid, Zarina Mohd

2017-05-01

In survival analysis, the survival time is assumed to follow a non-negative distribution, such as the exponential, Weibull, and log-normal distributions. In some cases, the survival time is influenced by some observed factors. The absence of these observed factors may cause an inaccurate estimation in the survival function. Therefore, a survival model which incorporates the influences of observed factors is more appropriate to be used in such cases. These observed factors are included in the survival model as covariates. Besides that, there are cases where a group of individuals who are cured, that is, not experiencing the event of interest. Ignoring the cure fraction may lead to overestimate in estimating the survival function. Thus, a mixture cure model is more suitable to be employed in modelling survival data with the presence of a cure fraction. In this study, three mixture cure survival models are used to analyse survival data with a covariate and a cure fraction. The first model includes covariate in the parameterization of the susceptible individuals survival function, the second model allows the cure fraction to depend on covariate, and the third model incorporates covariate in both cure fraction and survival function of susceptible individuals. This study aims to compare the performance of these models via a simulation approach. Therefore, in this study, survival data with varying sample sizes and cure fractions are simulated and the survival time is assumed to follow the Weibull distribution. The simulated data are then modelled using the three mixture cure survival models. The results show that the three mixture cure models are more appropriate to be used in modelling survival data with the presence of cure fraction and an observed factor.

Can Drugs Enhance Hypofractionated Radiotherapy? A Novel Method of Modeling Radiosensitization Using In Vitro Data

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ohri, Nitin; Dicker, Adam P.; Lawrence, Yaacov Richard, E-mail: yaacovla@gmail.com

2012-05-01

Purpose: Hypofractionated radiotherapy (hRT) is being explored for a number of malignancies. The potential benefit of giving concurrent chemotherapy with hRT is not known. We sought to predict the effects of combined modality treatments by using mathematical models derived from laboratory data. Methods and Materials: Data from 26 published clonogenic survival assays for cancer cell lines with and without the use of radiosensitizing chemotherapy were collected. The first three data points of the RT arm of each assay were used to derive parameters for the linear quadratic (LQ) model, the multitarget (MT) model, and the generalized linear quadratic (gLQ) model.more » For each assay and model, the difference between the predicted and observed surviving fractions at the highest tested RT dose was calculated. The gLQ model was fitted to all the data from each RT cell survival assay, and the biologically equivalent doses in 2-Gy fractions (EQD2s) of clinically relevant hRT regimens were calculated. The increase in cell kill conferred by the addition of chemotherapy was used to estimate the EQD2 of hRT along with a radiosensitizing agent. For comparison, this was repeated using conventionally fractionated RT regimens. Results: At a mean RT dose of 8.0 Gy, the average errors for the LQ, MT, and gLQ models were 1.63, 0.83, and 0.56 log units, respectively, favoring the gLQ model (p < 0.05). Radiosensitizing chemotherapy increased the EQD2 of hRT schedules by an average of 28% to 82%, depending on disease site. This increase was similar to the gains predicted for the addition of chemotherapy to conventionally fractionated RT. Conclusions: Based on published in vitro assays, the gLQ equation is superior to the LQ and MT models in predicting cell kill at high doses of RT. Modeling exercises demonstrate that significant increases in biologically equivalent dose may be achieved with the addition of radiosensitizing agents to hRT. Clinical study of this approach is warranted.« less

The radiation biology of the thyroid.

PubMed

Malone, J F

1975-10-01

The structure and function of the thyroid gland are described. A detailed analysis of population kinetics in the gland suggests a method of measuring cell survival after irradiation that has many features in common with methods used in other mammalian cell systems. This method is used to obtain survival curves for thyroid cells afer irradiation. The effects on survival of splitting the radiation dose into two or multiple fractions, radiation type, and radioprotective agents are also examined. In the light of these data the tolerance of thyroid tissue to radiation exposure under various conditions is discussed. The dosimetry and biological effects of 125I and 131I are described in detail, and compared with X-rays. Radioiodine treatment of thyrotoxicosis is presented in relation to the known biological effects of the isotopes on the gland. Carcinogenic action of ionizing radiations in the thyroid are reviewed with particular reference to the clinical consequences of observations in this field.

The Effect of Biologically Effective Dose and Radiation Treatment Schedule on Overall Survival in Stage I Non-Small Cell Lung Cancer Patients Treated With Stereotactic Body Radiation Therapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stahl, John M.; Ross, Rudi; Harder, Eileen M.

Purpose: To determine the effect of biologically effective dose (BED{sub 10}) and radiation treatment schedule on overall survival (OS) in patients with early-stage non-small cell lung cancer (NSCLC) undergoing stereotactic body radiation therapy (SBRT). Methods and Materials: Using data from 65 treatment centers in the United States, we retrospectively reviewed the records of T1-2 N0 NSCLC patients undergoing SBRT alone from 2006 to 2014. Biologically relevant covariates, including dose per fraction, number of fractions, and time between fractions, were used to quantify BED{sub 10} and radiation treatment schedule. The linear-quadratic equation was used to calculate BED{sub 10} and to generatemore » a dichotomous dose variable of <105 Gy versus ≥105 Gy BED{sub 10}. The primary outcome was OS. We used the Kaplan-Meier method, the log–rank test, and Cox proportional hazards regression with propensity score matching to determine whether prescription BED{sub 10} was associated with OS. Results: We identified 747 patients who met inclusion criteria. The median BED{sub 10} was 132 Gy, and 59 (7.7%) had consecutive-day fractions. Median follow-up was 41 months, and 452 patients (60.5%) had died by the conclusion of the study. The 581 patients receiving ≥105 Gy BED{sub 10} had a median survival of 28 months, whereas the 166 patients receiving <105 Gy BED{sub 10} had a median survival of 22 months (log–rank, P=.01). Radiation treatment schedule was not a significant predictor of OS on univariable analysis. After adjusting for T stage, sex, tumor histology, and Eastern Cooperative Oncology Group performance status, BED{sub 10} ≥105 Gy versus <105 Gy remained significantly associated with improved OS (hazard ratio 0.78, 95% confidence interval 0.62-0.98, P=.03). Propensity score matching on imbalanced variables within high- and low-dose cohorts confirmed a survival benefit with higher prescription dose. Conclusions: We found that dose escalation to 105 Gy BED{sub 10} and beyond may improve survival in NSCLC patients treated with SBRT.« less

Cytotoxic effect of Alpinia scabra (Blume) Náves extracts on human breast and ovarian cancer cells

PubMed Central

2013-01-01

Background Alpinia scabra, locally known as 'Lengkuas raya’, is an aromatic, perennial and rhizomatous herb from the family Zingiberaceae. It is a wild species which grows largely on mountains at moderate elevations in Peninsular Malaysia, but it can also survive in the lowlands like in the states of Terengganu and Northern Johor. The present study reports the cytotoxic potential of A. scabra extracts from different parts of the plant. Methods The experimental approach in the present study was based on a bioassay-guided fractionation. The crude methanol and fractionated extracts (hexane, chloroform and water) from different parts of A. scabra (leaves, rhizomes, roots and pseudo stems) were prepared prior to the cytotoxicity evaluation against human ovarian (SKOV-3) and hormone-dependent breast (MCF7) carcinoma cells. The identified cytotoxic extracts were then subjected to chemical investigations in order to identify the active ingredients. A normal human lung fibroblast cell line (MRC-5) was used to determine the specificity for cancerous cells. The cytotoxic extracts and fractions were also subjected to morphological assessment, DNA fragmentation analysis and DAPI nuclear staining. Results The leaf (hexane and chloroform) and rhizome (chloroform) extracts showed high inhibitory effect against the tested cells. Ten fractions (LC1-LC10) were yielded after purification of the leaf chloroform extract. Fraction LC4 which showed excellent cytotoxic activity was further purified and resulted in 17 sub-fractions (VLC1-VLC17). Sub-fraction VLC9 showed excellent cytotoxicity against MCF7 and SKOV-3 cells but not toxic against normal MRC-5 cells. Meanwhile, eighteen fractions (RC1-RC18) were obtained after purification of the rhizome chloroform extract, of which fraction RC5 showed cytotoxicity against SKOV-3 cells with high selectivity index. There were marked morphological changes when observed using phase-contrast inverted microscope, DAPI nuclear staining and also DNA fragmentations in MCF7 and SKOV-3 cells after treatment with the cytotoxic extracts and fractions which were indicative of cell apoptosis. Methyl palmitate and methyl stearate were identified in the hexane leaf extract by GC-MS analysis. Conclusions The data obtained from the current study demonstrated that the cell death induced by cytotoxic extracts and fractions of A. scabra may be due to apoptosis induction which was characterized by apoptotic morphological changes and DNA fragmentation. The active ingredients in the leaf sub-fraction VLC9 and rhizome fraction RC5 may lead to valuable compounds that have the ability to kill cancer cells but not normal cells. PMID:24215354

Impact of Adding Concomitant Chemotherapy to Hyperfractionated Accelerated Radiotherapy for Advanced Head-and-Neck Squamous Cell Carcinoma

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nuyts, Sandra; Dirix, Piet; Clement, Paul M.J.

2009-03-15

Purpose: To evaluate the feasibility and efficacy of a hyperfractionated accelerated radiotherapy (RT) schedule combined with concomitant chemotherapy (Cx) in patients with locally advanced head-and-neck squamous cell carcinoma. Methods and Materials: Between 2004 and 2007, a total of 90 patients with locoregionally advanced head-and-neck squamous cell carcinoma underwent irradiation according to a hybrid fractionation schedule consisting of 20 fractions of 2 Gy (once daily) followed by 20 fractions of 1.6 Gy (twice daily) to a total dose of 72 Gy. Concomitant Cx (cisplatinum 100 mg/m{sup 2}) was administered at the start of Weeks 1 and 4. Treatment outcome and toxicitymore » were retrospectively compared with a previous patient group (n = 73) treated with the same schedule, but without concomitant Cx, between 2001 and 2004. Results: The locoregional control (LRC) rate was 70% after 2 years. Two-year overall and 2-year disease-free survival rates were 74% and 60%, respectively. In comparison with the RT-only group, an improvement of 15% in both LRC (p = 0.03) and overall survival (p = 0.09) was observed. All patients were treated to full radiation dose according to protocol, although the Cx schedule had to be adjusted in 12 patients. No acute Grade 4 or 5 toxicity was seen, but incidences of Grade 3 acute mucositis (74.5% vs. 50.7%; p = 0.002) and dysphagia (82.2% vs. 47.9%; p < 0.001) were significantly higher in the chemoradiotherapy group compared with patients treated with RT alone. Conclusion: With this chemoradiotherapy regimen, excellent LRC and survival rates were achieved, with acceptable acute toxicity.« less

Optimization of the temporal pattern of applied dose for a single fraction of radiation: Implications for radiation therapy

NASA Astrophysics Data System (ADS)

Altman, Michael B.

The increasing prevalence of intensity modulated radiation therapy (IMRT) as a treatment modality has led to a renewed interest in the potential for interaction between prolonged treatment time, as frequently associated with IMRT, and the underlying radiobiology of the irradiated tissue. A particularly relevant aspect of radiobiology is cell repair capacity, which influences cell survival, and thus directly relates to the ability to control tumors and spare normal tissues. For a single fraction of radiation, the linear quadratic (LQ) model is commonly used to relate the radiation dose to the fraction of cells surviving. The LQ model implies a dependence on two time-related factors which correlate to radiobiological effects: the duration of radiation application, and the functional form of how the dose is applied over that time (the "temporal pattern of applied dose"). Although the former has been well studied, the latter has not. Thus, the goal of this research is to investigate the impact of the temporal pattern of applied dose on the survival of human cells and to explore how the manipulation of this temporal dose pattern may be incorporated into an IMRT-based radiation therapy treatment planning scheme. The hypothesis is that the temporal pattern of applied dose in a single fraction of radiation can be optimized to maximize or minimize cell kill. Furthermore, techniques which utilize this effect could have clinical ramifications. In situations where increased cell kill is desirable, such as tumor control, or limiting the degree of cell kill is important, such as the sparing of normal tissue, temporal sequences of dose which maximize or minimize cell kill (temporally "optimized" sequences) may provide greater benefit than current clinically used radiation patterns. In the first part of this work, an LQ-based modeling analysis of effects of the temporal pattern of dose on cell kill is performed. Through this, patterns are identified for maximizing cell kill for a given radiation pattern by concentrating the highest doses in the middle of a fraction (a "Triangle" pattern), or minimizing cell kill by placing the highest doses near the beginning and end (a "V-shaped" pattern). The conditions under which temporal optimization effects are most acute are also identified: irradiation of low alpha/beta tissues, long fraction durations, and high doses/fx. An in vitro study is then performed which verifies that the temporal effects and trends predicted by the modeling study are clearly manifested in human cells. Following this a phantom which could allow similar in vitro radiobiological experiments in a 3-dimensional clinically-based environment is designed, created, and dosimetrically assessed using TLDs, film, and biological assay-based techniques. The phantom is found to be a useful and versatile tool for such experiments. A scheme for utilizing the phantom in a clinical treatment environment is then developed. This includes a demonstration of prototype methods for optimizing the temporal pattern of applied dose in clinical IMRT plans to manipulate tissue-dependent effects. Looking toward future experimental validation of such plans using the phantom, an analysis of the suitability of biological assays for use in phantom-based in vitro experiments is performed. Finally, a discussion is provided about the steps necessary to integrate temporal optimization into in vivo experiments and ultimately into a clinical radiation therapy environment. If temporal optimization is ultimately shown to have impact in vivo, the successful implementation of the methods developed in this study could enhance the efficacy and care of thousands of patients receiving radiotherapy.

The role of phosphatidylserine in recognition and removal of erythrocytes.

PubMed

Kuypers, F A; de Jong, K

2004-03-01

During the time that erythrocytes (RBC) spend in the circulation, a series of progressive events take place that lead to their removal and determine their apparent aging and limited survival. In addition, a fraction of RBC precursors will be removed during erythropoiesis by apoptotic processes, often described as "ineffective erythropoiesis". Both will determine the survival of erythroid cells and play an important role in red cell pathology, including hemoglobinopathies and red cell membrane disorders. The loss of phospholipid asymmetry, and the exposure of phosphatidylserine (PS) on the surface of plasma membranes may be a general trigger by which cells, including aging RBC and apoptotic cells, are removed. Oxidant stress and inactivation of the system that maintains phospholipid asymmetry play a central role in the events that will lead to PS exposure, death and removal.

Tetrakis(p-carboranylthio-tetrafluorophenyl)chlorin (TPFC): application for photodynamic therapy and boron neutron capture therapy.

PubMed

Hiramatsu, Ryo; Kawabata, Shinji; Tanaka, Hiroki; Sakurai, Yoshinori; Suzuki, Minoru; Ono, Koji; Miyatake, Shin-ichi; Kuroiwa, Toshihiko; Hao, Erhong; Vicente, M Graça H

2015-03-01

Carboranyl-containing chlorins have emerged as promising dual sensitizers for use in both photodynamic therapy (PDT) and boron neutron capture therapy (BNCT), by virtue of their known tumor affinity, low cytotoxicity in dark conditions, and their strong absorptions in the red region of the optical spectrum. Tetrakis(p-carboranylthio-tetrafluorophenyl)chlorin (TPFC) is a new synthetic carboranyl-containing chlorin of high boron content (24% by weight). To evaluate TPFC's applicability as sensitizer for both PDT and BNCT, we performed an in vitro and in vivo study using F98 rat glioma cells and F98 rat glioma-bearing brain tumor models. For the in vivo BNCT study, we used boronophenylalanine (BPA), which is currently used in clinical BNCT studies, via intravenous administration (i.v.) and/or used TPFC via convection-enhanced delivery (CED), a method for local drug infusion directly into the brain. In the in vitro PDT study, the cell surviving fraction following laser irradiation (9 J/cm(2) ) was 0.035 whereas in the in vitro BNCT study, the cell surviving fraction following neutron irradiation (thermal neutron = 1.73 × 10(12) n/cm(2) ) was 0.04. In the in vivo BNCT study, the median survival time following concomitant administration of BPA (i.v.) and TPFC (CED) was 42 days (95% confidence interval; 37-43 days). © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association.

Tetrakis(p-Carboranylthio-Tetrafluorophenyl)Chlorin (TPFC): Application for Photodynamic Therapy and Boron Neutron Capture Therapy

PubMed Central

HIRAMATSU, RYO; KAWABATA, SHINJI; TANAKA, HIROKI; SAKURAI, YOSHINORI; SUZUKI, MINORU; ONO, KOJI; MIYATAKE, SHIN-ICHI; KUROIWA, TOSHIHIKO; HAO, ERHONG; VICENTE, M. GRAÇA H.

2015-01-01

Carboranyl-containing chlorins have emerged as promising dual sensitizers for use in both photodynamic therapy (PDT) and boron neutron capture therapy (BNCT), by virtue of their known tumor affinity, low cytotoxicity in dark conditions, and their strong absorptions in the red region of the optical spectrum. Tetrakis(p-carboranylthio-tetrafluorophenyl)chlorin (TPFC) is a new synthetic carboranyl-containing chlorin of high boron content (24% by weight). To evaluate TPFC’s applicability as sensitizer for both PDT and BNCT, we performed an in vitro and in vivo study using F98 rat glioma cells and F98 rat glioma-bearing brain tumor models. For the in vivo BNCT study, we used boronophenylalanine (BPA), which is currently used in clinical BNCT studies, via intravenous administration (i.v.) and/or used TPFC via convection-enhanced delivery (CED), a method for local drug infusion directly into the brain. In the in vitro PDT study, the cell surviving fraction following laser irradiation (9 J/cm2) was 0.035 whereas in the in vitro BNCT study, the cell surviving fraction following neutron irradiation (thermal neutron = 1.73 × 1012 n/cm2) was 0.04. In the in vivo BNCT study, the median survival time following concomitant administration of BPA (i.v.) and TPFC (CED) was 42 days (95% confidence interval; 37–43 days). PMID:25546823

Comparison of the outcomes of stereotactic body radiotherapy and surgery in elderly patients with cT1-2N0M0 non-small cell lung cancer.

PubMed

Nakagawa, Tatsuo; Negoro, Yoshiharu; Matsuoka, Tomoaki; Okumura, Norihito; Dodo, Yoshihiro

2014-07-01

This study aimed to compare the outcomes of stereotactic body radiotherapy (SBRT) and surgery in elderly patients with cT1-2N0M0 non-small cell lung cancer (NSCLC). Elderly patients (≥75 years) with cT1-2 (≤5 cm) N0M0 NSCLC who were treated with SBRT (n=35) or surgery (n=183) between January 2001 and December 2011 were analyzed. The following radiation doses were administered: 48 Gy/4-6 fractions in 12 patients; 50 Gy/4-5 fractions in 20; and 60 Gy/8 fractions in 3. The following surgical methods were performed: pneumonectomy in 2 patients, lobectomy in 154, segmentectomy in 23, and wedge resection in 4. Patients in the SBRT group had a higher mean age, a worse performance status, and a lower percentage of forced expiratory volume in 1.0 s than those in the surgery group. The overall 5-year survival rates were 43.8% and 67.6% for the SBRT and surgery groups, respectively (p=0.057, log-rank test). Regarding tumor diameter, patients in the surgery group survived significantly longer than did those in the SBRT group (>20-mm tumors, p=0.027; >30-mm tumors p=0.043), whereas survival did not differ significantly between the groups for ≤20-mm tumors (p=0.982). Multivariate analysis confirmed the improved survival in the surgery group compared to the SBRT group for all tumors (p=0.034) and for >20-mm tumors (p=0.016). Post-therapeutic survival among elderly patients might be better with surgery than with SBRT in NSCLC patients with tumors >20 mm. Copyright © 2014 The Japanese Respiratory Society. Published by Elsevier B.V. All rights reserved.

Targeting survival pathways to create infarct-spanning bridges of human embryonic stem cell-derived cardiomyocytes.

PubMed

Luo, Jun; Weaver, Matthew S; Dennis, James E; Whalen, Elizabeth; Laflamme, Michael A; Allen, Margaret D

2014-12-01

Generating myocyte grafts that bridge across infarcts could maximize their functional impact and best utilize small numbers of stem cells. To date, however, graft survival within acute infarcts has not been feasible. To enhance intrainfarct graft viability, human embryonic stem cell-derived cardiomyocytes (hESC-CMs) were pretreated before implantation with cobalt protoporphyrin (CoPP), a pharmacologic inducer of cytoprotective heme oxygenase-1. After preculturing with CoPP (vs phosphate-buffered saline), hESC-CMs were injected intramyocardially into acutely infarcted rat hearts, using directed injections to span the infarct. A further group received CoPP-pretreated hESC-CMs plus 4 weekly doses of systemic CoPP to prolong exposure to cytoprotectants. Two control groups with infarcts received vehicle-only intramyocardial injections or weekly systemic CoPP without cell therapy. Postinfarct ventricular function was gauged by echocardiography and graft size quantified at 8 weeks by histomorphometry. CoPP-preconditioned hESC-CMs formed stable grafts deep within infarcted myocardium, while grafts without CoPP exposure survived mainly at the infarct periphery. Fractional shortening was improved at 4 and 8 weeks in all hearts receiving cell therapies (P < .01 vs vehicle-only injections). CoPP treatment of both graft hESC-CMs and recipient animals resulted in the largest grafts, highest fractional shortening, preserved wall thickness, and reduced infarct dimensions. Cellular therapy delivered acutely after infarction significantly improved postinfarct ventricular function at 1 and 2 months. CoPP pretreatment of cells resulted in stable hESC-CM grafts within infarcted myocardium. This design enables construction of directionally oriented, infarct-spanning bands of new cardiomyocytes that might further improve functional restoration as engrafted myocytes proliferate and mature. Copyright © 2014 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.

SU-F-T-685: Evaluation of Tumor Hypoxic Fraction Using Serial Volumetric Imaging During Radiation Therapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chvetsov, A

Purpose: To develop a tumor response model which could be uses to compute tumor hypoxic fraction using serial volumetric tumor imaging. This algorithm may be used for treatment response assessment and also for guidance of more expensive PET imaging of hypoxia. Methods: Previously developed two-level cell population tumor response model was modified to include a third cell level describing hypoxic and necrotic cells. This third level was considered constant value during radiotherapy treatment; therefore, inclusion additional parameter did not compromise stability of model fitting to imaging data. Fitting the model to serial volumetric imaging data was performed using a leastmore » squares objective function and simulated annealing algorithm. The problem of reconstruction of radiobiological parameters from serial imaging data was considered as inverse ill-posed problem described by the Fredholm integral equation of the first kind. Variational regularization was used to stabilize solutions. Results: To evaluate performance of the algorithm, we used a set of serial CT imaging data on tumor-volume for 14 head and neck cancer patients. The hypoxic fractions were reconstructed for each patient and the distribution of hypoxic fractions was compared to the distribution of initial hypoxic fractions previously measured using histograph. The measured and reconstructed from imaging data distributions of hypoxic fractions are in good agreement. The reconstructed distribution of cell surviving fraction was also in better agreement with in vitro data than previously obtained using the two-level cell population model. Conclusion: Our results indicate that it is possible to evaluate the initial hypoxic tumor fraction using serial volumetric imaging and a tumor response model. This algorithm can be used for treatment response assessment and guidance of more expensive PET imaging.« less

Morphometrics of cellular damage in mice testis receiving X-ray and high-energy particle irradiation

NASA Technical Reports Server (NTRS)

Sapp, Walter J.

1987-01-01

Murine tests were exposed to single, low doses of either X-ray, helium, or argon radiation. Animals were sacrificed seventy-two hours later. Testes were fixed for transmission electron microscopy (TEM) and sectioned at either 60 nm for TEM observation or at 2 micron for counting using routine light microscope methods. Counts of the total population of surviving spermatogonia, including all type A cells, intermediate, and type B cells, were taken from tubule cross sections identified as Stage 6 and Stage 1 according to spermatogonial configuration. The surviving fraction of spermatogonia as compared to control, S/S sub o, was calculated for each dose. For both ions and X-rays, there was a rapid decline in survival at dose levels of .10 to .15 Gy in Stage 6 tubules. This was followed by a more gradual decrease in population. At higher doses, 0.30 Gy for argon and 0.80 Gy for helium and X-rays, the cell survival rates declined rapidly. Pre-leptotene spermatocytes in Stage 1 tubules exhibited a different survival curve indicating the extreme radio-sensitivity of type B spermatogonia. Data verify that the seminiferous tubules are composed of a heterogeneous population of cells with different radio-sensitivities and that these differences are manifested even at very low doses.

TH-E-BRF-06: Kinetic Modeling of Tumor Response to Fractionated Radiotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhong, H; Gordon, J; Chetty, I

2014-06-15

Purpose: Accurate calibration of radiobiological parameters is crucial to predicting radiation treatment response. Modeling differences may have a significant impact on calibrated parameters. In this study, we have integrated two existing models with kinetic differential equations to formulate a new tumor regression model for calibrating radiobiological parameters for individual patients. Methods: A system of differential equations that characterizes the birth-and-death process of tumor cells in radiation treatment was analytically solved. The solution of this system was used to construct an iterative model (Z-model). The model consists of three parameters: tumor doubling time Td, half-life of dying cells Tr and cellmore » survival fraction SFD under dose D. The Jacobian determinant of this model was proposed as a constraint to optimize the three parameters for six head and neck cancer patients. The derived parameters were compared with those generated from the two existing models, Chvetsov model (C-model) and Lim model (L-model). The C-model and L-model were optimized with the parameter Td fixed. Results: With the Jacobian-constrained Z-model, the mean of the optimized cell survival fractions is 0.43±0.08, and the half-life of dying cells averaged over the six patients is 17.5±3.2 days. The parameters Tr and SFD optimized with the Z-model differ by 1.2% and 20.3% from those optimized with the Td-fixed C-model, and by 32.1% and 112.3% from those optimized with the Td-fixed L-model, respectively. Conclusion: The Z-model was analytically constructed from the cellpopulation differential equations to describe changes in the number of different tumor cells during the course of fractionated radiation treatment. The Jacobian constraints were proposed to optimize the three radiobiological parameters. The developed modeling and optimization methods may help develop high-quality treatment regimens for individual patients.« less

Investigating the Implications of a Variable RBE on Proton Dose Fractionation Across a Clinical Pencil Beam Scanned Spread-Out Bragg Peak

DOE Office of Scientific and Technical Information (OSTI.GOV)

Marshall, Thomas I.; Chaudhary, Pankaj; Michaelidesová, Anna

2016-05-01

Purpose: To investigate the clinical implications of a variable relative biological effectiveness (RBE) on proton dose fractionation. Using acute exposures, the current clinical adoption of a generic, constant cell killing RBE has been shown to underestimate the effect of the sharp increase in linear energy transfer (LET) in the distal regions of the spread-out Bragg peak (SOBP). However, experimental data for the impact of dose fractionation in such scenarios are still limited. Methods and Materials: Human fibroblasts (AG01522) at 4 key depth positions on a clinical SOBP of maximum energy 219.65 MeV were subjected to various fractionation regimens with an interfractionmore » period of 24 hours at Proton Therapy Center in Prague, Czech Republic. Cell killing RBE variations were measured using standard clonogenic assays and were further validated using Monte Carlo simulations and parameterized using a linear quadratic formalism. Results: Significant variations in the cell killing RBE for fractionated exposures along the proton dose profile were observed. RBE increased sharply toward the distal position, corresponding to a reduction in cell sparing effectiveness of fractionated proton exposures at higher LET. The effect was more pronounced at smaller doses per fraction. Experimental survival fractions were adequately predicted using a linear quadratic formalism assuming full repair between fractions. Data were also used to validate a parameterized variable RBE model based on linear α parameter response with LET that showed considerable deviations from clinically predicted isoeffective fractionation regimens. Conclusions: The RBE-weighted absorbed dose calculated using the clinically adopted generic RBE of 1.1 significantly underestimates the biological effective dose from variable RBE, particularly in fractionation regimens with low doses per fraction. Coupled with an increase in effective range in fractionated exposures, our study provides an RBE dataset that can be used by the modeling community for the optimization of fractionated proton therapy.« less

The rat red blood cell proteome is altered by priming with 2-butoxyethanol

DOE Office of Scientific and Technical Information (OSTI.GOV)

Palkar, Prajakta S.; Kakhniashvili, David G.; Goodman, Steven R.

2008-08-01

Administration of a low priming dose of 2-butoxyethanol (BE, 500 mg/kg, p.o.) 7 days prior to a larger LD{sub 90} dose (1500 mg BE/kg, p.o.) offers protection against the lethal dose-induced hemolysis and death in female Sprague Dawley rats because of prompt and efficient replacement of red blood cells (RBCs) with new resilient RBCs. The objective of the present work was to analyze the altered proteome of RBCs upon priming with BE in order to identify the potential anti-hemolytic survival proteins induced in the primed rat RBCs (P-RBCs) as opposed to vehicle-treated RBCs (V-RBCs). The RBCs from the two groupsmore » were fractionated into membrane and cytosolic fractions. The cytosolic fractions were further fractionated for proteomic analysis into 3 fractions. The fractions were labeled with Cy3 and Cy5 fluorescent dyes and subjected to 2-dimensional differential gel electrophoresis (DIGE) to analyze the protein profiles. Seven membrane and 8 cytosolic proteins were found to be significantly increased ({>=} 2.5 fold) in P-RBCs as compared to V-RBCs. The identified proteins can be classified into antioxidant, membrane skeleton, protein turnover, lipid raft, and energy metabolism components. Increased levels of the proteins from antioxidant and membrane skeleton groups were confirmed by Western blot analysis. The study provides the first report on protein profiling of rat RBCs as well as on alteration of the proteome upon exposure to a priming dose of hemotoxicant. Further studies are needed to prove the protective role of the identified proteins and will initiate the field of survival/protective/anti-hemolytic proteins in RBCs.« less

Exposure to 60% oxygen promotes migration and upregulates angiogenesis factor secretion in breast cancer cells.

PubMed

Crowley, Peter D; Stuttgen, Vivian; O'Carroll, Emma; Ash, Simon A; Buggy, Donal J; Gallagher, Helen C

2017-01-01

Peri-operative factors, including anaesthetic drugs and techniques, may affect cancer cell biology and clinical recurrence. In breast cancer cells, we demonstrated that sevoflurane promotes migration and angiogenesis in high fractional oxygen but not in air. Follow-up analysis of the peri-operative oxygen fraction trial found an association between high inspired oxygen during cancer surgery and reduced tumor-free survival. Here we evaluated effects of acute, high oxygen exposure on breast cancer cell viability, migration and secretion of angiogenesis factors in vitro . MDA-MB-231 and MCF-7 breast cancer cells were exposed to 21%, 30%, 60%, or 80% v/v O 2 for 3 hours. Cell viability at 24 hours was determined by MTT and migration at 24 hours with the Oris™ Cell Migration Assay. Secretion of angiogenesis factors at 24 hours was measured via membrane-based immunoarray. Exposure to 30%, 60% or 80% oxygen did not affect cell viability. Migration of MDA-MB-231 and MCF-7 cells was increased by 60% oxygen ( P = 0.012 and P = 0.007, respectively) while 30% oxygen increased migration in MCF-7 cells ( P = 0.011). These effects were reversed by dimethyloxaloylglycine. In MDA-MB-231 cells high fractional oxygen increased secretion of angiogenesis factors monocyte chemotactic protein 1, regulated on activation normal T-cell expressed and vascular endothelial growth factor. In MCF-7 cells, interleukin-8, angiogenin and vascular endothelial growth factor secretion was significantly increased by high fractional oxygen. High oxygen exposure stimulates migration and secretion of angiogenesis factors in breast cancer cells in vitro .

Analysis of radiation therapy in a model of triple-negative breast cancer brain metastasis.

PubMed

Smart, DeeDee; Garcia-Glaessner, Alejandra; Palmieri, Diane; Wong-Goodrich, Sarah J; Kramp, Tamalee; Gril, Brunilde; Shukla, Sudhanshu; Lyle, Tiffany; Hua, Emily; Cameron, Heather A; Camphausen, Kevin; Steeg, Patricia S

2015-10-01

Most cancer patients with brain metastases are treated with radiation therapy, yet this modality has not yet been meaningfully incorporated into preclinical experimental brain metastasis models. We applied two forms of whole brain radiation therapy (WBRT) to the brain-tropic 231-BR experimental brain metastasis model of triple-negative breast cancer. When compared to sham controls, WBRT as 3 Gy × 10 fractions (3 × 10) reduced the number of micrometastases and large metastases by 87.7 and 54.5 %, respectively (both p < 0.01); whereas a single radiation dose of 15 Gy × 1 (15 × 1) was less effective, reducing metastases by 58.4 % (p < 0.01) and 47.1 % (p = 0.41), respectively. Neuroinflammation in the adjacent brain parenchyma was due solely to a reaction from metastases, and not radiotherapy, while adult neurogenesis in brains was adversely affected following both radiation regimens. The nature of radiation resistance was investigated by ex vivo culture of tumor cells that survived initial WBRT ("Surviving" cultures). The Surviving cultures surprisingly demonstrated increased radiosensitivity ex vivo. In contrast, re-injection of Surviving cultures and re-treatment with a 3 × 10 WBRT regimen significantly reduced the number of large and micrometastases that developed in vivo, suggesting a role for the microenvironment. Micrometastases derived from tumor cells surviving initial 3 × 10 WBRT demonstrated a trend toward radioresistance upon repeat treatment (p = 0.09). The data confirm the potency of a fractionated 3 × 10 WBRT regimen and identify the brain microenvironment as a potential determinant of radiation efficacy. The data also nominate the Surviving cultures as a potential new translational model for radiotherapy.

Metastatic potential of tumor-initiating cells in solid tumors.

PubMed

Adhikari, Amit S; Agarwal, Neeraj; Iwakuma, Tomoo

2011-01-01

The lethality of cancer is mainly caused by its properties of metastasis, drug resistance, and subsequent recurrence. Understanding the mechanisms governing these properties and developing novel strategies to overcome them will greatly improve the survival of cancer patients. Recent findings suggest that tumors are comprised of heterogeneous cell populations, and only a small fraction of these are tumorigenic with the ability to self-renew and produce phenotypically diverse tumor cell populations. Cells in this fraction are called tumor-initiating cells (TICs) or cancer stem cells (CSCs). TICs have been identified from many types of cancer. They share several similarities with normal adult stem cells including sphere-forming ability, self-renewability, and expression of stem cell surface markers and transcription factors. TICs have also been proposed to be responsible for cancer metastasis, however, scarce evidence for their metastatic potential has been provided. In this review article, we have attempted to summarize the studies which have examined the metastatic potential of TICs in solid tumors.

An Expanded Multi-scale Monte Carlo Simulation Method for Personalized Radiobiological Effect Estimation in Radiotherapy: a feasibility study

NASA Astrophysics Data System (ADS)

Zhang, Ying; Feng, Yuanming; Wang, Wei; Yang, Chengwen; Wang, Ping

2017-03-01

A novel and versatile “bottom-up” approach is developed to estimate the radiobiological effect of clinic radiotherapy. The model consists of multi-scale Monte Carlo simulations from organ to cell levels. At cellular level, accumulated damages are computed using a spectrum-based accumulation algorithm and predefined cellular damage database. The damage repair mechanism is modeled by an expanded reaction-rate two-lesion kinetic model, which were calibrated through replicating a radiobiological experiment. Multi-scale modeling is then performed on a lung cancer patient under conventional fractionated irradiation. The cell killing effects of two representative voxels (isocenter and peripheral voxel of the tumor) are computed and compared. At microscopic level, the nucleus dose and damage yields vary among all nucleuses within the voxels. Slightly larger percentage of cDSB yield is observed for the peripheral voxel (55.0%) compared to the isocenter one (52.5%). For isocenter voxel, survival fraction increase monotonically at reduced oxygen environment. Under an extreme anoxic condition (0.001%), survival fraction is calculated to be 80% and the hypoxia reduction factor reaches a maximum value of 2.24. In conclusion, with biological-related variations, the proposed multi-scale approach is more versatile than the existing approaches for evaluating personalized radiobiological effects in radiotherapy.

Biological responses of human solid tumor cells to X-ray irradiation within a 1.5-Tesla magnetic field generated by a magnetic resonance imaging-linear accelerator.

PubMed

Wang, Li; Hoogcarspel, Stan Jelle; Wen, Zhifei; van Vulpen, Marco; Molkentine, David P; Kok, Jan; Lin, Steven H; Broekhuizen, Roel; Ang, Kie-Kian; Bovenschen, Niels; Raaymakers, Bas W; Frank, Steven J

2016-10-01

Devices that combine magnetic resonance imaging with linear accelerators (MRL) represent a novel tool for MR-guided radiotherapy. However, whether magnetic fields (MFs) generated by these devices affect the radiosensitivity of tumors is unknown. We investigated the influence of a 1.5-T MF on cell viability and radioresponse of human solid tumors. Human head/neck cancer and lung cancer cells were exposed to single or fractionated 6-MV X-ray radiation; effects of the MF on cell viability were determined by cell plating efficiency and on radioresponsiveness by clonogenic cell survival. Doses needed to reduce the fraction of surviving cells to 37% of the initial value (D0s) were calculated for multiple exposures to MF and radiation. Results were analyzed using Student's t-tests. Cell viability was no different after single or multiple exposures to MRL than after exposure to a conventional linear accelerator (Linac, without MR-generated MF) in 12 of 15 experiments (all P > 0.05). Single or multiple exposures to MF had no influence on cell radioresponse (all P > 0.05). Cells treated up to four times with an MRL or a Linac further showed no changes in D0s with MF versus without MF (all P > 0.05). In conclusion, MF within the MRL does not seem to affect in vitro tumor radioresponsiveness as compared with a conventional Linac. Bioelectromagnetics. 37:471-480, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Atorvastatin prolongs the lifespan of radiation‑induced reactive oxygen species in PC-3 prostate cancer cells to enhance the cell killing effect.

PubMed

Yu, Hao; Sun, Shao-Qian; Gu, Xiao-Bin; Wang, Wen; Gao, Xian-Shu

2017-04-01

Studies have reported that atorvastatin (ATO) may increase the radiosensitivity of malignant cells. However, the influence of ATO on reactive oxygen species (ROS) levels before and after irradiation has not been fully illustrated. In the present study, radiosensitivity was evaluated by a clonogenic assay and a cell survival curve and cell apoptosis was measured by flow cytometry. ROS were detected by a laser scanning confocal microscope and flow cytometry with a DCFH-DA probe. NADPH oxidases (NOXs) and superoxide dismutase (SOD) proteins were detected by immunoblotting, and total SOD activity was measured using an SOD kit. We also conducted transient transfection of NOX2 and NOX4 genes to increase intracellular ROS generation and applied SOD mimetic tempol to enhance ROS elimination ability. Our results demonstrated that, with ATO-alone treatment, the survival fractions of irradiated PC-3 cells were significantly decreased. Meanwhile, the apoptosis rate of the irradiated cells increased significantly (P<0.05). The ROS levels of the study group decreased obviously before irradiation (P<0.01), however, the radiation-induced ROS of the study group was at a high level even when irradiation had been terminated for 2 h (P<0.01). Moreover, NOX2 and NOX4 levels and total SOD activity decreased (P<0.01), while the levels of SOD1 were stably maintained (P>0.05). On the other hand, the decreased survival fractions and high radiation-induced ROS levels were abrogated by increasing the level of NOXs by gene transfection or by enhancing the ability of SOD utilizing the addition of tempol. In conclusion, ATO enhanced the cell killing effect of irradiation by reducing endogenous ROS levels and prolonging the lifespan of radiation‑induced ROS via a decrease in the level of NOXs and SOD activity.

Neuropharmacological and neuroprotective activities of some metabolites produced by cell suspension culture of Waltheria americana Linn.

PubMed

Mundo, Jorge; Villeda-Hernández, Juana; Herrera-Ruiz, Maribel; Gutiérrez, María Del Carmen; Arellano-García, Jesús; León-Rivera, Ismael; Perea-Arango, Irene

2017-10-01

Waltheria americana is a plant used in Mexican traditional medicine to treat some nervous system disorders. The aims of the present study were to isolate and determine the neuropharmacological and neurprotective activities of metabolites produced by a cell suspension culture of Waltheria americana. Submerged cultivation of W. americana cells provided biomass. A methanol-soluble extract (WAsc) was obtained from biomass. WAsc was fractionated yielding the chromatographic fractions 4WAsc-H 2 O and WAsc-CH 2 Cl 2 . For the determination of anticonvulsant activity in vivo, seizures were induced in mice by pentylenetetrazol (PTZ). Neuropharmacological activities (release of gamma amino butyric acid (GABA) and neuroprotection) of chromatographic fractions were determined by in vitro histological analysis of brain sections of mice post mortem. Fraction 4WAsc-H 2 O (containing saccharides) did not produce neuronal damage, neurodegeneration, interstitial tissue edema, astrocytic activation, nor cell death. Pretreatment of animals with 4WAsc-H 2 O and WAsc-CH 2 Cl 2 from W. americana cell suspensions induced an increase in: GABA release, seizure latency, survival time, neuroprotection, and a decrease in the degree of severity of tonic/tonic-clonic convulsions, preventing PTZ-induced death of up to 100% of animals of study. Bioactive compounds produced in suspension cell culture of W. americana produce neuroprotective and neuropharmacological activities associated with the GABAergic neurotransmission system. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

In vitro effects of tetraiodothyroacetic acid combined with X-irradiation on basal cell carcinoma cells.

PubMed

Leith, John T; Davis, Paul J; Mousa, Shaker A; Hercbergs, Aleck A

2017-02-16

We investigated radiosensitization in an untreated basal cell carcinoma (TE.354.T) cell line and post-pretreatment with tetraiodothyroacetic acid (tetrac) X 1 h at 37°C, 0.2 and 2.0 µM tetrac. Radioresistant TE.354.T cells were grown in modified medium containing fibroblast growth factor-2, stem cell factor-1 and a reduced calcium level. We also added reproductively inactivated (30 Gy) "feeder cells" to the medium. The in vitro doubling time was 34.1 h, and the colony forming efficiency was 5.09 percent. These results were therefore suitable for clonogenic radiation survival assessment. The 250 kVp X-ray survival curve of control TE.354.T cells showed linear-quadratic survival parameters of α X-ray = 0.201 Gy -1 and β X-ray = 0.125 Gy -2 . Tetrac concentrations of either 0.2 or 2.0 µM produced α X-ray and β X-ray parameters of 2.010 and 0.282 Gy -1 and 2.050 and 0.837 Gy -2 , respectively. The surviving fraction at 2 Gy (SF 2 ) for control cells was 0.581, while values for 0.2 and 2.0 µM tetrac were 0.281 and 0.024. The SF 2 data show that tetrac concentrations of 0.2 and 2.0 µM sensitize otherwise radioresistant TE.354.T cells by factors of 2.1 and 24.0, respectively. Thus, radioresistant basal cell carcinoma cells may be radiosensitized pharmacologically by exposure to tetrac.

Sensitization of cervix cancer cells to Adriamycin by Pentoxifylline induces an increase in apoptosis and decrease senescence.

PubMed

Bravo-Cuellar, Alejandro; Ortiz-Lazareno, Pablo C; Lerma-Diaz, Jose M; Dominguez-Rodriguez, Jorge R; Jave-Suarez, Luis F; Aguilar-Lemarroy, Adriana; del Toro-Arreola, Susana; de Celis-Carrillo, Ruth; Sahagun-Flores, Jose E; de Alba-Garcia, Javier E Garcia; Hernandez-Flores, Georgina

2010-05-19

Chemotherapeutic drugs like Adriamycin (ADR) induces apoptosis or senescence in cancer cells but these cells often develop resistance and generate responses of short duration or complete failure. The methylxantine drug Pentoxifylline (PTX) used routinely in the clinics setting for circulatory diseases has been recently described to have antitumor properties. We evaluated whether pretreatment with PTX modifies apoptosis and senescence induced by ADR in cervix cancer cells. HeLa (HPV 18+), SiHa (HPV 16+) cervix cancer cells and non-tumorigenic immortalized HaCaT cells (control) were treated with PTX, ADR or PTX + ADR. The cellular toxicity of PTX and survival fraction were determinated by WST-1 and clonogenic assay respectively. Apoptosis, caspase activation and ADR efflux rate were measured by flow cytometry, senescence by microscopy. IkappaBalpha and DNA fragmentation were determinated by ELISA. Proapoptotic, antiapoptotic and senescence genes, as well as HPV-E6/E7 mRNA expression, were detected by time real RT-PCR. p53 protein levels were assayed by Western blot. PTX is toxic (WST-1), affects survival (clonogenic assay) and induces apoptosis in cervix cancer cells. Additionally, the combination of this drug with ADR diminished the survival fraction and significantly increased apoptosis of HeLa and SiHa cervix cancer cells. Treatments were less effective in HaCaT cells. We found caspase participation in the induction of apoptosis by PTX, ADR or its combination. Surprisingly, in spite of the antitumor activity displayed by PTX, our results indicate that methylxantine, per se does not induce senescence; however it inhibits senescence induced by ADR and at the same time increases apoptosis. PTX elevates IkappaBalpha levels. Such sensitization is achieved through the up-regulation of proapoptotic factors such as caspase and bcl family gene expression. PTX and PTX + ADR also decrease E6 and E7 expression in SiHa cells, but not in HeLa cells. p53 was detected only in SiHa cells treated with ADR. PTX is a good inducer of apoptosis but does not induce senescence. Furthermore, PTX reduced the ADR-induced senescence and increased apoptosis in cervix cancer cells.

Sensitization of cervix cancer cells to Adriamycin by Pentoxifylline induces an increase in apoptosis and decrease senescence

PubMed Central

2010-01-01

Background Chemotherapeutic drugs like Adriamycin (ADR) induces apoptosis or senescence in cancer cells but these cells often develop resistance and generate responses of short duration or complete failure. The methylxantine drug Pentoxifylline (PTX) used routinely in the clinics setting for circulatory diseases has been recently described to have antitumor properties. We evaluated whether pretreatment with PTX modifies apoptosis and senescence induced by ADR in cervix cancer cells. Methods HeLa (HPV 18+), SiHa (HPV 16+) cervix cancer cells and non-tumorigenic immortalized HaCaT cells (control) were treated with PTX, ADR or PTX + ADR. The cellular toxicity of PTX and survival fraction were determinated by WST-1 and clonogenic assay respectively. Apoptosis, caspase activation and ADR efflux rate were measured by flow cytometry, senescence by microscopy. IκBα and DNA fragmentation were determinated by ELISA. Proapoptotic, antiapoptotic and senescence genes, as well as HPV-E6/E7 mRNA expression, were detected by time real RT-PCR. p53 protein levels were assayed by Western blot. Results PTX is toxic (WST-1), affects survival (clonogenic assay) and induces apoptosis in cervix cancer cells. Additionally, the combination of this drug with ADR diminished the survival fraction and significantly increased apoptosis of HeLa and SiHa cervix cancer cells. Treatments were less effective in HaCaT cells. We found caspase participation in the induction of apoptosis by PTX, ADR or its combination. Surprisingly, in spite of the antitumor activity displayed by PTX, our results indicate that methylxantine, per se does not induce senescence; however it inhibits senescence induced by ADR and at the same time increases apoptosis. PTX elevates IκBα levels. Such sensitization is achieved through the up-regulation of proapoptotic factors such as caspase and bcl family gene expression. PTX and PTX + ADR also decrease E6 and E7 expression in SiHa cells, but not in HeLa cells. p53 was detected only in SiHa cells treated with ADR. Conclusion PTX is a good inducer of apoptosis but does not induce senescence. Furthermore, PTX reduced the ADR-induced senescence and increased apoptosis in cervix cancer cells. PMID:20482878

Comprehensive analysis of venom from the scorpion Centruroides tecomanus reveals compounds with antimicrobial, cytotoxic, and insecticidal activities.

PubMed

Valdez-Velazquéz, L L; Romero-Gutierrez, M T; Delgado-Enciso, I; Dobrovinskaya, O; Melnikov, V; Quintero-Hernández, V; Ceballos-Magaña, S G; Gaitan-Hinojosa, M A; Coronas, F I; Puebla-Perez, A M; Zamudio, F; De la Cruz-García, I; Vázquez-Vuelvas, O F; Soriano-Hernandez, A D; Possani, L D

2016-08-01

Centruroides tecomanus is a medically important scorpion of the state of Colima (Mexico). This communication reports the identification of venom components of this scorpion with biological activity over insects/crickets (Acheta domestica), crustaceans/fresh water shrimps (Cambarellus montezumae), and mammalians/mice (Mus musculus, strain CD1). It also describes the pharmacological effects on cell lines in culture (L5178Y cells, HeLa cells, HuTu cells and Jurkat E6-1 cells), as well as on several types of bacteria (see below). The soluble venom of this scorpion was fractionated by high-performance liquid chromatography (HPLC) and collected separately in twelve independent fractions collected over 60 min run (5 min time apart each other). The HPLC components of fraction VII were lethal to all three species used for assay. The IVth fraction had a toxic effect on freshwater shrimps. In this species, fractions VI, VII and VIII were all lethal. For crickets, fractions V and VI were toxic and fraction VII was lethal. In mouse, the lethal components were found in fraction VII, whereas fraction VIII was toxic, but not lethal, at the doses assayed. The molecular weight of peptides from the various group of fractions were identified by mass spectrometry determination. Components lethal to mice showed molecular weights from 7013 to 7487 Da. Two peptides were obtained in homogeneous form and shown to be lethal to the three species of animal used for assay. The soluble venom tested on L5178Y cell line survival was shown to be cytotoxic, at 10-100 μg/mL concentration, when compared to control murine splenocytes (p = 0.007). The soluble venom applied to Hela, Hutu and Jurkat cell lines did not show cytotoxic effects at these concentrations. On the contrary, it seems to have a proliferative effect. However the HPLC fractions I, III, VI and XII do have a cytotoxic effect on Jurkat E06-1 cells in culture at 200 μg/mL concentration. The antimicrobial activity of the venom fractions on Staphylococcus aureus (gram-positive), Escherichia coli, Pseudomonas aeruginosa y Salmonella spp (gram-negative) was measured, using the liquid inhibition growth system. The four strains of bacteria used were susceptible to fractions III and IV, affecting all four bacterial strains at concentrations below 5 μg/mL. Copyright © 2016 Elsevier Ltd. All rights reserved.

Applying a Hypoxia-Incorporating TCP Model to Experimental Data on Rat Sarcoma

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ruggieri, Ruggero, E-mail: ruggieri.ruggero@gmail.com; Stavreva, Nadejda; Naccarato, Stefania

2012-08-01

Purpose: To verify whether a tumor control probability (TCP) model which mechanistically incorporates acute and chronic hypoxia is able to describe animal in vivo dose-response data, exhibiting tumor reoxygenation. Methods and Materials: The investigated TCP model accounts for tumor repopulation, reoxygenation of chronic hypoxia, and fluctuating oxygenation of acute hypoxia. Using the maximum likelihood method, the model is fitted to Fischer-Moulder data on Wag/Rij rats, inoculated with rat rhabdomyosarcoma BA1112, and irradiated in vivo using different fractionation schemes. This data set is chosen because two of the experimental dose-response curves exhibit an inverse dose behavior, which is interpreted as duemore » to reoxygenation. The tested TCP model is complex, and therefore, in vivo cell survival data on the same BA1112 cell line from Reinhold were added to Fischer-Moulder data and fitted simultaneously with a corresponding cell survival function. Results: The obtained fit to the combined Fischer-Moulder-Reinhold data was statistically acceptable. The best-fit values of the model parameters for which information exists were in the range of published values. The cell survival curves of well-oxygenated and hypoxic cells, computed using the best-fit values of the radiosensitivities and the initial number of clonogens, were in good agreement with the corresponding in vitro and in situ experiments of Reinhold. The best-fit values of most of the hypoxia-related parameters were used to recompute the TCP for non-small cell lung cancer patients as a function of the number of fractions, TCP(n). Conclusions: The investigated TCP model adequately describes animal in vivo data exhibiting tumor reoxygenation. The TCP(n) curve computed for non-small cell lung cancer patients with the best-fit values of most of the hypoxia-related parameters confirms previously obtained abrupt reduction in TCP for n < 10, thus warning against the adoption of severely hypofractionated schedules.« less

Modeling Dynamics of Cell-to-Cell Variability in TRAIL-Induced Apoptosis Explains Fractional Killing and Predicts Reversible Resistance

PubMed Central

Bertaux, François; Stoma, Szymon; Drasdo, Dirk; Batt, Gregory

2014-01-01

Isogenic cells sensing identical external signals can take markedly different decisions. Such decisions often correlate with pre-existing cell-to-cell differences in protein levels. When not neglected in signal transduction models, these differences are accounted for in a static manner, by assuming randomly distributed initial protein levels. However, this approach ignores the a priori non-trivial interplay between signal transduction and the source of this cell-to-cell variability: temporal fluctuations of protein levels in individual cells, driven by noisy synthesis and degradation. Thus, modeling protein fluctuations, rather than their consequences on the initial population heterogeneity, would set the quantitative analysis of signal transduction on firmer grounds. Adopting this dynamical view on cell-to-cell differences amounts to recast extrinsic variability into intrinsic noise. Here, we propose a generic approach to merge, in a systematic and principled manner, signal transduction models with stochastic protein turnover models. When applied to an established kinetic model of TRAIL-induced apoptosis, our approach markedly increased model prediction capabilities. One obtains a mechanistic explanation of yet-unexplained observations on fractional killing and non-trivial robust predictions of the temporal evolution of cell resistance to TRAIL in HeLa cells. Our results provide an alternative explanation to survival via induction of survival pathways since no TRAIL-induced regulations are needed and suggest that short-lived anti-apoptotic protein Mcl1 exhibit large and rare fluctuations. More generally, our results highlight the importance of accounting for stochastic protein turnover to quantitatively understand signal transduction over extended durations, and imply that fluctuations of short-lived proteins deserve particular attention. PMID:25340343

Serine/threonine protein phosphatase 6 modulates the radiation sensitivity of glioblastoma

PubMed Central

Shen, Y; Wang, Y; Sheng, K; Fei, X; Guo, Q; Larner, J; Kong, X; Qiu, Y; Mi, J

2011-01-01

Increasing the sensitivity of glioblastoma cells to radiation is a promising approach to improve survival in patients with glioblastoma multiforme (GBM). This study aims to determine if serine/threonine phosphatase (protein phosphatase 6 (PP6)) is a molecular target for GBM radiosensitization treatment. The GBM orthotopic xenograft mice model was used in this study. Our data demonstrated that the protein level of PP6 catalytic subunit (PP6c) was upregulated in the GBM tissue from about 50% patients compared with the surrounding tissue or control tissue. Both the in vitro survival fraction of GBM cells and the patient survival time were highly correlated or inversely correlated with PP6c expression (R2=0.755 and −0.707, respectively). We also found that siRNA knockdown of PP6c reduced DNA-dependent protein kinase (DNA-PK) activity in three different GBM cell lines, increasing their sensitivity to radiation. In the orthotopic mice model, the overexpression of PP6c in GBM U87 cells attenuated the effect of radiation treatment, and reduced the survival time of mice compared with the control mice, while the PP6c knocking-down improved the effect of radiation treatment, and increased the survival time of mice. These findings demonstrate that PP6 regulates the sensitivity of GBM cells to radiation, and suggest small molecules disrupting or inhibiting PP6 association with DNA-PK is a potential radiosensitizer for GBM. PMID:22158480

Chemoradiotherapy for stage III non-small cell lung cancer: have we reached the limit?

PubMed

Xu, Peng; Le Pechoux, Cecile

2015-12-01

Lung cancer is the leading cause of cancer-related mortality in men and the second leading cause in women. Approximately 85% of lung cancer patients have non-small cell lung cancer (NSCLC), and most present with advanced stage at diagnosis. The current treatment for such patients is chemoradiation (CRT) provided concurrently preferably or sequentially with chemotherapy, using conventionally fractionated radiation doses in the range of 60 to 66 Gy in 30 to 33 fractions. An individual patient data based metaanalysis has shown that in good performance status (PS), concomitant CRT was associated to improved survival by 4.5% compared to sequential combination (5-year survival rate of 15.1% and 10.6% respectively). In the recent years, improvement of modern technique of radiotherapy (RT) and new chemotherapy drugs may be favorable for the patients. Furthermore, the positron emission tomography-computed tomography (PET-CT) contributes to improved delineation of RT especially in terms of nodal involvement. Improving outcomes for patients with stage III disease remains a challenge, this review will address the questions that are considered fundamental to improving outcome in patients with stage III NSCLC.

Fermented nondigestible fraction from common bean (Phaseolus vulgaris L.) cultivar Negro 8025 modulates HT-29 cell behavior.

PubMed

Cruz-Bravo, R K; Guevara-Gonzalez, R; Ramos-Gomez, M; Garcia-Gasca, T; Campos-Vega, R; Oomah, B D; Loarca-Piña, G

2011-03-01

The aim of the study was to evaluate the effect of a fermented nondigestible fraction (FNDF) of cooked bean (Phaseolus vulgaris L.) cultivar Negro 8025 on human colon adenocarcinoma HT-29 cell survival. Negro 8025 was chosen for in vitro fermentation based on comparison of chemical composition with 2 other cultivars: Azufrado Higuera and Pinto Durango. Negro 8025 had 58% total dietary fiber, 27% resistant starch, and 20 mg of (+)-catechin equivalents per gram of sample. Short-chain fatty acids (SCFAs) production and pH of the medium were measured after fermentation as indicators of colon protection through induced arrest on cell culture and apoptosis. Butyrate and pH of FNDF of Negro 8025 were higher than the control fermented raffinose extract. The FNDF inhibited HT-29 cell survival in a time- and concentration-dependent manner. The lethal concentration 50 (LC(50)) was 13.63% FNDF (equivalent to 7.36, 0.33, and 3.31 mmol of acetic, propionic, and butyric acids, respectively). DNA fragmentation, an apoptosis indicator, was detected by the TdT-mediated dUTP nick end labeling method in cells treated with the LC(50)-FNDF and a synthetic mixture of SCFAs mimicking LC(50)-FNDF. Our results suggest that common bean is a reliable source of fermentable substrates in colon, producing compounds with potential chemoprotective effect on HT-29 colon adenocarcinoma cells, so it may present an effective alternative to mitigate colon cancer development.

Homologous recombination contributes to the repair of DNA double-strand breaks induced by high-energy iron ions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zafar, Faria; Seidler, Sara B.; Kronenberg, Amy

2010-06-29

To test the contribution of homologous recombinational repair (HRR) in repairing DNA damaged sites induced by high-energy iron ions, we used: (1) HRR-deficient rodent cells carrying a deletion in the RAD51D gene and (2) syngeneic human cells impaired for HRR by RAD51D or RAD51 knockdown using RNA interference. We show that in response to iron ions, HRR contributes to cell survival in rodent cells, and that HRR-deficiency abrogates RAD51 foci formation. Complementation of the HRR defect by human RAD51D rescues both enhanced cytotoxicity and RAD51 foci formation. For human cells irradiated with iron ions, cell survival is decreased, and, inmore » p53 mutant cells, the levels of mutagenesis are increased when HRR is impaired. Human cells synchronized in S phase exhibit more pronounced resistance to iron ions as compared with cells in G1 phase, and this increase in radioresistance is diminished by RAD51 knockdown. These results implicate a role for RAD51-mediated DNA repair (i.e. HRR) in removing a fraction of clustered lesions induced by charged particle irradiation. Our results are the first to directly show the requirement for an intact HRR pathway in human cells in ensuring DNA repair and cell survival in response to high-energy high LET radiation.« less

Dose-per-fraction escalation of accelerated hypofractionated three-dimensional conformal radiotherapy in locally advanced non-small cell lung cancer.

PubMed

Kepka, Lucyna; Tyc-Szczepaniak, Dobromira; Bujko, Krzysztof

2009-07-01

To determine the efficacy of accelerated hypofractionated three-dimensional conformal radiotherapy (3D-CRT) with dose-per-fraction escalation for treatment of stage III non-small cell lung cancer (NSCLC). Between 2001 and 2007, 173 patients with stage III NSCLC were treated using accelerated 3D-CRT and the simultaneous boost technique. Initially, the total dose of 56.7 Gy (including 39.9 Gy to the elective area) was delivered over 4 weeks in fractions of 2.7 Gy (1.9 Gy to the elective area). The dose-per-fraction escalation study commenced after the outcomes of 70 patients had been evaluated. The dose per fraction was increased from 2.7 through 2.8 Gy (level 1 escalation) to 2.9 Gy (level 2 escalation); the total dose increased, respectively, from 56.7 Gy through 58.8 Gy to 60.9 Gy. The dose to the elective area and the overall treatment time remained unchanged. Fit patients received two to three courses of chemotherapy before radiotherapy. The 2- and 3-year overall survival rates were 32 and 19%, respectively (median survival = 17 months). Of the patients, 7% had grade III acute esophageal toxicity and 6% had grade III or greater late pulmonary toxicity. Two of the nine patients who received the level 2 escalation (60.9 Gy) died of pulmonary toxicity. The study was terminated at a dose of 58.8 Gy and this schema was adopted as the institutional policy for treatment of stage III NSCLC. Although dose escalation with accelerated hypofractionated 3D-CRT was limited, the results and toxicity profiles obtained using this technique are promising.

Characterization of Photofrin photobleaching for singlet oxygen dose estimation during photodynamic therapy of MLL cells in vitro

NASA Astrophysics Data System (ADS)

Dysart, Jonathan S.; Patterson, Michael S.

2005-06-01

A singlet oxygen dose model is developed for PDT with Photofrin. The model is based on photosensitizer photobleaching kinetics, and incorporates both singlet oxygen and non-singlet oxygen mediated bleaching mechanisms. To test our model, in vitro experiments were performed in which MatLyLu (MLL) cells were incubated in Photofrin and then irradiated with 532 nm light. Photofrin fluorescence was monitored during treatment and, at selected fluence levels, cell viability was determined using a colony formation assay. Cell survival correlated well to calculated singlet oxygen dose, independent of initial Photofrin concentration or oxygenation. About 2 × 108 molecules of singlet oxygen per cell were required to reduce the surviving fraction by 1/e. Analysis of the photobleaching kinetics suggests that the lifetime of singlet oxygen in cells is 0.048 ± 0.005 µs. The generation of fluorescent photoproducts was not a result of singlet oxygen reactions exclusively, and therefore did not yield additional information to aid in quantifying singlet oxygen dose.

Transcriptome-derived stromal and immune scores infer clinical outcomes of patients with cancer.

PubMed

Liu, Wei; Ye, Hua; Liu, Ying-Fu; Xu, Chao-Qun; Zhong, Yue-Xian; Tian, Tian; Ma, Shi-Wei; Tao, Huan; Li, Ling; Xue, Li-Chun; He, Hua-Qin

2018-04-01

The stromal and immune cells that form the tumor microenvironment serve a key role in the aggressiveness of tumors. Current tumor-centric interpretations of cancer transcriptome data ignore the roles of stromal and immune cells. The aim of the present study was to investigate the clinical utility of stromal and immune cells in tissue-based transcriptome data. The 'Estimation of STromal and Immune cells in MAlignant Tumor tissues using Expression data' (ESTIMATE) algorithm was used to probe diverse cancer datasets and the fraction of stromal and immune cells in tumor tissues was scored. The association between the ESTIMATE scores and patient survival data was asessed; it was indicated that the two scores have implications for patient survival, metastasis and recurrence. Analysis of a colorectal cancer progression dataset revealed that decreased levels immune cells could serve an important role in cancer progression. The results of the present study indicated that trasncriptome-derived stromal and immune scores may be a useful indicator of cancer prognosis.

Sensitivity of cultured skin fibroblasts from patients with neurofibromatosis to DNA-damaging agents

DOE Office of Scientific and Technical Information (OSTI.GOV)

Woods, W.G.; McKenzie, B.; Letourneau, M.A.

Neurofibromatosis (NF) is an autosomal dominant disorder associated with various constitutional abnormalities as well as a striking predisposition for malignant and nonmalignant neoplasms, both in cells originating in and not originating in the neural crest. We have examined the sensitivity of cultured skin fibroblasts from patients with neurofibromatosis to several types of DNA damage. Fibroblasts in Dulbecco's modified Eagle's medium were plated at 10(2) to 2 X 10(4) cells per 75 cm2 tissue culture plates, and exposed to various doses of gamma radiation (leads to DNA scission), actinomycin D, or mitomycin C. Cells were reincubated for 15 to 40 daysmore » until surviving colonies exhibited greater than 30-50 cells. Plates were then stained with 1% methylene blue and the colonies counted, with surviving fraction determined relative to plating efficiency. Nine skin fibroblast cell strains from normal individuals were studied as controls. One neurofibromatosis (NF) cell strain, SB23, exhibited normal sensitivity to all three DNA-damaging agents studied in early (7-8) and middle (12-13) in vitro passage. Strain GM0622, on the other hand, exhibited normal sensitivity to the three DNA-damaging agents studied at early passage, but showed a significant decrease in survival after exposure to both gamma radiation (D0 = 106 rad) and actinomycin D (D0 = 0.024 mcg/ml) with increasing passage. Strain GM1639 exhibited decreased survival after actinomycin D exposure at early passage (D0 = 0.017 mcg/ml), with normal survival after exposure to gamma radiation and mitomycin C at the same passage.« less

Stem cells in cardiac repair.

PubMed

Henning, Robert J

2011-01-01

Myocardial infarction is the leading cause of death among people in industrialized nations. Although the heart has some ability to regenerate after infarction, myocardial restoration is inadequate. Consequently, investigators are currently exploring the use of human embryonic stem cells (hESCs), skeletal myoblasts and adult bone marrow stem cells to limit infarct size. hESCs are pluripotent cells that can regenerate myocardium in infarcted hearts, attenuate heart remodeling and contribute to left ventricle (LV) systolic force development. Since hESCs can form heart teratomas, investigators are differentiating hESCs toward cardiac progenitor cells prior to transplantation into hearts. Large quantities of hESCs cardiac progenitor cells, however, must be generated, immune rejection must be prevented and grafts must survive over the long term to significantly improve myocardial performance. Transplanted autologous skeletal myoblasts can survive in infarcted myocardium in small numbers, proliferate, differentiate into skeletal myofibers and increase the LV ejection fraction. These cells, however, do not form electromechanical connections with host cardiomyocytes. Consequently, electrical re-entry can occur and cause cardiac arrhythmias. Autologous bone marrow mononuclear cells contain hematopoietic and mesenchymal stem cells. In several meta-analyses, patients with coronary disease who received autologous bone marrow cells by intracoronary injection show significant 3.7% (range: 1.9-5.4%) increases in LV ejection fraction, decreases in LV end-systolic volume of -4.8 ml (range: -1.4 to -8.2 ml) and reductions in infarct size of 5.5% (-1.9 to -9.1%), without experiencing arrhythmias. Bone marrow cells appear to release biologically active factors that limit myocardial damage. Unfortunately, bone marrow cells from patients with chronic diseases propagate poorly and can die prematurely. Substantial challenges must be addressed and resolved to advance the use of stem cells in cardiac repair including identifying the optimal stem cell(s) that permit transplantation without requirements for host immune suppression; timing of stem cell transplantation that maximizes chemoattraction of stem cells to infarcts; and determining the optimal technique for injecting stem cells for cardiac repair. Techniques must be developed to enhance survival and propagation of stem cells in the myocardium. These studies will require close cooperation and interaction of scientists and clinicians. Cell-based cardiac repair in the 21st century will offer new hope for millions of patients worldwide with myocardial infarctions who, otherwise, would suffer from the relentless progression of heart disease to heart failure and death.

Interleukin-1 modulatory effect on the action of chemotherapeutic drugs and localized irradiation of the lip, duodenum, and tumor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zaghloul, M.S.; Dorie, M.J.; Kallman, R.F.

1993-06-15

This study was conducted to examine the radioprotective and radiochemoprotective capabilities of interleukin 1[beta] (IL-1) on two acute-reacting normal tissues of the C3H mouse, the mucosa of the lip and the duodenum. Also assessed was the modulating effect of IL-1 on tumor growth in the same strain of mice. IL-1 was administered to C3H-Km mice in combination with fractionated irradiation, or with cyclophosphamide, cisplatin, or 5-fluorouracil (5FU) followed by irradiation. Normal tissue damage was evaluated in the mouse lip, using a subjective scoring system for tissue reaction, and in the duodenum, using the crypt cell survival assay. RIF-1 fibrosarcoma tumormore » response was assayed with the regrowth delay method. IL-1 protected against the acute reaction produced by fractionated irradiation in the lip mucosa, shifting the dose-response curve by 3.8 Gy. IL-1 was protective when injected intraperitoneally 24 hr before CY or c-DDP, which were given immediately before the first of five daily radiation dose fractions. The dose-response curves for cyclophosphamide and cisplatin were shifted 4.0 Gy and 1.6 Gy, respectively. IL-1 did not protect against 5FU toxicity when treatments were administered in that same sequence; however, when 5FU was given 4 or 8 hr before IL-1 and the first radiation dose fraction followed 20 or 16 hr later, there was significant protection and the curves were separated by 1.5 Gy or 3.5 Gy. IL-1 also protected duodenal crypt cells against the cytocidal effect of fractionated irradiation, with a dose difference of 1.5 Gy and an improvement of crypt survival of 11.7%. It was even more immediately before the first of five daily radiation doses, with the dose differences of 4.4 and 5.3 Gy, respectively, and improvements of crypt survival of 33.8 and 29.9%, respectively. There was no modification by IL-1 of the effect of irradiation alone on the RIF-1 tumor. 45 refs., 8 figs., 1 tab.« less

Optimization of the temporal pattern of radiation: An IMRT based study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Altman, Michael B.; Chmura, Steven J.; Deasy, Joseph O.

Purpose: To investigate how the temporal pattern of dose applied during a single-intensity modulated radiation therapy (IMRT) fraction can be arranged to maximize or minimize cell kill. Methods and Materials: Using the linear-quadratic repair-time model and a simplified IMRT delivery pattern model, the surviving fraction of cells for a single fraction was calculated for all permutations of the dose delivery pattern for an array of clinically based IMRT cases. Maximization of cell kill was achieved by concentrating the highest doses in the middle of a fraction, while minimization was achieved by spreading the highest doses between the beginning and end.more » The percent difference between maximum and minimum cell kill (%Diff{sub min/max}) and the difference between maximum and minimum total doses normalized to 2 Gy/fx ({delta}NTD{sub 2Gy}) was calculated for varying fraction durations (T), {alpha}/{beta} ratios, and doses/fx. Results: %Diff{sub min/max} and {delta}NTD{sub 2Gy} both increased with increasing T and with decreasing {alpha}/{beta}. The largest increases occurred with dose/fx. With {alpha}/{beta} = 3 Gy and 30 min/fx, %Diff{sub min/max} ranged from 2.7-5.3% for 2 Gy/fx to 48.6-74.1% for 10 Gy/fx, whereas {delta}NTD{sub 2Gy} ranged from 1.2 Gy-2.4 Gy for 30 fractions of 2 Gy/fx to 2.3-4.8 Gy for 2 fractions of 10.84 Gy/fx. Using {alpha}/{beta} = 1.5 Gy, an analysis of prostate hypofractionation schemes yielded differences in clinical outcome based on the pattern of applied dose ranging from 3.2%-6.1% of the treated population. Conclusions: Rearrangement of the temporal pattern of dose for a single IMRT fraction could be used to optimize cell kill and to directly, though modestly, affect treatment outcome.« less

Therapeutic benefits in grid irradiation on Tomotherapy for bulky, radiation-resistant tumors.

PubMed

Narayanasamy, Ganesh; Zhang, Xin; Meigooni, Ali; Paudel, Nava; Morrill, Steven; Maraboyina, Sanjay; Peacock, Loverd; Penagaricano, Jose

2017-08-01

Spatially fractionated radiation therapy (SFRT or grid therapy) has proven to be effective in management of bulky tumors. The aim of this project is to study the therapeutic ratio (TR) of helical Tomotherapy (HT)-based grid therapy using linear-quadratic cell survival model. HT-based grid (or HT-GRID) plan was generated using a patient-specific virtual grid pattern of high-dose cylindrical regions using MLCs. TR was defined as the ratio of normal tissue surviving fraction (SF) under HT-GRID irradiation to an open debulking field of an equivalent dose that result in the same tumor cell SF. TR was estimated from DVH data on ten HT-GRID patient plans with deep seated, bulky tumor. Dependence of the TR values on radiosensitivity of the tumor cells and prescription dose was analyzed. The mean ± standard deviation (SD) of TR was 4.0 ± 0.7 (range: 3.1-5.5) for the 10 patients with single fraction maximum dose of 20 Gy to GTV assuming a tumor cell SF at 2 Gy (SF2 t ) value of 0·5. In addition, the mean ± SD of TR values for SF2 t values of 0.3 and 0.7 were found to be 1 ± 0.1 and 18.0 ± 5.1, respectively. Reducing the prescription dose to 15 and 10 Gy lowered the respective TR values to 2.0 ± 0.2 and 1.2 ± 0.04 for a SF2 t value of 0.5. HT-GRID therapy demonstrates a significant therapeutic advantage over uniform dose from an open field irradiation for the same tumor cell kill. TR increases with the radioresistance of the tumor cells and with prescription dose.

Population-based survival-cure analysis of ER-negative breast cancer.

PubMed

Huang, Lan; Johnson, Karen A; Mariotto, Angela B; Dignam, James J; Feuer, Eric J

2010-08-01

This study investigated the trends over time in age and stage specific population-based survival of estrogen receptor negative (ER-) breast cancer patients by examining the fraction of cured patients and the median survival time for uncured patients. Cause-specific survival data from the Surveillance, Epidemiology, and End Results program for cases diagnosed during 1992-1998 were used in mixed survival cure models to evaluate the cure fraction and the extension in survival for uncured patients. Survival trends were compared with adjuvant chemotherapy data available from an overlapping patterns-of-care study. For stage II N+ disease, the largest increase in cure fraction was 44-60% (P = 0.0257) for women aged >or=70 in contrast to a 7-8% point increase for women aged <50 or 50-69 (P = 0.056 and 0.038, respectively). For women with stage III disease, the increases in the cure fraction were not statistically significant, although women aged 50-69 had a 10% point increase (P = 0.103). Increases in cure fraction correspond with increases in the use of adjuvant chemotherapy, particularly for the oldest age group. In this article, for the first time, we estimate the cure fraction for ER- patients. We notice that at age >o5r=70, the accelerated increase in cure fraction from 1992 to 1998 for women with stage II N+ compared with stage III suggests a selective benefit for chemotherapy in the lower stage group.

Chemical characterization and cytotoxic, genotoxic, and mutagenic properties of Baccharis trinervis (Lam, Persoon) from Colombia and Brazil.

PubMed

Jaramillo-García, Victoria; Trindade, Cristiano; Lima, Elisiane; Guecheva, Temenouga N; Villela, Izabel; Martinez-Lopez, Wilner; Corrêa, Dione S; Ferraz, Alexandre de B F; Moura, Sidnei; Sosa, Milton Quintana; Da Silva, Juliana; Henriques, João Antônio Pegas

2018-03-01

Baccharis trinervis (Lam, Persoon) leaves are used in the traditional medicine for the treatment of high fevers, edema, inflammation, sores and muscle cramps, snakebites and as antiseptic. To investigate the cytotoxic, genotoxic, and mutagenic effects of extracts and fractions of B. trinervis from Brazil and Colombia in Chinese Hamster Ovary (CHO) cells, and to examine the mutagenic activity in Salmonella typhimurium. Aqueous extracts (AE) of aerial parts of B. trinervis from Brazil (B) and Colombia (C) were fractioned in ethyl acetate fraction (EAF), butanol extract (BF), and aqueous residue fraction (ARF). Qualitative chemical screening and determination of total flavonoid content were made. Identification of chemical constituents was performed by High Performance Liquid Chromatography (HPLC) and High Resolution Mass Spectrometry (HRMS). For the in vitro tests, CHO cells were treated for 3h with extracts and fractions. The cytotoxic activity was evaluated by clonal survival and 3-(4.5-dimethylthiazole-2-yl)-2.5-biphenyl tetrazolium bromide reduction assay (MTT). Genotoxic and mutagenic effects were evaluated by the alkaline comet assay and Cytokinesis-blockage micronucleus test (CBMN), respectively. Additionally, Salmonella/microsome assay was carried out to determinate the mutagenic effects in EAF from Brazil and Colombia. Phytochemical analyses indicated the presence of saponins and flavonoids. AE and EAF were the samples with the highest quantity of total flavonoids. HPLC showed the presence of luteolin only in AEC, and caffeic acid, ellagic acid, rosmarinic acid, and rutin were identified in AEB and AEC (AEC>AEB). The HRMS in positive mode of EAFB and EAFC showed presence of two carboxylic acids, coumarin, and two terpenoids. In addition, were identified one terpenoid and two carboxylic acids in AE, BF and ARF of B. trinervis from both countries in negative mode. Dose-dependent cytotoxic effects were observed in CHO cells treated with B. trinervis extracts and fractions by using clonal survival and MTT at concentrations higher than 0.05mg/mL. All the extracts and fractions induced DNA strand breaks in CHO cells with dose-dependent response, mostly EAFB and EAFC. The EAF from Brazil and Colombia showed mutagenic effect at 0.5mg/mL, while the other fractions did not show a significant difference in relation to the control. No mutagenic effects were found in EAF from both countries by the Salmonella/microsome assay. Cytotoxic and genotoxic effects were demonstrated in all extracts and fractions used, although only EAF showed mutagenic effects by CBMN, but not by Salmonella/microsome assay. Our results suggest that flavonoids, phenylpropanoids, coumarins, and diterpenes may be responsible for the cytotoxic, genotoxic and mutagenic effects observed. Copyright © 2017 Elsevier B.V. All rights reserved.

Genotoxic and mutagenic properties of Bauhinia platypetala extract, a traditional Brazilian medicinal plant.

PubMed

Santos, Francisco José Borges Dos; Moura, Dinara Jaqueline; Péres, Valéria Flores; Sperotto, Angelo Regis de Moura; Caramão, Elina Bastos; Cavalcante, Ana Amélia de Carvalho Melo; Saffi, Jenifer

2012-12-18

Bauhinia platypetala Burch. is a traditionally used Brazilian medicinal plant, although no evidence in the literature substantiates the safety of its use. The aim of this study was to investigate the safety of the ethanolic extract and the ethereal fraction of B. platypetala leaves. The identification of chemical compounds from the B. platypetala ethanolic extract and its ethereal fraction was performed by GC/MS and ESI-MS/MS. The plant's toxicological, cytotoxic, mutagenic and genotoxic properties were determined in Saccharomyces cerevisiae strains and V79 cell culture by survival assays and comet assay. The major compound identified in the B. platypetala ethanolic extract is palmitic acid, kaempferitirin and quercitrin, while the B. platypetala ethereal fraction was found to be rich in phytol, gamma-sitosterol and vitamin E. Moreover, the results indicated that the B. platypetala ethanolic extract has an anti-oxidative effect against H(2)O(2) in yeast. In addition, the B. platypetala ethanolic extract did not induce mutagenic effects on the S. cerevisiae N123 strain, but the ethereal fraction of B. platypetala at higher concentrations (250-500 μg/mL) induced cytotoxicity and mutagenicity. A slight cytotoxic effect was observed in mammalian V79 cells; however, both the B. platypetala ethanolic extract and its ethereal fraction were able to induce DNA strand breaks in V79 cells, as detected by the alkaline comet assay. The B. platypetala ethanolic extract has antioxidant action and showed absence of mutagenic effects in yeast S. cerevisiae. On the other hand B. platypetala ethereal fraction is mutagenic and does not show antioxidant activity in yeast. In mammalian cells B. platypetala ethanolic extract and it's ethereal fraction induce cyotoxic and genotoxic action. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Persistent DNA Damage in Spermatogonial Stem Cells After Fractionated Low-Dose Irradiation of Testicular Tissue

DOE Office of Scientific and Technical Information (OSTI.GOV)

Grewenig, Angelika; Schuler, Nadine; Rübe, Claudia E., E-mail: claudia.ruebe@uks.eu

Purpose: Testicular spermatogenesis is extremely sensitive to radiation-induced damage, and even low scattered doses to testis from radiation therapy may pose reproductive risks with potential treatment-related infertility. Radiation-induced DNA double-strand breaks (DSBs) represent the greatest threat to the genomic integrity of spermatogonial stem cells (SSCs), which are essential to maintain spermatogenesis and prevent reproduction failure. Methods and Materials: During daily low-dose radiation with 100 mGy or 10 mGy, radiation-induced DSBs were monitored in mouse testis by quantifying 53 binding protein 1 (53BP-1) foci in SSCs within their stem cell niche. The accumulation of DSBs was correlated with proliferation, differentiation, and apoptosis ofmore » testicular germ cell populations. Results: Even very low doses of ionizing radiation arrested spermatogenesis, primarily by inducing apoptosis in spermatogonia. Eventual recovery of spermatogenesis depended on the survival of SSCs and their functional ability to proliferate and differentiate to provide adequate numbers of differentiating spermatogonia. Importantly, apoptosis-resistant SSCs resulted in increased 53BP-1 foci levels during, and even several months after, fractionated low-dose radiation, suggesting that surviving SSCs have accumulated an increased load of DNA damage. Conclusions: SSCs revealed elevated levels of DSBs for weeks after radiation, and if these DSBs persist through differentiation to spermatozoa, this may have severe consequences for the genomic integrity of the fertilizing sperm.« less

Prognostic significance of S-phase fractions in peritumoral invading zone analyzed by laser scanning cytometry in patients with high-grade glioma: A preliminary study.

PubMed

Nakajima, Syoichi; Morii, Ken; Takahashi, Hitoshi; Fujii, Yukihiko; Yamanaka, Ryuya

2016-03-01

The predominant characteristic of malignant glioma is the presence of invading tumor cells in the peritumoral zone. Distinguishing between tumor cells and normal cells in a peritumoral lesion is challenging. Therefore, the aim of the present study was to investigate the cell-cycle phase measurements of fixed paraffin-embedded specimens from the peritumoral invading zone of high-grade gliomas using laser scanning cytometry. A total of 12 high-grade gliomas (2 anaplastic astrocytomas and 10 glioblastomas) were studied. The tumor core and peritumoral invading zone of each tumor specimen were investigated. Tissue sections (50 µm) from the paraffin blocks were deparaffinized, rehydrated and enzymatically disintegrated, and the cells in suspension were stained with propidium iodide and placed on microscope slides. A slight trend for an increased S-phase fraction in the peritumoral invading zone compared with the tumor core was observed (P=0.24). Additionally, there was a trend for a decrease in the overall survival time of patients with increasing peritumoral invading zone S-phase fraction (P=0.12). These data suggest that laser scanning cytometry is a powerful and clinically relevant tool for the objective analysis of the cell cycle in malignant gliomas.

Angels and demons: Th17 cells represent a beneficial response, while neutrophil IL-17 is associated with poor prognosis in squamous cervical cancer.

PubMed

Punt, Simone; Fleuren, Gert Jan; Kritikou, Eva; Lubberts, Erik; Trimbos, J Baptist; Jordanova, Ekaterina S; Gorter, Arko

2015-01-01

The role of interleukin (IL)-17 in cancer remains controversial. In view of the growing interest in the targeting of IL-17, knowing its cellular sources and clinical implications is crucial. In the present study, we unraveled the phenotype of IL-17 expressing cells in cervical cancer using immunohistochemical double and immunofluorescent triple stainings. In the tumor stroma, IL-17 was found to be predominantly expressed by neutrophils (66%), mast cells (23%), and innate lymphoid cells (8%). Remarkably, T-helper 17 (Th17) cells were a minor IL-17 expressing population (4%). A similar distribution was observed in the tumor epithelium. The Th17 and granulocyte fractions were confirmed in head and neck, ovarian, endometrial, prostate, breast, lung, and colon carcinoma. An above median number of total IL-17 expressing cells was an independent prognostic factor for poor disease-specific survival in early stage disease ( p = 0.016). While a high number of neutrophils showed at trend toward poor survival, the lowest quartile of mast cells correlated with poor survival ( p = 0.011). IL-17 expressing cells and neutrophils were also correlated with the absence of vaso-invasion ( p < 0.01). IL-17 was found to increase cell growth or tightness of cervical cancer cell lines, which may be a mechanism for tumorigenesis in early stage disease. These data suggest that IL-17, primarily expressed by neutrophils, predominantly promotes tumor growth, correlated with poor prognosis in early stage disease. Strikingly, a high number of Th17 cells was an independent prognostic factor for improved survival ( p = 0.026), suggesting Th17 cells are part of a tumor suppressing immune response.

Angels and demons: Th17 cells represent a beneficial response, while neutrophil IL-17 is associated with poor prognosis in squamous cervical cancer

PubMed Central

Punt, Simone; Fleuren, Gert Jan; Kritikou, Eva; Lubberts, Erik; Trimbos, J. Baptist; Jordanova, Ekaterina S.; Gorter, Arko

2015-01-01

The role of interleukin (IL)-17 in cancer remains controversial. In view of the growing interest in the targeting of IL-17, knowing its cellular sources and clinical implications is crucial. In the present study, we unraveled the phenotype of IL-17 expressing cells in cervical cancer using immunohistochemical double and immunofluorescent triple stainings. In the tumor stroma, IL-17 was found to be predominantly expressed by neutrophils (66%), mast cells (23%), and innate lymphoid cells (8%). Remarkably, T-helper 17 (Th17) cells were a minor IL-17 expressing population (4%). A similar distribution was observed in the tumor epithelium. The Th17 and granulocyte fractions were confirmed in head and neck, ovarian, endometrial, prostate, breast, lung, and colon carcinoma. An above median number of total IL-17 expressing cells was an independent prognostic factor for poor disease-specific survival in early stage disease (p = 0.016). While a high number of neutrophils showed at trend toward poor survival, the lowest quartile of mast cells correlated with poor survival (p = 0.011). IL-17 expressing cells and neutrophils were also correlated with the absence of vaso-invasion (p < 0.01). IL-17 was found to increase cell growth or tightness of cervical cancer cell lines, which may be a mechanism for tumorigenesis in early stage disease. These data suggest that IL-17, primarily expressed by neutrophils, predominantly promotes tumor growth, correlated with poor prognosis in early stage disease. Strikingly, a high number of Th17 cells was an independent prognostic factor for improved survival (p = 0.026), suggesting Th17 cells are part of a tumor suppressing immune response. PMID:25949866

Malignant glioma--a nemesis which requires clinical and basic investigation in radiation oncology

DOE Office of Scientific and Technical Information (OSTI.GOV)

Davis, L.W.

1989-06-01

Malignant gliomas account for 40% of all central nervous system malignancies. These are essentially localized neoplastic tumors that have defied most treatment. In spite of improved techniques, surgery is unlikely to increase survival further since true cancer operations cannot be performed. Radiation therapy has made a significant difference in outcome. Investigation in radiation oncology is essential for further improvement in the treatment of these tumors. The pattern of failure is local tumor recurrence, but the method to overcome this resistance to treatment is not clear. Radiation therapy techniques and inherent radio-resistance have been considered as possible reasons for failure. Withmore » newer imaging procedures, the extent of tumor can be more accurately defined allowing improved treatment planning. Identifying an effective treatment program is more difficult. Studies have documented the beneficial effect of radiation therapy, but the optimal dose or fractionation schedule has not been determined. Whereas some studies have reported improved survival using higher radiation doses, others have reported no benefit. More recently, studies of multiple daily fractionation schedules have been conducted using two or three daily fractions. Equally confusing results have been reported. Histologically, these tumors have necrotic areas and may be radioresistant due to hypoxic cells. Treatment methods designed to overcome the radioprotective effect of hypoxia have yielded disappointing results. The addition of hypoxic cell sensitizers has not produced the expected improvement in outcome. Studies using neutron radiation therapy report tumor control but not improved survival. Radiobiologic information is now available which may contribute to our understanding of the response of these tumors to radiation. Further laboratory and clinical investigation is required. 83 references.« less

Extensive disease small cell carcinoma of the lung; trial of non-cross resistant chemotherapy and consolidation radiotherapy. [X ray

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dillman, R.O., Taelle, R., Segren, S.; Royston, I.; Koziol, J.

1982-05-15

Twenty-nine patients with extensive disease, small-cell carcinoma of the lung, were treated with two cycles of intensive combination chemotherapy: HexaVAC (hexamethylmelamine, vincristine, Adriamycin, cyclophosphamide). Responders received prophylactic cranial radiation (2000 rad/10 fractions) and non cross resistant chemotherapy via a schedule of alternating cycles of CMV (cyclophosphamide, methotrexate, VP-16-213) and AMV (Adriamycin, methotrexate, VP-16-213). Whenever a complete response was achieved, consolidation radiotherapy was given to the lung primary (4000 rad/20 fractions, split dose) and abdominal metastases (2000 rad/10 fractions) synchronous with CMV therapy. The complete response rate was 14% with HexaVAC, but increased to 38% during CMV/AMV. Total response rate (completemore » and partial) was 59% and median survival was 42 weeks. Prophylactic brain radiation prevented clinical relapse in the brain in all 14 patients who received it. However, consolidation radiotherapy failed to prevent clinical relapse in the lung and/or liver, and therapeutic brain radiation (3000 rad) failed to prevent relapse in that site. The simultaneous administration of radiotherapy and chemotherapy was well-tolerated although two patients with poor performance status died of infectious complications while leukopenic. In spite of the high response rate, durable remissions with prolonged disease free survival were rare. Further evaluation of induction, consolidation, and maintenance modes of therapy are indicated.« less

Survival times for canine intranasal sarcomas treated with radiation therapy: 86 cases (1996-2011).

PubMed

Sones, Evan; Smith, Annette; Schleis, Stephanie; Brawner, William; Almond, Gregory; Taylor, Kathryn; Haney, Siobhan; Wypij, Jackie; Keyerleber, Michele; Arthur, Jennifer; Hamilton, Terrance; Lawrence, Jessica; Gieger, Tracy; Sellon, Rance; Wright, Zack

2013-01-01

Sarcomas comprise approximately one-third of canine intranasal tumors, however few veterinary studies have described survival times of dogs with histologic subtypes of sarcomas separately from other intranasal tumors. One objective of this study was to describe median survival times for dogs treated with radiation therapy for intranasal sarcomas. A second objective was to compare survival times for dogs treated with three radiation therapy protocols: daily-fractionated radiation therapy; Monday, Wednesday, and Friday fractionated radiation therapy; and palliative radiation therapy. Medical records were retrospectively reviewed for dogs that had been treated with radiation therapy for confirmed intranasal sarcoma. A total of 86 dogs met inclusion criteria. Overall median survival time for included dogs was 444 days. Median survival time for dogs with chondrosarcoma (n = 42) was 463 days, fibrosarcoma (n = 12) 379 days, osteosarcoma (n = 6) 624 days, and undifferentiated sarcoma (n = 22) 344 days. Dogs treated with daily-fractionated radiation therapy protocols; Monday, Wednesday and Friday fractionated radiation therapy protocols; and palliative radiation therapy protocols had median survival times of 641, 347, and 305 days, respectively. A significant difference in survival time was found for dogs receiving curative intent radiation therapy vs. palliative radiation therapy (P = 0.032). A significant difference in survival time was also found for dogs receiving daily-fractionated radiation therapy vs. Monday, Wednesday and Friday fractionated radiation therapy (P = 0.0134). Findings from this study support the use of curative intent radiation therapy for dogs with intranasal sarcoma. Future prospective, randomized trials are needed for confirmation of treatment benefits. © 2012 Veterinary Radiology & Ultrasound.

Interactions of a lignin-rich fraction from brewer's spent grain with gut microbiota in vitro.

PubMed

Niemi, Piritta; Aura, Anna-Marja; Maukonen, Johanna; Smeds, Annika I; Mattila, Ismo; Niemelä, Klaus; Tamminen, Tarja; Faulds, Craig B; Buchert, Johanna; Poutanen, Kaisa

2013-07-10

Lignin is a constituent of plant cell walls and thus is classified as part of dietary fiber. However, little is known about the role of lignin in gastrointestinal fermentation. In this work, a lignin-rich fraction was prepared from brewer's spent grain and subjected to an in vitro colon model to study its potential bioconversions and interactions with fecal microbiota. No suppression of microbial conversion by the fraction was observed in the colon model, as measured as short-chain fatty acid production. Furthermore, no inhibition on the growth was observed when the fraction was incubated with strains of lactobacilli and bifidobacteria. In fact, the lignin-rich fraction enabled bifidobacteria to survive longer than with glucose. Several transiently appearing phenolic compounds, very likely originating from lignin, were observed during the fermentation. This would indicate that the gut microbiota was able to partially degrade lignin and metabolize the released compounds.

Intracellular survival of Staphylococcus aureus during persistent infection in the insect Tenebrio molitor.

PubMed

McGonigle, John E; Purves, Joanne; Rolff, Jens

2016-06-01

Survival of bacteria within host cells and tissues presents a challenge to the immune systems of higher organisms. Escape from phagocytic immune cells compounds this issue, as immune cells become potential vehicles for pathogen dissemination. However, the duration of persistence within phagocytes and its contribution to pathogen load has yet to be determined. We investigate the immunological significance of intracellular persistence within the insect model Tenebrio molitor, assessing the extent, duration and location of bacterial recovery during a persistent infection. Relative abundance of Staphylococcus aureus in both intracellular and extracellular fractions was determined over 21 days, and live S. aureus were successfully recovered from both the hemolymph and within phagocytic immune cells across the entire time course. The proportion of bacteria recovered from within phagocytes also increased over time. Our results show that to accurately estimate pathogen load it is vital to account for bacteria persisting within immune cells. Copyright © 2016 Elsevier Ltd. All rights reserved.

Activation of the N-Ras-PI3K-Akt-mTOR Pathway by Hepatitis C Virus: Control of Cell Survival and Viral Replication

PubMed Central

Mannová, Petra; Beretta, Laura

2005-01-01

The hepatitis C virus (HCV) replication complex is localized within detergent-resistant membranes or lipid rafts. We analyzed the protein contents of detergent-resistant fractions isolated from Huh7 cells expressing a self-replicating full-length HCV-1b genome. Using two-dimensional gel electrophoresis followed by mass spectrometry, we identified N-Ras as one of the proteins in which expression was increased in the detergent-resistant fractions from HCV genomic replicon clones compared to control cells. N-Ras is an activator of the phosphatidylinositol-3-kinase (PI3K)-Akt pathway. We found that the activities of PI3K and Akt, as well as the activity of their downstream target, mTOR, in the HCV-replicating cells were increased. Both PI3K-Akt- and mTOR-dependent pathways have been shown to promote cell survival. In agreement with this, HCV replicon cells were resistant to serum starvation-induced apoptosis. We also characterized the role of this pathway in HCV replication. Reduction of N-Ras expression by transfection of N-Ras small interfering RNA (siRNA) resulted in increased replication of HCV. We observed a similar increase in HCV replication in cells treated with the PI3K inhibitor LY294002 and in cells transfected with mTOR siRNA. Taken together, these data suggest that increased N-Ras levels in subcellular sites of HCV replication and stimulation of the prosurvival PI3K-Akt pathway and mTOR by HCV not only protect cells against apoptosis but also contribute to the maintenance of steady-state levels of HCV replication. These effects may contribute to the establishment of persistent infection by HCV. PMID:15994768

HI-CHART: a phase I/II study on the feasibility of high-dose continuous hyperfractionated accelerated radiotherapy in patients with inoperable non-small-cell lung cancer.

PubMed

De Ruysscher, Dirk; Wanders, Rinus; van Haren, Erik; Hochstenbag, Monique; Geraedts, Wiel; Pitz, Cordula; Simons, Jean; Boersma, Liesbeth; Verschueren, Tom; Minken, Andre; Bentzen, Søren M; Lambin, Philippe

2008-05-01

To determine the feasibility of high-dose continuous hyperfractionated accelerated radiotherapy in patients with inoperable non-small-cell lung cancer (NSCLC). In a prospective, Phase I/II study, according to the risk for radiation pneumonitis, three risk groups were defined: V(20) <25%, V(20) 25-37%, and V(20) >37%. The dose was administered in three steps from 61.2 Gy/34 fractions/23 days to 64.8 Gy/36 fractions/24 days to 68.40 Gy/38 fractions/25 days (1.8 Gy b.i.d. with 8-h interval), using a three-dimensional conformal technique. Only the mediastinal lymph node areas that were positive on the pretreatment (18)F-deoxy-D-glucose positron emission tomography scan were included in the target volume. The primary endpoint was toxicity. A total of 48 Stage I-IIIB patients were included. In all risk groups, 68.40 Gy/38 fractions/25 days could be administered. Maximal toxicity according to the risk groups was as follows: V(20) <25% (n = 35): 1 Grade 4 (G4) lung and 1 G3 reversible esophageal toxicity; V(20) 35-37% (n = 12): 1 G5 lung and 1 G3 reversible esophageal toxicity. For the whole group, local tumor recurrence occurred in 25% (95% confidence interval 14%-40%) of the patients, with 1 of 48 (2.1%; upper one-sided 95% confidence limit 9.5%) having an isolated nodal recurrence. The median actuarial overall survival was 20 months, with a 2-year survival rate of 36%. High-dose continuous hyperfractionated accelerated radiotherapy up to a dose of 68.40 Gy/38 fractions/25 days (a biologic equivalent of approximately 80 Gy when delivered in conventional fractionation) in patients with inoperable NSCLC and a V(20) up to 37% is feasible.

Repopulation Kinetics and the Linear-Quadratic Model

NASA Astrophysics Data System (ADS)

O'Rourke, S. F. C.; McAneney, H.; Starrett, C.; O'Sullivan, J. M.

2009-08-01

The standard Linear-Quadratic (LQ) survival model for radiotherapy is used to investigate different schedules of radiation treatment planning for advanced head and neck cancer. We explore how these treament protocols may be affected by different tumour repopulation kinetics between treatments. The laws for tumour cell repopulation include the logistic and Gompertz models and this extends the work of Wheldon et al. [1], which was concerned with the case of exponential repopulation between treatments. Treatment schedules investigated include standarized and accelerated fractionation. Calculations based on the present work show, that even with growth laws scaled to ensure that the repopulation kinetics for advanced head and neck cancer are comparable, considerable variation in the survival fraction to orders of magnitude emerged. Calculations show that application of the Gompertz model results in a significantly poorer prognosis for tumour eradication. Gaps in treatment also highlight the differences in the LQ model with the effect of repopulation kinetics included.

Genomic and Histopathological Tissue Biomarkers That Predict Radiotherapy Response in Localised Prostate Cancer

PubMed Central

Wilkins, Anna; Dearnaley, David; Somaiah, Navita

2015-01-01

Localised prostate cancer, in particular, intermediate risk disease, has varied survival outcomes that cannot be predicted accurately using current clinical risk factors. External beam radiotherapy (EBRT) is one of the standard curative treatment options for localised disease and its efficacy is related to wide ranging aspects of tumour biology. Histopathological techniques including immunohistochemistry and a variety of genomic assays have been used to identify biomarkers of tumour proliferation, cell cycle checkpoints, hypoxia, DNA repair, apoptosis, and androgen synthesis, which predict response to radiotherapy. Global measures of genomic instability also show exciting capacity to predict survival outcomes following EBRT. There is also an urgent clinical need for biomarkers to predict the radiotherapy fraction sensitivity of different prostate tumours and preclinical studies point to possible candidates. Finally, the increased resolution of next generation sequencing (NGS) is likely to enable yet more precise molecular predictions of radiotherapy response and fraction sensitivity. PMID:26504789

[Stereotactic lung radiotherapy: Technical setting up on Novalis Tx® and single centre prospective study of the 100 first malignant pulmonary nodules treated at centre Jean-Perrin].

PubMed

Bellière-Calandry, A; Dupic, G; Magnier, F; Chassin, V; Dedieu, V; Lapeyre, M

2017-06-01

Description of the treatment technique of stereotactic lung radiotherapy on Novalis Tx ® and prospective study of the first 100 pulmonary nodules treated at centre Jean-Perrin (France). From October 2012 to December 2015, 100 inoperable pulmonary nodules (62 stage I non-small-cell lung cancer and 38 metastases) of 90 patients with a mean age of 68.2 years (range: 46-89 years) were prospectively treated with dynamic arctherapy on Novalis Tx ® . Mean gross tumour and planning target volumes were respectively 6.9 cm 3 (range: 0.2-31.4 cm 3 ) and 38.7 cm 3 (range: 1.7-131 cm 3 ), which correspond to diameters equal to 2.3cm and 4.2cm. Prescribed doses to the 80% isodose line were 54Gy in three fractions for peripheral non-small-cell lung cancer, 50Gy in five fractions for central non-small-cell lung cancer and 45Gy in three fractions for lung metastases. Clinical and radiological follow-up was done every three months with RECIST criteria for efficacy and NCI-CTCAE v4 scale for toxicity. Median follow-up was 12.5 months. Complete response was observed in 23.8% of cases. Local control rates were 100% and 90.7% respectively at 12 and 24 months, with 96% at 24 months for stage I non-small-cell lung cancer. Overall survival rates of patients with stage I non-small-cell lung cancer were 77.4% and 73.5% at 12 and 24 months (median overall survival was 32 months). Diffusing capacity of the lungs for carbon monoxide corrected for alveolar volume below 40% was significantly associated to a poor prognostic factor on univariate analysis (P=0.00013). At least three deaths were due to an acute respiratory failure, which correspond to about 4.8% of grade 5 radiation pneumonitis. Overall survival rate for metastatic patients were 95.2% and 59.5% respectively at 12 and 24 months (median overall survival was 25 months); 23.3% of grade 2 or less radiation pneumonitis, 7.8% of grade 2 or less radiation dermatitis, 2.2% of asymptomatic ribs fracture and 3.3% of chest pains were observed. Stereotactic lung radiotherapy is an effective treatment for inoperable stage I non-small-cell lung cancer and lung oligometastases of well informed and selected patients. Initial respiratory state, and especially the diffusing capacity of the lungs for carbon monoxide corrected for alveolar volume, seems to be important for tolerance. Copyright © 2017 Société française de radiothérapie oncologique (SFRO). Published by Elsevier SAS. All rights reserved.

Immunosuppressive Environment in Basal Cell Carcinoma: The Role of Regulatory T Cells.

PubMed

Omland, Silje H; Nielsen, Patricia S; Gjerdrum, Lise M R; Gniadecki, Robert

2016-11-02

Interaction between tumour survival tactics and anti-tumour immune response is a major determinant for cancer growth. Regulatory T cells (T-regs) contribute to tumour immune escape, but their role in basal cell carcinoma (BCC) is not understood. The fraction of T-regs among T cells was analysed by immunohistochemistry followed by automated image analysis in facial BCC, peritumoural skin and normal, buttock skin. Quantitative real-time PCR (qRT-PCR) was performed for FOXP3 and cytokines involved in T-reg attraction and T-cell activation. T-regs comprised 45% of CD4-cells surrounding BCC. FOXP3 was highly expressed in BCC, but absent in buttock skin. Unexpectedly, expression of FOXP3 was increased in peritumoural skin, with the FOXP3/CD3 fractions exceeding those of BCC (p?=?0.0065). Transforming growth factor (TGF)-? and T-reg chemokine expression was increased in BCC and peritumoural skin, but not in buttock skin, with expression levels correlating with FOXP3. T-regs are abundantly present both in BCC and in peritumoural skin, mediating an immunosuppressed microenvironment permissive for skin cancer.

Life and death of female gametes during oogenesis and folliculogenesis.

PubMed

Krysko, Dmitri V; Diez-Fraile, Araceli; Criel, Godelieve; Svistunov, Andrei A; Vandenabeele, Peter; D'Herde, Katharina

2008-09-01

The vertebrate ovary is an extremely dynamic organ in which excessive or defective follicles are rapidly and effectively eliminated early in ontogeny and thereafter continuously throughout reproductive life. More than 99% of follicles disappear, primarily due to apoptosis of granulosa cells, and only a minute fraction of the surviving follicles successfully complete the path to ovulation. The balance between signals for cell death and survival determines the destiny of the follicles. An abnormally high rate of cell death followed by atresia can negatively affect fertility and eventually lead irreversibly to premature ovarian failure. In this review we provide a short overview of the role of programmed cell death in prenatal differentiation of the primordial germ cells and in postnatal folliculogenesis. We also discuss the issue of neo-oogenesis. Next, we highlight molecules involved in regulation of granulosa cell apoptosis. We further discuss the potential use of scores for apoptosis in granulosa cells and characteristics of follicular fluid as prognostic markers for predicting the outcome of assisted reproduction. Potential therapeutic strategies for combating premature ovarian failure are also addressed.

Inductive potential of recombinant human granulocyte colony-stimulating factor to mature neutrophils from x-irradiated human peripheral blood hematopoietic progenitor cells.

PubMed

Katsumori, Takeo; Yoshino, Hironori; Hayashi, Masako; Takahashi, Kenji; Kashiwakura, Ikuo

2009-11-01

Recombinant human granulocyte colony-stimulating factor (rhG-CSF) has been used for treatment of neutropenia. Filgrastim, Nartograstim, and Lenograstim are clinically available in Japan. However, the differences in potential benefit for radiation-induced disorder between these types of rhG-CSFs remain unknown. Therefore, the effects of three different types of rhG-CSFs on granulocyte progenitor cells and expansion of neutrophils from nonirradiated or 2 Gy X-irradiated human CD34+ hematopoietic progenitor cells were examined. For analysis of granulocyte colony-forming units (CFU-G) and a surviving fraction of CFU-G, nonirradiated or X-irradiated CD34+ cells were cultured in methylcellulose containing rhG-CSF. These cells were cultured in serum-free medium supplemented with rhG-CSF, and the expansion and characteristics of neutrophils were analyzed. All three types of rhG-CSFs increased the number of CFU-G in a dose-dependent manner; however, Lenograstim is superior to others because of CFU-G-derived colony formation at relatively low doses. The surviving fraction of CFU-G was independent of the types of rhG-CSFs. Expansion of neutrophils by rhG-CSF was largely attenuated by X-irradiation, though no significant difference in neutrophil number was observed between the three types of rhG-CSFs under both nonirradiation and X-irradiation conditions. In terms of functional characteristics of neutrophils, Lenograstim-induced neutrophils produced high levels of reactive oxygen species compared to Filgrastim, when rhG-CSF was applied to nonirradiated CD34(+) cells. In conclusion, different types of rhG-CSFs lead to different effects when rhG-CSF is applied to nonirradiated CD34+ cells, though Filgrastim, Nartograstim, and Lenograstim show equal effects on X-irradiated CD34+ cells.

Lung cancer tumorigenicity and drug resistance are maintained through ALDH(hi)CD44(hi) tumor initiating cells.

PubMed

Liu, Jing; Xiao, Zhijie; Wong, Sunny Kit-Man; Tin, Vicky Pui-Chi; Ho, Ka-Yan; Wang, Junwen; Sham, Mai-Har; Wong, Maria Pik

2013-10-01

Limited improvement in long term survival of lung cancer patients has been achieved by conventional chemotherapy or targeted therapy. To explore the potentials of tumor initiating cells (TIC)-directed therapy, it is essential to identify the cell targets and understand their maintenance mechanisms. We have analyzed the performance of ALDH/CD44 co-expression as TIC markers and treatment targets of lung cancer using well-validated in vitro and in vivo analyses in multiple established and patient-derived lung cancer cells. The ALDH(hi)CD44(hi) subset showed the highest enhancement of stem cell phenotypic properties compared to ALDH(hi)CD44(lo), ALDH(lo)CD44(hi), ALDH(lo)CD44(lo) cells and unsorted controls. They showed higher invasion capacities, pluripotency genes and epithelial-mesenchymal transition transcription factors expression, lower intercellular adhesion protein expression and higher G2/M phase cell cycle fraction. In immunosuppressed mice, the ALDH(hi)CD44(hi)xenografts showed the highest tumor induction frequency, serial transplantability, shortest latency, largest volume and highest growth rates. Inhibition of sonic Hedgehog and Notch developmental pathways reduced ALDH+CD44+ compartment. Chemotherapy and targeted therapy resulted in higher AALDH(hi)CD44(hi) subset viability and ALDH(lo)CD44(lo) subset apoptosis fraction. ALDH inhibition and CD44 knockdown led to reduced stemness gene expression and sensitization to drug treatment. In accordance, clinical lung cancers containing a higher abundance of ALDH and CD44-coexpressing cells was associated with lower recurrence-free survival. Together, results suggested theALDH(hi)CD44(hi)compartment was the cellular mediator of tumorigenicity and drug resistance. Further investigation of the regulatory mechanisms underlying ALDH(hi)CD44(hi)TIC maintenance would be beneficial for the development of long term lung cancer control.

Mouse bone marrow-derived mesenchymal stem cells inhibit leukemia/lymphoma cell proliferation in vitro and in a mouse model of allogeneic bone marrow transplant

PubMed Central

SONG, NINGXIA; GAO, LEI; QIU, HUIYING; HUANG, CHONGMEI; CHENG, HUI; ZHOU, HONG; LV, SHUQING; CHEN, LI; WANG, JIANMIN

2015-01-01

The allogeneic hematopoietic stem cell (HSC) transplantation of mesenchymal stem cells (MSCs) contributes to the reconstitution of hematopoiesis by ameliorating acute graft-versus-host disease (aGVHD). However, the role of MSCs in graft-versus-leukemia remains to be determined. In the present study, we co-cultured C57BL/6 mouse bone marrow (BM)-derived MSCs with A20 murine B lymphoma, FBL3 murine erythroleukemia and P388 murine acute lymphocytic leukemia cells. Cell proliferation, apoptosis, cell cycle progression and the amount of cytokine secretion were then measured using a Cell Counting kit-8, Annexin V/propidium iodide staining, flow cytometry and ELISA, respectively. We also established a model of allogeneic bone marrow transplantation (BMT) using BALB/c mice. Following the administration of A20 cells and MSCs, we recorded the symptoms and the survival of the mice for 4 weeks, assessed the T cell subsets present in peripheral blood, and, after the mice were sacrifice, we determined the infiltration of MSCs into the organs by histological staining. Our results revealed that the MSCs inhibited the proliferation of the mouse lymphoma and leukemia cells in vitro, leading to cell cycle arrest and reducing the secretion of interleukin (IL)-10. In our model of allogeneic BMT, the intravenous injection of MSCs into the mice injected wth A20 cells decreased the incidence of lymphoma, improved survival, increased the fraction of CD3+CD8+ T cells, decreased the fraction of CD3+CD4+ T cells and CD4+CD25+ T cells in peripheral blood, and ameliorated the manifestation of aGVHD. The results from the present study indicate that MSCs may be safe and effective when used in allogeneic BMT for the treatment of hemotological malignancies. PMID:25901937

Mouse bone marrow-derived mesenchymal stem cells inhibit leukemia/lymphoma cell proliferation in vitro and in a mouse model of allogeneic bone marrow transplant.

PubMed

Song, Ningxia; Gao, Lei; Qiu, Huiying; Huang, Chongmei; Cheng, Hui; Zhou, Hong; Lv, Shuqing; Chen, Li; Wang, Jianmin

2015-07-01

The allogeneic hematopoietic stem cell (HSC) transplantation of mesenchymal stem cells (MSCs) contributes to the reconstitution of hematopoiesis by ameliorating acute graft‑versus‑host disease (aGVHD). However, the role of MSCs in graft‑versus‑leukemia remains to be determined. In the present study, we co‑cultured C57BL/6 mouse bone marrow (BM)‑derived MSCs with A20 murine B lymphoma, FBL3 murine erythroleukemia and P388 murine acute lymphocytic leukemia cells. Cell proliferation, apoptosis, cell cycle progression and the amount of cytokine secretion were then measured using a Cell Counting kit‑8, Annexin V/propidium iodide staining, flow cytometry and ELISA, respectively. We also established a model of allogeneic bone marrow transplantation (BMT) using BALB/c mice. Following the administration of A20 cells and MSCs, we recorded the symptoms and the survival of the mice for 4 weeks, assessed the T cell subsets present in peripheral blood, and, after the mice were sacrifice, we determined the infiltration of MSCs into the organs by histological staining. Our results revealed that the MSCs inhibited the proliferation of the mouse lymphoma and leukemia cells in vitro, leading to cell cycle arrest and reducing the secretion of interleukin (IL)‑10. In our model of allogeneic BMT, the intravenous injection of MSCs into the mice injected wth A20 cells decreased the incidence of lymphoma, improved survival, increased the fraction of CD3+CD8+ T cells, decreased the fraction of CD3+CD4+ T cells and CD4+CD25+ T cells in peripheral blood, and ameliorated the manifestation of aGVHD. The results from the present study indicate that MSCs may be safe and effective when used in allogeneic BMT for the treatment of hemotological malignancies.

Fluorine-19 Labeling of Stromal Vascular Fraction Cells for Clinical Imaging Applications

PubMed Central

Rose, Laura C.; Kadayakkara, Deepak K.; Wang, Guan; Bar-Shir, Amnon; Helfer, Brooke M.; O’Hanlon, Charles F.; Kraitchman, Dara L.; Rodriguez, Ricardo L.

2015-01-01

Stromal vascular fraction (SVF) cells are used clinically for various therapeutic targets. The location and persistence of engrafted SVF cells are important parameters for determining treatment failure versus success. We used the GID SVF-1 platform and a clinical protocol to harvest and label SVF cells with the fluorinated (19F) agent CS-1000 as part of a first-in-human phase I trial (clinicaltrials.gov identifier NCT02035085) to track SVF cells with magnetic resonance imaging during treatment of radiation-induced fibrosis in breast cancer patients. Flow cytometry revealed that SVF cells consisted of 25.0% ± 15.8% CD45+, 24.6% ± 12.5% CD34+, and 7.5% ± 3.3% CD31+ cells, with 2.1 ± 0.7 × 105 cells per cubic centimeter of adipose tissue obtained. Fluorescent CS-1000 (CS-ATM DM Green) labeled 87.0% ± 13.5% of CD34+ progenitor cells compared with 47.8% ± 18.5% of hematopoietic CD45+ cells, with an average of 2.8 ± 2.0 × 1012 19F atoms per cell, determined using nuclear magnetic resonance spectroscopy. The vast majority (92.7% ± 5.0%) of CD31+ cells were also labeled, although most coexpressed CD34. Only 16% ± 22.3% of CD45−/CD31−/CD34− (triple-negative) cells were labeled with CS-ATM DM Green. After induction of cell death by either apoptosis or necrosis, >95% of 19F was released from the cells, indicating that fluorine retention can be used as a surrogate marker for cell survival. Labeled-SVF cells engrafted in a silicone breast phantom could be visualized with a clinical 3-Tesla magnetic resonance imaging scanner at a sensitivity of approximately 2 × 106 cells at a depth of 5 mm. The current protocol can be used to image transplanted SVF cells at clinically relevant cell concentrations in patients. Significance Stromal vascular fraction (SVF) cells harvested from adipose tissue offer great promise in regenerative medicine, but methods to track such cell therapies are needed to ensure correct administration and monitor survival. A clinical protocol was developed to harvest and label SVF cells with the fluorinated (19F) agent CS-1000, allowing cells to be tracked with 19F magnetic resonance imaging (MRI). Flow cytometry evaluation revealed heterogeneous 19F uptake in SVF cells, confirming the need for careful characterization. The proposed protocol resulted in sufficient 19F uptake to allow imaging using a clinical MRI scanner with point-of-care processing. PMID:26511652

Definitive hypofractionated radiotherapy for early glottic carcinoma: experience of 55Gy in 20 fractions.

PubMed

Ermiş, Ekin; Teo, Mark; Dyker, Karen E; Fosker, Chris; Sen, Mehmet; Prestwich, Robin Jd

2015-09-23

A wide variety of fractionation schedules have been employed for the treatment of early glottic cancer. The aim is to report our 10-year experience of using hypofractionated radiotherapy with 55Gy in 20 fractions at 2.75Gy per fraction. Patients treated between 2004 and 2013 with definitive radiotherapy to a dose of 55Gy in 20 fractions over 4 weeks for T1/2 N0 squamous cell carcinoma of the glottis were retrospectively identified. Patients with prior therapeutic minor surgery (eg. laser stripping, cordotomy) were included. The probabilities of local control, ultimate local control (including salvage surgery), regional control, cause specific survival (CSS) and overall survival (OS) were calculated. One hundred thirty-two patients were identified. Median age was 65 years (range 33-89). Median follow up was 72 months (range 7-124). 50 (38 %), 18 (14 %) and 64 (48 %) of patients had T1a, T1b and T2 disease respectively. Five year local control and ultimate local control rates were: overall - 85.6 % and 97.3 % respectively, T1a - 91.8 % and 100 %, T1b - 81.6 and 93.8 %, and T2 - 80.9 % and 95.8 %. Five year regional control, CSS and OS rates were 95.4 %, 95.7 % and 78.8 % respectively. There were no significant associations of covariates (e.g. T-stage, extent of laryngeal extension, histological grade) with local control on univariate analysis. Only increasing age and transglottic extension in T2 disease were significantly associated with overall survival (both p <0.01). Second primary cancers developed in 17 % of patients. 13 (9.8 %) of patients required enteral tube feeding support during radiotherapy; no patients required long term enteral nutrition. One patient required a tracheostomy due to a non-functioning larynx on long term follow up. Hypofractionated radiation therapy with a dose of 55Gy in 20 fractions for early stage glottic cancer provides high rates of local control with acceptable toxicity.

Automating Microbial Directed Evolution For Bioengineering Applications

NASA Astrophysics Data System (ADS)

Lee, A.; Demachkie, I. S.; Sardesh, N.; Arismendi, D.; Ouandji, C.; Wang, J.; Blaich, J.; Gentry, D.

2016-12-01

From a micro-biology perspective, directed evolution is a technique that uses controlled environmental pressures to select for a desired phenotype. Directed evolution has the distinct advantage over rational design of not needing extensive knowledge of the genome or pathways associated with a microorganism to induce phenotypes. However, there are currently limitations to the applicability of this technique including being time-consuming, error-prone, and dependent on existing assays that may lack selectivity for the given phenotype. The AADEC (Autonomous Adaptive Directed Evolution Chamber) system is a proof-of-concept instrument to automate and improve the technique such that directed evolution can be used more effectively as a general bioengineering tool. A series of tests using the automated system and comparable by-hand survival assay measurements have been carried out using UV-C radiation and Escherichia coli cultures in order to demonstrate the advantages of the AADEC versus traditional implementations of directed evolution such as random mutagenesis. AADEC uses UV-C exposure as both a source of environmental stress and mutagenesis, so in order to evaluate the UV-C tolerance obtained from the cultures, a manual UV-C exposure survival assay was developed alongside the device to compare the survival fractions at a fixed dosage. This survival assay involves exposing E.coli to UV-C radiation using a custom-designed exposure hood to control the flux and dose. Surviving cells are counted then transferred to the next iteration and so on for several iterations to calculate the survival fractions for each exposure iteration. This survival assay primarily serves as a baseline for the AADEC device, allowing quantification of the differences between the AADEC system over the manual approach. The primary data of comparison is survival fractions; this is obtained by optical density and plate counts in the manual assay and by optical density growth curve fits pre- and post-exposure in the automated case. This data can then be compiled to calculate trends over the iterations to characterize increasing UV-C resistance of the E.coli strains. The observed trends are statistically indistinguishable through several iterations from both sources.

ATM inhibitor KU-55933 increases the TMZ responsiveness of only inherently TMZ sensitive GBM cells.

PubMed

Nadkarni, Aditi; Shrivastav, Meena; Mladek, Ann C; Schwingler, Paul M; Grogan, Patrick T; Chen, Junjie; Sarkaria, Jann N

2012-12-01

Ataxia telangiectasia mutated (ATM) kinase is critical in sensing and repairing DNA double-stranded breaks (DSBs) such as those induced by temozolomide (TMZ). ATM deficiency increases TMZ sensitivity, which suggests that ATM inhibitors may be effective TMZ sensitizing agents. In this study, the TMZ sensitizing effects of 2 ATM specific inhibitors were studied in established and xenograft-derived glioblastoma (GBM) lines that are inherently sensitive to TMZ and derivative TMZ-resistant lines. In parental U251 and U87 glioma lines, the addition of KU-55933 to TMZ significantly increased cell killing compared to TMZ alone [U251 survival: 0.004 ± 0.0015 vs. 0.08 ± 0.01 (p < 0.001), respectively, and U87 survival: 0.02 ± 0.005 vs. 0.04 ± 0.002 (p < 0.001), respectively] and also elevated the fraction of cells arrested in G2/M [U251 G2/M fraction: 61.8 ± 1.1 % vs. 35 ± 0.8 % (p < 0.001), respectively, and U87 G2/M fraction 25 ± 0.2 % vs.18.6 ± 0.4 % (p < 0.001), respectively]. In contrast, KU-55933 did not sensitize the resistant lines to TMZ, and neither TMZ alone or combined with KU-55933 induced a G2/M arrest. While KU-55933 did not enhance TMZ induced Chk1/Chk2 activation, it increased TMZ-induced residual γ-H2AX foci in the parental cells but not in the TMZ resistant cells. Similar sensitization was observed with either KU-55933 or CP-466722 combined with TMZ in GBM12 xenograft line but not in GBM12TMZ, which is resistant to TMZ due to MGMT overexpression. These findings are consistent with a model where ATM inhibition suppresses the repair of TMZ-induced DSBs in inherently TMZ-sensitive tumor lines, which suggests an ATM inhibitor potentially could be deployed with an improvement in the therapeutic window when combined with TMZ.

Stochastic Predictions of Cell Kill During Stereotactic Ablative Radiation Therapy: Do Hypoxia and Reoxygenation Really Matter?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Harriss-Phillips, Wendy M., E-mail: wharrphil@gmail.com; School of Chemistry and Physics, University of Adelaide, Adelaide, South Australia; Bezak, Eva

Purpose: To simulate stereotactic ablative radiation therapy on hypoxic and well-oxygenated in silico tumors, incorporating probabilistic parameter distributions and linear-quadratic versus linear-quadratic-cubic methodology and the evaluation of optimal fractionation schemes using biological effective dose (BED{sub α/β=10} {sub or} {sub 3}) comparisons. Methods and Materials: A temporal tumor growth and radiation therapy algorithm simulated high-dose external beam radiation therapy using stochastic methods. Realistic biological proliferative cellular hierarchy and pO{sub 2} histograms were incorporated into the 10{sup 8}-cell tumor model, with randomized radiation therapy applied during continual cell proliferation and volume-based gradual tumor reoxygenation. Dose fractions ranged from 6-35 Gy, with predictive outcomes presentedmore » in terms of the total doses (converted to BED) required to eliminate all cells that could potentially regenerate the tumor. Results: Well-oxygenated tumor control BED{sub 10} outcomes were not significantly different for high-dose versus conventional radiation therapy (BED{sub 10}: 79-84 Gy; Equivalent Dose in 2 Gy fractions with α/β of 10: 66-70 Gy); however, total treatment times decreased from 7 down to 1-3 weeks. For hypoxic tumors, an additional 28 Gy (51 Gy BED{sub 10}) was required, with BED{sub 10} increasing with dose per fraction due to wasted dose in the final fraction. Fractions of 9 Gy compromised well for total treatment time and BED, with BED{sub 10}:BED{sub 3} of 84:176 Gy for oxic and 132:278 Gy for non-reoxygenating hypoxic tumors. Initial doses of 12 Gy followed by 6 Gy further increased the therapeutic ratio. When delivering ≥9 Gy per fraction, applying reoxygenation and/or linear-quadratic-cubic cell survival both affected tumor control doses by a significant 1-2 fractions. Conclusions: The complex temporal dynamics of tumor oxygenation combined with probabilistic cell kinetics in the modeling of radiation therapy requires sophisticated stochastic modeling to predict tumor cell kill. For stereotactic ablative radiation therapy, high doses in the first week followed by doses that are more moderate may be beneficial because a high percentage of hypoxic cells could be eradicated early while keeping the required BED{sub 10} relatively low and BED{sub 3} toxicity to tolerable levels.« less

Ionizing irradiation not only inactivates clonogenic potential in primary normal human diploid lens epithelial cells but also stimulates cell proliferation in a subset of this population.

PubMed

Fujimichi, Yuki; Hamada, Nobuyuki

2014-01-01

Over the past century, ionizing radiation has been known to induce cataracts in the crystalline lens of the eye, but its mechanistic underpinnings remain incompletely understood. This study is the first to report the clonogenic survival of irradiated primary normal human lens epithelial cells and stimulation of its proliferation. Here we used two primary normal human cell strains: HLEC1 lens epithelial cells and WI-38 lung fibroblasts. Both strains were diploid, and a replicative lifespan was shorter in HLEC1 cells. The colony formation assay demonstrated that the clonogenic survival of both strains decreases similarly with increasing doses of X-rays. A difference in the survival between two strains was actually insignificant, although HLEC1 cells had the lower plating efficiency. This indicates that the same dose inactivates the same fraction of clonogenic cells in both strains. Intriguingly, irradiation enlarged the size of clonogenic colonies arising from HLEC1 cells in marked contrast to those from WI-38 cells. Such enhanced proliferation of clonogenic HLEC1 cells was significant at ≥2 Gy, and manifested as increments of ≤2.6 population doublings besides sham-irradiated controls. These results suggest that irradiation of HLEC1 cells not only inactivates clonogenic potential but also stimulates proliferation of surviving uniactivated clonogenic cells. Given that the lens is a closed system, the stimulated proliferation of lens epithelial cells may not be a homeostatic mechanism to compensate for their cell loss, but rather should be regarded as abnormal. This is because these findings are consistent with the early in vivo evidence documenting that irradiation induces excessive proliferation of rabbit lens epithelial cells and that suppression of lens epithelial cell divisions inhibits radiation cataractogenesis in frogs and rats. Thus, our in vitro model will be useful to evaluate the excessive proliferation of primary normal human lens epithelial cells that may underlie radiation cataractogenesis, warranting further investigations.

Comparison of Biological Effectiveness of Carbon-Ion Beams in Japan and Germany

DOE Office of Scientific and Technical Information (OSTI.GOV)

Uzawa, Akiko; Ando, Koichi; Koike, Sachiko

2009-04-01

Purpose: To compare the biological effectiveness of 290 MeV/amu carbon-ion beams in Chiba, Japan and in Darmstadt, Germany, given that different methods for beam delivery are used for each. Methods and Materials: Murine small intestine and human salivary gland tumor (HSG) cells exponentially growing in vitro were irradiated with 6-cm width of spread-out Bragg peaks (SOBPs) adjusted to achieve nearly identical beam depth-dose profiles at the Heavy-Ion Medical Accelerator in Chiba, and the SchwerIonen Synchrotron in Darmstadt. Cell kill efficiencies of carbon ions were measured by colony formation for HSG cells and jejunum crypts survival in mice. Cobalt-60 {gamma} raysmore » were used as the reference radiation. Isoeffective doses at given survivals were used for relative biological effectiveness (RBE) calculations and interinstitutional comparisons. Results: Isoeffective D{sub 10} doses (mean {+-} standard deviation) of HSG cells ranged from 2.37 {+-} 0.14 Gy to 3.47 {+-} 0.19 Gy for Chiba and from 2.31 {+-} 0.11 Gy to 3.66 {+-} 0.17 Gy for Darmstadt. Isoeffective D{sub 10} doses of gut crypts after single doses ranged from 8.25 {+-} 0.17 Gy to 10.32 {+-} 0.14 Gy for Chiba and from 8.27 {+-} 0.10 Gy to 10.27 {+-} 0.27 Gy for Darmstadt, whereas isoeffective D{sub 30} doses after three fractionated doses were 9.89 {+-} 0.17 Gy through 13.70 {+-} 0.54 Gy and 10.14 {+-} 0.20 Gy through 13.30 {+-} 0.41 Gy for Chiba and Darmstadt, respectively. Overall difference of RBE between the two facilities was 0-5% or 3-7% for gut crypt survival or HSG cell kill, respectively. Conclusion: The carbon-ion beams at the National Institute of Radiological Sciences in Chiba, Japan and the Gesellschaft fuer Schwerionenforschung in Darmstadt, Germany are biologically identical after single and daily fractionated irradiation.« less

Survival of Pseudomonas aeruginosa exposed to sunlight resembles the phenom of persistence.

PubMed

Forte Giacobone, Ana F; Oppezzo, Oscar J

2015-01-01

During exposure of Pseudomonas aeruginosa stationary phase cells to natural solar radiation, a reduction in the rate of loss of bacterial viability was observed when survival fractions were lower than 1/10,000. This reduction was independent of the growth medium used and of the initial bacterial concentration, and was also observed when irradiation was performed with artificial UVA radiation (365nm, 47Wm(-2)). These results indicate the presence of a small bacterial subpopulation with increased tolerance to radiation. Such a tolerance is non-heritable, since survival curves comparable to those of the parental strain were obtained from survivors to long-term exposure to radiation. The radiation response described here resembles the phenomenon called persistence, which consists of the presence of a small subpopulation of slow-growing cells which are able to survive antibiotic treatment within a susceptible bacterial population. The condition of persister cells is acquired via a reversible switch and involves active defense systems towards oxidative stress. Persistence is probably responsible for biphasic responses of bacteria to several stress conditions, one of which may be exposure to sunlight. The models currently used to analyze the lethal action of sunlight overestimate the effect of high-dose irradiation. These models could be improved by including the potential formation of persister cells. Copyright © 2014 Elsevier B.V. All rights reserved.

Cancer chemopreventive and anticancer evaluation of extracts and fractions from marine macro- and microorganisms collected from Twilight Zone waters around Guam.

PubMed

Schupp, Peter J; Kohlert-Schupp, Claudia; Whitefield, Susanna; Engemann, Anna; Rohde, Sven; Hemscheidt, Thomas; Pezzuto, John M; Kondratyuk, Tamara P; Park, Eun-Jung; Marler, Laura; Rostama, Bahman; Wright, Anthony D

2009-12-01

The cancer chemopreventive and cytotoxic properties of 50 extracts derived from Twilight Zone (50-150 m) sponges, gorgonians and associated bacteria, together with 15 extracts from shallow water hard corals, as well as 16 fractions derived from the methanol solubles of the Twilight Zone sponge Suberea sp, were assessed in a series of bioassays. These assays included: Induction of quinone reductase (QR), inhibition of TNF-alpha activated nuclear factor kappa B (NFkappaB), inhibition of aromatase, interaction with retinoid X receptor (RXR), inhibition of nitric oxide (NO) synthase, inhibition 2,2-diphenyl-1-picrylhydrazyl radical scavenging (DPPH), and inhibition of HL-60 and MCF-7 cell proliferation. The results of these assays showed that at least 10 extracts and five fractions inhibited NFkappaB by greater than 60%, two extracts and two fractions inhibited DPPH by more than 50%, nine extracts and two fractions affected the survival of HL-60 cells, no extracts or fractions affected RXR, three extracts and six fractions affected quinone reductase (QR), three extracts and 12 fractions significantly inhibited aromatase, four extracts and five fractions inhibited nitric oxide synthase, and one extract and no fractions inhibited the growth of MCF-7 cells by more than 95%. These data revealed the tested samples to have many and varied activities, making them, as shown with the extract of the Suberea species, useful starting points for further fractionation and purification. Moreover, the large number of samples demonstrating activity in only one or sometimes two assays accentuates the potential of the Twilight Zone, as a largely unexplored habitat, for the discovery of selectively bioactive compounds. The overall high hit rate in many of the employed assays is considered to be a significant finding in terms of "normal" hit rates associated with similar samples from shallower depths.

Isogentisin--a novel compound for the prevention of smoking-caused endothelial injury.

PubMed

Schmieder, Astrid; Schwaiger, Stefan; Csordas, Adam; Backovic, Aleksandar; Messner, Barbara; Wick, Georg; Stuppner, Hermann; Bernhard, David

2007-10-01

The best strategy in the fight against tobacco-induced diseases is prevention. However, more than one billion people around the world are smokers. Most of these people will develop or already suffer from tobacco-induced diseases. In this project, we screened 22 natural alpine plant extracts for their potential to protect human vascular endothelial cells from cigarette smoke-induced cell damage. Extracts from Gentiana lutea (Yellow Gentian) proved to be effective, and were therefore subjected to bio-guided fractionation. Although our analyses suggest that G. lutea contains several active principles, fractions containing isogentisin (1,3-dihydroxy-7-methoxyxanthone), and pure isogentisin, were most effective. In experiments addressing the nature of the mechanism of protection, we were able to show that isogentisin does not directly interfere with cigarette smoke chemicals. Addition of isogentisin to the cells as long as 4.5h after exposure to cigarette smoke chemicals protected endothelial cells from cell death. Finally, detailed analyses of intracellular oxidative stress and protein oxidation suggest that isogentisin promotes cell survival by activating cellular repair functions.

WNT activation by lithium abrogates TP53 mutation associated radiation resistance in medulloblastoma.

PubMed

Zhukova, Nataliya; Ramaswamy, Vijay; Remke, Marc; Martin, Dianna C; Castelo-Branco, Pedro; Zhang, Cindy H; Fraser, Michael; Tse, Ken; Poon, Raymond; Shih, David J H; Baskin, Berivan; Ray, Peter N; Bouffet, Eric; Dirks, Peter; von Bueren, Andre O; Pfaff, Elke; Korshunov, Andrey; Jones, David T W; Northcott, Paul A; Kool, Marcel; Pugh, Trevor J; Pomeroy, Scott L; Cho, Yoon-Jae; Pietsch, Torsten; Gessi, Marco; Rutkowski, Stefan; Bognár, Laszlo; Cho, Byung-Kyu; Eberhart, Charles G; Conter, Cecile Faure; Fouladi, Maryam; French, Pim J; Grajkowska, Wieslawa A; Gupta, Nalin; Hauser, Peter; Jabado, Nada; Vasiljevic, Alexandre; Jung, Shin; Kim, Seung-Ki; Klekner, Almos; Kumabe, Toshihiro; Lach, Boleslaw; Leonard, Jeffrey R; Liau, Linda M; Massimi, Luca; Pollack, Ian F; Ra, Young Shin; Rubin, Joshua B; Van Meir, Erwin G; Wang, Kyu-Chang; Weiss, William A; Zitterbart, Karel; Bristow, Robert G; Alman, Benjamin; Hawkins, Cynthia E; Malkin, David; Clifford, Steven C; Pfister, Stefan M; Taylor, Michael D; Tabori, Uri

2014-12-24

TP53 mutations confer subgroup specific poor survival for children with medulloblastoma. We hypothesized that WNT activation which is associated with improved survival for such children abrogates TP53 related radioresistance and can be used to sensitize TP53 mutant tumors for radiation. We examined the subgroup-specific role of TP53 mutations in a cohort of 314 patients treated with radiation. TP53 wild-type or mutant human medulloblastoma cell-lines and normal neural stem cells were used to test radioresistance of TP53 mutations and the radiosensitizing effect of WNT activation on tumors and the developing brain. Children with WNT/TP53 mutant medulloblastoma had higher 5-year survival than those with SHH/TP53 mutant tumours (100% and 36.6%±8.7%, respectively (p<0.001)). Introduction of TP53 mutation into medulloblastoma cells induced radioresistance (survival fractions at 2Gy (SF2) of 89%±2% vs. 57.4%±1.8% (p<0.01)). In contrast, β-catenin mutation sensitized TP53 mutant cells to radiation (p<0.05). Lithium, an activator of the WNT pathway, sensitized TP53 mutant medulloblastoma to radiation (SF2 of 43.5%±1.5% in lithium treated cells vs. 56.6±3% (p<0.01)) accompanied by increased number of γH2AX foci. Normal neural stem cells were protected from lithium induced radiation damage (SF2 of 33%±8% for lithium treated cells vs. 27%±3% for untreated controls (p=0.05). Poor survival of patients with TP53 mutant medulloblastoma may be related to radiation resistance. Since constitutive activation of the WNT pathway by lithium sensitizes TP53 mutant medulloblastoma cells and protect normal neural stem cells from radiation, this oral drug may represent an attractive novel therapy for high-risk medulloblastomas.

Metronomic chemotherapy prevents therapy-induced stromal activation and induction of tumor-initiating cells

PubMed Central

Chan, Tze-Sian; Pai, Vincent C.; Tan, Kok-Tong; Yen, Chia-Jui; Hsu, Shu-Ching; Chen, Wei-Yu; Shan, Yan-Shen; Lee, Michael T.; Chu, Jui-Mei

2016-01-01

Although traditional chemotherapy kills a fraction of tumor cells, it also activates the stroma and can promote the growth and survival of residual cancer cells to foster tumor recurrence and metastasis. Accordingly, overcoming the host response induced by chemotherapy could substantially improve therapeutic outcome and patient survival. In this study, resistance to treatment and metastasis has been attributed to expansion of stem-like tumor-initiating cells (TICs). Molecular analysis of the tumor stroma in neoadjuvant chemotherapy–treated human desmoplastic cancers and orthotopic tumor xenografts revealed that traditional maximum-tolerated dose chemotherapy, regardless of the agents used, induces persistent STAT-1 and NF-κB activity in carcinoma-associated fibroblasts. This induction results in the expression and secretion of ELR motif–positive (ELR+) chemokines, which signal through CXCR-2 on carcinoma cells to trigger their phenotypic conversion into TICs and promote their invasive behaviors, leading to paradoxical tumor aggression after therapy. In contrast, the same overall dose administered as a low-dose metronomic chemotherapy regimen largely prevented therapy-induced stromal ELR+ chemokine paracrine signaling, thus enhancing treatment response and extending survival of mice carrying desmoplastic cancers. These experiments illustrate the importance of stroma in cancer therapy and how its impact on treatment resistance could be tempered by altering the dosing schedule of systemic chemotherapy. PMID:27881732

Development of thermotolerance in CHO cells: modification by procaine.

PubMed

Rastogi, D; Henle, K J; Nagle, W A; Moss, A J; Neilan, B A; Rastogi, S P

1987-01-01

We have tested the reported ability of procaine to inhibit the induction and the development of thermotolerance in Chinese hamster ovary cells. Thermotolerance was induced either by hyperthermia alone (10 min, 45 degrees C) or by combining hyperthermia and procaine (5 min, 45 degrees C + 10 mM procaine) with heating times adjusted to yield similar cell survival after the conditioning treatments. Both the kinetics of thermotolerance development in fresh medium without procaine and the magnitude of thermotolerance 6 h after heat conditioning were similar for the two treatment groups. Development of thermotolerance in the presence of procaine was tested by adding the drug at 5 or 10 mM to culture medium between, but not during two fractionated heat treatments. Thermotolerance development was observed even in the presence of 10 mM procaine, but only if cell survival was corrected for the 37 degrees C-procaine toxicity. Complete survival curves of cells incubated for 6 h at 37 degrees C in 7.5 mM procaine between heat conditioning and test heating showed a D0 that was only 35 per cent lower than that of thermotolerant controls. The data are consistent with the reported sensitization to heat killing by procaine, but show that thermotolerance induction and development were only minimally perturbed by procaine.

Microdosimetric Modeling of Biological Effectiveness for Boron Neutron Capture Therapy Considering Intra- and Intercellular Heterogeneity in 10B Distribution.

PubMed

Sato, Tatsuhiko; Masunaga, Shin-Ichiro; Kumada, Hiroaki; Hamada, Nobuyuki

2018-01-17

We here propose a new model for estimating the biological effectiveness for boron neutron capture therapy (BNCT) considering intra- and intercellular heterogeneity in 10 B distribution. The new model was developed from our previously established stochastic microdosimetric kinetic model that determines the surviving fraction of cells irradiated with any radiations. In the model, the probability density of the absorbed doses in microscopic scales is the fundamental physical index for characterizing the radiation fields. A new computational method was established to determine the probability density for application to BNCT using the Particle and Heavy Ion Transport code System PHITS. The parameters used in the model were determined from the measured surviving fraction of tumor cells administrated with two kinds of 10 B compounds. The model quantitatively highlighted the indispensable need to consider the synergetic effect and the dose dependence of the biological effectiveness in the estimate of the therapeutic effect of BNCT. The model can predict the biological effectiveness of newly developed 10 B compounds based on their intra- and intercellular distributions, and thus, it can play important roles not only in treatment planning but also in drug discovery research for future BNCT.

Estimating and modeling the cure fraction in population-based cancer survival analysis.

PubMed

Lambert, Paul C; Thompson, John R; Weston, Claire L; Dickman, Paul W

2007-07-01

In population-based cancer studies, cure is said to occur when the mortality (hazard) rate in the diseased group of individuals returns to the same level as that expected in the general population. The cure fraction (the proportion of patients cured of disease) is of interest to patients and is a useful measure to monitor trends in survival of curable disease. There are 2 main types of cure fraction model, the mixture cure fraction model and the non-mixture cure fraction model, with most previous work concentrating on the mixture cure fraction model. In this paper, we extend the parametric non-mixture cure fraction model to incorporate background mortality, thus providing estimates of the cure fraction in population-based cancer studies. We compare the estimates of relative survival and the cure fraction between the 2 types of model and also investigate the importance of modeling the ancillary parameters in the selected parametric distribution for both types of model.

Low-level laser effects on bacterial cultures submitted to heat stress

NASA Astrophysics Data System (ADS)

Gonçalves, E. M.; Guimarães, O. R.; Geller, M.; Paoli, F.; Fonseca, A. S.

2016-06-01

Low-level lasers have been used worldwide to treat a number of diseases, pain relief, and wound healing. Some studies demonstrated that low-level laser radiations induce effects depending on the physiological state and DNA repair mechanisms of cells. In this work we evaluated the effects of low-level red and infrared lasers on Escherichia coli cells deficient in SOS responses submitted to heat stress. Exponential and stationary E. coli cultures of wild type (AB1157), RecA deficient (AB2463) and LexA deficient (AB2494), both SOS response deficient, were exposed to low-level red and infrared lasers at different fluences and submitted to heat stress (42 °C, 20 min). After that, cell survival and morphology were evaluated. Previous exposure to red, but not infrared lasers, increases survival fractions and decreases the area ratios of E. coli AB1157 cells submitted to heat stress. Our research suggests that a low-level red laser increases cell viability and protects cells from morphological alteration in E. coli cultures submitted to heat stress depending on laser wavelength and SOS response.

In vitro myotoxic effects of bupivacaine on rhabdomyosarcoma cells, immortalized and primary muscle cells.

PubMed

Metterlein, Thomas; Hoffmann, Petra; Späth, Ruth; Gruber, Michael; Graf, Bernhard M; Zink, Wolfgang

2015-01-01

Rhabdomyosarcoma is a rare malignant skeletal muscle tumor. It mainly occurs in children and young adults and has an unsatisfactory prognosis. Prior studies showed a direct myotoxic effect of bupivacaine on differentiated muscle cells in vitro and in vivo. Exact mechanisms of this myotoxicity are still not fully understood, but a myotoxic effect on malignant muscle tumor cells has not been examined so far. Thus, the aim of this study was to examine if bupivacaine has cytotoxic effects on rhabdomyosarcoma cells, immortalized muscle cells and differentiated muscle cells. Cell lines of rhabdomyosarcoma cells, immortalized muscle cells and differentiated muscle cells were established. After microscopic identification, cells were exposed to various concentrations of bupivacaine (500, 1,000, 1,750, 2,500 and 5,000 ppm) for 1 and 2 h, respectively. 24 and 28 h after incubation the cultures were stained with propidium iodid and analyzed by flow cytometry. The fraction of dead cells was calculated for each experiment and the concentration with 50% cell survival (IC50) was computed. Cell groups as well as incubation and recovery time were compared (ANOVA/Bonferroni p < 0.01). The total number of cultured cells was similar for the different local anesthetics and examined concentrations. Increasing concentrations of bupivacaine led to a decrease in survival of muscle cells. IC50 was highest for immortalized cells, followed by rhabdomyosarcoma cells and differentiated cells. Exposure time, but not recovery time, had an influence on survival. Bupivacaine has clear but different cytotoxic effects on various muscle cell types in vitro. Differentiated primary cells seem to be more vulnerable than tumor cells possibly because of more differentiated intracellular structures.

Biological effects of low-dose-rate irradiation of pancreatic carcinoma cells in vitro using 125I seeds

PubMed Central

Wang, Zhong-Min; Lu, Jian; Zhang, Li-Yun; Lin, Xiao-Zhu; Chen, Ke-Min; Chen, Zhi-Jin; Liu, Fen-Ju; Yan, Fu-Hua; Teng, Gao-Jun; Mao, Ai-Wu

2015-01-01

AIM: To determine the mechanism of the radiation-induced biological effects of 125I seeds on pancreatic carcinoma cells in vitro. METHODS: SW1990 and PANC-1 pancreatic cancer cell lines were cultured in DMEM in a suitable environment. Gray’s model of iodine-125 (125I) seed irradiation was used. In vitro, exponential phase SW1990, and PANC-1 cells were exposed to 0, 2, 4, 6, and 8 Gy using 125I radioactive seeds, with an initial dose rate of 12.13 cGy/h. A clonogenic survival experiment was performed to observe the ability of the cells to maintain their clonogenic capacity and to form colonies. Cell-cycle and apoptosis analyses were conducted to detect the apoptosis percentage in the SW1990 and PANC-1 cells. DNA synthesis was measured via a tritiated thymidine (3H-TdR) incorporation experiment. After continuous low-dose-rate irradiation with 125I radioactive seeds, the survival fractions at 2 Gy (SF2), percentage apoptosis, and cell cycle phases of the SW1990 and PANC-1 pancreatic cancer cell lines were calculated and compared. RESULTS: The survival fractions of the PANC-1 and SW1990 cells irradiated with 125I seeds decreased exponentially as the dose increased. No significant difference in SF2 was observed between SW1990 and PANC-1 cells (0.766 ± 0.063 vs 0.729 ± 0.045, P < 0.05). The 125I seeds induced a higher percentage of apoptosis than that observed in the control in both the SW1990 and PANC-1 cells. The rate of apoptosis increased with increasing radiation dosage. The percentage of apoptosis was slightly higher in the SW1990 cells than in the PANC-1 cells. Dose-dependent G2/M cell-cycle arrest was observed after 125I seed irradiation, with a peak value at 6 Gy. As the dose increased, the percentage of G2/M cell cycle arrest increased in both cell lines, whereas the rate of DNA incorporation decreased. In the 3H-TdR incorporation experiment, the dosimetry results of both the SW1990 and PANC-1 cells decreased as the radiation dose increased, with a minimum at 6 Gy. There were no significant differences in the dosimetry results of the two cell lines when they were exposed to the same dose of radiation. CONCLUSION: The pancreatic cancer cell-killing effects induced by 125I radioactive seeds mainly occurred via apoptosis and G2/M cell cycle arrest. PMID:25741139

Clinical outcomes using carbon-ion radiotherapy and dose-volume histogram comparison between carbon-ion radiotherapy and photon therapy for T2b-4N0M0 non-small cell lung cancer-A pilot study.

PubMed

Shirai, Katsuyuki; Kawashima, Motohiro; Saitoh, Jun-Ichi; Abe, Takanori; Fukata, Kyohei; Shigeta, Yuka; Irie, Daisuke; Shiba, Shintaro; Okano, Naoko; Ohno, Tatsuya; Nakano, Takashi

2017-01-01

The safety and efficacy of carbon-ion radiotherapy for advanced non-small cell lung cancer have not been established. We evaluated the clinical outcomes and dose-volume histogram parameters of carbon-ion radiotherapy compared with photon therapy in T2b-4N0M0 non-small cell lung cancer. Twenty-three patients were treated with carbon-ion radiotherapy between May 2011 and December 2015. Seven, 14, and 2 patients had T2b, T3, and T4, respectively. The median age was 78 (range, 53-91) years, with 22 male patients. There were 12 adenocarcinomas, 8 squamous cell carcinomas, 1 non-small cell lung carcinoma, and 2 clinically diagnosed lung cancers. Eleven patients were operable, and 12 patients were inoperable. Most patients (91%) were treated with carbon-ion radiotherapy of 60.0 Gy relative biological effectiveness (RBE) in 4 fractions or 64.0 Gy (RBE) in 16 fractions. Local control and overall survival rates were calculated. Dose-volume histogram parameters of normal lung and tumor coverages were compared between carbon-ion radiotherapy and photon therapies, including three-dimensional conformal radiotherapy (3DCRT) and intensity-modulated radiotherapy (IMRT). The median follow-up of surviving patients was 25 months. Three patients experienced local recurrence, and the 2-year local control rate was 81%. During follow-up, 5 patients died of lung cancer, and 1 died of intercurrent disease. The 2-year overall survival rate was 70%. Operable patients had a better overall survival rate compared with inoperable patients (100% vs. 43%; P = 0.04). There was no grade ≥2 radiation pneumonitis. In dose-volume histogram analysis, carbon-ion radiotherapy had a significantly lower dose to normal lung and greater tumor coverage compared with photon therapies. Carbon-ion radiotherapy was effectively and safely performed for T2b-4N0M0 non-small cell lung cancer, and the dose distribution was superior compared with those for photon therapies. A Japanese multi-institutional study is ongoing to prospectively evaluate these patients and establish the use of carbon-ion radiotherapy.

Crucial role of interleukin-4 in the survival of colon cancer stem cells.

PubMed

Francipane, Maria Giovanna; Alea, Mileidys Perez; Lombardo, Ylenia; Todaro, Matilde; Medema, J P; Stassi, Giorgio

2008-06-01

Colon tumors may be maintained by a rare fraction of cancer stem-like cells (CSC) that express the cell surface marker CD133. Self-renewing CSCs exhibit relatively greater resistance to clinical cytotoxic therapies and recent work suggests that this resistance may be mediated in part by an autocrine response to the immune cytokine interleukin 4 (IL-4). Blocking IL-4 signaling can sensitize CSCs to apoptotic stimuli and increase the in vivo efficacy of cytotoxic therapy. These findings suggest that inhibitors of IL-4 signaling may offer a new therapeutic tool in colon carcinoma.

TGF-β converts apoptotic stimuli into the signal for Th9 differentiation

PubMed Central

Takami, Mariko; Love, Robert B.; Iwashima, Makio

2012-01-01

Naturally arising CD4+CD25+FoxP3+ regulatory T cells (nTregs) play an essential role in maintenance of immune homeostasis and peripheral tolerance. Previously, we reported that conventional CD4+ and CD8+ T cells undergo p53-induced CD28-dependent apoptosis (PICA) when stimulated with a combination of immobilized anti-CD3 and anti-CD28 antibodies while nTregs expand robustly under the same conditions, suggesting that there is a differential survival mechanism against PICA between conventional T cells and nTregs. Here, we demonstrate that TGF-β signaling is required for nTregs to survive PICA. Conversely, when an active form of exogenous TGF-β is present, conventional T cells become resistant to PICA and undergo robust expansion instead of apoptosis, with reduction of the pro-apoptotic protein Bim and FoxO3a. A substantial fraction of PICA-resisted T cells expressed IL-9 (TH9 cells). Moreover, the presence of IL-6 along with TGF-β led to generation of TH17 cells from conventional T cells. Together, the data demonstrate a novel role for TGF-β in the homeostasis of Tregs and effector T cell differentiation/ expansion. PMID:22461692

Indirect Tumor Cell Death After High-Dose Hypofractionated Irradiation: Implications for Stereotactic Body Radiation Therapy and Stereotactic Radiation Surgery

DOE Office of Scientific and Technical Information (OSTI.GOV)

Song, Chang W., E-mail: songx001@umn.edu; Korea Institute of Radiological and Medical Sciences, Seoul; Lee, Yoon-Jin

Purpose: The purpose of this study was to reveal the biological mechanisms underlying stereotactic body radiation therapy (SBRT) and stereotactic radiation surgery (SRS). Methods and Materials: FSaII fibrosarcomas grown subcutaneously in the hind limbs of C3H mice were irradiated with 10 to 30 Gy of X rays in a single fraction, and the clonogenic cell survival was determined with in vivo–in vitro excision assay immediately or 2 to 5 days after irradiation. The effects of radiation on the intratumor microenvironment were studied using immunohistochemical methods. Results: After cells were irradiated with 15 or 20 Gy, cell survival in FSaII tumors declined for 2 to 3 daysmore » and began to recover thereafter in some but not all tumors. After irradiation with 30 Gy, cell survival declined continuously for 5 days. Cell survival in some tumors 5 days after 20 to 30 Gy irradiation was 2 to 3 logs less than that immediately after irradiation. Irradiation with 20 Gy markedly reduced blood perfusion, upregulated HIF-1α, and increased carbonic anhydrase-9 expression, indicating that irradiation increased tumor hypoxia. In addition, expression of VEGF also increased in the tumor tissue after 20 Gy irradiation, probably due to the increase in HIF-1α activity. Conclusions: Irradiation of FSaII tumors with 15 to 30 Gy in a single dose caused dose-dependent secondary cell death, most likely by causing vascular damage accompanied by deterioration of intratumor microenvironment. Such indirect tumor cell death may play a crucial role in the control of human tumors with SBRT and SRS.« less

The human stem cell hierarchy is defined by a functional dependence on Mcl-1 for self-renewal capacity.

PubMed

Campbell, Clinton J V; Lee, Jung Bok; Levadoux-Martin, Marilyne; Wynder, Tracy; Xenocostas, Anargyros; Leber, Brian; Bhatia, Mickie

2010-09-02

The molecular basis for the unique proliferative and self-renewal properties that hierarchically distinguish human stem cells from progenitors and terminally differentiated cells remains largely unknown. We report a role for the Bcl-2 family member myeloid cell leukemia-1 (Mcl-1) as an indispensable regulator of self-renewal in human stem cells and show that a functional dependence on Mcl-1 defines the human stem cell hierarchy. In vivo pharmacologic targeting of the Bcl-2 family members in human hematopoietic stem cells (HSCs) and human leukemic stem cells reduced stem cell regenerative and self-renewal function. Subsequent protein expression studies showed that, among the Bcl-2 family members, only Mcl-1 was up-regulated exclusively in the human HSC fraction on in vivo regeneration of hematopoiesis. Short hairpin RNA-knockdown of Mcl-1 in human cord blood cells did not affect survival in the HSC or hematopoietic progenitor cell fractions in vitro but specifically reduced the in vivo self-renewal function of human HSCs. Moreover, knockdown of Mcl-1 in ontogenetically primitive human pluripotent stem cells resulted in almost complete ablation of stem cell self-renewal function. Our findings show that Mcl-1 is an essential regulator of stem cell self-renewal in humans and therefore represents an axis for therapeutic interventions.

Effects of cerebrolysin on motor-neuron-like NSC-34 cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Keilhoff, Gerburg, E-mail: Gerburg.keilhoff@med.ovgu.de; Lucas, Benjamin; Pinkernelle, Josephine

Although the peripheral nervous system is capable of regeneration, this capability is limited. As a potential means of augmenting nerve regeneration, the effects of cerebrolysin (CL) – a proteolytic peptide fraction – were tested in vitro on the motor-neuron-like NSC-34 cell line and organotypic spinal cord cultures. Therefore, NSC-34 cells were subjected to mechanical stress by changing media and metabolic stress by oxygen glucose deprivation. Afterwards, cell survival/proliferation using MTT and BrdU-labeling (FACS) and neurite sprouting using ImageJ analysis were evaluated. Calpain-1, Src and α-spectrin protein expression were analyzed by Western blot. In organotypic cultures, the effect of CL onmore » motor neuron survival and neurite sprouting was tested by immunohistochemistry. CL had a temporary anti-proliferative but initially neuroprotective effect on OGD-stressed NSC-34 cells. High-dosed or repeatedly applied CL was deleterious for cell survival. CL amplified neurite reconstruction to limited extent, affected calpain-1 protein expression and influenced calpain-mediated spectrin cleavage as a function of Src expression. In organotypic spinal cord slice cultures, CL was not able to support motor neuron survival/neurite sprouting. Moreover, it hampered astroglia and microglia activities. The data suggest that CL may have only isolated positive effects on injured spinal motor neurons. High-dosed or accumulated CL seemed to have adverse effects in treatment of spinal cord injury. Further experiments are required to optimize the conditions for a safe clinical administration of CL in spinal cord injuries. - Highlights: • Cerebrolysin (CL) is anti-proliferative but initially neuroprotective in OGD-stressed NSC-34 cells. • CL amplified neurite reconstruction of NSC-34 cells. • CL affected calpain-1 expression and calpain-mediated spectrin cleavage as function of Src expression. • In organotypic spinal cord cultures, CL hampered motor neuron survival and glia activity. • Findings pose a contraindication for unchallenged use of CL in spinal cord injuries.« less

Marrow toxicity of fractionated vs. single dose total body irradiation is identical in a canine model

DOE Office of Scientific and Technical Information (OSTI.GOV)

Storb, R.; Raff, R.F.; Graham, T.

1993-03-20

The authors explored in dogs the marrow toxicity of single dose total body irradiation delivered from two opposing [sup 60]Co sources at a rate of 10 cGy/min and compared results to those seen with total body irradiation administered in 100 cGy fractions with minimum interfraction intervals of 6 hr. Dogs were not given marrow transplants. They found that 200 cGy single dose total body irradiation was sublethal, with 12 of 13 dogs showing hematopoietic recovery and survival. Seven of 21 dogs given 300 cGy single dose total body irradiation survived compared to 6 of 10 dogs given 300 cGy fractionatedmore » total body irradiation. One of 28 dogs given 400 cGy single dose total body irradiation survived compared to none of six given fractionated radiation. With granulocyte colony stimulating factor (GCSF) administered from day 0-21 after 400 cGy total body irradiation, most dogs survived with hematological recovery. Because of the almost uniform success with GCSF after 400 cGy single dose total body irradiation, a study of GCSF after 400 cGy fractionated total body irradiation was deemed not to be informative and, thus, not carried out. Additional comparisons between single dose and fractionated total body irradiation were carried out with GCSF administered after 500 and 600 cGy of total body irradiation. As with lower doses of total body irradiation, no significant survival differences were seen between the two modes of total body irradiation, and only 3 of 26 dogs studied survived with complete hematological recovery. Overall, therefore, survival among dogs given single dose total body irradiation was not different from that of dogs given fractionated total body irradiation (p = .67). Similarly, the slopes of the postirradiation declines of granulocyte and platelet counts and the rates of their recovery in surviving dogs given equal total doses of single versus fractionated total body irradiation were indistinguishable. 24 refs., 3 figs., 2 tabs.« less

The combined effects of high-energy shock waves and ionising radiation on a human bladder cancer cell line.

PubMed

Fickweiler, S; Steinbach, P; Wörle, K; Hofstädter, F

1996-01-01

The effects of high-energy shock waves (HESW) generated by an experimental Siemens lithotripter in combination with 137Cs gamma-rays were examined in vitro. Proliferation after treatment of immobilised pellets of either single cells or multicellular spheroids of the bladder cancer cell line RT4 was determined using colony-forming assays and cell cycle analysis. Surviving and cell cycle fractions were calculated for each shock wave and radiation application mode separately, and for sequential combination in different successions for the purpose of characterizing the interaction of both treatment modalities. Combination of HESW and ionising radiation turned out to act additively or slightly supra-additively on both biologic models.

Improved fat graft survival by different volume fractions of platelet-rich plasma and adipose-derived stem cells.

PubMed

Li, Feng; Guo, Weihua; Li, Kun; Yu, Mei; Tang, Wei; Wang, Hang; Tian, Weidong

2015-03-01

The success of soft-tissue augmentation is offset by the low survival rates of grafted fat tissue. Research shows that adipose-derived stem cells (ASCs) and platelet-rich plasma (PRP) are beneficial to tissue healing. To evaluate the long-term effects of different volume fractions of PRP combined with ASCs on fat graft. ASCs were isolated from human fat tissue, and PRP was obtained from human blood. Cell count kit-8 and real-time polymerase chain reaction (PCR) were used to evaluate the influence of PRP (0%, 10%, 20%, and 30%; volume/volume [v/v]) in medium on ASC proliferation and adipogenic differentiation, respectively. A novel lipoinjection consisting of granular fat, PRP, and ASCs was subcutaneously transplanted into nude mice. The grafts were volumetrically and histologically evaluated 10, 30, 60, and 90 days after transplantation. The addition of PRP improved ASC proliferation. Expression of adipogenic-related genes, peroxisome proliferator-activated receptor-γ, lipoprotein lipase, and adipophilin were up-regulated in PRP-induced ASCs. Compared with other groups, granular fat grafts formed with 20% (v/v) and 30% (v/v) PRP significantly improved residual volumes. More intact adipocytes and capillary formation, but less vacuolization, were observed in the 20% (v/v) and 30% (v/v) PRP groups at 30, 60, and 90 days. However, no significant difference was observed between the 20% (v/v) and 30% (v/v) PRP groups in retaining fat grafts and improving histology. Fat grafting with 20% (v/v) PRP and ASCs constitutes an appropriate transplantation strategy for improving graft survival and provides a potential approach for soft-tissue restoration in plastic and reconstructive surgery. © 2015 The American Society for Aesthetic Plastic Surgery, Inc. Reprints and permission: journals.permissions@oup.com.

Influence of various scavengers of •OH radicals on the radiation sensitivity of yeast and bacteria.

PubMed

Múčka, Viliam; Bláha, Pavel; Čuba, Václav; Červenák, Jaroslav

2013-12-01

To quantitatively investigate the influence of various •OH (hydroxyl radical) scavengers on the radiation sensitivity of yeast and bacteria, particularly to define the relationship between the protective effect of a scavenger and its •OH scavenging efficiency. In order to study the protective effect of •OH scavengers we used various concentrations of four scavengers (methanol, potassium formate, ethanol and ascorbic acid) in isotonic salt solutions. These solutions containing live yeast (Saccharomyces cerevisiae) or bacteria (Escherichia coli) were irradiated with (60)Co isotope γ -radiation using two different doses and dose rates. The number of surviving cells was determined prior to and after irradiation both in suspension with and without scavengers. The surviving fractions after irradiation with and without the scavenger were evaluated. The main results of the paper were: The surviving fraction increased approximately linearly within the measured interval with increasing concentration of the scavenger. The same dependences were found for the protecting effect depending on the scavenging efficiency. The slopes of these dependences (k) were found to be characteristic for each scavenger. The k value determined the degree in which the scavenging of •OH radicals participated in the protection of living cells. The protective effects of scavengers at the same scavenging efficiency were different and unique for each scavenger. No simple relation was found between the efficiency of scavenger k and the rate constant kOH of the reactions between scavengers and •OH radicals. Our results suggest that the studied scavengers effectively protected yeast and bacteria against ionizing radiation. Although the scavenging of •OH radicals seems to be important for protection of living cells, it is clearly not the only process on which the protection is based.

Molecular profiling of ALDH1+ colorectal cancer stem cells reveals preferential activation of MAPK, FAK, and oxidative stress pro-survival signalling pathways.

PubMed

Vishnubalaji, Radhakrishnan; Manikandan, Muthurangan; Fahad, Mohamed; Hamam, Rimi; Alfayez, Musaad; Kassem, Moustapha; Aldahmash, Abdullah; Alajez, Nehad M

2018-03-02

Tumour heterogeneity leads to variable clinical response and inaccurate diagnostic and prognostic assessment. Cancer stem cells (CSCs) represent a subpopulation responsible for invasion, metastasis, therapeutic resistance, and recurrence in many human cancer types. However, the true identity of colorectal cancer (CRC) SCs remains elusive. Here, we aimed to characterize and define the gene expression portrait of CSCs in CRC-model SW403 cells. We found that ALDH + positive cells are clonogenic and highly proliferative; their global gene expression profiling-based molecular signature revealed gene enrichment related to DNA damage, MAPK, FAK, oxidative stress response, and Wnt signalling. ALDH + cells showed enhanced ROS stress resistance, whereas MAPK/FAK pathway pharmacologic inhibition limited their survival. Conversely, 5-fluorouracil increased the ALDH + cell fraction among the SW403, HCT116 and SW620 CRC models. Notably, analysis of ALDH1A1 and POU5F1 expression levels in cohorts of 462 or 420 patients for overall (OS) or disease-free (DFS) survival, respectively, obtained from the Cancer Genome Atlas CRC dataset, revealed strong association between elevated expression and poor OS ( p = 0.006) and poor DFS ( p = 0.05), thus implicating ALDH1A1 and POU5F1 in CRC prognosis. Our data reveal distinct molecular signature of ALDH + CSCs in CRC and suggest pathways relevant for successful targeted therapies and management of CRC.

Enhanced ubiquitination of cytoskeletal proteins in pressure overloaded myocardium is accompanied by changes in specific E3 ligases.

PubMed

Balasubramanian, Sundaravadivel; Mani, Santhoshkumar; Shiraishi, Hirokazu; Johnston, Rebecca K; Yamane, Kentaro; Willey, Christopher D; Cooper, George; Tuxworth, William J; Kuppuswamy, Dhandapani

2006-10-01

Ubiquitin conjugation of proteins is critical for cell homeostasis and contributes to both cell survival and death. Here we studied ubiquitination of proteins in pressure overloaded (PO) myocardium in the context of cardiomyocyte survival. Analysis using a feline right ventricular pressure overload (RVPO) model revealed a robust and transient increase in ubiquitination of proteins present in the Triton X-100-insoluble fraction in 24 to 48 h PO myocardium, and confocal micrographs indicate this increase in ubiquitination occurs subsarcolemmaly near the intercalated disc area of cardiomyocytes. The ubiquitination was accompanied by changes in E3 ligases including Cbl, E6AP, Mdm2 and cIAP in the same period of PO, although atrophy-related E3 ligases, MuRF1 and MuRF3 were unaltered. Furthermore, Cbl displayed a substantial increase in both levels of expression and tyrosine phosphorylation in 48 h PO myocardium. Confocal studies revealed enrichment of Cbl at the intercalated discs of 48 h PO cardiomyocytes, as evidenced by its colocalization with N-cadherin. Although apoptosis was observed in 48 h PO myocardium by TUNEL staining, cardiomyocytes showing ubiquitin staining were not positive for TUNEL staining. Furthermore, 48 h PO resulted in the phosphorylation of inhibitor of nuclear factor kappa B (IkappaB), suggesting its ubiquitin-mediated degradation and the nuclear localization of NFkappaB for the expression of specific cell survival factors such as cIAPs. Together these data indicate that increased levels of E3 ligases that regulate cell homeostasis and promote cell survival could ubiquitinate multiple cytoskeletal protein targets and that these events that occur during the early phase of PO may contribute to both cardiomyocyte survival and hypertrophy.

Transfection effect of microbubbles on cells in superposed ultrasound waves and behavior of cavitation bubble.

PubMed

Kodama, Tetsuya; Tomita, Yukio; Koshiyama, Ken-Ichiro; Blomley, Martin J K

2006-06-01

The combination of ultrasound and ultrasound contrast agents (UCAs) is able to induce transient membrane permeability leading to direct delivery of exogenous molecules into cells. Cavitation bubbles are believed to be involved in the membrane permeability; however, the detailed mechanism is still unknown. In the present study, the effects of ultrasound and the UCAs, Optison on transfection in vitro for different medium heights and the related dynamic behaviors of cavitation bubbles were investigated. Cultured CHO-E cells mixed with reporter genes (luciferase or beta-gal plasmid DNA) and UCAs were exposed to 1 MHz ultrasound in 24-well plates. Ultrasound was applied from the bottom of the well and reflected at the free surface of the medium, resulting in the superposition of ultrasound waves within the well. Cells cultured on the bottom of 24-well plates were located near the first node (displacement node) of the incident ultrasound downstream. Transfection activity was a function determined with the height of the medium (wave traveling distance), as well as the concentration of UCAs and the exposure time was also determined with the concentration of UCAs and the exposure duration. Survival fraction was determined by MTT assay, also changes with these values in the reverse pattern compared with luciferase activity. With shallow medium height, high transfection efficacy and high survival fraction were obtained at a low concentration of UCAs. In addition, capillary waves and subsequent atomized particles became significant as the medium height decreased. These phenomena suggested cavitation bubbles were being generated in the medium. To determine the effect of UCAs on bubble generation, we repeated the experiments using crushed heat-treated Optison solution instead of the standard microbubble preparation. The transfection ratio and survival fraction showed no additional benefit when ultrasound was used. These results suggested that cavitation bubbles created by the collapse of UCAs were a key factor for transfection, and their intensities were enhanced by the interaction of the superpose ultrasound with the decreasing the height of the medium. Hypothesizing that free cavitation bubbles were generated from cavitation nuclei created by fragmented UCA shells, we carried out numerical analysis of a free spherical bubble motion in the field of ultrasound. Analyzing the interaction of the shock wave generated by a cavitation bubble and a cell membrane, we estimated the shock wave propagation distance that would induce cell membrane damage from the center of the cavitation bubble.

DNA flow cytometric analysis of primary operable breast cancer. Relation of ploidy and S-phase fraction to outcome of patients in NSABP B-04.

PubMed

Fisher, B; Gunduz, N; Costantino, J; Fisher, E R; Redmond, C; Mamounas, E P; Siderits, R

1991-10-01

Between 1971 and 1974, 1665 women with primary operable breast cancer were randomized into a National Surgical Adjuvant Breast and Bowel Project (NSABP) trial (B-04) conducted to evaluate the effectiveness of several different regimens of surgical and radiation therapy. No systemic therapy was given. Cells from archival paraffin-embedded tumor tissue taken from 398 patients were analyzed for ploidy and S-phase fraction (SPF) using flow cytometry. Characteristics and outcome of patients with satisfactory DNA histograms were comparable to those from whom no satisfactory cytometric studies were available. In patients with diploid tumors (43%), the mean SPF was 3.4% +/- 2.3%; in the aneuploid population (57%), the SPF was 7.9% +/- 6.3%. Only 29.9% +/- 17.3% of cells in aneuploid tumors were aneuploid. Diploid tumors were more likely than aneuploid tumors to be of good nuclear grade (P less than 0.001) and smaller size (P equals 0.03). More tumors with high SPF were of poor nuclear grade than were tumors with low SPF (P equals 0.002). No significant difference in 10-year disease-free survival (P equals 0.3) or survival (P equals 0.1) was found between women with diploid or aneuploid tumors. Patients with low SPF tumors had a 13% better disease-free survival (P equals 0.0006) than those with a high SPF and a 14% better survival (P equals 0.007) at 10 years than patients with high SPF tumors. After adjustment for clinical tumor size, the difference in both disease-free survival and survival between patients with high and low SPF tumors was only 10% (P equals 0.04 and 0.08, respectively). Although SPF was found to be of independent prognostic significance for disease-free survival and marginal significance for survival, it did not detect patients with such a good prognosis as to preclude their receiving chemotherapy. The overall survival of patients with low SPF was only 53% at 10 years. These findings and those of others indicate that additional studies are necessary before tumor ploidy and SPF can be used to select patients who should or should not receive systemic therapy.

Association of Survival With Shorter Time to Radiation Therapy After Surgery for US Patients With Head and Neck Cancer.

PubMed

Harris, Jeremy P; Chen, Michelle M; Orosco, Ryan K; Sirjani, Davud; Divi, Vasu; Hara, Wendy

2018-04-01

Shortening the time from surgery to the start of radiation (TS-RT) is a consideration for physicians and patients. Although the National Comprehensive Cancer Network recommends radiation to start within 6 weeks, a survival benefit with this metric remains controversial. To determine the association of delayed TS-RT with overall survival (OS) using a large cancer registry. In this observational cohort study, 25 216 patients with nonmetastatic stages III to IV head and neck cancer were identified from the National Cancer Database (NCDB). Patients received definitive surgery followed by adjuvant radiation therapy, with an interval duration defined as TS-RT. Overall survival as a function of TS-RT and the effect of clinicopathologic risk factors and accelerated fractionation. We identified 25 216 patients with nonmetastatic squamous cell carcinoma of the head and neck. There were 18 968 (75%) men and 6248 (25%) women and the mean (SD) age of the cohort was 59 (10.9) years. Of the 25 216 patients, 9765 (39%) had a 42-days or less TS-RT and 4735 (19%) had a 43- to 49-day TS-RT. Median OS was 10.5 years (95% CI, 10.0-11.1 years) for patients with a 42-days or less TS-RT, 8.2 years (95% CI, 7.4-8.6 years; absolute difference, -2.4 years, 95% CI, -1.5 to -3.2 years) for patients with a 43- to 49-day TS-RT, and 6.5 years (95% CI, 6.1-6.8 years; absolute difference, -4.1 years, 95% CI, -3.4 to -4.7 years) for those with a 50-days or more TS-RT. Multivariable analysis found that compared with a 42-days or less TS-RT, there was not a significant increase in mortality with a 43- to 49-day TS-RT (HR, 0.98; 95% CI, 0.93-1.04), although there was for a TS-RT of 50 days or more (HR, 1.07; 95% CI, 1.02-1.12). A significant interaction was identified between TS-RT and disease site. Subgroup effect modeling found that a delayed TS-RT of 7 days resulted in significantly worse OS for patients with tonsil tumors (HR, 1.22; 95% CI, 1.05-1.43) though not other tumor subtypes. Accelerated fractionation of 5.2 fractions or more per week was associated with improved survival (HR, 0.93; 95% CI, 0.87-0.99) compared with standard fractionation. Delayed TS-RT of 50 days or more was associated with worse overall survival. The multidisciplinary care team should focus on shortening TS-RT to improve survival. Unavoidable delays may be an indication for accelerated fractionation or other dose intensification strategies.

A Phase I Study of Chemoradiotherapy With Use of Involved-Field Conformal Radiotherapy and Accelerated Hyperfractionation for Stage III Non-Small Cell Lung Cancer: WJTOG 3305

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tada, Takuhito, E-mail: tada@msic.med.osaka-cu.ac.jp; Department of Radiology, Izumi Municipal Hospital, Izumi; Chiba, Yasutaka

2012-05-01

Purpose: A Phase I study to determine a recommended dose of thoracic radiotherapy using accelerated hyperfractionation for unresectable non-small-cell lung cancer was conducted. Methods and Materials: Patients with unresectable Stage III non-small-cell lung cancer were treated intravenously with carboplatin (area under the concentration curve 2) and paclitaxel (40 mg/m{sup 2}) on Days 1, 8, 15, and 22 with concurrent twice-daily thoracic radiotherapy (1.5 Gy per fraction) beginning on Day 1 followed by two cycles of consolidation chemotherapy using carboplatin (area under the concentration curve 5) and paclitaxel (200 mg/m{sup 2}). Total doses were 54 Gy in 36 fractions, 60 Gymore » in 40 fractions, 66 Gy in 44 fractions, and 72 Gy in 48 fractions at Levels 1 to 4. The dose-limiting toxicity, defined as Grade {>=}4 esophagitis and neutropenic fever and Grade {>=}3 other nonhematologic toxicities, was monitored for 90 days. Results: Of 26 patients enrolled, 22 patients were assessable for response and toxicity. When 4 patients entered Level 4, enrollment was closed to avoid severe late toxicities. Dose-limiting toxicities occurred in 3 patients. They were Grade 3 neuropathy at Level 1 and Level 3 and Grade 3 infection at Level 1. However, the maximum tolerated dose was not reached. The median survival time was 28.6 months for all patients. Conclusions: The maximum tolerated dose was not reached, although the dose of radiation was escalated to 72 Gy in 48 fractions. However, a dose of 66 Gy in 44 fractions was adopted for this study because late toxicity data were insufficient.« less

Discrepancies between patterns of potentially lethal damage repair in the RIF-1 tumor system in vitro and in vivo

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rasey, J.S.; Nelson, N.J.

1983-01-01

Repair of potentially lethal damage (PLD) was studied in the RIF-1 tumor system in several different growth states in vivo. Exponentially growing, fed plateau, and unfed plateau cells in cell culture as well as small and large subcutaneous or intramuscular tumors were investigated. Large single doses of radiation followed by variable repair times as well as graded doses of radiation to generate survival curves immediately after irradiation or after full repair were investigated. All repair-promoting conditions studied in vitro (delayed subculture, exposure of cells to depleted growth medium after irradiation) increased surviving fraction after a single dose. The D/sub 0/more » of the cell survival curve was also increased by these procedures. No PLD repair was observed for any tumors irradiated in vivo and maintained in the animal for varying times prior to assay in vitro. The nearly 100% cell yield obtained when this tumor is prepared as a single-cell suspension for colony formation, the representative cell sample obtained, and the constant cell yield per gram as a function of time postirradiation suggest that this discrepancy is not an artifact of the assay system. The most logical explanation of these data and information on radiocurability of this neoplasm is that PLD repair, which is so frequently demonstrated in vitro, may not be a major factor in the radioresponse of this tumor when left in situ.« less

Discrepancies between patterns of potentially lethal damage repair in the RIF-1 tumor system in vitro and in vivo

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rasey, J.S.; Nelson, N.J.

1983-01-01

Repair of potentially lethal damage (PLD) was studied in the RIF-1 tumor system in several different growth states in vivo and in vitro. Exponentially growing, fed plateau, and unfed plateau cells in cell culture as well as small and large subcutaneous or intramuscular tumors were investigated. Large single doses of radiation followed by variable repair times as well as graded doses of radiation to generate survival curves immediately after irradiation or after full repair were investigated. All repair-promoting conditions studied in vitro (delayed subculture, exposure of cells to depleted growth medium after irradiation) increased surviving fraction after a single dose.more » The D0 of the cell survival curve was also increased by these procedures. No PLD repair was observed for any tumors irradiated in vivo and maintained in the animal for varying times prior to assay in vitro. The nearly 100% cell yield obtained when this tumor is prepared as a single-cell suspension for colony formation, the representative cell sample obtained, and the constant cell yield per gram as a function of time postirradiation suggest that this discrepancy is not an artifact of the assay system. The most logical explanation of these data and information on radiocurability of this neoplasm is that PLD repair, which is so frequently demonstrated in vitro, may not be a major factor in the radioresponse of this tumor when left in situ.« less

Role of dynamin-related protein 1-mediated mitochondrial fission in resistance of mouse C2C12 myoblasts to heat injury.

PubMed

Yu, Tianzheng; Deuster, Patricia; Chen, Yifan

2016-12-15

Understanding how skeletal muscles respond to high temperatures may help develop strategies for improving exercise tolerance and preventing heat injury. Mitochondria regulate cell survival by constantly changing their morphology through fusion and fission in response to environmental stimuli. Little is known about the involvement of mitochondrial dynamics in tolerance of skeletal muscle against heat stress. Mild heat acclimation and moderate heat shock appear to have different effects on the mitochondrial morphology and fission protein Drp1 in skeletal muscle cells. Mitochondrial integrity plays a key role in cell survival under heat stress. The regulation of mitochondrial morphology is closely coupled to cell survival during stress. We examined changes in the mitochondrial morphology of mouse C2C12 skeletal muscle cells in response to heat acclimation and heat shock exposure. Acclimated cells showed a greater survival rate during heat shock exposure than non-acclimated cells, and were characterized by long interconnected mitochondria and reduced expression of dynamin-related protein 1 (Drp1) for their mitochondrial fractions. Exposure of C2C12 muscle cells to heat shock led to apoptotic death featuring activation of caspase 3/7, release of cytochrome c and loss of cell membrane integrity. Heat shock also caused excessive mitochondrial fragmentation, loss of mitochondrial membrane potential and production of reactive oxygen species in C2C12 cells. Western blot and immunofluorescence image analysis revealed translocation of Drp1 to mitochondria from the cytosol in C2C12 cells exposed to heat shock. Mitochondrial division inhibitor 1 or Drp1 gene silencer reduced mitochondrial fragmentation and increased cell viability during exposure to heat shock. These results suggest that Drp1-dependent mitochondrial fission may regulate susceptibility to heat-induced apoptosis in muscle cells and that Drp1 may serve as a target for the prevention of heat-related injury. Published 2016. This article is a U.S. Government work and is in the public domain in the USA.

Role of dynamin‐related protein 1‐mediated mitochondrial fission in resistance of mouse C2C12 myoblasts to heat injury

PubMed Central

Yu, Tianzheng; Deuster, Patricia

2016-01-01

Key points Understanding how skeletal muscles respond to high temperatures may help develop strategies for improving exercise tolerance and preventing heat injury.Mitochondria regulate cell survival by constantly changing their morphology through fusion and fission in response to environmental stimuli. Little is known about the involvement of mitochondrial dynamics in tolerance of skeletal muscle against heat stress.Mild heat acclimation and moderate heat shock appear to have different effects on the mitochondrial morphology and fission protein Drp1 in skeletal muscle cells. Mitochondrial integrity plays a key role in cell survival under heat stress. Abstract The regulation of mitochondrial morphology is closely coupled to cell survival during stress. We examined changes in the mitochondrial morphology of mouse C2C12 skeletal muscle cells in response to heat acclimation and heat shock exposure. Acclimated cells showed a greater survival rate during heat shock exposure than non‐acclimated cells, and were characterized by long interconnected mitochondria and reduced expression of dynamin‐related protein 1 (Drp1) for their mitochondrial fractions. Exposure of C2C12 muscle cells to heat shock led to apoptotic death featuring activation of caspase 3/7, release of cytochrome c and loss of cell membrane integrity. Heat shock also caused excessive mitochondrial fragmentation, loss of mitochondrial membrane potential and production of reactive oxygen species in C2C12 cells. Western blot and immunofluorescence image analysis revealed translocation of Drp1 to mitochondria from the cytosol in C2C12 cells exposed to heat shock. Mitochondrial division inhibitor 1 or Drp1 gene silencer reduced mitochondrial fragmentation and increased cell viability during exposure to heat shock. These results suggest that Drp1‐dependent mitochondrial fission may regulate susceptibility to heat‐induced apoptosis in muscle cells and that Drp1 may serve as a target for the prevention of heat‐related injury. PMID:27730652

Assessment of the in vitro cytotoxicity and in vivo anti-tumor activity of the alcoholic stem bark extract/fractions of Mimusops elengi Linn.

PubMed

Kumar, Harish; Savaliya, Mihir; Biswas, Subhankar; Nayak, Pawan G; Maliyakkal, Naseer; Manjunath Setty, M; Gourishetti, Karthik; Pai, K Sreedhara Ranganath

2016-08-01

Various parts of Mimusops elengi Linn. (Sapotaceae) have been used widely in traditional Indian medicine for the treatment of pain, inflammation and wounds. The study was conducted to explore the use of stem bark of M. elengi on pharmacological grounds and to evaluate the scientific basis of cytotoxic and anti-tumor activity. Extract/fractions were prepared and in vitro cytotoxicity was assessed using SRB assay. Most effective fractions were subjected to fluorescence microscopy based acridine orange/ethidium bromide (AO/EB) and Hoechst 33342 staining to determine apoptosis induction and DNA fragmentation assay. Comet and micronuclei assay were performed to assess genotoxicity. Cell cycle analysis was also performed. In vivo anti-tumor potential was evaluated by Ehrlich ascites carcinoma (EAC) model in mice. The alcoholic stem bark extract of M. elengi along with four fractions showed potential in vitro cytotoxicity in SRB assay. Of these, dichloromethane and ethyl acetate fractions were selected for further studies. The fractions revealed apoptosis inducing potential in AO/EB and Hoechst 33342 staining, which was further confirmed by DNA fragmentation assay. Genotoxic potential was revealed by comet and micronuclei assay. Fractions also exhibited specific cell cycle inhibition in G0/G1 phase. In EAC model, ethyl acetate fraction along with the standard (cisplatin) effectively reduced the increase in body weight compared to control and improved mean survival time. Both fractions were able to restore the altered hematological and biochemical parameters. Hence, M. elengi stem bark may be a possible therapeutic candidate having cytotoxic and anti-tumor potential.

Antioxidant, anti-inflammatory and anti-septic potential of phenolic acids and flavonoid fractions isolated from Lolium multiflorum.

PubMed

Choi, Ki-Choon; Son, Young-Ok; Hwang, Jung-Min; Kim, Beom-Tae; Chae, Minseon; Lee, Jeong-Chae

2017-12-01

Interest has recently renewed in using Lolium multiflorum Lam. (Poaceae) (called Italian ryegrass; IRG) silage as an antioxidant and anti-inflammatory diet. This study investigated the antioxidant, anti-inflammatory and anti-septic potential of IRG silage and identified the primary components in IRG active fractions. Total 16 fractions were separated from the chloroform-soluble extract of IRG aerial part using Sephadex LH-20 column before HPLC analysis. Antioxidant and anti-inflammatory activities of the fractions at doses of 0-100 μg/mL were investigated using various cell-free and cell-mediated assay systems. To explore anti-septic effect of IRG fractions, female ICR and BALB/c mice orally received 40 mg/kg of phenolic acid and flavonoid-rich active fractions F 7 and F 8 every other day for 10 days, respectively, followed by LPS challenge. The active fractions showed greater antioxidant and anti-inflammatory potential compared with other fractions. IC 50 values of F 7 and F 8 to reduce LPS-stimulated NO and TNF-α production were around 15 and 30 μg/mL, respectively. Comparison of retention times with authentic compounds through HPLC analysis revealed the presence of caffeic acid, ferulic acid, myricetin and kaempferol in the fractions as primary components. These fractions inhibited LPS-stimulated MAPK and NF-κB activation. Supplementation with F 7 or F 8 improved the survival rates of mice to 70 and 60%, respectively, in LPS-injected mice and reduced near completely serum TNF-α and IL-6 levels. This study highlights antioxidant, anti-inflammatory and anti-septic activities of IRG active fractions, eventually suggesting their usefulness in preventing oxidative damage and inflammatory disorders.

Radiation-Induced Growth Retardation and Microstructural and Metabolite Abnormalities in the Hippocampus

PubMed Central

Zawaski, Janice A.; Sahnoune, Iman

2016-01-01

Cranial radiotherapy (CRT) increases survival in pediatric brain-tumor patients but can cause deleterious effects. This study evaluates the acute and long-term impact of CRT delivered during childhood/adolescence on the brain and body using a rodent model. Rats received CRT, either 4 Gy fractions × 5 d (fractionated) or a cumulative dose of 20 Gy (single dose) at 28 d of age. Animals were euthanized 1 d, 5 d, or 3.5 mo after CRT. The 3.5 mo group was imaged prior to euthanasia. At 3.5 mo, we observed significant growth retardation in irradiated animals, versus controls, and the effects of single dose on brain and body weights were more severe than fractionated. Acutely single dose significantly reduced body weight but increased brain weight, whereas fractionation significantly reduced brain but not body weights, versus controls. CRT suppressed cell proliferation in the hippocampal subgranular zone acutely. Fractional anisotropy (FA) in the fimbria was significantly lower in the single dose versus controls. Hippocampal metabolite levels were significantly altered in the single dose animals, reflecting a heightened state of inflammation that was absent in the fractionated. Our findings indicate that despite the differences in severity between the doses they both demonstrated an effect on cell proliferation and growth retardation, important factors in pediatric CRT. PMID:27242931

Radiation-Induced Growth Retardation and Microstructural and Metabolite Abnormalities in the Hippocampus.

PubMed

Rodgers, Shaefali P; Zawaski, Janice A; Sahnoune, Iman; Leasure, J Leigh; Gaber, M Waleed

2016-01-01

Cranial radiotherapy (CRT) increases survival in pediatric brain-tumor patients but can cause deleterious effects. This study evaluates the acute and long-term impact of CRT delivered during childhood/adolescence on the brain and body using a rodent model. Rats received CRT, either 4 Gy fractions × 5 d (fractionated) or a cumulative dose of 20 Gy (single dose) at 28 d of age. Animals were euthanized 1 d, 5 d, or 3.5 mo after CRT. The 3.5 mo group was imaged prior to euthanasia. At 3.5 mo, we observed significant growth retardation in irradiated animals, versus controls, and the effects of single dose on brain and body weights were more severe than fractionated. Acutely single dose significantly reduced body weight but increased brain weight, whereas fractionation significantly reduced brain but not body weights, versus controls. CRT suppressed cell proliferation in the hippocampal subgranular zone acutely. Fractional anisotropy (FA) in the fimbria was significantly lower in the single dose versus controls. Hippocampal metabolite levels were significantly altered in the single dose animals, reflecting a heightened state of inflammation that was absent in the fractionated. Our findings indicate that despite the differences in severity between the doses they both demonstrated an effect on cell proliferation and growth retardation, important factors in pediatric CRT.

Response of the RIF-1 tumor in vitro and in C3H/Km mice to x-radiation (cell survival, regrowth delay, and tumor control), chemotherapeutic agents, and activated macrophages

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brown, J.M.; Twentyman, P.R.; Zamvil, S.S.

1980-03-01

The radiation response of logarithmic growth phase and fed plateau phase RIF-1 cells in vitro was found to be characterized by D/sub 0/ values of 110 and 133 rads and extrapolation numbs of 36 and 28, respectively. The response of the tumor in vivo to X-irradiation in nonanesthetized mice showed a dependence on the tumor implantation site. In the leg muscle, the response indicated that most cells were at an intermediate level of oxygenation, whereas in the subcutaneous tissue of the flank, the response of the tumor indicated that it had a small fraction of hypoxic cells of maximum radioresistance.more » Misonidazole radiosensitized the leg-implanted tumor as measured both by cell survival and regrowth delay. The tumor was relatively insensitive to a single dose of 1,3-bis(2-chloroethyl)-1-nitrosourea, sensitive to a single dose of cis-platinum, and highly sensitive to a single dose of cyclophosphamide.« less

On the probability of cure for heavy-ion radiotherapy

NASA Astrophysics Data System (ADS)

Hanin, Leonid; Zaider, Marco

2014-07-01

The probability of a cure in radiation therapy (RT)—viewed as the probability of eventual extinction of all cancer cells—is unobservable, and the only way to compute it is through modeling the dynamics of cancer cell population during and post-treatment. The conundrum at the heart of biophysical models aimed at such prospective calculations is the absence of information on the initial size of the subpopulation of clonogenic cancer cells (also called stem-like cancer cells), that largely determines the outcome of RT, both in an individual and population settings. Other relevant parameters (e.g. potential doubling time, cell loss factor and survival probability as a function of dose) are, at least in principle, amenable to empirical determination. In this article we demonstrate that, for heavy-ion RT, microdosimetric considerations (justifiably ignored in conventional RT) combined with an expression for the clone extinction probability obtained from a mechanistic model of radiation cell survival lead to useful upper bounds on the size of the pre-treatment population of clonogenic cancer cells as well as upper and lower bounds on the cure probability. The main practical impact of these limiting values is the ability to make predictions about the probability of a cure for a given population of patients treated to newer, still unexplored treatment modalities from the empirically determined probability of a cure for the same or similar population resulting from conventional low linear energy transfer (typically photon/electron) RT. We also propose that the current trend to deliver a lower total dose in a smaller number of fractions with larger-than-conventional doses per fraction has physical limits that must be understood before embarking on a particular treatment schedule.

Early and Late Chromosome Damages in Human Lymphocytes Induced by Gamma Rays and Fe Ions

NASA Technical Reports Server (NTRS)

Sunagawa, Mayumi; Zhang, Ye; Yeshitla, Samrawit; Kadhim, Munira; Wilson, Bobby; Wu, Honglu

2014-01-01

Chromosomal translocations and inversions are considered stable, and cells containing these types of chromosome aberrations can survive multiple cell divisions. An efficient method to detect an inversion is multi-color banding fluorescent in situ hybridization (mBAND) which allows identification of both inter- and intrachromosome aberrations simultaneously. Post irradiation, chromosome aberrations may also arise after multiple cell divisions as a result of genomic instability. To investigate the stable or late-arising chromosome aberrations induced after radiation exposure, we exposed human lymphocytes to gamma rays and Fe ions ex vivo, and cultured the cells for multiple generations. Chromosome aberrations were analyzed in cells collected at first mitosis and at several time intervals during the culture period post irradiation. With gamma irradiation, about half of the damages observed at first mitosis remained after 7 day- and 14 day- culture, suggesting the transmissibility of damages to the surviving progeny. Detailed analysis of chromosome break ends participating in exchanges revealed a greater fraction of break ends involved in intrachromosome aberrations in the 7- and 14-day samples in comparison to the fraction at first mitosis. In particular, simple inversions were found at 7 and 14 days, but not at the first mitosis, suggesting that some of the aberrations might be formed days post irradiation. In contrast, at the doses that produced similar frequencies of gamma-induced chromosome aberrations as observed at first mitosis, a significantly lower yield of aberrations remained at the same population doublings after Fe ion exposure. At these equitoxic doses, more complex type aberrations were observed for Fe ions, indicating that Fe ion-induced initial chromosome damages are more severe and may lead to cell death. Comparison between low and high doses of Fe ion irradiation in the induction of late damages will also be discussed.

Autophagic cell death induced by reactive oxygen species is involved in hyperthermic sensitization to ionizing radiation in human hepatocellular carcinoma cells.

PubMed

Yuan, Guang-Jin; Deng, Jun-Jian; Cao, De-Dong; Shi, Lei; Chen, Xin; Lei, Jin-Ju; Xu, Xi-Ming

2017-08-14

To investigate whether autophagic cell death is involved in hyperthermic sensitization to ionizing radiation in human hepatocellular carcinoma cells, and to explore the underlying mechanism. Human hepatocellular carcinoma cells were treated with hyperthermia and ionizing radiation. MTT and clonogenic assays were performed to determine cell survival. Cell autophagy was detected using acridine orange staining and flow cytometric analysis, and the expression of autophagy-associated proteins, LC3 and p62, was determined by Western blot analysis. Intracellular reactive oxygen species (ROS) were quantified using the fluorescent probe DCFH-DA. Treatment with hyperthermia and ionizing radiation significantly decreased cell viability and surviving fraction as compared with hyperthermia or ionizing radiation alone. Cell autophagy was significantly increased after ionizing radiation combined with hyperthermia treatment, as evidenced by increased formation of acidic vesicular organelles, increased expression of LC3II and decreased expression of p62. Intracellular ROS were also increased after combined treatment with hyperthermia and ionizing radiation. Pretreatment with N-acetylcysteine, an ROS scavenger, markedly inhibited the cytotoxicity and cell autophagy induced by hyperthermia and ionizing radiation. Autophagic cell death is involved in hyperthermic sensitization of cancer cells to ionizing radiation, and its induction may be due to the increased intracellular ROS.

Definitive fractionated re-irradiation for local recurrence following stereotactic body radiotherapy for primary lung cancer.

PubMed

Yoshitake, Tadamasa; Shioyama, Yoshiyuki; Nakamura, Katsumasa; Sasaki, Tomonari; Ohga, Saiji; Shinoto, Makoto; Terashima, Kotaro; Asai, Kaori; Matsumoto, Keiji; Hirata, Hideki; Honda, Hiroshi

2013-12-01

To retrospectively evaluate the efficacy and safety of definitive fractionated re-irradiation for local recurrence following stereotactic body radiotherapy (SBRT) for primary lung cancer. Between April 2003 and December 2011, 398 patients with primary lung tumor underwent SBRT at the Kyushu University Hospital, and 46 out of these developed local recurrence after SBRT. Definitive fractionated re-irradiation was performed for 17 out of the 46 patients. The median dose of re-irradiation was 60 Gy/ 30 fractions. Concurrent chemotherapy was given to four patients. The median follow-up duration was 12.6 months. At one year post-re-irradiation, local progression-free survival was 33.8%; progression-free survival, 30.9%; cause-specific survival, 79.3%; and overall survival, 74.7%. No severe adverse events were observed during the follow-up. Definitive fractionated re-irradiation is thought to be a safe alternative therapy for local recurrence following SBRT, although its efficacy may be not entirely satisfactory.

Phase 2 Study of Accelerated Hypofractionated Thoracic Radiation Therapy and Concurrent Chemotherapy in Patients With Limited-Stage Small-Cell Lung Cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xia, Bing; Department of Radiation Oncology, Hangzhou Cancer Hospital, Hangzhou; Hong, Ling-Zhi

Purpose: To prospectively investigate the efficacy and toxicity of accelerated hypofractionated thoracic radiation therapy (HypoTRT) combined with concurrent chemotherapy in the treatment of limited-stage small-cell lung cancer (LS-SCLC), with the hypothesis that both high radiation dose and short radiation time are important in this setting. Methods and Materials: Patients with previously untreated LS-SCLC, Eastern Cooperative Oncology Group performance status of 0 to 2, and adequate organ function were eligible. HypoTRT of 55 Gy at 2.5 Gy per fraction over 30 days was given on the first day of the second or third cycle of chemotherapy. An etoposide/cisplatin regimen was given to 4 tomore » 6 cycles. Patients who had a good response to initial treatment were offered prophylactic cranial irradiation. The primary endpoint was the 2-year progression-free survival rate. Results: Fifty-nine patients were enrolled from July 2007 through February 2012 (median age, 58 years; 86% male). The 2-year progression-free survival rate was 49.0% (95% confidence interval [CI] 35.3%-62.7%). Median survival time was 28.5 months (95% CI 9.0-48.0 months); the 2-year overall survival rate was 58.2% (95% CI 44.5%-71.9%). The 2-year local control rate was 76.4% (95% CI 63.7%-89.1%). The severe hematologic toxicities (grade 3 or 4) were leukopenia (32%), neutropenia (25%), and thrombocytopenia (15%). Acute esophagitis and pneumonitis of grade ≥3 occurred in 25% and 10% of the patients, respectively. Thirty-eight patients (64%) received prophylactic cranial irradiation. Conclusion: Our study showed that HypoTRT of 55 Gy at 2.5 Gy per fraction daily concurrently with etoposide/cisplatin chemotherapy has favorable survival and acceptable toxicity. This radiation schedule deserves further investigation in LS-SCLC.« less

Combination of Vessel-Targeting Agents and Fractionated Radiation Therapy: The Role of the SDF-1/CXCR4 Pathway

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, Fang-Hsin; Fu, Sheng-Yung; Yang, Ying-Chieh

2013-07-15

Purpose: To investigate vascular responses during fractionated radiation therapy (F-RT) and the effects of targeting pericytes or bone marrow-derived cells (BMDCs) on the efficacy of F-RT. Methods and Materials: Murine prostate TRAMP-C1 tumors were grown in control mice or mice transplanted with green fluorescent protein-tagged bone marrow (GFP-BM), and irradiated with 60 Gy in 15 fractions. Mice were also treated with gefitinib (an epidermal growth factor receptor inhibitor) or AMD3100 (a CXCR4 antagonist) to examine the effects of combination treatment. The responses of tumor vasculatures to these treatments and changes of tumor microenvironment were assessed. Results: After F-RT, the tumormore » microvascular density (MVD) was reduced; however, the surviving vessels were dilated, incorporated with GFP-positive cells, tightly adhered to pericytes, and well perfused with Hoechst 33342, suggesting a more mature structure formed primarily via vasculogenesis. Although the gefitinib+F-RT combination affected the vascular structure by dissociating pericytes from the vascular wall, it did not further delay tumor growth. These tumors had higher MVD and better vascular perfusion function, leading to less hypoxia and tumor necrosis. By contrast, the AMD3100+F-RT combination significantly enhanced tumor growth delay more than F-RT alone, and these tumors had lower MVD and poorer vascular perfusion function, resulting in increased hypoxia. These tumor vessels were rarely covered by pericytes and free of GFP-positive cells. Conclusions: Vasculogenesis is a major mechanism for tumor vessel survival during F-RT. Complex interactions occur between vessel-targeting agents and F-RT, and a synergistic effect may not always exist. To enhance F-RT, using CXCR4 inhibitor to block BM cell influx and the vasculogenesis process is a better strategy than targeting pericytes by epidermal growth factor receptor inhibitor.« less

Intracoronary injection of CD34-cells in chronic ischemic heart failure: 7 years follow-up of the DanCell study.

PubMed

Hansen, Morten; Nyby, Sebastian; Eifer Møller, Jacob; Videbæk, Lars; Kassem, Moustapha; Barington, Torben; Thayssen, Per; Diederichsen, Axel Cosmus Pyndt

2014-01-01

Seven years ago, the DanCell study was carried out to test the hypothesis of improvement in left ventricular ejection fraction (LVEF) following repeated intracoronary injections of autologous bone marrow-derived stem cells (BMSCs) in patients suffering from chronic ischemic heart failure. In this post hoc analysis, the long-term effect of therapy is assessed. 32 patients [mean age 61 (SD ± 9), 81% males] with systolic dysfunction (LVEF 33 ± 9%) received two repeated intracoronary infusions (4 months apart) of autologous BMSCs (1,533 ± 765 × 10(6) BMSCs including 23 ± 11 × 10(6) CD34(+) cells and 14 ± 7 × 10(6) CD133(+) cells). Patients were followed for 7 years and deaths were recorded. During follow-up, 10 patients died (31%). In univariate regression analysis, the total number of BMSCs, CD34(+) cell count and CD133(+) cell count did not significantly correlate with survival (hazard ratio: 0.999, 95% CI: 0.998-1.000, p = 0.24; hazard ratio: 0.94, 95% CI: 0.88-1.01, p = 0.10, and hazard ratio: 0.96, 95% CI: 0.87-1.07, p = 0.47, respectively). After adjustment for baseline variables in multivariate regression analysis, the CD34(+) cell count was significantly associated with survival (hazard ratio: 0.90, 95% CI: 0.82-1.00, p = 0.04). Intracoronary injections of a high number of CD34(+) cells may have a beneficial effect on chronic ischemic heart failure in terms of long-term survival.

Promoting effects of adipose-derived stem cells on breast cancer cells are reversed by radiation therapy.

PubMed

Baaße, Annemarie; Juerß, Dajana; Reape, Elaine; Manda, Katrin; Hildebrandt, Guido

2018-04-01

Partial breast irradiation of early breast cancer patients after lumpectomy and the use of endogenous adipose tissue (AT) for breast reconstruction are promising applications to reduce the side effects of breast cancer therapy. This study tries to investigate the possible risks associated with these therapeutic approaches. It also examines the influence of adipose derived stem cells (ADSCs) as part of the breast cancer microenvironment, and endogenous AT on breast cancer cells following radiation therapy. ADSCs, isolated from human reduction mammoplasties of healthy female donors, exhibited multilineage capacity and specific surface markers. The promoting effects of ADSCs on the growth and survival fraction of breast cancer cells were reversed by treatment with high (8 Gy) or medium (2 Gy) radiation doses. In addition, a suppressing influence on breast cancer growth could be detected by co-culturing with irradiated ADSCs (8 Gy). Furthermore the clonogenic survival of unirradiated tumor cells was reduced by medium of irradiated ADSCs. In conclusion, radiation therapy changed the interactions of ADSCs and breast cancer cells. On the basis of our work, the importance of further studies to exclude potential risks of ADSCs in regenerative applications and radiotherapy has been emphasized.

Cure models for estimating hospital-based breast cancer survival.

PubMed

Rama, Ranganathan; Swaminathan, Rajaraman; Venkatesan, Perumal

2010-01-01

Research on cancer survival is enriched by development and application of innovative analytical approaches in relation to standard methods. The aim of the present paper is to document the utility of a mixture model to estimate the cure fraction and compare it with other approaches. The data were for 1,107 patients with locally advanced breast cancer, who completed the neo-adjuvant treatment protocol during 1990-99 at the Cancer Institute (WIA), Chennai, India. Tumour stage, post-operative pathological node (PN) and tumour residue (TR) status were studied. Event free survival probability was estimated using the Kaplan-Meier method. Cure models under proportional and non-proportional hazard assumptions following log normal distribution for survival time were used to estimate both the cure fraction and the survival function for the uncured. Event free survival at 5 and 10 years were 64.2% and 52.6% respectively and cure fraction was 47.5% for all cases together. Follow up ranged between 0-15 years and survival probabilities showed minimal changes after 7 years of follow up. TR and PN emerged as independent prognostic factors using Cox and proportional hazard (PH) cure models. Proportionality condition was violated when tumour stage was considered and it was statistically significant only under PH and not under non PH cure models. However, TR and PN continued to be independent prognostic factors after adjusting for tumour stage using the non PH cure model. A consistent ordering of cure fractions with respect to factors of PN and TR was forthcoming across tumour stages using PH and non PH cure models, but perceptible differences in survival were observed between the two. If PH conditions are violated, analysis using a non PH model is advocated and mixture cure models are useful in estimating the cure fraction and constructing survival curves for non-cures.

Moderately hypofractionated conformal radiation treatment of thoracic esophageal carcinoma.

PubMed

Ma, Jin-Bo; Wei, Lin; Chen, Er-Cheng; Qin, Guang; Song, Yi-Peng; Chen, Xiang-Ming; Hao, Chuan-Guo

2012-01-01

To prospectively assess the efficacy and safety of moderately hypofractionated conformal radiotherapy in patients with thoracic esophageal cancer. From Sept. 2002 to Oct. 2005, 150 eligible patients with T2-4N0-1M0 stage thoracic esophageal squamous cell cancers were enrolled to receive either conventional fractionated radiation (CFR) or moderately hypofractionated radiation (MHR) with a three- dimensional conformal radiation technique. Of the total, 74 received moderately hypofractionated radiation with total dose of 54-60 Gy/18-20 fractions for 3.5-4 weeks in the MHR arm, and 76 received conventional radiation with total dose of 60 Gy/30 fractions for 6 weeks in the CFR arm. Concurrent chemotherapy comprised of paclitaxel and cisplatin. Safety was evaluated, and local control and overall survival rates were calculated. Statistically significant differences between the CFR versus MHR arms were observed in local/regional failure rate (47.3% v 27.0%, P=0.034) and the percentage of patients with persistent local disease (26.3% v 10.8%, P=0.012). But 3 and 5-year overall survival rates (43.2%, 38.8% v 38.2%, 28.0%, respectively) were not different between the two arms (P=0.268). There were no significant differences in the incidences of grade 3 or higher acute toxicities (66.3% v 50.0%) and late complications rates (27.0% v 22.4%) between the MHR and CFR arms. Moderately hypofractionated, three-dimensional radiation treatment could improve the local control rate of esophageal cancer and potentially increase patient survival.

Propolis from the Stingless Bee Trigona incisa from East Kalimantan, Indonesia, Induces In Vitro Cytotoxicity and Apoptosis in Cancer Cell lines.

PubMed

Kustiawan, Paula M; Phuwapraisirisan, Preecha; Puthong, Songchan; Palaga, Tanapat; Arung, Enos T; Chanchao, Chanpen

2015-01-01

Previously, stingless bee (Trigona spp.) products from East Kalimantan, Indonesia, were successfully screened for in vitro antiproliferative activity against human cancer derived cell lines. It was established that propolis from T. incisa presented the highest in vitro cytotoxicity against the SW620 colon cancer cell line (6% cell survival in 20 μg/mL). Propolis from T. incisa was extracted with methanol and further partitioned with n-hexane, ethyl acetate and methanol. The in vitro cytotoxicity of the extracts was assessed by the MTT assay against human colon (SW620), liver (Hep-G2), gastric (KATO-III), lung (Chago) and breast (BT474) cancer derived cell lines. The active fractions were further enriched by silica gel quick column, absorption and size exclusion chromatography. The purity of each fraction was checked by thin layer chromatography. Cytotoxicity in BT-474 cells induced by cardanol compared to doxorubicin were evaluated by MTT assay, induction of cell cycle arrest and cell death by flow cytometric analysis of propidium iodide and annexin-V stained cells. A cardol isomer was found to be the major compound in one active fraction (F45) of T. incisa propolis, with a cytotoxicity against the SW620 (IC50 of 4.51±0.76 μg/mL), KATO-III (IC50 of 6.06±0.39 μg/mL), Hep-G2 (IC50 of 0.71±0.22 μg/mL), Chago I (IC50 of 0.81±0.18 μg/mL) and BT474 (IC50 of 4.28±0.14 μg/mL) cell lines. Early apoptosis (programmed cell death) of SW620 cells was induced by the cardol containing F45 fraction at the IC50 and IC80 concentrations, respectively, within 2-6 h of incubation. In addition, the F45 fraction induced cell cycle arrest at the G1 subphase. Indonesian stingless bee (T. incisa) propolis had moderately potent in vitro anticancer activity on human cancer derived cell lines. Cardol or 5-pentadecyl resorcinol was identified as a major active compound and induced apoptosis in SW620 cells in an early period (≤6 h) and cell cycle arrest at the G1 subphase. Thus, cardol is a potential candidate for cancer chemotherapy.

Proton beam irradiation inhibits the migration of melanoma cells.

PubMed

Jasińska-Konior, Katarzyna; Pochylczuk, Katarzyna; Czajka, Elżbieta; Michalik, Marta; Romanowska-Dixon, Bożena; Swakoń, Jan; Urbańska, Krystyna; Elas, Martyna

2017-01-01

In recent years experimental data have indicated that low-energy proton beam radiation might induce a difference in cellular migration in comparison to photons. We therefore set out to compare the effect of proton beam irradiation and X-rays on the survival and long-term migratory properties of two cell lines: uveal melanoma Mel270 and skin melanoma BLM. Cells treated with either proton beam or X-rays were analyzed for their survival using clonogenic assay and MTT test. Long-term migratory properties were assessed with time-lapse monitoring of individual cell movements, wound test and transpore migration, while the expression of the related proteins was measured with western blot. Exposure to proton beam and X-rays led to similar survival but the quality of the cell colonies was markedly different. More paraclones with a low proliferative activity and fewer highly-proliferative holoclones were found after proton beam irradiation in comparison to X-rays. At 20 or 40 days post-irradiation, migratory capacity was decreased more by proton beam than by X-rays. The beta-1-integrin level was decreased in Mel270 cells after both types of radiation, while vimentin, a marker of EMT, was increased in BLM cells only. We conclude that proton beam irradiation induced long-term inhibition of cellular motility, as well as changes in the level of beta-1 integrin and vimentin. If confirmed, the change in the quality, but not in the number of colonies after proton beam irradiation might favor tumor growth inhibition after fractionated proton therapy.

Survival or Revival: Long-Term Preservation Induces a Reversible Viable but Non-Culturable State in Methane-Oxidizing Bacteria

PubMed Central

Hoefman, Sven; Van Hoorde, Koenraad; Boon, Nico; Vandamme, Peter; De Vos, Paul; Heylen, Kim

2012-01-01

Knowledge on long-term preservation of micro-organisms is limited and research in the field is scarce despite its importance for microbial biodiversity and biotechnological innovation. Preservation of fastidious organisms such as methane-oxidizing bacteria (MOB) has proven difficult. Most MOB do not survive lyophilization and only some can be cryopreserved successfully for short periods. A large-scale study was designed for a diverse set of MOB applying fifteen cryopreservation or lyophilization conditions. After three, six and twelve months of preservation, the viability (via live-dead flow cytometry) and culturability (via most-probable number analysis and plating) of the cells were assessed. All strains could be cryopreserved without a significant loss in culturability using 1% trehalose in 10-fold diluted TSB (TT) as preservation medium and 5% DMSO as cryoprotectant. Several other cryopreservation and lyophilization conditions, all of which involved the use of TT medium, also allowed successful preservation but showed a considerable loss in culturability. We demonstrate here that most of these non-culturables survived preservation according to viability assessment indicating that preservation induces a viable but non-culturable (VBNC) state in a significant fraction of cells. Since this state is reversible, these findings have major implications shifting the emphasis from survival to revival of cells in a preservation protocol. We showed that MOB cells could be significantly resuscitated from the VBNC state using the TT preservation medium. PMID:22539945

Prion protein- and cardiac troponin T-marked interstitial cells from the adult myocardium spontaneously develop into beating cardiomyocytes

PubMed Central

Omatsu-Kanbe, Mariko; Nishino, Yuka; Nozuchi, Nozomi; Sugihara, Hiroyuki; Matsuura, Hiroshi

2014-01-01

Atypically-shaped cardiomyocytes (ACMs) constitute a novel subpopulation of beating heart cells found in the cultures of cardiac myocyte-removed crude fraction cells obtained from adult mouse cardiac ventricles. Although ~500 beating ACMs are observed under microscope in the cell cultures obtained from the hearts of either male or female mice, the origin of these cells in cardiac tissue has yet to be elucidated due to the lack of exclusive markers. In the present study, we demonstrate the efficacy of cellular prion protein (PrP) as a surface marker of ACMs. Cells expressing PrP at the plasma membrane in the culture of the crude fraction cells were found to develop into beating ACMs by themselves or fuse with each other to become larger multinuclear beating ACMs. Combining PrP with a cardiac-specific contractile protein cardiac troponin T (cTnT) allowed us to identify native ACMs in the mouse cardiac ventricles as either clustered or solitary cells. PrP- and cTnT-marked cells were also found in the adult, even aged, human cardiac ventricles. These findings suggest that interstitial cells marked by PrP and cTnT, native ACMs, exhibit life-long survival in the cardiac ventricles of both mice and humans. PMID:25466571

Strigolactone analogues induce apoptosis through activation of p38 and the stress response pathway in cancer cell lines and in conditionally reprogrammed primary prostate cancer cells.

PubMed

Pollock, Claire B; McDonough, Sara; Wang, Victor S; Lee, Hyojung; Ringer, Lymor; Li, Xin; Prandi, Cristina; Lee, Richard J; Feldman, Adam S; Koltai, Hinanit; Kapulnik, Yoram; Rodriguez, Olga C; Schlegel, Richard; Albanese, Christopher; Yarden, Ronit I

2014-03-30

Strigolactones are a novel class of plant hormones produced in roots and regulate shoot and root development. We have previously shown that synthetic strigolactone analogues potently inhibit growth of breast cancer cells and breast cancer stem cells. Here we show that strigolactone analogues inhibit the growth and survival of an array of cancer-derived cell lines representing solid and non-solid cancer cells including: prostate, colon, lung, melanoma, osteosarcoma and leukemic cell lines, while normal cells were minimally affected. Treatment of cancer cells with strigolactone analogues was hallmarked by activation of the stress-related MAPKs: p38 and JNK and induction of stress-related genes; cell cycle arrest and apoptosis evident by increased percentages of cells in the sub-G1 fraction and Annexin V staining. In addition, we tested the response of patient-matched conditionally reprogrammed primary prostate normal and cancer cells. The tumor cells exhibited significantly higher sensitivity to the two most potent SL analogues with increased apoptosis confirmed by PARP1 cleavage compared to their normal counterpart cells. Thus, Strigolactone analogues are promising candidates for anticancer therapy by their ability to specifically induce cell cycle arrest, cellular stress and apoptosis in tumor cells with minimal effects on growth and survival of normal cells.

Insights into the Role of Heme in the Mechanism of Action of Antimalarials

PubMed Central

Combrinck, Jill M.; Mabotha, Tebogo E.; Ncokazi, Kanyile K.; Ambele, Melvin A.; Taylor, Dale; Smith, Peter J.; Hoppe, Heinrich C.; Egan, Timothy J.

2012-01-01

Using cell fractionation and measurement of Fe(III)heme-pyridine, the antimalarial chloroquine (CQ) has been shown to cause a dose-dependent decrease in hemozoin and concomitant increase in toxic “free” heme in cultured Plasmodium falciparum that is directly correlated with parasite survival. Transmission electron microscopy techniques have further shown that heme is redistributed from the parasite digestive vacuole to the cytoplasm and that CQ disrupts hemozoin crystal growth, resulting in mosaic boundaries in the crystals formed in the parasite. Extension of the cell fractionation study to other drugs has shown that artesunate, amodiaquine, lumefantrine, mefloquine and quinine, all clinically important antimalarials, also inhibit hemozoin formation in the parasite cell, while the antifolate pyrimethamine and its combination with sulfadoxine do not. This study finally provides direct evidence in support of the hemozoin inhibition hypothesis for the mechanism of action of CQ and shows that other quinoline and related antimalarials inhibit cellular hemozoin formation. PMID:23043646

Specific action of T4 endonuclease V on damaged DNA in xeroderma pigmentosum cells in vivo. [UV radiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tanaka, K.; Hayakawa, H.; Sekiguchi, M.

1977-07-01

The specific action of T4 endonuclease V on damaged DNA in xeroderma pigmentosum cells was examined using an in vivo assay system with hemagglutinating virus of Japan (Sendai virus) inactivated by uv light. A clear dose response was observed between the level of uv-induced unscheduled DNA synthesis of xeroderma pigmentosum cells and the amount of T4 endonuclease V activity added. The T4 enzyme was unstable in human cells, and its half-life was 3 hr. Fractions derived from an extract of Escherichia coli infected with T4v/sub 1/, a mutant defective in the endonuclease V gene, showed no ability to restore themore » uv-induced unscheduled DNA synthesis of xeroderma pigmentosum cells. However, fractions derived from an extract of T4D-infected E. coli with endonuclease V activity were effective. The T4 enzyme was effective in xeroderma pigmentosum cells on DNA damaged by uv light but not in cells damaged by 4-nitroquinoline 1-oxide. The results of these experiments show that the T4 enzyme has a specific action on human cell DNA in vivo. Treatment with the T4 enzyme increased the survival of group A xeroderma pigmentosum cells after uv irradiation.« less

Dependence and independence of survival parameters on linear energy transfer in cells and tissues

PubMed Central

Ando, Koichi; Goodhead, Dudley T.

2016-01-01

Carbon-ion radiotherapy has been used to treat more than 9000 cancer patients in the world since 1994. Spreading of the Bragg peak is necessary for carbon-ion radiotherapy, and is designed based on the linear–quadratic model that is commonly used for photon therapy. Our recent analysis using in vitro cell kills and in vivo mouse tissue reaction indicates that radiation quality affects mainly the alpha terms, but much less the beta terms, which raises the question of whether this is true in other biological systems. Survival parameters alpha and beta for 45 in vitro mammalian cell lines were obtained by colony formation after irradiation with carbon ions, fast neutrons and X-rays. Relationships between survival parameters and linear energy transfer (LET) below 100 keV/μm were obtained for 4 mammalian cell lines. Mouse skin reaction and tumor growth delay were measured after fractionated irradiation. The Fe-plot provided survival parameters of the tissue reactions. A clear separation between X-rays and high-LET radiation was observed for alpha values, but not for beta values. Alpha values/terms increased with increasing LET in any cells and tissues studied, while beta did not show a systematic change. We have found a puzzle or contradiction in common interpretations of the linear-quadratic model that causes us to question whether the model is appropriate for interpreting biological effectiveness of high-LET radiation up to 500 keV/μm, probably because of inconsistency in the concept of damage interaction. A repair saturation model proposed here was good enough to fit cell kill efficiency by radiation of wide-ranged LET. A model incorporating damage complexity and repair saturation would be suitable for heavy-ion radiotherapy. PMID:27380803

Current estimates of the cure fraction: a feasibility study of statistical cure for breast and colorectal cancer.

PubMed

Stedman, Margaret R; Feuer, Eric J; Mariotto, Angela B

2014-11-01

The probability of cure is a long-term prognostic measure of cancer survival. Estimates of the cure fraction, the proportion of patients "cured" of the disease, are based on extrapolating survival models beyond the range of data. The objective of this work is to evaluate the sensitivity of cure fraction estimates to model choice and study design. Data were obtained from the Surveillance, Epidemiology, and End Results (SEER)-9 registries to construct a cohort of breast and colorectal cancer patients diagnosed from 1975 to 1985. In a sensitivity analysis, cure fraction estimates are compared from different study designs with short- and long-term follow-up. Methods tested include: cause-specific and relative survival, parametric mixture, and flexible models. In a separate analysis, estimates are projected for 2008 diagnoses using study designs including the full cohort (1975-2008 diagnoses) and restricted to recent diagnoses (1998-2008) with follow-up to 2009. We show that flexible models often provide higher estimates of the cure fraction compared to parametric mixture models. Log normal models generate lower estimates than Weibull parametric models. In general, 12 years is enough follow-up time to estimate the cure fraction for regional and distant stage colorectal cancer but not for breast cancer. 2008 colorectal cure projections show a 15% increase in the cure fraction since 1985. Estimates of the cure fraction are model and study design dependent. It is best to compare results from multiple models and examine model fit to determine the reliability of the estimate. Early-stage cancers are sensitive to survival type and follow-up time because of their longer survival. More flexible models are susceptible to slight fluctuations in the shape of the survival curve which can influence the stability of the estimate; however, stability may be improved by lengthening follow-up and restricting the cohort to reduce heterogeneity in the data. Published by Oxford University Press 2014.

Cure fraction model with random effects for regional variation in cancer survival.

PubMed

Seppä, Karri; Hakulinen, Timo; Kim, Hyon-Jung; Läärä, Esa

2010-11-30

Assessing regional differences in the survival of cancer patients is important but difficult when separate regions are small or sparsely populated. In this paper, we apply a mixture cure fraction model with random effects to cause-specific survival data of female breast cancer patients collected by the population-based Finnish Cancer Registry. Two sets of random effects were used to capture the regional variation in the cure fraction and in the survival of the non-cured patients, respectively. This hierarchical model was implemented in a Bayesian framework using a Metropolis-within-Gibbs algorithm. To avoid poor mixing of the Markov chain, when the variance of either set of random effects was close to zero, posterior simulations were based on a parameter-expanded model with tailor-made proposal distributions in Metropolis steps. The random effects allowed the fitting of the cure fraction model to the sparse regional data and the estimation of the regional variation in 10-year cause-specific breast cancer survival with a parsimonious number of parameters. Before 1986, the capital of Finland clearly stood out from the rest, but since then all the 21 hospital districts have achieved approximately the same level of survival. Copyright © 2010 John Wiley & Sons, Ltd.

Chest compression rates and survival following out-of-hospital cardiac arrest.

PubMed

Idris, Ahamed H; Guffey, Danielle; Pepe, Paul E; Brown, Siobhan P; Brooks, Steven C; Callaway, Clifton W; Christenson, Jim; Davis, Daniel P; Daya, Mohamud R; Gray, Randal; Kudenchuk, Peter J; Larsen, Jonathan; Lin, Steve; Menegazzi, James J; Sheehan, Kellie; Sopko, George; Stiell, Ian; Nichol, Graham; Aufderheide, Tom P

2015-04-01

Guidelines for cardiopulmonary resuscitation recommend a chest compression rate of at least 100 compressions/min. A recent clinical study reported optimal return of spontaneous circulation with rates between 100 and 120/min during cardiopulmonary resuscitation for out-of-hospital cardiac arrest. However, the relationship between compression rate and survival is still undetermined. Prospective, observational study. Data is from the Resuscitation Outcomes Consortium Prehospital Resuscitation IMpedance threshold device and Early versus Delayed analysis clinical trial. Adults with out-of-hospital cardiac arrest treated by emergency medical service providers. None. Data were abstracted from monitor-defibrillator recordings for the first five minutes of emergency medical service cardiopulmonary resuscitation. Multiple logistic regression assessed odds ratio for survival by compression rate categories (<80, 80-99, 100-119, 120-139, ≥140), both unadjusted and adjusted for sex, age, witnessed status, attempted bystander cardiopulmonary resuscitation, location of arrest, chest compression fraction and depth, first rhythm, and study site. Compression rate data were available for 10,371 patients; 6,399 also had chest compression fraction and depth data. Age (mean±SD) was 67±16 years. Chest compression rate was 111±19 per minute, compression fraction was 0.70±0.17, and compression depth was 42±12 mm. Circulation was restored in 34%; 9% survived to hospital discharge. After adjustment for covariates without chest compression depth and fraction (n=10,371), a global test found no significant relationship between compression rate and survival (p=0.19). However, after adjustment for covariates including chest compression depth and fraction (n=6,399), the global test found a significant relationship between compression rate and survival (p=0.02), with the reference group (100-119 compressions/min) having the greatest likelihood for survival. After adjustment for chest compression fraction and depth, compression rates between 100 and 120 per minute were associated with greatest survival to hospital discharge.

Gamma ray-induced small plaque mutants of western equine encephalitis virus

DOE Office of Scientific and Technical Information (OSTI.GOV)

Simizu, B.; Yamazaki, S.; Suzuki, K.

1973-12-01

Small plaque mutants of Western equine encephalitis virus were obtained from the surviving fractions of wild-type virus which was irradiated with gamma rays. The frequency with which small plaque mutants appeared in the surviving fraction increased with the radiation dose. These mutants were not more resistant to radiation than wild-type virus. The growth rate of a mutant, S127, was lower than that of wild-type. Clonally purified mutant virions presented two peaks in a velocity sedimentation profile; peak 1 corresponded to the peak of wild type and peak 2 moved faster than peak 1. Virions of both peaks were infectious andmore » consistently formed small plaques in chicken embryo cells. Virions reisolated from either peak and grown in chicken embryo cells also revealed two peaks in sedimentation analysis. In the electron microscope examination peak 2 proved to consist of giant form particles, each of which contained more than one nucleoid surrounded with a common envelope. Despite this remarkable morphological difference, densities of the wild-type and S127 mutant virions were similar in cesium chloride gradients. The RNAs and proteins of mutant virions could not be distinguished from those of wild types on the basis of size or change. (auth)« less

Differential Radiosensitizing Effect of Valproic Acid in Differentiation Versus Self-Renewal Promoting Culture Conditions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Debeb, Bisrat G.; Xu Wei; Mok, Henry

2010-03-01

Purpose: It has been shown that valproic acid (VA) enhances the proliferation and self-renewal of normal hematopoietic stem cells and that breast cancer stem/progenitor cells can be resistant to radiation. From these data, we hypothesized that VA would fail to radiosensitize breast cancer stem/progenitor cells grown to three-dimensional (3D) mammospheres. Methods and Materials: We used the MCF7 breast cancer cell line grown under stem cell-promoting culture conditions (3D mammosphere) and standard nonstem cell monolayer culture conditions (two-dimensional) to examine the effect of pretreatment with VA on radiation sensitivity in clonogenic survival assays and on the expression of embryonic stem cellmore » transcription factors. Results: 3D-cultured MCF-7 cells expressed higher levels of Oct4, Nanog, and Sox2. The 3D passage enriched self-renewal and increased radioresistance in the 3D mammosphere formation assays. VA radiosensitized adherent cells but radioprotected 3D cells in single-fraction clonogenic assays. Moreover, fractionated radiation sensitized VA-treated adherent MCF7 cells but did not have a significant effect on VA-treated single cells grown to mammospheres. Conclusion: We have concluded that VA might preferentially radiosensitize differentiated cells compared with those expressing stem cell surrogates and that stem cell-promoting culture is a useful tool for in vitro evaluation of novel cancer therapeutic agents and radiosensitizers.« less

Impaired Th1 immunity in ovarian cancer patients is mediated by TNFR2+ Tregs within the tumor microenvironment.

PubMed

Govindaraj, Chindu; Scalzo-Inguanti, Karen; Madondo, Mutsa; Hallo, Julene; Flanagan, Katie; Quinn, Michael; Plebanski, Magdalena

2013-10-01

Ovarian cancer is a prevalent gynecological malignancy with potent immune-suppression capabilities; regulatory T cells (Tregs) are significant contributors to this immune-suppression. As ovarian cancer patients present with high levels of TNF and Tregs expressing TNFR2 are associated with maximal suppressive capacity, we investigated TNFR2+ Tregs within these patients. Indeed, TNFR2+ Tregs from tumor-associated ascites were the most potent suppressor T cell fraction. They were abundantly present within the ascites and more suppressive than peripheral blood TNFR2+ Tregs in patients. The increased suppressive capacity can be explained by a distinct cell surface expression profile, which includes high levels of CD39, CD73, TGF-β and GARP. Additionally, CD73 expression level on TNFR2+ Tregs was inversely correlated with IFN-γ production by effector T cells. This Treg fraction can be selectively recruited into the ascites from the peripheral blood of patients. Targeting TNFR2+ Tregs may offer new approaches to enhance the poor survival rates of ovarian cancer. © 2013.

Randomized Trial of Hyperfractionation Versus Conventional Fractionation in T2 Squamous Cell Carcinoma of the Vocal Cord (RTOG 9512)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Trotti, Andy, E-mail: andy.trotti@moffitt.org; Zhang, Qiang; Bentzen, Søren M.

2014-08-01

Purpose: To compare hyperfractionation versus standard fractionation for T2N0 vocal cord carcinoma in a randomized controlled trial. Methods and Materials: Patients with T2 vocal cord cancer were stratified by substage (T2a vs T2b) and randomly assigned to receive either hyperfractionation (HFX) to 79.2 Gy in 66 fractions of 1.2 Gy given twice a day, or standard fractionation (SFX) to 70 Gy in 35 fractions given once a day. The trial was designed to detect a 55% reduction in the local failure hazard rate with 80% statistical power. Results: Between April 1996 and July 2003, a total of 250 patients were enrolled. Of 239more » patients analyzable for outcomes, 94% were male, 83% had a Karnofsky performance status of 90-100, and 62% had T2a tumor. Median follow-up for all surviving patients was 7.9 years (range, 0.6-13.1 years). The 5-year local control (LC) rate was 8 points higher but not statistically significant (P=.14 for HFX [78%] vs SFX [70%]), corresponding to a 30% hazard rate reduction. The 5-year disease-free survival (DFS) was 49% versus 40% (P=.13) and overall survival (OS) was 72% versus 63% (P=.29). HFX was associated with higher rates of acute skin, mucosal, and laryngeal toxicity. Grade 3-4 late effects were similar with a 5-year cumulative incidence of 8.5% (3.4%-13.6%) after SFX and 8.5% (3.4%-13.5%) after HFX. Conclusions: The 5-year local control was modestly higher with HFX compared to SFX for T2 glottic carcinoma, but the difference was not statistically significant. These results are consistent with prior studies of hyperfractionation showing a benefit in local control. Substaging by T2a versus T2b carries prognostic value for DFS and OS. For cost and convenience reasons other altered fractionation schedules have been adopted in routine practice.« less

Exploring factors related to metastasis free survival in breast cancer patients using Bayesian cure models.

PubMed

Jafari-Koshki, Tohid; Mansourian, Marjan; Mokarian, Fariborz

2014-01-01

Breast cancer is a fatal disease and the most frequently diagnosed cancer in women with an increasing pattern worldwide. The burden is mostly attributed to metastatic cancers that occur in one-third of patients and the treatments are palliative. It is of great interest to determine factors affecting time from cancer diagnosis to secondary metastasis. Cure rate models assume a Poisson distribution for the number of unobservable metastatic-component cells that are completely deleted from the non-metastasis patient body but some may remain and result in metastasis. Time to metastasis is defined as a function of the number of these cells and the time for each cell to develop a detectable sign of metastasis. Covariates are introduced to the model via the rate of metastatic-component cells. We used non-mixture cure rate models with Weibull and log-logistic distributions in a Bayesian setting to assess the relationship between metastasis free survival and covariates. The median of metastasis free survival was 76.9 months. Various models showed that from covariates in the study, lymph node involvement ratio and being progesterone receptor positive were significant, with an adverse and a beneficial effect on metastasis free survival, respectively. The estimated fraction of patients cured from metastasis was almost 48%. The Weibull model had a slightly better performance than log-logistic. Cure rate models are popular in survival studies and outperform other models under certain conditions. We explored the prognostic factors of metastatic breast cancer from a different viewpoint. In this study, metastasis sites were analyzed all together. Conducting similar studies in a larger sample of cancer patients as well as evaluating the prognostic value of covariates in metastasis to each site separately are recommended.

Combination Treatment of Glioblastoma by Low-Dose Radiation and Genistein.

PubMed

Atefeh, Zamanian; Vahid, Changizi; Hasan, Nedaie; Saeed, Amanpour; Mahnaz, Haddadi

2016-01-01

Gioblastoma multiforme as a chemoresistant and radioresistant malignant cell line needs to novel strategies to treatment. Low-dose hyper-radiosensitivity (LDHRS) seems to be an effective phenomenon to irradiation that can save normal brain fibroblasts. Genistein which is a soy isoflavone can be cytotoxic in some tumor cell lines. So we determined to study the effect of combining these two treatment modalities. After 30 hours incubation with Genistein in different concentrations on U87MG cell line, proliferation and clonogenicity were conducted by both clonogenic and MTT assays. A conventional 2Gy radiation dose was compared with 10 doses of 0.2Gy gamma irradiation with 3 minutes and 1 hour intervals. Finally, concurrent effect of these modalities was assessed. Based on acquired cell doubling time (30 hours), one doubling time treatment by Genistein could decrease clonogenicity. U87MG cell line exhibited HRS at low dose irradiations. 2Gy irradiation was more effective than ultra-fractionation methods in comparison with control group. All groups with 50uM concentration of Genistein showed decrease in the survival. This decrease compared with control group, in 10x0.2Gy with 3 minutes intervals plus 50uM Genistein was significant and for groups with the same dose of Genistein but along with continuous 2Gy was more significant. In one day treatment regimen, 10x0.2Gy ultra-fractionation with 3 minutes and 1 hour intervals seems to be less effective than conventional 2Gy irradiation, however adding 50uM Genistein can decrease survival more. Although 2Gy conventional dose plus 50uM Genistein was the most effective regimen. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Molecular profiling of ALDH1+ colorectal cancer stem cells reveals preferential activation of MAPK, FAK, and oxidative stress pro-survival signalling pathways

PubMed Central

Vishnubalaji, Radhakrishnan; Manikandan, Muthurangan; Fahad, Mohamed; Hamam, Rimi; Alfayez, Musaad; Kassem, Moustapha; Aldahmash, Abdullah; Alajez, Nehad M.

2018-01-01

Tumour heterogeneity leads to variable clinical response and inaccurate diagnostic and prognostic assessment. Cancer stem cells (CSCs) represent a subpopulation responsible for invasion, metastasis, therapeutic resistance, and recurrence in many human cancer types. However, the true identity of colorectal cancer (CRC) SCs remains elusive. Here, we aimed to characterize and define the gene expression portrait of CSCs in CRC-model SW403 cells. We found that ALDH+ positive cells are clonogenic and highly proliferative; their global gene expression profiling-based molecular signature revealed gene enrichment related to DNA damage, MAPK, FAK, oxidative stress response, and Wnt signalling. ALDH+ cells showed enhanced ROS stress resistance, whereas MAPK/FAK pathway pharmacologic inhibition limited their survival. Conversely, 5-fluorouracil increased the ALDH+ cell fraction among the SW403, HCT116 and SW620 CRC models. Notably, analysis of ALDH1A1 and POU5F1 expression levels in cohorts of 462 or 420 patients for overall (OS) or disease-free (DFS) survival, respectively, obtained from the Cancer Genome Atlas CRC dataset, revealed strong association between elevated expression and poor OS (p = 0.006) and poor DFS (p = 0.05), thus implicating ALDH1A1 and POU5F1 in CRC prognosis. Our data reveal distinct molecular signature of ALDH+ CSCs in CRC and suggest pathways relevant for successful targeted therapies and management of CRC. PMID:29568377

Pyruvate dehydrogenase complex and lactate dehydrogenase are targets for therapy of acute liver failure.

PubMed

Ferriero, Rosa; Nusco, Edoardo; De Cegli, Rossella; Carissimo, Annamaria; Manco, Giuseppe; Brunetti-Pierri, Nicola

2018-03-24

Acute liver failure is a rapidly progressive deterioration of hepatic function resulting in high mortality and morbidity. Metabolic enzymes can translocate to the nucleus to regulate histone acetylation and gene expression. Levels and activities of pyruvate dehydrogenase complex (PDHC) and lactate dehydrogenase (LDH) were evaluated in nuclear fractions of livers of mice exposed to various hepatotoxins including CD95-antibody, α-amanitin, and acetaminophen. Whole-genome gene expression profiling by RNA-seq was performed in livers of mice with acute liver failure and analyzed by gene ontology enrichment analysis. Cell viability was evaluated in cell lines knocked-down for PDHA1 or LDH-A and in cells incubated with the LDH inhibitor galloflavin after treatment with CD95-antibody. We evaluated whether the histone acetyltransferase inhibitor garcinol or galloflavin could reduce liver damage in mice with acute liver failure. Levels and activities of PDHC and LDH were increased in nuclear fractions of livers of mice with acute liver failure. The increase of nuclear PDHC and LDH was associated with increased concentrations of acetyl-CoA and lactate in nuclear fractions, and histone H3 hyper-acetylation. Gene expression in livers of mice with acute liver failure suggested that increased histone H3 acetylation induces the expression of genes related to damage response. Reduced histone acetylation by the histone acetyltransferase inhibitor garcinol decreased liver damage and improved survival in mice with acute liver failure. Knock-down of PDHC or LDH improved viability in cells exposed to a pro-apoptotic stimulus. Treatment with the LDH inhibitor galloflavin that was also found to inhibit PDHC, reduced hepatic necrosis, apoptosis, and expression of pro-inflammatory cytokines in mice with acute liver failure. Mice treated with galloflavin also showed a dose-response increase in survival. PDHC and LDH translocate to the nucleus, leading to increased nuclear concentrations of acetyl-CoA and lactate. This results in histone H3 hyper-acetylation and expression of damage response genes. Inhibition of PDHC and LDH reduces liver damage and improves survival in mice with acute liver failure. Thus, PDHC and LDH are targets for therapy of acute liver failure. Acute liver failure is a rapidly progressive deterioration of liver function resulting in high mortality. In experimental mouse models of acute liver failure, we found that two metabolic enzymes, namely pyruvate dehydrogenase complex and lactic dehydrogenase, translocate to the nucleus resulting in detrimental gene expression. Treatment with an inhibitor of these two enzymes was found to reduce liver damage and to improve survival. Copyright © 2018 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

Dynamic physical properties of dissociated tumor cells revealed by dielectrophoretic field-flow fractionation

PubMed Central

Shim, Sangjo; Gascoyne, Peter; Noshari, Jamileh; Stemke Hale, Katherine

2013-01-01

Metastatic disease results from the shedding of cancer cells from a solid primary tumor, their transport through the cardiovascular system as circulating tumor cells (CTCs) and their engraftment and growth at distant sites. Little is known about the properties and fate of tumor cells as they leave their growth site and travel as single cells. We applied analytical dielectrophoretic field-flow fractionation (dFFF) to study the membrane capacitance, density and hydrodynamic properties together with the size and morphology of cultured tumor cells after they were harvested and placed into single cell suspensions. After detachment, the tumor cells exhibited biophysical properties that changed with time through a process of cytoplasmic shedding whereby membrane and cytoplasm were lost. This process appeared to be distinct from the cell death mechanisms of apoptosis, anoikis and necrosis and it may explain why multiple phenotypes are seen among CTCs isolated from patients and among the tumor cells obtained from ascitic fluid of patients. The implications of dynamic biophysical properties and cytoplasmic loss for CTC migration into small blood vessels in the circulatory system, survival and gene expression are discussed. Because the total capacitance of tumor cells remained higher than blood cells even after they had shed cytoplasm, dFFF offers a compelling, antibody-independent technology for isolating viable CTCs from blood even when they are no larger than peripheral blood mononuclear cells. PMID:21691666

Impact of fraction size on locally advanced oropharyngeal and nasopharyngeal cancers treated with chemoradiation.

PubMed

Spiotto, Michael T; Koshy, Matthew

2017-05-01

Although chemoradiation regimens have used various fraction sizes, it remains unclear how differences in fraction size impact outcomes. Using the National Cancer Database, we identified patients with nasopharynx or oropharynx cancers treated between 2004 and 2012 with chemoradiation using fraction sizes of 1.8Gy (n=1612), 2Gy (n=8092) or 2.12Gy (n=1660). Comparisons between fraction sizes were made in the entire cohort and in a propensity matched cohort. Median follow-up was 38.1m. Patients receiving 2.12Gy per fraction were more likely to be treated from 2007 to 2012, to be treated at an academic center, to have T3-T4 tumors and to have oropharyngeal primaries. The 3year overall survival for patients treated with 1.8Gy, 2Gy and 2.12Gy fraction sizes was 72.9%, 77.8% and 83.3%, respectively (P<0.0001). 2.12Gy fraction size was associated with improved survival in patients with nasopharynx cancer (P=0.03), base of tongue cancer (P<0.0001) and tonsil cancer (P=0.0002). On multivariate analysis, improved survival was associated with 2.12Gy fraction sizes compared to 2Gy (HR 1.23, 95% CI 1.09-1.40, P=0.001) or 1.8Gy (HR 1.36, 95% CI 1.17-1.58; P<0.0001) fractions sizes. Chemoradiation regimens using 2.12Gy fraction sizes likely have a potential advantage in select nasopharynx and oropharynx cancer patients based on age, treatment facility and radiotherapy technique. However, it remains unclear if this survival advantage reflected improved disease control due to lack of locoregional control data. Copyright © 2017 Elsevier Ltd. All rights reserved.

Fundamental cryobiology of mouse ova and embryos

DOE Office of Scientific and Technical Information (OSTI.GOV)

Leibo, S. P.

An increasing fraction of mouse ova and embryos are killed as the rate at which they are cooled to -196/sup 0/C is increased. The survival of these cells depends not only on cooling rate, but also on the minimum subzero temperature to which the cells are cooled. Low temperature microscopy demonstrates that lethal cooling rates are coincident with those that produce intracellular ice formation, and that the lethal temperature appears to be that at which intracellular ice forms. Furthermore, the microscopy shows that ova do not dehydrate when cooled at rates that produce intracellular ice and cell death, but undergomore » substantial shrinkage when cooled at rates that produce little intracellular ice and high survival. Measurements of the water permeability of mouse ova and the temperature coefficient of that permeability can be used to test a mathematical model formulated to describe the kinetics of water loss at subzero temperatures from a hypothetical cell. The observed dehydration of ova cooled to subzero temperatures at given rates is approximately predicted by the mathematical model, although there is some quantitative discrepancy between the observed and calculated responses.« less

SU-E-T-398: Evaluation of Radiobiological Parameters Using Serial Tumor Imaging During Radiotherapy as An Inverse Ill-Posed Problem

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chvetsov, A; Sandison, G; Schwartz, J

Purpose: Combination of serial tumor imaging with radiobiological modeling can provide more accurate information on the nature of treatment response and what underlies resistance. The purpose of this article is to improve the algorithms related to imaging-based radiobilogical modeling of tumor response. Methods: Serial imaging of tumor response to radiation therapy represents a sum of tumor cell sensitivity, tumor growth rates, and the rate of cell loss which are not separated explicitly. Accurate treatment response assessment would require separation of these radiobiological determinants of treatment response because they define tumor control probability. We show that the problem of reconstruction ofmore » radiobiological parameters from serial imaging data can be considered as inverse ill-posed problem described by the Fredholm integral equation of the first kind because it is governed by a sum of several exponential processes. Therefore, the parameter reconstruction can be solved using regularization methods. Results: To study the reconstruction problem, we used a set of serial CT imaging data for the head and neck cancer and a two-level cell population model of tumor response which separates the entire tumor cell population in two subpopulations of viable and lethally damage cells. The reconstruction was done using a least squared objective function and a simulated annealing algorithm. Using in vitro data for radiobiological parameters as reference data, we shown that the reconstructed values of cell surviving fractions and potential doubling time exhibit non-physical fluctuations if no stabilization algorithms are applied. The variational regularization allowed us to obtain statistical distribution for cell surviving fractions and cell number doubling times comparable to in vitro data. Conclusion: Our results indicate that using variational regularization can increase the number of free parameters in the model and open the way to development of more advanced algorithms which take into account tumor heterogeneity, for example, related to hypoxia.« less

Estimates of cellular mutagenesis from cosmic rays

NASA Technical Reports Server (NTRS)

Cucinotta, Francis A.; Wilson, John W.

1994-01-01

A parametric track structure model is used to estimate the cross section as a function of particle velocity and charge for mutations at the hypoxanthine guanine phosphoribosyl transferase (HGPRT) locus in human fibroblast cell cultures. Experiments that report the fraction of mutations per surviving cell for human lung and skin fibroblast cells indicate small differences in the mutation cross section for these two cell lines when differences in inactivation rates between these cell lines are considered. Using models of cosmic ray transport, the mutation rate at the HGPRT locus is estimated for cell cultures in space flight and rates of about 2 to 10 x 10(exp -6) per year are found for typical spacecraft shielding. A discussion of how model assumptions may alter the predictions is also presented.

Frankincense essential oil prepared from hydrodistillation of Boswellia sacra gum resins induces human pancreatic cancer cell death in cultures and in a xenograft murine model

PubMed Central

2012-01-01

Background Regardless of the availability of therapeutic options, the overall 5-year survival for patients diagnosed with pancreatic cancer remains less than 5%. Gum resins from Boswellia species, also known as frankincense, have been used as a major ingredient in Ayurvedic and Chinese medicine to treat a variety of health-related conditions. Both frankincense chemical extracts and essential oil prepared from Boswellia species gum resins exhibit anti-neoplastic activity, and have been investigated as potential anti-cancer agents. The goals of this study are to identify optimal condition for preparing frankincense essential oil that possesses potent anti-tumor activity, and to evaluate the activity in both cultured human pancreatic cancer cells and a xenograft mouse cancer model. Methods Boswellia sacra gum resins were hydrodistilled at 78°C; and essential oil distillate fractions were collected at different durations (Fraction I at 0–2 h, Fraction II at 8–10 h, and Fraction III at 11–12 h). Hydrodistillation of the second half of gum resins was performed at 100°C; and distillate was collected at 11–12 h (Fraction IV). Chemical compositions were identified by gas chromatography–mass spectrometry (GC-MS); and total boswellic acids contents were quantified by high-performance liquid chromatography (HPLC). Frankincense essential oil-modulated pancreatic tumor cell viability and cytotoxicity were determined by colorimetric assays. Levels of apoptotic markers, signaling molecules, and cell cycle regulators expression were characterized by Western blot analysis. A heterotopic (subcutaneous) human pancreatic cancer xenograft nude mouse model was used to evaluate anti-tumor capability of Fraction IV frankincense essential oil in vivo. Frankincense essential oil-induced tumor cytostatic and cytotoxic activities in animals were assessed by immunohistochemistry. Results Longer duration and higher temperature hydrodistillation produced more abundant high molecular weight compounds, including boswellic acids, in frankincense essential oil fraactions. Human pancreatic cancer cells were sensitive to Fractions III and IV (containing higher molecular weight compounds) treatment with suppressed cell viability and increased cell death. Essential oil activated the caspase-dependent apoptotic pathway, induced a rapid and transient activation of Akt and Erk1/2, and suppressed levels of cyclin D1 cdk4 expression in cultured pancreatic cancer cells. In addition, Boswellia sacra essential oil Fraction IV exhibited anti-proliferative and pro-apoptotic activities against pancreatic tumors in the heterotopic xenograft mouse model. Conclusion All fractions of frankincense essential oil from Boswellia sacra are capable of suppressing viability and inducing apoptosis of a panel of human pancreatic cancer cell lines. Potency of essential oil-suppressed tumor cell viability may be associated with the greater abundance of high molecular weight compounds in Fractions III and IV. Although chemical component(s) responsible for tumor cell cytotoxicity remains undefined, crude essential oil prepared from hydrodistillation of Boswellia sacra gum resins might be a useful alternative therapeutic agent for treating patients with pancreatic adenocarcinoma, an aggressive cancer with poor prognosis. PMID:23237355

Adenovirus Death Protein (ADP) Is Required for Lytic Infection of Human Lymphocytes

PubMed Central

Murali, V. K.; Ornelles, D. A.; Gooding, L. R.; Wilms, H. T.; Huang, W.; Tollefson, A. E.; Wold, W. S. M.

2014-01-01

The adenovirus death protein (ADP) is expressed at late times during a lytic infection of species C adenoviruses. ADP promotes the release of progeny virus by accelerating the lysis and death of the host cell. Since some human lymphocytes survive while maintaining a persistent infection with species C adenovirus, we compared ADP expression in these cells with ADP expression in lymphocytes that proceed with a lytic infection. Levels of ADP were low in KE37 and BJAB cells, which support a persistent infection. In contrast, levels of ADP mRNA and protein were higher in Jurkat cells, which proceed with a lytic infection. Epithelial cells infected with an ADP-overexpressing virus died more quickly than epithelial cells infected with an ADP-deleted virus. However, KE37, and BJAB cells remained viable after infection with the ADP-overexpressing virus. Although the levels of ADP mRNA increased in KE37 and BJAB cells infected with the ADP-overexpressing virus, the fraction of cells with detectable ADP was unchanged, suggesting that the control of ADP expression differs between epithelial and lymphocytic cells. When infected with an ADP-deleted adenovirus, Jurkat cells survived and maintained viral DNA for greater than 1 month. These findings are consistent with the notion that the level of ADP expression determines whether lymphocytic cells proceed with a lytic or a persistent adenovirus infection. PMID:24198418

SU-F-T-497: Spatiotemporally Optimal, Personalized Prescription Scheme for Glioblastoma Patients Using the Proliferation and Invasion Glioma Model

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, M; Rockhill, J; Phillips, M

Purpose: To investigate a spatiotemporally optimal radiotherapy prescription scheme and its potential benefit for glioblastoma (GBM) patients using the proliferation and invasion (PI) glioma model. Methods: Standard prescription for GBM was assumed to deliver 46Gy in 23 fractions to GTV1+2cm margin and additional 14Gy in 7 fractions to GTV2+2cm margin. We simulated the tumor proliferation and invasion in 2D according to the PI glioma model with a moving velocity of 0.029(slow-move), 0.079(average-move), and 0.13(fast-move) mm/day for GTV2 with a radius of 1 and 2cm. For each tumor, the margin around GTV1 and GTV2 was varied to 0–6 cm and 1–3more » cm respectively. Total dose to GTV1 was constrained such that the equivalent uniform dose (EUD) to normal brain equals EUD with the standard prescription. A non-stationary dose policy, where the fractional dose varies, was investigated to estimate the temporal effect of the radiation dose. The efficacy of an optimal prescription scheme was evaluated by tumor cell-surviving fraction (SF), EUD, and the expected survival time. Results: Optimal prescription for the slow-move tumors was to use 3.0(small)-3.5(large) cm margins to GTV1, and 1.5cm margin to GTV2. For the average- and fast-move tumors, it was optimal to use 6.0cm margin for GTV1 suggesting that whole brain therapy is optimal, and then 1.5cm (average-move) and 1.5–3.0cm (fast-move, small-large) margins for GTV2. It was optimal to deliver the boost sequentially using a linearly decreasing fractional dose for all tumors. Optimal prescription led to 0.001–0.465% of the tumor SF resulted from using the standard prescription, and increased tumor EUD by 25.3–49.3% and the estimated survival time by 7.6–22.2 months. Conclusion: It is feasible to optimize a prescription scheme depending on the individual tumor characteristics. A personalized prescription scheme could potentially increase tumor EUD and the expected survival time significantly without increasing EUD to normal brain.« less

Heterogeneity of circulating epithelial tumour cells from individual patients with respect to expression profiles and clonal growth (sphere formation) in breast cancer.

PubMed

Pizon, M; Zimon, D; Carl, S; Pachmann, U; Pachmann, K; Camara, O

2013-01-01

The detection of tumour cells circulating in the peripheral blood of patients with breast cancer is a sign that cells have been able to leave the primary tumour and survive in the circulation. However, in order to form metastases, they require additional properties such as the ability to adhere, self-renew, and grow. Here we present data that a variable fraction among the circulating tumour cells detected by the Maintrac(®) approach expresses mRNA of the stem cell gene NANOG and of the adhesion molecule vimentin and is capable of forming tumour spheres, a property ascribed to tumour-initiating cells (TICs). Between ten and 50 circulating epithelial antigen-positive cells detected by the Maintrac approach were selected randomly from each of 20 patients with breast cancer before and after surgery and were isolated using automated capillary aspiration and deposited individually onto slides for expression profiling. In addition, the circulating tumour cells were cultured without isolation among the white blood cells from 39 patients with breast cancer in different stages of disease using culture methods favouring growth of epithelial cells. Although no epithelial cell adhesion molecule (EpCAM)-positive cells expressing stem cell genes or the adhesion molecule vimentin was detected before surgery, 10%-20% of the cells were found to be positive for mRNA of these genes after surgery. Tumour spheres from circulating cells of 39 patients with different stages of breast cancer were grown without previous isolation in a fraction increasing with the aggressivity of the tumour. Here we show that among the peripherally circulating tumour cells, a variable fraction is able to express stem cell and adhesion properties and can be grown into tumour spheres, a property ascribed to cells capable of initiating tumours and metastases.

Duration of Twice-Daily Thoracic Radiotherapy and Time From the Start of Any Treatment to the End of Chest Irradiation as Significant Predictors of Outcomes in Limited-Disease Small-Cell Lung Cancer.

PubMed

Morimoto, Masahiro; Okishio, Kyoichi; Akira, Masanori; Omachi, Naoki; Tamiya, Akihiro; Asami, Kazuhiro; Kawaguchi, Tomoya; Atagi, Shinji

2017-03-01

The hypothesis of this retrospective study was that the duration of twice-daily (BID) thoracic radiotherapy (TRT) and time from the start of any treatment to the end of chest irradiation (SER) would predict outcomes in limited-disease small-cell lung cancer. All 81 patients received 45 Gy in 30 fractions BID with a ≥ 6-hour interval and concurrent chemotherapy of platinum and etoposide. The median radiotherapy duration was 25 days (range, 21-38 days). The 5-year overall survival rates were 26.2% (95% confidence interval [CI], 14.3%-38.0%), and the median survival time was 30 months (95% CI, 15.5-44.5 months). Using multivariate regression analysis, the significant predictors of survival were the sum of the diameters of the primary tumor and metastatic lymph nodes, male gender, age ≥ 60 years, and the duration of BID-TRT (hazard ratio [HR], 1.15; 95% CI, 1.06-1.25; HR, 2.38; 95% CI, 1.13-5.02; HR, 2.38; 95% CI, 1.10-5.17; and HR, 1.08; 95% CI, 1.01-1.15, respectively). A total of 70 of 81 patients (86%) received radiotherapy during the first chemotherapy cycle. The median SER was 29 days (range, 21-109 days). The 5-year local control rate was 48.7% (95% CI, 33.9%-63.6%). The significant predictors of local control were the sum of the diameters of the primary tumor and metastatic lymph nodes, age ≥ 60 years, and SER (HR, 1.18; 95% CI, 1.06-1.31; HR, 4.18; 95% CI, 1.23-14.24; and HR, 1.02; 95% CI, 1-1.04, respectively). The duration of BID-TRT and SER were identified as one of the significant predictors of survival and local control in limited-disease small-cell lung cancer treated with concurrent chemoradiotherapy at 45 Gy in 30 fractions, respectively. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

The brain-penetrant clinical ATM inhibitor AZD1390 radiosensitizes and improves survival of preclinical brain tumor models.

PubMed

Durant, Stephen T; Zheng, Li; Wang, Yingchun; Chen, Kan; Zhang, Lingli; Zhang, Tianwei; Yang, Zhenfan; Riches, Lucy; Trinidad, Antonio G; Fok, Jacqueline H L; Hunt, Tom; Pike, Kurt G; Wilson, Joanne; Smith, Aaron; Colclough, Nicola; Reddy, Venkatesh Pilla; Sykes, Andrew; Janefeldt, Annika; Johnström, Peter; Varnäs, Katarina; Takano, Akihiro; Ling, Stephanie; Orme, Jonathan; Stott, Jonathan; Roberts, Caroline; Barrett, Ian; Jones, Gemma; Roudier, Martine; Pierce, Andrew; Allen, Jasmine; Kahn, Jenna; Sule, Amrita; Karlin, Jeremy; Cronin, Anna; Chapman, Melissa; Valerie, Kristoffer; Illingworth, Ruth; Pass, Martin

2018-06-01

Poor survival rates of patients with tumors arising from or disseminating into the brain are attributed to an inability to excise all tumor tissue (if operable), a lack of blood-brain barrier (BBB) penetration of chemotherapies/targeted agents, and an intrinsic tumor radio-/chemo-resistance. Ataxia-telangiectasia mutated (ATM) protein orchestrates the cellular DNA damage response (DDR) to cytotoxic DNA double-strand breaks induced by ionizing radiation (IR). ATM genetic ablation or pharmacological inhibition results in tumor cell hypersensitivity to IR. We report the primary pharmacology of the clinical-grade, exquisitely potent (cell IC 50 , 0.78 nM), highly selective [>10,000-fold over kinases within the same phosphatidylinositol 3-kinase-related kinase (PIKK) family], orally bioavailable ATM inhibitor AZD1390 specifically optimized for BBB penetration confirmed in cynomolgus monkey brain positron emission tomography (PET) imaging of microdosed 11 C-labeled AZD1390 ( K p,uu , 0.33). AZD1390 blocks ATM-dependent DDR pathway activity and combines with radiation to induce G 2 cell cycle phase accumulation, micronuclei, and apoptosis. AZD1390 radiosensitizes glioma and lung cancer cell lines, with p53 mutant glioma cells generally being more radiosensitized than wild type. In in vivo syngeneic and patient-derived glioma as well as orthotopic lung-brain metastatic models, AZD1390 dosed in combination with daily fractions of IR (whole-brain or stereotactic radiotherapy) significantly induced tumor regressions and increased animal survival compared to IR treatment alone. We established a pharmacokinetic-pharmacodynamic-efficacy relationship by correlating free brain concentrations, tumor phospho-ATM/phospho-Rad50 inhibition, apoptotic biomarker (cleaved caspase-3) induction, tumor regression, and survival. On the basis of the data presented here, AZD1390 is now in early clinical development for use as a radiosensitizer in central nervous system malignancies.

The brain-penetrant clinical ATM inhibitor AZD1390 radiosensitizes and improves survival of preclinical brain tumor models

PubMed Central

Wang, Yingchun; Chen, Kan; Zhang, Lingli; Zhang, Tianwei; Yang, Zhenfan; Riches, Lucy; Trinidad, Antonio G.; Pike, Kurt G.; Wilson, Joanne; Smith, Aaron; Colclough, Nicola; Johnström, Peter; Varnäs, Katarina; Takano, Akihiro; Ling, Stephanie; Orme, Jonathan; Stott, Jonathan; Barrett, Ian; Jones, Gemma; Allen, Jasmine; Kahn, Jenna; Sule, Amrita; Cronin, Anna; Chapman, Melissa; Illingworth, Ruth; Pass, Martin

2018-01-01

Poor survival rates of patients with tumors arising from or disseminating into the brain are attributed to an inability to excise all tumor tissue (if operable), a lack of blood-brain barrier (BBB) penetration of chemotherapies/targeted agents, and an intrinsic tumor radio-/chemo-resistance. Ataxia-telangiectasia mutated (ATM) protein orchestrates the cellular DNA damage response (DDR) to cytotoxic DNA double-strand breaks induced by ionizing radiation (IR). ATM genetic ablation or pharmacological inhibition results in tumor cell hypersensitivity to IR. We report the primary pharmacology of the clinical-grade, exquisitely potent (cell IC50, 0.78 nM), highly selective [>10,000-fold over kinases within the same phosphatidylinositol 3-kinase–related kinase (PIKK) family], orally bioavailable ATM inhibitor AZD1390 specifically optimized for BBB penetration confirmed in cynomolgus monkey brain positron emission tomography (PET) imaging of microdosed 11C-labeled AZD1390 (Kp,uu, 0.33). AZD1390 blocks ATM-dependent DDR pathway activity and combines with radiation to induce G2 cell cycle phase accumulation, micronuclei, and apoptosis. AZD1390 radiosensitizes glioma and lung cancer cell lines, with p53 mutant glioma cells generally being more radiosensitized than wild type. In in vivo syngeneic and patient-derived glioma as well as orthotopic lung-brain metastatic models, AZD1390 dosed in combination with daily fractions of IR (whole-brain or stereotactic radiotherapy) significantly induced tumor regressions and increased animal survival compared to IR treatment alone. We established a pharmacokinetic-pharmacodynamic-efficacy relationship by correlating free brain concentrations, tumor phospho-ATM/phospho-Rad50 inhibition, apoptotic biomarker (cleaved caspase-3) induction, tumor regression, and survival. On the basis of the data presented here, AZD1390 is now in early clinical development for use as a radiosensitizer in central nervous system malignancies. PMID:29938225

Fibroblast growth factor rescues brain endothelial cells lacking presenilin 1 from apoptotic cell death following serum starvation.

PubMed

Gama Sosa, Miguel A; De Gasperi, Rita; Hof, Patrick R; Elder, Gregory A

2016-07-22

Presenilin 1 (Psen1) is important for vascular brain development and is known to influence cellular stress responses. To understand the role of Psen1 in endothelial stress responses, we investigated the effects of serum withdrawal on wild type (wt) and Psen1-/- embryonic brain endothelial cells. Serum starvation induced apoptosis in Psen1-/- cells but did not affect wt cells. PI3K/AKT signaling was reduced in serum-starved Psen1-/- cells, and this was associated with elevated levels of phospho-p38 consistent with decreased pro-survival AKT signaling in the absence of Psen1. Fibroblast growth factor (FGF1 and FGF2), but not vascular endothelial growth factor (VEGF) rescued Psen1-/- cells from serum starvation induced apoptosis. Inhibition of FGF signaling induced apoptosis in wt cells under serum withdrawal, while blocking γ-secretase activity had no effect. In the absence of serum, FGF2 immunoreactivity was distributed diffusely in cytoplasmic and nuclear vesicles of wt and Psen1-/- cells, as levels of FGF2 in nuclear and cytosolic fractions were not significantly different. Thus, sensitivity of Psen1-/- cells to serum starvation is not due to lack of FGF synthesis but likely to effects of Psen1 on FGF release onto the cell surface and impaired activation of the PI3K/AKT survival pathway.

Final Results of Local-Regional Control and Late Toxicity of RTOG 9003: A Randomized Trial of Altered Fractionation Radiation for Locally Advanced Head and Neck Cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Beitler, Jonathan J., E-mail: jjbeitl@emory.edu; Zhang, Qiang; Fu, Karen K.

Purpose: To test whether altered radiation fractionation schemes (hyperfractionation [HFX], accelerated fractionation, continuous [AFX-C], and accelerated fractionation with split [AFX-S]) improved local-regional control (LRC) rates for patients with squamous cell cancers (SCC) of the head and neck when compared with standard fractionation (SFX) of 70 Gy. Methods and Materials: Patients with stage III or IV (or stage II base of tongue) SCC (n=1076) were randomized to 4 treatment arms: (1) SFX, 70 Gy/35 daily fractions/7 weeks; (2) HFX, 81.6 Gy/68 twice-daily fractions/7 weeks; (3) AFX-S, 67.2 Gy/42 fractions/6 weeks with a 2-week rest after 38.4 Gy; and (4) AFX-C, 72 Gy/42 fractions/6 weeks. The 3 experimental arms were to bemore » compared with SFX. Results: With patients censored for LRC at 5 years, only the comparison of HFX with SFX was significantly different: HFX, hazard ratio (HR) 0.79 (95% confidence interval 0.62-1.00), P=.05; AFX-C, 0.82 (95% confidence interval 0.65-1.05), P=.11. With patients censored at 5 years, HFX improved overall survival (HR 0.81, P=.05). Prevalence of any grade 3, 4, or 5 toxicity at 5 years; any feeding tube use after 180 days; or feeding tube use at 1 year did not differ significantly when the experimental arms were compared with SFX. When 7-week treatments were compared with 6-week treatments, accelerated fractionation appeared to increase grade 3, 4 or 5 toxicity at 5 years (P=.06). When the worst toxicity per patient was considered by treatment only, the AFX-C arm seemed to trend worse than the SFX arm when grade 0-2 was compared with grade 3-5 toxicity (P=.09). Conclusions: At 5 years, only HFX improved LRC and overall survival for patients with locally advanced SCC without increasing late toxicity.« less

Cellular, physiological, and molecular adaptive responses of Erwinia amylovora to starvation.

PubMed

Santander, Ricardo D; Oliver, James D; Biosca, Elena G

2014-05-01

Erwinia amylovora causes fire blight, a destructive disease of rosaceous plants distributed worldwide. This bacterium is a nonobligate pathogen able to survive outside the host under starvation conditions, allowing its spread by various means such as rainwater. We studied E. amylovora responses to starvation using water microcosms to mimic natural oligotrophy. Initially, survivability under optimal (28 °C) and suboptimal (20 °C) growth temperatures was compared. Starvation induced a loss of culturability much more pronounced at 28 °C than at 20 °C. Natural water microcosms at 20 °C were then used to characterize cellular, physiological, and molecular starvation responses of E. amylovora. Challenged cells developed starvation-survival and viable but nonculturable responses, reduced their size, acquired rounded shapes and developed surface vesicles. Starved cells lost motility in a few days, but a fraction retained flagella. The expression of genes related to starvation, oxidative stress, motility, pathogenicity, and virulence was detected during the entire experimental period with different regulation patterns observed during the first 24 h. Further, starved cells remained as virulent as nonstressed cells. Overall, these results provide new knowledge on the biology of E. amylovora under conditions prevailing in nature, which could contribute to a better understanding of the life cycle of this pathogen. © 2014 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

Oncogenic transformation through the cell cycle and the LET dependent inverse dose rate effect

NASA Technical Reports Server (NTRS)

Geard, C. R.; Miller, R. C.; Brenner, D. J.; Hall, E. J.; Wachholz, B. W. (Principal Investigator)

1994-01-01

Synchronised populations of mouse C3H/10T-1/2 cells were obtained by a stringent mitotic dislodgment procedure. Mitotic cells rapidly attach and progress sequentially through the cell cycle. Irradiation (3 Gy of X rays) was carried out at intervals from 0 to 18 h after initiating cell cycle progression of the mitotic cells. Oncogenic transformation was enhanced 10-fold over cells irradiated soon after replating (G1 and S phases) for cells in a near 2 h period corresponding to cells in G2 phase but not in mitosis. The cell surviving fraction had a 2-1/2-fold variation with resistant peaks corresponding to the late G1 and late S phases. These findings provide experimental support for the hypothesis initiated by Rossi and Kellerer and developed by Brenner and Hall to explain the LET dependent inverse dose rate effect for oncogenic transformation.

Intra-myocardial injection of both growth factors and heart derived Sca-1+/CD31- cells attenuates post-MI LV remodeling more than does cell transplantation alone: neither intervention enhances functionally significant cardiomyocyte regeneration.

PubMed

Wang, Xiaohong; Li, Qinglu; Hu, Qingsong; Suntharalingam, Piradeep; From, Arthur H L; Zhang, Jianyi

2014-01-01

Insulin-like growth factor 1 (IGF-1) and hepatocyte growth factor (HGF) are two potent cell survival and regenerative factors in response to myocardial injury (MI). We hypothesized that simultaneous delivery of IGF+HGF combined with Sca-1+/CD31- cells would improve the outcome of transplantation therapy in response to the altered hostile microenvironment post MI. One million adenovirus nuclear LacZ-labeled Sca-1+/CD31- cells were injected into the peri-infarction area after left anterior descending coronary artery (LAD) ligation in mice. Recombinant mouse IGF-1+HGF was added to the cell suspension prior to the injection. The left ventricular (LV) function was assessed by echocardiography 4 weeks after the transplantation. The cell engraftment, differentiation and cardiomyocyte regeneration were evaluated by histological analysis. Sca-1+/CD31- cells formed viable grafts and improved LV ejection fraction (EF) (Control, 54.5+/-2.4; MI, 17.6+/-3.1; Cell, 28.2+/-4.2, n = 9, P<0.01). IGF+HGF significantly enhanced the benefits of cell transplantation as evidenced by increased EF (38.8+/-2.2; n = 9, P<0.01) and attenuated adverse structural remodeling. Furthermore, IGF+HGF supplementation increased the cell engraftment rate, promoted the transplanted cell survival, enhanced angiogenesis, and minimally stimulated endogenous cardiomyocyte regeneration in vivo. The in vitro experiments showed that IGF+HGF treatment stimulated Sca-1+/CD31- cell proliferation and inhibited serum free medium induced apoptosis. Supperarray profiling of Sca-1+/CD31- cells revealed that Sca-1+/CD31- cells highly expressed various trophic factor mRNAs and IGF+HGF treatment altered the mRNAs expression patterns of these cells. These data indicate that IGF-1+HGF could serve as an adjuvant to cell transplantation for myocardial repair by stimulating donor cell and endogenous cardiac stem cell survival, regeneration and promoting angiogenesis.

Improved human islet preparations using Glucocorticoid and Exendin-4

PubMed Central

Miki, Atsushi.; Ricordi, Camillo.; Yamamoto, Toshiyuki.; Sakuma, Yasunaru.; Misawa, Ryosuke.; Mita, Atsuyoshi.; Inverardi, Luca.; Alejandro, Rodolfo; Ichii, Hirohito.

2014-01-01

Objectives The effects of Glucocorticoid during culture on human islet cells have been controversial. Exendin-4 (EX) enhances the insulin secretion and significantly improves clinical outcomes in islet cell transplantation. In this study, we examined the effects of Glucocorticoids and exendin-4 on human islet cells during pre-transplant culture. Methods Methylprednisolone (MP) and/or EX were added to the standard culture medium for clinical islet cell transplantation. Islets were cultured for 24 hours with three different conditions (Control: no additives, MP alone, MP+EX). Beta cell fractional viability, cellular composition, multiple cytokine/chemokine production, multiple phosphorylation proteins and glucose induced insulin secretion were evaluated. Results Viable beta cell survival in MP and MP+EX group was significantly higher than in the control group. EX prevented MP induced reduction of insulin secretion. MP supplementation to the culture medium decreased cytokine and chemokine production. Moreover, Erk1/2 phosphorylation was significantly increased by MP and MP+EX. Conclusions Glucocorticoid supplementation into culture media significantly decreased the cytokine/chemokine production and increased the Erk1/2 phosphorylation, resulting in the improvement of human beta cell survival. In addition, EX maintained the insulin secretion suppressed by MP. The supplementation of MP and EX together could be a useful strategy to create suitable human islets for transplantation. PMID:25036907

Ionizing radiation, ion transports, and radioresistance of cancer cells

PubMed Central

Huber, Stephan M.; Butz, Lena; Stegen, Benjamin; Klumpp, Dominik; Braun, Norbert; Ruth, Peter; Eckert, Franziska

2013-01-01

The standard treatment of many tumor entities comprises fractionated radiation therapy which applies ionizing radiation to the tumor-bearing target volume. Ionizing radiation causes double-strand breaks in the DNA backbone that result in cell death if the number of DNA double-strand breaks exceeds the DNA repair capacity of the tumor cell. Ionizing radiation reportedly does not only act on the DNA in the nucleus but also on the plasma membrane. In particular, ionizing radiation-induced modifications of ion channels and transporters have been reported. Importantly, these altered transports seem to contribute to the survival of the irradiated tumor cells. The present review article summarizes our current knowledge on the underlying mechanisms and introduces strategies to radiosensitize tumor cells by targeting plasma membrane ion transports. PMID:23966948

DNA damage induction and/or repair as mammalian cell biomarker for the prediction of cellular radiation response

NASA Astrophysics Data System (ADS)

Baumstark-Khan, C.

DNA damage and its repair processes are key factors in cancer induction and also in the treatment of malignancies. Cancer prevention during extended space missions becomes a topic of great importance for space radiobiology. The knowledge of individual responsiveness would allow the protection strategy to be tailored optimally in each case. Radiobiological analysis of cultured cells derived from tissue explants from individuals has shown that measurement of the surviving fraction after 2 Gy (SF2) may be used to predict the individual responsiveness. However, clonogenic assays are timeconsuming, thus alternative assays for the determination of radiore-sponse are being sought. For that reason CHO cell strains having different repair capacities were used for examining whether DNA strand break repair is a suitable experimental design to allow predictive statements. Cellular survival (CFA assay) and DNA strand breaks (total DNA strand breaks: FADU technique; DSBs: non-denaturing elution) were determined in parallel immediately after irradiation as well as after a 24 hour recovery period according to dose. There were no correlations between the dose-response curves of the initial level of DNA strand breaks and parameters that describe clonogenic survival curves (SF2). A good correlation exists between intrinsic cellular radioresistance and the extent of residual DNA strand breaks.

Apoptosis-Resistant Cardiac Progenitor Cells Modified With Apurinic/Apyrimidinic Endonuclease/Redox Factor 1 Gene Overexpression Regulate Cardiac Repair After Myocardial Infarction.

PubMed

Aonuma, Tatsuya; Takehara, Naofumi; Maruyama, Keisuke; Kabara, Maki; Matsuki, Motoki; Yamauchi, Atsushi; Kawabe, Jun-Ichi; Hasebe, Naoyuki

2016-08-01

: Overcoming the insufficient survival of cell grafts is an essential objective in cell-based therapy. Apurinic/apyrimidinic endonuclease/redox factor 1 (APE1) promotes cell survival and may enhance the therapeutic effect of engrafted cells. The aim of this study is to determine whether APE1 overexpression in cardiac progenitor cells (CPCs) could ameliorate the efficiency of cell-based therapy. CPCs isolated from 8- to 10-week-old C57BL/6 mouse hearts were infected with retrovirus harboring APE1-DsRed (APE1-CPC) or a DsRed control (control-CPC). Oxidative stress-induced apoptosis was then assessed in APE1-CPCs, control-CPCs, and neonatal rat ventricular myocytes (NRVMs) cocultured with these CPCs. This analysis revealed that APE1 overexpression inhibited CPC apoptosis with activation of transforming growth factor β-activated kinase 1 (TAK1) and nuclear factor (NF)-κB. In the coculture model, NRVM apoptosis was inhibited to a greater extent in the presence of APE1-CPCs compared with control-CPCs. Moreover, the number of surviving DsRed-positive CPC grafts was significantly higher 7 days after the transplant of APE1-CPCs into a mouse myocardial infarction model, and the left ventricular ejection fraction showed greater improvement with attenuation of fibrosis 28 days after the transplant of APE1-CPCs compared with control-CPCs. Additionally, fewer inflammatory macrophages and a higher percentage of cardiac α-sarcomeric actinin-positive CPC-grafts were observed in mice injected with APE1-CPCs compared with control-CPCs after 7 days. In conclusion, antiapoptotic APE1-CPC graft, which increased TAK1-NF-κB pathway activation, survived effectively in the ischemic heart, restored cardiac function, and reduced cardiac inflammation and fibrosis. APE1 overexpression in CPCs may serve as a novel strategy to improve cardiac cell therapy. Improving the survival of cell grafts is essential to maximize the efficacy of cell therapy. The authors investigated the role of APE1 in CPCs under ischemic conditions and evaluated the therapeutic efficacy of transplanted APE1-overexpressing CPCs in a mouse model of myocardial infarction. APE1 hindered apoptosis in CPC grafts subjected to oxidative stress caused in part by increased TAK1-NF-κB pathway activation. Furthermore, APE1-CPC grafts that effectively survived in the ischemic heart restored cardiac function and attenuated fibrosis through pleiotropic mechanisms that remain to be characterized. These findings suggest that APE1 overexpression in CPCs may be a novel strategy to reinforce cardiac cell therapy. ©AlphaMed Press.

Growth-suppressing and algicidal properties of an extract from Arundo donax, an invasive riparian plant, against Prymnesium parvum, an invasive harmful alga.

PubMed

Patiño, Reynaldo; Rashel, Rakib H; Rubio, Amede; Longing, Scott

2018-01-01

This study examined the ability of acidic and neutral/alkaline fractions of a methanolic extract from giant reed (Arundo donax) and of two of its constituents, gramine and skatole, to inhibit growth of the ichthyotoxic golden alga (Prymnesium parvum) in batch culture. For this study, growth suppression was defined as inhibition of maximum cell density, algicidal activity as early occurrence of negative growth, and algistatic activity as lack of net growth. The acidic fraction did not affect algal growth. The neutral/alkaline fraction showed growth-suppressing and algicidal activities but no signs of algistatic activity - namely, cells in cultures surviving a partial-algicidal exposure concentration (causing transient negative growth) were later able to initiate positive growth but at higher concentrations, algicidal activity was full and irreversible. Gramine suppressed growth more effectively than skatole and at the highest concentration tested, gramine also showed partial-algicidal and algistatic activity. While the partial-algicidal activities of the neutral/alkaline fraction and of gramine were short-lived (≤6days) and thus may share similar mechanisms, algistatic activity was unique to gramine and persisted for >3 weeks. Given gramine's reported concentration in the neutral/alkaline fraction, its corresponding level of algicidal activity is much lower than the fraction's suggesting the latter contains additional potent algicides. Inhibition of maximum cell density by all test compounds was associated with reductions in exponential growth rate, and in the case of the neutral/alkaline fraction and gramine also reductions in early (pre-exponential) growth. These results indicate that giant reed is a potential source of natural products to control golden alga blooms. Giant reed is an invasive species in North America, thus also providing incentive for research into strategies to couple management efforts for both species. Published by Elsevier B.V.

Stereotactic Body Radiation Therapy and the Influence of Chemotherapy on Overall Survival for Large (≥5 Centimeter) Non-Small Cell Lung Cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Verma, Vivek; McMillan, Matthew T.; Grover, Surbhi

2017-01-01

Purpose: Stereotactic body radiation therapy (SBRT) for ≥5 cm lesions is poorly defined, largely owing to the low sample sizes in existing studies. The present analysis examined the SBRT outcomes and assessed the effect of chemotherapy in this population. Methods and Materials: The National Cancer Data Base was queried for primary non-small cell lung cancer ≥5 cm treated with SBRT (≤10 fractions). Patient, tumor, and treatment parameters were extracted. The primary outcome was overall survival (OS). Statistical methods involved Kaplan-Meier analysis and multivariable Cox proportional hazards modeling. Results: From 2004 to 2012, data from 201 patients were analyzed. The median follow-upmore » was 41.1 months. The median tumor size was 5.5 cm (interquartile range 5.0-6.0), with cT2a, cT2b, and cT3 disease in 24.9%, 53.2%, and 21.9%, respectively. The median total SBRT dose and fractionation was 50 Gy in 4 fractions, and 92.5% of the patients underwent SBRT with ≤5 fractions. The median OS was 25.1 months. Of the 201 patients, 15% received chemotherapy. The receipt of chemotherapy was associated with longer OS (median 30.6 vs 23.4 months; P=.027). On multivariable analysis, worse OS was seen with increasing age (hazard ratio [HR] 1.03; P=.012), poorly differentiated tumors (HR 2.06; P=.049), and T3 classification (HR 2.13; P=.005). On multivariable analysis, chemotherapy remained independently associated with improved OS (HR 0.57; P=.039). Conclusions: SBRT has utility in the setting of tumors ≥5 cm, with chemotherapy associated with improved OS in this subset. These hypothesis-generating data now raise the necessity of performing prospective analyses to determine whether chemotherapy confers outcome benefits after SBRT.« less

Xiphinema americanum as Affected by Soil Organic Matter and Porosity.

PubMed

Ponchillia, P E

1972-07-01

The effects of four soil types, soil porosity, particle size, and organic matter were tested on survival and migration of Xiphinema americanum. Survival and migration were significantly greater in silt loam than in clay loam and silty clay soils. Nematode numbers were significantly greater in softs planted with soybeans than in fallow softs. Nematode survival was greatest at the higher of two pore space levels in four softs. Migration of X. americanum through soft particle size fractions of 75-150, 150-250, 250-500, 500-700, and 700-1,000 mu was significantly greater in the middle three fractions, with the least occurring in the smallest fraction. Additions of muck to silt loam and loamy sand soils resulted in reductions in survival and migration of the nematode. The fulvic acid fraction of muck, extracted with sodium hydroxide, had a deleterious effect on nematode activity. I conclude that soils with small amounts of air-filled pore space, extremes in pore size, or high organic matter content are deleterious to the migration and survival of X. americanum, and that a naturally occurring toxin affecting this species may be present in native soft organic matter.

Multi-Institutional Experience of Stereotactic Ablative Radiation Therapy for Stage I Small Cell Lung Cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Verma, Vivek; Simone, Charles B.; Allen, Pamela K.

Purpose: For inoperable stage I (T1-T2N0) small cell lung cancer (SCLC), national guidelines recommend chemotherapy with or without conventionally fractionated radiation therapy. The present multi-institutional cohort study investigated the role of stereotactic ablative radiation therapy (SABR) for this population. Methods and Materials: The clinical and treatment characteristics, toxicities, outcomes, and patterns of failure were assessed in patients with histologically confirmed stage T1-T2N0M0 SCLC. Kaplan-Meier analysis was used to evaluate the survival outcomes. Univariate and multivariate analyses identified predictors of outcomes. Results: From 24 institutions, 76 lesions were treated in 74 patients (median follow-up 18 months). The median age and tumor sizemore » was 72 years and 2.5 cm, respectively. Chemotherapy and prophylactic cranial irradiation were delivered in 56% and 23% of cases, respectively. The median SABR dose and fractionation was 50 Gy and 5 fractions. The 1- and 3-year local control rate was 97.4% and 96.1%, respectively. The median disease-free survival (DFS) duration was 49.7 months. The DFS rate was 58.3% and 53.2% at 1 and 3 years, respectively. The median, 1-year, and 3-year disease-specific survival was 52.3 months, 84.5%, and 64.4%, respectively. The median, 1-year, and 3-year overall survival (OS) was 17.8 months, 69.9%, and 34.0% respectively. Patients receiving chemotherapy experienced an increased median DFS (61.3 vs 9.0 months; P=.02) and OS (31.4 vs 14.3 months; P=.02). The receipt of chemotherapy independently predicted better outcomes for DFS/OS on multivariate analysis (P=.01). Toxicities were uncommon; 5.2% experienced grade ≥2 pneumonitis. Post-treatment failure was most commonly distant (45.8% of recurrence), followed by nodal (25.0%) and “elsewhere lung” (20.8%). The median time to each was 5 to 7 months. Conclusions: From the findings of the largest report of SABR for stage T1-T2N0 SCLC to date, SABR (≥50 Gy) with chemotherapy should be considered a standard option.« less

Hyperfractionated accelerated radiotherapy with concomitant integrated boost of 70-75 Gy in 5 weeks for advanced head and neck cancer. A phase I dose escalation study.

PubMed

Cvek, J; Kubes, J; Skacelikova, E; Otahal, B; Kominek, P; Halamka, M; Feltl, D

2012-08-01

The present study was performed to evaluate the feasibility of a new, 5-week regimen of 70-75 Gy hyperfractionated accelerated radiotherapy with concomitant integrated boost (HARTCIB) for locally advanced, inoperable head and neck cancer. A total of 39 patients with very advanced, stage IV nonmetastatic head and neck squamous cell carcinoma (median gross tumor volume 72 ml) were included in this phase I dose escalation study. A total of 50 fractions intensity-modulated radiotherapy (IMRT) were administered twice daily over 5 weeks. Prescribed total dose/dose per fraction for planning target volume (PTV(tumor)) were 70 Gy in 1.4 Gy fractions, 72.5 Gy in 1.45 Gy fractions, and 75 Gy in 1.5 Gy fractions for 10, 13, and 16 patients, respectively. Uninvolved lymphatic nodes (PTV(uninvolved)) were irradiated with 55 Gy in 1.1 Gy fractions using the concomitant integrated boost. Acute toxicity was evaluated according to the RTOG/EORTC scale; the incidence of grade 3 mucositis was 51% in the oral cavity/pharynx and 0% in skin and the recovery time was ≤ 9 weeks for all patients. Late toxicity was evaluated in patients in complete remission according to the RTOG/EORTC scale. No grade 3/4 late toxicity was observed. The 1-year locoregional progression-free survival was 50% and overall survival was 55%. HARTCIB (75 Gy in 5 weeks) is feasible for patients deemed unsuitable for chemoradiation. Acute toxicity was lower than predicted from radiobiological models; duration of dysphagia and confluent mucositis were particularly short. Better conformity of radiotherapy allows the use of more intensive altered fractionation schedules compared with older studies. These results suggest that further dose escalation might be possible when highly conformal techniques (e.g., stereotactic radiotherapy) are used.

Plasma cell growth fraction using Ki-67 antigen expression identifies a subgroup of multiple myeloma patients displaying short survival within the ISS stage I.

PubMed

Gastinne, Thomas; Leleu, Xavier; Duhamel, Alain; Moreau, Anne-Sophie; Franck, Genevieve; Andrieux, Joris; Lai, Jean-Luc; Coiteux, Valerie; Yakoub-Agha, Ibrahim; Bauters, Francis; Harousseau, Jean-Luc; Zandecki, Marc; Facon, Thierry

2007-10-01

The current most powerful prognostic model in Multiple Myeloma (MM) combines beta-2 microglobulin (b2m) with albumin, corresponding to the International Staging System (ISS). However, the prognosis of patients within the ISS stage I (high albumin and low b2m) may vary. Ki-67 is a nuclear protein associated with cell proliferation. We retrospectively evaluated the percentage of bone marrow plasma cells expressing Ki-67 antigen (Ki-67 index) in a series of 174 untreated MM patients at diagnosis. Median survival was 51, 41 and 20 months respectively, and median Ki-67 index was 3.0%, 6.1% and 6.5% in ISS stages I, II, and III respectively. Independently of ISS, Ki-67 index > or =4% was highly predictive of adverse prognosis. Ki-67 index correlated with markers of intrinsic malignancy and with markers of tumour burden. Within ISS stage I, median survival was of 31 months (RR of death 2.65) in patients with Ki-67 index > or =4%. Eventually, the combination of Ki-67 with b2m produced an efficient prognostic model, which appeared most effective in our series when compared with b2m and KI-67 with chromosome 13 deletion models. In this series, we demonstrated that a proliferation marker provides clear-cut additional survival prognostic information to b2m into the ISS model.

CD1d expression on chronic lymphocytic leukemia B cells affects disease progression and induces T cell skewing in CD8 positive and CD4CD8 double negative T cells.

PubMed

Zaborsky, Nadja; Gassner, Franz Josef; Asslaber, Daniela; Reinthaler, Petra; Denk, Ursula; Flenady, Sabine; Hofbauer, Josefina Piñón; Danner, Barbara; Rebhandl, Stefan; Harrer, Andrea; Geisberger, Roland; Greil, Richard; Egle, Alexander

2016-08-02

Chronic lymphocytic leukemia develops within a complex network driven by genetic mutations and microenvironmental interactions. Among the latter a complex interplay with the immune system is established by the clone. Next to a proposed recruitment of support from T and myeloid cells, potential anti-CLL immune reactions need to be subverted. By using TCL1 mice as a CLL model, we show that TCR-Vβ7+ NK1.1+ T cells are overrepresented in this disease model and constitute a main subset of peripheral CD3+ cells with biased TCR usage, showing that these cells account for a major part for T cell skewing in TCL1 mice. Moreover, we show that overrepresentation is dependent on CD1d expression in TCL1 mice, implicating that these cells belong to a NKT-like cell fraction which are restricted to antigen presented by the MHC-like surface marker CD1d. Accordingly, we observed a high fraction of CD161+ cells within overrepresented T cells in CLL patients and we found downregulation of CD1d on the surface of CLL cells, both in TCL1 mice and patients. Finally, we show that in TCL1 mice, CD1d deficiency resulted in shortened overall survival. Our results point to an interaction between CLL and CD161+ T cells that may represent a novel therapeutic target for immune modulation.

Stereotactic body radiation therapy (SBRT) improves local control and overall survival compared to conventionally fractionated radiation for stage I non-small cell lung cancer (NSCLC).

PubMed

von Reibnitz, Donata; Shaikh, Fauzia; Wu, Abraham J; Treharne, Gregory C; Dick-Godfrey, Rosalind; Foster, Amanda; Woo, Kaitlin M; Shi, Weiji; Zhang, Zhigang; Din, Shaun U; Gelblum, Daphna Y; Yorke, Ellen D; Rosenzweig, Kenneth E; Rimner, Andreas

2018-06-06

Stereotactic body radiotherapy (SBRT) has been adopted as the standard of care for inoperable early-stage non-small cell lung cancer (NSCLC), with local control rates consistently >90%. However, data directly comparing the outcomes of SBRT with those of conventionally fractionated radiotherapy (CONV) is lacking. Between 1990 and 2013, 497 patients (525 lesions) with early-stage NSCLC (T1-T2N0M0) were treated with CONV (n = 127) or SBRT (n = 398). In this retrospective analysis, five endpoints were compared, with and without adjusting for clinical and dosimetric factors. Competing risks analysis was performed to estimate and compare the cumulative incidence of local failure (LF), nodal failure (NF), distant failure (DF) and disease progression. Overall survival (OS) was estimated by the Kaplan-Meier method and compared by the Cox regression model. Propensity score (PS) matched analysis was performed based on seven patient and clinical variables: age, gender, Karnofsky performance status (KPS), histology, T stage, biologically equivalent dose (BED), and history of smoking. The median dose delivered for CONV was 75.6 Gy in 1.8-2.0 Gy fractions (range 60-90 Gy; median BED = 89.20 Gy) and for SBRT 48 Gy in four fractions (45-60 Gy in three to five fractions; median BED = 105.60 Gy). Median follow-up was 24.4 months, and 3-year LF rates were 34.1% with CONV and 13.6% with SBRT (p < .001). Three-year OS rates were 38.9 and 53.1%, respectively (p = .018). PS matching showed a significant improvement of OS (p = .0497) for SBRT. T stage was the only variable correlating with all five endpoints. SBRT compared to CONV is associated with improved LF rates and OS. Our data supports the continued use and expansion of SBRT as the standard of care treatment for inoperable early-stage NSCLC.

Essential Roles for Caenorhabditis elegans Lamin Gene in Nuclear Organization, Cell Cycle Progression, and Spatial Organization of Nuclear Pore Complexes

PubMed Central

Liu, Jun; Ben-Shahar, Tom Rolef; Riemer, Dieter; Treinin, Millet; Spann, Perah; Weber, Klaus; Fire, Andrew; Gruenbaum, Yosef

2000-01-01

Caenorhabditis elegans has a single lamin gene, designated lmn-1 (previously termed CeLam-1). Antibodies raised against the lmn-1 product (Ce-lamin) detected a 64-kDa nuclear envelope protein. Ce-lamin was detected in the nuclear periphery of all cells except sperm and was found in the nuclear interior in embryonic cells and in a fraction of adult cells. Reductions in the amount of Ce-lamin protein produce embryonic lethality. Although the majority of affected embryos survive to produce several hundred nuclei, defects can be detected as early as the first nuclear divisions. Abnormalities include rapid changes in nuclear morphology during interphase, loss of chromosomes, unequal separation of chromosomes into daughter nuclei, abnormal condensation of chromatin, an increase in DNA content, and abnormal distribution of nuclear pore complexes (NPCs). Under conditions of incomplete RNA interference, a fraction of embryos escaped embryonic arrest and continue to develop through larval life. These animals exhibit additional phenotypes including sterility and defective segregation of chromosomes in germ cells. Our observations show that lmn-1 is an essential gene in C. elegans, and that the nuclear lamins are involved in chromatin organization, cell cycle progression, chromosome segregation, and correct spacing of NPCs. PMID:11071918

The use of primary rat hepatocytes to achieve metabolic activation of promutagens in the Chinese hamster ovary/hypoxanthine-guanine phosphoribosyl transferase mutational assay.

PubMed

Bermudez, E; Couch, D B; Tillery, D

1982-01-01

A method is described in which primary rat hepatocytes have been cocultured with Chinese hamster ovary (CHO) cells to provide metabolic activation of promutagens in the Chinese hamster ovary/hypoxanthine-guanine phosphoribosyl transferase (CHO/HGPRT) mutational assay. Single cell hepatocyte suspensions were prepared from male Fischer-344 rats using the in situ collagenase perfusion technique. Hepatocytes were allowed to attach for 1.5 hours in tissue culture dishes containing an approximately equal number of CHO cells in log growth. The cocultures were exposed to promutagens for up to 20 hours in serum-free medium. The survival and 6-thioguanine-resistant fraction of treated CHO cells were then determined as in the standard CHO/HGPRT assay. Aflatoxin B1 (AFB1) 7,12-dimethylbenz(a)anthracene (DMBA) and benzo(a)pyrene (B(A)P) were found to produce increases in the mutant fractions of treated CHO cells as a function of concentration. The time required for optimum expression of the mutant phenotype following exposure to DMBA and AFB1 was approximately 8 days. Primary cell-mediated mutagenesis may be useful in elucidating metabolic pathways important in the production and detoxification of genotoxic products in vivo.

Methodology to Estimate the Longitudinal Average Attributable Fraction of Guideline-recommended Medications for Death in Older Adults With Multiple Chronic Conditions

PubMed Central

Zhan, Yilei; Cohen, Andrew B.; Tinetti, Mary E.; Trentalange, Mark; McAvay, Gail

2016-01-01

Background: Persons with multiple chronic conditions receive multiple guideline-recommended medications to improve outcomes such as mortality. Our objective was to estimate the longitudinal average attributable fraction for 3-year survival of medications for cardiovascular conditions in persons with multiple chronic conditions and to determine whether heterogeneity occurred by age. Methods: Medicare Current Beneficiary Survey participants (N = 8,578) with two or more chronic conditions, enrolled from 2005 to 2009 with follow-up through 2011, were analyzed. We calculated the longitudinal extension of the average attributable fraction for oral medications (beta blockers, renin–angiotensin system blockers, and thiazide diuretics) indicated for cardiovascular conditions (atrial fibrillation, coronary artery disease, heart failure, and hypertension), on survival adjusted for 18 participant characteristics. Models stratified by age (≤80 and >80 years) were analyzed to determine heterogeneity of both cardiovascular conditions and medications. Results: Heart failure had the greatest average attributable fraction (39%) for mortality. The fractional contributions of beta blockers, renin–angiotensin system blockers, and thiazides to improve survival were 10.4%, 9.3%, and 7.2% respectively. In age-stratified models, of these medications thiazides had a significant contribution to survival only for those aged 80 years or younger. The effects of the remaining medications were similar in both age strata. Conclusions: Most cardiovascular medications were attributed independently to survival. The two cardiovascular conditions contributing independently to death were heart failure and atrial fibrillation. The medication effects were similar by age except for thiazides that had a significant contribution to survival in persons younger than 80 years. PMID:26748093

Validation of 64Cu-ATSM damaging DNA via high-LET Auger electron emission

PubMed Central

McMillan, Dayton D.; Maeda, Junko; Bell, Justin J.; Genet, Matthew D.; Phoonswadi, Garrett; Mann, Kelly A.; Kraft, Susan L.; Kitamura, Hisashi; Fujimori, Akira; Yoshii, Yukie; Furukawa, Takako; Fujibayashi, Yasuhisa; Kato, Takamitsu A.

2015-01-01

Radioactive copper (II) (diacetyl-bis N4-methylthiosemicarbazone) (Cu-ATSM) isotopes were originally developed for the imaging of hypoxia in tumors. Because the decay of a 64Cu atom is emitting not only positrons but also Auger electrons, this radionuclide has great potential as a theranostic agent. However, the success of 64Cu-ATSM internal radiation therapy would depend on the contribution of Auger electrons to tumor cell killing. Therefore, we designed a cell culture system to define the contributions to cell death from Auger electrons to support or refute our hypothesis that the majority of cell death from 64Cu-ATSM is a result of high-LET Auger electrons and not positrons or other low-LET radiation. Chinese hamster ovary (CHO) wild type and DNA repair–deficient xrs5 cells were exposed to 64Cu-ATSM during hypoxic conditions. Surviving fractions were compared with those surviving gamma-radiation, low-LET hadron radiation, and high-LET heavy ion exposure. The ratio of the D10 values (doses required to achieve 10% cell survival) between CHO wild type and xrs5 cells suggested that 64Cu-ATSM toxicity is similar to that of high-LET Carbon ion radiation (70 keV/μm). γH2AX foci assays confirmed DNA double-strand breaks and cluster damage by high-LET Auger electrons from 64Cu decay, and complex types of chromosomal aberrations typical of high-LET radiation were observed after 64Cu-ATSM exposure. The majority of cell death was caused by high-LET radiation. This work provides strong evidence that 64Cu-ATSM damages DNA via high-LET Auger electrons, supporting further study and consideration of 64Cu-ATSM as a cancer treatment modality for hypoxic tumors. PMID:26251463

Dendritic Cell-Based Vaccines that Utilize Myeloid Rather than Plasmacytoid Cells Offer a Superior Survival Advantage in Malignant Glioma.

PubMed

Dey, Mahua; Chang, Alan L; Miska, Jason; Wainwright, Derek A; Ahmed, Atique U; Balyasnikova, Irina V; Pytel, Peter; Han, Yu; Tobias, Alex; Zhang, Lingjiao; Qiao, Jian; Lesniak, Maciej S

2015-07-01

Dendritic cells (DCs) are professional APCs that are traditionally divided into two distinct subsets, myeloid DC (mDCs) and plasmacytoid DC (pDCs). pDCs are known for their ability to secrete large amounts of IFN-α. Apart from IFN-α production, pDCs can also process Ag and induce T cell immunity or tolerance. In several solid tumors, pDCs have been shown to play a critical role in promoting tumor immunosuppression. We investigated the role of pDCs in the process of glioma progression in the syngeneic murine model of glioma. We show that glioma-infiltrating pDCs are the major APC in glioma and are deficient in IFN-α secretion (p < 0.05). pDC depletion leads to increased survival of the mice bearing intracranial tumor by decreasing the number of regulatory T cells (Tregs) and by decreasing the suppressive capabilities of Tregs. We subsequently compared the ability of mDCs and pDCs to generate effective antiglioma immunity in a GL261-OVA mouse model of glioma. Our data suggest that mature pDCs and mDCs isolated from naive mice can be effectively activated and loaded with SIINFEKL Ag in vitro. Upon intradermal injection in the hindleg, a fraction of both types of DCs migrate to the brain and lymph nodes. Compared to mice vaccinated with pDC or control mice, mice vaccinated with mDCs generate a robust Th1 type immune response, characterized by high frequency of CD4(+)T-bet(+) T cells and CD8(+)SIINFEKEL(+) T cells. This robust antitumor T cell response results in tumor eradication and long-term survival in 60% of the animals (p < 0.001). Copyright © 2015 by The American Association of Immunologists, Inc.

Monte Carlo dose distribution calculation at nuclear level for Auger-emitting radionuclide energies.

PubMed

Di Maria, S; Belchior, A; Romanets, Y; Paulo, A; Vaz, P

2018-05-01

The distribution of radiopharmaceuticals in tumor cells represents a fundamental aspect for a successful molecular targeted radiotherapy. It was largely demonstrated at microscopic level that only a fraction of cells in tumoral tissues incorporate the radiolabel. In addition, the distribution of the radionuclides at sub-cellular level, namely inside each nucleus, should also be investigated for accurate dosimetry estimation. The most used method to perform cellular dosimetry is the MIRD one, where S-values are able to estimate cellular absorbed doses for several electron energies, nucleus diameters, and considering homogeneous source distributions. However the radionuclide distribution inside nuclei can be also highly non-homogeneous. The aim of this study is to show in what extent a non-accurate cellular dosimetry could lead to misinterpretations of surviving cell fraction vs dose relationship; in this context, a dosimetric case study with 99m Tc is also presented. The state-of-art MCNP6 Monte Carlo simulation was used in order to model cell structures both in MIRD geometry (MG) and MIRD modified geometries (MMG), where also entire mitotic chromosome volumes were considered (each structure was modeled as liquid water material). In order to simulate a wide energy range of Auger emitting radionuclides, four mono energetic electron emissions were considered, namely 213eV, 6keV, 11keV and 20keV. A dosimetric calculation for 99m Tc undergoing inhomogeneous nuclear internalization was also performed. After a successful validation step between MIRD and our computed S-values for three Auger-emitting radionuclides ( 99m Tc, 125 I and 64 Cu), absorbed dose results showed that the standard MG could differ from the MMG from one to three orders of magnitude. These results were also confirmed by considering the 99m Tc spectrum emission (Auger and internal conversion electrons). Moreover, considering an inhomogeneous radionuclide distribution, the average electron energy that maximizes the absorbed dose was found to be different for MG and MMG. The modeling of realistic radionuclide localization inside cells, including a inhomogeneous nuclear distribution, revealed that i) a strong bias in surviving cell fraction vs dose relationships (taking to different radiobiological models) can arise; ii) the alternative models might contribute to a more accurate prediction of the radiobiological effects inherent to more specific molecular targeted radiotherapy strategies. Copyright © 2018 Elsevier Ltd. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, B; Cvetkovic, D; Chen, L

Purpose: Recently it has been reported that Bosutinib, a clinical kinase inhibitor, can enhance the tumor cell chemosensitivity by overriding DNA damage checkpoints. However, to the best of our knowledge, there is no report on its effect on cell radiosensitivity in the literature. The objective of the present study is to determine whether Bosutinib has the potential to be used as a radiosensitizer for various cancer cell lines. Methods: In this study, we tested 4 cell lines derived from human prostate (LNCaP, PC-3, DU-145) and colon (HT-29) cancers. The cells were seeded into 12-well plates 24 hours prior to themore » radiation treatments. For each cell line, we designed 4 study groups, namely, the control, Bosutinib, radiotherapy, and radiotherapy+Bosutinib groups. We used 6 MV photon beams from a Siemens Artiste accelerator to deliver 2 Gy dose in one fraction to the cells in the radiotherapy and radiotherapy+Bosutinib groups. Immediately after irradiation, the cells in the radiotherapy+Bosutinib group were treated with Bosutinib (1µM) for 3 hours. The cell survival was evaluated through clonogenic assays. Results: The cell survival rates of the LNCaP, PC-3, DU-145, and HT-29 cells were found to be 21%, 92%, 76%, and 93% for the radiotherapy group; 21%, 69%, 67%, and 81% for the radiotherapy+Bosutinib group; and 103%, 107%, 86%, and 102% for the Bosutinib group, respectively. Although synergetic cell killing was not seen for the LNCaP and DU-145 cell lines in this study, the cell survival data from the clonogenic assay indicated that Bosutinib could enhance the sensitivity of PC-3 and HT-29 cells to radiation treatment. Conclusion: Our preliminary results demonstrated the possibility of Bosutinib as a radiosensitizer for certain prostate and colon cancers, which are resistant to radiotherapy. Further studies are warranted to quantify the radiosensitizing effect of Bosutinib.« less

Single-Fraction Versus 5-Fraction Radiation Therapy for Metastatic Epidural Spinal Cord Compression in Patients With Limited Survival Prognoses: Results of a Matched-Pair Analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rades, Dirk, E-mail: Rades.Dirk@gmx.net; Huttenlocher, Stefan; Šegedin, Barbara

Purpose: This study compared single-fraction to multi-fraction short-course radiation therapy (RT) for symptomatic metastatic epidural spinal cord compression (MESCC) in patients with limited survival prognosis. Methods and Materials: A total of 121 patients who received 8 Gy × 1 fraction were matched (1:1) to 121 patients treated with 4 Gy × 5 fractions for 10 factors including age, sex, performance status, primary tumor type, number of involved vertebrae, other bone metastases, visceral metastases, interval between tumor diagnosis and MESCC, pre-RT ambulatory status, and time developing motor deficits prior to RT. Endpoints included in-field repeated RT (reRT) for MESCC, overall survival (OS), and impact of RT onmore » motor function. Univariate analyses were performed with the Kaplan-Meier method and log-rank test for in-field reRT for MESCC and OS and with the ordered-logit model for effect of RT on motor function. Results: Doses of 8 Gy × 1 fraction and 4 Gy × 5 fractions were not significantly different with respect to the need for in-field reRT for MESCC (P=.11) at 6 months (18% vs 9%, respectively) and 12 months (30% vs 22%, respectively). The RT regimen also had no significant impact on OS (P=.65) and post-RT motor function (P=.21). OS rates at 6 and 12 months were 24% and 9%, respectively, after 8 Gy × 1 fraction versus 25% and 13%, respectively, after 4 Gy × 5 fractions. Improvement of motor function was observed in 17% of patients after 8 Gy × 1 fraction and 23% after 4 Gy × 5 fractions, respectively. Conclusions: There were no significant differences with respect to need for in-field reRT for MESCC, OS, and motor function by dose fractionation regimen. Thus, 8 Gy × 1 fraction may be a reasonable option for patients with survival prognosis of a few months.« less

Methylselenol, a selenium metabolite, plays common and different roles in cancerous colon HCT116 cell and noncancerous NCM460 colon cell proliferation.

PubMed

Zeng, Huawei; Briske-Anderson, Mary; Wu, Min; Moyer, Mary P

2012-01-01

Methylselenol is hypothesized to be a critical selenium metabolite for anticancer action, and differential chemopreventive effects of methylselenol on cancerous and noncancerous cells may play an important role. In this study, the submicromolar concentrations of methylselenol were generated by incubating methionase with seleno-L methionine, and colon-cancer-derived HCT-116 cells and noncancerous colon NCM460 cells were exposed to methylselenol. Methylselenol exposure inhibited cell growth and led to an increase in G1 and G2 fractions with a concomitant drop in S-phase and an induction of apoptosis in HCT116, but to a much lesser extent in NCM460 colon cells. Similarly, the examination of mitogen-activated protein kinase (MAPK) and cellular myelocytomatosis oncogene (c-Myc) signaling status revealed that methylselenol inhibited the phosphorylation of extracellular-regulated kinase1/2 and p38 mitogen-activated protein kinase and the expression of c-Myc in HCT116 cells, but also to a lesser extent in NCM460 cells. The other finding is that methylselenol inhibits sarcoma kinase phosphorylation in HCT116 cells. In contrast, methylselenol upregulated the phosphorylation of sarcoma and focal adhesion kinase survival signals in the noncancerous NCM460 cells. Collectively, methylselenol's stronger potential of inhibiting cell proliferation/survival signals in the cancerous HCT116 cells when compared with that in noncancerous NCM460 cells may partly explain the potential of methylselenol's anticancer action.

Flow-gradient patterns in severe aortic stenosis with preserved ejection fraction: clinical characteristics and predictors of survival.

PubMed

Eleid, Mackram F; Sorajja, Paul; Michelena, Hector I; Malouf, Joseph F; Scott, Christopher G; Pellikka, Patricia A

2013-10-15

Among patients with severe aortic stenosis (AS) and preserved ejection fraction, those with low gradient (LG) and reduced stroke volume may have an adverse prognosis. We investigated the prognostic impact of stroke volume using the recently proposed flow-gradient classification. We examined 1704 consecutive patients with severe AS (aortic valve area <1.0 cm(2)) and preserved ejection fraction (≥50%) using 2-dimensional and Doppler echocardiography. Patients were stratified by stroke volume index (<35 mL/m(2) [low flow, LF] versus ≥35 mL/m(2) [normal flow, NF]) and aortic gradient (<40 mm Hg [LG] versus ≥40 mm Hg [high gradient, HG]) into 4 groups: NF/HG, NF/LG, LF/HG, and LF/LG. NF/LG (n=352, 21%), was associated with favorable survival with medical management (2-year estimate, 82% versus 67% in NF/HG; P<0.0001). LF/LG severe AS (n=53, 3%) was characterized by lower ejection fraction, more prevalent atrial fibrillation and heart failure, reduced arterial compliance, and reduced survival (2-year estimate, 60% versus 82% in NF/HG; P<0.001). In multivariable analysis, the LF/LG pattern was the strongest predictor of mortality (hazard ratio, 3.26; 95% confidence interval, 1.71-6.22; P<0.001 versus NF/LG). Aortic valve replacement was associated with a 69% mortality reduction (hazard ratio, 0.31; 95% confidence interval, 0.25-0.39; P<0.0001) in LF/LG and NF/HG, with no survival benefit associated with aortic valve replacement in NF/LG and LF/HG. NF/LG severe AS with preserved ejection fraction exhibits favorable survival with medical management, and the impact of aortic valve replacement on survival was neutral. LF/LG severe AS is characterized by a high prevalence of atrial fibrillation, heart failure, and reduced survival, and aortic valve replacement was associated with improved survival. These findings have implications for the evaluation and subsequent management of AS severity.

Anti-PD-1 Blockade and Stereotactic Radiation Produce Long-Term Survival in Mice With Intracranial Gliomas

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zeng, Jing; See, Alfred P.; Phallen, Jillian

2013-06-01

Purpose: Glioblastoma multiforme (GBM) is the most common primary brain tumor in adults, and radiation is one of the main treatment modalities. However, cure rates remain low despite best available therapies. Immunotherapy is a promising modality that could work synergistically with radiation, which has been shown to increase antigen presentation and promote a proinflammatory tumor microenvironment. Programmed-death-1 (PD-1) is a surface receptor expressed on activated and exhausted T cells, which mediate T cell inhibition upon binding with its ligand PD-L1, expressed on many tumor types including human GBMs. We tested the combination of anti-PD-1 immunotherapy with stereotactic radiosurgery in amore » mouse orthotopic GBM model. Methods and Materials: We performed intracranial implantation of mouse glioma cell line GL261 transfected with luciferase into C57BL/6 mice. Mice were stratified into 4 treatment groups: (1) control; (2) radiation only; (3) anti-PD-1 antibody only; and (4) radiation plus anti-PD-1 antibody. Overall survival was quantified. The mice were killed on day 21 after implantation to assess immunologic parameters in the brain/tumor, cervical lymph nodes, and spleen. Results: Improved survival was demonstrated with combination anti-PD-1 therapy plus radiation compared with either modality alone: median survival was 25 days in the control arm, 27 days in the anti-PD-1 antibody arm, 28 days in the radiation arm, and 53 days in the radiation plus anti-PD-1 therapy arm (P<.05 by log-rank Mantle-Cox). Long-term survival was seen only in the combined treatment arm, with a fraction (15%-40%) of animals alive at day 180+ after treatment. Immunologic data on day 21 after implantation showed increased tumor infiltration by cytotoxic T cells (CD8+/interferon-γ+/tumor necrosis factor-α+) and decreased regulatory T cells (CD4+/FOXP3) in the combined treatment group compared with the single modality arms. Conclusions: The combination of PD-1 blockade and localized radiation therapy results in long-term survival in mice with orthotopic brain tumors. These studies provide strong preclinical evidence to support combination trials in patients with GBM.« less

Stage I nonsmall cell lung cancer in patients aged > or =75 years: outcomes after stereotactic radiotherapy.

PubMed

Haasbeek, Cornelis J A; Lagerwaard, Frank J; Antonisse, Marilisa E; Slotman, Ben J; Senan, Suresh

2010-01-15

The number of patients aged > or =75 years who present with a stage I nonsmall cell lung cancer (NSCLC) is increasing. Elderly patients often have significant comorbidity and may be unfit for surgery. Furthermore, surgery in the elderly is associated with increased mortality and morbidity. In this study, the authors evaluated the outcomes of stereotactic radiotherapy (SRT) in elderly patients. Since 2003, 203 tumors in 193 patients aged > or =75 years were treated using SRT (118 T1 tumors, 85 T2 tumors). The median patient age was 79 years, 80% of patients were considered medically inoperable, and 20% of patients declined surgery. The median Charlson comorbidity score was 4, and severe chronic obstructive pulmonary disease (Global Initiative for Chronic Obstructive Lung Disease Class III or greater) was present in 25% of patients. Risk-adapted SRT schemes were used with the same total dose of 60 grays in 3 fractions (33%), 5 fractions (50%), or 8 fractions (17% of patients), depending on the patient's risk for toxicity. SRT was well tolerated, and all but 1 patient completed treatment. Survival rates at 1 year and 3 years were 86% and 45%, respectively. Survival was correlated with performance score (P = .001) and pre-SRT lung function (P = .04). The actuarial local control rate at 3 years was 89%. Acute toxicity was uncommon, and late Radiation Therapy Oncology Group grade > or =3 toxicity was observed in <10% of patients. SRT achieved high local control rates with minimal toxicity in patients aged > or =75 years despite their significant medical comorbidities. These results indicated that more active diagnostic and therapeutic approaches are justified in elderly patients and that SRT should be considered and discussed as a curative treatment alternative.

Canadian Phase III Randomized Trial of Stereotactic Body Radiotherapy Versus Conventionally Hypofractionated Radiotherapy for Stage I, Medically Inoperable Non-Small-Cell Lung Cancer - Rationale and Protocol Design for the Ontario Clinical Oncology Group (OCOG)-LUSTRE Trial.

PubMed

Swaminath, Anand; Wierzbicki, Marcin; Parpia, Sameer; Wright, James R; Tsakiridis, Theodoros K; Okawara, Gordon S; Kundapur, Vijayananda; Bujold, Alexis; Ahmed, Naseer; Hirmiz, Khalid; Kurien, Elizabeth; Filion, Edith; Gabos, Zsolt; Faria, Sergio; Louie, Alexander V; Owen, Timothy; Wai, Elaine; Ramchandar, Kevin; Chan, Elisa K; Julian, Jim; Cline, Kathryn; Whelan, Timothy J

2017-03-01

We describe a Canadian phase III randomized controlled trial of stereotactic body radiotherapy (SBRT) versus conventionally hypofractionated radiotherapy (CRT) for the treatment of stage I medically inoperable non-small-cell lung cancer (OCOG-LUSTRE Trial). Eligible patients are randomized in a 2:1 fashion to either SBRT (48 Gy in 4 fractions for peripherally located lesions; 60 Gy in 8 fractions for centrally located lesions) or CRT (60 Gy in 15 fractions). The primary outcome of the study is 3-year local control, which we hypothesize will improve from 75% with CRT to 87.5% with SBRT. With 85% power to detect a difference of this magnitude (hazard ratio = 0.46), a 2-sided α = 0.05 and a 2:1 randomization, we require a sample size of 324 patients (216 SBRT, 108 CRT). Important secondary outcomes include overall survival, disease-free survival, toxicity, radiation-related treatment death, quality of life, and cost-effectiveness. A robust radiation therapy quality assurance program has been established to assure consistent and high quality SBRT and CRT delivery. Despite widespread interest and adoption of SBRT, there still remains a concern regarding long-term control and risks of toxicity (particularly in patients with centrally located lesions). The OCOG-LUSTRE study is the only randomized phase III trial testing SBRT in a medically inoperable population, and the results of this trial will attempt to prove that the benefits of SBRT outweigh the potential risks. Copyright © 2016 Elsevier Inc. All rights reserved.

The Role of Radiotherapy Alone in Patients With Merkel Cell Carcinoma: Reporting the Australian Experience of 43 Patients

DOE Office of Scientific and Technical Information (OSTI.GOV)

Veness, Michael, E-mail: michael.veness@swahs.health.nsw.gov.a; Foote, Matthew; Gebski, Val

2010-11-01

Purpose: To review the role of radiotherapy (RTx) alone in patients with Merkel cell carcinoma (MCC). Methods and Materials: The records of 43 patients with MCC treated with RTx alone between 1993 and 2007 at the Westmead and Royal Brisbane/Mater Hospitals, Australia, were reviewed. Multivariate analysis was performed by use of Cox regression analysis. Results: The median age was 79 years (range, 48-91 years) in 19 women (44%) and 24 men (56%). All patients were white, and 5 (12%) had immunosuppression. A majority (56%) underwent irradiation at initial diagnosis, with the remainder (44%) treated in the relapse setting. The medianmore » duration of follow-up was 39 months. The head and neck comprised the most frequently treated site (47%). The median maximum lesion size was 30 mm (range, 5-130 mm). Relapse developed in 60% of patients, with most being out-of-field relapses. The in-field control rate was 75%. Most out-of-field relapses were to visceral organs. Relapse developed outside the irradiated field in 53% of patients. On multivariate analysis, only nodal status (negative nodes vs. nodes present) was significantly associated with relapse-free survival, with p = 0.005 (hazard ratio, 0.25; 95% confidence interval, 0.96-0.663). Overall survival at 2 and 5 years was 58% and 37%, respectively. Conclusions: Patients with MCC treated with RTx have a high likelihood of obtaining in-field control. Doses of 50 to 55 Gy in 20 to 25 fractions are recommended. A minority of patients are cured, with many dying of systemic relapse. Lower dose fractionation schedules (e.g., 25 Gy in 5 fractions) may be considered in patients with a very poor performance status.« less

Therapeutic effect of high-dose three-dimensional conformal radiotherapy and conventional radiotherapy for non-small-cell lung cancer.

PubMed

Xu, Su-Jun; Shi, Yu-Sheng; Song, Hai-Chun; Chen, Long-Hua

2002-10-01

To improve the therapeutic effect of radiotherapy without increasing the risk of radiation injury in patients with non-small cell lung cancer (NSCLC). From August 1998 to August 1999, 135 patients with NSCLC received radiotherapy, of whom 62 were treated with high-dose three-dimensional conformal radiotherapy (3D-CRT) at the total dose of 48 to 64 Gy in 6 to 8 fractions implemented in a course of 2 to 3 weeks, 6 to 8 Gy for each fraction. The other 73 patients underwent conventional radiotherapy (CR) at the total dose of 60 to 70 Gy in 30 to 35 fractions completed in 6 to 7 weeks. Follow-up study was conducted in all the cases, and CT-scan or magnetic resonance imaging was performed once every 3 months after the therapy to assess the local control rate, survival rate, radiation-induced lung and esophageal injuries. Three months after radiation therapy, complete remission of the lesions was achieved in 44.9% (CR group) and 77.8% (3D-CRT group) of the cases with the efficacy rates of 94.4% and 100% respectively, showing significant differences between the 2 groups (P<0.01). The 1- and 2-year survival rate of the patients in the 2 groups were 42.5% vs 77.8% and 30.1% vs 48.6% respectively, also with significant differences between the 2 groups (P<0.01). Significant difference also occurred in the 1- and 2-year local control rates between the 2 groups, but not in the incidences of radiation-induced lung and esophageal injuries. 3D-CRT may yield better therapeutic effect than CR does and has comparable safety with the latter.

Toxicokinetics and toxicodynamics of chlorpyrifos is altered in embryos of Japanese medaka exposed to oil sands process-affected water: evidence for inhibition of P-glycoprotein.

PubMed

Alharbi, Hattan A; Alcorn, Jane; Al-Mousa, Ahmed; Giesy, John P; Wiseman, Steve B

2017-05-01

Oil sands process-affected water (OSPW) is generated during extraction of bitumen in the surface mining oil sands industry in Alberta, Canada. Studies were performed in vitro by use of Caco-2 cells, and in vivo with larvae of Japanese medaka (Oryzias latipes) to determine if organic compounds from the aqueous phase of OSPW inhibit ATP binding cassette protein ABCB1 (permeability-glycoprotein, P-gp). Neutral and basic fractions of OSPW inhibited activity of P-gp in Caco-2 cells by 1.9- and 2.0-fold, respectively, while the acidic fraction had the least effect. The organophosphate pesticides chlorpyrifos (a substrate of P-gp) and malathion (not a substrate of P-gp), were used as model chemicals to investigate inhibition of P-gp in larvae. Co-exposure to chlorpyrifos and an extract of OSPW containing basic and neutral compounds reduced survival of larvae to 26.5% compared to survival of larvae exposed only to chlorpyrifos, which was 93.7%. However, co-exposure to malathion and the extract of OSPW did not cause acute lethality compared to exposure only to malathion. Accumulation and bioconcentration of chlorpyrifos, but not malathion, was greater in larvae co-exposed with the extract of OSPW. The terminal elimination half-life of chlorpyrifos in larvae exposed to chlorpyrifos in freshwater was 5 days compared with 11.3 days in larvae exposed to chlorpyrifos in OSPW. Results suggest that in non-acute exposures, basic and neutral organic compounds in the water-soluble fraction of OSPW inhibit activity of P-gp, which suggests that OSPW has the potential to cause adverse effects by chemosensitization. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Applicability of the linear-quadratic formalism for modeling local tumor control probability in high dose per fraction stereotactic body radiotherapy for early stage non-small cell lung cancer.

PubMed

Guckenberger, Matthias; Klement, Rainer Johannes; Allgäuer, Michael; Appold, Steffen; Dieckmann, Karin; Ernst, Iris; Ganswindt, Ute; Holy, Richard; Nestle, Ursula; Nevinny-Stickel, Meinhard; Semrau, Sabine; Sterzing, Florian; Wittig, Andrea; Andratschke, Nicolaus; Flentje, Michael

2013-10-01

To compare the linear-quadratic (LQ) and the LQ-L formalism (linear cell survival curve beyond a threshold dose dT) for modeling local tumor control probability (TCP) in stereotactic body radiotherapy (SBRT) for stage I non-small cell lung cancer (NSCLC). This study is based on 395 patients from 13 German and Austrian centers treated with SBRT for stage I NSCLC. The median number of SBRT fractions was 3 (range 1-8) and median single fraction dose was 12.5 Gy (2.9-33 Gy); dose was prescribed to the median 65% PTV encompassing isodose (60-100%). Assuming an α/β-value of 10 Gy, we modeled TCP as a sigmoid-shaped function of the biologically effective dose (BED). Models were compared using maximum likelihood ratio tests as well as Bayes factors (BFs). There was strong evidence for a dose-response relationship in the total patient cohort (BFs>20), which was lacking in single-fraction SBRT (BFs<3). Using the PTV encompassing dose or maximum (isocentric) dose, our data indicated a LQ-L transition dose (dT) at 11 Gy (68% CI 8-14 Gy) or 22 Gy (14-42 Gy), respectively. However, the fit of the LQ-L models was not significantly better than a fit without the dT parameter (p=0.07, BF=2.1 and p=0.86, BF=0.8, respectively). Generally, isocentric doses resulted in much better dose-response relationships than PTV encompassing doses (BFs>20). Our data suggest accurate modeling of local tumor control in fractionated SBRT for stage I NSCLC with the traditional LQ formalism. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Using state variables to model the response of tumour cells to radiation and heat: a novel multi-hit-repair approach.

PubMed

Scheidegger, Stephan; Fuchs, Hans U; Zaugg, Kathrin; Bodis, Stephan; Füchslin, Rudolf M

2013-01-01

In order to overcome the limitations of the linear-quadratic model and include synergistic effects of heat and radiation, a novel radiobiological model is proposed. The model is based on a chain of cell populations which are characterized by the number of radiation induced damages (hits). Cells can shift downward along the chain by collecting hits and upward by a repair process. The repair process is governed by a repair probability which depends upon state variables used for a simplistic description of the impact of heat and radiation upon repair proteins. Based on the parameters used, populations up to 4-5 hits are relevant for the calculation of the survival. The model describes intuitively the mathematical behaviour of apoptotic and nonapoptotic cell death. Linear-quadratic-linear behaviour of the logarithmic cell survival, fractionation, and (with one exception) the dose rate dependencies are described correctly. The model covers the time gap dependence of the synergistic cell killing due to combined application of heat and radiation, but further validation of the proposed approach based on experimental data is needed. However, the model offers a work bench for testing different biological concepts of damage induction, repair, and statistical approaches for calculating the variables of state.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ai, H; Zhang, H

Purpose: To evaluate normal tissue toxicity in patients with head and neck cancer by calculating average survival fraction (SF) and equivalent uniform dose (EUD) for normal tissue cells. Methods: 20 patients with head and neck cancer were included in this study. IMRT plans were generated using EclipseTM treatment planning system by dosimetrist following clinical radiotherapy treatment guidelines. The average SF for three different normal tissue cells of each concerned structure can be calculated from dose spectrum acquired from differential dose volume histogram (DVH) using linear quadratic model. The three types of normal tissues include radiosensitive, moderately radiosensitive and radio-resistant thatmore » represents 70%, 50% and 30% survival fractions, respectively, for a 2-Gy open field. Finally, EUDs for three types of normal tissue of each structure were calculated from average SF. Results: The EUDs of the brainstem, spinal cord, parotid glands, brachial plexus and etc were calculated. Our analysis indicated that the brainstem can absorb as much as 14.3% of prescription dose to the tumor if the cell line is radiosensitive. In addition, as much as 16.1% and 18.3% of prescription dose were absorbed by the brainstem for moderately radiosensitive and radio-resistant cells, respectively. For the spinal cord, the EUDs reached up to 27.6%, 35.0% and 42.9% of prescribed dose for the three types of radiosensitivities respectively. Three types of normal cells for parotid glands can get up to 65.6%, 71.2% and 78.4% of prescription dose, respectively. The maximum EUDs of brachial plexsus were calculated as 75.4%, 76.4% and 76.7% of prescription for three types of normal cell lines. Conclusion: The results indicated that EUD can be used to quantify and evaluate the radiation damage to surrounding normal tissues. Large variation of normal tissue EUDs may come from variation of target volumes and radiation beam orientations among the patients.« less

mBAND Analysis of Late Chromosome Aberrations in Human Lymphocytes Induced by Gamma Rays and Fe Ions

NASA Technical Reports Server (NTRS)

Sunagawa, Mayumi; Zhang, Ye; Yeshitla, Samrawit; Kadhim, Munira; Wilson, Bobby; Wu, Honglu

2014-01-01

Chromosomal translocations and inversions are considered stable, and cells containing these types of chromosome aberrations can survive multiple cell divisions. An efficient method to detect an inversion is multi-color banding fluorescent in situ hybridization (mBAND) which allows identification of both inter- and intrachromosome aberrations simultaneously. Post irradiation, chromosome aberrations may also arise after multiple cell divisions as a result of genomic instability. To investigate the stable or late-arising chromosome aberrations induced after radiation exposure, we exposed human lymphocytes to gamma rays and Fe ions ex vivo, and cultured the cells for multiple generations. Chromosome aberrations were analyzed in cells collected at first mitosis and at several time intervals during the culture period post irradiation. With gamma irradiation, about half of the damages observed at first mitosis remained after 7 day- and 14 day- culture, suggesting the transmissibility of damages to the surviving progeny. Detailed analysis of chromosome break ends participating in exchanges revealed a greater fraction of break ends involved in intrachromosome aberrations in the 7- and 14-day samples in comparison to the fraction at first mitosis. In particular, simple inversions were found at 7 and 14 days, but not at the first mitosis, suggesting that some of the aberrations might be formed days post irradiation. In contrast, at the doses that produced similar frequencies of gamma-induced chromosome aberrations as observed at first mitosis, a significantly lower yield of aberrations remained at the same population doublings after Fe ion exposure. At these equitoxic doses, more complex type aberrations were observed for Fe ions, indicating that Fe ion-induced initial chromosome damages are more severe and may lead to cell death. Comparison between low and high doses of Fe ion irradiation in the induction of late damages will also be discussed.

Neuroprotective and Anti-Inflammatory Effects of the Flavonoid-Enriched Fraction AF4 in a Mouse Model of Hypoxic-Ischemic Brain Injury

PubMed Central

Keddy, Paul G. W.; Dunlop, Kate; Warford, Jordan; Samson, Michel L.; Jones, Quinton R. D.; Rupasinghe, H. P. Vasantha; Robertson, George S.

2012-01-01

We report here neuroprotective and anti-inflammatory effects of a flavonoid-enriched fraction isolated from the peel of Northern Spy apples (AF4) in a mouse of model of hypoxic-ischemic (HI) brain damage. Oral administration of AF4 (50 mg/kg, once daily for 3 days) prior to 50 min of HI completely prevented motor performance deficits assessed 14 days later that were associated with marked reductions in neuronal cell loss in the dorsal hippocampus and striatum. Pre-treatment with AF4 (5, 10, 25 or 50 mg/kg, p.o.; once daily for 3 days) produced a dose-dependent reduction in HI-induced hippocampal and striatal neuron cell loss, with 25 mg/kg being the lowest dose that achieved maximal neuroprotection. Comparison of the effects of 1, 3 or 7 doses of AF4 (25 mg/kg; p.o.) prior to HI revealed that at least 3 doses of AF4 were required before HI to reduce neuronal cell loss in both the dorsal hippocampus and striatum. Quantitative RT-PCR measurements revealed that the neuroprotective effects of AF4 (25 mg/kg; p.o.; once daily for 3 days) in the dorsal hippocampus were associated with a suppression of HI-induced increases in the expression of IL-1β, TNF-α and IL-6. AF4 pre-treatment enhanced mRNA levels for pro-survival proteins such as X-linked inhibitor of apoptosis and erythropoietin following HI in the dorsal hippocampus and striatum, respectively. Primary cultures of mouse cortical neurons incubated with AF4 (1 µg/ml), but not the same concentrations of either quercetin or quercetin-3-O-glucose or its metabolites, were resistant to cell death induced by oxygen glucose deprivation. These findings suggest that the inhibition of HI-induced brain injury produced by AF4 likely involves a transcriptional mechanism resulting from the co-operative actions of various phenolics in this fraction which not only reduce the expression of pro-inflammatory mediators but also enhance pro-survival gene signalling. PMID:23251498

Stereotactic Radiosurgery and Fractionated Stereotactic Radiation Therapy for the Treatment of Uveal Melanoma

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yazici, Gozde; Kiratli, Hayyam; Ozyigit, Gokhan

Purpose: To evaluate treatment results of stereotactic radiosurgery or fractionated stereotactic radiation therapy (SRS/FSRT) for uveal melanoma. Methods and Materials: We retrospectively evaluated 181 patients with 182 uveal melanomas receiving SRS/FSRT between 2007 and 2013. Treatment was administered with CyberKnife. Results: According to Collaborative Ocular Melanoma Study criteria, tumor size was small in 1%, medium in 49.5%, and large in 49.5% of the patients. Seventy-one tumors received <45 Gy, and 111 received ≥45 Gy. Median follow-up time was 24 months. Complete and partial response was observed in 8 and 104 eyes, respectively. The rate of 5-year overall survival was 98%, disease-free survival 57%,more » local recurrence-free survival 73%, distant metastasis-free survival 69%, and enucleation-free survival 73%. There was a significant correlation between tumor size and disease-free survival, SRS/FSRT dose and enucleation-free survival; and both were prognostic for local recurrence-free survival. Enucleation was performed in 41 eyes owing to progression in 26 and complications in 11. Conclusions: The radiation therapy dose is of great importance for local control and eye retention; the best treatment outcome was achieved using ≥45 Gy in 3 fractions.« less

Accelerated hypofractionated three-dimensional conformal radiation therapy (3 Gy/fraction) combined with concurrent chemotherapy for patients with unresectable stage III non-small cell lung cancer: preliminary results of an early terminated phase II trial.

PubMed

Ren, Xiao-Cang; Wang, Quan-Yu; Zhang, Rui; Chen, Xue-Ji; Wang, Na; Liu, Yue-E; Zong, Jie; Guo, Zhi-Jun; Wang, Dong-Ying; Lin, Qiang

2016-04-23

Increasing the biological effective dose (BED) of radiotherapy for non-small cell lung cancer (NSCLC) can increase local control rates and improve overall survival. Compared with conventional fractionated radiotherapy, accelerated hypofractionated radiotherapy can yield higher BED, shorten the total treatment time, and theoretically obtain better efficacy. However, currently, there is no optimal hypofractionated radiotherapy regimen. Based on phase I trial results, we performed this phase II trial to further evaluate the safety and preliminary efficacy of accelerated hypofractionated three-dimensional conformal radiation therapy(3-DCRT) combined with concurrent chemotherapy for patients with unresectable stage III NSCLC. Patients with previously untreated unresectable stage III NSCLC received 3-DCRT with a total dose of 69 Gy, delivered at 3 Gy per fraction, once daily, five fractions per week, completed within 4.6 weeks. At the same time, platinum doublet chemotherapy was applied. After 12 patients were enrolled in the group, the trial was terminated early. There were five cases of grade III radiation esophagitis, of which four cases completed the radiation doses of 51 Gy, 51 Gy, 54 Gy, and 66 Gy, and one case had 16 days of radiation interruption. The incidence of grade III acute esophagitis in patients receiving an irradiation dose per fraction ≥2.7 Gy on the esophagus was 83.3% (5/6). The incidence of symptomatic grade III radiation pneumonitis among the seven patients who completed 69 Gy according to the plan was 28.6% (2/7). The median local control (LC) and overall survival (OS) were not achieved; the 1-year LC rate was 59.3%, and the 1-year OS rate was 78.6%. For unresectable stage III NSCLC, the accelerated hypofractionated radiotherapy with a total dose of 69 Gy (3 Gy/f) combined with concurrent chemotherapy might result in severe radiation esophagitis and pneumonitis to severely affect the completion of the radiotherapy. Therefore, we considered that this regimen was infeasible. During the hypofractionated radiotherapy with concurrent chemotherapy, the irradiation dose per fraction to esophagus should be lower than 2.7 Gy. Further studies should be performed using esophageal tolerance as a metric in dose escalation protocols. NCT02720614, the date of registration: March 23, 2016.

Characteristics of Myeloid Differentiation and Maturation Pathway Derived from Human Hematopoietic Stem Cells Exposed to Different Linear Energy Transfer Radiation Types

PubMed Central

Monzen, Satoru; Yoshino, Hironori; Kasai-Eguchi, Kiyomi; Kashiwakura, Ikuo

2013-01-01

Exposure of hematopoietic stem/progenitor cells (HSPCs) to ionizing radiation causes a marked suppression of mature functional blood cell production in a linear energy transfer (LET)- and/or dose-dependent manner. However, little information about LET effects on the proliferation and differentiation of HSPCs has been reported. With the aim of characterizing the effects of different types of LET radiations on human myeloid hematopoiesis, in vitro hematopoiesis in Human CD34+ cells exposed to carbon-ion beams or X-rays was compared. Highly purified CD34+ cells exposed to each form of radiation were plated onto semi-solid culture for a myeloid progenitor assay. The surviving fractions of total myeloid progenitors, colony-forming cells (CFC), exposed to carbon-ion beams were significantly lower than of those exposed to X-rays, indicating that CFCs are more sensitive to carbon-ion beams (D 0 = 0.65) than to X-rays (D 0 = 1.07). Similar sensitivities were observed in granulocyte-macrophage and erythroid progenitors, respectively. However, the sensitivities of mixed-type progenitors to both radiation types were similar. In liquid culture for 14 days, no significant difference in total numbers of mononuclear cells was observed between non-irradiated control culture and cells exposed to 0.5 Gy X-rays, whereas 0.5 Gy carbon-ion beams suppressed cell proliferation to 4.9% of the control, a level similar to that for cells exposed to 1.5 Gy X-rays. Cell surface antigens associated with terminal maturation, such as CD13, CD14, and CD15, on harvest from the culture of X-ray-exposed cells were almost the same as those from the non-irradiated control culture. X-rays increased the CD235a+ erythroid-related fraction, whereas carbon-ion beams increased the CD34+CD38− primitive cell fraction and the CD13+CD14+/−CD15− fraction. These results suggest that carbon-ion beams inflict severe damage on the clonal growth of myeloid HSPCs, although the intensity of cell surface antigen expression by mature myeloid cells derived from HSPCs exposed to each type of radiation was similar to that by controls. PMID:23555027

Radiation-induced transmissable chromosomal instability in haemopoietic stem cells

NASA Astrophysics Data System (ADS)

Kadhim, M. A.; Wright, E. G.

Heritable radiation-induced genetic alterations have long been assumed to be ``fixed'' within the first cell division. However, there is a growing body of evidence that a considerable fraction of cells surviving radiation exposure appear normal, but a variety of mutational changes arise in their progeny due to a transmissible genomic instability. In our investigations of G-banded metaphases, non-clonal cytogenetic aberrations, predominantly chromatid-type aberrations, have been observed in the clonal descendants of murine and human haemopoietic stem cells surviving low doses (~1 track per cell) of alpha-particle irradiations. The data are consistent with a transmissible genetic instability induced in a stem cell resulting in a diversity of chromosomal aberrations in its clonal progeny many cell divisions later. Recent studies have demonstrated that the instability phenotype persists in vivo and that the expression of chromosomal instability has a strong dependence on the genetic characteristics of the irradiated cell. At the time when cytogenetic aberrations are detected, an increased incidence of hprt mutations and apoptotic cells have been observed in the clonal descendants of alpha-irradiated murine haemopoietic stem cells. Thus, delayed chromosomal abnormalities, delayed cell death by apoptosis and late-arising specific gene mutations may reflect diverse consequences of radiation-induced genomic instability. The relationship, if any, between these effects is not established. Current studies suggest that expression of these delayed heritable effects is determined by the type of radiation exposure, type of cell and a variety of genetic factors.

Relative biological effectiveness (RBE) of alpha radiation in cultured porcine aortic endothelial cells.

PubMed

Thomas, Patricia; Tracy, Bliss; Ping, Tilly; Baweja, Anar; Wickstrom, Mark; Sidhu, Narinder; Hiebert, Linda

2007-03-01

Northern peoples can receive elevated radiation doses (1- 10 mSv/y) from transfer of polonium-210 (210Po) through the lichen-caribou-human food chain. Ingested 210Po is primarily blood-borne and thus many of its short range alpha particles irradiate the endothelial cells lining the blood vessels. The relative biological effectiveness (RBE) of alpha particles vs. x-rays was examined in porcine aortic endothelial cells as a surrogate for understanding what might happen to human endothelial cells in northern populations consuming traditional foods. Cultured porcine aortic endothelial cells were exposed to x-ray and 210Po alpha particle radiation. Alpha irradiation was applied to the cell cultures internally via the culture medium and externally, using thin-bottomed culture dishes. The results given here are based on the external irradiation method, which was found to be more reliable. Dose-response curves were compared for four lethal endpoints (cell viability, live cell fraction, release of lactate dehydrogenase [LDH] and clonogenic survival) to determine the relative biological effectiveness (RBE) of alpha radiation. The alpha RBE for porcine cells varied from 1.6-21, depending on the endpoint: 21.2+/-4.5 for cell viability, 12.9+/-2.7 for decrease in live cell number, 5.3+/-0.4 for LDH release to the medium but only 1.6 +/-0.1 for clonogenic survival. The low RBE of 1.6 was due to x-ray hypersensitivity of endothelial cells at low doses.

A Possible Phenomenon of Persistence in Pseudomonas aeruginosa Treated with Methylene Blue and Red Light.

PubMed

Forte Giacobone, Ana Florencia; Ruiz Gale, Maria Fernanda; Hogert, Elsa Noemí; Oppezzo, Oscar Juan

2016-09-01

Planktonic Pseudomonas aeruginosa cells harvested in stationary phase were exposed to red light in the presence of methylene blue to study the potential occurrence of persistence in bacterial populations submitted to photodynamic antimicrobial therapy. Survival curves revealed the existence of small subpopulations of cells exhibiting increased ability to tolerate the treatment. These subpopulations were detected even using high concentrations of photosensitizer, whether added in a single step or following a fractionated scheme, and when the irradiation medium was modified to delay the photodecomposition of methylene blue. When cells grown from survivors to the treatment were cultured and exposed to red light and dye, their responses were similar to that of the original strain. These results exclude exhaustion of the photosensitizer and selection of resistant mutants as explanations for the features of the survival curves. Cells able to tolerate the treatment were found even when radiation was imparted at a high-dose rate. They exhibit a response typical of persisters, which tolerate antimicrobial agents due to transient and reversible changes in their phenotype, suggesting that persistence is a factor to consider upon evaluating the efficacy of photodynamic antimicrobial therapy. © 2016 The American Society of Photobiology.

Enhancing cancer therapeutics using size-optimized magnetic fluid hyperthermia

NASA Astrophysics Data System (ADS)

Khandhar, Amit P.; Ferguson, R. Matthew; Simon, Julian A.; Krishnan, Kannan M.

2012-04-01

Magnetic fluid hyperthermia (MFH) employs heat dissipation from magnetic nanoparticles to elicit a therapeutic outcome in tumor sites, which results in either cell death (>42 °C) or damage (<42 °C) depending on the localized rise in temperature. We investigated the therapeutic effect of MFH in immortalized T lymphocyte (Jurkat) cells using monodisperse magnetite (Fe3O4) nanoparticles (MNPs) synthesized in organic solvents and subsequently transferred to aqueous phase using a biocompatible amphiphilic polymer. Monodisperse MNPs, ˜16 nm diameter, show maximum heating efficiency, or specific loss power (watts/g Fe3O4) in a 373 kHz alternating magnetic field. Our in vitro results, for 15 min of heating, show that only 40% of cells survive for a relatively low dose (490 μg Fe/ml) of these size-optimized MNPs, compared to 80% and 90% survival fraction for 12 and 13 nm MNPs at 600 μg Fe/ml. The significant decrease in cell viability due to MNP-induced hyperthermia from only size-optimized nanoparticles demonstrates the central idea of tailoring size for a specific frequency in order to intrinsically improve the therapeutic potency of MFH by optimizing both dose and time of application.

IL-6 Inhibition With MEDI5117 Decreases The Fraction of Head and Neck Cancer Stem Cells and Prevents Tumor Recurrence.

PubMed

Finkel, Kelsey A; Warner, Kristy A; Kerk, Samuel; Bradford, Carol R; McLean, Scott A; Prince, Mark E; Zhong, Haihong; Hurt, Elaine M; Hollingsworth, Robert E; Wicha, Max S; Tice, David A; Nör, Jacques E

2016-05-01

Head and neck squamous cell carcinomas (HNSCC) exhibit a small population of uniquely tumorigenic cancer stem cells (CSC) endowed with self-renewal and multipotency. We have recently shown that IL-6 enhances the survival and tumorigenic potential of head and neck cancer stem cells (i.e. ALDH(high)CD44(high) cells). Here, we characterized the effect of therapeutic inhibition of IL-6 with a novel humanized anti-IL-6 antibody (MEDI5117) using three low-passage patient-derived xenograft (PDX) models of HNSCC. We observed that single agent MEDI5117 inhibited the growth of PDX-SCC-M1 tumors (P < .05). This PDX model was generated from a previously untreated HNSCC. In contrast, MEDI5117 was not effective at reducing overall tumor volume for PDX models representing resistant disease (PDX-SCC-M0, PDX-SCC-M11). Low dose MEDI5117 (3 mg/kg) consistently decreased the fraction of cancer stem cells in PDX models of HNSCC when compared to IgG-treated controls, as follows: PDX-SCC-M0 (P < .001), PDX-SCC-M1 (P < .001), PDX-SCC-M11 (P = .04). Interestingly, high dose MEDI5117 (30 mg/kg) decreased the CSC fraction in the PDX-SCC-M11 model (P = .002), but not in PDX-SCC-M0 and PDX-SCC-M1. MEDI5117 mediated a dose-dependent decrease in the number of orospheres generated by ALDH(high)CD44(high) cells cultured in ultra-low attachment plates (P < .05), supporting an inhibitory effect on head and neck cancer stem cells. Notably, single agent MEDI5117 reduced the overall recurrence rate of PDX-SCC-M0, a PDX generated from the local recurrence of human HNSCC. Collectively, these data demonstrate that therapeutic inhibition of IL-6 with low-dose MEDI5117 decreases the fraction of cancer stem cells, and that adjuvant MEDI5117 inhibits recurrence in preclinical models of HNSCC. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Intracerebral Cell Implantation: Preparation and Characterization of Cell Suspensions.

PubMed

Rossetti, Tiziana; Nicholls, Francesca; Modo, Michel

2016-01-01

Intracerebral cell transplantation is increasingly finding a clinical translation. However, the number of cells surviving after implantation is low (5-10%) compared to the number of cells injected. Although significant efforts have been made with regard to the investigation of apoptosis of cells after implantation, very little optimization of cell preparation and administration has been undertaken. Moreover, there is a general neglect of the biophysical aspects of cell injection. Cell transplantation can only be an efficient therapeutic approach if an optimal transfer of cells from the dish to the brain can be ensured. We therefore focused on the in vitro aspects of cell preparation of a clinical-grade human neural stem cell (NSC) line for intracerebral cell implantation. NSCs were suspended in five different vehicles: phosphate-buffered saline (PBS), Dulbecco's modified Eagle medium (DMEM), artificial cerebral spinal fluid (aCSF), HypoThermosol, and Pluronic. Suspension accuracy, consistency, and cell settling were determined for different cell volume fractions in addition to cell viability, cell membrane damage, and clumping. Maintenance of cells in suspension was evaluated while being stored for 8 h on ice, at room temperature, or physiological normothermia. Significant differences between suspension vehicles and cellular volume fractions were evident. HypoThermosol and Pluronic performed best, with PBS, aCSF, and DMEM exhibiting less consistency, especially in maintaining a suspension and preserving viability under different storage conditions. These results provide the basis to further investigate these preparation parameters during the intracerebral delivery of NSCs to provide an optimized delivery process that can ensure an efficient clinical translation.

Radiosensitization of head/neck sqaumous cell carcinoma by adenovirus-mediated expression of the Nbs1 protein

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rhee, Juong G.; Marlene and Stewart Greenebaum Cancer Center, University of Maryland School of Medicine, Baltimore, MD; Li, Daqing

2007-01-01

Purpose: Local failure and toxicity to adjacent critical structures is a significant problem in radiation therapy of cancers of the head and neck. We are developing a gene therapy based method of sensitizing head/neck squamous cell carcinoma (HNSCC) to radiation treatment. As patients with the rare hereditary disorder, Nijmegen breakage syndrome, show radiation sensitivity we hypothesized that tumor-specific disruption of the function of the Nbs1 protein would lead to enhanced cellular sensitivity to ionizing radiation. Experimental Procedures: We constructed two recombinant adenoviruses by cloning the full-length Nbs1 cDNA as well as the C-terminal 300 amino acids of Nbs1 into anmore » adenovirus backbone under the control of a CMV promoter. The resulting adenoviruses were used to infect HNSCC cell line JHU011. These cells were evaluated for expression of the viral based constructs and assayed for clonogenic survival following radiation exposure. Results: Exposure of cells expressing Nbs1-300 to ionizing radiation resulted in a small reduction in survival relative to cells infected with control virus. Surprisingly, expression of full-length Nbs1 protein resulted in markedly enhanced sensitivity to ionizing radiation. Furthermore, the use of a fractionated radiation scheme following virus infection demonstrates that expression of full-length Nbs1 protein results in significant reduction in cell survival. Conclusions: These results provide a proof of principle that disruption of Nbs1 function may provide a means of enhancing the radiosensitivity of head and neck tumors. Additionally, this work highlights the Mre11 complex as an attractive target for development of radiation sensitizers.« less

Low osmolality and shear stress during liposuction impair cell viability in autologous fat grafting.

PubMed

Ismail, T; Bürgin, J; Todorov, A; Osinga, R; Menzi, N; Largo, R D; Haug, M; Martin, I; Scherberich, A; Schaefer, D J

2017-05-01

Liposuction and subsequent autologous fat grafting have become essential techniques for fat augmentation in plastic surgery. However, standard harvesting techniques that ensure the survival of adipocytes and stromal vascular fraction (SVF) cells and thus preserve the transplanted fat volume are lacking. In particular, the effect of different parameters of the tumescent solution has not been studied in this context. We hypothesized that the osmolality of the tumescent solution could have a significant effect on the survival of adipocytes and SVF cells. We developed two distinct in vitro models based on freshly harvested excision fat from patients undergoing surgical treatment. First, we investigated the effect of osmolality by incubating excision fat in different tumescent solutions and analyzed the total cell survival and the differentiation potential of SVF cells. Vital whole-mount staining, isolation yield of SVF cells, clonogenicity, and osteogenic and adipogenic differentiation capacities were analyzed. Second, we addressed the additional effect of mechanical stress by simulating a liposuction on pieces of excision fat after incubation with the tumescent solutions. Osmolality of the tumescent solution by itself did not have a significant effect on adipocyte and SVF viability or SVF differentiation. However, when osmolality was combined with liposuction, a significant trend toward lower viability and more lipid droplets with lower osmolality was observed. Especially, SVF viability was significantly lower after liposuction with a hypotonic (150 mOsm/kg) solution. This study demonstrates the considerable effect of osmolality during liposuction and may lead to the development of "cell-protective" tumescent solutions. Copyright © 2017 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

IGF-1-overexpressing mesenchymal stem cells accelerate bone marrow stem cell mobilization via paracrine activation of SDF-1alpha/CXCR4 signaling to promote myocardial repair.

PubMed

Haider, Husnain Kh; Jiang, Shujia; Idris, Niagara M; Ashraf, Muhammad

2008-11-21

We hypothesized that mesenchymal stem cells (MSCs) overexpressing insulin-like growth factor (IGF)-1 showed improved survival and engraftment in the infarcted heart and promoted stem cell recruitment through paracrine release of stromal cell-derived factor (SDF)-1alpha. Rat bone marrow-derived MSCs were used as nontransduced ((Norm)MSCs) or transduced with adenoviral-null vector ((Null)MSCs) or vector encoding for IGF-1 ((IGF-1)MSCs). (IGF-1)MSCs secreted higher IGF-1 until 12 days of observation (P<0.001 versus (Null)MSCs). Molecular studies revealed activation of phosphoinositide 3-kinase, Akt, and Bcl.xL and inhibition of glycogen synthase kinase 3beta besides release of SDF-1alpha in parallel with IGF-1 expression in (IGF-1)MSCs. For in vivo studies, 70 muL of DMEM without cells (group 1) or containing 1.5x10(6) (Null)MSCs (group 2) or (IGF-1)MSCs (group 3) were implanted intramyocardially in a female rat model of permanent coronary artery occlusion. One week later, immunoblot on rat heart tissue (n=4 per group) showed elevated myocardial IGF-1 and phospho-Akt in group 3 and higher survival of (IGF-1)MSCs (P<0.06 versus (Null)MSCs) (n=6 per group). SDF-1alpha was increased in group 3 animal hearts (20-fold versus group 2), with massive mobilization and homing of ckit(+), MDR1(+), CD31(+), and CD34(+) cells into the infarcted heart. Infarction size was significantly reduced in cell transplanted groups compared with the control. Confocal imaging after immunostaining for myosin heavy chain, actinin, connexin-43, and von Willebrand factor VIII showed extensive angiomyogenesis in the infarcted heart. Indices of left ventricular function, including ejection fraction and fractional shortening, were improved in group 3 as compared with group 1 (P<0.05). In conclusion, the strategy of IGF-1 transgene expression induced massive stem cell mobilization via SDF-1alpha signaling and culminated in extensive angiomyogenesis in the infarcted heart.

microRNA-451a regulates colorectal cancer proliferation in response to radiation.

PubMed

Ruhl, Rebecca; Rana, Shushan; Kelley, Katherine; Espinosa-Diez, Cristina; Hudson, Clayton; Lanciault, Christian; Thomas, Charles R; Liana Tsikitis, V; Anand, Sudarshan

2018-05-03

Colorectal cancer (CRC) is a leading cause of cancer-related death. The biologic response of CRC to standard of care adjuvant therapies such as chemotherapy and radiation are poorly understood. MicroRNAs (miRs) have been shown to affect CRC progression and metastasis. Therefore, we hypothesized that specific miRs modulate CRC response to chemoradiation. In this study, we used miR expression profiling and discovered a set of microRNAs upregulated rapidly in response to either a single 2 Gy dose fraction or a 10 Gy dose of γ-radiation in mouse colorectal carcinoma models. We used gain and loss-of-function studies in 2D and 3Dcell proliferation assays and colony formation assays to understand the role of the top miR candidate from our profiling. We used Student's T-tests for simple comparisons and two-factor ANOVA for evaluating significance. The most upregulated candidate at early time points in our signature, miR-451a inhibited tumor cell proliferation and attenuated surviving fraction in longer-term cultures. Conversely, inhibition of miR-451a increased proliferation, tumorsphere formation, and surviving fraction of tumor cells. Using a bioinformatics approach, we identified four genes, CAB39, EMSY, MEX3C, and EREG, as targets of miR-451a. Transfection of miR-451a decreased both mRNA and protein levels of these targets. Importantly, we found miR-451a expression was high and CAB39, EMSY levels were low in a small subset of rectal cancer patients who had a partial response to chemoradiation when compared to patients that had no response. Finally, analysis of a TCGA colorectal cancer dataset revealed that CAB39 and EMSY are upregulated at the protein level in a significant number of CRC patients. Higher levels of CAB39 and EMSY correlated with poorer overall survival. Taken together, our data indicates miR-451a is induced by radiation and may influence colorectal carcinoma proliferation via CAB39 and EMSY pathways.

Biochemical and functional characterization of MRA-1571 of Mycobacterium tuberculosis H37Ra and effect of its down-regulation on survival in macrophages

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sharma, Rishabh; Keshari, Deepa; Singh, Kumar Sachin

Amino acid biosynthesis has emerged as a source of new drug targets as many bacterial strains auxotrophic for amino acids fail to proliferate under in vivo conditions. Branch chain amino acids (BCAAs) are important for Mycobacterium tuberculosis (Mtb) survival and strains deficient in their biosynthesis were attenuated for growth in mice. Threonine dehydratase (IlvA) is a pyridoxal-5-phosphate (PLP) dependent enzyme that catalyzes the first step in isoleucine biosynthesis. The MRA-1571 of Mycobacterium tuberculosis H37Ra (Mtb-Ra), annotated to be coding for IlvA, was cloned, expressed and purified. Purified protein was subsequently used for developing enzyme assay and to study its biochemical properties.more » Also, E. coli BL21 (DE3) IlvA knockout (E. coli-ΔilvA) was developed and genetically complemented with Mtb-Ra ilvA expression construct (pET32a-ilvA) to make complemented E. coli strain (E. coli-ΔilvA + pET32a-ilvA). The E. coli-ΔilvA showed growth failure in minimal medium but growth restoration was observed in E. coli-ΔilvA + pET32a-ilvA. E. coli-ΔilvA growth was also restored in the presence of isoleucine. The IlvA localization studies detected its distribution in cell wall and membrane fractions with relatively minor presence in cytosolic fraction. Maximum IlvA expression was observed at 72 h in wild-type (WT) Mtb-Ra infecting macrophages. Also, Mtb-Ra IlvA knockdown (KD) showed reduced survival in macrophages compared to WT and complemented strain (KDC). - Highlights: • Mtb-Ra gene MRA-1571 codes for a functional threonine dehydratase (IlvA). • IlvA is pyridoxal 5’-phosphate dependent and is inhibited by isoleucine. • E. coli IlvA knockout growth can be supplemented by isoleucine or by Mtb-Ra IlvA. • The enzyme is primarily localized in cell wall and membrane fractions. • IlvA knockdown Mtb-Ra shows reduced growth in macrophages.« less

The vascular disrupting agent ZD6126 shows increased antitumor efficacy and enhanced radiation response in large, advanced tumors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Siemann, Dietmar W.; Rojiani, Amyn M.

2005-07-01

Purpose: ZD6126 is a vascular-targeting agent that induces selective effects on the morphology of proliferating and immature endothelial cells by disrupting the tubulin cytoskeleton. The efficacy of ZD6126 was investigated in large vs. small tumors in a variety of animal models. Methods and Materials: Three rodent tumor models (KHT, SCCVII, RIF-1) and three human tumor xenografts (Caki-1, KSY-1, SKBR3) were used. Mice bearing leg tumors ranging in size from 0.1-2.0 g were injected intraperitoneally with a single 150 mg/kg dose of ZD6126. The response was assessed by morphologic and morphometric means as well as an in vivo to in vitromore » clonogenic cell survival assay. To examine the impact of tumor size on the extent of enhancement of radiation efficacy by ZD6126, KHT sarcomas of three different sizes were irradiated locally with a range of radiation doses, and cell survival was determined. Results: All rodent tumors and human tumor xenografts evaluated showed a strong correlation between increasing tumor size and treatment effect as determined by clonogenic cell survival. Detailed evaluation of KHT sarcomas treated with ZD6126 showed a reduction in patent tumor blood vessels that was {approx}20% in small (<0.3 g) vs. >90% in large (>1.0 g) tumors. Histologic assessment revealed that the extent of tumor necrosis after ZD6126 treatment, although minimal in small KHT sarcomas, became more extensive with increasing tumor size. Clonogenic cell survival after ZD6126 exposure showed a decrease in tumor surviving fraction from approximately 3 x 10{sup -1} to 1 x 10{sup -4} with increasing tumor size. When combined with radiotherapy, ZD6126 treatment resulted in little enhancement of the antitumor effect of radiation in small (<0.3 g) tumors but marked increases in cell kill in tumors larger than 1.0 g. Conclusions: Because bulky neoplastic disease is typically the most difficult to manage, the present findings provide further support for the continued development of vascular disrupting agents such as ZD6126 as a vascular-targeted approach to cancer therapy.« less

STAT3-Activated GM-CSFRα Translocates to the Nucleus and Protects CLL Cells from Apoptosis

PubMed Central

Li, Ping; Harris, David; Liu, Zhiming; Rozovski, Uri; Ferrajoli, Alessandra; Wang, Yongtao; Bueso-Ramos, Carlos; Hazan-Halevy, Inbal; Grgurevic, Srdana; Wierda, William; Burger, Jan; O'Brien, Susan; Faderl, Stefan; Keating, Michael; Estrov, Zeev

2014-01-01

Here it was determined that Chronic Lymphocytic Leukemia (CLL) cells express the α-subunit but not the β-subunit of the granulocyte-macrophage colony-stimulating factor receptor (GM-CSFR/CSF3R). GM-CSFRα was detected on the surface, in the cytosol, and the nucleus of CLL cells via confocal microscopy, cell fractionation, and GM-CSFRα antibody epitope mapping. Because STAT3 is frequently activated in CLL and the GM-CSFRα promoter harbors putative STAT3 consensus binding sites, MM1 cells were transfected with truncated forms of the GM-CSFRα promoter, then stimulated with IL-6 to activate STAT3 to identify STAT3 binding sites. Chromatin immunoprecipitation (ChIP) and an electoromobility shift assay (EMSA) confirmed STAT3 occupancy to those promoter regions in both IL-6 stimulated MM1 and CLL cells. Transfection of MM1 cells with STAT3 siRNA or CLL cells with STAT3 shRNA significantly down-regulated GM-CSFRα mRNA and protein levels. RNA transcripts, involved in regulating cell-survival pathways, and the proteins KAP1 (TRIM28) and ISG15 co-immunoprecipitated with GM-CSFRα. GM-CSFRα-bound KAP1 enhanced the transcriptional activity of STAT3, whereas ISG15 inhibited the NF-κB pathway. Nevertheless, overexpression of GM-CSFRα protected MM1 cells from dexamethasone-induced apoptosis, and GM-CSFRα knockdown induced apoptosis in CLL cells, suggesting that GM-CSFRα provides a ligand-independent survival advantage. PMID:24836891

Tumor Control Outcomes After Hypofractionated and Single-Dose Stereotactic Image-Guided Intensity-Modulated Radiotherapy for Extracranial Metastases From Renal Cell Carcinoma

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zelefsky, Michael J., E-mail: zelefskm@mskcc.org; Greco, Carlo; Motzer, Robert

2012-04-01

Purpose: To report tumor local progression-free outcomes after treatment with single-dose, image-guided, intensity-modulated radiotherapy and hypofractionated regimens for extracranial metastases from renal cell primary tumors. Patients and Methods: Between 2004 and 2010, 105 lesions from renal cell carcinoma were treated with either single-dose, image-guided, intensity-modulated radiotherapy to a prescription dose of 18-24 Gy (median, 24) or hypofractionation (three or five fractions) with a prescription dose of 20-30 Gy. The median follow-up was 12 months (range, 1-48). Results: The overall 3-year actuarial local progression-free survival for all lesions was 44%. The 3-year local progression-free survival for those who received a highmore » single-dose (24 Gy; n = 45), a low single-dose (<24 Gy; n = 14), or hypofractionation regimens (n = 46) was 88%, 21%, and 17%, respectively (high single dose vs. low single dose, p = .001; high single dose vs. hypofractionation, p < .001). Multivariate analysis revealed the following variables were significant predictors of improved local progression-free survival: 24 Gy dose compared with a lower dose (p = .009) and a single dose vs. hypofractionation (p = .008). Conclusion: High single-dose, image-guided, intensity-modulated radiotherapy is a noninvasive procedure resulting in high probability of local tumor control for metastatic renal cell cancer generally considered radioresistant according to the classic radiobiologic ranking.« less

Effective Method of Purification of Betulin from Birch Bark: The Importance of Its Purity for Scientific and Medicinal Use

PubMed Central

Šiman, Pavel; Filipová, Alžběta; Tichá, Alena; Niang, Mohamed; Bezrouk, Aleš; Havelek, Radim

2016-01-01

A new and relatively simple method for purification of betulin from birch bark extract was developed in this study. Its five purification steps are based on the differential solubility of extract components in various solvents and their crystallization and/or precipitation, on their affinity for Ca(OH)2 in ethanol, and on the affinity of some impurities for silica gel in chloroform. In addition, all used solvents can be simply recycled. Betulin of more than 99% purity can be prepared by this method with minimal costs. Various observations including crystallization of betulin, changes in crystals during heating, and attempt of localization of betulin in outer birch bark are also described in this work. The original extract, fraction without betulinic acid and lupeol, amorphous fraction of pure betulin, final crystalline fraction of pure betulin and commercial betulin as a standard were employed to determine the antiproliferative/cytotoxic effect. We used WST-1 tetrazolium-based assays with triple negative breast cancer cell line BT-549. The decrease in cell survival showed clear relationship with the purity of the samples, being most pronounced using our final product of pure crystalline betulin. WST-1 proliferation/cytotoxicity test using triple negative breast cancer cell line BT-549 clearly showed the importance of purity of betulin for biological experiments and, apparently, for its medicinal use. PMID:27152419

The Role of Alveolar Epithelium in Radiation-Induced Lung Injury

PubMed Central

Almeida, Celine; Nagarajan, Devipriya; Tian, Jian; Leal, Sofia Walder; Wheeler, Kenneth; Munley, Michael; Blackstock, William; Zhao, Weiling

2013-01-01

Pneumonitis and fibrosis are major lung complications of irradiating thoracic malignancies. In the current study, we determined the effect of thoracic irradiation on the lungs of FVB/N mice. Survival data showed a dose-dependent increase in morbidity following thoracic irradiation with single (11–13 Gy) and fractionated doses (24–36 Gy) of 137Cs γ-rays. Histological examination showed a thickening of vessel walls, accumulation of inflammatory cells, collagen deposition, and regional fibrosis in the lungs 14 weeks after a single 12 Gy dose and a fractionated 30 Gy dose; this damage was also seen 5 months after a fractionated 24 Gy dose. After both single and fractionated doses, i] aquaporin-5 was markedly decreased, ii] E-cadherin was reduced and iii] prosurfactant Protein C (pro-SP-c), the number of pro-SP-c+ cells and vimentin expression were increased in the lungs. Immunofluorescence analysis revealed co-localization of pro-SP-c and α-smooth muscle actin in the alveoli after a single dose of 12 Gy. These data suggest that, i] the FVB/N mouse strain is sensitive to thoracic radiation ii] aquaporin-5, E-cadherin, and pro-SP-c may serve as sensitive indicators of radiation-induced lung injury; and iii] the epithelial-to-mesenchymal transition may play an important role in the development of radiation-induced lung fibrosis. PMID:23326473

Growth-suppressing and algicidal properties of an extract from Arundo donax, an invasive riparian plant, against Prymnesium parvum, an invasive harmful alga

USGS Publications Warehouse

Patino, Reynaldo; Rashel, Rakib H.; Rubio, Amede; Longing, Scott

2018-01-01

This study examined the ability of acidic and neutral/alkaline fractions of a methanolic extract from giant reed (Arundo donax) and of two of its constituents, gramine and skatole, to inhibit growth of the ichthyotoxic golden alga (Prymnesium parvum) in batch culture. For this study, growth suppression was defined as inhibition of maximum cell density, algicidal activity as early occurrence of negative growth, and algistatic activity as lack of net growth. The acidic fraction did not affect algal growth. The neutral/alkaline fraction showed growth-suppressing and algicidal activities but no signs of algistatic activity – namely, cells in cultures surviving a partial-algicidal exposure concentration (causing transient negative growth) were later able to initiate positive growth but at higher concentrations, algicidal activity was full and irreversible. Gramine suppressed growth more effectively than skatole and at the highest concentration tested, gramine also showed partial-algicidal and algistatic activity. While the partial-algicidal activities of the neutral/alkaline fraction and of gramine were short-lived (≤6 days) and thus may share similar mechanisms, algistatic activity was unique to gramine and persisted for >3 weeks. Given gramine’s reported concentration in the neutral/alkaline fraction, its corresponding level of algicidal activity is much lower than the fraction’s suggesting the latter contains additional potent algicides. Inhibition of maximum cell density by all test compounds was associated with reductions in exponential growth rate, and in the case of the neutral/alkaline fraction and gramine also reductions in early (pre-exponential) growth. These results indicate that giant reed is a potential source of natural products to control golden alga blooms. Giant reed is an invasive species in North America, thus also providing incentive for research into strategies to couple management efforts for both species.

Persistence of chromosome aberrations in mice acutely exposed to 56Fe+26 ions.

PubMed

Tucker, James D; Marples, Brian; Ramsey, Marilyn J; Lutze-Mann, Louise H

2004-06-01

Space exploration has the potential to yield exciting and significant discoveries, but it also brings with it many risks for flight crews. Among the less well studied of these are health effects from space radiation, which includes the highly charged, energetic particles of elements with high atomic numbers that constitute the galactic cosmic rays. In this study, we demonstrated that 1 Gy iron ions acutely administered to mice in vivo resulted in highly complex chromosome damage. We found that all types of aberrations, including dicentrics as well as translocations, insertions and acentric fragments, disappear rapidly with time after exposure, probably as a result of the death of heavily damaged cells, i.e. cells with multiple and/or complex aberrations. In addition, numerous cells have apparently simple exchanges as their only aberrations, and these cells appear to survive longer than heavily damaged cells. Eight weeks after exposure, the frequency of cells showing cytogenetic damage was reduced to less than 20% of the levels evident at 1 week, with little further decline apparent over an additional 8 weeks. These results indicate that exposure to 1 Gy iron ions produces heavily damaged cells, a small fraction of which appear to be capable of surviving for relatively long periods. The health effects of exposure to high-LET radiation in humans on prolonged space flights should remain a matter of concern.

A Hexane Fraction of Guava Leaves (Psidium guajava L.) Induces Anticancer Activity by Suppressing AKT/Mammalian Target of Rapamycin/Ribosomal p70 S6 Kinase in Human Prostate Cancer Cells

PubMed Central

Ryu, Nae Hyung; Park, Kyung-Ran; Kim, Sung-Moo; Yun, Hyung-Mun; Nam, Dongwoo; Lee, Seok-Geun; Jang, Hyeung-Jin; Ahn, Kyoo Seok; Kim, Sung-Hoon; Shim, Bum Sang; Choi, Seung-Hoon; Mosaddik, Ashik

2012-01-01

Abstract This study was carried out to evaluate the anticancer effects of guava leaf extracts and its fractions. The chemical compositions of the active extracts were also determined. In the present study, we set out to determine whether the anticancer effects of guava leaves are linked with their ability to suppress constitutive AKT/mammalian target of rapamycin (mTOR)/ribosomal p70 S6 kinase (S6K1) and mitogen-activated protein kinase (MAPK) activation pathways in human prostate cancer cells. We found that guava leaf hexane fraction (GHF) was the most potent inducer of cytotoxic and apoptotic effects in PC-3 cells. The molecular mechanism or mechanisms of GHF apoptotic potential were correlated with the suppression of AKT/mTOR/S6K1 and MAPK signaling pathways. This effect of GHF correlated with down-regulation of various proteins that mediate cell proliferation, cell survival, metastasis, and angiogenesis. Analysis of GHF by gas chromatography and gas chromatography–mass spectrometry tentatively identified 60 compounds, including β-eudesmol (11.98%), α-copaene (7.97%), phytol (7.95%), α-patchoulene (3.76%), β-caryophyllene oxide (CPO) (3.63%), caryophylla-3(15),7(14)-dien-6-ol (2.68%), (E)-methyl isoeugenol (1.90%), α-terpineol (1.76%), and octadecane (1.23%). Besides GHF, CPO, but not phytol, also inhibited the AKT/mTOR/S6K1 signaling pathway and induced apoptosis in prostate cancer cells. Overall, these findings suggest that guava leaves can interfere with multiple signaling cascades linked with tumorigenesis and provide a source of potential therapeutic compounds for both the prevention and treatment of cancer. PMID:22280146

A hexane fraction of guava Leaves (Psidium guajava L.) induces anticancer activity by suppressing AKT/mammalian target of rapamycin/ribosomal p70 S6 kinase in human prostate cancer cells.

PubMed

Ryu, Nae Hyung; Park, Kyung-Ran; Kim, Sung-Moo; Yun, Hyung-Mun; Nam, Dongwoo; Lee, Seok-Geun; Jang, Hyeung-Jin; Ahn, Kyoo Seok; Kim, Sung-Hoon; Shim, Bum Sang; Choi, Seung-Hoon; Mosaddik, Ashik; Cho, Somi K; Ahn, Kwang Seok

2012-03-01

This study was carried out to evaluate the anticancer effects of guava leaf extracts and its fractions. The chemical compositions of the active extracts were also determined. In the present study, we set out to determine whether the anticancer effects of guava leaves are linked with their ability to suppress constitutive AKT/mammalian target of rapamycin (mTOR)/ribosomal p70 S6 kinase (S6K1) and mitogen-activated protein kinase (MAPK) activation pathways in human prostate cancer cells. We found that guava leaf hexane fraction (GHF) was the most potent inducer of cytotoxic and apoptotic effects in PC-3 cells. The molecular mechanism or mechanisms of GHF apoptotic potential were correlated with the suppression of AKT/mTOR/S6K1 and MAPK signaling pathways. This effect of GHF correlated with down-regulation of various proteins that mediate cell proliferation, cell survival, metastasis, and angiogenesis. Analysis of GHF by gas chromatography and gas chromatography-mass spectrometry tentatively identified 60 compounds, including β-eudesmol (11.98%), α-copaene (7.97%), phytol (7.95%), α-patchoulene (3.76%), β-caryophyllene oxide (CPO) (3.63%), caryophylla-3(15),7(14)-dien-6-ol (2.68%), (E)-methyl isoeugenol (1.90%), α-terpineol (1.76%), and octadecane (1.23%). Besides GHF, CPO, but not phytol, also inhibited the AKT/mTOR/S6K1 signaling pathway and induced apoptosis in prostate cancer cells. Overall, these findings suggest that guava leaves can interfere with multiple signaling cascades linked with tumorigenesis and provide a source of potential therapeutic compounds for both the prevention and treatment of cancer.

Mathematical modelling of radiotherapy strategies for early breast cancer.

PubMed

Enderling, Heiko; Anderson, Alexander R A; Chaplain, Mark A J; Munro, Alastair J; Vaidya, Jayant S

2006-07-07

Targeted intraoperative radiotherapy (Targit) is a new concept of partial breast irradiation where single fraction radiotherapy is delivered directly to the tumour bed. Apart from logistic advantages, this strategy minimizes the risk of missing the tumour bed and avoids delay between surgery and radiotherapy. It is presently being compared with the standard fractionated external beam radiotherapy (EBRT) in randomized trials. In this paper we present a mathematical model for the growth and invasion of a solid tumour into a domain of tissue (in this case breast tissue), and then a model for surgery and radiation treatment of this tumour. We use the established linear-quadratic (LQ) model to compute the survival probabilities for both tumour cells and irradiated breast tissue and then simulate the effects of conventional EBRT and Targit. True local recurrence of the tumour could arise either from stray tumour cells, or the tumour bed that harbours morphologically normal cells having a predisposition to genetic changes, such as a loss of heterozygosity (LOH) in genes that are crucial for tumourigenesis, e.g. tumour suppressor genes (TSGs). Our mathematical model predicts that the single high dose of radiotherapy delivered by Targit would result in eliminating all these sources of recurrence, whereas the fractionated EBRT would eliminate stray tumour cells, but allow (by virtue of its very schedule) the cells with LOH in TSGs or cell-cycle checkpoint genes to pass on low-dose radiation-induced DNA damage and consequently mutations that may favour the development of a new tumour. The mathematical model presented here is an initial attempt to model a biologically complex phenomenon that has until now received little attention in the literature and provides a 'proof of principle' that it is possible to produce clinically testable hypotheses on the effects of different approaches of radiotherapy for breast cancer.

Evaluation of radiotherapy after incomplete surgery in patients with carcinoma of the maxillary sinus

DOE Office of Scientific and Technical Information (OSTI.GOV)

Korzeniowski, S.; Reinfuss, M.; Skolyszewski, J.

1985-03-01

The retrospective analysis of 57 patients with cancer of the maxillary antrum irradiated after incomplete surgery was performed is described. The majority of patients had very advanced disease (54% T4 tumors). In 18 patients partial resection of maxillary antrum was performed: 39 patients underwent total maxillectomy. In 35 patients macroscopic residual tumor (MRT) was present after surgery. All patients were irradiated postoperatively with /sup 60/Co teletherapy and received a dose of 60 Gy in 20-30 fractions over 4-6 weeks. Five year symptom-free survival in the whole group was 35%. An analysis of pattern of relapses indicates that histology should bemore » regarded as an important factor of management. In keratinizing squamous cell cancer, local control remains the main problem. In patients with nonkeratinizing squamous cell cancer, both local and regional control is important and elective irradiation of neck nodes may be of value. In patients with undifferentiated cancer, distant metastases appear to have the greatest impact on survival.« less

External-beam Co-60 radiotherapy for canine nasal tumors: a comparison of survival by treatment protocol.

PubMed

Yoon, J H; Feeney, D A; Jessen, C R; Walter, P A

2008-02-01

A retrospective analysis of survival times in dogs with intranasal tumors was performed comparing those treated using hypofractionated or full course Co-60 radiotherapy protocols alone or with surgical adjuvant therapy and those receiving no radiation treatment. One hundred thirty-nine dogs presented to the University of Minnesota Veterinary Medical Center for treatment of histologically-confirmed nasal neoplasia between July 1983 and October 2001 met the criteria for review. Statistically analyzed parameters included age at diagnosis, tumor histologic classification, fractionation schedule (number of treatments, and number of treatment days/week) (classified as hypofractionated if 2 or less treatments/week); calculated minimum tumor dose/fraction; calculated total minimum tumor dose (classified as hypofractionated if less than 37 Gy in six or fewer fractions); number of radiotherapy portals, a treatment gap of more than 7 days in a full course (3-5 treatments/week, 3-3.5 week treatment time) radiotherapy protocol, the influence of eye shields on survival following single portal DV fields, the survey radiographic extent of the disease, and the presence or absence of cytoreductive surgery. There was a significant relationship only between protocols using 3 or more treatments/week and at least 37 Gy cumulative minimum tumor dose and survival. However, there was no significant relationship between either total minimum tumor dose or dose/fraction and survival and there were no significant relationships between survival and any of the other variables analyzed including tumor histologic type.

Pharmacological doses of daily ascorbate protect tumors from radiation damage after a single dose of radiation in an intracranial mouse glioma model.

PubMed

Grasso, Carole; Fabre, Marie-Sophie; Collis, Sarah V; Castro, M Leticia; Field, Cameron S; Schleich, Nanette; McConnell, Melanie J; Herst, Patries M

2014-01-01

Pharmacological ascorbate is currently used as an anti-cancer treatment, potentially in combination with radiation therapy, by integrative medicine practitioners. In the acidic, metal-rich tumor environment, ascorbate acts as a pro-oxidant, with a mode of action similar to that of ionizing radiation; both treatments kill cells predominantly by free radical-mediated DNA damage. The brain tumor, glioblastoma multiforme (GBM), is very resistant to radiation; radiosensitizing GBM cells will improve survival of GBM patients. Here, we demonstrate that a single fraction (6 Gy) of radiation combined with a 1 h exposure to ascorbate (5 mM) sensitized murine glioma GL261 cells to radiation in survival and colony-forming assays in vitro. In addition, we report the effect of a single fraction (4.5 Gy) of whole brain radiation combined with daily intraperitoneal injections of ascorbate (1 mg/kg) in an intracranial GL261 glioma mouse model. Tumor-bearing C57BL/6 mice were divided into four groups: one group received a single dose of 4.5 Gy to the brain 8 days after tumor implantation, a second group received daily intraperitoneal injections of ascorbate (day 8-45) after implantation, a third group received both treatments and a fourth control group received no treatment. While radiation delayed tumor progression, intraperitoneal ascorbate alone had no effect on tumor progression. Tumor progression was faster in tumor-bearing mice treated with radiation and daily ascorbate than in those treated with radiation alone. Histological analysis showed less necrosis in tumors treated with both radiation and ascorbate, consistent with a radio-protective effect of ascorbate in vivo. Discrepancies between our in vitro and in vivo results may be explained by differences in the tumor microenvironment, which determines whether ascorbate remains outside the cell, acting as a pro-oxidant, or whether it enters the cells and acts as an anti-oxidant.

The use of recursive partitioning analysis grouping in patients with brain metastases from non-small-cell lung cancer.

PubMed

Gülbaş, Hülya; Erkal, Haldun Sükrü; Serin, Meltem

2006-04-01

This study evaluates the use of recursive partitioning analysis (RPA) grouping in an attempt to predict the survival probabilities in patients with brain metastases from non-small-cell lung cancer (NSCLC). Seventy-two patients with brain metastases from NSCLC treated with radiation therapy were included in the study. Sixty-three patients were male and nine patients were female. Their median age was 57 years and their median Karnofsky performance status was 70. At the time of brain metastases, there was no evidence of the intrathoracic disease in 27 patients and the extrathoracic disease was limited to the intracranial disease in 42 patients. In accordance with RPA grouping, 12 patients were in Group 1, 24 patients were in Group 2, and 36 patients were in Group 3. Radiation therapy was delivered to the whole brain at a dose of 30 Gy in 10 fractions in most of the patients. The median survival time was 7 months for Group 1, 5 months for Group 2 and 3 months for Group 3. The survival probability at 1 year was 50% for Group 1, 26% for Group 2 and 14% for Group 3. This study presents evidence supporting the use of RPA grouping in an attempt to predict the survival probabilities in patients with brain metastases from NSCLC.

Phosphatidylserine exposure on stored red blood cells as a parameter for donor-dependent variation in product quality.

PubMed

Dinkla, Sip; Peppelman, Malou; Van Der Raadt, Jori; Atsma, Femke; Novotný, Vera M J; Van Kraaij, Marian G J; Joosten, Irma; Bosman, Giel J C G M

2014-04-01

Exposure of phosphatidylserine on the outside of red blood cells contributes to recognition and removal of old and damaged cells. The fraction of phosphatidylserine-exposing red blood cells varies between donors, and increases in red blood cell concentrates during storage. The susceptibility of red blood cells to stress-induced phosphatidylserine exposure increases with storage. Phosphatidylserine exposure may, therefore, constitute a link between donor variation and the quality of red blood cell concentrates. In order to examine the relationship between storage parameters and donor characteristics, the percentage of phosphatidylserine-exposing red blood cells was measured in red blood cell concentrates during storage and in fresh red blood cells from blood bank donors. The percentage of phosphatidylserine-exposing red blood cells was compared with red blood cell susceptibility to osmotic stress-induced phosphatidylserine exposure in vitro, with the regular red blood cell concentrate quality parameters, and with the donor characteristics age, body mass index, haemoglobin level, gender and blood group. Phosphatidylserine exposure varies between donors, both on red blood cells freshly isolated from the blood, and on red blood cells in red blood cell concentrates. Phosphatidylserine exposure increases with storage time, and is correlated with stress-induced phosphatidylserine exposure. Increased phosphatidylserine exposure during storage was found to be associated with haemolysis and vesicle concentration in red blood cell concentrates. The percentage of phosphatidylserine-exposing red blood cells showed a positive correlation with the plasma haemoglobin concentration of the donor. The fraction of phosphatidylserine-exposing red blood cells is a parameter of red blood cell integrity in red blood cell concentrates and may be an indicator of red blood cell survival after transfusion. Measurement of phosphatidylserine exposure may be useful in the selection of donors and red blood cell concentrates for specific groups of patients.

Adaptation and Preadaptation of Salmonella enterica to Bile

PubMed Central

Hernández, Sara B.; Cota, Ignacio; Ducret, Adrien; Aussel, Laurent; Casadesús, Josep

2012-01-01

Bile possesses antibacterial activity because bile salts disrupt membranes, denature proteins, and damage DNA. This study describes mechanisms employed by the bacterium Salmonella enterica to survive bile. Sublethal concentrations of the bile salt sodium deoxycholate (DOC) adapt Salmonella to survive lethal concentrations of bile. Adaptation seems to be associated to multiple changes in gene expression, which include upregulation of the RpoS-dependent general stress response and other stress responses. The crucial role of the general stress response in adaptation to bile is supported by the observation that RpoS− mutants are bile-sensitive. While adaptation to bile involves a response by the bacterial population, individual cells can become bile-resistant without adaptation: plating of a non-adapted S. enterica culture on medium containing a lethal concentration of bile yields bile-resistant colonies at frequencies between 10−6 and 10−7 per cell and generation. Fluctuation analysis indicates that such colonies derive from bile-resistant cells present in the previous culture. A fraction of such isolates are stable, indicating that bile resistance can be acquired by mutation. Full genome sequencing of bile-resistant mutants shows that alteration of the lipopolysaccharide transport machinery is a frequent cause of mutational bile resistance. However, selection on lethal concentrations of bile also provides bile-resistant isolates that are not mutants. We propose that such isolates derive from rare cells whose physiological state permitted survival upon encountering bile. This view is supported by single cell analysis of gene expression using a microscope fluidic system: batch cultures of Salmonella contain cells that activate stress response genes in the absence of DOC. This phenomenon underscores the existence of phenotypic heterogeneity in clonal populations of bacteria and may illustrate the adaptive value of gene expression fluctuations. PMID:22275872

Glucose starvation impairs DNA repair in tumour cells selectively by blocking histone acetylation.

PubMed

Ampferl, Rena; Rodemann, Hans Peter; Mayer, Claus; Höfling, Tobias Tim Alexander; Dittmann, Klaus

2018-03-01

Tumour cells are characterized by aerobic glycolysis and thus have high glucose consumption. Because repairing radiation-induced DNA damage is an energy-demanding process, we hypothesized that glucose starvation combined with radiotherapy could be an effective strategy to selectively target tumour cells. We glucose-starved tumour cells (A549, FaDu) in vitro and analysed their radiation-induced cell responses compared to normal fibroblasts (HSF7). Irradiation depleted intracellular ATP levels preferentially in cancer cells. Consequently, glucose starvation impaired DNA double-strand break (DSB) repair and radiosensitized confluent tumour cells but not normal fibroblasts. In proliferating tumour cells glucose starvation resulted in a reduction of proliferation, but failed to radiosensitize cells. Glucose supply was indispensable during the late DSB repair in confluent tumour cells starting approximately 13 h after irradiation, and glucose starvation inhibited radiation-induced histone acetylation, which is essential for chromatin relaxation. Sirtinol - an inhibitor of histone deacetylases - reverted the effects of glucose depletion on histone acetylation and DNA DSB repair in tumour cells. Furthermore, a glucose concentration of 2.8 mmol/L was sufficient to impair DSB repair in tumour cells and reduced their clonogenic survival under a fractionated irradiation regimen. In resting tumour cells, glucose starvation combined with irradiation resulted in the impairment of late DSB repair and the reduction of clonogenic survival, which was associated with disrupted radiation-induced histone acetylation. However, in normal cells, DNA repair and radiosensitivity were not affected by glucose depletion. Copyright © 2017 Elsevier B.V. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, K

Purpose: Most prostate cancers are slow-growing diseases but normally require much higher doses (80Gy) with conventional fractionation radiotherapy, comparing to other more aggressive cancers. This study is to disclose the radiobiological basis of this discrepancy by proposing the concept of prostate cancer stem cells (CSCs) and examining their specific irradiation responses. Methods: There are overwhelming evidences that CSC may keep their stemness, e.g. the competency of cell differentiation, in hypoxic microenvironments and hence become radiation resistive, though the probability is tiny for aggressiveness cancers. Tumor hypoxia used to be considered as an independent reason for poor treatment outcomes, and recentmore » evidences showed that even prostate cancers were also hypoxic though they are very slow-growing. In addition, to achieve comparable outcomes to other much more aggressive cancers, much higher doses (rather than lower doses) are always needed for prostate cancers, regardless of its non-aggressiveness. All these abnormal facts can only be possibly interpreted by the irradiation responses characteristics of prostate CSCs. Results: Both normal cancer cells (NCCs) and CSCs exiting in tumors, in which NCCs are mainly for symptoms whereas killing all CSCs achieves disease-free. Since prostate cancers are slow-growing, the hypoxia in prostate cancers cannot possibly from NCCs, thus it is caused by hypoxic CSCs. However, single hypoxic cell cannot be imaged due to limitation of imaging techniques, unless a large group of hypoxic cells exist together, thus most of CSCs in prostate cancers are virtually hypoxic, i.e. not in working mode because CSCs in proliferating mode have to be normoxic, and this explains why prostate cancers are unaggressive. Conclusion: The fractional dose in conventional radiotherapy (∼2Gy) could only kill NCCs and CSCs in proliferating modes, whereas most CSCs survived fractional treatments since they were hypoxic, thus to eliminate all CSCs and achieve disease-free, much more fractionations are needed.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mendel, K; Miller, R; Murley, J

Purpose: To assess the effect of pre-treatment Magnetic Resonance Imaging (MRI) on cell survival following orthovoltage radiation therapy. Methods: This in vitro study examined the survival of FSa cells (extracted from methylcholanthrene-induced fibrosarcoma in the flank of a C3H female mouse) and SA-NH cells (derived from a spontaneously arising murine sarcoma tumor) having undergone an MRI scan prior to radiation exposure. Cell cultures were kept at 37 C, in a humidified environment with 5% CO2, and were grown to confluence prior to the start of the experiment. Each cell culture underwent two, 25 minute MRIs spaced 24 hours apart usingmore » a standard brain imaging protocol. The cultures were exposed to a 2 Gy dose of radiation beginning 15 minutes after the end of each MRI scan. Irradiations were performed by a Philips RT250 X-ray generator at 250 kVp and 15 mA. All MR imaging was performed on a 1.5 T Philips Achieva scanner using a head and neck vasculature coil. Results: Cells given an MRI scan prior to radiation exhibited an increase in mean surviving fraction of 10.8% and 9.6% in FSa and SA-NH cells, respectively. The difference was found to be statistically significant in both cell types by a student two-tailed t test with P = 0.011 and P < 0.001 for FSa and SA-NH, respectively. Conclusion: MRI may cause an increase in radio-resistance in FSa and SA-NH cells. If this biological effect is found to be consistent across other cell types and voltage ranges, these results could help inform treatment planning by improving our understanding of the joint effects of MRI and ionizing radiation. This work was supported in part under NIH grant numbers T32 EB002103, NCI R01-CA 132998, DOE Low Dose Program/Project Grant DE-413 SC0001271. DJ Grdina is a paid consultant to Pinnacle Biologics. DJ Grdina and JS Murley are minority equity partners in Pinnacle Oncology LLC.« less

Inosine Released from Dying or Dead Cells Stimulates Cell Proliferation via Adenosine Receptors.

PubMed

Chen, Jin; Chaurio, Ricardo A; Maueröder, Christian; Derer, Anja; Rauh, Manfred; Kost, Andriy; Liu, Yi; Mo, Xianming; Hueber, Axel; Bilyy, Rostyslav; Herrmann, Martin; Zhao, Yi; Muñoz, Luis E

2017-01-01

Many antitumor therapies induce apoptotic cell death in order to cause tumor regression. Paradoxically, apoptotic cells are also known to promote wound healing, cell proliferation, and tumor cell repopulation in multicellular organisms. We aimed to characterize the nature of the regenerative signals concentrated in the micromilieu of dead and dying cells. Cultures of viable melanoma B16F10 cells, mouse fibroblasts, and primary human fibroblast-like synoviocytes (FLS) in the presence of dead and dying cells, their supernatants (SNs), or purified agonists and antagonists were used to evaluate the stimulation of proliferation. Viable cell quantification was performed by either flow cytometry of harvested cells or by crystal violet staining of adherent cells. High-performance liquid chromatography and liquid chromatography coupled with mass spectrometry of cell SNs were deployed to identify the nature of growth-promoting factors. Coimplantation of living cells in the presence of SNs collected from dead and dying cells and specific agonists was used to evaluate tumor growth in vivo . The stimulation of proliferation of few surviving cells by bystander dead cells was confirmed for melanoma cells, mouse fibroblasts, and primary FLS. We found that small soluble molecules present in the protein-free fraction of SNs of dead and dying cells were responsible for the promotion of proliferation. The nucleoside inosine released by dead and dying cells acting via adenosine receptors was identified as putative inducer of proliferation of surviving tumor cells after irradiation and heat treatment. Inosine released by dead and dying cells mediates tumor cell proliferation via purinergic receptors. Therapeutic strategies surmounting this pathway may help to reduce the rate of recurrence after radio- and chemotherapy.

Improved survival time: what can survival cure models tell us about population-based survival improvements in late-stage colorectal, ovarian, and testicular cancer?

PubMed

Huang, Lan; Cronin, Kathleen A; Johnson, Karen A; Mariotto, Angela B; Feuer, Eric J

2008-05-15

The objective of the current study was to investigate the long-term impact of treatment advances on the survival of patients with late-stage ovarian, colorectal (American Joint Committee on Cancer stage III, men), and testicular cancers by estimating the increase in the percentage cured from their disease and the change in survival time of uncured patients. Cause-specific survival data from 1973 to 2000 were obtained from the Surveillance, Epidemiology, and End Results Program. Survival cure models were fit and were used to estimate the gain in life expectancy (GLE) attributed to an increase in the fraction of cured patients and to prolonged survival among noncured patients. Treatment improvement for ovarian cancer resulted in a total GLE of 2 years, and 80% of that GLE was because of an extension of survival time in uncured patients (from 0.9 years to 2.1 years) rather than an increased cure fraction (from 12% to 14%). In contrast, the cure rate rose from 29% to 47% for colorectal cancer, representing 82% of a 2.8-year GLE, and from 23% to 81% for testicular cancer, representing 100% of a 24-year GLE. The current results suggested that treatment benefits for testicular and colorectal cancer in men with late-stage disease primarily are the result of increases in cure fraction, whereas survival gains for ovarian cancer occur despite persisting disease. Cure models, in combination with population-level data, provide insight into how treatment advances are changing survival and ultimately impacting mortality. Survival patterns reflect the underlying biology of response to cancer treatment and suggest promising directions for future research.

Venetoclax Is Effective in Small-Cell Lung Cancers with High BCL-2 Expression.

PubMed

Lochmann, Timothy L; Floros, Konstantinos V; Naseri, Mitra; Powell, Krista M; Cook, Wade; March, Ryan J; Stein, Giovanna T; Greninger, Patricia; Maves, Yuki Kato; Saunders, Laura R; Dylla, Scott J; Costa, Carlotta; Boikos, Sosipatros A; Leverson, Joel D; Souers, Andrew J; Krystal, Geoffrey W; Harada, Hisashi; Benes, Cyril H; Faber, Anthony C

2018-01-15

Purpose: Small-cell lung cancer (SCLC) is an often-fatal neuroendocrine carcinoma usually presenting as extensive disease, carrying a 3% 5-year survival. Despite notable advances in SCLC genomics, new therapies remain elusive, largely due to a lack of druggable targets. Experimental Design: We used a high-throughput drug screen to identify a venetoclax-sensitive SCLC subpopulation and validated the findings with multiple patient-derived xenografts of SCLC. Results: Our drug screen consisting of a very large collection of cell lines demonstrated that venetoclax, an FDA-approved BCL-2 inhibitor, was found to be active in a substantial fraction of SCLC cell lines. Venetoclax induced BIM-dependent apoptosis in vitro and blocked tumor growth and induced tumor regressions in mice bearing high BCL-2-expressing SCLC tumors in vivo BCL-2 expression was a predictive biomarker for sensitivity in SCLC cell lines and was highly expressed in a subset of SCLC cell lines and tumors, suggesting that a substantial fraction of patients with SCLC could benefit from venetoclax. Mechanistically, we uncover a novel role for gene methylation that helped discriminate high BCL-2-expressing SCLCs. Conclusions: Altogether, our findings identify venetoclax as a promising new therapy for high BCL-2-expressing SCLCs. Clin Cancer Res; 24(2); 360-9. ©2017 AACR . ©2017 American Association for Cancer Research.

Long term outcomes of cardiac transplant for immunoglobulin light chain amyloidosis: The Mayo Clinic experience

PubMed Central

Grogan, Martha; Gertz, Morie; McCurdy, Arleigh; Roeker, Lindsey; Kyle, Robert; Kushwaha, Sudhir; Daly, Richard; Dearani, Joseph; Rodeheffer, Richard; Frantz, Robert; Lacy, Martha; Hayman, Suzanne; McGregor, Christopher; Edwards, Brooks; Dispenzieri, Angela

2016-01-01

AIM: To determine the outcome of orthotopic heart transplantation (OHT) in immunoglobulin light chain (AL) amyloidosis. METHODS: The medical records of patients with AL who underwent orthotopic heart transplantation at the Mayo Clinic in Rochester Minnesota from 1992 to 2011 were reviewed. Patients met at least one of the following at: New York Heart Association class IV heart failure, ventricular thickness > 15 mm, ejection fraction < 40%. Selection guidelines for heart transplant included age < 60 years, absence of multiple myeloma and significant extra-cardiac organ involvement. Baseline characteristics including age, gender, organ involvement, and New York Heart Association functional class were recorded. Laboratory data, waiting time until heart transplant, and type of treatment of the underlying plasma cell disorder were recorded. Survival from the time of OHT was calculated using Kaplan-Meier survival curves. Survival of patients undergoing OHT for AL was compared to that of non-amyloid patients undergoing OHT during the same time period. RESULTS: Twenty-three patients (median age 53 years) with AL received OHT. There were no deaths in the immediate perioperative period. Twenty patients have died post OHT. For the entire cohort, the median overall survival was 3.5 years (95%CI: 1.2, 8.2 years). The 1-year survival post OHT was 77%, the 2-year survival 65%, and the 5-year survival 43%. The 5-year survival for non-amyloid patients undergoing OHT during the same era was 85%. Progressive amyloidosis contributed to death in twelve patients. Of those without evidence of progressive amyloidosis, the cause of death included complications of autologous hematopoietic stem cell transplantation for 3 patients, post-transplant lymphoproliferative disorder for 2 patients; and for the remaining one death was related to each of the following causes: acute rejection; cardiac vasculopathy; metastatic melanoma; myelodysplastic syndrome; and unknown. Eight patients had rejection at a median of 1.8 mo post OHT (range 0.4 to 4.9 mo); only one patient died of rejection. Median survival of seven patients who achieved a complete hematologic response to either chemotherapy or autologous hematopoietic stem cell transplantation was 10.8 years. CONCLUSION: Our data demonstrate that long term survival after heart transplant is feasible in AL patients with limited extra-cardiac involvement who achieve complete hematologic response. PMID:27358783

Application of a Non-Mixture Cure Rate Model for Analyzing Survival of Patients with Breast Cancer.

PubMed

Baghestani, Ahmad Reza; Moghaddam, Sahar Saeedi; Majd, Hamid Alavi; Akbari, Mohammad Esmaeil; Nafissi, Nahid; Gohari, Kimiya

2015-01-01

As a result of significant progress made in treatment of many types of cancers during the last few decades, there have been an increased number of patients who do not experience mortality. We refer to these observations as cure or immune and models for survival data which include cure fraction are known as cure rate models or long-term survival models. In this study we used the data collected from 438 female patients with breast cancer registered in the Cancer Research Center in Shahid Beheshti University of Medical Sciences, Tehran, Iran. The patients had been diagnosed from 1992 to 2012 and were followed up until October 2014. We had to exclude some because of incomplete information. Phone calls were made to confirm whether the patients were still alive or not. Deaths due to breast cancer were regarded as failure. To identify clinical, pathological, and biological characteristics of patients that might have had an effect on survival of the patients we used a non-mixture cure rate model; in addition, a Weibull distribution was proposed for the survival time. Analyses were performed using STATA version 14. The significance level was set at P ≤ 0.05. A total of 75 patients (17.1%) died due to breast cancer during the study, up to the last follow-up. Numbers of metastatic lymph nodes and histologic grade were significant factors. The cure fraction was estimated to be 58%. When a cure fraction is not available, the analysis will be changed to standard approaches of survival analysis; however when the data indicate that the cure fraction is available, we suggest analysis of survival data via cure models.

Myocilin Regulates Cell Proliferation and Survival*

PubMed Central

Joe, Myung Kuk; Kwon, Heung Sun; Cojocaru, Radu; Tomarev, Stanislav I.

2014-01-01

Myocilin, a causative gene for open angle glaucoma, encodes a secreted glycoprotein with poorly understood functions. To gain insight into its functions, we produced a stably transfected HEK293 cell line expressing myocilin under an inducible promoter and compared gene expression profiles between myocilin-expressing and vector control cell lines by a microarray analysis. A significant fraction of differentially expressed genes in myocilin-expressing cells was associated with cell growth and cell death, suggesting that myocilin may have a role in the regulation of cell growth and survival. Increased proliferation of myocilin-expressing cells was demonstrated by the WST-1 proliferation assay, direct cell counting, and immunostaining with antibodies against Ki-67, a cellular proliferation marker. Myocilin-containing conditioned medium also increased proliferation of unmodified HEK293 cells. Myocilin-expressing cells were more resistant to serum starvation-induced apoptosis than control cells. TUNEL-positive apoptotic cells were dramatically decreased, and two apoptotic marker proteins, cleaved caspase 7 and cleaved poly(ADP-ribose) polymerase, were significantly reduced in myocilin-expressing cells as compared with control cells under apoptotic conditions. In addition, myocilin-deficient mesenchymal stem cells exhibited reduced proliferation and enhanced susceptibility to serum starvation-induced apoptosis as compared with wild-type mesenchymal stem cells. Phosphorylation of ERK1/2 and its upstream kinases, c-Raf and MEK, was increased in myocilin-expressing cells compared with control cells. Elevated phosphorylation of ERK1/2 was also observed in the trabecular meshwork of transgenic mice expressing 6-fold higher levels of myocilin when compared with their wild-type littermates. These results suggest that myocilin promotes cell proliferation and resistance to apoptosis via the ERK1/2 MAPK signaling pathway. PMID:24563482

The myotoxic effect of bupivacaine and ropivacaine on myotubes in primary mouse cell culture and an immortalized cell line.

PubMed

Hofmann, Petra; Metterlein, Thomas; Bollwein, Gabriele; Gruber, Michael; Plank, Christoph; Graf, Bernhard M; Zink, Wolfgang

2013-09-01

The 2 local anesthetics (LAs) bupivacaine and ropivacaine have acute cytotoxic effects on different tissues. In this respect, LA-induced myotoxicity has been subject to various studies; however, the exact mechanisms are still not fully understood. Most in vitro studies use immortalized cell lines because of feasibility. Thus, establishing a primary cell line might result in more accurate results. In this study, we examined the effects of immortalization on bupivacaine- and ropivacaine-induced myotoxicity in vitro. An immortalized (N = 6) and a primary cell line (N = 8) of the same tissue and species were established, and differentiation in myotubes was induced. Cells were exposed to increasing concentrations of bupivacaine and ropivacaine for 1 or 2 hours, respectively. Twenty-four and 48 hours after treatment, the fractions of dead and vital cells were measured using flow cytometry. Significance was tested through 1-way analysis of variance with post hoc Dunnett T3 test. Medians of dataset pairs were compared by T test. In both cell lines, increasing concentrations of both LAs resulted in decreased cell survival (e.g., P < 0.001 for 5000 ppm bupivacaine, 1 or 2 hours of incubation, and 24 hours recovery in both cell lines). For the same LA concentrations, survival was significantly higher in the immortalized cell culture (e.g., P < 0.001 for 2500 ppm ropivacaine, 1 hour of incubation, and 24 hours recovery). In addition, equal concentrations of bupivacaine resulted in significantly fewer vital cells compared with ropivacaine (e.g., P = 0.032 for 2500 ppm ropivacaine, 1 hour of incubation, and 24 hours recovery). Two hours of incubation resulted in a significantly higher rate of dead cells compared with 1 hour of incubation (e.g., P = 0.004 for C2C12 cells, 2500 ppm bupivacaine, and 24 hours recovery). Primary skeletal muscle cells are more vulnerable to LAs than immortalized cells. The higher myotoxic potential of bupivacaine compared with ropivacaine in vivo can be reproduced in vitro. Incubation time has an influence on cell survival.

Behavior of Paramecium sp. in solutions containing Sr and Pb: Do Paramecium sp. alter chemical forms of those metals?

NASA Astrophysics Data System (ADS)

Kozai, Naofumi; Ohnuki, Toshihiko; Koka, Masahi; Satoh, Takahiro; Kamiya, Tomihiro

2011-10-01

The behavior of Paramecium sp. (Paramecium bursaria) in aqueous solutions containing Sr and Pb was investigated to determine the role of protozoa in the migration of radionuclides in the environment. Precultured living cells of P. bursaria were exposed to aqueous solutions containing 0.01 or 0.05 mM Sr or Pb at pH 7 for 24 h. For comparison, pre-killed cells were treated with the metal solutions in the same way. Two-dimensional elemental mappings of cells were obtained by micro-PIXE. Aquatic species of Sr and Pb were analyzed by size exclusion chromatography (SEC) coupled online to ultraviolet (UV) spectroscopy and inductivity coupled plasma mass spectroscopy (ICP-MS). The amounts of Sr adsorbed or taken up by the cells surviving for 24 h and adsorbed on pre-killed cells were below the detection limit. Cells of P. bursaria adsorbed or took up a fraction of Pb. The Pb adsorbed or taken up by the cells surviving for 24 h in the Pb solution was barely detectable, while the Pb adsorbed on pre-killed cells was clearly mappable. These findings suggest that living cells of P. bursaria have functions that reduce adsorption or uptake of Pb on the cells. Quantitative and SEC-UV-ICP-MS analyses of the Sr and Pb in aqueous phases showed no clear evidences that living cells of P. bursaria alter the chemical form of Sr or Pb remaining in the aqueous phases after the cell-solution contact.

LKB1 promotes cell survival by modulating TIF-IA-mediated pre-ribosomal RNA synthesis under uridine downregulated conditions

PubMed Central

Liu, Xiuju; Huang, Henry; Wilkinson, Scott C.; Zhong, Diansheng; Khuri, Fadlo R.; Fu, Haian; Marcus, Adam; He, Yulong; Zhou, Wei

2016-01-01

We analyzed the mechanism underlying 5-aminoimidazole-4-carboxamide riboside (AICAR) mediated apoptosis in LKB1-null non-small cell lung cancer (NSCLC) cells. Metabolic profile analysis revealed depletion of the intracellular pyrimidine pool after AICAR treatment, but uridine was the only nucleotide precursor capable of rescuing this apoptosis, suggesting the involvement of RNA metabolism. Because half of RNA transcription in cancer is for pre-ribosomal RNA (rRNA) synthesis, which is suppressed by over 90% after AICAR treatment, we evaluated the role of TIF-IA-mediated rRNA synthesis. While the depletion of TIF-IA by RNAi alone promoted apoptosis in LKB1-null cells, the overexpression of a wild-type or a S636A TIF-IA mutant, but not a S636D mutant, attenuated AICAR-induced apoptosis. In LKB1-null H157 cells, pre-rRNA synthesis was not suppressed by AICAR when wild-type LKB1 was present, and cellular fractionation analysis indicated that TIF-IA quickly accumulated in the nucleus in the presence of a wild-type LKB1 but not a kinase-dead mutant. Furthermore, ectopic expression of LKB1 was capable of attenuating AICAR-induced death in AMPK-null cells. Because LKB1 promotes cell survival by modulating TIF-IA-mediated pre-rRNA synthesis, this discovery suggested that targeted depletion of uridine related metabolites may be exploited in the clinic to eliminate LKB1-null cancer cells. PMID:26506235

LKB1 promotes cell survival by modulating TIF-IA-mediated pre-ribosomal RNA synthesis under uridine downregulated conditions.

PubMed

Liu, Fakeng; Jin, Rui; Liu, Xiuju; Huang, Henry; Wilkinson, Scott C; Zhong, Diansheng; Khuri, Fadlo R; Fu, Haian; Marcus, Adam; He, Yulong; Zhou, Wei

2016-01-19

We analyzed the mechanism underlying 5-aminoimidazole-4-carboxamide riboside (AICAR) mediated apoptosis in LKB1-null non-small cell lung cancer (NSCLC) cells. Metabolic profile analysis revealed depletion of the intracellular pyrimidine pool after AICAR treatment, but uridine was the only nucleotide precursor capable of rescuing this apoptosis, suggesting the involvement of RNA metabolism. Because half of RNA transcription in cancer is for pre-ribosomal RNA (rRNA) synthesis, which is suppressed by over 90% after AICAR treatment, we evaluated the role of TIF-IA-mediated rRNA synthesis. While the depletion of TIF-IA by RNAi alone promoted apoptosis in LKB1-null cells, the overexpression of a wild-type or a S636A TIF-IA mutant, but not a S636D mutant, attenuated AICAR-induced apoptosis. In LKB1-null H157 cells, pre-rRNA synthesis was not suppressed by AICAR when wild-type LKB1 was present, and cellular fractionation analysis indicated that TIF-IA quickly accumulated in the nucleus in the presence of a wild-type LKB1 but not a kinase-dead mutant. Furthermore, ectopic expression of LKB1 was capable of attenuating AICAR-induced death in AMPK-null cells. Because LKB1 promotes cell survival by modulating TIF-IA-mediated pre-rRNA synthesis, this discovery suggested that targeted depletion of uridine related metabolites may be exploited in the clinic to eliminate LKB1-null cancer cells.

Semi-parametric regression model for survival data: graphical visualization with R

PubMed Central

2016-01-01

Cox proportional hazards model is a semi-parametric model that leaves its baseline hazard function unspecified. The rationale to use Cox proportional hazards model is that (I) the underlying form of hazard function is stringent and unrealistic, and (II) researchers are only interested in estimation of how the hazard changes with covariate (relative hazard). Cox regression model can be easily fit with coxph() function in survival package. Stratified Cox model may be used for covariate that violates the proportional hazards assumption. The relative importance of covariates in population can be examined with the rankhazard package in R. Hazard ratio curves for continuous covariates can be visualized using smoothHR package. This curve helps to better understand the effects that each continuous covariate has on the outcome. Population attributable fraction is a classic quantity in epidemiology to evaluate the impact of risk factor on the occurrence of event in the population. In survival analysis, the adjusted/unadjusted attributable fraction can be plotted against survival time to obtain attributable fraction function. PMID:28090517

Effects of carvedilol therapy in patients with heart failure with preserved ejection fraction - Results from the Croatian heart failure (CRO-HF) registry.

PubMed

Domagoj, Markovic; Branka, Jurcevic Zidar; Jelena, Macanovic; Davor, Milicic; Duska, Glavas

2018-04-17

According to recent guidelines, the best approach for treatment of heart failure patients with preserved ejection function is still not defined. The aim of this study was to investigate how carvedilol therapy influences the survival rate, ejection fraction and NYHA class in these patients. We conducted study on heart failure patients with preserved systolic function from the Croatian heart failure registry who were hospitalized in the period between 2005 and 2010. We enrolled patients with carvedilol listed as treatment on their discharge letters and patients who had been using carvedilol for at least 4 years, while for the control group we selected patients with no beta-blockers on their discharge letters (113 vs 204 respectively). The primary outcome was the overall survival rate and the secondary outcome was the change in ejection fraction of the left ventricle and NYHA class during the study. Patients in the carvedilol group had a higher overall survival rate compared to patients in the control group (chi-square=14.1, P<0.001). Patients in the carvedilol group in two measurements had a significantly higher ejection fraction compared to the control group (F=148.04, P<0.001). Also, patients in the carvedilol group showed improvement in NYHA class (chi-square=29.768, P<0.001). Long term carvedilol therapy appears to be associated with a higher overall survival rate, improvement in ejection fraction and NYHA class in heart failure patients with preserved ejection fraction. Copyright © 2018 Elsevier España, S.L.U. All rights reserved.

Number and Location of Positive Nodes, Postoperative Radiotherapy, and Survival After Esophagectomy With Three-Field Lymph Node Dissection for Thoracic Esophageal Squamous Cell Carcinoma

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen Junqiang; Pan Jianji, E-mail: panjianji@126.com; Zheng Xiongwei

2012-01-01

Purpose: To analyze influences of the number and location of positive lymph nodes and postoperative radiotherapy on survival for patients with thoracic esophageal squamous cell carcinoma (TE-SCC) treated with radical esophagectomy with three-field lymphadenectomy. Methods and Materials: A total of 945 patients underwent radical esophagectomy plus three-field lymph node dissection for node-positive TE-SCC at Fujian Provincial Tumor Hospital between January 1993 and March 2007. Five hundred ninety patients received surgery only (S group), and 355 patients received surgery, followed 3 to 4 weeks later by postoperative radiotherapy (S+R group) to a median total dose of 50 Gy in 25 fractions.more » We assessed potential associations among patient-, tumor-, and treatment-related factors and overall survival. Results: Five-year overall survival rates were 32.8% for the entire group, 29.6% for the S group, and 38.0% for the S+R group (p = 0.001 for S vs. S+R). Treatment with postoperative radiotherapy was particularly beneficial for patients with {>=}3 positive nodes and for those with metastasis in the upper (supraclavicular and upper mediastinal) region or both the upper and lower (mediastinal and abdominal) regions (p < 0.05). Postoperative radiotherapy was also associated with lower recurrence rates in the supraclavicular and upper and middle mediastinal regions (p < 0.05). Sex, primary tumor length, number of positive nodes, pathological T category, and postoperative radiotherapy were all independent predictors of survival. Conclusions: Postoperative radiotherapy was associated with better survival for patients with node-positive TE-SCC, particularly those with three or more positive nodes and positive nodes in the supraclavicular and superior mediastinal regions.« less

Solving the puzzle of yeast survival in ephemeral nectar systems: exponential growth is not enough.

PubMed

Hausmann, Sebastian L; Tietjen, Britta; Rillig, Matthias C

2017-12-01

Flower nectar is a sugar-rich ephemeral habitat for microorganisms. Nectar-borne yeasts are part of the microbial community and can affect pollination by changing nectar chemistry, attractiveness to pollinators or flower temperature if yeast population densities are high. Pollinators act as dispersal agents in this system; however, pollination events lead potentially to shrinking nectar yeast populations. We here examine how sufficiently high cell densities of nectar yeast can develop in a flower. In laboratory experiments, we determined the remaining fraction of nectar yeast cells after nectar removal, and used honeybees to determine the number of transmitted yeast cells from one flower to the next. The results of these experiments directly fed into a simulation model providing an insight into movement and colonization ecology of nectar yeasts. We found that cell densities only reached an ecologically relevant size for an intermediate pollination probability. Too few pollination events reduce yeast inoculation rate and too many reduce yeast population size strongly. In addition, nectar yeasts need a trait combination of at least an intermediate growth rate and an intermediate remaining fraction to compensate for highly frequent decimations. Our results can be used to predict nectar yeast dispersal, growth and consequently their ecological effects. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Anti-tuberculosis and cytotoxic evaluation of the seaweed Sargassum boveanum.

PubMed

Akbari, Vajihe; Zafari, Saeed; Yegdaneh, Afsaneh

2018-02-01

Marine seaweeds produce a variety of compounds with different biological activities, including antituberculosis and anticancer effects. The aim of this study was to investigate anti-tuberculosis activity of Sargassum boveanum ( S. boveanum ) and cytotoxicity of different fractions of this seaweed. S. boveanum was collected from Persian Gulf. The plant was extracted by maceration with methanol-ethyl acetate solvent. The extract was evaporated and partitioned by Kupchan method to yield hexane, tricholoroethane, chloroform, and butanol partitions. The anti-tuberculosis activity of the crude extract and toxicity of the fractions were investigated using green fluorescent protein reporter microplate assay and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay methods, respectively. The cell survivals of HeLa cell were decreased by increasing the concentration of the extracts. The IC 50 values of hexane, tricholoroethane, chloroform, and butanol partitions were 150.3 ± 23.10, 437.0 ± 147.3, 110.4 ± 33.67, and 1025.0 ± 15.20 μg/mL, respectively. The crude extract was not active against tuberculosis. This study reveals that different partitions of S. boveanum have cytotoxic activity against the cancer cell lines.

Clonogenic assay: adherent cells.

PubMed

Rafehi, Haloom; Orlowski, Christian; Georgiadis, George T; Ververis, Katherine; El-Osta, Assam; Karagiannis, Tom C

2011-03-13

The clonogenic (or colony forming) assay has been established for more than 50 years; the original paper describing the technique was published in 1956. Apart from documenting the method, the initial landmark study generated the first radiation-dose response curve for X-ray irradiated mammalian (HeLa) cells in culture. Basically, the clonogenic assay enables an assessment of the differences in reproductive viability (capacity of cells to produce progeny; i.e. a single cell to form a colony of 50 or more cells) between control untreated cells and cells that have undergone various treatments such as exposure to ionising radiation, various chemical compounds (e.g. cytotoxic agents) or in other cases genetic manipulation. The assay has become the most widely accepted technique in radiation biology and has been widely used for evaluating the radiation sensitivity of different cell lines. Further, the clonogenic assay is commonly used for monitoring the efficacy of radiation modifying compounds and for determining the effects of cytotoxic agents and other anti-cancer therapeutics on colony forming ability, in different cell lines. A typical clonogenic survival experiment using adherent cells lines involves three distinct components, 1) treatment of the cell monolayer in tissue culture flasks, 2) preparation of single cell suspensions and plating an appropriate number of cells in petri dishes and 3) fixing and staining colonies following a relevant incubation period, which could range from 1-3 weeks, depending on the cell line. Here we demonstrate the general procedure for performing the clonogenic assay with adherent cell lines with the use of an immortalized human keratinocyte cell line (FEP-1811). Also, our aims are to describe common features of clonogenic assays including calculation of the plating efficiency and survival fractions after exposure of cells to radiation, and to exemplify modification of radiation-response with the use of a natural antioxidant formulation.

Radiation sensitivity of Merkel cell carcinoma cell lines

DOE Office of Scientific and Technical Information (OSTI.GOV)

Leonard, J.H.; Ramsay, J.R.; Birrell, G.W.

1995-07-30

Merkel cell carcinoma (MCC), being a small cell carcinoma, would be expected to be sensitive to radiation. Clinical analysis of patients at our center, especially those with macroscopic disease, would suggest the response is quite variable. We have recently established a number of MCC cell lines from patients prior to radiotherapy, and for the first time are in a position to determine their sensitivity under controlled conditions. Some of the MCC lines grew as suspension cultures and could not be single cell cloned; therefore, it was not possible to use clonogenic survival for all cell lines. A tetrazolium based (MTT)more » assay was used for these lines, to estimate cell growth after {gamma} irradiation. Control experiments were conducted on lymphoblastoid cell lines (LCL) and the adherent MCC line, MCC13, to demonstrate that the two assays were comparable under the conditions used. We have examined cell lines from MCC, small cell lung cancer (SCLC), malignant melanomas, Epstein Barr virus (EBV) transformed lymphocytes (LCL), and skin fibroblasts for their sensitivity to {gamma} irradiation using both clonogenic cell survival and MTT assays. The results show that the tumor cell lines have a range of sensitivities, with melanoma being more resistant (surviving fraction at 2 Gy (SF2) 0.57 and 0.56) than the small cell carcinoma lines, MCC (SF2 range 0.21-0.45, mean SF2 0.30, n = 8) and SCLC (SF2 0.31). Fibroblasts were the most sensitive (SF2 0.13-0.20, mean 0.16, n = 5). The MTT assay, when compared to clonogenic assay for the MCC13 adherent line and the LCL, gave comparable results under the conditions used. Both assays gave a range of SF2 values for the MCC cell lines, suggesting that these cancers would give a heterogeneous response in vivo. The results with the two derivative clones of MCC14 (SF2 for MCC14/1 0.38, MCC14/2 0.45) would further suggest that some of them may develop resistance during clonogenic evolution. 25 refs., 3 figs., 1 tab.« less

Parasite-mediated upregulation of NK cell-derived gamma interferon protects against severe highly pathogenic H5N1 influenza virus infection.

PubMed

O'Brien, Kevin B; Schultz-Cherry, Stacey; Knoll, Laura J

2011-09-01

Outbreaks of influenza A viruses are associated with significant human morbidity worldwide. Given the increasing resistance to the available influenza drugs, new therapies for the treatment of influenza virus infection are needed. An alternative approach is to identify products that enhance a protective immune response. In these studies, we demonstrate that infecting mice with the Th1-inducing parasite Toxoplasma gondii prior to highly pathogenic avian H5N1 influenza virus infection led to decreased lung viral titers and enhanced survival. A noninfectious fraction of T. gondii soluble antigens (STAg) elicited an immune response similar to that elicited by live parasites, and administration of STAg 2 days after H5N1 influenza virus infection enhanced survival, lowered viral titers, and reduced clinical disease. STAg administration protected H5N1 virus-infected mice lacking lymphocytes, suggesting that while the adaptive immune response was not required for enhanced survival, it was necessary for STAg-mediated viral clearance. Mechanistically, we found that administration of STAg led to increased production of gamma interferon (IFN-γ) from natural killer (NK) cells, which were both necessary and sufficient for survival. Further, administration of exogenous IFN-γ alone enhanced survival from H5N1 influenza virus infection, although not to the same level as STAg treatment. These studies demonstrate that a noninfectious T. gondii extract enhances the protective immune response against severe H5N1 influenza virus infections even when a single dose is administered 2 days postinfection.

Conditional Switching of Vascular Endothelial Growth Factor (VEGF) Expression in Tumors: Induction of Endothelial Cell Shedding and Regression of Hemangioblastoma-Like Vessels by VEGF Withdrawal

NASA Astrophysics Data System (ADS)

Benjamin, Laura E.; Keshet, Eli

1997-08-01

We have recently shown that VEGF functions as a survival factor for newly formed vessels during developmental neovascularization, but is not required for maintenance of mature vessels. Reasoning that expanding tumors contain a significant fraction of newly formed and remodeling vessels, we examined whether abrupt withdrawal of VEGF will result in regression of preformed tumor vessels. Using a tetracycline-regulated VEGF expression system in xenografted C6 glioma cells, we showed that shutting off VEGF production leads to detachment of endothelial cells from the walls of preformed vessels and their subsequent death by apoptosis. Vascular collapse then leads to hemorrhages and extensive tumor necrosis. These results suggest that enforced withdrawal of vascular survival factors can be applied to target preformed tumor vasculature in established tumors. The system was also used to examine phenotypes resulting from over-expression of VEGF. When expression of the transfected VEGF cDNA was continuously ``on,'' tumors became hyper-vascularized with abnormally large vessels, presumably arising from excessive fusions. Tumors were significantly less necrotic, suggesting that necrosis in these tumors is the result of insufficient angiogenesis.

Thrombopoietin/MPL participates in initiating and maintaining RUNX1-ETO acute myeloid leukemia via PI3K/AKT signaling

PubMed Central

Pulikkan, John Anto; Madera, Dmitri; Xue, Liting; Bradley, Paul; Landrette, Sean Francis; Kuo, Ya-Huei; Abbas, Saman; Zhu, Lihua Julie; Valk, Peter

2012-01-01

Oncogenic mutations in components of cytokine signaling pathways elicit ligand-independent activation of downstream signaling, enhancing proliferation and survival in acute myeloid leukemia (AML). The myeloproliferative leukemia virus oncogene, MPL, a homodimeric receptor activated by thrombopoietin (THPO), is mutated in myeloproliferative disorders but rarely in AML. Here we show that wild-type MPL expression is increased in a fraction of human AML samples expressing RUNX1-ETO, a fusion protein created by chromosome translocation t(8;21), and that up-regulation of Mpl expression in mice induces AML when coexpressed with RUNX1-ETO. The leukemic cells are sensitive to THPO, activating survival and proliferative responses. Mpl expression is not regulated by RUNX1-ETO in mouse hematopoietic progenitors or leukemic cells. Moreover, we find that activation of PI3K/AKT but not ERK/MEK pathway is a critical mediator of the MPL-directed antiapoptotic function in leukemic cells. Hence, this study provides evidence that up-regulation of wild-type MPL levels promotes leukemia development and maintenance through activation of the PI3K/AKT axis, and suggests that inhibitors of this axis could be effective for treatment of MPL-positive AML. PMID:22613795

Thrombopoietin/MPL participates in initiating and maintaining RUNX1-ETO acute myeloid leukemia via PI3K/AKT signaling.

PubMed

Pulikkan, John Anto; Madera, Dmitri; Xue, Liting; Bradley, Paul; Landrette, Sean Francis; Kuo, Ya-Huei; Abbas, Saman; Zhu, Lihua Julie; Valk, Peter; Castilla, Lucio Hernán

2012-07-26

Oncogenic mutations in components of cytokine signaling pathways elicit ligand-independent activation of downstream signaling, enhancing proliferation and survival in acute myeloid leukemia (AML). The myeloproliferative leukemia virus oncogene, MPL, a homodimeric receptor activated by thrombopoietin (THPO), is mutated in myeloproliferative disorders but rarely in AML. Here we show that wild-type MPL expression is increased in a fraction of human AML samples expressing RUNX1-ETO, a fusion protein created by chromosome translocation t(8;21), and that up-regulation of Mpl expression in mice induces AML when coexpressed with RUNX1-ETO. The leukemic cells are sensitive to THPO, activating survival and proliferative responses. Mpl expression is not regulated by RUNX1-ETO in mouse hematopoietic progenitors or leukemic cells. Moreover, we find that activation of PI3K/AKT but not ERK/MEK pathway is a critical mediator of the MPL-directed antiapoptotic function in leukemic cells. Hence, this study provides evidence that up-regulation of wild-type MPL levels promotes leukemia development and maintenance through activation of the PI3K/AKT axis, and suggests that inhibitors of this axis could be effective for treatment of MPL-positive AML.

Biological and dosimetric characterisation of spatially fractionated proton minibeams

NASA Astrophysics Data System (ADS)

Meyer, Juergen; Stewart, Robert D.; Smith, Daniel; Eagle, James; Lee, Eunsin; Cao, Ning; Ford, Eric; Hashemian, Reza; Schuemann, Jan; Saini, Jatinder; Marsh, Steve; Emery, Robert; Dorman, Eric; Schwartz, Jeff; Sandison, George

2017-12-01

The biological effectiveness of proton beams varies with depth, spot size and lateral distance from the beam central axis. The aim of this work is to incorporate proton relative biological effectiveness (RBE) and equivalent uniform dose (EUD) considerations into comparisons of broad beam and highly modulated proton minibeams. A Monte Carlo model of a small animal proton beamline is presented. Dose and variable RBE is calculated on a per-voxel basis for a range of energies (30-109 MeV). For an open beam, the RBE values at the beam entrance ranged from 1.02-1.04, at the Bragg peak (BP) from 1.3 to 1.6, and at the distal end of the BP from 1.4 to 2.0. For a 50 MeV proton beam, a minibeam collimator designed to produce uniform dose at the depth of the BP peak, had minimal impact on the open beam RBE values at depth. RBE changes were observed near the surface when the collimator was placed flush with the irradiated object, due to a higher neutron contribution derived from proton interactions with the collimator. For proton minibeams, the relative mean RBE weighted entrance dose (RWD) was ~25% lower than the physical mean dose. A strong dependency of the EUD with fraction size was observed. For 20 Gy fractions, the EUD varied widely depending on the radiosensitivity of the cells. For radiosensitive cells, the difference was up to ~50% in mean dose and ~40% in mean RWD and the EUD trended towards the valley dose rather than the mean dose. For comparative studies of uniform dose with spatially fractionated proton minibeams, EUD derived from a per-voxel RWD distribution is recommended for biological assessments of reproductive cell survival and related endpoints.

Biological and dosimetric characterisation of spatially fractionated proton minibeams.

PubMed

Meyer, Juergen; Stewart, Robert D; Smith, Daniel; Eagle, James; Lee, Eunsin; Cao, Ning; Ford, Eric; Hashemian, Reza; Schuemann, Jan; Saini, Jatinder; Marsh, Steve; Emery, Robert; Dorman, Eric; Schwartz, Jeff; Sandison, George

2017-11-21

The biological effectiveness of proton beams varies with depth, spot size and lateral distance from the beam central axis. The aim of this work is to incorporate proton relative biological effectiveness (RBE) and equivalent uniform dose (EUD) considerations into comparisons of broad beam and highly modulated proton minibeams. A Monte Carlo model of a small animal proton beamline is presented. Dose and variable RBE is calculated on a per-voxel basis for a range of energies (30-109 MeV). For an open beam, the RBE values at the beam entrance ranged from 1.02-1.04, at the Bragg peak (BP) from 1.3 to 1.6, and at the distal end of the BP from 1.4 to 2.0. For a 50 MeV proton beam, a minibeam collimator designed to produce uniform dose at the depth of the BP peak, had minimal impact on the open beam RBE values at depth. RBE changes were observed near the surface when the collimator was placed flush with the irradiated object, due to a higher neutron contribution derived from proton interactions with the collimator. For proton minibeams, the relative mean RBE weighted entrance dose (RWD) was ~25% lower than the physical mean dose. A strong dependency of the EUD with fraction size was observed. For 20 Gy fractions, the EUD varied widely depending on the radiosensitivity of the cells. For radiosensitive cells, the difference was up to ~50% in mean dose and ~40% in mean RWD and the EUD trended towards the valley dose rather than the mean dose. For comparative studies of uniform dose with spatially fractionated proton minibeams, EUD derived from a per-voxel RWD distribution is recommended for biological assessments of reproductive cell survival and related endpoints.

Cytotoxic Components Against Human Oral Squamous Cell Carcinoma Isolated from Andrographis paniculata.

PubMed

Suzuki, Ryuichiro; Matsushima, Yasuaki; Okudaira, Noriyuki; Sakagami, Hiroshi; Shirataki, Yoshiaki

2016-11-01

The 5-year survival rate of patients with oral cancer has remained approximately 50% during the past 30 years, possibly due to the poor tumor selectivity of conventional anticancer drugs. This prompted us to search for new candidates for anticancer drugs that have higher cytotoxicity and tumor selectivity. Dried leaves of Andrographis paniculata were supplied from a market in Shanghai. The methanolic fraction of A. paniculata was further fractionated to identify cytotoxic principles by spectroscopic analysis and comparison with literature values. Viable cell number was determined by the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide method, and tumor specificity was calculated by relative cytotoxicity against oral squamous cell carcinoma cell lines compared to that against normal oral cells. Apoptosis induction was detected by cleaved poly (ADP-ribose) polymerase and caspase-3 on western blot analysis. Major cytotoxicity in the methanol extract of a leaf of A. paniculata was recovered by partitioning with EtOAc, followed by silica gel chromatography. Further purification with reversed-phase high-performance liquid chromatography led to isolation of four known cytotoxic compounds, 14-deoxyandrographolide, andrographolide, neoandrographolide and deoxyandrographiside. Among them, andrographolide had the greatest cytotoxicity and tumor specificity, also inducing caspase-3 activation of HSC-2 oral squamous cell carcinoma cells. The present study identified andrographolide as a major antitumor principle in the methanolic extract of leaves of A. paniculata. Copyright© 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

Embryonic stem cell grafting in normal and infarcted myocardium: serial assessment with MR imaging and PET dual detection.

PubMed

Qiao, Hui; Zhang, Hualei; Zheng, Yuanjie; Ponde, Datta E; Shen, Dinggang; Gao, Fabao; Bakken, Ashley B; Schmitz, Alexander; Kung, Hank F; Ferrari, Victor A; Zhou, Rong

2009-03-01

To use magnetic resonance (MR) imaging and positron emission tomography (PET) dual detection of cardiac-grafted embryonic stem cells (ESCs) to examine (a) survival and proliferation of ESCs in normal and infarcted myocardium, (b) host macrophage versus grafted ESC contribution to serial MR imaging signal over time, and (c) cardiac function associated with the formation of grafts and whether improvement in cardiac function is related to cardiac differentiation of ESCs. All animal procedures were approved by the institutional animal care and use committee. Murine ESCs were stably transfected with a mutant version of herpes simplex virus type 1 thymidine kinase, HSV1-sr39tk, and also were labeled with superparamagnetic iron oxide (SPIO) particles. Cells were injected directly in the border zone of the infarcted heart or in corresponding regions of normal hearts in athymic rats. PET and MR imaging were performed longitudinally for 4 weeks in the same animals. ESCs survived and underwent proliferation in the infarcted and normal hearts, as demonstrated by serial increases in 9-(4-[(18)F]fluoro-3-hydroxymethylbutyl) guanine PET signals. In parallel, the hypointense areas on MR images at the injection sites decreased over time. Double staining for host macrophages and SPIO particles revealed that the majority of SPIO-containing cells were macrophages at week 4 after injection. Left ventricular ejection fraction increased in the ESC-treated rats but decreased in culture media-treated rats, and border-zone function was preserved in ESC-treated animals; however, cardiac differentiation of ESCs was less than 0.5%. Dual-modality imaging permits complementary information in regard to cell survival and proliferation, graft formation, and effects on cardiac function. http://radiology.rsnajnls.org/cgi/content/full/250/3/821/DC1. RSNA, 2009

Anti-apoptotic A1 is not essential for lymphoma development in Eµ-Myc mice but helps sustain transplanted Eµ-Myc tumour cells.

PubMed

Mensink, Mark; Anstee, Natasha S; Robati, Mikara; Schenk, Robyn L; Herold, Marco J; Cory, Suzanne; Vandenberg, Cassandra J

2018-03-01

The transcription factor c-MYC regulates a multiplicity of genes involved in cellular growth, proliferation, metabolism and DNA damage response and its overexpression is a hallmark of many tumours. Since MYC promotes apoptosis under conditions of stress, such as limited availability of nutrients or cytokines, MYC-driven cells are very much dependent on signals that inhibit cell death. Stress signals trigger apoptosis via the pathway regulated by opposing fractions of the BCL-2 protein family and previous genetic studies have shown that the development of B lymphoid tumours in Eµ-Myc mice is critically dependent on expression of pro-survival BCL-2 relatives MCL-1, BCL-W and, to a lesser extent, BCL-X L , but not BCL-2 itself, and that sustained growth of these lymphomas is dependent on MCL-1. Using recently developed mice that lack expression of all three functional pro-survival A1 genes, we show here that the kinetics of lymphoma development in Eµ-Myc mice and the competitive repopulation capacity of Eµ-Myc haemopoietic stem and progenitor cells is unaffected by the absence of A1. However, conditional loss of a single remaining functional A1 gene from transplanted A1-a -/- A1-b fl/fl A1-c -/- Eµ-Myc lymphomas slowed their expansion, significantly extending the life of the transplant recipients. Thus, A1 contributes to the survival of malignant Eµ-Myc-driven B lymphoid cells. These results strengthen the case for BFL-1, the human homologue of A1, being a valid target for drug development for MYC-driven tumours.

Clinical results of definitive-dose (50 Gy/25 fractions) preoperative chemoradiotherapy for unresectable esophageal cancer.

PubMed

Ishikawa, Kazuki; Nakamatsu, Kiyoshi; Shiraishi, Osamu; Yasuda, Takushi; Nishimura, Yasumasa

2015-06-01

The clinical results of definitive-dose preoperative chemoradiotherapy (CRT) of 50 Gy/25 fractions/5 weeks for unresectable esophageal cancer were analyzed. Inclusion criteria were unresectable esophageal squamous cell carcinoma with T4b or mediastinal lymph nodes invading to the trachea or aorta. Radiation therapy of 50 Gy/25 fractions/5 weeks was combined concurrently with two courses of FP therapy (CDDP 70 mg/m(2) + 5-FU 700 mg/m(2)/d × 5 days: day 1-5, day 29-33). Tumor response was evaluated 4 weeks after completion of RT. Subtotal esophagectomy was planned 6-8 weeks after RT. Thirty patients (26 male and 4 female) aged from 50-78 years (median 66) were enrolled between 2008 and 2011. The clinical stages according to the 7th edition of UICC were stages II/III/IV, 1/23/6; T1/2/3/4, 1/1/4/24; and N0/1/2/3, 3/25/1/1. All 30 patients completed RT of 50 Gy/25 fractions. Initial tumor responses were 21 patients with resectable disease, 7 with unresectable disease, and 2 with progressive disease. Subtotal esophagectomy was performed in 18 (60%) of the 30 patients. Pathological complete response was obtained in five (28%) patients. There were two patients with hospitalization death after surgery (11%). Six of the 7 patients who still had unresectable disease were treated with 1-3 courses of docetaxel, CDDP and 5-FU. Three patients treated without surgery showed long-term survival. The 3-year loco-regional control rate and the 3-year overall survival rate for the 30 patients were 70 and 49%, respectively. Definitive-dose preoperative CRT was feasible, and is a promising treatment strategy for unresectable esophageal cancer.

Patterns of Care Among Patients Receiving Radiation Therapy for Bone Metastases at a Large Academic Institution

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ellsworth, Susannah G.; Alcorn, Sara R., E-mail: salcorn2@jhmi.edu; Hales, Russell K.

Purpose: This study evaluates outcomes and patterns of care among patients receiving radiation therapy (RT) for bone metastases at a high-volume academic institution. Methods and Materials: Records of all patients whose final RT course was for bone metastases from April 2007 to July 2012 were identified from electronic medical records. Chart review yielded demographic and clinical data. Rates of complicated versus uncomplicated bone metastases were not analyzed. Results: We identified 339 patients whose final RT course was for bone metastases. Of these, 52.2% were male; median age was 65 years old. The most common primary was non-small-cell lung cancer (29%). Most patientsmore » (83%) were prescribed ≤10 fractions; 8% received single-fraction RT. Most patients (52%) had a documented goals of care (GOC) discussion with their radiation oncologist; hospice referral rates were higher when patients had such discussions (66% with vs 50% without GOC discussion, P=.004). Median life expectancy after RT was 96 days. Median survival after RT was shorter based on inpatient as opposed to outpatient status at the time of consultation (35 vs 136 days, respectively, P<.001). Hospice referrals occurred for 56% of patients, with a median interval between completion of RT and hospice referral of 29 days and a median hospice stay of 22 days. Conclusions: These data document excellent adherence to American Society for Radiation Oncolology Choosing Wisely recommendation to avoid routinely using >10 fractions of palliative RT for bone metastasis. Nonetheless, single-fraction RT remains relatively uncommon. Participating in GOC discussions with a radiation oncologist is associated with higher rates of hospice referral. Inpatient status at consultation is associated with short survival.« less

Phase 2 Study of Docetaxel, Cisplatin, and Concurrent Radiation for Technically Resectable Stage III-IV Squamous Cell Carcinoma of the Head and Neck

DOE Office of Scientific and Technical Information (OSTI.GOV)

Inohara, Hidenori, E-mail: hinohara@ent.med.osaka-u.ac.jp; Takenaka, Yukinori; Yoshii, Tadashi

2015-04-01

Purpose: We investigated the efficacy and safety of weekly low-dose docetaxel and cisplatin therapy concurrent with conventionally fractionated radiation in patients with technically resectable stage III-IV squamous cell carcinoma of the head and neck. Methods and Materials: Between March 2004 and October 2011, we enrolled 117 patients, of whom 116 were analyzable (43 had oropharyngeal cancer, 54 had hypopharyngeal cancer, and 19 had laryngeal cancer), and 85 (73%) had stage IV disease. Radiation consisted of 66 Gy in 33 fractions. Docetaxel, 10 mg/m{sup 2}, followed by cisplatin, 20 mg/m{sup 2}, administered on the same day were given once a week for 6 cycles.more » The primary endpoint was overall complete response (CR) rate after chemoradiation therapy. Human papillomavirus (HPV) DNA in oropharyngeal cancer was examined by PCR. Results: Of 116 patients, 82 (71%) completed treatment per protocol; 102 (88%) received the full radiation therapy dose; and 90 (78%) and 12 (10%) patients received 6 and 5 chemotherapy cycles, respectively. Overall CR rate was 71%. After median follow-up of 50.9 months (range: 15.6-113.9 months for surviving patients), 2-year and 4-year overall survival rates were 82% and 68%, respectively. Cumulative 2-year and 4-year local failure rates were 27% and 28%, respectively, whereas distant metastasis rates were 15% and 22%, respectively. HPV status in oropharyngeal cancer was not associated with treatment efficacy. Acute toxicity included grade 3 and 4 in-field mucositis in 73% and 5% of patients, respectively, whereas myelosuppression and renal injury were minimal. No patients died of toxicity. Feeding tube dependence in 8% and tracheostomy in 1% of patients were evident at 2 years postchemoradiation therapy in patients who survived without local treatment failure. Conclusions: Local control and survival with this regimen were satisfactory. Although acute toxicity, such as mucositis, was common, late toxicity, such as laryngoesophageal dysfunction, was minimal. Therapy using weekly low-dose docetaxel and cisplatin concurrent with radiation warrants further evaluation.« less

Validation of 64Cu-ATSM damaging DNA via high-LET Auger electron emission.

PubMed

McMillan, Dayton D; Maeda, Junko; Bell, Justin J; Genet, Matthew D; Phoonswadi, Garrett; Mann, Kelly A; Kraft, Susan L; Kitamura, Hisashi; Fujimori, Akira; Yoshii, Yukie; Furukawa, Takako; Fujibayashi, Yasuhisa; Kato, Takamitsu A

2015-09-01

Radioactive copper (II) (diacetyl-bis N4-methylthiosemicarbazone) (Cu-ATSM) isotopes were originally developed for the imaging of hypoxia in tumors. Because the decay of a (64)Cu atom is emitting not only positrons but also Auger electrons, this radionuclide has great potential as a theranostic agent. However, the success of (64)Cu-ATSM internal radiation therapy would depend on the contribution of Auger electrons to tumor cell killing. Therefore, we designed a cell culture system to define the contributions to cell death from Auger electrons to support or refute our hypothesis that the majority of cell death from (64)Cu-ATSM is a result of high-LET Auger electrons and not positrons or other low-LET radiation. Chinese hamster ovary (CHO) wild type and DNA repair-deficient xrs5 cells were exposed to (64)Cu-ATSM during hypoxic conditions. Surviving fractions were compared with those surviving gamma-radiation, low-LET hadron radiation, and high-LET heavy ion exposure. The ratio of the D(10) values (doses required to achieve 10% cell survival) between CHO wild type and xrs5 cells suggested that (64)Cu-ATSM toxicity is similar to that of high-LET Carbon ion radiation (70 keV/μm). γH2AX foci assays confirmed DNA double-strand breaks and cluster damage by high-LET Auger electrons from (64)Cu decay, and complex types of chromosomal aberrations typical of high-LET radiation were observed after (64)Cu-ATSM exposure. The majority of cell death was caused by high-LET radiation. This work provides strong evidence that (64)Cu-ATSM damages DNA via high-LET Auger electrons, supporting further study and consideration of (64)Cu-ATSM as a cancer treatment modality for hypoxic tumors. © The Author 2015. Published by Oxford University Press on behalf of The Japan Radiation Research Society and Japanese Society for Radiation Oncology.

Icotinib and whole-brain radiotherapy for the treatment in patients with brain metastases from EGFR-mutant nonsmall cell lung cancer

PubMed Central

Jiang, Ai-Ying; Zhang, Jing; Luo, Hai-Long; Gao, Feng; Lv, Yu-Feng

2018-01-01

Abstract This study aimed to explore the effect and toxicity of icotinib and whole-brain radiotherapy (IWBRT) for the treatment of brain metastases from nonsmall cell lung cancer (BMNSCLC) with epidermal growth factor receptor (EGFR)-mutant among Chinese Han population. A total of 55 patients with EGFR-mutant BMNSCLC were included. They received orally icotinib (125 mg/tablet, 125 mg each time, 3 times daily) until disease progression. In addition, they also underwent whole-brain radiotherapy (3-Gy fractions once daily, 5 days weekly for a total dose of 30 Gy) in an attempt to extend their survival time. The outcomes consisted of complete response (CR), partial response (PR), stable disease (SD), progress disease (PD), overall response rate (ORR), progression-free survival (PFS), and overall survival (OS). In addition, toxicity was also recorded in this study. The CR, PR, SD, PD, ORR, PFS, and OS were 38.2%, 52.8%, 5.4%, 3.6%, 90.1%, 12.5%, and 48.0% months, respectively. In addition, mild toxicity was observed in this study. This study demonstrated that IWBRT is efficacious with acceptable toxicity for patients with EGFR-mutant BMNSCLC among Chinese Han population. PMID:29642161

Icotinib and whole-brain radiotherapy for the treatment in patients with brain metastases from EGFR-mutant nonsmall cell lung cancer: A retrospective study.

PubMed

Jiang, Ai-Ying; Zhang, Jing; Luo, Hai-Long; Gao, Feng; Lv, Yu-Feng

2018-04-01

This study aimed to explore the effect and toxicity of icotinib and whole-brain radiotherapy (IWBRT) for the treatment of brain metastases from nonsmall cell lung cancer (BMNSCLC) with epidermal growth factor receptor (EGFR)-mutant among Chinese Han population.A total of 55 patients with EGFR-mutant BMNSCLC were included. They received orally icotinib (125 mg/tablet, 125 mg each time, 3 times daily) until disease progression. In addition, they also underwent whole-brain radiotherapy (3-Gy fractions once daily, 5 days weekly for a total dose of 30 Gy) in an attempt to extend their survival time. The outcomes consisted of complete response (CR), partial response (PR), stable disease (SD), progress disease (PD), overall response rate (ORR), progression-free survival (PFS), and overall survival (OS). In addition, toxicity was also recorded in this study.The CR, PR, SD, PD, ORR, PFS, and OS were 38.2%, 52.8%, 5.4%, 3.6%, 90.1%, 12.5%, and 48.0% months, respectively. In addition, mild toxicity was observed in this study.This study demonstrated that IWBRT is efficacious with acceptable toxicity for patients with EGFR-mutant BMNSCLC among Chinese Han population.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cho, Kwan Ho; Ahn, Sung Ja; Pyo, Hong Ryull

Purpose: We evaluated the efficacy of synchronous three-dimensional (3D) conformal boost to the gross tumor volume (GTV) in concurrent chemoradiotherapy for patients with locally advanced non-small-cell lung cancer (NSCLC). Methods and Materials: Eligibility included unresectable Stage III NSCLC with no pleural effusion, no supraclavicular nodal metastases, and Eastern Cooperative Oncology Group performance score of 0-1. Forty-nine patients with pathologically proven NSCLC were enrolled. Eighteen patients had Stage IIIA and 31 had Stage IIIB. By using 3D conformal radiotherapy (RT) techniques, a dose of 1.8 Gy was delivered to the planning target volume with a synchronous boost of 0.6 Gy tomore » the GTV, with a total dose of 60 Gy to the GTV and 45 Gy to the planning target volume in 25 fractions during 5 weeks. All patients received weekly chemotherapy consisting of paclitaxel and carboplatin during RT. Results: With a median follow-up of 36.8 months (range, 29.0-45.5 months) for surviving patients, median survival was 28.1 months. One-, 2- and 3-year overall survival rates were 77%, 56.4%, and 43.8%, respectively. Corresponding local progression-free survival rates were 71.2%, 53.7%, and 53.7%. Compliance was 90% for RT and 88% for chemotherapy. Acute esophagitis of Grade 2 or higher occurred in 29 patients. Two patients with T4 lesions died of massive bleeding and hemoptysis during treatment (Grade 5). Overall late toxicity was acceptable. Conclusions: Based on the favorable outcome with acceptable toxicity, the acceleration scheme using 3D conformal GTV boost in this trial is warranted to compare with conventional fractionation in a Phase III trial.« less

Accelerated hyperfractionated radiotherapy for cervical cancer: multi-institutional prospective study of forum for nuclear cooperation in Asia among eight Asian countries.

PubMed

Ohno, Tatsuya; Nakano, Takashi; Kato, Shingo; Koo, Cho Chul; Chansilpa, Yaowalak; Pattaranutaporn, Pittayapoom; Calaguas, Miriam Joy C; de Los Reyes, Rey H; Zhou, Beibei; Zhou, Juying; Susworo, Raden; Supriana, Nana; Dung, To Anh; Ismail, Fuad; Sato, Sinichiro; Suto, Hisao; Kutsutani-Nakamura, Yuzuru; Tsujii, Hirohiko

2008-04-01

To evaluate the toxicity and efficacy of accelerated hyperfractionated radiotherapy (RT) for locally advanced cervical cancer. A multi-institutional prospective single-arm study was conducted among eight Asian countries. Between 1999 and 2002, 120 patients (64 with Stage IIB and 56 with Stage IIIB) with squamous cell carcinoma of the cervix were treated with accelerated hyperfractionated RT. External beam RT consisted of 30 Gy to the whole pelvis, 1.5 Gy/fraction twice daily, followed by 20 Gy of pelvic RT with central shielding at a dose of 2-Gy fractions daily. A small bowel displacement device was used with the patient in the prone position. In addition to central shielding RT, intracavitary brachytherapy was started. Acute and late morbidities were graded according to the Radiation Therapy Oncology Group and Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer criteria. The median overall treatment time was 35 days. The median follow-up time for surviving patients was 4.7 years. The 5-year pelvic control and overall survival rate for all patients was 84% and 70%, respectively. The 5-year pelvic control and overall survival rate was 78% and 69% for tumors > or = 6 cm in diameter, respectively. No treatment-related death occurred. Grade 3-4 late toxicities of the small intestine, large intestine, and bladder were observed in 1, 1, and 2 patients, respectively. The 5-year actuarial rate of Grade 3-4 late toxicity at any site was 5%. The results of our study have shown that accelerated hyperfractionated RT achieved sufficient pelvic control and survival without increasing severe toxicity. This treatment could be feasible in those Asian countries where chemoradiotherapy is not available.

Rosiglitazone reduces body wasting and improves survival in a rat model of cancer cachexia.

PubMed

Trobec, Katja; Palus, Sandra; Tschirner, Anika; von Haehling, Stephan; Doehner, Wolfram; Lainscak, Mitja; Anker, Stefan D; Springer, Jochen

2014-09-01

Rosiglitazone improves insulin sensitivity and promotes weight gain in patients with type 2 diabetes mellitus, which could be useful in wasting and cachexia. However, its effects on cardiac function are controversial. The aim of this study was to investigate the effects of rosiglitazone on body wasting, body composition, cardiac function, and survival in a rat model of cancer cachexia. Rats were injected with Yoshida AH-130 hepatoma tumor cells and randomized to receive placebo or rosiglitazone 4 mg/kg daily. Treatment started 1 d after tumor inoculation and the rats were sacrificed 14 d thereafter. Body weight and body composition was measured at baseline and after removal of tumor. Echocardiography was performed at baseline and on day 11. At the end of the study, organs were weighed and the proteasome activity in gastrocnemius muscle was measured. Survival analysis showed a significant benefit from treatment with rosiglitazone (hazard ratio = 0.38, 95% confidence interval: 0.15-0.86). Rosiglitazone reduced average daily weight loss (2.33 g/d rosiglitazone versus 3.93 g/d placebo; P < 0.05) as a result of both fat and lean mass preservation. It decelerated white and brown tissue wasting, but had no effect on skeletal muscle mass and heart mass. However, peptidyl-glutamyl-protein-hydrolysing and trypsin-like activity in gastrocnemius muscle was significantly reduced by rosiglitazone. Finally, it increased left ventricular ejection fraction, fractional shortening, and systolic volume and improved cardiac output in cachectic cancer rats. Rosiglitazone prevents weight loss and improves survival in a rat model of cancer cachexia. It exerts beneficial effects on cardiac function. Copyright © 2014 Elsevier Inc. All rights reserved.

Accelerated Hyperfractionated Radiotherapy for Cervical Cancer: Multi-Institutional Prospective Study of Forum for Nuclear Cooperation in Asia Among Eight Asian Countries

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ohno, Tatsuya; Nakano, Takashi; Kato, Shingo

2008-04-01

Purpose: To evaluate the toxicity and efficacy of accelerated hyperfractionated radiotherapy (RT) for locally advanced cervical cancer. Methods and Materials: A multi-institutional prospective single-arm study was conducted among eight Asian countries. Between 1999 and 2002, 120 patients (64 with Stage IIB and 56 with Stage IIIB) with squamous cell carcinoma of the cervix were treated with accelerated hyperfractionated RT. External beam RT consisted of 30 Gy to the whole pelvis, 1.5 Gy/fraction twice daily, followed by 20 Gy of pelvic RT with central shielding at a dose of 2-Gy fractions daily. A small bowel displacement device was used with themore » patient in the prone position. In addition to central shielding RT, intracavitary brachytherapy was started. Acute and late morbidities were graded according to the Radiation Therapy Oncology Group and Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer criteria. Results: The median overall treatment time was 35 days. The median follow-up time for surviving patients was 4.7 years. The 5-year pelvic control and overall survival rate for all patients was 84% and 70%, respectively. The 5-year pelvic control and overall survival rate was 78% and 69% for tumors {>=}6 cm in diameter, respectively. No treatment-related death occurred. Grade 3-4 late toxicities of the small intestine, large intestine, and bladder were observed in 1, 1, and 2 patients, respectively. The 5-year actuarial rate of Grade 3-4 late toxicity at any site was 5%. Conclusion: The results of our study have shown that accelerated hyperfractionated RT achieved sufficient pelvic control and survival without increasing severe toxicity. This treatment could be feasible in those Asian countries where chemoradiotherapy is not available.« less

Nationwide, Multicenter, Retrospective Study on High-Dose-Rate Brachytherapy as Monotherapy for Prostate Cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yoshioka, Yasuo, E-mail: yoshioka@radonc.med.osaka-u.ac.jp; Kotsuma, Tadayuki; Komiya, Akira

Purpose: To present, analyze, and discuss results of a nationwide, multicenter, retrospective study on high-dose-rate brachytherapy (HDR-BT) as monotherapy for low-, intermediate-, and high-risk prostate cancer. Methods and Materials: From 1995 through 2013, 524 patients, 73 (14%) with low-risk, 207 (40%) with intermediate-risk, and 244 (47%) with high-risk prostate cancer, were treated with HDR-BT as monotherapy at 5 institutions in Japan. Dose fractionations were 27 Gy/2 fractions for 69 patients (13%), 45.5 Gy/7 fractions for 168 (32%), 49 Gy/7 fractions for 149 (28%), 54 Gy/9 fractions for 130 (25%), and others for 8 (2%). Of these patients, 156 (30%) did not receive androgen deprivationmore » therapy, and 202 patients (39%) did receive androgen deprivation therapy <1 year, 112 (21%) for 1-3 years, and 54 (10%) for >3 years. Median follow-up time was 5.9 years (range, 0.4-18.1 years), with a minimum of 2 years for surviving patients. Results: After 5 years, respective actuarial rates of no biochemical evidence of disease, overall survival, cause-specific survival, and metastasis-free survival for all patients were 92%, 97%, 99%, and 94%. For low/intermediate/high-risk patients, the 5-year no biochemical evidence of disease rates were 95%/94%/89%, the 5-year overall survival rates were 98%/98%/94%, the 5-year cause-specific survival rates were 98%/100%/98%, and the 5-year metastasis-free survival rates were 98%/95%/90%, respectively. The cumulative incidence of late grade 2 to 3 genitourinary toxicity at 5 years was 19%, and that of late grade 3 was 1%. The corresponding incidences of gastrointestinal toxicity were 3% and 0% (0.2%). No grade 4 or 5 of either type of toxicity was detected. Conclusions: The findings of this nationwide, multicenter, retrospective study demonstrate that HDR-BT as monotherapy was safe and effective for all patients with low-, intermediate-, and high-risk prostate cancer.« less

Brazilian red propolis: phytochemical screening, antioxidant activity and effect against cancer cells.

PubMed

de Mendonça, Izabel Cristina Gomes; Porto, Isabel Cristina Celerino de Moraes; do Nascimento, Ticiano Gomes; de Souza, Naiana Soares; Oliveira, José Marcos dos Santos; Arruda, Rodolfo Elleson dos Santos; Mousinho, Kristiana Cerqueira; dos Santos, Aldenir Feitosa; Basílio-Júnior, Irinaldo Diniz; Parolia, Abhishek; Barreto, Francisco Stefânio

2015-10-14

The implementation of new public healthcare models that stimulate the use of natural products from traditional medicine, as a so-called integrated medicine, refers to an approach that use best of both conventional medicine and traditional medicine. Propolis is a widely used natural product by different ancient cultures and known to exhibit biological activities beneficial for health. The large number of studies conducted with propolis had shown that its chemical composition differs as a function of the climate, plant diversity and bee species and plays an important role on its therapeutic properties. The aim of this study was to analyse the phytochemical profile of the ethanolic extract of red propolis (EEP) and its fractionation, antioxidant action of EEP and its fractions hexane, cloroform and ethyl acetate and cytotoxic activity of EEP on human tumour cell lines SF-295 (glioblastoma), OVCAR-8 (ovary) and HCT-116 (colon). EEP was obtained by maceration with absolute ethanol, then it was concentrated in rotaevaporator up to complete evaporation of the solvent. The crude extract was fractionated with hexane, ethyl acetate, chloroform and methanol and they were subjected to phytochemical screening and total phenolic compounds. Antioxidant activity of EEP and fractions was done by means of the 2,2-diphenyl-1-picryhydrazyl (DPPH) method. Biomarkers of red propolis were identified by LC-Orbitrap-FTMS. To assess cytotoxic activity of the extract, cells were exposed to EEP over 72 h. Cell viability was assessed by means of MTT assay. The percentage of cell growth inhibition (IC50) was analysed by means of non-linear regression, and the absorbance values of the various investigated concentrations were subjected to one-factor analysis of variance (ANOVA) followed by Tukey's or Tamhane's tests (α = 0.05). The results obtained using phytochemical screening and LC-Orbitrap-FTMS indicated the presence of phlobaphene tannins, catechins, chalcones, aurones, flavonones, flavonols, xanthones, pentacyclic triterpenoids and guttiferones in Brazilian red propolis. EEP and its hexane, chloroform and ethyl acetate fractions obtained by liquid-liquid partitioning exhibited satisfactory antioxidant percentages. EEP (IC50 < 34.27 μg/mL) exhibited high levels of cytotoxicity on all human tumour cell lines tested when compared to negative control. C-Orbitrap-FTMS was useful to establish the chemical profile of the red propolis. Brazilian red propolis has antioxidant properties and decreases substantially the percentage of cell survival of human tumour cells; thus, it has potential to serve as an anticancer drug.

TET2 mutations predict response to hypomethylating agents in myelodysplastic syndrome patients

PubMed Central

Lord, Allegra; Stevenson, Kristen; Bar-Natan, Michal; Pérez-Ladaga, Albert; Zaneveld, Jacques; Wang, Hui; Caughey, Bennett; Stojanov, Petar; Getz, Gad; Garcia-Manero, Guillermo; Kantarjian, Hagop; Chen, Rui; Stone, Richard M.; Neuberg, Donna; Steensma, David P.; Ebert, Benjamin L.

2014-01-01

Only a minority of myelodysplastic syndrome (MDS) patients respond to hypomethylating agents (HMAs), but strong predictors of response are unknown. We sequenced 40 recurrently mutated myeloid malignancy genes in tumor DNA from 213 MDS patients collected before treatment with azacitidine (AZA) or decitabine (DEC). Mutations were examined for association with response and overall survival. The overall response rate of 47% was not different between agents. Clonal TET2 mutations predicted response (odds ratio [OR] 1.99, P = .036) when subclones unlikely to be detected by Sanger sequencing (allele fraction <10%) were treated as wild-type (WT). Response rates were highest in the subset of TET2 mutant patients without clonal ASXL1 mutations (OR 3.65, P = .009). Mutations of TP53 (hazard ratio [HR] 2.01, P = .002) and PTPN11 (HR 3.26, P = .006) were associated with shorter overall survival but not drug response. Murine-competitive bone marrow transplantation followed by treatment with AZA demonstrated that Tet2-null cells have an engraftment advantage over Tet2-WT cells. AZA significantly decreased this advantage for Tet2-null cells (P = .002) but not Tet2-WT cells (P = .212). Overall, Tet2 loss appears to sensitize cells to treatment with AZA in vivo, and TET2 mutations can identify patients more likely to respond to HMAs. PMID:25224413

TET2 mutations predict response to hypomethylating agents in myelodysplastic syndrome patients.

PubMed

Bejar, Rafael; Lord, Allegra; Stevenson, Kristen; Bar-Natan, Michal; Pérez-Ladaga, Albert; Zaneveld, Jacques; Wang, Hui; Caughey, Bennett; Stojanov, Petar; Getz, Gad; Garcia-Manero, Guillermo; Kantarjian, Hagop; Chen, Rui; Stone, Richard M; Neuberg, Donna; Steensma, David P; Ebert, Benjamin L

2014-10-23

Only a minority of myelodysplastic syndrome (MDS) patients respond to hypomethylating agents (HMAs), but strong predictors of response are unknown. We sequenced 40 recurrently mutated myeloid malignancy genes in tumor DNA from 213 MDS patients collected before treatment with azacitidine (AZA) or decitabine (DEC). Mutations were examined for association with response and overall survival. The overall response rate of 47% was not different between agents. Clonal TET2 mutations predicted response (odds ratio [OR] 1.99, P = .036) when subclones unlikely to be detected by Sanger sequencing (allele fraction <10%) were treated as wild-type (WT). Response rates were highest in the subset of TET2 mutant patients without clonal ASXL1 mutations (OR 3.65, P = .009). Mutations of TP53 (hazard ratio [HR] 2.01, P = .002) and PTPN11 (HR 3.26, P = .006) were associated with shorter overall survival but not drug response. Murine-competitive bone marrow transplantation followed by treatment with AZA demonstrated that Tet2-null cells have an engraftment advantage over Tet2-WT cells. AZA significantly decreased this advantage for Tet2-null cells (P = .002) but not Tet2-WT cells (P = .212). Overall, Tet2 loss appears to sensitize cells to treatment with AZA in vivo, and TET2 mutations can identify patients more likely to respond to HMAs. © 2014 by The American Society of Hematology.

Brain tumour stem cells: implications for cancer therapy and regenerative medicine.

PubMed

Sanchez-Martin, Manuel

2008-09-01

The cancer relapse and mortality rate suggest that current therapies do not eradicate all malignant cells. Currently, it is accepted that tumorigenesis and organogenesis are similar in many respects, as for example, homeostasis is governed by a distinct sub-population of stem cells in both situations. There is increasing evidence that many types of cancer contain their own stem cells: cancer stem cells (CSC), which are characterized by their self-renewing capacity and differentiation ability. The investigation of solid tumour stem cells has gained momentum particularly in the area of brain tumours. Gliomas are the most common type of primary brain tumours. Nearly two-thirds of gliomas are highly malignant lesions with fast progression and unfortunate prognosis. Despite recent advances, two-year survival for glioblastoma (GBM) with optimal therapy is less than 30%. Even among patients with low-grade gliomas that confer a relatively good prognosis, treatment is almost never curative. Recent studies have demonstrated the existence of a small fraction of glioma cells endowed with features of primitive neural progenitor cells and a tumour-initiating function. In general, this fraction is characterized for forming neurospheres, being endowed with drug resistance properties and often, we can isolate some of them using sorting methods with specific antibodies. The molecular characterization of these stem populations will be critical to developing an effective therapy for these tumours with very dismal prognosis. To achieve this aim, the development of a mouse model which recapitulates the nature of these tumours is essential. This review will focus on glioma stem cell knowledge and discuss future implications in brain cancer therapy and regenerative medicine.

Radiation-Free Weekend Rescued! Continuous Accelerated Irradiation of 7-Days per Week Is Equal to Accelerated Fractionation With Concomitant Boost of 7 Fractions in 5-Days per Week: Report on Phase 3 Clinical Trial in Head-and-Neck Cancer Patients

DOE Office of Scientific and Technical Information (OSTI.GOV)

Skladowski, Krzysztof, E-mail: skladowski@io.gliwice.pl; Hutnik, Marcin; Wygoda, Andrzej

2013-03-01

Purpose: To report long-term results of randomized trial comparing 2 accelerated fractionations of definitive radiation therapy assessing the need to irradiate during weekend in patients with head and neck squamous cell carcinoma. Methods and Materials: A total of 345 patients with SCC of the oral cavity, larynx, and oro- or hypo-pharynx, stage T2-4N0-1M0, were randomized to receive continuous accelerated irradiation (CAIR: once per day, 7 days per week) or concomitant accelerated boost (CB: once per day, 3 days per week, and twice per day, 2 days per week). Total dose ranged from 66.6-72 Gy, dose per fraction was 1.8 Gy,more » number of fractions ranged from 37-40 fractions, and overall treatment time ranged from 37-40 days. Results: No differences for all trial end-points were noted. At 5 and 10 years, the actuarial rates of local-regional control were 63% and 60% for CAIR vs 65% and 60% for CB, and the corresponding overall survival were 40% and 25% vs 44% and 25%, respectively. Confluent mucositis was the main acute toxicity, with an incidence of 89% in CAIR and 86% in CB patients. The 5-year rate of grade 3-4 late radiation morbidity was 6% for both regimens. Conclusions: Results of this trial indicate that the effects of accelerated fractionation can be achieve by delivering twice-per-day irradiation on weekday(s). This trial has also confirmed that an accelerated, 6-weeks schedule is a reasonable option for patients with intermediate-stage head-and-neck squamous cell carcinoma because of the associated high cure rate and minimal severe late toxicity.« less

Microscopic observation of intracellular ice formation in unfertilized mouse ova as a function of cooling rate

DOE Office of Scientific and Technical Information (OSTI.GOV)

Leibo, S.P.; McGrath, J.J.; Cravalho, E.G.

A physical-chemical analysis of water loss from cells at subzero temperatures has shown that the likelihood of intracellular ice formation increased with increasing cooling rate. We have now used a modified version of a unique conduction-cooled cryomicroscope stage to observe the freezing of unfertilized mouse ova suspended in dimethyl sulfoxide. Survival measurements showed that the respective survivals of ova were about 65, 56, and 0% when they were cooled at rates of 0.2 to 1.5, 2.5, and 5.4/sup 0/C/min. Direct microscopic observation of mouse ova during freezing showed that the respective fractions of cells that foze intracellularly were 13, 72,more » and 100% when they were cooled at rates of 1.3, 2.9, and 4.8/sup 0/C/min or faster. These values agree with those predicted from the physical-chemical analysis for cells the size of mouse ova. The microscopic observations have also shown that intracellular freezing generally occurred at about -40 to -45/sup 0/C. We had previously observed that mouse embryos must be cooled slowly to -50/sup 0/C or below if they are to survive subsequent rapid cooling to -196/sup 0/C. The observation of intracellular ice formation at -45/sup 0/C supports the interpretation that at temperatures above -50/sup 0/C the embryos still contain water capable of freezing intracellulary.« less

THE OPPORTUNISTIC PATHOGEN TOXOPLASMA GONDII DEPLOYS A DIVERSE LEGION OF INVASION AND SURVIVAL PROTEINS

PubMed Central

Zhou, Xing W.; Kafsack, Björn F. C.; Cole, Robert N.; Beckett, Phil; Shen, Rong F.; Carruthers, Vern B.

2006-01-01

Host cell invasion is an essential step during infection by Toxoplasma gondii, an intracellular protozoan that causes the severe opportunistic disease toxoplasmosis in humans. Recent evidence strongly suggests that proteins discharged from Toxoplasma apical secretory organelles (micronemes, dense granules, and rhoptries) play key roles in host cell invasion and survival during infection. However, to date, only a limited number of secretory proteins have been discovered and the full spectrum of effector molecules involved in parasite invasion and survival remains unknown. To address these issues, we analyzed a large cohort of freely released Toxoplasma secretory proteins using two complementary methodologies, 2-DE/MS and LC/ESI-MS-MS (MudPIT, shotgun proteomics). Visualization of Toxoplasma secretory products by 2-DE revealed ∼100 spots, most of which were successfully identified by protein microsequencing or MALDI-MS analysis. Many proteins were present in multiple species suggesting they are subjected to substantial posttranslational modification. Shotgun proteomic analysis of the secretory fraction revealed several additional products including novel putative adhesive proteins, proteases, and hypothetical secretory proteins similar to products expressed by other related parasites including Plasmodium, the etiologic agent of malaria. A subset of novel proteins were re-expressed as fusions to yellow fluorescent protein and this initial screen revealed shared and distinct localizations within secretory compartments of T. gondii tachyzoites. The findings provide a uniquely broad view of Toxoplasma secretory proteins that participate in parasite survival and pathogenesis during infection. PMID:16002397

Stereotactic ablative radiotherapy (SABR) using 70 Gy in 10 fractions for non-small cell lung cancer: exploration of clinical indications.

PubMed

Li, Qiaoqiao; Swanick, Cameron W; Allen, Pamela K; Gomez, Daniel R; Welsh, James W; Liao, Zhongxing; Balter, Peter A; Chang, Joe Y

2014-08-01

We report our outcomes for patients with NSCLC treated with SABR to 70 Gy in 10 fractions and propose indications for this regimen as well as new dose-volume constraints. Volumetric image-guided SABR was used to treat 82 patients with clinical challenging NSCLC, not suitable for 50 Gy in 4 fractions, to a final dose of 70 Gy in 10 fractions. Endpoints included overall survival (OS), toxicity, and disease control. At a median follow-up time of 21.1 months, 2-year OS and local control rates were 66.9% and 96.2%, respectively. The most common side effects were radiation pneumonitis (14.6% grade 2, 2.4% grade 3), followed by chest wall pain (4.9% grade 2, 1.2% grade 3). Multivariate analysis revealed chest wall V50>60 cm(3) to be associated with chest wall pain. No patient developed brachial plexopathy. One patient with bronchial tree tumor invasion died of hemoptysis. SABR with 70 Gy in 10 fractions appears to achieve excellent local control and acceptable toxicity for clinically challenging cases with improved tolerance of the chest wall and brachial plexus as compared with 50 Gy in 4 fractions. This regimen may not be suitable in patients with tumor invading critical central structures. More studies are needed to validate our conclusions. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Anti-oxidant effect of bergamot polyphenolic fraction counteracts doxorubicin-induced cardiomyopathy: Role of autophagy and c-kitposCD45negCD31neg cardiac stem cell activation.

PubMed

Carresi, Cristina; Musolino, Vincenzo; Gliozzi, Micaela; Maiuolo, Jessica; Mollace, Rocco; Nucera, Saverio; Maretta, Alessia; Sergi, Domenico; Muscoli, Saverio; Gratteri, Santo; Palma, Ernesto; Bosco, Francesca; Giancotta, Caterina; Muscoli, Carolina; Marino, Fabiola; Aquila, Iolanda; Torella, Daniele; Romeo, Franco; Mollace, Vincenzo

2018-04-12

Doxorubicin (DOXO) is one of the most widely used antineoplastic drugs. Despite its highly beneficial effects against several malignancies, the clinical use of DOXO is often associated to cardiomyopathy that leads to congestive heart failure. Here we investigated the antioxidant and cardioprotective effects of a polyphenol-rich fraction of citrus bergamot (BPF), in DOXO-induced cardiac damage in rats. Moreover, we evaluated the effect of BPF on cardiomyocyte survival and resident endogenous cardiac stem/progenitor cell (eCSC) activation. Adult male Wistar rats were i.p. injected with saline (serving as controls, CTRL, n = 10), BPF (20 mg/kg daily for 14 consecutive days, n = 10), DOXO (6 doses of 2,5 mg/Kg from day 1 to day 14, n = 10), and DOXO + BPF (n = 10). Animals were then sacrificed 7 days later (i.e., at 21 days). DOXO administration reduced cardiac function at 21 days, an adverse effect significantly attenuated in animals receiving DOXO + BPF. No changes were detected in rats receiving just saline or BPF alone. The cardioprotective effect of BPF on DOXO acute toxicity was also associated with a significant antioxidant effect coupled with protective autophagy restoration, and attenuation of cardiomyocyte apoptosis and reactive hypertrophy. Finally, treatment of rats with BPF prevented eCSCs attrition by DOXO which was followed by a limited but significant increase of newly-formed BrdU + cardiomyocytes. In conclusion, BPF reduces DOXO-induced cardiotoxicity by counteracting reactive oxygen species (ROS) overproduction, thereby restoring protective autophagy and attenuating cardiomyocyte apoptosis and pathologic remodeling. This beneficial effects on the early toxicity of DOXO is associated with enhanced CSCs survival and regenerative potential. Overall these data point to a potential clinical role by diet supplementation with polyphenol-rich fraction of citrus bergamot in counteracting antracycline-induced cardiomyopathy. Copyright © 2018. Published by Elsevier Ltd.

Proteomic analysis of acquired tamoxifen resistance in MCF-7 cells reveals expression signatures associated with enhanced migration

PubMed Central

2012-01-01

Introduction Acquired tamoxifen resistance involves complex signaling events that are not yet fully understood. Successful therapeutic intervention to delay the onset of hormone resistance depends critically on mechanistic elucidation of viable molecular targets associated with hormone resistance. This study was undertaken to investigate the global proteomic alterations in a tamoxifen resistant MCF-7 breast cancer cell line obtained by long term treatment of the wild type MCF-7 cell line with 4-hydroxytamoxifen (4-OH Tam). Methods We cultured MCF-7 cells with 4-OH Tam over a period of 12 months to obtain the resistant cell line. A gel-free, quantitative proteomic method was used to identify and quantify the proteome of the resistant cell line. Nano-flow high-performance liquid chromatography coupled to high resolution Fourier transform mass spectrometry was used to analyze fractionated peptide mixtures that were isobarically labeled from the resistant and control cell lysates. Real time quantitative PCR and Western blots were used to verify selected proteomic changes. Lentiviral vector transduction was used to generate MCF-7 cells stably expressing S100P. Online pathway analysis was performed to assess proteomic signatures in tamoxifen resistance. Survival analysis was done to evaluate clinical relevance of altered proteomic expressions. Results Quantitative proteomic analysis revealed a wide breadth of signaling events during transition to acquired tamoxifen resistance. A total of 629 proteins were found significantly changed with 364 up-regulated and 265 down-regulated. Collectively, these changes demonstrated the suppressed state of estrogen receptor (ER) and ER-regulated genes, activated survival signaling and increased migratory capacity of the resistant cell line. The protein S100P was found to play a critical role in conferring tamoxifen resistance and enhanced cell motility. Conclusions Our data demonstrate that the adaptive changes in the proteome of tamoxifen resistant breast cancer cells are characterized by down-regulated ER signaling, activation of alternative survival pathways, and enhanced cell motility through regulation of the actin cytoskeleton dynamics. Evidence also emerged that S100P mediates acquired tamoxifen resistance and migration capacity. PMID:22417809

Osthole induces G2/M cell cycle arrest and apoptosis in human hepatocellular carcinoma HepG2 cells.

PubMed

Chao, Xu; Zhou, Xiaojun; Zheng, Gang; Dong, Changhu; Zhang, Wei; Song, Xiaomei; Jin, Tianbo

2014-05-01

Osthole [7-methoxy-8-(3-methyl-2-butenyl) coumarin] isolated from the fruit of Cnidium monnieri (L.) Cuss, one of the commonly used Chinese medicines listed in the Shennong's Classic of Materia Medica in the Han Dynasty, had remarkable antiproliferative activity against human hepatocellular carcinoma HepG2 cells in culture. This study evaluated the effects of osthole on cell growth, nuclear morphology, cell cycle distribution, and expression of apoptosis-related proteins in HepG2 cells. Cytotoxic activity of osthole was determined by the MTT assay at various concentrations ranging from 0.004 to 1.0 µmol/ml in HepG2 cells. Cell morphology was assessed by Hoechst staining and fluorescence microscopy. Apoptosis and cell-cycle distribution was determined by annexin V staining and flow cytometry. Apoptotic protein levels were assessed by Western blot. Osthole exhibited significant inhibition of the survival of HepG2 cells and the half inhibitory concentration (IC₅₀) values were 0.186, 0.158 and 0.123 µmol/ml at 24, 48 and 72 h, respectively. Cells treated with osthole at concentrations of 0, 0.004, 0.02, 0.1 and 0.5 μmol/ml showed a statistically significant increase in the G2/M fraction accompanied by a decrease in the G0/G1 fraction. The increase of apoptosis induced by osthole was correlated with down-regulation expression of anti-apoptotic Bcl-2 protein and up-regulation expression of pro-apoptotic Bax and p53 proteins. Osthole had significant growth inhibitory activity and the pro-apoptotic effect of osthole is mediated through the activation of caspases and mitochondria in HepG2 cells. Results suggest that osthole has promising therapeutic potential against hepatocellular carcinoma.

Comparative Studies of the Proteome, Glycoproteome, and N-Glycome of Clear Cell Renal Cell Carcinoma Plasma before and after Curative Nephrectomy

PubMed Central

2015-01-01

Clear cell renal cell carcinoma is the most prevalent of all reported kidney cancer cases, and currently there are no markers for early diagnosis. This has stimulated great research interest recently because early detection of the disease can significantly improve the low survival rate. Combining the proteome, glycoproteome, and N-glycome data from clear cell renal cell carcinoma plasma has the potential of identifying candidate markers for early diagnosis and prognosis and/or to monitor disease recurrence. Here, we report on the utilization of a multi-dimensional fractionation approach (12P-M-LAC) and LC–MS/MS to comprehensively investigate clear cell renal cell carcinoma plasma collected before (disease) and after (non-disease) curative nephrectomy (n = 40). Proteins detected in the subproteomes were investigated via label-free quantification. Protein abundance analysis revealed a number of low-level proteins with significant differential expression levels in disease samples, including HSPG2, CD146, ECM1, SELL, SYNE1, and VCAM1. Importantly, we observed a strong correlation between differentially expressed proteins and clinical status of the patient. Investigation of the glycoproteome returned 13 candidate glycoproteins with significant differential M-LAC column binding. Qualitative analysis indicated that 62% of selected candidate glycoproteins showed higher levels (upregulation) in M-LAC bound fraction of disease samples. This observation was further confirmed by released N-glycans data in which 53% of identified N-glycans were present at different levels in plasma in the disease vs non-disease samples. This striking result demonstrates the potential for significant protein glycosylation alterations in clear cell renal cell carcinoma cancer plasma. With future validation in a larger cohort, information derived from this study may lead to the development of clear cell renal cell carcinoma candidate biomarkers. PMID:25184692

Detection of hypoxic fractions in murine tumors by comet assay: Comparison with other techniques

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hu, Q.; Kavanagh, M.C.; Newcombe, D.

1995-12-01

The alkaline comet assay was used to detect the hypoxic fractions of murine tumors. A total of four tumor types were tested using needle aspiration biopsies taken immediately after a radiation dose of 15 Gy. Initial studies confirmed that the normalized tail moment, a parameter reflecting single-strand DNA breaks induced by the radiation, was linearly related to radiation dose. Further, it was shown that for a mixed population (1:1) of cells irradiated under air-breathing or hypoxic conditions, the histogram of normal tail moment values obtained from analyzing 400 cells in the population had a double peak which, when fitted withmore » two Gaussian distributions, gave a good estimate of the proportion of the two subpopulations. For the four tumor types, the means of the calculated hypoxic fractions from four or five individual tumors were 0.15 {+-} 0.04 for B16F1, 0.08 {+-} 0.04 for KHT-LP1, 0.17 {+-} 0.04 for RIF-1 and 0.04 {+-} 0.01 for SCCVII. Analysis of variance showed that the hypoxic fraction in KHT-LP1 tumors is significantly lower than those of the other three tumors (P = 0.026) but that there is no significant difference in hypoxic fraction between B16F1, RIF-1 and SCCVII tumors (P = 0.574). Results from multiple samples taken from each of five RIF-1 tumors showed that the intertumor heterogeneity of hypoxic fractions was greater than that within the same tumor. The mean hypoxic fraction obtained using the comet assay for the four tumor types was compared with the hypoxic fraction determined by the clonogenic assay, or median pO{sub 2} values, or [{sup 3}H]misonidazole binding in the same tumor types. The values of hypoxic fraction obtained with the comet assay were two to four times lower than those measured by the paired survival method. Preliminary results obtained with a dose of 5 Gy were consistent with those obtained using 15 Gy. These results suggest the further development of the comet assay for clinical studies. 21 refs., 7 figs., 5 tabs.« less

Hypofractionated Image-guided Radiation Therapy (3Gy/fraction) in Patients Affected by Inoperable Advanced-stage Non-small Cell Lung Cancer After Long-term Follow-up.

PubMed

Agolli, Linda; Valeriani, Maurizio; Bracci, Stefano; Nicosia, Luca; DE Sanctis, Vitaliana; Enrici, Riccardo Maurizi; Osti, Mattia Falchetto

2015-10-01

We conducted long-term follow-up analysis of the outcomes for patients affected by advanced-stage non-small cell lung cancer (NSCLC) treated with hypofractionated radiotherapy (RT). Sixty patients with advanced-stage NSCLC (IIIA-IV) treated with hypofractionated radiotherapy (60Gy/20 fractions) were analyzed. Radiation was delivered using an image-guided RT technique to verify the correct position. Toxicities were graded according to the Common Toxicity Criteria for Adverse Effects v4.0 scale. Overall, six patients achieved a complete response and 46 patients had a partial response (tumor response rate 86%). After a median follow-up of 30 months, locoregional progression occurred in 23 patients and distant progression occurred in 38. The 1-year and 2-years overall survival were 57% and 40%, respectively. The 1-year and 2-years progression-free survival (PFS) were 47.1% and 33.5%, respectively. The median duration of OS and PFS was 13 months and 12 months, respectively. The 2-year local PFS and metastases-free survival (MFS) were 53% and 40.3%, respectively. On univariate analysis, the T-size (≥5 cm), and type of response to RT (non-response/progressive disease) were significantly associated with worse OS. Type of response was identified as significant prognostic factors for PFS (p<0.01) local PFS (p=0.015) and MFS (p<0.01). Acute grade 3 esophagitis and pneumonitis occurred in three patients (5%) and four patients (6%), respectively. Late grade 3 esophagitis and pneumonitis occurred in 2% (one patient) and 3% (two patients), respectively. No patient experienced grade 4 acute or late RT-related toxicities. Hypofractionated RT offers good disease control for patients with advanced-stage NSCLC with acceptable toxicity rates. Phase III randomized trials are necessary to compare hypofractionated RT with conventional RT. Copyright© 2015 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

Protocol for the CONVERT trial-Concurrent ONce-daily VErsus twice-daily RadioTherapy: an international 2-arm randomised controlled trial of concurrent chemoradiotherapy comparing twice-daily and once-daily radiotherapy schedules in patients with limited stage small cell lung cancer (LS-SCLC) and good performance status.

PubMed

Faivre-Finn, Corinne; Falk, Sally; Ashcroft, Linda; Bewley, Michelle; Lorigan, Paul; Wilson, Elena; Groom, Nicki; Snee, Michael; Fournel, Pierre; Cardenal, Felipe; Bezjak, Andrea; Blackhall, Fiona

2016-01-20

Concurrent ONce-daily VErsus twice-daily RadioTherapy (CONVERT) is the only multicentre, international, randomised, phase III trial open in Europe and Canada looking at optimisation of chemoradiotherapy (RT) in limited stage small cell lung cancer (LS-SCLC). Following on from the Turrisi trial of once-daily versus twice-daily (BD) concurrent chemoradiotherapy, there is a real need for a new phase III trial using modern conformal RT techniques and investigating higher once-daily radiation dose. This trial has the potential to define a new standard chemo-RT regimen for patients with LS-SCLC and good performance status. 447 patients with histologically or cytologically proven diagnosis of SCLC were recruited from 74 centres in eight countries between 2008 and 2013. Patients were randomised to receive either concurrent twice-daily RT(45 Gy in 30 twice-daily fractions over 3 weeks) or concurrent once-daily RT(66 Gy in 33 once-daily fractions over 6.5 weeks) both starting on day 22 of cycle 1. Patients are followed up until death. The primary end point of the study is overall survival and secondary end points include local progression-free survival, metastasis-free survival, acute and late toxicity based on the Common Terminology Criteria for Adverse Events V.3.0, chemotherapy and RTdose intensity. The trial received ethical approval from NRES Committee North West-Greater Manchester Central (07/H1008/229). There is a trial steering committee, including independent members and an independent data monitoring committee. Results will be published in a peer-reviewed journal and presented at international conferences. ISRCTN91927162; Pre-results. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Adaptive/nonadaptive proton radiation planning and outcomes in a phase II trial for locally advanced non-small cell lung cancer.

PubMed

Koay, Eugene J; Lege, David; Mohan, Radhe; Komaki, Ritsuko; Cox, James D; Chang, Joe Y

2012-12-01

To analyze dosimetric variables and outcomes after adaptive replanning of radiation therapy during concurrent high-dose protons and chemotherapy for locally advanced non-small cell lung cancer (NSCLC). Nine of 44 patients with stage III NSCLC in a prospective phase II trial of concurrent paclitaxel/carboplatin with proton radiation [74 Gy(RBE) in 37 fractions] had modifications to their original treatment plans after re-evaluation revealed changes that would compromise coverage of the target volume or violate dose constraints; plans for the other 35 patients were not changed. We compared patients with adaptive plans with those with nonadaptive plans in terms of dosimetry and outcomes. At a median follow-up of 21.2 months (median overall survival, 29.6 months), no differences were found in local, regional, or distant failure or overall survival between groups. Adaptive planning was used more often for large tumors that shrank to a greater extent (median, 107.1 cm(3) adaptive and 86.4 cm(3) nonadaptive; median changes in volume, 25.3% adaptive and 1.2% nonadaptive; P<.01). The median number of fractions delivered using adaptive planning was 13 (range, 4-22). Adaptive planning generally improved sparing of the esophagus (median absolute decrease in V(70), 1.8%; range, 0%-22.9%) and spinal cord (median absolute change in maximum dose, 3.7 Gy; range, 0-13.8 Gy). Without adaptive replanning, target coverage would have been compromised in 2 cases (57% and 82% coverage without adaptation vs 100% for both with adaptation); neither patient experienced local failure. Radiation-related grade 3 toxicity rates were similar between groups. Adaptive planning can reduce normal tissue doses and prevent target misses, particularly for patients with large tumors that shrink substantially during therapy. Adaptive plans seem to have acceptable toxicity and achieve similar local, regional, and distant control and overall survival, even in patients with larger tumors, vs nonadaptive plans. Copyright © 2012 Elsevier Inc. All rights reserved.

Stereotactic body radiotherapy for stage I non-small-cell lung cancer using higher doses for larger tumors: results of the second study.

PubMed

Miyakawa, Akifumi; Shibamoto, Yuta; Baba, Fumiya; Manabe, Yoshihiko; Murai, Taro; Sugie, Chikao; Yanagi, Takeshi; Takaoka, Taiki

2017-09-11

Efficacy of stereotactic body radiotherapy (SBRT) in stage I non-small-cell lung cancer (NSCLC) has almost been established. In Japan, the protocol of 48 Gy in 4 fractions over 4 days has been most often employed, but higher doses may be necessary to control large tumors. Previously, we conducted a clinical study using SBRT for stage I NSCLC employing different doses depending on tumor diameter, which was closed in 2008. Thereafter, a new study employing higher doses has been conducted, which is reported here. The purpose of this study was to review the safety and effectiveness of the higher doses. We escalated the total dose for the improvement of local control for large tumors. In this study, 71 patients underwent SBRT between December 2008 and April 2014. Isocenter doses of 48, 50, and 52 Gy were administered for tumors with a longest diameter of < 1.5 cm, 1.5-3 cm, and > 3 cm, respectively. It was recommended to cover 95% of the PTV with at least 90% of the isocenter dose, and in all but one cases, 95% of the PTV received at least 80% of the prescribed dose. Treatments were delivered in 4 fractions, giving 2 fractions per week. SBRT was performed with 6-MV photons using 4 non-coplanar and 3 coplanar beams. The median follow-up period was 44 months for all patients and 61 months for living patients. Overall survival (OS) was 65%, progression-free survival (PFS) was 55%, and cumulative incidence of local recurrence (LR) was 15% at 5 years. The 5-year OS was 69% for 57 stage IA patients and 53% for 14 stage IB patients (p = 0.44). The 5-year PFS was 55 and 54%, respectively (p = 0.98). The 5-year cumulative incidence of LR was 11 and 31%, respectively (p = 0.09). The cumulative incidence of Grade ≥ 2 radiation pneumonitis was 25%. Our newer SBRT study yielded reasonable local control and overall survival and acceptable toxicity, but escalating the total dose did not lead to improved outcomes. UMIN000027231 , registered on 3 May 2017. Retrospectively registered.

Effect of Smoking During Radiotherapy, Respiratory Insufficiency, and Hemoglobin Levels on Outcome in Patients Irradiated for Non-Small-Cell Lung Cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rades, Dirk; Setter, Cornelia M.S.; Schild, Steven E.

Purpose: To investigate the effect of smoking during radiotherapy (RT), respiratory insufficiency before RT, hemoglobin levels during RT, and additional factors on overall survival, locoregional control (LRC), and metastasis-free survival in non-small-cell lung cancer patients. Methods and Materials: The following factors were investigated in 181 patients who underwent RT for non-small-cell lung cancer: age, gender, Karnofsky performance score, histologic type, grade, T/N stage, American Joint Committee on Cancer stage, surgery, chemotherapy, respiratory insufficiency before RT, pack-years, smoking during RT, and hemoglobin levels during RT. Additionally, in the 129 patients who did not undergo surgery, the effect of the equivalent dosemore » in 2-Gy fractions (EQD2) (<60 Gy vs. 60 Gy vs. >60 Gy) on outcome was investigated. Results: On multivariate analysis, improved overall survival was associated with a lower T stage (p = 0.004), lower N stage (p 0.040), surgery (p = 0.010), and no respiratory insufficiency (p = 0.023). A Karnofsky performance score >70 achieved borderline significance (p = 0.056). Improved LRC was associated with a lower T stage (p = 0.007) and no smoking during RT (p = 0.029). Improved metastasis-free survival was associated with lower T stage (p < 0.001) and lower N stage (p < 0.001). In those patients who did not undergo surgery, an EQD2 of {>=}60 Gy was associated with a better outcome than an EQD2 of <60 Gy. Furthermore, an EQD2 >60 Gy resulted in better LRC than did an EQD2 of {<=}60 Gy. Conclusions: Smoking during RT had a significant effect on LRC, but we did not find that hemoglobin levels or respiratory insufficiency significantly affected LRC or metastasis-free survival in our patient population. Furthermore, our data suggest a dose-effect relationship in those patients who did not undergo surgery.« less

Combination therapy of intravenously injected microglia and radiotherapy prolongs survival in a rat model of spontaneous malignant glioma.

PubMed

Okonogi, Noriyuki; Suzuki, Yoshiyuki; Sato, Hiro; Oike, Takahiro; Yoshimoto, Yuya; Mimura, Kousaku; Noda, Shin-Ei; Okamoto, Masahiko; Tamaki, Tomoaki; Morokoshi, Yukie; Hasegawa, Sumitaka; Ohgaki, Hiroko; Yokoo, Hideaki; Nakano, Takashi

2018-06-18

The aim of this study was to investigate the efficacy of combination therapy with intravenously injected microglia (MI) and radiotherapy (RT) for rat malignant glioma. Transgenic rats expressing v-erbB and spontaneously developing malignant glioma were used. The rats were divided into four groups: control (n = 19), RT alone (n = 10), MI alone (n = 9), and combination of MI and RT (MI+RT) (n = 10). Cranial X-ray irradiation (8 Gy per fraction; once per week) was performed at 50 and 51 weeks of age. Cultured rat microglial cells (5 × 10 6 cells/rat) were intravenously injected via the tail vein within 30 minutes after RT. No evidence of side effects including thrombosis or graft-versus-host disease was noted. Rats treated with RT alone, MI alone, MI+RT, and control survived 60.9, 56.3, 66.0, and 56.1 weeks, respectively. The survival period of MI+RT was significantly longer than that of control (p = 0.014), MI alone (p = 0.027), and RT alone (p = 0.049). Immunohistochemical analysis showed significantly higher number of tumor-infiltrated microglia in the RT alone (p = 0.041) and MI+RT groups (p = 0.014) compared with the control. Significantly more CD8-positive lymphocytes were observed in the MI+RT group (p = 0.049) compared with the control. A positive correlation was found between the number of microglia and CD8-positive lymphocytes (R 2 = 0.556). A positive correlation was also found between CD8-positive lymphocytes and survival periods (R 2 = 0.460). MI+RT increased infiltrated microglia and CD8-positive T cells and prolonged the survival in transgenic rats spontaneously developing malignant glioma. Combined immunocellular therapy and RT may provide a novel treatment strategy for malignant glioma. Copyright © 2018. Published by Elsevier Inc.

MO-FG-BRA-05: Dosimetric and Radiobiological Validation of Respiratory Gating in Conventional and Hypofractionated Radiotherapy of the Lung: Effect of Dose, Dose Rate, Gating Window and Breathing Pattern

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cervino, L; Soultan, D; Pettersson, N

2016-06-15

Purpose: to evaluate the dosimetric and radiobiological consequences from having different gating windows, dose rates, and breathing patterns in gated VMAT lung radiotherapy. Methods: A novel 3D-printed moving phantom with central high and peripheral low tracer uptake regions was 4D FDG-PET/CT-scanned using ideal, patient-specific regular, and irregular breathing patterns. A scan of the stationary phantom was obtained as a reference. Target volumes corresponding to different uptake regions were delineated. Simultaneous integrated boost (SIB) 6 MV VMAT plans were produced for conventional and hypofractionated radiotherapy, using 30–70 and 100% cycle gating scenarios. Prescribed doses were 200 cGy with SIB to 240more » cGy to high uptake volume for conventional, and 800 with SIB to 900 cGy for hypofractionated plans. Dose rates of 600 MU/min (conventional and hypofractionated) and flattening filter free 1400 MU/min (hypofractionated) were used. Ion chamber measurements were performed to verify delivered doses. Vials with A549 cells placed in locations matching ion chamber measurements were irradiated using the same plans to measure clonogenic survival. Differences in survival for the different doses, dose rates, gating windows, and breathing patterns were analyzed. Results: Ion chamber measurements agreed within 3% of the planned dose, for all locations, breathing patterns and gating windows. Cell survival depended on dose alone, and not on gating window, breathing pattern, MU rate, or delivery time. The surviving fraction varied from approximately 40% at 2Gy to 1% for 9 Gy and was within statistical uncertainty relative to that observed for the stationary phantom. Conclusions: Use of gated VMAT in PET-driven SIB radiotherapy was validated using ion chamber measurements and cell survival assays for conventional and hypofractionated radiotherapy.« less

SK4 channels modulate Ca2+ signalling and cell cycle progression in murine breast cancer.

PubMed

Steudel, Friederike A; Mohr, Corinna J; Stegen, Benjamin; Nguyen, Hoang Y; Barnert, Andrea; Steinle, Marc; Beer-Hammer, Sandra; Koch, Pierre; Lo, Wing-Yee; Schroth, Werner; Hoppe, Reiner; Brauch, Hiltrud; Ruth, Peter; Huber, Stephan M; Lukowski, Robert

2017-09-01

Oncogenic signalling via Ca 2+ -activated K + channels of intermediate conductance (SK4, also known as K Ca 3.1 or IK) has been implicated in different cancer entities including breast cancer. Yet, the role of endogenous SK4 channels for tumorigenesis is unclear. Herein, we generated SK4-negative tumours by crossing SK4-deficient (SK4 KO) mice to the polyoma middle T-antigen (PyMT) and epidermal growth factor receptor 2 (cNeu) breast cancer models in which oncogene expression is driven by the retroviral promoter MMTV. Survival parameters and tumour progression were studied in cancer-prone SK4 KO in comparison with wild-type (WT) mice and in a syngeneic orthotopic mouse model following transplantation of SK4-negative or WT tumour cells. SK4 activity was modulated by genetic or pharmacological means using the SK4 inhibitor TRAM-34 in order to establish the role of breast tumour SK4 for cell growth, electrophysiological signalling, and [Ca 2+ ] i oscillations. Ablation of SK4 and TRAM-34 treatment reduced the SK4-generated current fraction, growth factor-dependent Ca 2+ entry, cell cycle progression and the proliferation rate of MMTV-PyMT tumour cells. In vivo, PyMT oncogene-driven tumorigenesis was only marginally affected by the global lack of SK4, whereas tumour progression was significantly delayed after orthotopic implantation of MMTV-PyMT SK4 KO breast tumour cells. However, overall survival and progression-free survival time in the MMTV-cNeu mouse model were significantly extended in the absence of SK4. Collectively, our data from murine breast cancer models indicate that SK4 activity is crucial for cell cycle control. Thus, the modulation of this channel should be further investigated towards a potential improvement of existing antitumour strategies in human breast cancer. © 2017 The Authors. Published by FEBS Press and John Wiley & Sons Ltd.

Mutagenic effects of a single and an exact number of alpha particles in mammalian cells

NASA Technical Reports Server (NTRS)

Hei, T. K.; Wu, L. J.; Liu, S. X.; Vannais, D.; Waldren, C. A.; Randers-Pehrson, G.

1997-01-01

One of the main uncertainties in risk estimation for environmental radon exposure using lung cancer data from underground miners is the extrapolation from high- to low-dose exposure where multiple traversal is extremely rare. The biological effects of a single alpha particle are currently unknown. Using the recently available microbeam source at the Radiological Research Accelerator Facility at Columbia University, we examined the frequencies and molecular spectrum of S1- mutants induced in human-hamster hybrid (A(L)) cells by either a single or an exact number of alpha particles. Exponentially growing cells were stained briefly with a nontoxic concentration of Hoechst dye for image analysis, and the location of individual cells was computer-monitored. The nucleus of each cell was irradiated with either 1,2,4, or 8 alpha particles at a linear energy transfer of 90 keV/microm consistent with the energy spectrum of domestic radon exposure. Although single-particle traversal was only slightly cytotoxic to A(L) cells (survival fraction approximately 0.82), it was highly mutagenic, and the induced mutant fraction averaged 110 mutants per 10(5) survivors. In addition, both toxicity and mutant induction were dose-dependent. Multiplex PCR analysis of mutant DNA showed that the proportion of mutants with multilocus deletions increased with the number of particle traversals. These data provide direct evidence that a single a particle traversing a nucleus will have a high probability of resulting in a mutation and highlight the need for radiation protection at low doses.

Mutagenic effects of a single and an exact number of alpha particles in mammalian cells.

PubMed

Hei, T K; Wu, L J; Liu, S X; Vannais, D; Waldren, C A; Randers-Pehrson, G

1997-04-15

One of the main uncertainties in risk estimation for environmental radon exposure using lung cancer data from underground miners is the extrapolation from high- to low-dose exposure where multiple traversal is extremely rare. The biological effects of a single alpha particle are currently unknown. Using the recently available microbeam source at the Radiological Research Accelerator Facility at Columbia University, we examined the frequencies and molecular spectrum of S1- mutants induced in human-hamster hybrid (A(L)) cells by either a single or an exact number of alpha particles. Exponentially growing cells were stained briefly with a nontoxic concentration of Hoechst dye for image analysis, and the location of individual cells was computer-monitored. The nucleus of each cell was irradiated with either 1,2,4, or 8 alpha particles at a linear energy transfer of 90 keV/microm consistent with the energy spectrum of domestic radon exposure. Although single-particle traversal was only slightly cytotoxic to A(L) cells (survival fraction approximately 0.82), it was highly mutagenic, and the induced mutant fraction averaged 110 mutants per 10(5) survivors. In addition, both toxicity and mutant induction were dose-dependent. Multiplex PCR analysis of mutant DNA showed that the proportion of mutants with multilocus deletions increased with the number of particle traversals. These data provide direct evidence that a single a particle traversing a nucleus will have a high probability of resulting in a mutation and highlight the need for radiation protection at low doses.

Cell cycle arrest in the jewel wasp Nasonia vitripennis in larval diapause.

PubMed

Shimizu, Yuta; Mukai, Ayumu; Goto, Shin G

2018-04-01

Insects enter diapause to synchronise their life cycle with biotic and abiotic environmental conditions favourable for their development, reproduction, and survival. One of the most noticeable characteristics of diapause is the blockage of ontogeny. Although this blockage should occur with the cessation of cellular proliferation, i.e. cell cycle arrest, it was confirmed only in a few insect species and information on the molecular pathways involved in cell cycle arrest is limited. In the present study, we investigated developmental and cell cycle arrest in diapause larvae of the jewel wasp Nasonia vitripennis. Developmental and cell cycle arrest occur in the early fourth instar larval stage of N. vitripennis under short days. By entering diapause, the S fraction of the cell cycle disappears and approximately 80% and 20% of cells arrest their cell cycle in the G0/G1 and G2 phases, respectively. We further investigated expression of cell cycle regulatory genes and some housekeeping genes to dissect molecular mechanisms underlying the cell cycle arrest. Copyright © 2016 Elsevier Ltd. All rights reserved.

Is Intermediate Radiation Dose Escalation With Concurrent Chemotherapy for Stage III Non–Small-Cell Lung Cancer Beneficial? A Multi-Institutional Propensity Score Matched Analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rodrigues, George, E-mail: george.rodrigues@lhsc.on.ca; Oberije, Cary; Senan, Suresh

2015-01-01

Purpose: The clinical benefits and risks of dose escalation (DE) for stage III non–small-cell lung cancer (NSCLC) remain uncertain despite the results from Radiation Therapy Oncology Group (RTOG) protocol 0617. There is significant heterogeneity of practice, with many clinicians prescribing intermediate dose levels between the 0617 study arms of 60 and 74 Gy. This study investigated whether this strategy is associated with any survival benefits/risks by analyzing a large multi-institutional database. Methods and Materials: An individual patient database of stage III NSCLC patients treated with radical intent concurrent chemoradiation therapy was created (13 institutions, n=1274 patients). Patients were divided into 2more » groups based on tumor Biological Effective Dose at 10 Gy (BED 10): those receiving standard dose (SD; n=552), consisting of 72Gy ≤ BED 10 ≤ 76.8 Gy (eg 60-64 Gy/30-32 fractions [fr]), and those receiving intermediate dose (ID; n=497), consisting of 76.8Gy < BED 10 < 100.8 Gy (eg >64 Gy/32 fr and <74 Gy/37 fr), with lower-dose patients (n=225) excluded from consideration. Patients were then matched using propensity scores, leading to 2 matched groups of 196 patients. Outcomes were compared using various statistics including interquartile range (IQR), Kaplan-Meier curves, and adjusted Cox regression analysis. Results: Matched groups were found to be balanced except for N stage (more N3 disease in SD), median treatment year (SD in 2003; ID in 2007), platinum and taxane chemotherapy (SD in 28%; ID in 39%), and median follow-up (SD were 89 months; ID were 40 months). Median dose fractionation was 60 Gy/30 fr in SD (BED 10 IQR: 72.0-75.5 Gy) and 66 Gy/33 fr (BED 10 IQR: 78.6-79.2 Gy) in ID. Survival curves for SD and ID matched cohorts were statistically similar (P=.27); however, a nonstatistically significant trend toward better survival for ID was observed after 15 months (median survival SD: 19.3 months; ID: 21.0 months). There was an increase in grades III to V lung toxicity associated with ID (13.0% vs 4.9%, respectively). Conclusions: No significant overall survival benefits were found with intermediate DE; however, more grade III or greater lung toxicity was observed. The separation of survival curves after 15 months of follow-up suggests that a small overall survival improvement associated with intermediate DE cannot be excluded.« less

IDEAL-CRT: A Phase 1/2 Trial of Isotoxic Dose-Escalated Radiation Therapy and Concurrent Chemotherapy in Patients With Stage II/III Non-Small Cell Lung Cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Landau, David B., E-mail: david.landau@kcl.ac.uk; Hughes, Laura; Baker, Angela

2016-08-01

Purpose: To report toxicity and early survival data for IDEAL-CRT, a trial of dose-escalated concurrent chemoradiotherapy (CRT) for non-small cell lung cancer. Patients and Methods: Patients received tumor doses of 63 to 73 Gy in 30 once-daily fractions over 6 weeks with 2 concurrent cycles of cisplatin and vinorelbine. They were assigned to 1 of 2 groups according to esophageal dose. In group 1, tumor doses were determined by an experimental constraint on maximum esophageal dose, which was escalated following a 6 + 6 design from 65 Gy through 68 Gy to 71 Gy, allowing an esophageal maximum tolerated dose to be determined from early and late toxicities. Tumormore » doses for group 2 patients were determined by other tissue constraints, often lung. Overall survival, progression-free survival, tumor response, and toxicity were evaluated for both groups combined. Results: Eight centers recruited 84 patients: 13, 12, and 10, respectively, in the 65-Gy, 68-Gy, and 71-Gy cohorts of group 1; and 49 in group 2. The mean prescribed tumor dose was 67.7 Gy. Five grade 3 esophagitis and 3 grade 3 pneumonitis events were observed across both groups. After 1 fatal esophageal perforation in the 71-Gy cohort, 68 Gy was declared the esophageal maximum tolerated dose. With a median follow-up of 35 months, median overall survival was 36.9 months, and overall survival and progression-free survival were 87.8% and 72.0%, respectively, at 1 year and 68.0% and 48.5% at 2 years. Conclusions: IDEAL-CRT achieved significant treatment intensification with acceptable toxicity and promising survival. The isotoxic design allowed the esophageal maximum tolerated dose to be identified from relatively few patients.« less

Influence of biochar application on potassium-solubilizing Bacillus mucilaginosus as potential biofertilizer.

PubMed

Liu, Sainan; Tang, Wenzhu; Yang, Fan; Meng, Jun; Chen, Wenfu; Li, Xianzhen

2017-01-02

Biochar can enhance soil fertility to increase agricultural productivity, whereas its improvement in soil microbial activity is still unclear. In this article, the influence of biochar on the cell growth and the potassium-solubilizing activity of Bacillus mucilaginosus AS1153 was examined. The impact on cell growth is related to the biochar-derived feedstocks and the particle size of biochar. Both intrinsic features and inner component fraction can promote the cell growth of B. mucilaginosus AS1153. The potassium-solubilizing activity was increased by 80% when B. mucilaginosus was incubated in conjunction with the biochar derived from corn stover. The survival time of B. mucilaginosus also was prolonged by adsorption in biochar. The experimental results suggested that the biochar containing B. mucilaginosus could be used as a potential biofertilizer to sustain crop production.

Methods for assisting recovery of damaged brain and spinal cord using arrays of X-Ray microplanar beams

DOEpatents

Dilmanian, F. Avraham; McDonald, III, John W.

2007-12-04

A method of assisting recovery of an injury site of brain or spinal cord injury includes providing a therapeutic dose of X-ray radiation to the injury site through an array of parallel microplanar beams. The dose at least temporarily removes regeneration inhibitors from the irradiated regions. Substantially unirradiated cells surviving between the microplanar beams migrate to the in-beam irradiated portion and assist in recovery. The dose may be administered in dose fractions over several sessions, separated in time, using angle-variable intersecting microbeam arrays (AVIMA). Additional doses may be administered by varying the orientation of the microplanar beams. The method may be enhanced by injecting stem cells into the injury site.

Methods for assisting recovery of damaged brain and spinal cord using arrays of X-ray microplanar beams

DOEpatents

Dilmanian, F. Avraham; McDonald, III, John W.

2007-01-02

A method of assisting recovery of an injury site of brain or spinal cord injury includes providing a therapeutic dose of X-ray radiation to the injury site through an array of parallel microplanar beams. The dose at least temporarily removes regeneration inhibitors from the irradiated regions. Substantially unirradiated cells surviving between the microplanar beams migrate to the in-beam irradiated portion and assist in recovery. The dose may be administered in dose fractions over several sessions, separated in time, using angle-variable intersecting microbeam arrays (AVIMA). Additional doses may be administered by varying the orientation of the microplanar beams. The method may be enhanced by injecting stem cells into the injury site.

Long-Term Disease-Free Survival of Non-Metastatic Breast Cancer Patients in Iran: A Survival Model with Competing Risks Taking Cure Fraction and Frailty into Account

PubMed

Ghavami, Vahid; Mahmoudi, Mahmood; Rahimi Foroushani, Abbas; Baghishani, Hossein; Homaei Shandiz, Fatemeh; Yaseri, Mehdi

2017-10-26

Introduction: Survival modeling is a very important tool to detect risk factors and provide a basis for health care planning. However, cancer data may have properties leading to distorted results with routine methods. Therefore, this study aimed to cover specific factors (competing risk, cure fraction and heterogeneity) with a real dataset of Iranian breast cancer patients using a competing risk-cure-frailty model. Materials and methods: For this historical cohort study, information for 550 Iranian breast cancer patients who underwent surgery for tumor removal from 2001 to 2007 and were followed up to March 2017, was analyzed using R 3.2 software. Results: In contrast to T-stage and N-stage, hormone receptor status did not have any significant effect on the cure fraction (long-term disease-free survival). However, T-stage, N-stage and hormone receptor status all had a significant effect on short-term disease-free survival so that the hazard of loco-regional relapse or distant metastasis in cases positive for a hormone receptor was only 0.3 times that for their negative hormone receptor counterparts. The likelihood of locoregional relapse in the first quartile of follow up was nearly twice that of other quartiles. The least cumulative incidence of time to locoregional relapse was for cases with a positive hormone receptor, low N stage and low T stage. The effect of frailty term was significant in this study and a model with frailty appeared more appropriate than a model without, based on the Akaike information criterion (AIC); values for the frailty model and one without the frailty parameter were 1370.39 and 1381.46, respectively. Conclusions: The data from this study indicate ae necessity to consider competing risk, cure fraction and heterogeneity in survival modeling. The competing risk-cure-frailty model can cover complex situations with survival data. Creative Commons Attribution License

ECT2 and RASAL2 mediate mesenchymal-amoeboid transition in human astrocytoma cells.

PubMed

Weeks, Adrienne; Okolowsky, Nadia; Golbourn, Brian; Ivanchuk, Stacey; Smith, Christian; Rutka, James T

2012-08-01

Malignant astrocytomas are highly invasive brain tumors. The Rho family of cytoskeletal GTPases are key regulators of astrocytoma migration and invasion; expression of the guanine nucleotide exchange factor ECT2 is elevated in primary astrocytomas and predicts both survival and malignancy. Mice bearing orthotopically implanted astrocytoma cells with diminished ECT2 levels following ECT2 knockdown exhibit longer survival. Although ECT2 is normally expressed in the nucleus, we show that ECT2 is aberrantly localized to the cytoplasm in both astrocytoma cell lines and primary human astrocytomas, and colocalizes with RAC1 and CDC42 at the leading edge of migrating astrocytoma cells. Inhibition of ECT2 expression by RNA interference resulted in decreased RAC1 and CDC42 activity, but no change in RHO activity, suggesting that ECT2 is capable of activating these pro-migratory Rho family members. ECT2 overexpression in astrocytoma cells resulted in a transition to an amoeboid phenotype that was abolished with the ROCK inhibitor, Y-27632. Cytoplasmic fractionation of astrocytoma cells followed by ECT2 immunoprecipitation and mass spectrometry were used to identify protein-binding partners that modulate the activity of ECT2 toward RAC1 and RHO/ROCK. We identified RASAL2 as an ECT2-interacting protein that regulates RHO activity in astrocytoma cells. RASAL2 knockdown leads to a conversion to an amoeboid phenotype. Our studies reveal that ECT2 has a novel role in mesenchymal-amoeboid transition in human astrocytoma cells. Copyright © 2012 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

Curcumin Induces Apoptosis in Human Colorectal Carcinoma (HCT-15) Cells by Regulating Expression of Prp4 and p53

PubMed Central

Shehzad, Adeeb; Lee, Jaetae; Huh, Tae-Lin; Lee, Young Sup

2013-01-01

Curcumin (diferuloylmethane), the yellow pigment of turmeric, is one of the most commonly used and extensively studied phytochemicals due to its pleiotropic effects in several human cancers. In the current study, the therapeutic efficacy of curcumin was investigated in human colorectal carcinoma HCT-15 cells. Curcumin inhibited HCT-15 cells proliferation and induced apoptosis in a dose- and time-dependent manner. Hoechst 33342 and DCFHDA staining revealed morphological and biochemical features of apoptosis as well as ROS generation in HCT-15 cells treated with 30 and 50 μM curcumin. Over-expression of pre-mRNA processing factor 4B (Prp4B) and p53 mutations have been reported as hallmarks of cancer cells. Western blot analysis revealed that curcumin treatment activated caspase-3 and decreased expression of p53 and Prp4B in a time-dependent manner. Transfection of HCT-15 cells with Prp4B clone perturbed the growth inhibition induced by 30 μM curcumin. Fractionation of cells revealed increased accumulation of Prp4B in the nucleus, following its translocation from the cytoplasm. To further evaluate the underlying mechanism and survival effect of Prp4B, we generated siRNA-Prp4B HCT15 clones. Knockdown of Prp4B with siRNA diminished the protective effects of Prp4B against curcumin-induced apoptosis. These results suggest a possible underlying molecular mechanism in which Prp4B over-expression and activity are closely associated with the survival and regulation of apoptotic events in human colon cancer HCT-15 cells. PMID:23686430

A branching process model for the analysis of abortive colony size distributions in carbon ion-irradiated normal human fibroblasts.

PubMed

Sakashita, Tetsuya; Hamada, Nobuyuki; Kawaguchi, Isao; Hara, Takamitsu; Kobayashi, Yasuhiko; Saito, Kimiaki

2014-05-01

A single cell can form a colony, and ionizing irradiation has long been known to reduce such a cellular clonogenic potential. Analysis of abortive colonies unable to continue to grow should provide important information on the reproductive cell death (RCD) following irradiation. Our previous analysis with a branching process model showed that the RCD in normal human fibroblasts can persist over 16 generations following irradiation with low linear energy transfer (LET) γ-rays. Here we further set out to evaluate the RCD persistency in abortive colonies arising from normal human fibroblasts exposed to high-LET carbon ions (18.3 MeV/u, 108 keV/µm). We found that the abortive colony size distribution determined by biological experiments follows a linear relationship on the log-log plot, and that the Monte Carlo simulation using the RCD probability estimated from such a linear relationship well simulates the experimentally determined surviving fraction and the relative biological effectiveness (RBE). We identified the short-term phase and long-term phase for the persistent RCD following carbon-ion irradiation, which were similar to those previously identified following γ-irradiation. Taken together, our results suggest that subsequent secondary or tertiary colony formation would be invaluable for understanding the long-lasting RCD. All together, our framework for analysis with a branching process model and a colony formation assay is applicable to determination of cellular responses to low- and high-LET radiation, and suggests that the long-lasting RCD is a pivotal determinant of the surviving fraction and the RBE.

A randomized phase III study between sequential versus simultaneous integrated boost intensity-modulated radiation therapy in nasopharyngeal carcinoma.

PubMed

Lertbutsayanukul, Chawalit; Prayongrat, Anussara; Kannarunimit, Danita; Chakkabat, Chakkapong; Netsawang, Buntipa; Kitpanit, Sarin

2018-05-01

This study was performed to compare the acute and late toxicities between sequential (SEQ) and simultaneous integrated boost (SIB) intensity-modulated radiotherapy (IMRT) in nasopharyngeal carcinoma (NPC). Stage I-IVB NPC patients were randomized to receive SEQ-IMRT or SIB-IMRT. SEQ-IMRT consisted of two plans: 2 Gy × 25 fractions to low-risk planning target volume (PTV) followed by a sequential boost (2 Gy × 10 fractions) to high-risk PTV, while SIB-IMRT treated low- and high-risk PTVs with doses of 56 and 70 Gy in 33 fractions. Toxicities and survival outcomes were analyzed. Between October 2010 and September 2015, of the 209 patients who completed treatment, 102 in the SEQ and 107 in the SIB arm were analyzed. The majority had undifferentiated squamous cell carcinoma (82%). Mucositis and dysphagia were the most common grade 3-5 acute toxicities. There were no statistically significant differences in the cumulative incidence of grade 3-4 acute toxicities between the two arms (59.8% in SEQ vs. 58.9% in SIB; P = 0.892). Common grade 3-4 late toxicities for SEQ and SIB included hearing loss (2.9 vs. 8.4%), temporal lobe injury (2.9 vs. 0.9%), cranial nerve injury (0 vs. 2.8%), and xerostomia (2 vs. 0.9%). With the median follow-up of 41 months, 3‑year progression-free and overall survival rates were 72.7 vs. 73.4% (P = 0.488) and 86.3 vs. 83.6% (P = 0.938), respectively. SEQ and SIB provide excellent survival outcomes with few late toxicities. According to our study, SIB with a satisfactory dose-volume constraint to nearby critical organs is the technique of choice for NPC treatment due to its convenience.

Clinical-Scale Cell-Surface-Marker Independent Acoustic Microfluidic Enrichment of Tumor Cells from Blood.

PubMed

Magnusson, Cecilia; Augustsson, Per; Lenshof, Andreas; Ceder, Yvonne; Laurell, Thomas; Lilja, Hans

2017-11-21

Enumeration of circulating tumor cells (CTCs) predicts overall survival and treatment response in metastatic cancer, but as many commercialized assays isolate CTCs positive for epithelial cell markers alone, CTCs with little or no epithelial cell adhesion molecule (EpCAM) expression stay undetected. Therefore, CTC enrichment and isolation by label-free methods based on biophysical rather than biochemical properties could provide a more representative spectrum of CTCs. Here, we report on a clinical-scale automated acoustic microfluidic platform processing 5 mL of erythrocyte-depleted paraformaldehyde (PFA)-fixed blood (diluted 1:2) at a flow rate of 75 μL/min, recovering 43/50 (86 ± 2.3%) breast cancer cell line cells (MCF7), with 0.11% cancer cell purity and 162-fold enrichment in close to 2 h based on intrinsic biophysical cell properties. Adjustments of the voltage settings aimed at higher cancer cell purity in the central outlet provided 0.72% cancer cell purity and 1445-fold enrichment that resulted in 62 ± 8.7% cancer cell recovery. Similar rates of cancer-cell recovery, cancer-cell purity, and fold-enrichment were seen with both prostate cancer (DU145, PC3) and breast cancer (MCF7) cell line cells. We identified eosinophil granulocytes as the predominant white blood cell (WBC) contaminant (85%) in the enriched cancer-cell fraction. Processing of viable cancer cells in erythrocyte-depleted blood provided slightly reduced results as to fixed cells (77% cancer cells in the enriched cancer cell fraction, with 0.2% WBC contamination). We demonstrate feasibility of enriching either PFA-fixed or viable cancer cells with a clinical-scale acoustic microfluidic platform that can be adjusted to meet requirements for either high cancer-cell recovery or higher purity and can process 5 mL blood samples in close to 2 h.

In vitro expansion of Lin+ and Lin- mononuclear cells from human peripheral blood

NASA Astrophysics Data System (ADS)

Norhaiza, H. Siti; Rohaya, M. A. W.; Zarina, Z. A. Intan; Hisham, Z. A. Shahrul

2013-11-01

Haematopoietic stem cells (HSCs) are used in the therapy of blood disorders due to the ability of these cells to reconstitute haematopoietic lineage cells when transplanted into myeloablative recipients. However, substantial number of cells is required in order for the reconstitution to take place. Since HSCs present in low frequency, larger number of donor is required to accommodate the demand of transplantable HSCs. Therefore, in vitro expansion of HSCs will have profound impact on clinical purposes. The aim of this study was to expand lineage negative (Lin-) stem cells from human peripheral blood. Total peripheral blood mononuclear cells (PBMNCs) were fractionated from human blood by density gradient centrifugation. Subsequently, PBMNCs were subjected to magnetic assisted cell sorter (MACS) which depletes lineage positive (Lin+) mononuclear cells expressing lineage positive markers such as CD2, CD3, CD11b, CD14, CD15, CD16, CD19, CD56, CD123, and CD235a to obtained Lin- cell population. The ability of Lin+ and Lin- to survive in vitro was explored by culturing both cell populations in complete medium consisting of Alpha-Minimal Essential Medium (AMEM) +10% (v/v) Newborn Calf Serum (NBCS)+ 2% (v/v) pen/strep. In another experiment, Lin+ and Lin- were cultured with complete medium supplemented with 10ng/mL of the following growth factors: stem cell factor (SCF), interleukin (IL)-3, granulocyte-macrophage colony stimulating factor (GM-CSF), 2IU/mL of Erythropoietin (Epo) and 20ng/mL of IL-6. Three samples were monitored in static culture for 22 days. The expansion potential was assessed by the number of total viable cells, counted by trypan blue exclusion assay. It was found that Lin+ mononuclear cells were not able to survive either in normal proliferation medium or proliferation medium supplemented with cytokines. Similarly, Lin- stem cells were not able to survive in proliferation medium however, addition of cytokines into the proliferation medium support Lin- stem cells for at least 18 days. The Lin- stem cells started to response to the cytokines added as early as Day 2 of culture. It is concluded that Lin- stem cells can be expanded in vitro by culturing in proliferation medium supplemented with cytokines.

Nuclear NF-κB Expression Correlates With Outcome Among Patients With Head and Neck Squamous Cell Carcinoma Treated With Primary Chemoradiation Therapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Balermpas, Panagiotis; Michel, Yvonne; Wagenblast, Jens

2013-07-15

Background: To examine whether nuclear NF-κB expression correlates with outcome in patients with head and neck squamous cell carcinoma (HNSCC) treated with primary chemoradiation therapy (CRT). Methods and Materials: Between 2007 and 2010, 101 patients with locally advanced primary HNSCC were treated with definitive simultaneous CRT. Pretreatment biopsy specimens were analyzed for NF-κB p65 (RelA) nuclear immunoreactivity. A sample was assigned to be positive with more than 5% positive nuclear expression. The predictive relevance of NF-κB and clinicopathologic factors for overall survival (OS), progression-free survival (PFS), local progression-free survival (LPFS), and metastasis-free survival (DMFS) was examined by univariate and multivariatemore » analysis. Results: No significant differences between the groups were observed with regard to age, sex, total radiation dose, fractionation mode, total chemotherapy applied, T stage or grading. Patients with p65 nuclear positive biopsy specimens showed significantly a higher rate of lymph node metastasis (cN2c or cN3 status, P=.034). Within a mean follow-up time of 25 months (range, 2.33-62.96 months) OS, PFS, and DMFS were significantly poorer in the p65 nuclear positive group (P=.008, P=.027, and P=.008, respectively). These correlations remained significant in multivariate analysis. Conclusion: NF-κB/p65 nuclear expression is associated with increased lymphatic and hematogenous tumor dissemination and decreased survival in HNSCC patients treated with primary CRT. Our results may foster further investigation of a predictive relevance of NF-κB/p65 and its role as a suitable target for a molecular-based targeted therapy in HNSCC cancer.« less

Survival and Recovery of Methanotrophic Bacteria Starved Under Oxic and Anoxic Conditions

NASA Technical Reports Server (NTRS)

Roslev, Peter; King, Gary M.

1994-01-01

The effects of carbon deprivation on survival of methanotrophic bacteria were compared in cultures incubated in the presence and absence of oxygen in the starvation medium. Survival and recovery of the examined methanotrophs were generally highest for cultures starved under anoxic conditions as indicated by poststarvation measurements of methane oxidation, tetrazolium salt reduction, plate counts, and protein synthesis. Methylosinus trichosporium OB3b survived up to 6 weeks of carbon deprivation under anoxic conditions while maintaining a physiological state that allowed relatively rapid (hours) methane oxidation after substrate addition. A small fraction of cells starved under oxic and anoxic conditions (4 and 10%, respectively) survived more than 10 weeks but required several days for recovery on plates and in liquid medium. A non-spore-forming methanotroph, strain WP 12, displayed 36 to 118% of its initial methane oxidation capacity after 5 days of carbon deprivation. Oxidation rates varied with growth history prior to the experiments as well as with starvation conditions. Strain WP 12 starved under anoxic conditions showed up to 90% higher methane oxidation activity and 46% higher protein production after starvation than did cultures starved under oxic conditions. Only minor changes in biomass and niorpholow were seen for methanotrophic bacteria starved tinder anoxic conditions. In contrast, starvation under oxic conditions resulted in morphology changes and an initial 28 to 35% loss of cell protein. These data suggest that methanotrophic bacteria can survin,e carbon deprivation under anoxic conditions by using maintenance energy derived Solelyr from an anaerobic endogenous metabolism. This capability could partly explain a significant potential for methane oxidation in environments not continuously, supporting aerobic methanotrophic growth.

Long-term results of high-dose conformal radiotherapy for patients with medically inoperable T1-3N0 non-small-cell lung cancer: is low incidence of regional failure due to incidental nodal irradiation?

PubMed

Chen, Ming; Hayman, James A; Ten Haken, Randall K; Tatro, Daniel; Fernando, Shaneli; Kong, Feng-Ming

2006-01-01

To report the results of high-dose conformal irradiation and examine incidental nodal irradiation and nodal failure in patients with inoperable early-stage non-small-cell lung cancer (NSCLC). This analysis included patients with inoperable CT-staged T1-3N0M0 NSCLC treated on our prospective dose-escalation trial. Patients were treated with radiation alone (total dose, 63-102.9 Gy in 2.1-Gy daily fractions) with a three-dimensional conformal technique without intentional nodal irradiation. Bilateral highest mediastinal and upper/lower paratracheal, prevascular and retrotracheal, sub- and para-aortic, subcarinal, paraesophageal, and ipsilateral hilar regions were delineated individually. Nodal failure and doses of incidental irradiation were studied. The potential median follow-up was 104 months. For patients who completed protocol treatment, median survival was 31 months. The actuarial overall survival rate was 86%, 61%, 43%, and 21% and the cause-specific survival rate was 89%, 70%, 53%, and 35% at 1, 2, 3, and 5 years, respectively. Weight loss (p = 0.008) and radiation dose in Gy (p = 0.013) were significantly associated with overall survival. In only 22% and 13% of patients examined did ipsilateral hilar and paratracheal (and subaortic for left-sided tumor) nodal regions receive a dose of > or = 40 Gy, respectively. Less than 10% of all other nodal regions received a dose of > or = 40 Gy. No patients failed initially at nodal sites. Radiation dose is positively associated with overall survival in patients with medically inoperable T1-3N0 NSCLC, though long-term results remain poor. The nodal failure rate is low and does not seem to be due to high-dose incidental irradiation.

Pathological characteristics of spine metastases treated with high-dose single-fraction stereotactic radiosurgery.

PubMed

Katsoulakis, Evangelia; Laufer, Ilya; Bilsky, Mark; Agaram, Narasimhan P; Lovelock, Michael; Yamada, Yoshiya

2017-01-01

OBJECTIVE Spine radiosurgery is increasingly being used to treat spinal metastases. As patients are living longer because of the increasing efficacy of systemic agents, appropriate follow-up and posttreatment management for these patients is critical. Tumor progression after spine radiosurgery is rare; however, vertebral compression fractures are recognized as a more common posttreatment effect. The use of radiographic imaging alone posttreatment may makeit difficult to distinguish tumor progression from postradiation changes such as fibrosis. This is the largest series from a prospective database in which the authors examine histopathology of samples obtained from patients who underwent surgical intervention for presumed tumor progression or mechanical pain secondary to compression fracture. The majority of patients had tumor ablation and resulting fibrosis rather than tumor progression. The aim of this study was to evaluate tumor histopathology and characteristics of patients who underwent pathological sampling because of radiographic tumor progression, fibrosis, or collapsed vertebrae after receiving high-dose single-fraction stereotactic radiosurgery. METHODS Between January 2005 and January 2014, a total of 582 patients were treated with linear accelerator-based single-fraction (18-24 Gy) stereotactic radiosurgery. The authors retrospectively identified 30 patients (5.1%) who underwent surgical intervention for 32 lesions with vertebral cement augmentation for either mechanical pain or instability secondary to vertebral compression fracture (n = 17) or instrumentation (n = 15) for radiographic tumor progression. Radiation and surgical treatment, histopathology, and long-term outcomes were reviewed. Survival and time to recurrence were calculated using the Kaplan-Meier method. RESULTS The mean age at the time of radiosurgery was 59 years (range 36-80 years). The initial pathological diagnoses were obtained for all patients and primarily included radioresistant tumor types, including renal cell carcinoma in 7 (22%), melanoma in 6 (19%), lung carcinoma in 4 (12%), and sarcoma in 3 (9%). The median time to surgical intervention was 24.7 months (range 1.6-50.8 months). The median follow-up and overall survival for all patients were 42.5 months and 41 months (overall survival range 7-86 months), respectively. The majority of assessed lesions showed no evidence of tumor on pathological review (25 of 32, 78%), while a minority of lesions revealed residual tumor (7 of 32, 22%). The median survival for patients after tumor recurrence was 5 months (range 2-70 months). CONCLUSIONS High-dose single-fraction radiosurgery is tumor ablative in the majority of instances. In a minority of cases, tumor persists and salvage treatments should be considered.

Pathological characteristics of spine metastases treated with high-dose single-fraction stereotactic radiosurgery

PubMed Central

Katsoulakis, Evangelia; Laufer, Ilya; Bilsky, Mark; Agaram, Narasimhan P.; Lovelock, Michael; Yamada, Yoshiya

2017-01-01

OBJECTIVE Spine radiosurgery is increasingly being used to treat spinal metastases. As patients are living longer because of the increasing efficacy of systemic agents, appropriate follow-up and posttreatment management for these patients is critical. Tumor progression after spine radiosurgery is rare; however, vertebral compression fractures are recognized as a more common posttreatment effect. The use of radiographic imaging alone posttreatment may make it difficult to distinguish tumor progression from postradiation changes such as fibrosis. This is the largest series from a prospective database in which the authors examine histopathology of samples obtained from patients who underwent surgical intervention for presumed tumor progression or mechanical pain secondary to compression fracture. The majority of patients had tumor ablation and resulting fibrosis rather than tumor progression. The aim of this study was to evaluate tumor histopathology and characteristics of patients who underwent pathological sampling because of radiographic tumor progression, fibrosis, or collapsed vertebrae after receiving high-dose single-fraction stereotactic radiosurgery. METHODS Between January 2005 and January 2014, a total of 582 patients were treated with linear accelerator–based single-fraction (18–24 Gy) stereotactic radiosurgery. The authors retrospectively identified 30 patients (5.1%) who underwent surgical intervention for 32 lesions with vertebral cement augmentation for either mechanical pain or instability secondary to vertebral compression fracture (n = 17) or instrumentation (n = 15) for radiographic tumor progression. Radiation and surgical treatment, histopathology, and long-term outcomes were reviewed. Survival and time to recurrence were calculated using the Kaplan-Meier method. RESULTS The mean age at the time of radiosurgery was 59 years (range 36–80 years). The initial pathological diagnoses were obtained for all patients and primarily included radioresistant tumor types, including renal cell carcinoma in 7 (22%), melanoma in 6 (19%), lung carcinoma in 4 (12%), and sarcoma in 3 (9%). The median time to surgical intervention was 24.7 months (range 1.6–50.8 months). The median follow-up and overall survival for all patients were 42.5 months and 41 months (overall survival range 7–86 months), respectively. The majority of assessed lesions showed no evidence of tumor on pathological review (25 of 32, 78%), while a minority of lesions revealed residual tumor (7 of 32, 22%). The median survival for patients after tumor recurrence was 5 months (range 2–70 months). CONCLUSIONS High-dose single-fraction radiosurgery is tumor ablative in the majority of instances. In a minority of cases, tumor persists and salvage treatments should be considered. PMID:28041326

Use of an image-guided robotic radiosurgery system for the treatment of canine nonlymphomatous nasal tumors.

PubMed

Glasser, Seth A; Charney, Sarah; Dervisis, Nikolaos G; Witten, Matthew R; Ettinger, Susan; Berg, Jason; Joseph, Richard

2014-01-01

An image-guided robotic stereotactic radiosurgery (SRS) system can be used to deliver curative-intent radiation in either single fraction or hypofractionated doses. Medical records for 19 dogs with nonlymphomatous nasal tumors treated with hypofractionated image-guided robotic stereotactic body radiotherapy (SBRT), either with or without adjunctive treatment, were retrospectively analyzed for survival and prognostic factors. Median survival time (MST) was evaluated using Kaplan-Meier survival curves. Age, breed, tumor type, stage, tumor size, prescribed radiation dose, and heterogeneity index were analyzed for prognostic significance. Dogs were treated with three consecutive-day, 8-12 gray (Gy) fractions of image-guided robotic SBRT. Overall MST was 399 days. No significant prognostic factors were identified. Acute side effects were rare and mild. Late side effects included one dog with an oronasal fistula and six dogs with seizures. In three of six dogs, seizures were a presenting complaint prior to SBRT. The cause of seizures in the remaining three dogs could not be definitively determined due to lack of follow-up computed tomography (CT) imaging. The seizures could have been related to either progression of disease or late radiation effect. Results indicate that image-guided robotic SBRT, either with or without adjunctive therapy, for canine nonlymphomatous nasal tumors provides comparable survival times (STs) to daily fractionated megavoltage radiation with fewer required fractions and fewer acute side effects.

Clinical Outcomes and Prognostic Factors of High-Dose Proton Beam Therapy for Peripheral Stage I Non-Small-Cell Lung Cancer.

PubMed

Hatayama, Yoshiomi; Nakamura, Tatsuya; Suzuki, Motohisa; Azami, Yusuke; Ono, Takashi; Yabuuchi, Tomonori; Hayashi, Yuichiro; Kimura, Kanako; Hirose, Katsumi; Wada, Hitoshi; Hareyama, Masato; Kikuchi, Yasuhiro; Takai, Yoshihiro

2016-09-01

The efficacy, toxicity, and prognostic factors of high-dose proton beam therapy (PBT) for peripheral stage I non-small-cell lung cancer were assessed in this retrospective study. Fifty patients with peripheral stage I non-small-cell lung cancer, two of whom had heterochronic multiple lung cancers, underwent high-dose PBT between January 2009 and September 2014. The relative biological effectiveness of the proton beam was defined as 1.1. The beam energy and spread-out Bragg peak were fine-tuned for the 90% isodose volume of the prescribed dosage to encompass the planning target volume. The cumulative survival curves were calculated using the Kaplan-Meier method. Treatment toxicities were evaluated using version 4 of the Common Terminology Criteria for Adverse Events, version 4. The study included 35 males and 15 females with a median age of 72.5 years. The median follow-up period was 22.8 months. The clinical stage was IA in 44 (85%) and IB in eight (15%) tumors. The total dose of PBT was 66 GyE in 10 fractions in all tumors. Three-year overall survival rate among all patients was 87.9% (95% confidence interval [CI], 94.8%-73.2%). Forty-five patients were alive, and 5 were dead. Three-year local control and progression-free survival rates were 95.7% (95% CI, 98.9%-83.8%) and 76.3% (95% CI, 86.9%-59.3%), respectively. Only one patient experienced Grade 2 pneumonitis. High-dose PBT may be an effective and safe treatment option for patients with stage I non-small-cell lung cancer. Copyright © 2015 Elsevier Inc. All rights reserved.

Universal behavior of the osmotically compressed cell and its analogy to the colloidal glass transition

PubMed Central

Zhou, E. H.; Trepat, X.; Park, C. Y.; Lenormand, G.; Oliver, M. N.; Mijailovich, S. M.; Hardin, C.; Weitz, D. A.; Butler, J. P.; Fredberg, J. J.

2009-01-01

Mechanical robustness of the cell under different modes of stress and deformation is essential to its survival and function. Under tension, mechanical rigidity is provided by the cytoskeletal network; with increasing stress, this network stiffens, providing increased resistance to deformation. However, a cell must also resist compression, which will inevitably occur whenever cell volume is decreased during such biologically important processes as anhydrobiosis and apoptosis. Under compression, individual filaments can buckle, thereby reducing the stiffness and weakening the cytoskeletal network. However, the intracellular space is crowded with macromolecules and organelles that can resist compression. A simple picture describing their behavior is that of colloidal particles; colloids exhibit a sharp increase in viscosity with increasing volume fraction, ultimately undergoing a glass transition and becoming a solid. We investigate the consequences of these 2 competing effects and show that as a cell is compressed by hyperosmotic stress it becomes progressively more rigid. Although this stiffening behavior depends somewhat on cell type, starting conditions, molecular motors, and cytoskeletal contributions, its dependence on solid volume fraction is exponential in every instance. This universal behavior suggests that compression-induced weakening of the network is overwhelmed by crowding-induced stiffening of the cytoplasm. We also show that compression dramatically slows intracellular relaxation processes. The increase in stiffness, combined with the slowing of relaxation processes, is reminiscent of a glass transition of colloidal suspensions, but only when comprised of deformable particles. Our work provides a means to probe the physical nature of the cytoplasm under compression, and leads to results that are universal across cell type. PMID:19520830

Comparison of the X-radiation, drug and ultraviolet-radiation responses of clones isolated from a human colorectal tumor cell line.

PubMed

Qutob, Sami S; Multani, Asha S; Pathak, S; Feng, Y; Kendal, Wayne S; Ng, Cheng E

2004-03-01

We isolated several clones with a wide range of responses to X radiation from an unirradiated human colorectal (HCT 116) tumor cell line. The responses of one of these clones (HCT116-Clone10) and nine other clones to either fractionated or acute (i.e. single, nonfractionated doses) X irradiation in vitro was similar to that of the parental cell line. By contrast, after the same types of treatment, another clone (HCT116-Clone2) manifested a significantly increased survival whereas a third clone (HCT116-CloneK) manifested a significantly decreased survival relative to the parental cell line. This suggested that they were, respectively, a radioresistant and a radiosensitive clone. All three clones (clones 2, 10, K) retained their tumorigenic phenotype and formed tumors in nude mice. G-banding studies demonstrated that they were of human origin and were derived from the same parental cell line. The metaphases of HCT116-Clone2 demonstrated features commonly associated with genomic instability (i.e. mitotic catastrophe including chromosome and chromatid breaks, dicentrics and additional nonclonal markers). Data obtained by quantitative fluorescence in situ hybridization (Q- FISH) analysis failed to demonstrate any apparent correlation between the radiosensitivity and the relative telomere content of these three clones. Interestingly, HCT116-CloneK was the most resistant to several chemotherapeutic drugs (topotecan, camptothecin, etoposide and cisplatin) with diverse mechanisms of action. Also, there were no significant differences in the survivals of the three clones after treatment with UV radiation. Because of the lack of overlap among the relative sensitivities of these clones to X radiation, chemotherapeutic drugs and UV radiation, these clones may be useful models for evaluating the genetic basis of the response of human tumor cells to these treatment agents both in vitro and in vivo.

Evaluation of 2 whole-brain radiotherapy schedules and prognostic factors for brain metastases in breast cancer patients.

PubMed

Rades, Dirk; Lohynska, Radka; Veninga, Theo; Stalpers, Lukas J A; Schild, Steven E

2007-12-01

The majority of breast cancer patients with brain metastases receive whole-brain radiotherapy (WBRT) and have a survival of only a few months. A short WBRT regimen would be preferable if it provides survival that is similar to that achieved with longer programs. This retrospective study compared survival and local control within the brain resulting from short-course WBRT with longer programs in 207 breast cancer patients. Sixty-nine patients treated with 5 fractions of 4 grays (Gy) each given within 5 days were compared with 138 patients treated with 10 fractions of 3 Gy each given over 2 weeks or 20 fractions of 2 Gy each given over 4 weeks. Six additional potential prognostic factors were investigated: age, Karnofsky performance score (KPS), number of brain metastases, the presence of extracranial metastases, interval from tumor diagnosis to WBRT, and recursive partitioning analysis (RPA) class. On univariate analysis, the WBRT regimen was not found to be associated with survival (P=.254) or local control (P=.397). Improved survival was associated with a KPS>70 (P<.001), single brain metastasis (P=.023), the absence of extracranial metastases (P<.001), and lower RPA class (P<.001). On multivariate analysis, which was performed without RPA class because this is a confounding variable, KPS (relative risk [RR] of 4.00; P<.001) and the presence of extracranial metastases (RR of 1.54; P=.024) maintained statistical significance. On univariate analysis, local control was associated with KPS (P<.001) and RPA class (P<.001). On multivariate analysis, local control was found to be associated with a KPS>70 (RR of 5.75; P<.001). Short-course WBRT with 5 fractions of 4 Gy each resulted in survival and local control that were similar to longer programs in breast cancer patients with brain metastases. The dose of 5 fractions of 4 Gy each appears preferable for the majority of these patients because it is less time consuming and more convenient. Copyright (c) 2007 American Cancer Society.

Modeling the relationship between fluorodeoxyglucose uptake and tumor radioresistance as a function of the tumor microenvironment.

PubMed

Jeong, Jeho; Deasy, Joseph O

2014-01-01

High fluorodeoxyglucose positron emission tomography (FDG-PET) uptake in tumors has often been correlated with increasing local failure and shorter overall survival, but the radiobiological mechanisms of this uptake are unclear. We explore the relationship between FDG-PET uptake and tumor radioresistance using a mechanistic model that considers cellular status as a function of microenvironmental conditions, including proliferating cells with access to oxygen and glucose, metabolically active cells with access to glucose but not oxygen, and severely hypoxic cells that are starving. However, it is unclear what the precise uptake levels of glucose should be for cells that receive oxygen and glucose versus cells that only receive glucose. Different potential FDG uptake profiles, as a function of the microenvironment, were simulated. Predicted tumor doses for 50% control (TD50) in 2 Gy fractions were estimated for each assumed uptake profile and for various possible cell mixtures. The results support the hypothesis of an increased avidity of FDG for cells in the intermediate stress state (those receiving glucose but not oxygen) compared to well-oxygenated (and proliferating) cells.

Acid ceramidase in prostate cancer radiation therapy resistance and relapse

NASA Astrophysics Data System (ADS)

Cheng, Joseph C.

Prostate tumor cell escape from ionizing radiation (IR)-induced killing can lead to disease progression and relapse. Sphingolipids such as ceramide and sphingosine 1-phosphate influence signal transduction pathways that regulate stress response in cancer cells. In particular, metabolism of apoptotic ceramide constitutes an important survival adaptation. Assessments of enzyme activity, mRNA, and protein demonstrated preferential upregulation of the ceramide deacylating enzyme acid ceramidase (AC) in irradiated cancer cells. Promoter-reporter and ChIP-qPCR assays revealed AC transcription by activator protein 1 (AP-1) is sensitive to pharmacological inhibition of de novo ceramide biosynthesis, identifying a protective feedback mechanism that mitigates the effects of IR-induced ceramide. Deregulation of c-Jun, in particular, induced marked radiosensitization in vitro and in vivo, which was rescued by ectopic AC over-expression. AC over-expression in prostate cancer clonogens surviving 80 Gray fractionated irradiation was associated with increased radioresistance and proliferation, suggesting a role in radiotherapy failure and relapse. Indeed, immunohistochemical analysis of human prostate cancer tissues revealed higher levels of AC after radiotherapy failure than therapy-naive adenocarcinoma, PIN, or benign tissues. By genetically downregulating AC with small interfering RNA (siRNA), we observed radiosensitization of cells using clonogenic and cytotoxicity assays. Finally, treatment with lysosomotropic small molecule inhibitors of AC, LCL385 or LCL521, induced prostate cancer xenograft radiosensitization and long-term suppression, suggesting AC is a tractable target for adjuvant radiotherapy.

Management of patients with multiple myeloma: emphasizing the role of high-dose therapy.

PubMed

Kyle, R A

2001-06-01

Treatment for multiple myeloma should not be given until the patient is symptomatic or at risk for the occurrence of complications of the disease. If the patient is younger than 70 years, the physician should seriously consider an autologous peripheral blood stem cell transplant. Most physicians initially administer vincristine/doxorubicin/dexamethasone (VAD) for 3 to 4 months and then collect the stem cells before exposure to alkylating agents. Following stem cell collection, one may proceed with high-dose chemotherapy and then infusion of the stem cells, or one can administer alkylating agents until a plateau is reached and delay transplantation until progressive disease occurs. There is no difference in overall survival between early and late transplantation, but the former avoids the cost and inconvenience of alkylating agent therapy. Double or tandem autologous stem cell transplants may produce better results, but the evidence is not strong. Almost all patients have a relapse after an autologous stem cell transplant, so efforts are being made to prolong the response with a2-interferon or dendritic cell therapy. Allogeneic bone marrow transplantation is feasible for only 5%-10% of patients, but the mortality is high and it is curative in only a small fraction of patients. Treatment with melphalan and prednisone results in an objective response in 50%-60% of patients. Combinations of alkylating agents produce a higher response rate, but there is no survival benefit. Thalidomide produces an objective response in about one third of patients with refractory disease. It currently is being studied in conjunction with dexamethasone for conventional initial therapy.

Palmatine inhibits growth and invasion in prostate cancer cell: Potential role for rpS6/NFκB/FLIP.

PubMed

Hambright, Heather G; Batth, Izhar Singh; Xie, Jianping; Ghosh, Rita; Kumar, Addanki Pratap

2015-10-01

Novel agents are desperately needed for improving the quality of life and 5-year survival to more than 30% for metastatic castrate-resistant prostate cancer. Previously we showed that Nexrutine, Phellodendron amurense bark extract, inhibits prostate tumor growth in vitro and in vivo. Subsequently using biochemical fractionation we identified butanol fraction contributes to the observed biological activities. We report here that palmatine, which is present in the butanol fraction, selectively inhibits growth of prostate cancer cells without significant effect on non-tumorigenic prostate epithelial cells. By screening receptor tyrosine kinases in a protein kinase array, we identified ribosomal protein S6, a downstream target of p70S6K and the Akt/mTOR signaling cascade as a potential target. We further show that palmatine treatment is associated with decreased activation of NFκB and its downstream target gene FLIP. These events led to inhibition of invasion. Similar results were obtained using parent extract Nexrutine (Nx) suggesting that palmatine either in the purified form or as one of the components in Nx is a potent cytotoxic agent with tumor invasion inhibitory properties. Synergistic inhibition of rpS6/NFκB/FLIP axis with palmatine may have therapeutic potential for the treatment of prostate cancer and possibly other malignancies with their constitutive activation. These data support a biological link between rpS6/NFκB/FLIP in mediating palmatine-induced inhibitory effects and warrants additional preclinical studies to test its therapeutic efficacy. © 2014 Wiley Periodicals, Inc.

Piper betle extracts exhibit antitumor activity by augmenting antioxidant potential

PubMed Central

ALAM, BADRUL; MAJUMDER, RAJIB; AKTER, SHAHINA; LEE, SANG-HAN

2015-01-01

The present study was conducted to evaluate the methanolic extract of Piper betle leaves (MPBL) and its organic fractions with regard to antitumor activity against Ehrlich ascites carcinoma (EAC) in Swiss albino mice and to confirm their antioxidant activities. At 24 h post-intraperitoneal inoculation of tumor cells into mice, extracts were administered at 25, 50 and 100 mg/kg body weight for nine consecutive days. The antitumor effects of the extracts were then assessed according to tumor volume, packed cell count, viable and non-viable tumor cell count, median survival time and increase in life span of EAC-bearing mice. Next, hematological profiles and serum biochemical parameters were calculated, and antioxidant properties were assessed by estimating lipid peroxidation, reduced glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT) levels. MPBL and the ethylacetate fraction (EPBL) at a dose of 100 mg/kg induced a significant decrease in tumor volume, packed cell volume and viable cell count and increased the life span of the EAC-bearing mice (P<0.05). Hematological and serum biochemical profiles were restored to normal levels in the extract-treated mice compared with the EAC control mice. MPBL and EPBL treatment significantly decreased lipid peroxidation (P<0.05) and restored GSH, SOD and CAT levels towards normal compared with the EAC control. Taken together, the results of the present study demonstrated that Piper betle extracts exhibit significant antitumor activity, which may be attributed to the augmentation of endogenous antioxidant potential. PMID:25624910

Piper betle extracts exhibit antitumor activity by augmenting antioxidant potential.

PubMed

Alam, Badrul; Majumder, Rajib; Akter, Shahina; Lee, Sang-Han

2015-02-01

The present study was conducted to evaluate the methanolic extract of Piper betle leaves (MPBL) and its organic fractions with regard to antitumor activity against Ehrlich ascites carcinoma (EAC) in Swiss albino mice and to confirm their antioxidant activities. At 24 h post-intraperitoneal inoculation of tumor cells into mice, extracts were administered at 25, 50 and 100 mg/kg body weight for nine consecutive days. The antitumor effects of the extracts were then assessed according to tumor volume, packed cell count, viable and non-viable tumor cell count, median survival time and increase in life span of EAC-bearing mice. Next, hematological profiles and serum biochemical parameters were calculated, and antioxidant properties were assessed by estimating lipid peroxidation, reduced glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT) levels. MPBL and the ethylacetate fraction (EPBL) at a dose of 100 mg/kg induced a significant decrease in tumor volume, packed cell volume and viable cell count and increased the life span of the EAC-bearing mice (P<0.05). Hematological and serum biochemical profiles were restored to normal levels in the extract-treated mice compared with the EAC control mice. MPBL and EPBL treatment significantly decreased lipid peroxidation (P<0.05) and restored GSH, SOD and CAT levels towards normal compared with the EAC control. Taken together, the results of the present study demonstrated that Piper betle extracts exhibit significant antitumor activity, which may be attributed to the augmentation of endogenous antioxidant potential.

Antitumor effect of culinary-medicinal oyster mushroom, Pleurotus ostreatus (Jacq.: Fr.) P. Kumm., derived protein fraction on tumor-bearing mice models.

PubMed

Maiti, Swatilekha; Mallick, Sanjaya Kumar; Bhutia, Sujit Kumar; Behera, Birendra; Mandal, Mohitosh; Maiti, Tapas K

2011-01-01

Previously, we reported the in vitro anticancer and immunomodulatory effect of a protein fraction designated as Cibacron blue affinity purified protein (CBAEP) obtained from the culinary-medicinal oyster mushroom, Pleurotus ostreatus. In the present study, we investigated the in vivo antitumor potential of CBAEP in different tumor-bearing mice models and studied the detailed mechanism of tumor regression in Dalton lymphoma (DL)-bearing mice. The lethal dose (LD50) of CBAEP was found to be 55 mg/kg body weight and sublethal doses (5 mg/kg and 10 mg/kg body weight) showed a prolonged tumor survival time in DL, Sarcoma-180, and B16F0 melanoma tumor-bearing mice. Further, CBAEP reduced about 35.68 and 51.43% DL cell growth in 5 and 10 mg/kg body weight, respectively. The in vivo CBAEP treatment showed an apoptotic feature as demonstrated in morphological study and sub-G0/G1 population in cell cycle and Western blot of DL cells. CBAEP also activated immunosuppression condition in DL tumor-bearing host. It also stimulated immune cells in the presence of nonspecific immunostunulator (LPS and ConA) ex vivo as well as enhanced Th1 response with production of TNF-α, IFN-γ, and IL-2. Moreover, it activated tumor-associated macrophages and NK cells. The present findings revealed the potent antitumor property of CBAEP, which might help in developing a new anticancer drug.

Towards an integrative computational model for simulating tumor growth and response to radiation therapy

NASA Astrophysics Data System (ADS)

Marrero, Carlos Sosa; Aubert, Vivien; Ciferri, Nicolas; Hernández, Alfredo; de Crevoisier, Renaud; Acosta, Oscar

2017-11-01

Understanding the response to irradiation in cancer radiotherapy (RT) may help devising new strategies with improved tumor local control. Computational models may allow to unravel the underlying radiosensitive mechanisms intervening in the dose-response relationship. By using extensive simulations a wide range of parameters may be evaluated providing insights on tumor response thus generating useful data to plan modified treatments. We propose in this paper a computational model of tumor growth and radiation response which allows to simulate a whole RT protocol. Proliferation of tumor cells, cell life-cycle, oxygen diffusion, radiosensitivity, RT response and resorption of killed cells were implemented in a multiscale framework. The model was developed in C++, using the Multi-formalism Modeling and Simulation Library (M2SL). Radiosensitivity parameters extracted from literature enabled us to simulate in a regular grid (voxel-wise) a prostate cell tissue. Histopathological specimens with different aggressiveness levels extracted from patients after prostatectomy were used to initialize in silico simulations. Results on tumor growth exhibit a good agreement with data from in vitro studies. Moreover, standard fractionation of 2 Gy/fraction, with a total dose of 80 Gy as a real RT treatment was applied with varying radiosensitivity and oxygen diffusion parameters. As expected, the high influence of these parameters was observed by measuring the percentage of survival tumor cell after RT. This work paves the way to further models allowing to simulate increased doses in modified hypofractionated schemes and to develop new patient-specific combined therapies.

At the Crossroads of Cancer Stem Cells, Radiation Biology, and Radiation Oncology.

PubMed

Gerweck, Leo E; Wakimoto, Hiroaki

2016-03-01

Reports that a small subset of tumor cells initiate and sustain tumor growth, are resistant to radiation and drugs, and bear specific markers have led to an explosion of cancer stem cell research. These reports imply that the evaluation of therapeutic response by changes in tumor volume is misleading, as volume changes reflect the response of the sensitive rather than the resistant tumorigenic cell population. The reports further suggest that the marker-based selection of the tumor cell population will facilitate the development of radiation treatment schedules, sensitizers, and drugs that specifically target the resistant tumorigenic cells that give rise to treatment failure. This review presents evidence that contests the observations that cancer stem cell markers reliably identify the subset of tumor cells that sustain tumor growth and that the marker-identified population is radioresistant relative to the marker-negative cells. Experimental studies show that cells and tumors that survive large radiation doses are not more radioresistant than unirradiated cells and tumors, and also show that the intrinsic radiosensitivity of unsorted colony-forming tumor cells, in combination with the fraction of unsorted tumor cells that are tumor initiating, predicts tumor radiocurability. ©2016 American Association for Cancer Research.

Survival probability of diffusion with trapping in cellular neurobiology

NASA Astrophysics Data System (ADS)

Holcman, David; Marchewka, Avi; Schuss, Zeev

2005-09-01

The problem of diffusion with absorption and trapping sites arises in the theory of molecular signaling inside and on the membranes of biological cells. In particular, this problem arises in the case of spine-dendrite communication, where the number of calcium ions, modeled as random particles, is regulated across the spine microstructure by pumps, which play the role of killing sites, while the end of the dendritic shaft is an absorbing boundary. We develop a general mathematical framework for diffusion in the presence of absorption and killing sites and apply it to the computation of the time-dependent survival probability of ions. We also compute the ratio of the number of absorbed particles at a specific location to the number of killed particles. We show that the ratio depends on the distribution of killing sites. The biological consequence is that the position of the pumps regulates the fraction of calcium ions that reach the dendrite.

An inadvertent capture cell for orbital debris and micrometeorites - The main electronics box thermal blanket of the solar maximum satellite

NASA Technical Reports Server (NTRS)

Rietmeijer, F. J. M.; Schramm, L. S.; Barrett, R. A.; Mckay, D. S.; Zook, H. A.

1986-01-01

The physical properties of impact features in the Solar Max main electronics box thermal blanket are consistent with hypervelocity impacts of particles in the near-earth space environment. The majority of particles are orbital debris and include spacecraft paints and bismuth-rich particles. At least 30 percent of all impact features are caused by micrometeorites, which include silicates and sulfides. Some micrometeorites survive impact with only minor shock-metamorphic effects or chemical fractionation. Currently calibration experiments are under way to relate flux to particle diameter (or mass).

A Gammaherpesvirus Bcl-2 Ortholog Blocks B Cell Receptor-Mediated Apoptosis and Promotes the Survival of Developing B Cells In Vivo

PubMed Central

Coleman, Carrie B.; McGraw, Jennifer E.; Feldman, Emily R.; Roth, Alexa N.; Keyes, Lisa R.; Grau, Katrina R.; Cochran, Stephanie L.; Waldschmidt, Thomas J.; Liang, Chengyu; Forrest, J. Craig; Tibbetts, Scott A.

2014-01-01

Gammaherpesviruses such as Epstein-Barr virus (EBV) and Kaposi's sarcoma-associated herpesvirus (KSHV, HHV-8) establish lifelong latency in their hosts and are associated with the development of several types of malignancies, including a subset of B cell lymphomas. These viruses are thought to co-opt the process of B cell differentiation to latently infect a fraction of circulating memory B cells, resulting in the establishment of a stable latency setpoint. However, little is known about how this infected memory B cell compartment is maintained throughout the life of the host. We have previously demonstrated that immature and transitional B cells are long-term latency reservoirs for murine gammaherpesvirus 68 (MHV68), suggesting that infection of developing B cells contributes to the maintenance of lifelong latency. During hematopoiesis, immature and transitional B cells are subject to B cell receptor (BCR)-mediated negative selection, which results in the clonal deletion of autoreactive B cells. Interestingly, numerous gammaherpesviruses encode homologs of the anti-apoptotic protein Bcl-2, suggesting that virus inhibition of apoptosis could subvert clonal deletion. To test this, we quantified latency establishment in mice inoculated with MHV68 vBcl-2 mutants. vBcl-2 mutant viruses displayed a marked decrease in the frequency of immature and transitional B cells harboring viral genome, but this attenuation could be rescued by increased host Bcl-2 expression. Conversely, vBcl-2 mutant virus latency in early B cells and mature B cells, which are not targets of negative selection, was remarkably similar to wild-type virus. Finally, in vivo depletion of developing B cells during chronic infection resulted in decreased mature B cell latency, demonstrating a key role for developing B cells in the maintenance of lifelong latency. Collectively, these findings support a model in which gammaherpesvirus latency in circulating mature B cells is sustained in part through the recurrent infection and vBcl-2-mediated survival of developing B cells. PMID:24516386

Cell wall-anchored nuclease of Streptococcus sanguinis contributes to escape from neutrophil extracellular trap-mediated bacteriocidal activity.

PubMed

Morita, Chisato; Sumioka, Ryuichi; Nakata, Masanobu; Okahashi, Nobuo; Wada, Satoshi; Yamashiro, Takashi; Hayashi, Mikako; Hamada, Shigeyuki; Sumitomo, Tomoko; Kawabata, Shigetada

2014-01-01

Streptococcus sanguinis, a member of the commensal mitis group of streptococci, is a primary colonizer of the tooth surface, and has been implicated in infectious complications including bacteremia and infective endocarditis. During disease progression, S. sanguinis may utilize various cell surface molecules to evade the host immune system to survive in blood. In the present study, we discovered a novel cell surface nuclease with a cell-wall anchor domain, termed SWAN (streptococcal wall-anchored nuclease), and investigated its contribution to bacterial resistance against the bacteriocidal activity of neutrophil extracellular traps (NETs). Recombinant SWAN protein (rSWAN) digested multiple forms of DNA including NET DNA and human RNA, which required both Mg(2+) and Ca(2+) for optimum activity. Furthermore, DNase activity of S. sanguinis was detected around growing colonies on agar plates containing DNA. In-frame deletion of the swan gene mostly reduced that activity. These findings indicated that SWAN is a major nuclease displayed on the surface, which was further confirmed by immuno-detection of SWAN in the cell wall fraction. The sensitivity of S. sanguinis to NET killing was reduced by swan gene deletion. Moreover, heterologous expression of the swan gene rendered a Lactococcus lactis strain more resistant to NET killing. Our results suggest that the SWAN nuclease on the bacterial surface contributes to survival in the potential situation of S. sanguinis encountering NETs during the course of disease progression.

Cell Wall-Anchored Nuclease of Streptococcus sanguinis Contributes to Escape from Neutrophil Extracellular Trap-Mediated Bacteriocidal Activity

PubMed Central

Nakata, Masanobu; Okahashi, Nobuo; Wada, Satoshi; Yamashiro, Takashi; Hayashi, Mikako; Hamada, Shigeyuki; Sumitomo, Tomoko; Kawabata, Shigetada

2014-01-01

Streptococcus sanguinis, a member of the commensal mitis group of streptococci, is a primary colonizer of the tooth surface, and has been implicated in infectious complications including bacteremia and infective endocarditis. During disease progression, S. sanguinis may utilize various cell surface molecules to evade the host immune system to survive in blood. In the present study, we discovered a novel cell surface nuclease with a cell-wall anchor domain, termed SWAN (streptococcal wall-anchored nuclease), and investigated its contribution to bacterial resistance against the bacteriocidal activity of neutrophil extracellular traps (NETs). Recombinant SWAN protein (rSWAN) digested multiple forms of DNA including NET DNA and human RNA, which required both Mg2+ and Ca2+ for optimum activity. Furthermore, DNase activity of S. sanguinis was detected around growing colonies on agar plates containing DNA. In-frame deletion of the swan gene mostly reduced that activity. These findings indicated that SWAN is a major nuclease displayed on the surface, which was further confirmed by immuno-detection of SWAN in the cell wall fraction. The sensitivity of S. sanguinis to NET killing was reduced by swan gene deletion. Moreover, heterologous expression of the swan gene rendered a Lactococcus lactis strain more resistant to NET killing. Our results suggest that the SWAN nuclease on the bacterial surface contributes to survival in the potential situation of S. sanguinis encountering NETs during the course of disease progression. PMID:25084357

Repeated oral dosing of TAS-102 confers high trifluridine incorporation into DNA and sustained antitumor activity in mouse models

PubMed Central

TANAKA, NOZOMU; SAKAMOTO, KAZUKI; OKABE, HIROYUKI; FUJIOKA, AKIO; YAMAMURA, KEISUKE; NAKAGAWA, FUMIO; NAGASE, HIDEKI; YOKOGAWA, TATSUSHI; OGUCHI, KEI; ISHIDA, KEIJI; OSADA, AKIKO; KAZUNO, HIROMI; YAMADA, YUKARI; MATSUO, KENICHI

2014-01-01

TAS-102 is a novel oral nucleoside antitumor agent containing trifluridine (FTD) and tipiracil hydrochloride (TPI). The compound improves overall survival of colorectal cancer (CRC) patients who are insensitive to standard chemotherapies. FTD possesses direct antitumor activity since it inhibits thymidylate synthase (TS) and is itself incorporated into DNA. However, the precise mechanisms underlying the incorporation into DNA and the inhibition of TS remain unclear. We found that FTD-dependent inhibition of TS was similar to that elicited by fluorodeoxyuridine (FdUrd), another clinically used nucleoside analog. However, washout experiments revealed that FTD-dependent inhibition of TS declined rapidly, whereas FdUrd activity persisted. The incorporation of FTD into DNA was significantly higher than that of other antitumor nucleosides. Additionally, orally administered FTD had increased antitumor activity and was incorporated into DNA more effectively than continuously infused FTD. When TAS-102 was administered, FTD gradually accumulated in tumor cell DNA, in a TPI-independent manner, and significantly delayed tumor growth and prolonged survival, compared to treatment with 5-FU derivatives. TAS-102 reduced the Ki-67-positive cell fraction, and swollen nuclei were observed in treated tumor tissue. The amount of FTD incorporation in DNA and the antitumor activity of TAS-102 in xenograft models were positively and significantly correlated. These results suggest that TAS-102 exerts its antitumor activity predominantly due to its DNA incorporation, rather than as a result of TS inhibition. The persistence of FTD in the DNA of tumor cells treated with TAS-102 may underlie its ability to prolong survival in cancer patients. PMID:25230742

Feasibility and efficacy of helical intensity-modulated radiotherapy for stage III non-small cell lung cancer in comparison with conventionally fractionated 3D-CRT.

PubMed

He, Jian; Huang, Yan; Chen, Yixing; Shi, Shiming; Ye, Luxi; Hu, Yong; Zhang, Jianying; Zeng, Zhaochong

2016-05-01

The standard treatment for stage III non-small-cell lung cancer (NSCLC) is still 60 Gy in conventional fractions combined with concurrent chemotherapy; however, the resulting local controls are disappointing. The aim of this study was to compare and assess the feasibility and efficacy of hypofractionated chemoradiotherapy using helical tomotherapy (HT) with conventional fractionation as opposed to using three-dimensional conformal radiotherapy (3D-CRT) for stage III NSCLC. Sixty-nine patients with stage III (AJCC 7th edition) NSCLC who underwent definitive radiation treatment at our institution between July 2011 and November 2013 were reviewed and analyzed retrospectively. A dose of 60 Gy in 20 fractions was delivered in the HT group (n=34), whereas 60 Gy in 30 fractions in the 3D-CRT group (n=35). Primary endpoints were toxicity, overall response rate, overall survival (OS) and progression-free survival (PFS). The median follow-up period was 26.4 months. V20 (P=0.005), V30 (P=0.001), V40 (P=0.004), mean lung dose (P=0.000) and max dose of spinal cord (P=0.005) were significantly lower in the HT group than in the 3D-CRT group. There was no significant difference in the incidences of acute radiation pneumonitis (RP) ≥ grade 2 between the two groups, whereas the incidences of acute radiation esophagitis ≥ grade 2 were significantly lower in the HT group than in the 3D-CRT group (P=0.027). Two-year overall response rate was significantly higher in the HT group than in the 3D-CRT group (P=0.015). One- and 2-year OS rates were significantly higher in the HT group (95.0% and 68.7%, respectively) than in the 3D-CRT group (85.5% and 47.6%, respectively; P=0.0236). One- and 2-year PFS rates were significantly higher in the HT group (57.8% and 26.3%, respectively) than in the 3D-CRT group (32.7% and 11.4%, respectively; P=0.0351). Univariate analysis indicated that performance status (PS), T stage and radiotherapy technique were significant prognostic factors for both OS and PFS. Multivariate analysis indicated that PS and radiotherapy technique were independent prognostic factors of OS and PS was independent prognostic factor of PFS. Hypofractionated chemoradiotherapy via HT can shorten the radiotherapy time without increasing treatment-related toxicity. The preliminary findings are that OS and PFS can be improved by hypofractionated chemoradiotherapy via HT for patients with stage III NSCLC.

Influence of p53 status on the effects of boron neutron capture therapy in glioblastoma.

PubMed

Seki, Keiko; Kinashi, Yuko; Takahashi, Sentaro

2015-01-01

The tumor suppressor gene p53 is mutated in glioblastoma. We studied the relationship between the p53 gene and the biological effects of boron neutron capture therapy (BNCT). The human glioblastoma cells; A172, expressing wild-type p53, and T98G, with mutant p53, were irradiated by the Kyoto University Research Reactor (KUR). The biological effects after neutron irradiation were evaluated by the cell killing effect, 53BP1 foci assay and apoptosis induction. The survival-fraction data revealed that A172 was more radiosensitive than T98G, but the difference was reduced when boronophenylalanine (BPA) was present. Both cell lines exhibited similar numbers of foci, suggesting that the initial levels of DNA damage did not depend on p53 function. Detection of apoptosis revealed a lower rate of apoptosis in the T98G. BNCT causes cell death in glioblastoma cells, regardless of p53 mutation status. In T98G cells, cell killing and apoptosis occurred effectively following BNCT. Copyright© 2015 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

Prognostic and Added Value of Two-Dimensional Global Longitudinal Strain for Prediction of Survival in Patients with Light Chain Amyloidosis Undergoing Autologous Hematopoietic Cell Transplantation.

PubMed

Pun, Shawn C; Landau, Heather J; Riedel, Elyn R; Jordan, Jonathan; Yu, Anthony F; Hassoun, Hani; Chen, Carol L; Steingart, Richard M; Liu, Jennifer E

2018-01-01

Autologous hematopoietic cell transplantation (HCT) is a first-line therapy for prolonging survival in patients with light-chain (AL) amyloidosis. Cardiac involvement is the most important determinant of survival. However, patients with advanced cardiac involvement have often been excluded from HCT because of high risk for transplantation-related mortality and poor overall survival. Whether baseline left ventricular global longitudinal strain (GLS) can provide additional risk stratification and predict survival after HCT in this high-risk population remains unclear. The aim of this study was to evaluate the prognostic implication of baseline GLS and the added value of GLS beyond circulating cardiac biomarkers for risk stratification in patients with AL amyloidosis undergoing HCT. Eighty-two patients with newly diagnosed AL amyloidosis who underwent upfront HCT between January 2007 and April 2014 were included in the study. Clinical, echocardiographic, and serum cardiac biomarker data were collected at baseline and 12 months following HCT. GLS measurements were performed using a vendor-independent offline system. The median follow-up time for survivors was 58 months. Sixty-four percent of patients were in biomarker-based Mayo stage II or III. GLS, brain natriuretic peptide, troponin, and mitral E/A ratio were identified as the strongest predictors of survival (P < .0001). Other predictors included sex, creatinine, free AL, wall thickness, and ejection fraction. Mayo stage was significantly associated with outcome, with 5-year survival of 93%, 72% and 31% in stage I, II, and III patients, respectively. GLS of 17% was identified as the value that best discriminated survivors from nonsurvivors, and the application of this cutoff value provided further mortality risk stratification within each Mayo stage. GLS is a strong predictor of survival in patients with AL amyloidosis undergoing HCT, potentially providing incremental value over serum cardiac biomarkers for risk stratification. GLS should be considered as a standard parameter along with serum cardiac biomarkers when evaluating eligibility for HCT or other investigational therapies. Copyright © 2017 American Society of Echocardiography. Published by Elsevier Inc. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Barth, R.F.; Matalka, K.Z.; Bailey, M.Q.

The present study was carried out to determine the efficacy of Boron Neutron Capture Therapy (BNCT) for intracerebral melanoma using nude rats, the human melanoma cell line MRA 27, and boronophenylalanine as the capture agent. MRA 27 cells (2 [times] 10[sup 5]) were implanted intracerebrally, and 30 days later, 120 mg of [sup 10]B-L-BPA were injected intraperitoneally into nude rats. Thirty days following implantation, tumor bearing rats were irradiated at the Brookhaven Medical Research Reactor. Six hours following administration of BPA, tumor, blood, and normal brain boron-10 levels were 23.7, 9.4, and 8.4 [mu]g/g respectively. Median survival time of untreatedmore » rats was 44 days compared to 76 days and 93 days for those receiving physical doses of 2.73 Gy and 3.64 Gy, respectively. Rats that have received both [sup 10]B-BPA and physical doses of 1.82, 2.73, or 3.64 Gy had median survival times of 170, 182, and 262 days, respectively. Forty percent of rats that had received the highest tumor dose (10.1 Gy) survived for > 300 days and in a replicate experiment 21% of the rats were longterm survivors (>220 days). Animals that received 12 Gy in a single dose or 18 Gy fractionated (2 Gy [times] 9) of gamma photons from a [sup 137]Cs source had median survival times of 86 and 79 days, respectively, compared to 47 days for untreated animals. Histopathologic examination of the brains of longterm surviving rats, euthanized at 8 or 16 months following BNCT, showed no residual tumor, but dense accumulations of melanin laden macrophages and minimal gliosis were observed. Significant prolongations in median survival time were noted in nude rats with intracerebral human melanoma that had received BNCT, thereby suggesting therapeutic efficacy. Large animal studies should be carried out to further assess BNCT of intracerebral melanoma before any human trials are contemplated. 49 refs., 7 figs., 2 tabs.« less

Clonogenic Assay: Adherent Cells

PubMed Central

Rafehi, Haloom; Orlowski, Christian; Georgiadis, George T.; Ververis, Katherine; El-Osta, Assam; Karagiannis, Tom C.

2011-01-01

The clonogenic (or colony forming) assay has been established for more than 50 years; the original paper describing the technique was published in 19561. Apart from documenting the method, the initial landmark study generated the first radiation-dose response curve for X-ray irradiated mammalian (HeLa) cells in culture1. Basically, the clonogenic assay enables an assessment of the differences in reproductive viability (capacity of cells to produce progeny; i.e. a single cell to form a colony of 50 or more cells) between control untreated cells and cells that have undergone various treatments such as exposure to ionising radiation, various chemical compounds (e.g. cytotoxic agents) or in other cases genetic manipulation. The assay has become the most widely accepted technique in radiation biology and has been widely used for evaluating the radiation sensitivity of different cell lines. Further, the clonogenic assay is commonly used for monitoring the efficacy of radiation modifying compounds and for determining the effects of cytotoxic agents and other anti-cancer therapeutics on colony forming ability, in different cell lines. A typical clonogenic survival experiment using adherent cells lines involves three distinct components, 1) treatment of the cell monolayer in tissue culture flasks, 2) preparation of single cell suspensions and plating an appropriate number of cells in petri dishes and 3) fixing and staining colonies following a relevant incubation period, which could range from 1-3 weeks, depending on the cell line. Here we demonstrate the general procedure for performing the clonogenic assay with adherent cell lines with the use of an immortalized human keratinocyte cell line (FEP-1811)2. Also, our aims are to describe common features of clonogenic assays including calculation of the plating efficiency and survival fractions after exposure of cells to radiation, and to exemplify modification of radiation-response with the use of a natural antioxidant formulation. PMID:21445039

Umbilical cord blood expansion with nicotinamide provides long-term multilineage engraftment.

PubMed

Horwitz, Mitchell E; Chao, Nelson J; Rizzieri, David A; Long, Gwynn D; Sullivan, Keith M; Gasparetto, Cristina; Chute, John P; Morris, Ashley; McDonald, Carolyn; Waters-Pick, Barbara; Stiff, Patrick; Wease, Steven; Peled, Amnon; Snyder, David; Cohen, Einat Galamidi; Shoham, Hadas; Landau, Efrat; Friend, Etty; Peleg, Iddo; Aschengrau, Dorit; Yackoubov, Dima; Kurtzberg, Joanne; Peled, Tony

2014-07-01

Delayed hematopoietic recovery is a major drawback of umbilical cord blood (UCB) transplantation. Transplantation of ex vivo-expanded UCB shortens time to hematopoietic recovery, but long-term, robust engraftment by the expanded unit has yet to be demonstrated. We tested the hypothesis that a UCB-derived cell product consisting of stem cells expanded for 21 days in the presence of nicotinamide and a noncultured T cell fraction (NiCord) can accelerate hematopoietic recovery and provide long-term engraftment. In a phase I trial, 11 adults with hematologic malignancies received myeloablative bone marrow conditioning followed by transplantation with NiCord and a second unmanipulated UCB unit. Safety, hematopoietic recovery, and donor engraftment were assessed and compared with historical controls. No adverse events were attributable to the infusion of NiCord. Complete or partial neutrophil and T cell engraftment derived from NiCord was observed in 8 patients, and NiCord engraftment remained stable in all patients, with a median follow-up of 21 months. Two patients achieved long-term engraftment with the unmanipulated unit. Patients transplanted with NiCord achieved earlier median neutrophil recovery (13 vs. 25 days, P < 0.001) compared with that seen in historical controls. The 1-year overall and progression-free survival rates were 82% and 73%, respectively. UCB-derived hematopoietic stem and progenitor cells expanded in the presence of nicotinamide and transplanted with a T cell-containing fraction contain both short-term and long-term repopulating cells. The results justify further study of NiCord transplantation as a single UCB graft. If long-term safety is confirmed, NiCord has the potential to broaden accessibility and reduce the toxicity of UCB transplantation. Clinicaltrials.gov NCT01221857. Gamida Cell Ltd.

Application of a nanoflare probe specific to a latency associated transcript for isolation of KHV latently infected cells

PubMed Central

Reed, Aimee N.; Putman, Timothy; Sullivan, Christopher; Jin, Ling

2015-01-01

One of the unique features of herpesvirus infection is latent infection following an initial exposure, which is characterized by viral genome persistence in a small fraction of cells within the latently infected tissue. Investigation of the mechanisms of herpesvirus latency has been very challenging in tissues with only a small fraction of cells that are latently infected. Cyprinid herpesvirus 3, also known as koi herpesvirus (KHV), is an important and deadly pathogen of koi and common carp, Cyprinus carpio. Acute infection can cause up to 100% mortality in exposed fish, and fish that survive the infection become latently infected. KHV becomes latent in a small percentage of B lymphocytes and can reactivate under stressful conditions. During latency, KHV ORF6 transcript is expressed in the latently infected B lymphocytes. In order to study KHV latent infection in cells that are only latently infected, a nanoflare probe specific to ORF6 RNA was used to separate KHV latently infected cells from total peripheral white blood cells (WBC). Using the ORF6 nanoflare probe, less than 1% of peripheral WBC was isolated from KHV latently infected koi. When this enriched population of WBC was examined by real-time PCR specific for KHV, it was estimated that about 1 to 2 copies of viral genome persists in the sorted cells. In addition, KHV ORF6 transcript was shown to be the major transcript expressed during latency by RNA-seq analysis. This study demonstrated that an RNA nanoflare probe could be used to enrich latently infected cells, which can subsequently be used to investigate the molecular mechanisms of KHV latency. PMID:26087404

Ablative Hypofractionated Radiation Therapy Enhances Non-Small Cell Lung Cancer Cell Killing via Preferential Stimulation of Necroptosis In Vitro and In Vivo.

PubMed

Wang, Huan-Huan; Wu, Zhi-Qiang; Qian, Dong; Zaorsky, Nicholas G; Qiu, Ming-Han; Cheng, Jing-Jing; Jiang, Chao; Wang, Juan; Zeng, Xian-Liang; Liu, Chun-Lei; Tian, Li-Jun; Ying, Guo-Guang; Meng, Mao-Bin; Hao, Xi-Shan; Yuan, Zhi-Yong

2018-05-01

To investigate how necroptosis (ie, programmed necrosis) is involved in killing of non-small cell lung cancer (NSCLC) after ablative hypofractionated radiation therapy (HFRT). Deoxyribonucleic acid damage, DNA repair, and the death form of NSCLC cells were assessed after radiation therapy. The overexpression and silencing of receptor-interacting protein kinases 3 (RIP3, a key protein involved activation of necroptosis)-stable NSCLC cell lines were successfully constructed. The form of cell death, the number and area of colonies, and the regulatory proteins of necroptosis were characterized after radiation therapy in vitro. Finally, NSCLC xenografts and patient specimens were used to examine involvement of necroptosis after ablative HFRT in vivo. Radiation therapy induced expected DNA damage and repair of NSCLC cell lines, but ablative HFRT at ≥10 Gy per fraction preferentially stimulated necroptosis in NSCLC cells and xenografts with high RIP3 expression, as characterized by induction and activation of RIP3 and mixed-lineage kinase domain-like protein and release of immune-activating chemokine high-mobility group box 1. In contrast, RNA interference of RIP3 attenuated ablative HFRT-induced necroptosis and activation of its regulatory proteins. Among central early-stage NSCLC patients receiving stereotactic body radiation therapy, high expression of RIP3 was associated with improved local control and progression-free survival (all P < .05). Ablative HFRT at ≥10 Gy per fraction enhances killing of NSCLC with high RIP3 expression via preferential stimulation of necroptosis. RIP3 may serve as a useful biomarker to predict favorable response to stereotactic body radiation therapy. Copyright © 2018 Elsevier Inc. All rights reserved.

Human skin cell fractions fail to self-organize within a gellan gum/hyaluronic acid matrix but positively influence early wound healing.

PubMed

Cerqueira, Mariana T; da Silva, Lucília P; Santos, Tírcia C; Pirraco, Rogério P; Correlo, Vitor M; Marques, Alexandra P; Reis, Rui L

2014-05-01

Split-thickness autografts still are the current gold standard to treat skin, upon severe injuries. Nonetheless, autografts are dependent on donor site availability and often associated to poor quality neoskin. The generation of dermal-epidermal substitutes by tissue engineering is seen as a promising strategy to overcome this problematic. However, solutions that can be safely and conveniently transplanted in one single surgical intervention are still very challenging as their production normally requires long culture time, and graft survival is many times compromised by delayed vascularization upon transplantation. This work intended to propose a strategy that circumvents the prolonged and laborious preparation period of skin substitutes and allows skin cells self-organization toward improved healing. Human dermal/epidermal cell fractions were entrapped directly from isolation within a gellan gum/hyaluronic acid (GG-HA) spongy-like hydrogel formed from an off-the-shelf dried polymeric network. Upon transplantation into full-thickness mice wounds, the proposed constructs accelerated the wound closure rate and re-epithelialization, as well as tissue neovascularization. A synergistic effect of the GG-HA matrix and the transplanted cells over those processes was demonstrated at early time points. Despite the human-derived and chimeric blood vessels found, the proposed matrix did not succeed in prolonging cells residence time and in sustaining the self-organization of transplanted human cells possibly due to primitive degradation. Despite this, the herein proposed approach open the opportunity to tackle wound healing at early stages contributing to re-epithelialization and neovascularization.

Human Skin Cell Fractions Fail to Self-Organize Within a Gellan Gum/Hyaluronic Acid Matrix but Positively Influence Early Wound Healing

PubMed Central

Cerqueira, Mariana T.; da Silva, Lucília P.; Santos, Tírcia C.; Pirraco, Rogério P.; Correlo, Vitor M.; Reis, Rui L.

2014-01-01

Split-thickness autografts still are the current gold standard to treat skin, upon severe injuries. Nonetheless, autografts are dependent on donor site availability and often associated to poor quality neoskin. The generation of dermal–epidermal substitutes by tissue engineering is seen as a promising strategy to overcome this problematic. However, solutions that can be safely and conveniently transplanted in one single surgical intervention are still very challenging as their production normally requires long culture time, and graft survival is many times compromised by delayed vascularization upon transplantation. This work intended to propose a strategy that circumvents the prolonged and laborious preparation period of skin substitutes and allows skin cells self-organization toward improved healing. Human dermal/epidermal cell fractions were entrapped directly from isolation within a gellan gum/hyaluronic acid (GG-HA) spongy-like hydrogel formed from an off-the-shelf dried polymeric network. Upon transplantation into full-thickness mice wounds, the proposed constructs accelerated the wound closure rate and re-epithelialization, as well as tissue neovascularization. A synergistic effect of the GG-HA matrix and the transplanted cells over those processes was demonstrated at early time points. Despite the human-derived and chimeric blood vessels found, the proposed matrix did not succeed in prolonging cells residence time and in sustaining the self-organization of transplanted human cells possibly due to primitive degradation. Despite this, the herein proposed approach open the opportunity to tackle wound healing at early stages contributing to re-epithelialization and neovascularization. PMID:24299468

Stereotactic Body Radiation Therapy Boost After Concurrent Chemoradiation for Locally Advanced Non-Small Cell Lung Cancer: A Phase 1 Dose Escalation Study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hepel, Jaroslaw T., E-mail: jhepel@lifespan.org; Department of Radiation Oncology, Tufts Medical Center, Tufts University, Boston, Massachusetts; Leonard, Kara Lynne

Purpose: Stereotactic body radiation therapy (SBRT) boost to primary and nodal disease after chemoradiation has potential to improve outcomes for advanced non-small cell lung cancer (NSCLC). A dose escalation study was initiated to evaluate the maximum tolerated dose (MTD). Methods and Materials: Eligible patients received chemoradiation to a dose of 50.4 Gy in 28 fractions and had primary and nodal volumes appropriate for SBRT boost (<120 cc and <60 cc, respectively). SBRT was delivered in 2 fractions after chemoradiation. Dose was escalated from 16 to 28 Gy in 2 Gy/fraction increments, resulting in 4 dose cohorts. MTD was defined when ≥2 of 6 patients permore » cohort experienced any treatment-related grade 3 to 5 toxicity within 4 weeks of treatment or the maximum dose was reached. Late toxicity, disease control, and survival were also evaluated. Results: Twelve patients (3 per dose level) underwent treatment. All treatment plans met predetermined dose-volume constraints. The mean age was 64 years. Most patients had stage III disease (92%) and were medically inoperable (92%). The maximum dose level was reached with no grade 3 to 5 acute toxicities. At a median follow-up time of 16 months, 1-year local-regional control (LRC) was 78%. LRC was 50% at <24 Gy and 100% at ≥24 Gy (P=.02). Overall survival at 1 year was 67%. Late toxicity (grade 3-5) was seen in only 1 patient who experienced fatal bronchopulmonary hemorrhage (grade 5). There were no predetermined dose constraints for the proximal bronchial-vascular tree (PBV) in this study. This patient's 4-cc PBV dose was substantially higher than that received by other patients in all 4 cohorts and was associated with the toxicity observed: 20.3 Gy (P<.05) and 73.5 Gy (P=.07) for SBRT boost and total treatment, respectively. Conclusions: SBRT boost to both primary and nodal disease after chemoradiation is feasible and well tolerated. Local control rates are encouraging, especially at doses ≥24 Gy in 2 fractions. Toxicity at the PBV is a concern but potentially can be avoided with strict dose-volume constraints.« less

Dissecting the T Cell Response: Proliferation Assays vs. Cytokine Signatures by ELISPOT

PubMed Central

Anthony, Donald D.; Milkovich, Kimberly A.; Zhang, Wenji; Rodriguez, Benigno; Yonkers, Nicole L.; Tary-Lehmann, Magdalena; Lehmann, Paul V.

2012-01-01

Chronic allograft rejection is in part mediated by host T cells that recognize allogeneic antigens on transplanted tissue. One factor that determines the outcome of a T cell response is clonal size, while another is the effector quality. Studies of alloimmune predictors of transplant graft survival have most commonly focused on only one measure of the alloimmune response. Because differing qualities and frequencies of the allospecific T cell response may provide distinctly different information we analyzed the relationship between frequency of soluble antigen and allo-antigen specific memory IFN-γ secreting CD4 and CD8 T cells, their ability to secrete IL-2, and their proliferative capacity, while accounting for cognate and bystander proliferation. The results show proliferative responses primarily reflect on IL-2 production by antigen-specific T cells, and that proliferating cells in such assays entail a considerable fraction of bystander cells. On the other hand, proliferation (and IL-2 production) did not reflect on the frequency of IFN-γ producing memory cells, a finding particularly accentuated in the CD8 T cell compartment. These data provide rationale for considering both frequency and effector function of pre-transplant T cell reactivity when analyzing immune predictors of graft rejection. PMID:24710419

Cyclic, low-dose total body irradiation for metastatic neuroblastoma

DOE Office of Scientific and Technical Information (OSTI.GOV)

D'Angio, G.J.; Evans, A.E.

1983-12-01

Total body irradiation (TBI) can be thought of as a systemic anticancer agent. It therefore might best be given like an adjuvant drug, i.e., in tolerable doses, cyclically. The therapeutic ratio between normal bone marrow stem cells and suitably sensitive cancer cells should be widened by these means. Fourteen children with advanced (Stage IV) neuroblastomas were given 100-150 rad TBI in 50 rad daily fractions along with each three-week cycle of standard triple-agent chemotherapy (vincristine, DTIC, cyclophosphamide). Two patients died of toxicity and one is still undergoing therapy. Four of the remaining 12 survive free of disease for 12+ tomore » 31+ months. The regimen is well tolerated, but prolonged, pronounced bone marrow depression, especially thrombocytopenia, commonly occurs after doses of 300-450 rad.« less

The effect of dimethyl sulfoxide on the induction of DNA strand breaks in plasmid DNA and colony formation of PC Cl3 mammalian cells by alpha-, beta-, and Auger electron emitters (223)Ra, (188)Re, and (99m)Tc.

PubMed

Runge, Roswitha; Oehme, Liane; Kotzerke, Jörg; Freudenberg, Robert

2016-12-01

DNA damage occurs as a consequence of both direct and indirect effects of ionizing radiation. The severity of DNA damage depends on the physical characteristics of the radiation quality, e.g., the linear energy transfer (LET). There are still contrary findings regarding direct or indirect interactions of high-LET emitters with DNA. Our aim is to determine DNA damage and the effect on cellular survival induced by (223)Ra compared to (188)Re and (99m)Tc modulated by the radical scavenger dimethyl sulfoxide (DMSO). Radioactive solutions of (223)Ra, (188)Re, or (99m)Tc were added to either plasmid DNA or to PC Cl3 cells in the absence or presence of DMSO. Following irradiation, single strand breaks (SSB) and double strand breaks (DSB) in plasmid DNA were analyzed by gel electrophoresis. To determine the radiosensitivity of the rat thyroid cell line (PC Cl3), survival curves were performed using the colony formation assay. Exposure to 120 Gy of (223)Ra, (188)Re, or (99m)Tc leads to maximal yields of SSB (80 %) in plasmid DNA. Irradiation with 540 Gy (223)Ra and 500 Gy (188)Re or (99m)Tc induced 40, 28, and 64 % linear plasmid conformations, respectively. DMSO prevented the SSB and DSB in a similar way for all radionuclides. However, with the α-emitter (223)Ra, a low level of DSB could not be prevented by DMSO. Irradiation of PC Cl3 cells with (223)Ra, (188)Re, and (99m)Tc pre-incubated with DMSO revealed enhanced survival fractions (SF) in comparison to treatment without DMSO. Protection factors (PF) were calculated using the fitted survival curves. These factors are 1.23 ± 0.04, 1.20 ± 0.19, and 1.34 ± 0.05 for (223)Ra, (188)Re, and (99m)Tc, respectively. For (223)Ra, as well as for (188)Re and (99m)Tc, dose-dependent radiation effects were found applicable for plasmid DNA and PC Cl3 cells. The radioprotection by DMSO was in the same range for high- and low-LET emitter. Overall, the results indicate the contribution of mainly indirect radiation effects for each of the radionuclides regarding DNA damage and cell survival. In summary, our findings may contribute to fundamental knowledge about the α-particle induced DNA damage.

Assessment of the Forward Contamination Risk of Mars by Clean Room Isolates from Space-Craft Assembly Facilities through Aeolian Transport - a Model Study.

PubMed

van Heereveld, Luc; Merrison, Jonathan; Nørnberg, Per; Finster, Kai

2017-06-01

The increasing number of missions to Mars also increases the risk of forward contamination. Consequently there is a need for effective protocols to ensure efficient protection of the Martian environment against terrestrial microbiota. Despite the fact of constructing sophisticated clean rooms for spacecraft assembly a 100 % avoidance of contamination appears to be impossible. Recent surveys of these facilities have identified a significant number of microbes belonging to a variety of taxonomic groups that survive the harsh conditions of clean rooms. These microbes may have a strong contamination potential, which needs to be investigate to apply efficient decontamination treatments. In this study we propose a series of tests to evaluate the potential of clean room contaminants to survive the different steps involved in forward contamination. We used Staphylococcus xylosus as model organism to illustrate the different types of stress that potential contaminants will be subjected to on their way from the spacecraft onto the surface of Mars. Staphylococcus xylosus is associated with human skin and commonly found in clean rooms and could therefore contaminate the spacecraft as a result of human activity during the assembling process. The path the cell will take from the surface of the spacecraft onto the surface of Mars was split into steps representing different stresses that include desiccation, freezing, aeolian transport in a Martian-like atmosphere at Martian atmospheric pressure, and UV radiation climate. We assessed the surviving fraction of the cellular population after each step by determining the integrated metabolic activity of the survivor population by measuring their oxygen consumption rate. The largest fraction of the starting culture (around 70 %) was killed during desiccation, while freezing, Martian vacuum and short-term UV radiation only had a minor additional effect on the survivability of Staphylococcus xylosus. The study also included a simulation of atmospheric transport on Martian dust, which did not significantly alter the metabolic potential of the cells. The high survival potential of skin microbes, which are not among the most robust isolates, clearly underlines the necessity for efficient decontamination protocols and of adequate planetary protection measures. Thus we propose a series of tests to be included into the description of isolates from spacecraft assembly clean rooms in order to assess the forward contamination potential of the specific isolate and to categorize the risk level according to the organisms survival potential. We are aware that the tests that we propose do not exhaust the types of challenges that the microbes would meet on their way and therefore the series of tests is open to being extended.

Assessment of the Forward Contamination Risk of Mars by Clean Room Isolates from Space-Craft Assembly Facilities through Aeolian Transport - a Model Study

NASA Astrophysics Data System (ADS)

van Heereveld, Luc; Merrison, Jonathan; Nørnberg, Per; Finster, Kai

2017-06-01

The increasing number of missions to Mars also increases the risk of forward contamination. Consequently there is a need for effective protocols to ensure efficient protection of the Martian environment against terrestrial microbiota. Despite the fact of constructing sophisticated clean rooms for spacecraft assembly a 100 % avoidance of contamination appears to be impossible. Recent surveys of these facilities have identified a significant number of microbes belonging to a variety of taxonomic groups that survive the harsh conditions of clean rooms. These microbes may have a strong contamination potential, which needs to be investigate to apply efficient decontamination treatments. In this study we propose a series of tests to evaluate the potential of clean room contaminants to survive the different steps involved in forward contamination. We used Staphylococcus xylosus as model organism to illustrate the different types of stress that potential contaminants will be subjected to on their way from the spacecraft onto the surface of Mars. Staphylococcus xylosus is associated with human skin and commonly found in clean rooms and could therefore contaminate the spacecraft as a result of human activity during the assembling process. The path the cell will take from the surface of the spacecraft onto the surface of Mars was split into steps representing different stresses that include desiccation, freezing, aeolian transport in a Martian-like atmosphere at Martian atmospheric pressure, and UV radiation climate. We assessed the surviving fraction of the cellular population after each step by determining the integrated metabolic activity of the survivor population by measuring their oxygen consumption rate. The largest fraction of the starting culture (around 70 %) was killed during desiccation, while freezing, Martian vacuum and short-term UV radiation only had a minor additional effect on the survivability of Staphylococcus xylosus. The study also included a simulation of atmospheric transport on Martian dust, which did not significantly alter the metabolic potential of the cells. The high survival potential of skin microbes, which are not among the most robust isolates, clearly underlines the necessity for efficient decontamination protocols and of adequate planetary protection measures. Thus we propose a series of tests to be included into the description of isolates from spacecraft assembly clean rooms in order to assess the forward contamination potential of the specific isolate and to categorize the risk level according to the organisms survival potential. We are aware that the tests that we propose do not exhaust the types of challenges that the microbes would meet on their way and therefore the series of tests is open to being extended.

Evaluation of two (125)I-radiolabeled acridine derivatives for Auger-electron radionuclide therapy of melanoma.

PubMed

Gardette, Maryline; Viallard, Claire; Paillas, Salomé; Guerquin-Kern, Jean-Luc; Papon, Janine; Moins, Nicole; Labarre, Pierre; Desbois, Nicolas; Wong-Wah-Chung, Pascal; Palle, Sabine; Wu, Ting-Di; Pouget, Jean-Pierre; Miot-Noirault, Elisabeth; Chezal, Jean-Michel; Degoul, Francoise

2014-08-01

We previously selected two melanin-targeting radioligands [(125)I]ICF01035 and [(125)I]ICF01040 for melanoma-targeted (125)I radionuclide therapy according to their pharmacological profile in mice bearing B16F0 tumors. Here we demonstrate in vitro that these compounds present different radiotoxicities in relation to melanin and acidic vesicle contents in B16F0, B16F0 PTU and A375 cell lines. ICF01035 is effectively observed in nuclei of achromic (A375) melanoma or in melanosomes of melanized melanoma (B16F0), while ICF01040 stays in cytoplasmic vesicles in both cells. [(125)I]ICF01035 induced a similar survival fraction (A50) in all cell lines and led to a significant decrease in S-phase cells in amelanotic cell lines. [(125)I]ICF01040 induced a higher A50 in B16 cell lines compared to [(125)I]ICF01035 ones. [(125)I]ICF01040 induced a G2/M blockade in both A375 and B16F0 PTU, associated with its presence in cytoplasmic acidic vesicles. These results suggest that the radiotoxicity of [(125)I]ICF01035 and [(125)I]ICF01040 are not exclusively reliant on DNA alterations compatible with γ rays but likely result from local dose deposition (Auger electrons) leading to toxic compound leaks from acidic vesicles. In vivo, [(125)I]ICF01035 significantly reduced the number of B16F0 lung colonies, enabling a significant increase in survival of the treated mice. Targeting melanosomes or acidic vesicles is thus an option for future melanoma therapy.

Proliferation and apoptosis in malignant and normal cells in B-cell non-Hodgkin's lymphomas.

PubMed Central

Stokke, T.; Holte, H.; Smedshammer, L.; Smeland, E. B.; Kaalhus, O.; Steen, H. B.

1998-01-01

We have examined apoptosis and proliferation in lymph node cell suspensions from patients with B-cell non-Hodgkin's lymphoma using flow cytometry. A method was developed which allowed estimation of the fractions of apoptotic cells and cells in the S-phase of the cell cycle simultaneously with tumour-characteristic light chain expression. Analysis of the tumour S-phase fraction and the tumour apoptotic fraction in lymph node cell suspensions from 95 B-cell non-Hodgkin's lymphoma (NHL) patients revealed a non-normal distribution for both parameters. The median fraction of apoptotic tumour cells was 1.1% (25 percentiles 0.5%, 2.7%). In the same samples, the median fraction of apoptotic normal cells was higher than for the tumour cells (1.9%; 25 percentiles 0.7%, 4.0%; P = 0.03). The median fraction of tumour cells in S-phase was 1.4% (25 percentiles 0.8%, 4.8%), the median fraction of normal cells in S-phase was significantly lower than for the tumour cells (1.0%; 25 percentiles 0.6%, 1.9%; P = 0.004). When the number of cases was plotted against the logarithm of the S-phase fraction of the tumour cells, a distribution with two Gaussian peaks was needed to fit the data. One peak was centred around an S-phase fraction of 0.9%; the other was centred around 7%. These peaks were separated by a valley at approximately 3%, indicating that the S-phase fraction in NHL can be classified as 'low' (< 3%) or 'high' (> 3%), independent of the median S-phase fraction. The apoptotic fractions were log-normally distributed. The median apoptotic fraction was higher (1.5%) in the 'high' S-phase group than in the 'low' S-phase group (0.8%; P = 0.02). However, there was no significant correlation between the two parameters (P > 0.05). PMID:9667654

High Dose Rate Brachytherapy in Two 9 Gy Fractions in the Treatment of Locally Advanced Cervical Cancer - a South Indian Institutional Experience.

PubMed

Ghosh, Saptarshi; Rao, Pamidimukkala Bramhananda; Kotne, Sivasankar

2015-01-01

Although 3D image based brachytherapy is currently the standard of treatment in cervical cancer, most of the centres in developing countries still practice orthogonal intracavitary brachytherapy due to financial constraints. The quest for optimum dose and fractionation schedule in high dose rate (HDR) intracavitary brachytherapy (ICBT) is still ongoing. While the American Brachytherapy Society recommends four to eight fractions of each less than 7.5 Gy, there are some studies demonstrating similar efficacy and comparable toxicity with higher doses per fraction. To assess the treatment efficacy and late complications of HDR ICBT with 9 Gy per fraction in two fractions. This is a prospective institutional study in Southern India carried on from 1st June 2012 to 31st July 2014. In this period, 76 patients of cervical cancer satisfying our inclusion criteria were treated with concurrent chemo-radiation following ICBT with 9 Gy per fraction in two fractions, five to seven days apart. The median follow-up period in the study was 24 months (range 10.6 - 31.2 months). The 2 year actuarial local control rate, disease-free survival and overall survival were 88.1%, 84.2% and 81.8% respectively. Although 38.2% patients suffered from late toxicity, only 3 patients had grade III late toxicity. In our experience, HDR brachytherapy with 9 Gy per fraction in two fractions is an effective dose fractionation for the treatment of cervical cancer with acceptable toxicity.

Best dispersal strategies in spatially heterogeneous environments: optimization of the principal eigenvalue for indefinite fractional Neumann problems.

PubMed

Pellacci, Benedetta; Verzini, Gianmaria

2018-05-01

We study the positive principal eigenvalue of a weighted problem associated with the Neumann spectral fractional Laplacian. This analysis is related to the investigation of the survival threshold in population dynamics. Our main result concerns the optimization of such threshold with respect to the fractional order [Formula: see text], the case [Formula: see text] corresponding to the standard Neumann Laplacian: when the habitat is not too fragmented, the principal positive eigenvalue can not have local minima for [Formula: see text]. As a consequence, the best strategy for survival is either following the diffusion with [Formula: see text] (i.e. Brownian diffusion), or with the lowest possible s (i.e. diffusion allowing long jumps), depending on the size of the domain. In addition, we show that analogous results hold for the standard fractional Laplacian in [Formula: see text], in periodic environments.

Fra-1 promotes growth and survival in RAS-transformed thyroid cells by controlling cyclin A transcription

PubMed Central

Casalino, Laura; Bakiri, Latifa; Talotta, Francesco; Weitzman, Jonathan B; Fusco, Alfredo; Yaniv, Moshe; Verde, Pasquale

2007-01-01

Fra-1 is frequently overexpressed in epithelial cancers and implicated in invasiveness. We previously showed that Fra-1 plays crucial roles in RAS transformation in rat thyroid cells and mouse fibroblasts. Here, we report a novel role for Fra-1 as a regulator of mitotic progression in RAS-transformed thyroid cells. Fra-1 expression and phosphorylation are regulated during the cell cycle, peaking at G2/M. Knockdown of Fra-1 caused a proliferative block and apoptosis. Although most Fra-1-knockdown cells accumulated in G2, a fraction of cells entering M-phase underwent abortive cell division and exhibited hallmarks of genomic instability (micronuclei, lagging chromosomes and anaphase bridges). Furthermore, we established a link between Fra-1 and the cell-cycle machinery by identifying cyclin A as a novel transcriptional target of Fra-1. During the cell cycle, Fra-1 was recruited to the cyclin A gene (ccna2) promoter, binding to previously unidentified AP-1 sites and the CRE. Fra-1 also induced the expression of JunB, which in turn interacts with the cyclin A promoter. Hence, Fra-1 induction is important in thyroid tumorigenesis, critically regulating cyclin expression and cell-cycle progression. PMID:17347653

Unravelling the potential of a new uracil phosphoribosyltransferase (UPRT) from Arabidopsis thaliana in sensitizing HeLa cells towards 5-fluorouracil.

PubMed

Narayanan, Sharmila; Sanpui, Pallab; Sahoo, Lingaraj; Ghosh, Siddhartha Sankar

2016-10-01

In silico studies with uracil phosphoribosyltransferase from Arabidopsis thaliana (AtUPRT) revealed its lower binding energies for uracil and 5-fluorouracil (5-FU) as compared to those of bacterial UPRT indicating the prospective of AtUPRT in gene therapy implications. Hence, AtUPRT was cloned and stably expressed in cervical cancer cells (HeLa) to investigate the effect of prodrug 5-FU on these transfected cancer cells. The treatment of AtUPRT-expressing HeLa (HeLa-UPP) cells with 5-FU for 72h resulted in significant decrease in cell viability. Moreover, 5-FU was observed to induce apoptosis and perturb mitochondrial membrane potential in HeLa-UPP cells. While cell cycle analysis revealed significant S-phase arrest as a result of 5-FU treatment in HeLa-UPP cells, quantitative gene expression analysis demonstrated simultaneous upregulation of important cell cycle related genes, cyclin D1 and p21. The survival fractions of non-transfected, vector-transfected and AtUPRT-transfected HeLa cells, following 5-FU treatment, were calculated to be 0.425, 0.366 and 0.227, respectively. Copyright © 2016 Elsevier B.V. All rights reserved.

Stereotactic Body Radiation Therapy for Oligometastatic Prostate Cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Muldermans, Jonathan L.; Romak, Lindsay B.; Kwon, Eugene D.

Purpose: To review outcomes of patients with oligometastatic prostate cancer (PCa) treated with stereotactic body radiation therapy (SBRT) and to identify variables associated with local failure. Methods and Materials: We retrospectively reviewed records of patients treated with SBRT for oligometastatic PCa. Metastasis control (ie, control of the treated lesion, MC), biochemical progression-free survival, distant progression-free survival, and overall survival were estimated with the Kaplan-Meier method. Results: Sixty-six men with 81 metastatic PCa lesions, 50 of which were castrate-resistant, were included in the analysis. Lesions were in bone (n=74), lymph nodes (n=6), or liver (n=1). Stereotactic body radiation therapy was deliveredmore » in 1 fraction to 71 lesions (88%), at a median dose of 16 Gy (range, 16-24 Gy). The remaining lesions received 30 Gy in 3 fractions (n=6) or 50 Gy in 5 fractions (n=4). Median follow-up was 16 months (range, 3-49 months). Estimated MC at 2 years was 82%. Biochemical progression-free survival, distant progression-free survival, and overall survival were 54%, 45%, and 83%, respectively. On multivariate analysis, only the dose of SBRT was significantly associated with MC; lesions treated with 16 Gy had 58% MC, and those treated with ≥18 Gy had 95% MC at 2 years (P≤.001). At 2 years, MC for lesions treated with 18 Gy (n=21) was 88%. No patient treated with ≥18 Gy in a single fraction or with any multifraction regimen had local failure. Six patients (9%) had grade 1 pain flare, and 2 (3%) had grade 2 pain flare. No grade 2 or greater late toxicities were reported. Conclusions: Stereotactic body radiation therapy for patients with oligometastatic prostate cancer provided optimal metastasis control and acceptable toxicity with doses ≥18 Gy. Biochemical progression-free survival was 54% at 16 months with the inclusion of SBRT in the treatment regimen. Stereotactic body radiation therapy should be considered in patients with castration-refractory, oligometastatic prostate cancer who have limited options for systemic therapy.« less

Nuclear location of tumor suppressor protein maspin inhibits proliferation of breast cancer cells without affecting proliferation of normal epithelial cells

PubMed Central

2014-01-01

Background Maspin, which is classified as a tumor suppressor protein, is downregulated in many types of cancer. Several studies have suggested potential anti-proliferative activity of maspin as well as sensitizing activity of maspin for therapeutic cytotoxic agents in breast cancer tissue culture and animal models. All of the experimental data gathered so far have been based on studies with maspin localized cytoplasmically, while maspin in breast cancer tumor cells may be located in the cytoplasm, nucleus or both. In this study, the effect of maspin cytoplasmic and nuclear location and expression level on breast cancer proliferation and patient survival was studied. Methods Tissue sections from 166 patients with invasive ductal breast cancer were stained by immunohistochemistry for maspin and Ki-67 protein. The localization and expression level of maspin were correlated with estimated patient overall survival and percent of Ki-67-positive cells. In further studies, we created constructs for transient transfection of maspin into breast cancer cells with targeted cytoplasmic and nuclear location. We analyzed the effect of maspin location in normal epithelial cell line MCF10A and three breast cancer cell lines - MCF-7, MDA-MB-231 and SKBR-3 - by immunofluorescence and proliferation assay. Results We observed a strong positive correlation between moderate and high nuclear maspin level and survival of patients. Moreover, a statistically significant negative relationship was observed between nuclear maspin and Ki-67 expression in patients with invasive ductal breast cancer. Spearman’s correlation analysis showed a negative correlation between level of maspin localized in nucleus and percentage of Ki-67 positive cells. No such differences were observed in cells with cytoplasmic maspin. We found a strong correlation between nuclear maspin and loss of Ki-67 protein in breast cancer cell lines, while there was no effect in normal epithelial cells from breast. The anti-proliferative effect of nuclear maspin on breast cancer cells was statistically significant in comparison to cytoplasmic maspin. Conclusions Our results suggest that nuclear maspin localization may be a prognostic factor in breast cancer and may have a strong therapeutic potential in gene therapy. Moreover, these data provide a new insight into the role of cytoplasmic and nuclear fractions of maspin in breast cancer. PMID:24581141

Radical-intent hypofractionated radiotherapy for locally advanced non-small-cell lung cancer: a systematic review of the literature.

PubMed

Kaster, Tyler S; Yaremko, Brian; Palma, David A; Rodrigues, George B

2015-03-01

To identify survival and toxicity characteristics associated with radical-intent hypofractionated radiotherapy for the treatment of stage III non-small-cell lung cancer (NSCLC). Relevant studies were identified from a systematic PubMed search of articles published between January 1990 and January 2014. All studies were peer reviewed and included both retrospective and prospective studies of NSCLC patients being treated with radical hypofractionated radiotherapy. Data on overall survival (OS) and toxicity were extracted from each of the studies where available. Of 685 studies initially identified by the search, a total of 33 studies were found to be relevant and were included in this systematic review. The number of fractions ranged from 15 to 35, the dose per fraction ranged from 2.3 to 3.5 Gy, and the delivered dose ranged from 45.0 to 85.5 Gy. Fifteen of the studies included concurrent chemotherapy, while 18 did not. OS was found to be associated with tumor biological effective dose, with the Pearson correlation coefficient ranging from 0.34 to 0.48. For both concurrent and nonconcurrent chemoradiotherapy acute pulmonary, late esophageal and late pulmonary incidences of toxicity ranged from 1.2% to 12.2%, but had 95% confidence intervals that included zero. The greatest incidence of toxicity was acute esophageal toxicity at 14.9% (95% confidence interval, 0.7%, 29.1%). There is a moderate linear relationship between biological effective dose and OS, and greater acute esophageal toxicity with concurrent chemotherapy. Improving outcomes in stage III NSCLC may involve some form of hypofractionation in the context of systemic concurrent therapy. Copyright © 2015 Elsevier Inc. All rights reserved.

Identification of pre-leukaemic haematopoietic stem cells in acute leukaemia.

PubMed

Shlush, Liran I; Zandi, Sasan; Mitchell, Amanda; Chen, Weihsu Claire; Brandwein, Joseph M; Gupta, Vikas; Kennedy, James A; Schimmer, Aaron D; Schuh, Andre C; Yee, Karen W; McLeod, Jessica L; Doedens, Monica; Medeiros, Jessie J F; Marke, Rene; Kim, Hyeoung Joon; Lee, Kwon; McPherson, John D; Hudson, Thomas J; Brown, Andrew M K; Yousif, Fouad; Trinh, Quang M; Stein, Lincoln D; Minden, Mark D; Wang, Jean C Y; Dick, John E

2014-02-20

In acute myeloid leukaemia (AML), the cell of origin, nature and biological consequences of initiating lesions, and order of subsequent mutations remain poorly understood, as AML is typically diagnosed without observation of a pre-leukaemic phase. Here, highly purified haematopoietic stem cells (HSCs), progenitor and mature cell fractions from the blood of AML patients were found to contain recurrent DNMT3A mutations (DNMT3A(mut)) at high allele frequency, but without coincident NPM1 mutations (NPM1c) present in AML blasts. DNMT3A(mut)-bearing HSCs showed a multilineage repopulation advantage over non-mutated HSCs in xenografts, establishing their identity as pre-leukaemic HSCs. Pre-leukaemic HSCs were found in remission samples, indicating that they survive chemotherapy. Therefore DNMT3A(mut) arises early in AML evolution, probably in HSCs, leading to a clonally expanded pool of pre-leukaemic HSCs from which AML evolves. Our findings provide a paradigm for the detection and treatment of pre-leukaemic clones before the acquisition of additional genetic lesions engenders greater therapeutic resistance.

Getting away with murder: how do the BCL-2 family of proteins kill with immunity?

PubMed Central

Renault, Thibaud T.; Chipuk, Jerry E.

2013-01-01

About 1 million per second is the number of white blood cells the adult human body produces. However, only a small fraction of them will survive as the majority is eliminated through a genetically controlled form of cell death referred to as apoptosis. This review places into perspective recent studies pertaining to the BCL-2 family of proteins as critical regulators of the development and function of the immune system, with particular attention on B cell and T cell biology. Here we discuss how elegant murine model systems have revealed the major contributions of the BCL-2 family in establishing an effective immune system. Moreover, we highlight some key regulatory pathways that influence the expression, function, and stability of individual BCL-2 family members, and discuss their role in immunity. From deadly methods to more gentle manners, the final portion of the review discusses the non-apoptotic functions of the BCL-2 family and how they pertain to the control of immunity. PMID:23527542

Development of a Cytokine-Modified Allogeneic Whole Cell Pancreatic Cancer Vaccine

PubMed Central

Laheru, Dan; Biedrzycki, Barbara; Jaffee, Elizabeth M.

2015-01-01

Management of patients with pancreatic cancer is a multidisciplinary approach that presents enormous challenges to the clinician. Overall 5-year survival for all patients remains <3%. Symptoms of early pancreas cancer are nonspecific. As such, only a fraction of patients are candidates for surgery. While surgical resection provides the only curative option, most patients will develop tumor recurrence and die of their disease. To date, the clinical benefits of chemotherapy and radiation therapy have been important but have led to modest improvements. Tumor vaccines have the potential to specifically target the needle of pancreas cancer cells amidst the haystack of normal tissue. The discovery of pancreas tumor-specific antigens and the subsequent ability to harness this technology has become an area of intense interest for tumor immunologists and clinicians alike. Without knowledge of specific antigen targets, the whole tumor cell represents the best source of immunizing antigens. This chapter will focus on the development of whole tumor cell vaccine strategies for pancreas cancer. PMID:23359154

Methods for assisting recovery of damaged brain and spinal cord and treating various diseases using arrays of x-ray microplanar beams

DOEpatents

Dilmanian, F Avraham [Yaphank, NY; Anchel, David J [Rocky Point, NY; Gaudette, Glenn [Holden, MA; Romanelli, Pantaleo [Monteroduni, IT; Hainfeld, James [Shoreham, NY

2010-06-29

A method of assisting recovery of an injury site of the central nervous system (CNS) or treating a disease includes providing a therapeutic dose of X-ray radiation to a target volume through an array of parallel microplanar beams. The dose to treat CNS injury temporarily removes regeneration inhibitors from the irradiated site. Substantially unirradiated cells surviving between beams migrate to the in-beam portion and assist recovery. The dose may be staggered in fractions over sessions using angle-variable intersecting microbeam arrays (AVIMA). Additional doses are administered by varying the orientation of the beams. The method is enhanced by injecting stem cells into the injury site. One array or the AVIMA method is applied to ablate selected cells in a target volume associated with disease for palliative or curative effect. Atrial fibrillation is treated by irradiating the atrial wall to destroy myocardial cells while continuously rotating the subject.

Boron neutron capture therapy induces cell cycle arrest and cell apoptosis of glioma stem/progenitor cells in vitro.

PubMed

Sun, Ting; Zhang, Zizhu; Li, Bin; Chen, Guilin; Xie, Xueshun; Wei, Yongxin; Wu, Jie; Zhou, Youxin; Du, Ziwei

2013-08-06

Glioma stem cells in the quiescent state are resistant to clinical radiation therapy. An almost inevitable glioma recurrence is due to the persistence of these cells. The high linear energy transfer associated with boron neutron capture therapy (BNCT) could kill quiescent and proliferative cells. The present study aimed to evaluate the effects of BNCT on glioma stem/progenitor cells in vitro. The damage induced by BNCT was assessed using cell cycle progression, apoptotic cell ratio and apoptosis-associated proteins expression. The surviving fraction and cell viability of glioma stem/progenitor cells were decreased compared with differentiated glioma cells using the same boronophenylalanine pretreatment and the same dose of neutron flux. BNCT induced cell cycle arrest in the G2/M phase and cell apoptosis via the mitochondrial pathway, with changes in the expression of associated proteins. Glioma stem/progenitor cells, which are resistant to current clinical radiotherapy, could be effectively killed by BNCT in vitro via cell cycle arrest and apoptosis using a prolonged neutron irradiation, although radiosensitivity of glioma stem/progenitor cells was decreased compared with differentiated glioma cells when using the same dose of thermal neutron exposure and boronophenylalanine pretreatment. Thus, BNCT could offer an appreciable therapeutic advantage to prevent tumor recurrence, and may become a promising treatment in recurrent glioma.

[Non-metastatic clear cell renal cancer: dependence of the tumour stage on clinico-anatomic and morphologic factors; prognostic value of macro- and karyometric characteristics].

PubMed

Iurin, A G

2010-01-01

Non-metastatic clear-cell renal cancer: dependence of the tumour stage on clinico-anatomic and morphologic factors; prognostic value of macro- and karyometric characteristics Sankt Peterburg Pathology Bureau, Sankt Peterburg It was shown based on multivariate regression analysis that pT1a3bN0MO stages of non-metastatic clear-cell renal cancer significantly correlate not only with the tumor size and invasion into the fatty tissue and/or renal vein but also with the invasion into the renal capsule and with the mean maximum diameter and mean nucleus area of tumor cells. There was no correlation of clear-cell renal cancer stages with tumor proliferative activity, gene p53 mutation, oncosuppressor gene PTEN expression, fraction of tumour clear-cell component, and such clinical characteristics as patients' sex, age, and body mass index. Taking into account statistically significant differences between the patients' survival rates, the regression equations developed in this work may be used for the prediction of disease outcome.

Re-Irradiation of Locoregional NSCLC Recurrence Using Robotic Stereotactic Body Radiotherapy.

PubMed

Ceylan, Cemile; Hamacı, Andaç; Ayata, Hande; Berberoglu, Kezban; Kılıç, Ayhan; Güden, Metin; Engin, Kayıhan

2017-01-01

We evaluated the efficacy, toxicity, and dose responses of re-irradiation with stereotactic body radiotherapy (SBRT) in patients with recurrent non- small cell lung cancer (NSCLC) after previous irradiation. 28 patients were included. Previous median radiation doses were 54 and 66 Gy. The median interval time between previous radiotherapy and SBRT was 14 months. The median follow-up time after SBRT was 9 months (range 3-93 months). To evaluate the effectiveness of SBRT, local control, overall survival, and treatment-related toxicity were reported. SBRT doses and fractionation ranged from 60 to 30 Gy and from 3 to 8, respectively, according to previous doses, location of the recurrence, and interval time. 65% of tumor recurrences overlapped with previous treatment, while 35% of tumors recurred outside of the previous treatment. 4 patients had local progression after SBRT at their first follow-up. The Kaplan-Meier estimates of the 1- and 2-year actuarial overall survival were 71 and 42%, respectively. The mean survival following SBRT was 32.8 months, and the median survival was 21 months. No grade 3 or higher toxicities were observed. Robotic SBRT is a tolerable treatment option with manageable toxicity which can be used with radical or palliative intent in carefully selected patients with locally recurrent tumors after previous irradiation. © 2017 S. Karger GmbH, Freiburg.

Baseline Cardiopulmonary Function as an Independent Prognostic Factor for Survival of Inoperable Non-Small-Cell Lung Cancer After Concurrent Chemoradiotherapy: A Single-Center Analysis of 161 Cases

DOE Office of Scientific and Technical Information (OSTI.GOV)

Semrau, Sabine, E-mail: sabine.semrau@uk-erlangen.d; Department of Radiation Therapy, University of Rostock, Suedring, Rostock; Klautke, Gunther

2011-01-01

Purpose: Little is known about the effects of cardiopulmonary function on the prognosis of concurrent chemoradiotherapy in patients with inoperable non-small-cell lung cancer (NSCLC). Methods and Materials: A retrospective analysis of the effects of tumor- and patient-related factors and parameters of cardiopulmonary function and heart morphology on the feasibility, toxicity, and prognosis was performed. Results: Cardiopulmonary function had no effect on the toxicity or feasibility of treatment; effects on survival were observed in the univariate analysis. Median survival varied as follows: cardiac function: 13.0 {+-} 1.6 months for left ventricular ejection fraction (LVEF) > 50% vs. 10.0 {+-} 1.9 monthsmore » for LVEF {<=} 50% (p = 0.003); pulmonary function: 16.0 {+-} 0.6 months for no lung function deficits (vital capacity [VC]{>=} 60%, forced expiratory volume in 1 s {>=} 80%, and diffusing capacity of the lung for carbon monoxide (DLCO) {>=}60%) vs. 14.0 {+-} 1.5 months for one or two function deficits vs. 8.0 {+-} 1.5 months for three lung function deficits (p = 0.001); T stage: 19.0 {+-} 3.1 months for rcT0/cT1/cT2 vs. 12.0 {+-} 0.8 months for cT3/cT4 (p = 0.039); and age: 11.0 {+-} 1.5 months for <60 years vs. 18.0 {+-} 2.5 months for 60-69 years vs. 12.0 {+-} 1.2 months for {>=}70 years (p = 0.008). Prognostic factors identified in the multivariate analysis were LVEF {<=}50% (p = 0.043; hazard ratio [HR], 1.74), reduced pulmonary function (p = 0.001; HR, 1.71 or 5.05) and T stage (p = 0.026; HR: 1.71). Conclusions: In addition to T-stage, cardiac and pulmonary function variables affected the survival of non-small-cell lung cancer patients after chemoradiotherapy.« less

Prospective, open, multicentre Phase I/II trial to assess safety and efficacy of neoadjuvant radiochemotherapy with docetaxel and cisplatin for esophageal carcinoma.

PubMed

Ma, Hong-Bing; Di, Zheng-Li; Wen, Jiao; Ke, Yue; Sun, Xiaodong; Ren, Juan

2015-02-01

Esophageal squamous cell carcinoma is increasingly treated with trimodality therapy. The objective of this Phase I/II clinical study is to assess the efficacy and safety of neoadjuvant radiochemotherapy with docetaxel and cisplatin and radiotherapy in patients with esophagectomy for locally advanced squamous cell carcinoma of the esophagus with neoadjuvant chemoradiotherapy. Patients with esophageal squamous cell carcinoma received radiochemotherapy (50 Gy/25 fractions during Weeks 1-5) using a three-dimensional conformal radiation therapy or intensity-modulated radiation therapy technique together with weekly docetaxel (20 mg/m(2) at dose levels 1 and 2, 25 mg/m(2) at dose level 3 on Weeks 1-5) and cisplatin (30 mg/m(2) at dose level 1, 40 mg/m(2) at dose levels 2 and 3 on Weeks 1-5) from January 2009 to December 2011. The dose-limiting toxicities and maximum tolerated dose were the primary endpoints and overall response rate and progression-free survival were the secondary endpoints. Over this timeframe, a total of 49 patients completed trimodality therapy. Thirteen patients were treated at dose level 1, 21 patients at dose level 2 and 15 patients at dose level 3.The maximum tolerated dose for docetaxel was 20 mg/m(2) and cisplatin 40 mg/m(2). The complete response or partial response was observed in 26.5% (13/49) of patients. Thirty-four patients (69.4%) were treated with neoadjuvant radiochemotherapy followed by surgical resection. The median progression-free survival and median overall survival for all patients (n = 49) were 8 and 17.2 months, respectively. The median overall survival was 27.5 months for patients treated at dose level 2. Neoadjuvant radiochemotherapy with docetaxel 20 mg/m(2) and cisplatin 40 mg/m(2) was effective and tolerable induction regimen in patients with esophageal tumors. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

High-Dose-Rate Brachytherapy for Non-Small-Cell Lung Carcinoma: A Retrospective Study of 226 Patients

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aumont-le Guilcher, Maud; Prevost, Bernard; Sunyach, Marie Pierre

Purpose: To evaluate the efficacy and toxicity of high-dose-rate (HDR) brachytherapy in patients with inoperable endobronchial carcinoma. Methods and Materials: We retrospectively reviewed the records (April 1991-May 2004) of patients with non-small-cell carcinoma, with no extrabronchial spread on computed tomography scans, who underwent HDR brachytherapy because of contraindications to surgery and external beam radiation therapy. Kaplan-Meier survival curves were compared by the log-rank test. Prognostic factors were analyzed by multivariate analysis. Results: 226 patients (223 men, 3 women, mean age: 62.2 years (range, 40-84)) were included. Of those, 217 (97%) had squamous cell carcinoma (Tis/T1/T2/Tx: 60/153/9/4). Dose was prescribed atmore » 1 cm from the radius (24-35 Gy in 4-6 fractions). Mean follow-up was 30.4 months (range, 9-116). Complete endoscopic response rate was 93.6% at 3 months. One hundred twenty-eight patients (56%) died of intercurrent disease (n = 45), local failure (n = 36), metastasis (n = 10), local failure and metastasis (n = 11), complications (n = 13), and other causes (n = 12). The 2-year and 5-year survival rates were, respectively, 57% and 29% (overall) (median, 28.6 months), 81% and 56% (cancer-specific), and 68% and 50% (local disease-free). Acute toxicity included pneumothorax (1.5%) and mucosal inflammation (10%). Late complications were hemoptysis (6.6% with 5% of fatalities), bronchitis (19.5%), and necrosis (3.5%). In multivariate analysis, a distal tumor location and the use of two catheters were associated with improved local disease-free survival (p = 0.003 and p = 0.007, respectively) and a distal tumor location with improved overall survival (p = 0.0001). Conclusions: This large retrospective study confirms that HDR brachytherapy is an efficient and safe treatment in patients with inoperable endobronchial carcinoma.« less

Single-hit mechanism of tumour cell killing by radiation.

PubMed

Chapman, J D

2003-02-01

To review the relative importance of the single-hit mechanism of radiation killing for tumour response to 1.8-2.0 Gy day(-1) fractions and to low dose-rate brachytherapy. Tumour cell killing by ionizing radiation is well described by the linear-quadratic equation that contains two independent components distinguished by dose kinetics. Analyses of tumour cell survival curves that contain six or more dose points usually provide good estimates of the alpha- and beta-inactivation coefficients. Superior estimates of tumour cell intrinsic radiosensitivity are obtained when synchronized populations are employed. The characteristics of single-hit inactivation of tumour cells are reviewed and compared with the characteristics of beta-inactivation. Potential molecular targets associated with single-hit inactivation are discussed along with strategies for potentiating cell killing by this mechanism. The single-hit mechanism of tumour cell killing shows no dependence on dose-rate and, consequently, no evidence of sublethal damage repair. It is uniquely potentiated by high linear-energy-transfer radiation, exhibits a smaller oxygen enhancement ratio and exhibits a larger indirect effect by hydroxyl radicals than the beta-mechanism. alpha-inactivation coefficients vary slightly throughout interphase but mitotic cells exhibit extremely high alpha-coefficients in the range of those observed for lymphocytes and some repair-deficient cells. Evidence is accumulating to suggest that chromatin in compacted form could be a radiation-hypersensitive target associated with single-hit radiation killing. Analyses of tumour cell survival curves demonstrate that it is the single-hit mechanism (alpha) that determines the majority of cell killing after doses of 2Gy and that this mechanism is highly variable between tumour cell lines. The characteristics of single-hit inactivation are qualitatively and quantitatively distinct from those of beta-inactivation. Compacted chromatin in tumour cells should be further investigated as a radiation-hypersensitive target that could be modulated for therapeutic advantage.

Impact of environmental factors on the culturability and viability of Listeria monocytogenes under conditions encountered in food processing plants.

PubMed

Overney, Anaïs; Jacques-André-Coquin, Joséphine; Ng, Patricia; Carpentier, Brigitte; Guillier, Laurent; Firmesse, Olivier

2017-03-06

The ability of Listeria monocytogenes to adhere to and persist on surfaces for months or even years may be responsible for its transmission from contaminated surfaces to food products. Hence the necessity to find effective means to prevent the establishment of L. monocytogenes in food processing environments. The aim of this study was to assess, through a fractional experimental design, the environmental factors that could affect the survival of L. monocytogenes cells on surfaces to thereby prevent the persistence of this pathogen in conditions mimicking those encountered in food processing plants: culture with smoked salmon juice or meat exudate, use of two materials with different hygiene status, biofilm of L. monocytogenes in pure-culture or dual-culture with a Pseudomonas fluorescens strain, application of a drying step after cleaning and disinfection (C&D) and comparison of two strains of L. monocytogenes. Bacterial survival was assessed by culture, qPCR to quantify total cells, and propidium monoazide coupled with qPCR to quantify viable cells and highlight viable but non-culturable (VBNC) cells. Our results showed that failure to apply C&D causes cell persistence on surfaces. Moreover, the sanitation procedure leads only to a loss of culturability and appearance of VBNC populations. However, an additional daily drying step after C&D optimises the effectiveness of these procedures to reduce culturable populations. Our results reinforce the importance to use molecular tools to monitor viable pathogens in food processing plants to avoid underestimating the amounts of cells using only methods based on cell culture. Copyright © 2017 Elsevier B.V. All rights reserved.

Targeting survival pathways in chronic myeloid leukaemia stem cells

PubMed Central

Sinclair, A; Latif, A L; Holyoake, T L

2013-01-01

Chronic myeloid leukaemia (CML) is a clonal myeloproliferative disorder characterized by the presence of a fusion oncogene BCR-ABL, which encodes a protein with constitutive TK activity. The implementation of tyrosine kinase inhibitors (TKIs) marked a major advance in CML therapy; however, there are problems with current treatment. For example, relapse occurs when these drugs are discontinued in the majority of patients who have achieved a complete molecular response on TKI and these agents are less effective in patients with mutations in the BCR-ABL kinase domain. Importantly, TKI can effectively target proliferating mature cells, but do not eradicate quiescent leukaemic stem cells (LSCs), therefore allowing disease persistence despite treatment. It is essential that alternative strategies are used to target the LSC population. BCR-ABL activation is responsible for the modulation of different signalling pathways, which allows the LSC fraction to evade cell death. Several pathways have been shown to be modulated by BCR-ABL, including PI3K/AKT/mTOR, JAK-STAT and autophagy signalling pathways. Targeting components of these survival pathways, alone or in combination with TKI, therefore represents an attractive potential therapeutic approach for targeting the LSC. However, many pathways are also active in normal stem cells. Therefore, potential targets must be validated to effectively eradicate CML stem cells while sparing normal counterparts. This review summarizes the main pathways modulated in CML stem cells, the recent developments and the use of novel drugs to target components in these pathways which may be used to target the LSC population. Linked Articles This article is part of a themed section on Emerging Therapeutic Aspects in Oncology. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2013.169.issue-8 PMID:23517124

Radiotherapeutic management of medulloblastoma in a pediatric patient with ataxia telangiectasia

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hart, R.M.; Kimler, B.F.; Evans, R.G.

1987-08-01

Ataxia telangiectasia (AT) is a genetic disorder with a predisposition to malignancy. Cells from patients with AT demonstrate an increased sensitivity to ionizing radiation which creates a problem when these patients require treatment for their malignant disease. An eleven-year-old boy with a previous diagnosis of AT was seen in consultation following partial resection of medulloblastoma in the posterior fossa. To estimate how much the conventional radiation dose might have to be reduced, we compared the radiosensitivity of bone marrow myeloid progenitor cells from this patient to that of cells from the marrow of normal individuals, using colony formation in anmore » agar culture assay system as the endpoint (CFU-Cs). Neither radiation dose-survival curve exhibited a shoulder--each displayed an extrapolation number of 0.99. The survival curve of normal cells displayed a steep slope with a D0 of 0.98 Gy (0.83-1.19 Gy, 95% confidence limits); the slope for the AT cells was considerably steeper with a value for D0 of 0.32 Gy (0.29-0.35 Gy). The ratio of D0's indicated that these AT cells were approximately 3X more radiosensitive than normal cells. Based on this, the daily dose was reduced from 1.8 to 0.6 Gy and the radiation was restricted to 25 treatments to the posterior fossa rather than the conventional cranio-spinal treatment. An additional 5 treatments at 1.0 Gy per day were given to the whole brain. The patient's skin responded to these reduced fraction sizes and doses to a similar degree as normal patients' skin following a standard schedule and the patient is doing well nine months after initiation of treatment.« less

Radio-sensitization by Piper longumine of human breast adenoma MDA-MB-231 cells in vitro.

PubMed

Yao, Jian-Xin; Yao, Zhi-Feng; Li, Zhan-Feng; Liu, Yong-Biao

2014-01-01

The current study investigated the effects of Piper longumine on radio-sensitization of human breast cancer MDA-MB-231 cells and underlying mechanisms. Human breast cancer MDA-MB-231 cells were cultured in vitro and those in logarithmic growth phase were selected for experiments divided into four groups: control, X-ray exposed, Piper longumine, and Piper longumine combined with X-rays. Conogenic assays were performed to determine the radio-sensitizing effects. Cell survival curves were fitted by single-hit multi-target model and then the survival fraction (SF), average lethal dose (D0), quasi-threshold dose (Dq) and sensitive enhancement ratio (SER) were calculated. Cell apoptosis was analyzed by flow cytometry (FCM).Western blot assays were employed for expression of apoptosis-related proteins (Bc1-2 and Bax) after treatment with Piper longumine and/or X-ray radiation. The intracellular reactive oxygen species (ROS) level was detected by FCM with a DCFH-DA probe. The cloning formation capacity was decreased in the group of piperlongumine plus radiation, which displayed the values of SF2, D0, Dq significantly lower than those of radiation alone group and the sensitive enhancement ratio (SER) of D0 was1.22 and 1.29, respectively. The cell apoptosis rate was increased by the combination treatment of Piper longumine and radiation. Piper longumine increased the radiation-induced intracellular levels of ROS. Compared with the control group and individual group, the combination group demonstrated significantly decreased expression of Bcl-2 with increased Bax. Piper longumine at a non-cytotoxic concentration can enhance the radio-sensitivity of MDA- MB-231cells, which may be related to its regulation of apoptosis-related protein expression and the increase of intracellular ROS level, thus increasing radiation-induced apoptosis.

Gamma-delta t-cell lymphomas.

PubMed

Foppoli, Marco; Ferreri, Andrés J M

2015-03-01

Gamma-delta T-cell lymphomas are aggressive and rare diseases originating from gamma-delta lymphocytes. These cells, which naturally play a role in the innate, non-specific immune response, develop from thymic precursor in the bone marrow, lack the major histocompatibility complex restrictions and can be divided into two subpopulations: Vdelta1, mostly represented in the intestine, and Vdelta2, prevalently located in the skin, tonsils and lymph nodes. Chronic immunosuppression such as in solid organ transplanted subjects and prolonged antigenic exposure are probably the strongest risk factors for the triggering of lymphomagenesis. Two entities are recognised by the 2008 WHO Classification: hepatosplenic gamma-delta T-cell lymphoma (HSGDTL) and primary cutaneous gamma-delta T-cell lymphoma (PCGDTL). The former is more common among young males, presenting with B symptoms, splenomegaly and thrombocytopenia, usually with the absence of nodal involvement. Natural behaviour of HSGDTL is characterised by low response rates, poor treatment tolerability, common early progression of disease and disappointing survival figures. PCGDTL accounts for <1% of all primary cutaneous lymphomas, occurring in adults with relevant comorbidities. Cutaneous lesions may vary, but its clinical behaviour is usually aggressive and long-term survival is anecdotal. Available literature on gamma-delta T-cell lymphomas is fractioned, mostly consisting of case reports or small cumulative series. Therefore, clinical suspicion and diagnosis are usually delayed, and therapeutic management remains to be established. This review critically analyses available evidence on diagnosis, staging and behaviour of gamma-delta T-cell lymphomas, provides recommendations for therapeutic management in routine practice and discusses relevant unmet clinical needs for future studies. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

NF-κB is not directly responsible for photoresistance induced by fractionated light delivery in HT-29 colon adenocarcinoma cells.

PubMed

Kuliková, Lucia; Mikeš, Jaromír; Hýžďalová, Martina; Palumbo, Giuseppe; Fedoročko, Peter

2010-01-01

Our recent study follows up an earlier one which demonstrated hypericin-mediated photocytotoxic effects on HT-29 adenocarcinoma cells by light fractionation with a longer dark pause between two unequal light doses (Sackova, A. [2005] Photochem. Photobiol.81, 1411-1416). Here, we present closer study on events invoked by sublethal light dose (1 J cm(-2)) during the period of 6 h that is sufficient to invoke resistance to second lethal dose (11 J cm(-2)). First, we proved that the dark pause of 6 h, but not 1 h, resulted in better cell survival with suppressed phosphatidylserine externalization, decreased reactive oxygen species production and hypericin content as well as altered expression of HSP70, GRP94, clusterin, nuclear factor (NF)-κB, IκB-α or Mcl-1. NF-κB activity assay confirmed activation of this early-response pathway. However, inhibition of IκB (IKK) kinase by parthenolide by stopping NF-κB release from the complex with IκB did not prevent onset of resistance, but it invoked some resistance even in groups with shorter, 1 h dark pause. Therefore, we predict involvement of another signaling pathway, located upstream from NF-κB, responsible for onset of resistance to photodynamic therapy with hypericin in colon adenocarcinoma cells HT-29. © 2010 The Authors. Journal Compilation. The American Society of Photobiology.

Hypofractionated radiosurgery for intact or resected brain metastases: defining the optimal dose and fractionation.

PubMed

Eaton, Bree R; Gebhardt, Brian; Prabhu, Roshan; Shu, Hui-Kuo; Curran, Walter J; Crocker, Ian

2013-06-07

Hypofractionated Radiosurgery (HR) is a therapeutic option for delivering partial brain radiotherapy (RT) to large brain metastases or resection cavities otherwise not amenable to single fraction radiosurgery (SRS). The use, safety and efficacy of HR for brain metastases is not well characterized and the optimal RT dose-fractionation schedule is undefined. Forty-two patients treated with HR in 3-5 fractions for 20 (48%) intact and 22 (52%) resected brain metastases with a median maximum dimension of 3.9 cm (0.8-6.4 cm) between May 2008 and August 2011 were reviewed. Twenty-two patients (52%) had received prior radiation therapy. Local (LC), intracranial progression free survival (PFS) and overall survival (OS) are reported and analyzed for relationship to multiple RT variables through Cox-regression analysis. The most common dose-fractionation schedules were 21 Gy in 3 fractions (67%), 24 Gy in 4 fractions (14%) and 30 Gy in 5 fractions (12%). After a median follow-up time of 15 months (range 2-41), local failure occurred in 13 patients (29%) and was a first site of failure in 6 patients (14%). Kaplan-Meier estimates of 1 year LC, intracranial PFS, and OS are: 61% (95% CI 0.53 - 0.70), 55% (95% CI 0.47 - 0.63), and 73% (95% CI 0.65 - 0.79), respectively. Local tumor control was negatively associated with PTV volume (p = 0.007) and was a significant predictor of OS (HR 0.57, 95% CI 0.33 - 0.98, p = 0.04). Symptomatic radiation necrosis occurred in 3 patients (7%). HR is well tolerated in both new and recurrent, previously irradiated intact or resected brain metastases. Local control is negatively associated with PTV volume and a significant predictor of overall survival, suggesting a need for dose escalation when using HR for large intracranial lesions.

In vitro expansion of Lin{sup +} and Lin{sup −} mononuclear cells from human peripheral blood

DOE Office of Scientific and Technical Information (OSTI.GOV)

Norhaiza, H. Siti; Zarina, Z. A. Intan; Hisham, Z. A. Shahrul

2013-11-27

Haematopoietic stem cells (HSCs) are used in the therapy of blood disorders due to the ability of these cells to reconstitute haematopoietic lineage cells when transplanted into myeloablative recipients. However, substantial number of cells is required in order for the reconstitution to take place. Since HSCs present in low frequency, larger number of donor is required to accommodate the demand of transplantable HSCs. Therefore, in vitro expansion of HSCs will have profound impact on clinical purposes. The aim of this study was to expand lineage negative (Lin{sup −}) stem cells from human peripheral blood. Total peripheral blood mononuclear cells (PBMNCs)more » were fractionated from human blood by density gradient centrifugation. Subsequently, PBMNCs were subjected to magnetic assisted cell sorter (MACS) which depletes lineage positive (Lin{sup +}) mononuclear cells expressing lineage positive markers such as CD2, CD3, CD11b, CD14, CD15, CD16, CD19, CD56, CD123, and CD235a to obtained Lin{sup −} cell population. The ability of Lin{sup +} and Lin{sup −} to survive in vitro was explored by culturing both cell populations in complete medium consisting of Alpha-Minimal Essential Medium (AMEM) +10% (v/v) Newborn Calf Serum (NBCS)+ 2% (v/v) pen/strep. In another experiment, Lin{sup +} and Lin{sup −} were cultured with complete medium supplemented with 10ng/mL of the following growth factors: stem cell factor (SCF), interleukin (IL)-3, granulocyte-macrophage colony stimulating factor (GM-CSF), 2IU/mL of Erythropoietin (Epo) and 20ng/mL of IL-6. Three samples were monitored in static culture for 22 days. The expansion potential was assessed by the number of total viable cells, counted by trypan blue exclusion assay. It was found that Lin{sup +} mononuclear cells were not able to survive either in normal proliferation medium or proliferation medium supplemented with cytokines. Similarly, Lin{sup −} stem cells were not able to survive in proliferation medium however, addition of cytokines into the proliferation medium support Lin{sup −} stem cells for at least 18 days. The Lin{sup −} stem cells started to response to the cytokines added as early as Day 2 of culture. It is concluded that Lin{sup −} stem cells can be expanded in vitro by culturing in proliferation medium supplemented with cytokines.« less

INDUCTION OF CELL CYCLE ARREST AND APOPTOSIS BY ORMENIS ERIOLEPIS A MORROCAN ENDEMIC PLANT IN VARIOUS HUMAN CANCER CELL LINES.

PubMed

Belayachi, Lamiae; Aceves-Luquero, Clara; Merghoub, Nawel; de Mattos, Silvia Fernández; Amzazi, Saaîd; Villalonga, Priam; Bakri, Youssef

2017-01-01

Ormenis eriolepis Coss (Asteraceae) is an endemic Moroccan subspecies, traditionally named "Hellala" or "Fergoga". It's usually used for its hypoglycemic effect as well as for the treatment of stomacal pain. As far as we know, there is no scientific exploration of anti tumoral activity of Ormenis eriolepis extracts. In this regard, we performed a screening of organic extracts and fractions in a panel of both hematological and solid cancer cell lines, to evaluate the potential in vitro anti tumoral activity and to elucidate the respective mechanisms that may be responsible for growth arrest and cell death induction. The plant was extracted using organic solvents, and four different extracts were screened on Jurkat, Jeko-1, TK-6, LN229, SW620, U2OS, PC-3 and NIH3T3 cells. Cell viability assays revealed that, the IC50 values were (11,63±5,37μg/ml) for Jurkat, (13,33±1,67μg/ml) for Jeko-1, (41,67±1,98μg/ml) for LN229 and (19,31±4,88μg/ml) for PC-3 cells upon treatment with Oe-DF and Oe-HE respectively. Both the fraction and extract exhibited no effects on TK6 and NIH3T3. Cytometry analysis accompanied by DNA damage signaling protein levels monitoring (p-H2A.X), showed that both the Dichloromethane Fraction and Hexanic extract induce DNA double stranded breaks (DSBs) accompanied by cell cycle arrest in G1 (Jurkat, Jeko -1 and LN22) and G2/M (PC-3) phases which is agreed with the caspase activity observed. Additional experiments with selective inhibitors of stress and survival pathways (JNK, MAPK, Rho, p53, and JAK3) indicated that none of these pathways was significantly involved in apoptosis induction. The bioactive compound analysis by CG/MS indicated that the major compounds in Oe-DF were: Linoleic Acid (15,89%), Podophyllotoxin (17,89%) and Quercetin (22,95%). For Oe-HE the major molecules were: Linoleic Acid (9,76%), α-curcumene (7,07%), α-bisabolol (5,49%), Campesterol (4,41%), Stigmasterol (14,08%) and β-sitosterol (7,49%). Our data suggest that bioactive compounds present in Ormenis eriolepis show significant anti proliferative activity inducing cell cycle arrest and cell death operating through apoptosis pathway.

Induction of apoptosis in melanoma A375 cells by a chloroform fraction of Centratherum anthelminticum (L.) seeds involves NF-kappaB, p53 and Bcl-2-controlled mitochondrial signaling pathways.

PubMed

Looi, Chung Yeng; Moharram, Bushra; Paydar, Mohammadjavad; Wong, Yi Li; Leong, Kok Hoong; Mohamad, Khalit; Arya, Aditya; Wong, Won Fen; Mustafa, Mohd Rais

2013-07-10

Centratherum anthelminticum (L.) Kuntze (scientific synonyms: Vernonia anthelmintica; black cumin) is one of the ingredients of an Ayurvedic preparation, called "Kayakalp", commonly applied to treat skin disorders in India and Southeast Asia. Despite its well known anti-inflammatory property on skin diseases, the anti-cancer effect of C. anthelminticum seeds on skin cancer is less documented. The present study aims to investigate the anti-cancer effect of Centratherum anthelminticum (L.) seeds chloroform fraction (CACF) on human melanoma cells and to elucidate the molecular mechanism involved. A chloroform fraction was extracted from C. anthelminticum (CACF). Bioactive compounds of the CACF were analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Human melanoma cell line A375 was treated with CACF in vitro. Effects of CACF on growth inhibition, morphology, stress and survival of the cell were examined with MTT, high content screening (HSC) array scan and flow cytometry analyses. Involvement of intrinsic or extrinsic pathways in the CACF-induced A375 cell death mechanism was examined using a caspase luminescence assay. The results were further verified with different caspase inhibitors. In addition, Western blot analysis was performed to elucidate the changes in apoptosis-associated molecules. Finally, the effect of CACF on the NF-κB nuclear translocation ability was assayed. The MTT assay showed that CACF dose-dependently inhibited cell growth of A375, while exerted less cytotoxic effect on normal primary epithelial melanocytes. We demonstrated that CACF induced cell growth inhibition through apoptosis, as evidenced by cell shrinkage, increased annexin V staining and formation of membrane blebs. CACF treatment also resulted in higher reactive oxygen species (ROS) production and lower Bcl-2 expression, leading to decrease mitochondrial membrane potential (MMP). Disruption of the MMP facilitated the release of mitochondrial cytochrome c, which activates caspase-9 and downstream caspase-3/7, resulting in DNA fragmentation and up-regulation of p53 in melanoma cells. Moreover, CACF prevented TNF-α-induced NF-κB nuclear translocation, which further committed A375 cells toward apoptosis. Together, our findings suggest CACF as a potential therapeutic agent against human melanoma malignancy.

The involvement of mRNA processing factors TIA-1, TIAR, and PABP-1 during mammalian hibernation.

PubMed

Tessier, Shannon N; Audas, Timothy E; Wu, Cheng-Wei; Lee, Stephen; Storey, Kenneth B

2014-11-01

Mammalian hibernators survive low body temperatures, ischemia-reperfusion, and restricted nutritional resources via global reductions in energy-expensive cellular processes and selective increases in stress pathways. Consequently, studies that analyze hibernation uncover mechanisms which balance metabolism and support survival by enhancing stress tolerance. We hypothesized processing factors that influence messenger ribonucleic acid (mRNA) maturation and translation may play significant roles in hibernation. We characterized the amino acid sequences of three RNA processing proteins (T cell intracellular antigen 1 (TIA-1), TIA1-related (TIAR), and poly(A)-binding proteins (PABP-1)) from thirteen-lined ground squirrels (Ictidomys tridecemlineatus), which all displayed a high degree of sequence identity with other mammals. Alternate Tia-1 and TiaR gene variants were found in the liver with higher expression of isoform b versus a in both cases. The localization of RNA-binding proteins to subnuclear structures was assessed by immunohistochemistry and confirmed by subcellular fractionation; TIA-1 was identified as a major component of subnuclear structures with up to a sevenfold increase in relative protein levels in the nucleus during hibernation. By contrast, there was no significant difference in the relative protein levels of TIARa/TIARb in the nucleus, and a decrease was observed for TIAR isoforms in cytoplasmic fractions of torpid animals. Finally, we used solubility tests to analyze the formation of reversible aggregates that are associated with TIA-1/R function during stress; a shift towards the soluble fraction (TIA-1a, TIA-1b) was observed during hibernation suggesting enhanced protein aggregation was not present during torpor. The present study identifies novel posttranscriptional regulatory mechanisms that may play a role in reducing translational rates and/or mRNA processing under unfavorable environmental conditions.

STAT3 activation in pressure-overloaded feline myocardium: role for integrins and the tyrosine kinase BMX.

PubMed

Willey, Christopher D; Palanisamy, Arun P; Johnston, Rebecca K; Mani, Santhosh K; Shiraishi, Hirokazu; Tuxworth, William J; Zile, Michael R; Balasubramanian, Sundaravadivel; Kuppuswamy, Dhandapani

2008-06-27

Growth, survival and cytoskeletal rearrangement of cardiomyocytes are critical for cardiac hypertrophy. Signal transducer and activator of transcription-3 (STAT3) activation is an important cardioprotective factor associated with cardiac hypertrophy. Although STAT3 activation has been reported via signaling through Janus Kinase 2 (JAK2) in several cardiac models of hypertrophy, the importance of other nonreceptor tyrosine kinases (NTKs) has not been explored. Utilizing an in vivo feline right ventricular pressure-overload (RVPO) model of hypertrophy, we demonstrate that in 48 h pressure-overload (PO) myocardium, STAT3 becomes phosphorylated and redistributed to detergent-insoluble fractions with no accompanying JAK2 activation. PO also caused increased levels of phosphorylated STAT3 in both cytoplasmic and nuclear fractions. To investigate the role of other NTKs, we used our established in vitro cell culture model of hypertrophy where adult feline cardiomyocytes are embedded three-dimensionally (3D) in type-I collagen and stimulated with an integrin binding peptide containing an Arg-Gly-Asp (RGD) motif that we have previously shown to recapitulate the focal adhesion complex (FAC) formation of 48 h RVPO. RGD stimulation of adult cardiomyocytes in vitro caused both STAT3 redistribution and activation that were accompanied by the activation and redistribution of c-Src and the TEC family kinase, BMX, but not JAK2. However, infection with dominant negative c-Src adenovirus was unable to block RGD-stimulated changes on either STAT3 or BMX. Further analysis in vivo in 48 h PO myocardium showed the presence of both STAT3 and BMX in the detergent-insoluble fraction with their complex formation and phosphorylation. Therefore, these studies indicate a novel mechanism of BMX-mediated STAT3 activation within a PO model of cardiac hypertrophy that might contribute to cardiomyocyte growth and survival.

RNA-binding properties and RNA chaperone activity of human peroxiredoxin 1

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, Ji-Hee; Lee, Jeong-Mi; Lee, Hae Na

2012-09-07

Highlights: Black-Right-Pointing-Pointer hPrx1 has RNA-binding properties. Black-Right-Pointing-Pointer hPrx1 exhibits helix-destabilizing activity. Black-Right-Pointing-Pointer Cold stress increases hPrx1 level in the nuclear fraction. Black-Right-Pointing-Pointer hPrx1 enhances the viability of cells exposed to cold stress. -- Abstract: Human peroxiredoxin 1 (hPrx1), a member of the peroxiredoxin family, detoxifies peroxide substrates and has been implicated in numerous biological processes, including cell growth, proliferation, differentiation, apoptosis, and redox signaling. To date, Prx1 has not been implicated in RNA metabolism. Here, we investigated the ability of hPrx1 to bind RNA and act as an RNA chaperone. In vitro, hPrx1 bound to RNA and DNA, and unwoundmore » nucleic acid duplexes. hPrx1 also acted as a transcription anti-terminator in an assay using an Escherichia coli strain containing a stem-loop structure upstream of the chloramphenicol resistance gene. The overall cellular level of hPrx1 expression was not increased at low temperatures, but the nuclear level of hPrx1 was increased. In addition, hPrx1 overexpression enhanced the survival of cells exposed to cold stress, whereas hPrx1 knockdown significantly reduced cell survival under the same conditions. These findings suggest that hPrx1 may perform biological functions as a RNA-binding protein, which are distinctive from known functions of hPrx1 as a reactive oxygen species scavenger.« less

Survival analysis of patients with esophageal cancer using parametric cure model.

PubMed

Rasouli, Mahboube; Ghadimi, Mahmood Reza; Mahmoodi, Mahmood; Mohammad, Kazem; Zeraati, Hojjat; Hosseini, Mostafa

2011-01-01

Esophageal cancer is a major cause of mortality and morbidity in the Caspian littoral north-eastern part of Iran. The aim of this study was to calculate cure function as well as to identify the factors that are related to this function among patients with esophageal cancer in this geographical area. Three hundred fifty nine cases of esophageal cancer registered in the Babol cancer registry during the period of 1990 to 1991 (inclusive) were followed up for 15 years up to 2006. Parametric cure model was used to calculate cure fraction and investigate the factors responsible for probability of cure among patients. Sample of subjects encompassed 62.7% men and 37.3% women, with mean ages of diagnosis was 60.0 and 55.3 years, respectively. The median survival time reached about 9 months and estimated survival rates in 1, 3, and 5 years following diagnosis were 23%, 15% and 13%, respectively. Results show the family history affects the cured fraction independently of its effect on early outcome and has a significant effect on the probability of uncured. The average cure fraction was estimated to be 0.10. As the proportionality assumption of Cox model does not meet in certain circumstances, a parametric cure model can provide a better fit and a better description of survival related outcome.

Targeting CD44 with nanoparticles in head and neck squamous cell carcinoma: A novel therapeutic strategy against cancer stem cells

NASA Astrophysics Data System (ADS)

Thapa, Ranjeeta

Head and neck squamous cell carcinoma (HNSCC) is the sixth most common type of cancer worldwide and is associated with significant morbidity and mortality. Advances in multi-modality treatments have only minimally improved survival rates in the past several years. Recent attention has been focused on the hypothesis that cancer stem cells (CSCs) may be responsible for the failure of current treatments. In HNSCC, a CSC population is contained within the cell fraction that expresses high levels of CD44. CD44 is a cell surface glycoprotein and was the first CSC marker to be described in solid malignancies. in this study, hyaluronan conjugated, dextran-coated super paramagnetic iron-oxide nanoparticles (HA-DESPIONs) were used to target the CD44 population in CD44-overexpressed HNSCC cell lines for treatment by establishing the interaction of HA-DESPIONs with radiation and hyperthermia therapy. The first part of this dissertation studied the cytotoxic, radiosensitizing, and hyperthermic properties of the HA-DESPIONs using cell proliferation and clonogenic survival assays. Cells were grown, plated, treated with HA-DESPIONs, irradiated/exposed to local hyperthermia, and then analyzed for apoptosis. HA-DESPIONs proved to be relatively non-toxic and nonradiosensitizing. However, temperature-dependent cell survival reduction upon incubation with HA-DESPIONs was observed with evidence of apoptotic cell death. These results supported further development of an alternating magnetic field (AMF) approach to activate the HADESPIONs attached to CSCs. In the second part of the dissertation, an AMF generator was constructed and its heat generating effect was tested via kinetic and dose-dependent bulk heating experiments by exposing magnetic nanoparticles to AMF. For elimination of the CD44 population, cells were treated with HA-DESPIONs/DESPIONs, exposed to AMF, and processed for flow cytometrybased apoptosis analysis. Magnetic nanoparticles caused concentration-dependent bulk heating in response to AMF resulting in a significant temperature rise. Following exposure to AMF, DESPIONs were unable to induce targeted hyperthermia and hence had no effect on CD44 cell death in HNSCC cells. However, there was significant cell death in the CD44 population treated with HA-DESPIONs and exposed to AMF. This effect was observed only when the AMF was turned on. These results demonstrated that HA-DESPIONs caused targeted cell-death in CD44overexpressing cells. This may be a promising strategy to specifically target CSCs for the treatment of HNSCC.

Radiosensitivity of human ovarian carcinoma and melanoma cells to γ-rays and protons

PubMed Central

Keta, Otilija; Todorović, Danijela; Popović, Nataša; Korićanac, Lela; Cuttone, Giacomo; Petrović, Ivan

2014-01-01

Introduction Proton radiation offers physical advantages over conventional radiation. Radiosensitivity of human 59M ovarian cancer and HTB140 melanoma cells was investigated after exposure to γ-rays and protons. Material and methods Irradiations were performed in the middle of a 62 MeV therapeutic proton spread out Bragg peak with doses ranging from 2 to 16 Gy. The mean energy of protons was 34.88 ±2.15 MeV, corresponding to the linear energy transfer of 4.7 ±0.2 keV/µm. Irradiations with γ-rays were performed using the same doses. Viability, proliferation and survival were assessed 7 days after both types of irradiation while analyses of cell cycle and apoptosis were performed 48 h after irradiation. Results Results showed that γ-rays and protons reduced the number of viable cells for both cell lines, with stronger inactivation achieved after irradiation with protons. Surviving fractions for 59M were 0.91 ±0.01 for γ-rays and 0.81 ±0.01 for protons, while those for HTB140 cells were 0.93 ±0.01 for γ-rays and 0.86 ±0.01 for protons. Relative biological effectiveness of protons, being 2.47 ±0.22 for 59M and 2.08 ±0.36 for HTB140, indicated that protons provoked better cell elimination than γ-rays. After proton irradiation proliferation capacity of the two cell lines was slightly higher as compared to γ-rays. Proliferation was higher for 59M than for HTB140 cells after both types of irradiation. Induction of apoptosis and G2 arrest detected after proton irradiation were more prominent in 59M cells. Conclusions The obtained results suggest that protons exert better antitumour effects on ovarian carcinoma and melanoma cells than γ-rays. The dissimilar response of these cells to radiation is related to their different features. PMID:25097591

Comparison of Different Adult Stem Cell Types for Treatment of Myocardial Ischemia

PubMed Central

van der Bogt, Koen E.A.; Sheikh, Ahmad Y.; Schrepfer, Sonja; Hoyt, Grant; Cao, Feng; Ransohoff, Katie; Swijnenburg, Rutger-Jan; Pearl, Jeremy; Fischbein, Michael; Contag, Christopher H.; Robbins, Robert C.; Wu, Joseph C.

2013-01-01

Introduction A comparative analysis of the efficacy of different cell candidates for the treatment of heart disease remains to be described. This study is designed to evaluate the therapeutic efficacy of 4 cell types in a murine model of myocardial infarction. Methods Bone marrow mononuclear cells (MN), mesenchymal stem cells (MSC), skeletal myoblasts (SkMb) and fibroblasts (Fibro) were isolated from male L2G transgenic mice (FVB background) that constitutively express firefly luciferase (Fluc) and green fluorescence protein (GFP). Cells were characterized by flow cytometry, bioluminescence imaging (BLI), and luminometry. Female FVB mice (n=60) underwent LAD ligation and were randomized into 5 groups to intramyocardially receive one cell type (5 × 105) or PBS as control. Cell survival was measured in vivo by BLI and ex vivo by TaqMan PCR at week 6. Cardiac function was assessed by echocardiography and invasive hemodynamic measurements were made at week 6. Results Fluc expression correlated with the cell number in all groups (r2 >0.93). In vivo BLI revealed acute donor cell death of MSC, SkMb, and Fibro within 3 weeks after transplantation. By contrast, cardiac signals were still present after 6 weeks in the MN group, as confirmed by TaqMan PCR (P<0.01). Echocardiography showed significant preservation of fractional shortening in the MN group compared to controls (P<0.05). Measurements of left ventricular end-systolic/diastolic volumes revealed that the least amount of ventricular dilatation occurred in the MN group (P<0.05). Histology confirmed the presence of MN, although there was no evidence of transdifferentiation by donor MN into cardiomyocytes. Conclusion This is the first study to directly compare a variety of cell candidates for myocardial therapy. Compared to MSC, SkMB, and Fibro, our results suggest that MN cells exhibit a more favorable survival pattern, which translates into a more robust preservation of cardiac function. PMID:18824743

Single- versus Multifraction Stereotactic Body Radiation Therapy for Pancreatic Adenocarcinoma: Outcomes and Toxicity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pollom, Erqi L.; Alagappan, Muthuraman; Eyben, Rie von

2014-11-15

Purpose: We report updated outcomes of single- versus multifraction stereotactic body radiation therapy (SBRT) for unresectable pancreatic adenocarcinoma. Methods and Materials: We included 167 patients with unresectable pancreatic adenocarcinoma treated at our institution from 2002 to 2013, with 1-fraction (45.5% of patient) or 5-fraction (54.5% of patients) SBRT. The majority of patients (87.5%) received chemotherapy. Results: Median follow-up was 7.9 months (range: 0.1-63.6). The 6- and 12-month cumulative incidence rates (CIR) of local recurrence for patients treated with single-fraction SBRT were 5.3% (95% confidence interval [CI], 0.2%-10.4%) and 9.5% (95% CI, 2.7%-16.2%), respectively. The 6- and 12-month CIR with multifraction SBRTmore » were 3.4% (95% CI, 0.0-7.2%) and 11.7% (95% CI, 4.8%-18.6%), respectively. Median survival from diagnosis for all patients was 13.6 months (95% CI, 12.2-15.0 months). The 6- and 12- month survival rates from SBRT for the single-fraction group were 67.0% (95% CI, 57.2%-78.5%) and 30.8% (95% CI, 21.9%-43.6%), respectively. The 6- and 12- month survival rates for the multifraction group were 75.7% (95% CI, 67.2%-85.3%) and 34.9% (95% CI, 26.1%-46.8%), respectively. There were no differences in CIR or survival rates between the single- and multifraction groups. The 6- and 12-month cumulative incidence rates of gastrointestinal toxicity grade ≥3 were 8.1% (95% CI, 1.8%-14.4%) and 12.3% (95% CI, 4.7%-20.0%), respectively, in the single-fraction group, and both were 5.6% (95% CI, 0.8%-10.5%) in the multifraction group. There were significantly fewer instances of toxicity grade ≥2 with multifraction SBRT (P=.005). Local recurrence and toxicity grade ≥2 were independent predictors of worse survival. Conclusions: Multifraction SBRT for pancreatic cancer significantly reduces gastrointestinal toxicity without compromising local control.« less

A randomized study to compare sequential chemoradiotherapy with concurrent chemoradiotherapy for unresectable locally advanced esophageal cancer.

PubMed

Gupta, Arunima; Roy, Somnath; Majumdar, Anup; Hazra, Avijit; Mallik, Chandrani

2014-01-01

Chemotherapy combined with radiotherapy can improve outcome in locally advanced esophageal cancer. This study aimed to compare efficacy and toxicity between concurrent chemoradiotherapy (CCRT) and sequential chemoradiotherapy (SCRT) in unresectable, locally advanced, esophageal squamous cell carcinoma (ESSC). Forty-one patients with unresectable, locally advanced ESCC were randomized into two arms. In the CCRT arm (Arm A), 17 patients received 50.4 Gy at 1.8 Gy per fraction over 5.6 weeks along with concurrent cisplatin (75 mg m(-2) intravenously on day 1 and 5-fluorouracil (1000 mg m(-2) continuous intravenous infusion on days 1-4 starting on the first day of irradiation and given after 28 days. In the SCRT arm (Arm B), 20 patients received two cycles of chemotherapy, using the same schedule, followed by radiotherapy fractionated in a similar manner. The endpoints were tumor response, acute and late toxicities, and disease-free survival. With a median follow up of 12.5 months, the complete response rate was 82.4% in Arm A and 35% in Arm B (P = 0.003). Statistically significant differences in frequencies of acute skin toxicity (P = 0.016), gastrointestinal toxicity (P = 0.005) and late radiation pneumonitis (P = 0.002) were found, with greater in the CCRT arm. A modest but non-significant difference was observed in median time to recurrence among complete responders in the two arms (Arm A 13 months and Arm B 15.5 months, P = 0.167) and there was also no significant difference between the Kaplan Meier survival plots (P = 0.641) of disease-free survival. Compared to sequential chemoradiotherapy, concurrent chemoradiotherapy can significantly improve local control rate but with greater risk of adverse reactions.

Comparison of Re-irradiation Outcomes for Charged Particle Radiotherapy and Robotic Stereotactic Radiotherapy Using CyberKnife for Recurrent Head and Neck Cancers: A Multi-institutional Matched-cohort Analysis.

PubMed

Yamazaki, Hideya; Demizu, Yusuke; Okimoto, Tomoaki; Ogita, Mikio; Himei, Kengo; Nakamura, Satoaki; Suzuki, Gen; Yoshida, Ken; Kotsuma, Tadayuki; Yoshioka, Yasuo

2016-10-01

To compare survival outcomes for charged particle radiotherapy (CP) and stereotactic body radiotherapy using CyberKnife (CK) in patients who had undergone re-irradiation for head and neck cancers. We conducted a retrospective multi-institutional matched-cohort analysis on 25 patients treated with CP and 25 matched patients treated with CK according to three prognostic factors (nasopharyngeal cancer or not, interval between initial radiotherapy and re-irradiation, and planning target volume). CP was used more often to treat non-squamous cell cancer ((non-SCC): 52% vs. 0%) with a higher prescribed dose (median=57.6 Gy(RBE)/16 fractions) than CK (32 Gy/5 fractions). The local control rate (LC) for patients treated with CP was 71.2% at 1 year and that for patients treated with CK was 63.8% (p=0.24). The 1-year overall survival (OS) rates were 67.1% for CP and 36.3% for CK (p=0.0002), respectively. Non-SCC patients showed better OS rates at 1 year than SCC patients. In the SCC sub-group analysis, the 1-year LC, OS rates were 65%, 58.3% in the CP group and 64%, 36.3% in the CK group (p=0.81, p=0.02), respectively. A total of 16 patients (32%) experienced grade 3 or worse toxicities (24% in CK and 40% in CP, p=0.36), including six grade 5 toxicities. CP produced higher survival rates than CK, treated more non-SCC patients and used a higher prescribed dose. On the other hand, severe toxicities occurred in both groups, which, however, require further investigation. Copyright© 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

Stereotactic Ablative Radiation Therapy is Highly Safe and Effective for Elderly Patients With Early-stage Non-Small Cell Lung Cancer.

PubMed

Brooks, Eric D; Sun, Bing; Zhao, Lina; Komaki, Ritsuko; Liao, Zhonxing; Jeter, Melenda; Welsh, James W; O'Reilly, Michael S; Gomez, Daniel R; Hahn, Stephen M; Heymach, John V; Rice, David C; Chang, Joe Y

2017-07-15

To discern the effectiveness and toxicity of stereotactic ablative radiation therapy (SABR) in the elderly population (aged ≥75 years) and to consider how SABR outcomes compare with surgical outcomes historically reported in the elderly. A total of 772 patients with clinical early-stage I-II non-small cell lung cancer (NSCLC; stage T1-T3N0M0) underwent SABR (50 Gy in 4 fractions or 70 Gy in 10 fractions) from 2004 to 2014 at our center (n=442, aged <75 years; n=330, aged ≥75 years). The primary endpoints included overall survival (OS), time-to-progression, and grade ≥3 toxicity. The median follow-up time was approximately 55 months. Compared with patients aged <75 years, those aged ≥75 years had no difference in the time-to-progression (P=.419), lung cancer-specific survival (P=.275), or toxicity (P=.536). OS was the same between both age groups at 2 years of follow-up but diverged thereafter, with patients aged <75 years when treatment began having greater OS rates at 5 years. The median OS rates for patients aged ≥75 years were 86% at 1 year, 57.5% at 3 years, and 39.5% at 5 years. The median OS rates for patients aged <75 years were 87.3% at 1 year, 67.6% at 3 years, and 51.5% at 5 years. No patient aged ≥75 years experienced any grade 4 or 5 toxicity. The effectiveness of SABR was the same for the elderly as for the average-age population according to lung cancer-specific survival and time-to-progression. It also poses no increased toxicity. Compared with the historical outcomes with surgery in the elderly, SABR outcomes can be considered comparable for stage I-II disease but with less morbidity. Copyright © 2016 Elsevier Inc. All rights reserved.

The efficacy and safety of simultaneous integrated boost intensity-modulated radiation therapy for esophageal squamous cell carcinoma in Chinese population: A single institution experience.

PubMed

Xu, Yujin; Wang, Zhun; Liu, Guan; Zheng, Xiao; Wang, Yuezhen; Feng, Wei; Lai, Xiaojing; Zhou, Xia; Li, Pu; Ma, Honglian; Wang, Jin; Hu, Xiao; Chen, Ming

2016-10-01

To evaluate the clinical efficacy and toxicity of simultaneous integrated boost intensity-modulated radiotherapy (SIB-IMRT) in patients with esophageal squamous cell carcinoma (ESCC) in Chinese population. Patients with ESCC, who received SIB-IMRT from September 2011 to January 2013 were retrospectively analyzed. The SIB-IMRT plans were designed to deliver primary gross tumor volume at 60-64.4 Gy in 28-30 fractions, and planning target volume at 50.4-56 Gy in 28-30 fractions. Treatment-related toxicities were estimated based on Common Terminology Criteria for Adverse Events version 4.0, and tumor response after the treatment was estimated according to Response Evaluation Criteria in Solid Tumors version 1.0. Overall survival (OS), locoregional progression-free survival (LPFS), and progression-free survival (PFS) were estimated with Kaplan-Meier. All patients completed definitive radiotherapy, 54 (78.3%) received combined chemotherapy, of which 31 (44.9%) were concurrent chemoradiotherapy and 23 (33.3%) were sequential chemotherapy. The objective response rate is 82.6% (56/69), with complete response 11 (15.9%), partial response 45 (65.2%), stable disease 8 (11.6%), and progressive disease 5 (7.2%). The 1-, 2- and 3-year LPFS was 74.4%, 57.8%, and 55.6%, respectively. The 1-, 2- and 3-year PFS was 62.3%, 41.0%, and 34.2%, respectively, and the 1-, 2-, and 3-year OS was 73.8%, 57.4%, and 41.0%, respectively, with a median OS of 27.1 months (4.5-54.9 m). For those who received concurrent chemotherapy, the 1-, 2-, and 3-year OS was 75.9%, 69.0%, and 55.2%, respectively, better than those who had sequential chemotherapy or radiotherapy alone (χ2 = 3.115, P = 0.078). Radiation esophagitis occurred in 63.8% and 14.5% with Grade 2 and 3, respectively. No patients occurred ≥ Grade 3 radiation pneumonia. It is safe and effective using SIB-IMRT technology to treat patients with ESCC. More prospective clinical studies should be needed.

Sequential CD34 cell fractionation by magnetophoresis in a magnetic dipole flow sorter.

PubMed

Schneider, Thomas; Karl, Stephan; Moore, Lee R; Chalmers, Jeffrey J; Williams, P Stephen; Zborowski, Maciej

2010-01-01

Cell separation and fractionation based on fluorescent and magnetic labeling procedures are common tools in contemporary research. These techniques rely on binding of fluorophores or magnetic particles conjugated to antibodies to target cells. Cell surface marker expression levels within cell populations vary with progression through the cell cycle. In an earlier work we showed the reproducible magnetic fractionation (single pass) of the Jurkat cell line based on the population distribution of CD45 surface marker expression. Here we present a study on magnetic fractionation of a stem and progenitor cell (SPC) population using the established acute myelogenous leukemia cell line KG-1a as a cell model. The cells express a CD34 cell surface marker associated with the hematopoietic progenitor cell activity and the progenitor cell lineage commitment. The CD34 expression level is approximately an order of magnitude lower than that of the CD45 marker, which required further improvements of the magnetic fractionation apparatus. The cells were immunomagnetically labeled using a sandwich of anti-CD34 antibody-phycoerythrin (PE) conjugate and anti-PE magnetic nanobead and fractionated into eight components using a continuous flow dipole magnetophoresis apparatus. The CD34 marker expression distribution between sorted fractions was measured by quantitative PE flow cytometry (using QuantiBRITE PE calibration beads), and it was shown to be correlated with the cell magnetophoretic mobility distribution. A flow outlet addressing scheme based on the concept of the transport lamina thickness was used to control cell distribution between the eight outlet ports. The fractional cell distributions showed good agreement with numerical simulations of the fractionation based on the cell magnetophoretic mobility distribution in the unsorted sample.

A voxel-based multiscale model to simulate the radiation response of hypoxic tumors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Espinoza, I., E-mail: iespinoza@fis.puc.cl; Peschke, P.; Karger, C. P.

2015-01-15

Purpose: In radiotherapy, it is important to predict the response of tumors to irradiation prior to the treatment. This is especially important for hypoxic tumors, which are known to be highly radioresistant. Mathematical modeling based on the dose distribution, biological parameters, and medical images may help to improve this prediction and to optimize the treatment plan. Methods: A voxel-based multiscale tumor response model for simulating the radiation response of hypoxic tumors was developed. It considers viable and dead tumor cells, capillary and normal cells, as well as the most relevant biological processes such as (i) proliferation of tumor cells, (ii)more » hypoxia-induced angiogenesis, (iii) spatial exchange of cells leading to tumor growth, (iv) oxygen-dependent cell survival after irradiation, (v) resorption of dead cells, and (vi) spatial exchange of cells leading to tumor shrinkage. Oxygenation is described on a microscopic scale using a previously published tumor oxygenation model, which calculates the oxygen distribution for each voxel using the vascular fraction as the most important input parameter. To demonstrate the capabilities of the model, the dependence of the oxygen distribution on tumor growth and radiation-induced shrinkage is investigated. In addition, the impact of three different reoxygenation processes is compared and tumor control probability (TCP) curves for a squamous cells carcinoma of the head and neck (HNSSC) are simulated under normoxic and hypoxic conditions. Results: The model describes the spatiotemporal behavior of the tumor on three different scales: (i) on the macroscopic scale, it describes tumor growth and shrinkage during radiation treatment, (ii) on a mesoscopic scale, it provides the cell density and vascular fraction for each voxel, and (iii) on the microscopic scale, the oxygen distribution may be obtained in terms of oxygen histograms. With increasing tumor size, the simulated tumors develop a hypoxic core. Within the model, tumor shrinkage was found to be significantly more important for reoxygenation than angiogenesis or decreased oxygen consumption due to an increased fraction of dead cells. In the studied HNSSC-case, the TCD{sub 50} values (dose at 50% TCP) decreased from 71.0 Gy under hypoxic to 53.6 Gy under the oxic condition. Conclusions: The results obtained with the developed multiscale model are in accordance with expectations based on radiobiological principles and clinical experience. As the model is voxel-based, radiological imaging methods may help to provide the required 3D-characterization of the tumor prior to irradiation. For clinical application, the model has to be further validated with experimental and clinical data. If this is achieved, the model may be used to optimize fractionation schedules and dose distributions for the treatment of hypoxic tumors.« less

Cure rate model with interval censored data.

PubMed

Kim, Yang-Jin; Jhun, Myoungshic

2008-01-15

In cancer trials, a significant fraction of patients can be cured, that is, the disease is completely eliminated, so that it never recurs. In general, treatments are developed to both increase the patients' chances of being cured and prolong the survival time among non-cured patients. A cure rate model represents a combination of cure fraction and survival model, and can be applied to many clinical studies over several types of cancer. In this article, the cure rate model is considered in the interval censored data composed of two time points, which include the event time of interest. Interval censored data commonly occur in the studies of diseases that often progress without symptoms, requiring clinical evaluation for detection (Encyclopedia of Biostatistics. Wiley: New York, 1998; 2090-2095). In our study, an approximate likelihood approach suggested by Goetghebeur and Ryan (Biometrics 2000; 56:1139-1144) is used to derive the likelihood in interval censored data. In addition, a frailty model is introduced to characterize the association between the cure fraction and survival model. In particular, the positive association between the cure fraction and the survival time is incorporated by imposing a common normal frailty effect. The EM algorithm is used to estimate parameters and a multiple imputation based on the profile likelihood is adopted for variance estimation. The approach is applied to the smoking cessation study in which the event of interest is a smoking relapse and several covariates including an intensive care treatment are evaluated to be effective for both the occurrence of relapse and the non-smoking duration. Copyright (c) 2007 John Wiley & Sons, Ltd.

Poor Prognosis Associated With Human Papillomavirus α7 Genotypes in Cervical Carcinoma Cannot Be Explained by Intrinsic Radiosensitivity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hall, John S.; Iype, Rohan; Armenoult, Lucile S.C.

2013-04-01

Purpose: To investigate the relationship between human papillomavirus (HPV) genotype and outcome after radiation therapy and intrinsic radiosensitivity. Methods and Materials: HPV genotyping was performed on cervix biopsies by polymerase chain reaction using SPF-10 broad-spectrum primers, followed by deoxyribonucleic acid enzyme immunoassay and genotyping by reverse hybridization line probe assay (LiPA{sub 25}) (version 1) (n=202). PapilloCheck and quantitative reverse transcription-polymerase chain reaction were used to genotype cervix cancer cell lines (n=16). Local progression-free survival after radiation therapy alone was assessed using log-rank and Cox proportionate hazard analyses. Intrinsic radiosensitivity was measured as surviving fraction at 2 Gy (SF2) using clonogenicmore » assays. Results: Of the 202 tumors, 107 (53.0%) were positive for HPV16, 29 (14.4%) for HPV18, 9 (4.5%) for HPV45, 23 (11.4%) for other HPV genotypes, and 22 (10.9%) were negative; 11 (5.5%) contained multiple genotypes, and 1 tumor was HPV X (0.5%). In 148 patients with outcome data, those with HPVα9-positive tumors had better local progression-free survival compared with α7 patients in univariate (P<.004) and multivariate (hazard ratio 1.54, 95% confidence interval 1.11-1.76, P=.021) analyses. There was no difference in the median SF2 of α9 and α7 cervical tumors (n=63). In the cell lines, 9 were α7 and 4 α9 positive and 3 negative. There was no difference in SF2 between α9 and α7 cell lines (n=14). Conclusion: The reduced radioresponsiveness of α7 cervical tumors is not related to intrinsic radiosensitivity.« less

Prospective Trial of Stereotactic Body Radiation Therapy for Both Operable and Inoperable T1N0M0 Non-Small Cell Lung Cancer: Japan Clinical Oncology Group Study JCOG0403

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nagata, Yasushi, E-mail: nagat@hiroshima-u.ac.jp; Hiraoka, Masahiro; Shibata, Taro

2015-12-01

Purpose: To evaluate, in Japan Clinical Oncology Group study 0403, the safety and efficacy of stereotactic body radiation therapy (SBRT) in patients with T1N0M0 non-small cell lung cancer (NSCLC). Methods and Materials: Eligibility criteria included histologically or cytologically proven NSCLC, clinical T1N0M0. Prescribed dose was 48 Gy at the isocenter in 4 fractions. The primary endpoint was the percent (%) 3-year overall survival. The threshold % 3-year survival to be rejected was set at 35% for inoperable patients, whereas the expected % 3-year survival was 80% for operable patients. Results: Between July 2004 and November 2008, 169 patients from 15 institutionsmore » were registered. One hundred inoperable and 64 operable patients (total 164) were eligible. Patients' characteristics were 122 male, 47 female; median age 78 years (range, 50-91 years); adenocarcinomas, 90; squamous cell carcinomas, 61; others, 18. Of the 100 inoperable patients, the % 3-year OS was 59.9% (95% confidence interval 49.6%-68.8%). Grade 3 and 4 toxicities were observed in 10 and 2 patients, respectively. No grade 5 toxicity was observed. Of the 64 operable patients, the % 3-year OS was 76.5% (95% confidence interval 64.0%-85.1%). Grade 3 toxicities were observed in 5 patients. No grade 4 and 5 toxicities were observed. Conclusions: Stereotactic body radiation therapy for stage I NSCLC is effective, with low incidences of severe toxicity. This treatment can be considered a standard treatment for inoperable stage I NSCLC. This treatment is promising as an alternative to surgery for operable stage I NSCLC.« less

Thoracic radiation therapy improves the overall survival of patients with extensive-stage small cell lung cancer with distant metastasis.

PubMed

Zhu, Hui; Zhou, Zongmei; Wang, Yan; Bi, Nan; Feng, Qinfu; Li, Junling; Lv, Jima; Chen, Dongfu; Shi, Yuankai; Wang, Luhua

2011-12-01

The authors conducted a retrospective study to evaluate the effects of thoracic radiation therapy (TRT) for patients with extensive-stage small cell lung cancer (ED-SCLC). Between January 2003 and December 2006, the records of 119 patients who were diagnosed with ED-SCLC (all with distant metastasis [M1]) were included in the study. Sixty patients received chemotherapy (ChT) and TRT (ChT/TRT), and 59 patients received ChT alone. The ChT regimens consisted of either carboplatin and etoposide (CE) or cisplatin and etoposide (PE). The total dose of TRT ranged from 40 to 60 grays (Gy) at 1.8 to 2.0 Gy per fraction. For the entire group, the median survival was 13 months, and the 2-year and 5-year overall survival (OS) rates were 26.1% and 6.5%, respectively. The median survival and the 2-year and 5-year OS rates were 17 months, 35%, and 7.1%, respectively, in the ChT/TRT group and 9.3 months, 17%, and 5.1%, respectively, in the ChT group (P = .014). However, this improvement was achieved at the expense of low toxicity. Multivariate analysis revealed that receiving ≥4 cycles of ChT (P = .032) and TRT (P = .005) were favorable prognostic factors for OS. Of all toxicities, only high-grade leucopenia (grade >3) was more frequent in the ChT/TRT group. The addition of TRT to ChT improved the OS of patients with ED-SCLC. Furthermore, receiving ≥4 cycles of ChT and TRT were independent, favorable prognostic factors for OS. Copyright © 2011 American Cancer Society.

Combined modality therapy for HIV-infected patients with squamous cell carcinoma of the anus: Outcomes and toxicities

DOE Office of Scientific and Technical Information (OSTI.GOV)

Edelman, Scott; Johnstone, Peter

Purpose: We report toxicity and survival data of human immunodeficiency virus (HIV)-infected men with anal carcinoma treated with combined modality therapy (CMT) of radiotherapy and concurrent chemotherapy. Methods and Materials: A retrospective review was performed on the records of 17 HIV-positive patients with anal squamous cell carcinoma treated with CMT at our institution between 1991 and 2004. Radiotherapy consisted of 30.6 to 45 Gy to the pelvis, total dose of 50.4 to 59.4 Gy to initial gross disease, at 1.8 Gy/fraction. Chemotherapy consisted of 5-fluorouracil and either mitomycin C or cisplatin. The mean follow-up was 25.6 months (median, 15.6 months;more » range, 4.6-106 months). Results: Significant acute skin and hematologic toxicity developed in 8 of 17 and 9 of 17 patients, respectively. One patient died 12 days after treatment of progressive disease and sepsis. Significant late toxic sequelae developed in 3 patients: 1 anorectal ulcer, 2 dermatologic (perianal ulceration, hemorrhagic perineal sores and suspected fissure). Fourteen of 15 patients with Stage I-III disease had a complete response; 2 complete responders subsequently had a relapse in the anorectum. For all patients, actuarial 18-month survival was 67%. For patients with Stage I-III disease, survival at last follow-up by low CD4 count (<200) vs. high count (>200) was 4 of 7 vs. 7 of 8, respectively; significant acute toxicities developed in 4 of 8 vs. 6 of 9, respectively. Conclusion: For HIV patients with anal carcinoma, CMT yields reasonable local control with significant acute complications. Survival is lower than in the general population, attributable more to the underlying infection than to the malignancy.« less

A phase III concurrent chemoradiotherapy trial with cisplatin and paclitaxel or docetaxel or gemcitabine in unresectable non-small cell lung cancer: KASLC 0401.

PubMed

Oh, In-Jae; Kim, Kyu-Sik; Kim, Young-Chul; Ban, Hee-Jung; Kwon, Yong-Soo; Kim, Yu-Il; Lim, Sung-Chul; Chung, Woong-Ki; Nam, Taek-Keun; Song, Joo-Young; Yoon, Mee-Sun; Ahn, Sung-Ja

2013-12-01

Concurrent chemoradiotherapy (CCRT) is recommended for the management of patients with unresectable non-small cell lung cancer (NSCLC). This prospective study aimed to compare the efficacy of concurrently delivered cisplatin doublets with paclitaxel, or docetaxel, or gemcitabine. The main eligibility criteria consisted of previously untreated stage IIIB NSCLC. The subjects were randomized into three arms: paclitaxel 45 mg/m(2)/week (TP), docetaxel 20 mg/m(2)/week (DP), and gemcitabine 350 mg/m(2)/week (GP) in addition to cisplatin 20 mg/m(2)/week. Three-dimensional conformal radiotherapy was given once daily, weekly 5 fractions and the total prescription dose was 60-66 Gy. The primary endpoint was response rate, and the secondary endpoints were survival and toxicity. A total of 101 patients were recruited into this trial of whom 93 (TP: 33, DP: 29, GP: 31) patients were treated with CCRT from March 2005 to July 2007. Similar response rates were observed across arms: TP: 63.6 %, DP: 72.4 %, GP: 61.3 % (p = 0.679). There was no statistically significant difference of median survival (TP: 27.3, DP: 27.6, GP: 16.5 months, p = 0.771). In subgroup analysis, a survival benefit of consolidation chemotherapy was not seen, but leucopenia (63.2 %) and neutropenia (68.4 %) more than grade 3 were significantly high in DP arm. The grade ≥3 radiation esophagitis was more frequent in the GP arm (22.6 %, p = 0.163). Among the three arms, no statistically significant difference in response rate, survival, and toxicity was observed. However, clinically significant radiation toxicity was more frequent in the GP arm.

Antiproliferative effects of yogurt fractions obtained by membrane dialysis on cultured mammalian intestinal cells.

PubMed

Ganjam, L S; Thornton, W H; Marshall, R T; MacDonald, R S

1997-10-01

The consumption of yogurt has been associated with a reduced incidence of colon cancer in population groups. Bioactive peptides produced during bacterial fermentation may alter the risk of colon cancer via modification of cell proliferation in the colon. Using our previously described cell culture model system, we have isolated a yogurt fraction that decreases cell proliferation. Yogurt was fractionated using 10,000- and 500-Da membrane dialysis. When the yogurt fraction was incubated with IEC-6 or Caco-2 cells, cell division was decreased compared with control treatments, as determined by thymidine incorporation. Cell division was not inhibited in response to a similarly produced milk fraction or in response to solutions of lactic acid. The determination of cell kinetics by flow cytometry revealed a decrease in the number of cells in the initial growth phase in response to the yogurt fraction for the IEC-6 cells, but not the Caco-2 cells. Alpha-Lactalbumin inhibited cell division of both cell lines, but beta-casein did not.

How many TCR clonotypes does a body maintain?

PubMed Central

Lythe, Grant; Callard, Robin E.; Hoare, Rollo L.; Molina-París, Carmen

2016-01-01

We consider the lifetime of a T cell clonotype, the set of T cells with the same T cell receptor, from its thymic origin to its extinction in a multiclonal repertoire. Using published estimates of total cell numbers and thymic production rates, we calculate the mean number of cells per TCR clonotype, and the total number of clonotypes, in mice and humans. When there is little peripheral division, as in a mouse, the number of cells per clonotype is small and governed by the number of cells with identical TCR that exit the thymus. In humans, peripheral division is important and a clonotype may survive for decades, during which it expands to comprise many cells. We therefore devise and analyse a computational model of homeostasis of a multiclonal population. Each T cell in the model competes for self pMHC stimuli, cells of any one clonotype only recognising a small fraction of the many subsets of stimuli. A constant mean total number of cells is maintained by a balance between cell division and death, and a stable number of clonotypes by a balance between thymic production of new clonotypes and extinction of existing ones. The number of distinct clonotypes in a human body may be smaller than the total number of naive T cells by only one order of magnitude. PMID:26546971

Elective nodal irradiation (ENI) in definitive chemoradiotherapy (CRT) for squamous cell carcinoma of the thoracic esophagus.

PubMed

Onozawa, Masakatsu; Nihei, Keiji; Ishikura, Satoshi; Minashi, Keiko; Yano, Tomonori; Muto, Manabu; Ohtsu, Atsushi; Ogino, Takashi

2009-08-01

There are some reports indicating that prophylactic three-field lymph node dissection for esophageal cancer can lead to improved survival. But the benefit of ENI in CRT for thoracic esophageal cancer remains controversial. The purpose of the present study is to retrospectively evaluate the efficacy of elective nodal irradiation (ENI) in definitive chemoradiotherapy (CRT) for thoracic esophageal cancer. Patients with squamous cell carcinoma (SCC) of the thoracic esophagus newly diagnosed between February 1999 and April 2001 in our institution was recruited from our database. Definitive chemoradiotherapy consisted of two cycles of cisplatin/5FU repeated every 5 weeks, with concurrent radiation therapy of 60 Gy in 30 fractions. Up to 40 Gy radiation therapy was delivered to the cervical, periesophageal, mediastinal and perigastric lymph nodes as ENI. One hundred two patients were included in this analysis, and their characteristics were as follows: median age, 65 years; male/female, 85/17; T1/T2/T3/T4, 16/11/61/14; N0/N1, 48/54; M0/M1, 84/18. The median follow-up period for the surviving patients was 41 months. Sixty patients achieved complete response (CR). After achieving CR, only one (1.0%; 95% CI, 0-5.3%) patient experienced elective nodal failure without any other site of recurrence. In CRT for esophageal SCC, ENI is effective for preventing regional nodal failure. Further evaluation of whether ENI leads to an improved overall survival is needed.

Nanoscale liposomal formulation of a SYK P-site inhibitor against B-precursor leukemia

PubMed Central

Qazi, Sanjive; Cely, Ingrid; Sahin, Kazim; Shahidzadeh, Anoush; Ozercan, Ibrahim; Yin, Qian; Gaynon, Paul; Termuhlen, Amanda; Cheng, Jianjun

2013-01-01

We report preclinical proof of principle for effective treatment of B-precursor acute lymphoblastic leukemia (ALL) by targeting the spleen tyrosine kinase (SYK)–dependent antiapoptotic blast cell survival machinery with a unique nanoscale pharmaceutical composition. This nanoscale liposomal formulation (NLF) contains the pentapeptide mimic 1,4-Bis (9-O dihydroquinidinyl) phthalazine/hydroquinidine 1,4-phathalazinediyl diether (C61) as the first and only selective inhibitor of the substrate binding P-site of SYK. The C61 NLF exhibited a very favorable pharmacokinetic and safety profile in mice, induced apoptosis in primary B-precursor ALL blast cells taken directly from patients as well as in vivo clonogenic ALL xenograft cells, destroyed the in vivo clonogenic fraction of ALL blast cells, and, at nontoxic dose levels, exhibited potent in vivo antileukemic activity against patient-derived ALL cells in xenograft models of aggressive B-precursor ALL. Our findings establish SYK as an attractive molecular target for therapy of B-precursor ALL. Further development of the C61 NLF may provide the foundation for therapeutic innovation against therapy-refractory B-precursor ALL. PMID:23568490

Resonant coherent excitation of 390 MeV/u Ar ions planar channeled in Si crystals

NASA Astrophysics Data System (ADS)

Komaki, K.; Azuma, T.; Ito, T.; Takabayashi, Y.; Yamazaki, Y.; Sano, M.; Torikoshi, M.; Kitagawa, A.; Takada, E.; Murakami, T.

1998-12-01

Resonant coherent excitation of the 1s electron to n=2 states in a hydrogen-like ion was studied through measurements of the survived fraction of 390 MeV/u Ar17+ planar channeled in a Si crystal. Adopting a totally depleted Si surface barrier detector as a target crystal, the charge state of the individual emerged ion was measured in coincidence with the energy deposition in the target. By changing the incident direction along the (2 overline2 0), (0 0 4), and (1 overline1 1) planes, a series of clear resonances were observed as the decrease in the survived charge fraction due to higher electron loss probability for the excited state. Each resonance profile reflects energy splitting of the n=2 manifold originated from l-s interaction and Stark effect due to the crystal field. From the correlation between the energy loss and survived charge fraction, transition energy as a function of the ion trajectory amplitude is deduced which is in good agreement with calculated results.

Quinolinic acid induces neuritogenesis in SH-SY5Y neuroblastoma cells independently of NMDA receptor activation.

PubMed

Hernandez-Martinez, Juan-Manuel; Forrest, Caroline M; Darlington, L Gail; Smith, Robert A; Stone, Trevor W

2017-03-01

Glutamate and nicotinamide adenine dinucleotide (NAD + ) have been implicated in neuronal development and several types of cancer. The kynurenine pathway of tryptophan metabolism includes quinolinic acid (QA) which is both a selective agonist at N-methyl-D-aspartate (NMDA) receptors and also a precursor for the formation of NAD + . The effect of QA on cell survival and differentiation has therefore been examined on SH-SY5Y human neuroblastoma cells. Retinoic acid (RA, 10 μm) induced differentiation of SH-SY5Y cells into a neuronal phenotype showing neurite growth. QA (50-150 nm) also caused a concentration-dependent increase in the neurite/soma ratio, indicating differentiation. Both RA and QA increased expression of the neuronal marker β3-tubulin in whole-cell homogenates and in the neuritic fraction assessed using a neurite outgrowth assay. Expression of the neuronal proliferation marker doublecortin revealed that, unlike RA, QA did not decrease the number of mitotic cells. QA-induced neuritogenesis coincided with an increase in the generation of reactive oxygen species. Neuritogenesis was prevented by diphenylene-iodonium (an inhibitor of NADPH oxidase) and superoxide dismutase, supporting the involvement of reactive oxygen species. NMDA itself did not promote neuritogenesis and the NMDA antagonist dizocilpine (MK-801) did not prevent quinolinate-induced neuritogenesis, indicating that the effects of QA were independent of NMDA receptors. Nicotinamide caused a significant increase in the neurite/soma ratio and the expression of β3-tubulin in the neuritic fraction. Taken together, these results suggest that QA induces neuritogenesis by promoting oxidizing conditions and affecting the availability of NAD + , independently of NMDA receptors. © 2016 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

Kidney cell electrophoresis, continuing task

NASA Technical Reports Server (NTRS)

Todd, P. W.

1985-01-01

Materials and procedures for microgravity electrophoresis of living human embryonic kidney cells were evaluated to provide ground support in the form of analytical cell electrophoresis and flow cytometry. Preflight culture media, electrophoresis buffer, fraction collection media, temperature profiles, and urokinase assay procedures were tested prior to flight. Electrophoretic mobility distributions of aliquots of the cell population to be fractionated in flight were obtained. Cells were prepared in suspension prior to flight in electrophoresis buffer and 10% calf serum. Electrophoretic separation proceeded in electrophoresis buffer without serum in the Continuous Flow Electrophoretic Separator, and fractions were collected into sample bags containing culture medium and concentrated serum. Fractions that yielded enough progeny cells were analyzed for morphology and electrophoretic mobility distributions. It is noted that the lowest mobility fraction studied produced higher mobility progeny while the other fractions produced progeny cells with mobilities related to the fractions from which they were collected.

A 2011 Updated Systematic Review and Clinical Practice Guideline for the Management of Malignant Extradural Spinal Cord Compression

DOE Office of Scientific and Technical Information (OSTI.GOV)

Loblaw, D. Andrew, E-mail: andrew.loblaw@sunnybrook.ca; Mitera, Gunita; Ford, Michael

2012-10-01

Purpose: To update the 2005 Cancer Care Ontario practice guidelines for the diagnosis and treatment of adult patients with a suspected or confirmed diagnosis of extradural malignant spinal cord compression (MESCC). Methods: A review and analysis of data published from January 2004 to May 2011. The systematic literature review included published randomized control trials (RCTs), systematic reviews, meta-analyses, and prospective/retrospective studies. Results: An RCT of radiation therapy (RT) with or without decompressive surgery showed improvements in pain, ambulatory ability, urinary continence, duration of continence, functional status, and overall survival. Two RCTs of RT (30 Gy in eight fractions vs. 16more » Gy in two fractions; 16 Gy in two fractions vs. 8 Gy in one fraction) in patients with a poor prognosis showed no difference in ambulation, duration of ambulation, bladder function, pain response, in-field failure, and overall survival. Retrospective multicenter studies reported that protracted RT schedules in nonsurgical patients with a good prognosis improved local control but had no effect on functional or survival outcomes. Conclusions: If not medically contraindicated, steroids are recommended for any patient with neurologic deficits suspected or confirmed to have MESCC. Surgery should be considered for patients with a good prognosis who are medically and surgically operable. RT should be given to nonsurgical patients. For those with a poor prognosis, a single fraction of 8 Gy should be given; for those with a good prognosis, 30 Gy in 10 fractions could be considered. Patients should be followed up clinically and/or radiographically to determine whether a local relapse develops. Salvage therapies should be introduced before significant neurologic deficits occur.« less

The use of spine stereotactic radiosurgery for oligometastatic disease.

PubMed

Ho, Jennifer C; Tang, Chad; Deegan, Brian J; Allen, Pamela K; Jonasch, Eric; Amini, Behrang; Wang, Xin A; Li, Jing; Tatsui, Claudio E; Rhines, Laurence D; Brown, Paul D; Ghia, Amol J

2016-08-01

OBJECTIVE The authors investigated the outcomes following spine stereotactic radiosurgery (SSRS) for patients with oligometastatic disease of the spine. METHODS The study was a secondary analysis of 38 of 209 patients enrolled in 2 separate institutional Phase I/II prospective protocols and treated with SSRS between 2002 and 2011. Of these 38 patients, 33 (87%) were treated for a solitary spine metastasis, with no other history of metastatic disease. SSRS was prescribed to 24 Gy in 1 fraction (8%), 18 Gy in 1 fraction (18%), 16 Gy in 1 fraction (11%), 27 Gy in 3 fractions (53%), 30 Gy in 5 fractions (8%), or 20 Gy in 5 fractions (3%). Seventeen patients (45%) received prior conventional external beam radiation therapy. RESULTS The median overall survival (OS) was 75.7 months, and the 2- and 5-year OS rates were 84% and 60%, respectively. In multivariate analysis, patients who had prior spine surgery and a better Karnofsky Performance Scale score had an improved OS (HR 0.16, 95% CI 0.05-0.52, p < 0.01, and HR 0.33, 95% CI 0.13%-0.84%, p = 0.02, respectively), and those who had undergone prior radiation therapy had a worse OS (HR 3.6, 95% CI 1.2%-10%, p = 0.02). The 1-, 2-, and 5-year local progression-free survival rates were 85%, 82%, and 78%, respectively. The median time to systemic therapy modification was 41 months. Two patients (5%) experienced late Grade 3-4 toxicity. CONCLUSIONS Patients with oligometastatic disease of the spine treated with SSRS can experience long-term survival and a long time before needing a modification in systemic therapy. In addition, SSRS leads to excellent local control and minimal late toxicity.

Three-year outcomes of a once daily fractionation scheme for accelerated partial breast irradiation (APBI) using 3-D conformal radiotherapy (3D-CRT)

PubMed Central

Goyal, Sharad; Daroui, Parima; Khan, Atif J; Kearney, Thomas; Kirstein, Laurie; Haffty, Bruce G

2013-01-01

The aim of this study was to report 3-year outcomes of toxicity, cosmesis, and local control using a once daily fractionation scheme (49.95 Gy in 3.33 Gy once daily fractions) for accelerated partial breast irradiation (APBI) using three-dimensional conformal radiotherapy (3D-CRT). Between July 2008 and August 2010, women aged ≥40 years with ductal carcinoma in situ or node-negative invasive breast cancer ≤3 cm in diameter, treated with breast-conserving surgery achieving negative margins, were accrued to a prospective study. Women were treated with APBI using 3–5 photon beams, delivering 49.95 Gy over 15 once daily fractions over 3 weeks. Patients were assessed for toxicities, cosmesis, and local control rates before APBI and at specified time points. Thirty-four patients (mean age 60 years) with Tis 0 (n = 9) and T1N0 (n = 25) breast cancer were treated and followed up for an average of 39 months. Only 3% (1/34) patients experienced a grade 3 subcutaneous fibrosis and breast edema and 97% of the patients had good/excellent cosmetic outcome at 3 years. The 3-year rate of ipsilateral breast tumor recurrence (IBTR) was 0% while the rate of contralateral breast events was 6%. The 3-year disease-free survival (DFS), overall survival (OS), and breast cancer-specific survival (BCSS) was 94%, 100%, and 100%, respectively. Our novel accelerated partial breast fractionation scheme of 15 once daily fractions of 3.33 Gy (49.95 Gy total) is a remarkably well-tolerated regimen of 3D-CRT-based APBI. A larger cohort of patients is needed to further ascertain the toxicity of this accelerated partial breast regimen. PMID:24403270

Effect of Midtreatment PET/CT-Adapted Radiation Therapy With Concurrent Chemotherapy in Patients With Locally Advanced Non–Small-Cell Lung Cancer

PubMed Central

Kong, Feng-Ming; Ten Haken, Randall K.; Schipper, Matthew; Frey, Kirk A.; Hayman, James; Gross, Milton; Ramnath, Nithya; Hassan, Khaled A.; Matuszak, Martha; Ritter, Timothy; Bi, Nan; Wang, Weili; Orringer, Mark; Cease, Kemp B.; Lawrence, Theodore S.; Kalemkerian, Gregory P.

2017-01-01

IMPORTANCE Our previous studies demonstrated that tumors significantly decrease in size and metabolic activity after delivery of 45 Gy of fractionated radiatiotherapy (RT), and that metabolic shrinkage is greater than anatomic shrinkage. This study aimed to determine whether 18F-fludeoxyglucose–positron emission tomography/computed tomography (FDG-PET/CT) acquired during the course of treatment provides an opportunity to deliver higher-dose radiation to the more aggressive areas of the tumor to improve local tumor control without increasing RT-induced lung toxicity (RILT), and possibly improve survival. OBJECTIVE To determine whether adaptive RT can target high-dose radiation to the FDG-avid tumor on midtreatment FDG-PET to improve local tumor control of locally advanced non–small-cell lung cancer (NSCLC). DESIGN, SETTING, AND PARTICIPANTS A phase 2 clinical trial conducted at 2 academic medical centers with 42 patients who had inoperable or unresectable stage II to stage III NSCLC enrolled from November 2008, to May 2012. Patients with poor performance, more than 10% weight loss, poor lung function, and/or oxygen dependence were included, providing that the patients could tolerate the procedures of PET scanning and RT. INTERVENTION Conformal RT was individualized to a fixed risk of RILT (grade >2) and adaptively escalated to the residual tumor defined on midtreatment FDG-PET up to a total dose of 86 Gy in 30 daily fractions. Medically fit patients received concurrent weekly carboplatin plus paclitaxel followed by 3 cycles of consolidation. MAIN OUTCOMES AND MEASURES The primary end point was local tumor control. The trial was designed to achieve a 20% improvement in 2-year control from 34% of our prior clinical trial experience with 63 to 69 Gy in a similar patient population. RESULTS The trial reached its accrual goal of 42 patients: median age, 63 years (range, 45–83 years); male, 28 (67%); smoker or former smoker, 39 (93%); stage III, 38 (90%). Median tumor dose delivered was 83 Gy (range, 63–86 Gy) in 30 daily fractions. Median follow-up for surviving patients was 47 months. The 2-year rates of infield and overall local regional tumor controls (ie, including isolated nodal failure) were 82% (95% CI, 62%–92%) and 62% (95% CI, 43%–77%), respectively. Median overall survival was 25 months (95% CI, 12–32 months). The 2-year and 5-year overall survival rates were 52% (95% CI, 36%–66%) and 30% (95% CI, 16%–45%), respectively. CONCLUSIONS AND RELEVANCE Adapting RT-escalated radiation dose to the FDG-avid tumor detected by midtreatment PET provided a favorable local-regional tumor control. The RTOG 1106 trial is an ongoing clinical trial to validate this finding in a randomized fashion. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT01190527 PMID:28570742

Detection of DNA damage in individual cells by flow cytometric analysis using anti-DNA monoclonal antibody

DOE Office of Scientific and Technical Information (OSTI.GOV)

Frankfurt, O.S.

A new method for the measurement of DNA damage in individual cells treated with alkylating agents is described. The method is based on the binding of anti-DNA monoclonal antibody to DNA in situ. Binding of antibody was evaluated by flow cytometry with indirect immunofluorescence. No binding of antibody to DNA in non-treated HeLa S3 cells was detected. Treatment of cells with HN2 or L-phenylalanine mustard induced binding of antibody to DNA in situ. Binding of antibody was observed after treating cells with doses of drugs which reduced the surviving fraction below 20%. Intensity of binding increased in proportion to themore » drug dose. In HN2-treated cells a cell subset with the lowest antibody binding was observed among cells in G1 phase. Binding of antibody to DNA in HN2-treated cells was eliminated by single-strand (ss) specific S1 nuclease. In competition assay, antibody was inhibited by thermally denatured DNA, but not by native double-stranded (ds) DNA, RNA, nucleosides and deoxyribohomopolymers. Immunoreactivity of cells with the monoclonal antibody F7-26 may be a useful probe for the assessment of cell damage induced by alkylating agents, especially in heterogeneous cell populations.« less

BCR-ABL enhances differentiation of long-term repopulating hematopoietic stem cells

PubMed Central

Schemionek, Mirle; Elling, Christian; Steidl, Ulrich; Bäumer, Nicole; Hamilton, Ashley; Spieker, Tilmann; Göthert, Joachim R.; Stehling, Martin; Wagers, Amy; Huettner, Claudia S.; Tenen, Daniel G.; Tickenbrock, Lara; Berdel, Wolfgang E.; Serve, Hubert; Holyoake, Tessa L.; Müller-Tidow, Carsten

2010-01-01

In a previously developed inducible transgenic mouse model of chronic myeloid leukemia, we now demonstrate that the disease is transplantable using BCR-ABL+ Lin−Sca-1+c-kit+ (LSK) cells. Interestingly, the phenotype is more severe when unfractionated bone marrow cells are transplanted, yet neither progenitor cells (Lin−Sca-1−c-kit+), nor mature granulocytes (CD11b+Gr-1+), nor potential stem cell niche cells (CD45−Ter119−) are able to transmit the disease or alter the phenotype. The phenotype is largely independent of BCR-ABL priming before transplantation. However, prolonged BCR-ABL expression abrogates the potential of LSK cells to induce full-blown disease in secondary recipients and increases the fraction of multipotent progenitor cells at the expense of long-term hematopoietic stem cells (LT-HSCs) in the bone marrow. BCR-ABL alters the expression of genes involved in proliferation, survival, and hematopoietic development, probably contributing to the reduced LT-HSC frequency within BCR-ABL+ LSK cells. Reversion of BCR-ABL, or treatment with imatinib, eradicates mature cells, whereas leukemic stem cells persist, giving rise to relapsed chronic myeloid leukemia on reinduction of BCR-ABL, or imatinib withdrawal. Our results suggest that BCR-ABL induces differentiation of LT-HSCs and decreases their self-renewal capacity. PMID:20053753

Cardiopulmonary resuscitation quality and patient survival outcome in cardiac arrest: A systematic review and meta-analysis.

PubMed

Talikowska, Milena; Tohira, Hideo; Finn, Judith

2015-11-01

To conduct a systematic review and meta-analysis to determine whether cardiopulmonary resuscitation (CPR) quality, as indicated by parameters such as chest compression depth, compression rate and compression fraction, is associated with patient survival from cardiac arrest. Five databases were searched (MEDLINE, Embase, CINAHL, Scopus and Cochrane) as well as the grey literature (MedNar). To satisfy inclusion criteria, studies had to document human cases of in- or out-of hospital cardiac arrest where CPR quality had been recorded using an automated device and linked to patient survival. Where indicated (I(2)<75%), meta-analysis was undertaken to examine the relationship between individual CPR quality parameters and either survival to hospital discharge (STHD) or return of spontaneous circulation (ROSC). Database searching yielded 8,842 unique citations, resulting in the inclusion of 22 relevant articles. Thirteen were included in the meta-analysis. Chest compression depth was significantly associated with STHD (mean difference (MD) between survivors and non-survivors 2.59 mm, 95% CI: 0.71, 4.47); and with ROSC (MD 0.99 mm, 95% CI: 0.04, 1.93). Within the range of approximately 100-120 compressions per minute (cpm), compression rate was significantly associated with STHD; survivors demonstrated a lower mean compression rate than non-survivors (MD -1.17 cpm, 95% CI: -2.21, -0.14). Compression fraction could not be examined by meta-analysis due to high heterogeneity, however a higher fraction appeared to be associated with survival in cases with a shockable initial rhythm. Chest compression depth and rate were associated with survival outcomes. More studies with consistent reporting of data are required for other quality parameters. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Survival fraction and phenotype alterations of Xenopus laevis embryos at 3 Gy, 150 kV X-ray irradiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Carotenuto, Rosa; Tussellino, Margherita; Mettivier, Giovanni

To determine the radiosensitivity of Xenopus laevis embryos, aquatic organism model, for toxicity studies utilizing X-rays at acute high dose levels, by analysing its survival fraction and phenotype alterations under one-exposure integral dose. We used the standard Frog Embryo Teratogenesis Assay Xenopus test during the early stages of X. laevis development. The embryos were harvested until st. 46 when they were irradiated. The radiation effects were checked daily for a week and the survival, malformations and growth inhibition were assessed. Sibling tadpoles as control organisms were used. Statistical analysis was performed to assess the extent of any damage. Irradiation was performedmore » with an X-ray tube operated at 150 kV. The tube containing the tadpoles was exposed to an air kerma of 3 Gy as measured in air with an in-beam ionization chamber. After one week, survival fraction of irradiated embryos was 58%, while for control embryos it was 81%. Hence, irradiation with 150 kV, 3 Gy X-rays produced a 23% decrease of survival in regard to unirradiated embryos. The 70% of the irradiated embryos showed an altered distribution of the skin pigmentation, in particular on the dorsal area and in the olfactory pits, where the pigment concentration increased by a factor 2. In conclusion exposure of X. laevis to 3 Gy, 150 kV X-rays induced a reduction of embryos survival and a significant modification of pigmentation. The authors think that X. laevis embryos, at st 46, is a suitable biological model for large scale investigations on the effects of ionizing radiation.« less

Survival and metabolic activity of the GanedenBC30 strain of Bacillus coagulans in a dynamic in vitro model of the stomach and small intestine.

PubMed

Maathuis, A J H; Keller, D; Farmer, S

2010-03-01

We have investigated the survival and activity of GanedenBC(30) during passage through the upper gastro-intestinal tract. GanedenBC(30) was tested in a dynamic, validated, in vitro model of the stomach and small intestine (TIM-1) on survival and its potential to aid in digestion of milk protein, lactose and fructose. The survival of GanedenBC(30) was high (70%), although germination of the spores was minimal (<10%) under the conditions tested. Survival of the strain in the presence of lactose and fructose was markedly lower (56-59%) than in the absence of the sugars. The amount of digested milk protein available for absorption was somewhat higher (+0.2 g) when GanedenBC(30) was added to the milk. When GanedenBC(30) was tested with lactose or fructose added to the meal, the cumulative amount of lactate produced was slightly higher (+0.12-0.18 mmol) compared to the GanedenBC(30) alone. In conclusion, although the differences in survival of GanedenBC(30) are small, these results show the potential of GanedenBC(30) to aid in protein digestion and in the digestion of lactose and fructose. If a larger fraction of the Bacillus coagulans cells had germinated, the influence on protein and carbohydrate digestion would probably have been much greater. Importance of the findings: the potential of GanedenBC(30) to aid in the digestion of lactose and fructose could be used to prevent occurrence of intestinal symptoms in individuals sensitive to these carbohydrates.

Mathematical modeling of erythrocyte chimerism informs genetic intervention strategies for sickle cell disease.

PubMed

Altrock, Philipp M; Brendel, Christian; Renella, Raffaele; Orkin, Stuart H; Williams, David A; Michor, Franziska

2016-09-01

Recent advances in gene therapy and genome-engineering technologies offer the opportunity to correct sickle cell disease (SCD), a heritable disorder caused by a point mutation in the β-globin gene. The developmental switch from fetal γ-globin to adult β-globin is governed in part by the transcription factor (TF) BCL11A. This TF has been proposed as a therapeutic target for reactivation of γ-globin and concomitant reduction of β-sickle globin. In this and other approaches, genetic alteration of a portion of the hematopoietic stem cell (HSC) compartment leads to a mixture of sickling and corrected red blood cells (RBCs) in periphery. To reverse the sickling phenotype, a certain proportion of corrected RBCs is necessary; the degree of HSC alteration required to achieve a desired fraction of corrected RBCs remains unknown. To address this issue, we developed a mathematical model describing aging and survival of sickle-susceptible and normal RBCs; the former can have a selective survival advantage leading to their overrepresentation. We identified the level of bone marrow chimerism required for successful stem cell-based gene therapies in SCD. Our findings were further informed using an experimental mouse model, where we transplanted mixtures of Berkeley SCD and normal murine bone marrow cells to establish chimeric grafts in murine hosts. Our integrative theoretical and experimental approach identifies the target frequency of HSC alterations required for effective treatment of sickling syndromes in humans. Our work replaces episodic observations of such target frequencies with a mathematical modeling framework that covers a large and continuous spectrum of chimerism conditions. Am. J. Hematol. 91:931-937, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Tumoricidal activity of low-energy 160-KV versus 6-MV X-rays against platinum-sensitized F98 glioma cells

PubMed Central

Lim, Sara N.; Pradhan, Anil K.; Barth, Rolf F.; Nahar, Sultana N.; Nakkula, Robin J.; Yang, Weilian; Palmer, Alycia M.; Turro, Claudia; Weldon, Michael; Bell, Erica Hlavin; Mo, Xiaokui

2015-01-01

The purposes of this study were (i) to investigate the differences in effects between 160-kV low-energy and 6-MV high-energy X-rays, both by computational analysis and in vitro studies; (ii) to determine the effects of each on platinum-sensitized F98 rat glioma and murine B16 melanoma cells; and (iii) to describe the in vitro cytotoxicity and in vivo toxicity of a Pt(II) terpyridine platinum (Typ-Pt) complex. Simulations were performed using the Monte Carlo code Geant4 to determine enhancement in absorption of low- versus high-energy X-rays by Pt and to determine dose enhancement factors (DEFs) for a Pt-sensitized tumor phantom. In vitro studies were carried out using Typ-Pt and again with carboplatin due to the unexpected in vivo toxicity of Typ-Pt. Cell survival was determined using clonogenic assays. In agreement with computations and simulations, in vitro data showed up to one log unit reduction in surviving fractions (SFs) of cells treated with 1–4 µg/ml of Typ-Pt and irradiated with 160-kV versus 6-MV X-rays. DEFs showed radiosensitization in the 50–200 keV range, which fell to approximate unity at higher energies, suggesting marginal interactions at MeV energies. Cells sensitized with 1–5 or 7 µg/ml of carboplatin and then irradiated also showed a significant decrease (P < 0.05) in SFs. However, it was unlikely this was due to increased interactions. Theoretical and in vitro studies presented here demonstrated that the tumoricidal activity of low-energy X-rays was greater than that of high-energy X-rays against Pt-sensitized tumor cells. Determining whether radiosensitization is a function of increased interactions will require additional studies. PMID:25266332

Disruption of SLX4-MUS81 Function Increases the Relative Biological Effectiveness of Proton Radiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, Qi; Underwood, Tracy S.A.; Kung, Jong

2016-05-01

Purpose: Clinical proton beam therapy has been based on the use of a generic relative biological effectiveness (RBE) of ∼1.1. However, emerging data have suggested that Fanconi anemia (FA) and homologous recombination pathway defects can lead to a variable RBE, at least in vitro. We investigated the role of SLX4 (FANCP), which acts as a docking platform for the assembly of multiple structure-specific endonucleases, in the response to proton irradiation. Methods and Materials: Isogenic cell pairs for the study of SLX4, XPF/ERCC1, MUS81, and SLX1 were irradiated at the mid-spread-out Bragg peak of a clinical proton beam (linear energy transfer 2.5 keV/μm)more » or with 250 kVp x-rays, and the clonogenic survival fractions were determined. To estimate the RBE of the protons relative to cobalt-60 photons (Co60Eq), we assigned a RBE(Co60Eq) of 1.1 to x-rays to correct the physical dose measured. Standard DNA repair foci assays were used to monitor the damage responses, and the cell cycle distributions were assessed by flow cytometry. The poly(ADP-ribose) polymerase inhibitor olaparib was used for comparison. Results: Loss of SLX4 function resulted in an enhanced proton RBE(Co60Eq) of 1.42 compared with 1.11 for wild-type cells (at a survival fraction of 0.1; P<.05), which correlated with increased persistent DNA double-strand breaks in cells in the S/G{sub 2} phase. Genetic analysis identified the SLX4-binding partner MUS81 as a mediator of resistance to proton radiation. Both proton irradiation and olaparib treatment resulted in a similar prolonged accumulation of RAD51 foci in SLX4/MUS81-deficient cells, suggesting a common defect in the repair of DNA replication fork-associated damage. Conclusions: A defect in the FA pathway at the level of SLX4 results in hypersensitivity to proton radiation, which is, at least in part, due to impaired MUS81-mediated processing of replication forks that stall at clustered DNA damage. In vivo and clinical studies are needed to confirm these findings in human cancers.« less

Stem cells with FGF4-bFGF fused gene enhances the expression of bFGF and improves myocardial repair in rats

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, Xiang-Qi; Chen, Liang-Long, E-mail: xhzlyx@126.com; Fan, Lin

Highlights: • BFGF exists only in the cytoplasm of live cells. • BFGF cannot be secreted into the extracellular space to promote cell growth. • We combine the secretion-promoting signal peptide of FGF4. • We successfully modified BMSCs with the fused genes of FGF4-bFGF. • We promoted the therapeutic effects of transplanted BMSCs in myocardial infarction. - Abstract: The aim of this study was to investigate whether the modification of bone marrow-derived mesenchymal stem cells (BMSCs) with the fused FGF4 (fibroblast growth factor 4)-bFGF (basic fibroblast growth factor) gene could improve the expression and secretion of BFGF, and increase themore » efficacies in repairing infarcted myocardium. We used In-Fusion technique to construct recombinant lentiviral vectors containing the individual gene of bFGF, enhanced green fluorescent protein (EGFP), or genes of FGF4-bFGF and EGFP, and then transfected these lentiviruses into rat BMSCs. We conducted an in vitro experiment to compare the secretion of bFGF in BMSCs infected by these lentiviruses and also examined their therapeutic effects in the treatment of myocardial infraction in a rodent study. Sixty rats were tested in the following five conditions: Group-SHAM received only sham operation as controls; Group-AMI received only injection of placebo PBS buffer; Group-BMSC, Group-bFGF and Group-FGF4-bFGF received implantation of BMSCs with empty lentivirus, bFGF lentivirus, and FGF4-bFGF lentivirus, respectively. Our results found out that the transplanted FGF4-bFGF BMSCs had the highest survival rate, and also the highest myocardial expression of bFGF and microvascular density as evidenced by Western blotting and immunohistochemistry, respectively. As compared to other groups, the Group-FGF4-BFGF rats had the lowest myocardial fibrotic fraction, and the highest left ventricular ejection fraction. These results suggest that the modification of BMSCs with the FGF4-bFGF fused gene can not only increase the expression of bFGF but also improve its secretion. The FGF4-bFGF BMSCs thus can enhance the survival of the transplanted cells, diminish myocardial fibrosis, promote myocardial angiogenesis, and improve cardiac functions.« less

Disruption of SLX4-MUS81 Function Increases the Relative Biological Effectiveness of Proton Radiation.

PubMed

Liu, Qi; Underwood, Tracy S A; Kung, Jong; Wang, Meng; Lu, Hsiao-Ming; Paganetti, Harald; Held, Kathryn D; Hong, Theodore S; Efstathiou, Jason A; Willers, Henning

2016-05-01

Clinical proton beam therapy has been based on the use of a generic relative biological effectiveness (RBE) of ∼1.1. However, emerging data have suggested that Fanconi anemia (FA) and homologous recombination pathway defects can lead to a variable RBE, at least in vitro. We investigated the role of SLX4 (FANCP), which acts as a docking platform for the assembly of multiple structure-specific endonucleases, in the response to proton irradiation. Isogenic cell pairs for the study of SLX4, XPF/ERCC1, MUS81, and SLX1 were irradiated at the mid-spread-out Bragg peak of a clinical proton beam (linear energy transfer 2.5 keV/μm) or with 250 kVp x-rays, and the clonogenic survival fractions were determined. To estimate the RBE of the protons relative to cobalt-60 photons (Co60Eq), we assigned a RBE(Co60Eq) of 1.1 to x-rays to correct the physical dose measured. Standard DNA repair foci assays were used to monitor the damage responses, and the cell cycle distributions were assessed by flow cytometry. The poly(ADP-ribose) polymerase inhibitor olaparib was used for comparison. Loss of SLX4 function resulted in an enhanced proton RBE(Co60Eq) of 1.42 compared with 1.11 for wild-type cells (at a survival fraction of 0.1; P<.05), which correlated with increased persistent DNA double-strand breaks in cells in the S/G2 phase. Genetic analysis identified the SLX4-binding partner MUS81 as a mediator of resistance to proton radiation. Both proton irradiation and olaparib treatment resulted in a similar prolonged accumulation of RAD51 foci in SLX4/MUS81-deficient cells, suggesting a common defect in the repair of DNA replication fork-associated damage. A defect in the FA pathway at the level of SLX4 results in hypersensitivity to proton radiation, which is, at least in part, due to impaired MUS81-mediated processing of replication forks that stall at clustered DNA damage. In vivo and clinical studies are needed to confirm these findings in human cancers. Copyright © 2016 Elsevier Inc. All rights reserved.

Reactivation of Escherichia coli cells, inactivated by ultraviolet rays, with cell extracts of propionic acid bacteria: Fractionation of the extract

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vorob`eva, L.I.; Khodzhaev, E.Yu.; Ponomareva, G.M.

1995-01-01

Separation of Propionibacterium shermanii extract into fractions and testing them for their reactivating effect on UV-inactivated Escherichia coli AB-1157 cells showed that the activity was associated with the fraction of soluble proteins. The activity was not demonstrated in the fractions of RNA, DNA, ribosomes, or cell walls. Fractional salting out and subsequent testing of the fractions showed two active protein fractions: fraction I (20-40% of ammonium sulfate saturating concentration) and fraction II (60-80%). These fractions were separated by HPLC into seven and eight subfractions, respectively. Reactivating activity was showed in subfraction 4 (fraction I) and subfractions 5 and 6 (fractionmore » II). Electrophoresis showed five and four polypeptides in subfractions 4 and 5, respectively. Subfraction 6 (fraction II) contained one protein with a molecular mass of about 30 kDa. This protein, apparently, was responsible for the protective properties of fraction II. 9 refs., 2 figs., 4 tabs.« less

Impact of Thymoglobulin by Stem Cell Source (Peripheral Blood Stem Cell or Bone Marrow) After Myeloablative Stem Cell Transplantation From HLA 10/10-Matched Unrelated Donors: A Report From the Société Française de Greffe de Moelle et de Thérapie Cellulaire.

PubMed

Ravinet, Aurelie; Cabrespine, Aurelie; Socié, Gerard; Milpied, Noël; Yakoub Agha, Ibrahim; Nguyen, Stephanie; Michallet, Mauricette; Menard, Anne Lise; Maillard, Natacha; Mohty, Mohamad; Suarez, Felipe; Huynh, Anne; Marchand, Tony; Deteix, Clémence; Cassuto, Jill Patrice; Maury, Sebastien; Chevallier, Patrice; Reman, Oumedaly; Peffault de Latour, Régis; Bay, Jacques Olivier

2016-08-01

The impact of antithymocyte globulin (ATG) in the setting of a myeloablative conditioning transplantation remains controversial, especially when using bone marrow (BM) as the stem cell source. We therefore conducted a retrospective analysis to investigate the impact of ATG in patients with acute myeloid leukemia or myelodysplastic syndrome receiving myeloablative conditioning followed by a matched 10 of 10 unrelated donor transplant from BM or peripheral blood stem cells (PBSCs). Our study included 356 patients conditioned with cyclophosphamide associated with fractionated total body irradiation or busulfan. Median follow-up was 17.6 months (range, 0-156). The ATG and PBSCs were the only variables that independently decreased the cumulative incidence (CI) of chronic graft-versus-host disease (GvHD) (hazards ratio [HR], 0.4; 95% CI, 0.21-0.73; P < 0.01; and HR, 0.53; 95% CI, 0.30-0.90; P = 0.02, respectively). The ATG had no impact on overall survival, disease-free survival, relapse, and nonrelapse mortality. In the PBSC group (n = 139), ATG was associated with a lower CI of both grades III to IV acute GvHD (HR, 0.17; 95% CI, 0.03-0.91; P = 0.04), chronic GvHD (HR, 0.31; 95% CI, 0.11-0.87; P = 0.03), and GvHD-free/relapse-free survival (HR, 0.48; 95% CI, 0.29-0.80; P < 0.01), whereas these correlations were not significant in the group of patients (n = 217) receiving BM (HR, 0.36; 95% CI, 0.11-1.93; P = 0.06 for grade III-IV acute GvHD; HR, 0.49; 95% CI, 0.22-1.06; P = 0.08 for chronic GvHD; and HR, 0.69; 95% CI, 0.46-1.01; P = 0.06 for GvHD-free/relapse-free survival). Although our results confirm the recommendation for ATG to be added after PBSC transplantation, no obvious benefit was identified using this approach in the setting of BM transplantation. Only prospective studies may yield definitive answers to this question.

Chemosensitizing effects of carbon-based nanomaterials in cancer cells: enhanced apoptosis and inhibition of proliferation as underlying mechanisms

NASA Astrophysics Data System (ADS)

Erdmann, Kati; Ringel, Jessica; Hampel, Silke; Rieger, Christiane; Huebner, Doreen; Wirth, Manfred P.; Fuessel, Susanne

2014-10-01

Recent studies have shown that carbon nanomaterials such as carbon nanofibres (CNFs) and multi-walled carbon nanotubes (CNTs) can exert antitumor activities themselves and sensitize cancer cells to conventional chemotherapeutics such as carboplatin and cisplatin. In the present study, the chemosensitizing effect of CNFs and CNTs on cancer cells of urological origin was investigated regarding the underlying mechanisms. Prostate cancer (DU-145, PC-3) and bladder cancer (EJ28) cells were treated with carbon nanomaterials (CNFs, CNTs) and chemotherapeutics (carboplatin, cisplatin) alone as well as in combination for 24 h. Forty-eight (EJ28) or 72 h (DU-145, PC-3) after the end of treatment the effects on cellular proliferation, clonogenic survival, cell death rate and cell cycle distribution were evaluated. Depending on the cell line, simultaneous administration of chemotherapeutics and carbon nanomaterials produced an additional inhibition of cellular proliferation and clonogenic survival of up to 77% and 98%, respectively, compared to the inhibitory effects of the chemotherapeutics alone. These strongly enhanced antiproliferative effects were accompanied by an elevated cell death rate, which was predominantly mediated via apoptosis and not by necrosis. The antitumor effects of combinations with CNTs were less pronounced than those with CNFs. The enhanced effects of the combinatory treatments on cellular function were mostly of additive to partly synergistic nature. Furthermore, cell cycle analysis demonstrated an arrest at the G2/M phase mediated by a monotreatment with chemotherapeutics. Following combinatory treatments, mostly less than or nearly additive increases of cell fractions in the G2/M phase could be observed. In conclusion, the pronounced chemosensitizing effects of CNFs and CNTs were mediated by an enhanced apoptosis and inhibition of proliferation. The combination of carbon-based nanomaterials and conventional chemotherapeutics represents a novel approach in cancer therapy to bypass chemoresistance by minimizing the chemotherapeutic dosing.