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1

Human Central Nervous System Distribution of c\\/s-Diamminedichloroplatinum and Use as a Radiosensitizer in Malignant Brain Tumors1  

Microsoft Academic Search

The human central nervous system pharmacology of c\\/'s- diamminedichloroplatinum (CDDP) was studied, and trials were initiated of CDDP as a radiosensitizer in the treatment of malignant primary brain tumors. Samples were assayed for platinum using X-ray-dispersive fluorescence spectrometry. Platinum was barely detectable in cerebrospinal fluid from two patients and was not detectable (<0.10 ftg\\/ml) in cerebrospinal fluid from three patients

David J. Stewart; Milam Leavens; Moshe Maor; Lyn Feun; Mario Luna; Jeanne Bonura; Richard Caprioli; Ti Li Loo; Robert S. Benjamin

2

PKB/Akt mediates radiosensitization by the signaling inhibitor LY294002 in human malignant gliomas.  

PubMed

The phosphoinositide 3-kinase (PI3-kinase) signaling pathway is frequently aberrantly activated in glioblastoma multiforme (GM) by mutation or loss of the 3' phospholipid phosphatase PTEN. PTEN abnormalities result in inappropriate signaling to downstream molecules including protein kinase B (PKB/Akt), and mammalian target of rapamycin (mTOR). PI3-kinase activation increases resistance to radiation-induced cell death; conversely, PI3-kinase inhibition enhances the sensitivity of tumors to radiation. The effects of LY294002, a biochemical inhibitor of PI3-kinase, on the response to radiation were examined in the PTEN mutant glioma cell line U251 MG. Low doses of LY294002 sensitized U251 MG to clinically relevant doses of radiation. In contrast to LY294002, rapamycin, an inhibitor of mTOR, did not result in radiosensitization. We demonstrate that among multiple known targets of LY294002, PI3-kinase is the most likely molecule responsible for LY294002-induced radiosensitization. Furthermore, using a myristoylated PKB/Akt construct, we identified PKB/Akt as the downstream molecule that mediates the synergistic cytotoxicity between LY294002 and radiation. Thus PI3-kinase dysregulation may contribute to the notable radioresistance of GM tumors and inhibition of PKB/Akt offers an excellent target to enhance radiosensitivity. PMID:15735908

Nakamura, Jean L; Karlsson, Amelia; Arvold, Nils D; Gottschalk, Alexander R; Pieper, Russell O; Stokoe, David; Haas-Kogan, Daphne A

2005-02-01

3

Microwave hyperthermia radiosensitized iridium-192 for recurrent brain malignancy  

SciTech Connect

Twenty-one patients whose solitary detectable biopsy proven recurrent brain malignancies produced Central Nervous System (CNS) symptoms warranting further intervention received 60-minute 43 degrees C (180 degree-minute) interstitial 2450 MHz microwave hyperthermia fractions. All received brain teletherapy prior to recurrence. The first 15 received no brachytherapy and served as a toxicity pilot. All 15 enjoyed neurologic improvement, 12 symptomatic improvement, and 12 objective response as mass reduction and/or tumor necrosis. The next 6 patients were selected with more favorable Karnofsky performance status, no known active malignancy elsewhere, and received afterloading Ir-192 interstitial implantation juxtaposed to radiosensitizing hyperthermia. Volume dose varied from 1000 to 2245 rad, and dose rate from 40 to 100 rad/hr. Dose selected varied as a function of pre-recurrence teletherapy dose, general condition, histologic type, and volume. Neurosurgical debulking, if technically indicated through no additional aperture or trauma, was permitted if consistent with preservation of neurological function. Six enjoyed neurologic improvement, symptom reduction, and objective tumor response; three remain alive, and one experienced transient improvement. Complications, histologic subtypes, autopsy findings, stereotactic approach, thermal monitoring methods and CT follow-up of objective response are presented along with computer dosimetry and isotherm chart. Our microtraumatic universal catheter technique for CT guided stereotactic biopsy, aspiration, decompression, thermal sensory loop, thermalization antennae, and brachytherapy without multiple trauma nor changing catheters is stressed. The rationale for combined modes peculiar to the CNS will be outlined.2+ Proposal for incorporating controlled-release ARA-C chemotherapy polymer micro-rods into the interstitial format will be offered.

Borok, T.L.; Winter, A.; Laing, J.; Paglione, R.; Sterzer, F.; Sinclair, I.; Plafker, J. (Metcalf Institute-Radiation Oncology, Orange, NJ (USA))

1988-03-01

4

Radiosensitization of malignant gliomas following intracranial delivery of paclitaxel biodegradable polymer microspheres.  

PubMed

Object The aim of this study was to demonstrate that paclitaxel could function as a radiosensitizer for malignant glioma in vitro and in vivo. Methods The radiosensitizing effect of paclitaxel was tested in vitro using the human U373MG and rat 9L glioma cell lines. Cell cycle arrest in response to paclitaxel exposure was quantified by flow cytometry. Cells were subsequently irradiated, and toxicity was measured using the clonogenic assay. In vivo studies were performed in Fischer 344 rats implanted with intracranial 9L gliosarcoma. Rats were treated with control polymer implants, paclitaxel controlled-release polymers, radiotherapy, or a combination of the 2 treatments. The study end point was survival. Results Flow cytometry demonstrated G2-M arrest in both U373MG and 9L cells following 6-12 hours of paclitaxel exposure. The order in which the combination treatment was administered was significant. Exposure to radiation treatment (XRT) during the 6-12 hours after paclitaxel treatment resulted in a synergistic reduction in colony formation. This effect was greater than the effect from either treatment alone and was also greater than the effect of radiation exposure followed by paclitaxel. Rats bearing 9L gliosarcoma tumors treated with paclitaxel polymer administration followed by single-fraction radiotherapy demonstrated a synergistic improvement in survival compared with any other treatment, including radiotherapy followed by paclitaxel treatment. Median survival for control animals was 13 days; for those treated with paclitaxel alone, 21 days; for those treated with XRT alone, 21 days; for those treated with XRT followed by paclitaxel, 45 days; and for those treated with paclitaxel followed by XRT, more than 150 days (p < 0.0001). Conclusions These results indicate that paclitaxel is an effective radiosensitizer for malignant gliomas because it renders glioma cells more sensitive to ionizing radiation by causing G2-M arrest, and induces a synergistic response to chemoradiotherapy. PMID:24605841

Gabikian, Patrik; Tyler, Betty M; Zhang, Irma; Li, Khan W; Brem, Henry; Walter, Kevin A

2014-05-01

5

Hyaluronan in human malignancies  

SciTech Connect

Hyaluronan, a major macropolysaccharide in the extracellular matrix of connective tissues, is intimately involved in the biology of cancer. Hyaluronan accumulates into the stroma of various human tumors and modulates intracellular signaling pathways, cell proliferation, motility and invasive properties of malignant cells. Experimental and clinicopathological evidence highlights the importance of hyaluronan in tumor growth and metastasis. A high stromal hyaluronan content is associated with poorly differentiated tumors and aggressive clinical behavior in human adenocarcinomas. Instead, the squamous cell carcinomas and malignant melanomas tend to have a reduced hyaluronan content. In addition to the stroma-cancer cell interaction, hyaluronan can influence stromal cell recruitment, tumor angiogenesis and epithelial-mesenchymal transition. Hyaluronan receptors, hyaluronan synthases and hyaluronan degrading enzymes, hyaluronidases, are involved in the modulation of cancer progression, depending on the tumor type. Furthermore, intracellular signaling and angiogenesis are affected by the degradation products of hyaluronan. Hyaluronan has also therapeutic implications since it is involved in multidrug resistance.

Sironen, R.K. [Institute of Clinical Medicine, Pathology and Forensic Medicine, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio (Finland) [Institute of Clinical Medicine, Pathology and Forensic Medicine, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio (Finland); Department of Pathology, Kuopio University Hospital, P.O. Box 1777, FI-70211 Kuopio (Finland); Tammi, M.; Tammi, R. [Institute of Biomedicine, Anatomy, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio (Finland)] [Institute of Biomedicine, Anatomy, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio (Finland); Auvinen, P.K. [Department of Oncology, Kuopio University Hospital, P.O. Box 1777, FI-70211 Kuopio (Finland)] [Department of Oncology, Kuopio University Hospital, P.O. Box 1777, FI-70211 Kuopio (Finland); Anttila, M. [Institute of Clinical Medicine, Pathology and Forensic Medicine, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio (Finland) [Institute of Clinical Medicine, Pathology and Forensic Medicine, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio (Finland); Department of Gynecology and Obstetrics, Kuopio University Hospital, P.O. Box 1777, FI-70211 Kuopio (Finland); Kosma, V-M., E-mail: Veli-Matti.Kosma@uef.fi [Institute of Clinical Medicine, Pathology and Forensic Medicine, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio (Finland); Department of Pathology, Kuopio University Hospital, P.O. Box 1777, FI-70211 Kuopio (Finland)

2011-02-15

6

Induction and Characterization of Human Glioma Clones With Different Radiosensitivities  

PubMed Central

Abstract To facilitate investigation of the molecular mechanisms of tumor cell radiosensitivities, we have generated a set of clones with different radiosensitivities from a human glioma cell line U-251 MG-Ho. Forty-four colonies were isolated by subjecting parent cells to the mutagen N-methylnitrosourea and then irradiating these cells with increasing doses of x-rays. About half of the clones displayed different radiosensitivities than the parent cells. We selected one of the most sensitive clones (X3i) and one of the most resistant clones (Y6) for further study. Isoeffective doses for these two clones differed by about a factor of 1.7; the relative radiosensitivities of both clones were stable for at least 30 cell culture passages. These two clones do not differ significantly in either the induction or repair of radiation-induced DNA double-strand breaks as measured by pulsed field gel electrophoresis. Radiation-induced apoptosis measured by terminal deoxynucleotide transferase-mediated dUTP nick end labeling assay and micronucleus formation were similar in both clones. However, potentially lethal damage repair was greater in the radioresistant Y6 clone than in the radiosensitive X3i clone as determined by colony-forming efficiency assay.

Wang, Jingli; Hu, Lily; Gupta, Nalin; Shamseldin, Tod; Ozawa, Tomoko; Klem, Jack; Cardell, Monika; Deen, Dennis F

1999-01-01

7

2-Deoxy-D-glucose and 6-aminonicotinamide-mediated Nrf2 down regulation leads to radiosensitization of malignant cells via abrogation of GSH-mediated defense.  

PubMed

Enhanced level of nuclear erythroid-related factor-2 (Nrf2) has been associated with cancer chemo/radioresistance. Therefore, the role of Nrf2 in radiosensitization of malignant cells induced by a combination of 2-deoxy-D-Glucose (2-DG) and 6-aminonicotinamide (6-AN) was investigated. Two established human malignant cells lines namely KB (head and neck squamous carcinoma) and BMG-1 (cerebral glioma) were used. Following treatment with a combination of 2-DG (5 mM) and 6-AN (5 ?M), irradiated (2Gy) KB and BMG-1 cells were assessed for protein level of Nrf2, Keap1 and ?-glutamylcysteine synthetase (?-GCS) by western blotting and mRNA expression of ?-GCS, glutathione reductase (GR) and glutathione peroxidase (GPx1) by RT-PCR at 24 hours post treatment. A significant decrease in the level of Nrf2 with a concomitant increase in Keap1 was observed in both the irradiated malignant cells at 24 hours following treatment with combination (2-DG + 6-AN). Down regulation of ?-GCS, GR and GPx1 at 24 hours following treatment with combination (2-DG + 6-AN) resulted in abrogation of glutathione (GSH)-mediated defense in both the irradiated malignant cells. Eventual accumulation of ROS led to radiosensitization of both the malignant cells. These results indicate that deregulated Nrf2-Keap1 signalling leads to the radiosensitization of malignant cells due to abrogated glutathione defense. Metabolic modification-mediated down regulation of Nfr2 and its downstream signalling may have a potential of improving tumour radiotherapy. PMID:22946929

Sharma, Pradeep Kumar; Varshney, Rajeev

2012-12-01

8

Enhanced G2 chromatid radiosensitivity, an early stage in the neoplastic transformation of human epidermal keratinocytes in culture  

SciTech Connect

A deficiency in DNA repair, manifest as enhanced chromatid radiosensitivity during the G2 phase of the cell cycle, together with a proliferative stimulus such as that provided by active oncogenes may be necessary and sufficient for the malignant neoplastic transformation of human keratinocytes in culture. Normal epidermal keratinocytes established as continuous cell lines by transfection with pSV3-neo or infection with adeno 12-SV40 hybrid virus developed enhanced G2 chromatid radiosensitivity after 18 passages in culture. In contrast to cells from primary or secondary culture, these cells could be transformed to malignant neoplastic cells by infection with Kirsten murine sarcoma virus containing the Ki-ras oncogene or in one line by the chemical carcinogen, N-methyl-N'-nitro-N-nitrosoguanidine; both of these agents produced a marked proliferative response. Cytological heterogeneity and karyotypic instability characterized the cells during their progression to neoplasia. These results are interpreted in terms of a mechanism for neoplastic transformation.

Gantt, R.; Sanford, K.K.; Parshad, R.; Price, F.M.; Peterson, W.D. Jr.; Rhim, J.S.

1987-03-01

9

Differential radio-sensitivities of human chromosomes 1 and 2 in one donor in interphase and metaphase-spreads after 60Co ?-irradiation  

Microsoft Academic Search

BACKGROUND: Radiation-induced chromosome aberrations lead to a plethora of detrimental effects at cellular level. Chromosome aberrations provide broad spectrum of information ranging from probability of malignant transformation to assessment of absorbed dose. Studies mapping differences in radiation sensitivities between human chromosomes are seldom undertaken. Consequently, health risk assessment based on radio-sensitivities of individual chromosomes may be erroneous. Our efforts in

Rupak Pathak; Adarsh Ramakumar; Uma Subramanian; Pataje GS Prasanna

2009-01-01

10

Radiosensitization effects of berberine on human breast cancer cells.  

PubMed

Berberine, an isoquinoline derivative alkaloid, has recently been shown to have antitumor activity. The present study aimed to investigate the effects of the concomitant administration of berberine and radiation on breast cancer. The effects of berberine on the radiosensitivity of MCF-7 and MDA-MB-468 cells were evaluated by using cell clonogenic assays. Cells pre-treated with berberine or dimethyl sulfoxide (DMSO) for 24 h were irradiated using a Faxitron Cabinet X-ray System to deliver the indicated doses (0, 1, 2, 3 and 4 Gy). Changes in cell cycle distribution were determined by flow cytometry. ?-H2AX foci were detected by immunofluorescence staining. The levels of Ku70, Ku86 and RAD51 proteins were evaluated by western blot analysis. We observed that berberine increased the MCF-7 and MDA-MB-468 cell radiosensitivity with cell clonogenic assays. the radiation-induced G2/M cell cycle delay was reduced in the MCF-7 cells pre-teated with berberine. Berberine pre-treatment prolonged the persistence of DNA double-strand breaks in the MCF-7 cell line. In comparison with the control cells, the protein levels of RAD51 were decreased in the MCF-7 and MDA-MB-468 cells treated with berberine, and in the cells pre-treated with 15 µM berberine for 24 h, the level of RAD51 protein decreased significantly at the indicated time-points (0, 2, 6 and 24 h) following X-ray exposure. In conclusion, berberine sensitizes human breast cancer cells to ionizing radiation by inducing cell cycle arrest and the downregulation of the homologous recombination repair protein, RAD51. Berberine may be a promising radiosensitizer for the treatment of breast cancer. PMID:22895634

Wang, Jing; Liu, Qiao; Yang, Qifeng

2012-11-01

11

Lack of a correlation between micronucleus formation and radiosensitivity in established and primary cultures of human tumours.  

PubMed Central

The radiation-induced genotoxic damage in three established cell lines and 15 primary cultures of human malignant melanoma and ovarian carcinoma showing different radiosensitivity was tested by the cytokinesis-block micronucleus assay. A dose-related increase in micronucleus frequency was observed in all the cell systems. The mean number of micronuclei per Gy of ionising radiation per binucleated cell was respectively 0.44 +/- 0.0075 and 0.43 +/- 0.04 for M14 and JR8 malignant melanoma cell lines and 0.19 +/- 0.013 for the A2780 ovarian cancer cell line. The number of micronuclei did not rank the cell lines in the same order of radiosensitivity as clonogenic cell survival, which showed a surviving fraction at 2 Gy of 0.38 +/- 0.02 for JR8, 0.34 +/- 0.05 for M14 and 0.22 +/- 0.007 for A2780. As regards primary tumour cultures, no correlation was observed between micronucleus induction and surviving fraction at 2 Gy. In conclusion, the discrepancy we observed between micronucleus formation and cell death raises doubts about the potential of the micronucleus assay as a preclinical means to predict radiosensitivity. Images Figure 1

Villa, R.; Zaffaroni, N.; Gornati, D.; Costa, A.; Silvestrini, R.

1994-01-01

12

Lack of a correlation between micronucleus formation and radiosensitivity in established and primary cultures of human tumours.  

PubMed

The radiation-induced genotoxic damage in three established cell lines and 15 primary cultures of human malignant melanoma and ovarian carcinoma showing different radiosensitivity was tested by the cytokinesis-block micronucleus assay. A dose-related increase in micronucleus frequency was observed in all the cell systems. The mean number of micronuclei per Gy of ionising radiation per binucleated cell was respectively 0.44 +/- 0.0075 and 0.43 +/- 0.04 for M14 and JR8 malignant melanoma cell lines and 0.19 +/- 0.013 for the A2780 ovarian cancer cell line. The number of micronuclei did not rank the cell lines in the same order of radiosensitivity as clonogenic cell survival, which showed a surviving fraction at 2 Gy of 0.38 +/- 0.02 for JR8, 0.34 +/- 0.05 for M14 and 0.22 +/- 0.007 for A2780. As regards primary tumour cultures, no correlation was observed between micronucleus induction and surviving fraction at 2 Gy. In conclusion, the discrepancy we observed between micronucleus formation and cell death raises doubts about the potential of the micronucleus assay as a preclinical means to predict radiosensitivity. PMID:7981062

Villa, R; Zaffaroni, N; Gornati, D; Costa, A; Silvestrini, R

1994-12-01

13

Re-evaluation of in vitro radiosensitivity of human fibroblasts of different genetic origins.  

PubMed

A statistical analysis of the radiosensitivity of 204 different survival curves of nontransformed human fibroblast cell strains of different genetic origins was made using three criteria: the multi-target one-hit model (characterized by parameters n and D0), the surviving fraction for a 2 Gy dose (S2) and the mean inactivation dose (D). D is found to be the best parameter for characterization of anomalous radiosensitivity linked to a genetic disorder and for discrimination between groups of cell strains of differing radiosensitivity. Its use allows the description of a range of 'normal' radiosensitivity for control fibroblasts and the classification of the various genetic disorders as a function of their mean radiosensitivity expressed in terms of D. Nine groups of cell strains appear to exhibit radiosensitivity which differs significantly from that of the controls: seven groups are hypersensitive (ataxia-telangiectasia homozygotes and heterozygotes, Cockayne's syndrome, Gardner's syndrome, 5-oxoprolinuria homozygotes and heterozygotes, Fanconi's anaemia) and two groups are more radioresistant (fibroblasts from retinoblastoma patients and from individuals with chromosome 13 anomalies). Since the coupled parameter n and D0 failed to discriminate between the radiosensitivity of the different genetic groups, we recommend the use of D to make an intercomparison of intrinsic radiosensitivity of nontransformed human fibroblasts. PMID:3488286

Deschavanne, P J; Debieu, D; Fertil, B; Malaise, E P

1986-08-01

14

Dolichol biosynthesis in human malignant cells.  

PubMed Central

Cholesterol, ubiquinone and dolichol biosynthesis from mevalonic acid was measured in non-malignant and malignant cultured human lymphocytes, freshly isolated human mononuclear leucocytes and in cultured human hepatoma cells. The relative flux of mevalonate into ubiquinone, dilichol and cholesterol was not significantly different between malignant and non-malignant cells, although the extent of labelling of each product was an order of magnitude greater in the malignant cultured cells. The most prominent dolichol isolated from total cellular lipid and synthesized in short-term labelling of cultured leukaemic cells had a chain length one isoprene unit shorter than that observed in normal human cells. Cultured human hepatoma cells and mononuclear leucocytes isolated from the peripheral blood of individuals with lymphoblastic and myelogenic leukaemia similarly synthesized shorter-chain dolichols. The dolichols made in cultured non-tumorigenic cells, freshly isolated mononuclear leucocytes from a normal individual or a patient with non-haematological malignancy had normal chain length.

Henry, A; Stacpoole, P W; Allen, C M

1991-01-01

15

Studies of the in vivo radiosensitivity of human skin fibroblasts  

PubMed Central

Background and Purpose To examine the radiosensitivity of skin cells obtained directly from the irradiated skin of patients undergoing fractionated radiation treatment prior to surgery for treatment of soft tissue sarcoma (STS) and to determine if there was a relationship with the development of wound healing complications associated with the surgery post-radiotherapy. Methods Micronucleus (MN) formation was measured in cells (primarily dermal fibroblasts) obtained from human skin at their first division after being removed from STS patients during post radiotherapy surgery (2-9 weeks after the end of the radiotherapy). At the time of radiotherapy (planned tumor dose - 50 Gy in 25 daily fractions) measurements were made of surface skin dose at predetermined marked sites. Skin from these sites was obtained at surgery and cell suspensions were prepared directly for the cytokinesis-blocked MN assay. Cultured strains of the fibroblasts were also established from skin nominally outside the edge of the radiation beam and DNA damage (MN formation) was examined following irradiation in vitro for comparison with the results from the in situ irradiations. Results Extensive DNA damage (MN) was detectable in fibroblasts from human skin at extended periods after irradiation (2-9 weeks after the end of the 5-week fractionated radiotherapy). Analysis of skin receiving a range of doses demonstrated that the level of damage observed was dose dependent. There was no clear correlation between the level of damage observed after irradiation in situ and irradiation of cell strains in culture. Similarly, there was no correlation between the extent of MN formation following in situ irradiation and the propensity for the patient to develop wound healing complications post surgery. Conclusions Despite the presence of DNA damage in dermal fibroblasts weeks after the end of the radiation treatment, there was no relationship between this damage and wound healing complications following surgery post irradiation. These results suggest that factors other than the radiosensitivity of the skin fibroblasts likely also play a role in wound healing in deep wound sites associated with surgery for STS following radiation therapy.

Hill, R. P.; Kaspler, P.; Griffin, A.M.; O'Sullivan, B.; Catton, C.; Alasti, H.; Abbas, A.; Heydarian, M.; Ferguson, P.; Wunder, J.S.; Bell, R.S.

2007-01-01

16

Dihydroartemisinin enhances radiosensitivity of human glioma cells in vitro  

Microsoft Academic Search

Purpose: The antimalarial agent, artemisinin, also confers cancer-specific cytotoxic effects by reacting with ferrous iron atoms\\u000a to form free radicals. Here, we investigated the radiosensitizing effects of dihydroartemisinin on glioma cells and assessed\\u000a some possible mechanisms for these effects. Materials and methods: U373MG glioma cells treated with various concentrations of dihydroartemisinin plus radiation, and efficiency of radiosensitization\\u000a was assessed by

S. J. Kim; M. S. Kim; J. W. Lee; C. H. Lee; H. Yoo; S. H. Shin; M. J. Park; S. H. Lee

2006-01-01

17

Antiproliferation and radiosensitization of caffeic acid phenethyl ester on human medulloblastoma cells  

Microsoft Academic Search

Purpose: To investigate antiproliferative and radiosensitizing effects of caffeic acid phenethyl ester (CAPE) on medulloblastoma\\u000a (MB) Daoy cells. Methods and materials: Daoy cells were treated with CAPE in different concentrations and assessed for cell viability, apoptosis, cell cycles, cyclin\\u000a B1 expressions, radiosensitization and chemosensitization. Human astroglia SVGp12 cells were treated with CAPE to present\\u000a the possible protection or complication effects

Yi-Hsien Lin; Jen-Hwey Chiu; Wen-Ser Tseng; Tai-Tong Wong; Shih-Hwa Chiou; Sang-Hue Yen

2006-01-01

18

Fulvestrant radiosensitizes human estrogen receptor-positive breast cancer cells  

SciTech Connect

Highlights: ? Fulvestrant radiosensitizes MCF-7 cells. ? Fulvestrant increases G1 arrest and decreases S phase in MCF-7 cells. ? Fulvestrant down-regulates DNA-PKcs and RAD51 in MCF-7 cells. -- Abstract: The optimal sequencing for hormonal therapy and radiation are yet to be determined. We utilized fulvestrant, which is showing promise as an alternative to other agents in the clinical setting of hormonal therapy, to assess the cellular effects of concomitant anti-estrogen therapy (fulvestrant) with radiation (F + RT). This study was conducted to assess the effects of fulvestrant alone vs. F + RT on hormone-receptor positive breast cancer to determine if any positive or negative combined effects exist. The effects of F + RT on human breast cancer cells were assessed using MCF-7 clonogenic and tetrazolium salt colorimetric (MTT) assays. The assays were irradiated with a dose of 0, 2, 4, 6 Gy ± fulvestrant. The effects of F + RT vs. single adjuvant treatment alone on cell-cycle distribution were assessed using flow cytometry; relative expression of repair proteins (Ku70, Ku80, DNA-PKcs, Rad51) was assessed using Western Blot analysis. Cell growth for radiation alone vs. F + RT was 0.885 ± 0.013 vs. 0.622 ± 0.029 @2 Gy, 0.599 ± 0.045 vs. 0.475 ± 0.054 @4 Gy, and 0.472 ± 0.021 vs. 0.380 ± 0.018 @6 Gy RT (p = 0.003). While irradiation alone induced G2/M cell cycle arrest, the combination of F + RT induced cell redistribution in the G1 phase and produced a significant decrease in the proportion of cells in G2 phase arrest and in the S phase in breast cancer cells (p < 0.01). Furthermore, levels of repair proteins DNA-PKcs and Rad51 were significantly decreased in the cells treated with F + RT compared with irradiation alone. F + RT leads to a decrease in the surviving fraction, increased cell cycle arrest, down regulating of nonhomologous repair protein DNA-PKcs and homologous recombination repair protein RAD51. Thus, our findings suggest that F + RT increases breast cancer cell radiosensitivity compared with radiation alone. These findings have salient implications for designing clinical trials using fulvestrant and radiation therapy.

Wang, Jing, E-mail: wangstella5@163.com [Department of Breast Surgery, Qilu Hospital, Shandong Univeristy, Wenhua Xi Road 107, Shandong Province (China) [Department of Breast Surgery, Qilu Hospital, Shandong Univeristy, Wenhua Xi Road 107, Shandong Province (China); Department of Oncology, Affiliated Hospital of Qingdao University Medical College, Shandong Province (China); Yang, Qifeng, E-mail: qifengy@gmail.com [Department of Breast Surgery, Qilu Hospital, Shandong Univeristy, Wenhua Xi Road 107, Shandong Province (China)] [Department of Breast Surgery, Qilu Hospital, Shandong Univeristy, Wenhua Xi Road 107, Shandong Province (China); Haffty, Bruce G., E-mail: hafftybg@umdnj.edu [Department of Radiation Oncology, UMDNJ-Robert Wood Johnson School of Medicine, Cancer Institute of New Jersey, NB (United States); Li, Xiaoyan, E-mail: xiaoyanli1219@gmail.com [Department of Oncology, Affiliated Hospital of Qingdao University Medical College, Shandong Province (China)] [Department of Oncology, Affiliated Hospital of Qingdao University Medical College, Shandong Province (China); Moran, Meena S., E-mail: meena.moran@yale.edu [Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, CT (United States)

2013-02-08

19

Radiosensitization of human breast cancer cells to ultraviolet light by 5-fluorouracil  

PubMed Central

Ultraviolet light B (UVB) phototherapy is widely used to treat dermatological diseases and therefore may be a potential optional strategy in the treatment of a skin lesion infiltrated by a malignant tumor. Currently, little is known regarding the effect of UVB phototherapy on human breast cancer cells. The present study aimed to investigate the effect of UVB phototherapy, as well as the potential effect of 5-fluorouracil (5-FU), the first-line anticancer drug for breast cancer, on radiosensitizing MCF-7 human breast cancer cells, in an attempt to develop new therapeutic strategies for the treatment of locoregional recurrence of breast cancer. MCF-7 cells were incubated in the presence of 5-FU for 48 h, and UVB irradiation at 750 mJ/cm2 was administered in the midterm of 5-FU treatment. The viability of MCF-7 cells was analyzed by the trypan blue staining method. Apoptosis was quantified by flow cytometry and Hoechst 33258 staining. The cell cycle was evaluated by flow cytometry after the staining of cells with propidium iodide. The combination treatment of 5-FU and UVB resulted in a strong potentiation of the inhibitory effect of MCF-7 cell growth, dependent on the intra-S phase cell cycle arrest and induction of apoptosis, when compared to treatment with 5-FU or UVB alone. In conclusion, 5-FU sensitized human breast cancer cells to UVB phototherapy, and this combination therapy is an effective and promising strategy for the treatment of breast cancer, particularly for locoregional recurrence.

SASAKI, KAZUHITO; TSUNO, NELSON H.; SUNAMI, EIJI; KAWAI, KAZUSHIGE; SHUNO, YASUTAKA; HONGO, KUMIKO; HIYOSHI, MASAYA; KANEKO, MANABU; MURONO, KOJI; TADA, NORIKO; NIREI, TAKAKO; KITAYAMA, JOJI; TAKAHASHI, KOKI; NAGAWA, HIROKAZU

2011-01-01

20

Association between cellular radiosensitivity and G1/G2 checkpoint proficiencies in human cholangiocarcinoma cell lines.  

PubMed

Cholangiocarcinoma is a destructive malignancy with a poor prognosis and lack of effective medical treatment. Radiotherapy is an alternative treatment for patients with unresectable cholangiocarcinoma. However, there are limited data on the radiation responsiveness of individual cholangiocarcinoma cells, which is a key factor that influences radiation treatment outcome. In this study, we found that cholangiocarcinoma cell lines differ remarkably in their radiosensitivity. The variation of radiosensitivity of cholangiocarcinoma cells correlates with their p53 status and existing G1 and/or G2 checkpoint defects. We also demonstrated the potential of checkpoint kinase Chk1/2 inhibition on the enhancement of the radiosensitivity of cholangiocarcinoma cells. Thus, this study provides useful information for predicting radiation response and provides evidence for the enchantment of radiotherapeutic efficiency by targeting checkpoint kinase Chk1/2 in some subpopulations of cholangiocarcinoma patients. PMID:24969815

Hematulin, Arunee; Sagan, Daniel; Sawanyawisuth, Kanlayanee; Seubwai, Wunchana; Wongkham, Sopit

2014-09-01

21

Minimally cytotoxic doses of temozolomide produce radiosensitization in human glioblastoma cells regardless of MGMT expression1  

PubMed Central

Concurrent treatment with the methylating agent temozolomide (TMZ) during radiotherapy (RT) has yielded the first significant improvement in survival of adult glioblastomas (GBMs) in the last three decades. However, improved survival is observed in a minority of patients, most frequently those whose tumors display CpG methylation of the MGMT (O6-methylguanine-DNA methyltransferase) promoter, and adult GBMs remain invariably fatal. Some, though not all, pre-clinical studies have shown that TMZ can increase radiosensitivity in GBM cells that lack MGMT, the sole activity in human cells that removes O6-meG from DNA. Here, we systematically examined the TMZ dose dependence of radiation killing in established GBM cell lines that differ in ability to remove O6-meG or tolerate its lethality. Our results show that minimally cytotoxic doses of TMZ can produce dose-dependent radiosensitization in MGMT-deficient cells, MGMT-proficient cells, and MGMT-deficient cells that lack mismatch repair, a process that renders cells tolerant of the lethality of O6-meG. In cells that either possess or lack MGMT activity, radiosensitization requires exposure to TMZ before but not after radiation, and is accompanied by formation of double-strand breaks within 45 min of radiation. Moreover, suppressing alkyladenine-DNA glycosylase, the only activity in human cells that excises 3-meA from DNA, reduces the TMZ dose dependence of radiosensitization, indicating that radiosensitization is mediated by 3-meA as well as by O6-meG. These results provide novel information on which to base further mechanistic study of radiosensitization by TMZ in human GBM cells, and to develop strategies to improve the outcome of concurrent TMZ-RT.

Bobola, Michael S.; Kolstoe, Douglas D.; Blank, A.; Silber, John R.

2010-01-01

22

Heterogeneity in antigenic expression and radiosensitivity in human colon carcinoma cell lines.  

PubMed

A panel of human colon carcinoma cell lines were characterized regarding both antigenic heterogeneity and variations in radiosensitivity. Monoclonal antibodies were used to study the expression of carcinoembryonic antigen (CEA), gastrointestinal cancer antigen (GICA or CA 19-9) and carcinoma-associated antigen (CA-50). Radiosensitivity was studied with the clonogenic survival technique. Three cell lines, LS 174T, HCTC, and SW 1116 stained positive for all three antigens. HT-29 was positive for CA 19-9 and CA-50 whereas Caco-2 was positive for CEA and CA 19-9. The cell lines SW 620 and LIM 1215 only stained positive for one of the antigens, CA-50 and CEA, respectively. In nearly all positive cases the stainings were very heterogeneous with mixtures of positive and negative cells. One exception was the HCTC cells which stained homogeneously for the CA 19-9 and CA-50 antigens. The neuroendocrinelike COLO 320 cells were negative in all cases. The radiosensitivity varied strongly between the cell lines with Dq-values between 0.8 and 1.9, extrapolation numbers between 2.0 and 4.7, Do-values between 1.1 and 2.8. The surviving fraction at 2 Gy varied between 0.3 and 0.7 with HCTC as the most radiosensitive and HT-29 as the most radioresistant cell line. Thus, there were differences in antigenic expression and intrinsic radiosensitivity between the cell-lines and antigenic heterogeneities within each cell line. The analyzed panel of cell lines will be valuable in studies of dose-effect relations for monoclonal antibodies labeled with toxic radionuclides simulating both antigenic heterogeneity and variations in radiosensitivity. PMID:1757394

Frykholm, G; Glimelius, B; Richter, S; Carlsson, J

1991-12-01

23

Enhancement of P53-Mutant Human Colorectal Cancer Cells Radiosensitivity by Flavonoid Fisetin  

SciTech Connect

Purpose: The aim of this study was to investigate whether fisetin is a potential radiosensitizer for human colorectal cancer cells, which are relatively resistant to radiotherapy. Methods and Materials: Cell survival was examined by clonogenic survival assay, and DNA fragmentation was assessed by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assay. The effects of treatments on cell cycle distribution and apoptosis were examined by flow cytometry. Western blot analysis was performed to ascertain the protein levels of {gamma}-H2AX, phospho-Chk2, active caspase-3, PARP cleavage, phospho-p38, phospho-AKT, and phospho-ERK1/2. Results: Fisetin pretreatment enhanced the radiosensitivity of p53-mutant HT-29 human colorectal cancer cells but not human keratocyte HaCaT cells; it also prolonged radiation-induced G{sub 2}/M arrest, enhanced radiation-induced cell growth arrest in HT-29 cells, and suppressed radiation-induced phospho-H2AX (Ser-139) and phospho-Chk2 (Thr-68) in p53-mutant HT-29 cells. Pretreatment with fisetin enhanced radiation-induced caspase-dependent apoptosis in HT-29 cells. Fisetin pretreatment augmented radiation-induced phosphorylation of p38 mitogen-activated protein kinase, which is involved in caspase-mediated apoptosis, and SB202190 significantly reduced apoptosis and radiosensitivity in fisetin-pretreated HT-29 cells. By contrast, both phospho-AKT and phospho-ERK1/2, which are involved in cell proliferation and antiapoptotic pathways, were suppressed after irradiation combined with fisetin pretreatment. Conclusions: To our knowledge, this study is the first to provide evidence that fisetin exerts a radiosensitizing effect in p53-mutant HT-29 cells. Fisetin could potentially be developed as a novel radiosensitizer against radioresistant human cancer cells.

Chen Wenshu [Department of Life Science, Tzu Chi University, Hualien (China); Lee Yijang [Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, Taipei (China); Yu Yichu; Hsaio Chinghui [Department of Life Science, Tzu Chi University, Hualien (China)

2010-08-01

24

MicroRNA-218 Enhances the Radiosensitivity of Human Cervical Cancer via Promoting Radiation Induced Apoptosis  

PubMed Central

We previously reported frequent loss of microRNA-218 (miR-218) in cervical cancer, which was associated with tumor progression and poor prognosis. As microRNAs were found invovled in the regulation of radiosensitivity in various human cancers, we therefore aim to investigate the effects of miR-218 on radiosensitivity of cervical cancer in the present study. The clonogenic survival assay demonstrated that loss of miR-218 could predict radioresistance in the primary cervical cancer cells (R2=0.6516, P<0.001). In vitro, abundant miR-218 increased the radiosensitivity in cervical cancer cells (P<0.001 for HeLa, P=0.009 for SiHa, P=0.016 for C33A and P=0.01 for CaSki). Upregulation of miR-218 significantly enhanced the radiation-induced apoptosis, which was further enhanced by the combination of miR-218 overexpression and radiation In xenograft growth assay, combination of miR-218 overexpression and radiation notably induced cellular apoptosis and suppressed tumor growth. In conclusion, we demonstrated that miR-218 resensitized cervical cancer cells to radiation via promoting cellular apoptosis. Moreover, we proved that miR-218 as a potent predictor of radiosensitivity in cervical cancer, especially for those patients with loss of miR-218.

Yuan, Wang; Xiaoyun, Han; Haifeng, Qiu; Jing, Li; Weixu, Hu; Ruofan, Dong; Jinjin, Yu; Zongji, Shen

2014-01-01

25

Therapeutic and Radiosensitizing Effects of Armillaridin on Human Esophageal Cancer Cells  

PubMed Central

Background. Armillaridin (AM) is isolated from Armillaria mellea. We examined the anticancer activity and radiosensitizing effect on human esophageal cancer cells. Methods. Human squamous cell carcinoma (CE81T/VGH and TE-2) and adenocarcinoma (BE-3 and SKGT-4) cell lines were cultured. The MTT assay was used for cell viability. The cell cycle was analyzed using propidium iodide staining. Mitochondrial transmembrane potential was measured by DiOC6(3) staining. The colony formation assay was performed for estimation of the radiation surviving fraction. Human CE81T/VGH xenografts were established for evaluation of therapeutic activity in vivo. Results. AM inhibited the viability of four human esophageal cancer cell lines with an estimated concentration of 50% inhibition (IC50) which was 3.4–6.9??M. AM induced a hypoploid cell population and morphological alterations typical of apoptosis in cells. This apoptosis induction was accompanied by a reduction of mitochondrial transmembrane potential. AM accumulated cell cycle at G2/M phase and enhanced the radiosensitivity in CE81T/VGH cells. In vivo, AM inhibited the growth of CE81T/VGH xenografts without significant impact on body weight and white blood cell counts. Conclusion. Armillaridin could inhibit growth and enhance radiosensitivity of human esophageal cancer cells. There might be potential to integrate AM with radiotherapy for esophageal cancer treatment.

Chi, Chih-Wen; Chen, Chien-Chih; Chen, Yu-Jen

2013-01-01

26

Radiosensitization in human breast carcinoma cells by thymoquinone: role of cell cycle and apoptosis.  

PubMed

TQ (thymoquinone), the bioactive constituent of black seed (Nigella sativa), has been shown to inhibit the growth of various human cancers both in vitro and in vivo. This study reports the radiosensitizing effect of TQ on human breast carcinoma cells (MCF7 and T47D). TQ in combination with single dose of ionizing radiation (2.5 Gy) was found to exert supra-additive cytotoxic effects on both the carcinomas as measured by cell proliferation and colony-formation assays. Annexin V binding and FACS analysis revealed the role of enhanced apoptosis and cell cycle modulation in the mechanism of TQ-mediated radiosensitization, thus supporting TQ as an adjuvant for preclinical testing in cancer chemo-radiotherapy. PMID:21557727

Velho-Pereira, Reelma; Kumar, Amit; Pandey, Badri N; Jagtap, Aarti G; Mishra, Kaushala P

2011-10-01

27

Prostate-targeted radiosensitization via aptamer-shRNA chimeras in human tumor xenografts  

PubMed Central

Dose-escalated radiation therapy for localized prostate cancer (PCa) has a clear therapeutic benefit; however, escalated doses may also increase injury to noncancerous tissues. Radiosensitizing agents can improve ionizing radiation (IR) potency, but without targeted delivery, these agents will also sensitize surrounding normal tissues. Here we describe the development of prostate-targeted RNAi agents that selectively sensitized prostate-specific membrane antigen–positive (PSMA-positive) cells to IR. siRNA library screens identified DNA-activated protein kinase, catalytic polypeptide (DNAPK) as an ideal radiosensitization target. DNAPK shRNAs, delivered by PSMA-targeting RNA aptamers, selectively reduced DNAPK in PCa cells, xenografts, and human prostate tissues. Aptamer-targeted DNAPK shRNAs, combined with IR, dramatically and specifically enhanced PSMA-positive tumor response to IR. These findings support aptamer-shRNA chimeras as selective sensitizing agents for the improved treatment of high-risk localized PCa.

Ni, Xiaohua; Zhang, Yonggang; Ribas, Judit; Chowdhury, Wasim H.; Castanares, Mark; Zhang, Zhewei; Laiho, Marikki; DeWeese, Theodore L.; Lupold, Shawn E.

2011-01-01

28

Inhibition of Rho pathways induces radiosensitization and oxygenation in human glioblastoma xenografts.  

PubMed

We previously demonstrated in vitro that inhibiting the biological pathways of the small GTPase Rho radiosensitizes the human glioma U87 cell line. The aim of this study was to determine if Rho might be involved in the control of in vivo radiosensitivity altogether by controlling cellular radioresistance and by modifying tumor microenvironment. We demonstrate here that the in vivo induction of the dominant negative of Rho, RhoBN19, in U87 xenografts induces a significant decrease of tumor cell survival after irradiation more important than the one we previously observed in vitro. This in vivo increased effect of RhoBN19 expression is due to the improvement of the tumor oxygenation associated with a significant decrease of the vessel density and of the metalloproteinase 2 (MMP2) expression. Moreover, in vitro RhoBN19 expression in U87 cells leads to the inhibition of MMP2 activity. Our results demonstrate for the first time that inhibiting Rho pathways modifies the in vivo radiosensitivity of human glioma cells by controlling intrinsic radioresistance, hypoxia and angiogenesis. These data strongly suggest that Rho should be a major determinant of cellular resistance to ionizing radiation. PMID:14654782

Ader, Isabelle; Delmas, Caroline; Bonnet, Jacques; Rochaix, Philippe; Favre, Gilles; Toulas, Christine; Cohen-Jonathan-Moyal, Elizabeth

2003-12-01

29

Monoclonal antibodies as therapeutics in human malignancies.  

PubMed

Monoclonal antibodies (mAbs) are a proven effective therapeutic modality in human malignancy. Several mAbs are approved to targets critical in aberrant oncogenic signaling within tumors and their microenvironment. These targets include secreted ligands (e.g., VEGF and HGH), their receptors (e.g., HER2 and VEGFR2), cell surface counter receptors and their receptor-bound ligands (e.g., PD1 and PD1L, respectively). The ability to genetically engineer the structure and/or functions of mAbs has significantly improved their effectiveness. Furthermore, advances in gene expression profiling, proteomics, deep sequencing and deciphering of complex signaling networks have revealed novel therapeutic targets. We review target selection, approved indications and the rationale for mAb utilization in solid and hematologic malignancies. We also discuss novel mAbs in early- and late-phase clinical trials that are likely to change the natural history of disease and improve survival. The future challenge is to design mAb-based novel trial designs for diagnostics and therapeutics for human malignancies. PMID:24754592

Pandey, Manjari; Mahadevan, Daruka

2014-03-01

30

Histone deacetylase inhibitor-mediated radiosensitization of human cancer cells: class differences and the potential influence of p53.  

PubMed

Histone deacetylase inhibitors (HDI) are emerging as potentially useful components of the anticancer armamentarium and as useful tools to dissect mechanistic pathways. HDIs that globally inhibit histone deacetylases (HDAC) have radiosensitizing effects, but the relative contribution of specific HDAC classes remains unclear. Newly characterized HDIs are now available that preferentially inhibit specific HDAC classes, including SK7041 (inhibits class I HDACs) and splitomicin (inhibits class III HDACs). We investigated in human cancer cells the relative radiosensitizations that result from blocking specific HDAC classes. We found that trichostatin A (TSA; inhibitor of both class I and II HDACs) was the most effective radiosensitizer, followed by the class I inhibitor SK7041, whereas splitomicin (inhibitor of class III) had least effect. Interestingly, radiosensitization by TSA in cell lines expressing p53 was more pronounced than in isogenic lines lacking p53. Radiosensitization of cells expressing p53 by TSA was reduced by pifithrin-alpha, a small-molecule inhibitor of p53. In contrast, the radiosensitization by TSA of cells expressing low levels of p53 was enhanced by transfection of wild-type p53-expressing vector or pretreatment with leptomycin B, an inhibitor of nuclear export that increased intracellular levels of p53. These effects on radiosensitization were respectively muted or not seen in cells treated with SK7041 or splitomicin. To our knowledge, this may be among the first systematic investigations of the comparative anticancer effects of inhibiting specific classes of HDACs, with results suggesting differences in the degrees of radiosensitization, which in some cell lines may be influenced by p53 expression. PMID:16467109

Kim, In Ah; Shin, Jin Hee; Kim, Il Han; Kim, Jin Ho; Kim, Jae Sung; Wu, Hong Gyun; Chie, Eui Kyu; Ha, Sung Whan; Park, Charn Il; Kao, Gary D

2006-02-01

31

Inherent cellular radiosensitivity of human tumors of varying clinical curability.  

PubMed

It is well known that radiation therapy can be successfully used to cure or control some types of human tumors, while consistently failing in others. This has been ascribed to several factors including differences in the intrinsic sensitivity of the tumor cells and in their ability to recover from radiation damage. In this study, human tumor cells from an osteogenic sarcoma, a glioblastoma, and two medulloblastomas, as well as cells from human skin, were established in tissue culture, and the in vitrox x-ray survival and DNA repair parameters determined. No significant differences in either clonogenic survival or DNA strand rejoining ability could be detected among these human tumors or skin cells, despite the wide variability in their radiocurability in vivo. In addition, skin cell strains derived from patients exhibiting markedly sensitive or resistant skin reactions during fractionated radiotherapy showed no differences in survival characteristics from normal controls. It is therefore suggested that the wide range of radiocurabilities seen among various human tumors cannot be explained on the basis of inherent cellular factors responsible for the survival of tumor cells after x-irradiation. PMID:1069484

Weichselbaum, R R; Epstein, J; Little, J B; Kornblith, P

1976-12-01

32

Costunolide causes mitotic arrest and enhances radiosensitivity in human hepatocellular carcinoma cells  

Microsoft Academic Search

Purpose  This work aimed to investigate the effect of costunolide, a sesquiterpene lactone isolated from Michelia compressa, on cell cycle distribution and radiosensitivity of human hepatocellular carcinoma (HCC) cells.\\u000a \\u000a \\u000a \\u000a \\u000a Methods  The assessment used in this study included: cell viability assay, cell cycle analysis by DNA histogram, expression of phosphorylated\\u000a histone H3 (Ser 10) by flow cytometer, mitotic index by Liu's stain and

Chia-Yuan Liu; Hsun-Shuo Chang; Ih-Sheng Chen; Chih-Jen Chen; Ming-Ling Hsu; Shu-Ling Fu; Yu-Jen Chen

2011-01-01

33

HLA-G1 increases the radiosensitivity of human tumoral cells.  

PubMed

Different molecules regulate the response of tumoral tissues to ionizing radiation. The objective of this work was to determine if HLA-G1 expression modulates the radiosensitivity of human tumoral cell lines. To this end, human melanoma M8 and human erythroleukemia K562 cell lines, with their correspondent HLA-G1 negative and positive variants, were gamma irradiated and the survival frequency was determined by clonogenic assay. The survival fraction of HLA-G1 expressing cells was around 60% of HLA-G1 negative cells. The generation of acidic vesicular organelles was higher in HLA-G1 positive cells. Apoptosis levels showed statistically significant differences only in K562 cells, whereas the variation in G2/M cycle progression was only significant in M8 cells. In addition, irradiation diminished cell-surface HLA-G1 and increased soluble HLA-G1 levels. Soluble HLA-G1 has no influence on cell survival in any cell line. In summary, we could demonstrate that HLA-G1 confers higher radiosensitivity to HLA-G1 expressing cells. PMID:24487034

Gallegos, Cristina E; Michelin, Severino; Trasci, Sofía Baffa; Lobos, Elizabeth Aballay; Dubner, Diana; Carosella, Edgardo D

2014-02-01

34

Radiosensitivity in multidrug-resistant and cisplatin-resistant human carcinoma cell lines.  

PubMed

The radiosensitivity of a multidrug-resistant (MDR) clone and a cisplatin-resistant clone was compared with that of their parental chemosensitive cell lines. The LoVo cell line was derived from a human colon carcinoma, and LoVo-R was the MDR clone. The MDR phenotype is attributable to an increased drug efflux mediated by the P-glycoprotein and involves several classes of structurally unrelated drugs. The 2008 cell line was derived from a human ovary carcinoma and C13 was the cisplatin-resistant clone. Reduced cisplatin accumulation and elevated plasma membrane potential partially account for the drug resistance of C13 cells. The chemoresistance of LoVo-R and C13 cells was confirmed by cytotoxicity tests consisting of 24-hour paclitaxel and 1-hour cisplatin incubation, respectively. The radiosensitivity was evaluated by a clonogenic test. The dose-reducing cell survival fraction from 1 to 0.37 (D(0)), the quasi-threshold dose (Dq), and the survival fraction (SF) after 2 or 4 Gy were determined for each cell line. D(0), Dq, and SF(2) were 1.3 +/- 0.4 Gy, 2.1 +/- 0.6 Gy, and 43 +/- 4% for the LoVo cell line and 1.0 +/- 0.2 Gy, 1.7 +/- 0.4 Gy, and 45 +/- 8%, respectively, for the LoVo-R cell line. D(0), Dq, and SF(4) were 1.7 +/- 0.3 Gy, 3.1 +/- 0.4 Gy, and 43 +/- 12% for 2008 cells and 2.6 +/- 0.5 Gy, 4.3 +/- 0.6 Gy, and 53 +/- 11%, respectively for C13 cells. No significant differences were found between LoVo and LoVo-R cells, whereas C13 cells showed a significantly greater D(0,) Dq, and SF(4) than 2008 cells (p <0.05). Incubation of 2008 and C13 cells with subcytotoxic buthionine (BSO) before and after irradiation partially restored C13 radiosensitivity. In fact, D(0) dropped from 2.8 +/- 0.1 to 2.0 +/- 0.3 Gy in C13 cells with and without BSO, whereas it was 1.9 +/- 0.2 Gy in 2008 cells in the absence and presence of BSO. The total glutathione content (GSH) of C13 cells was 1.5-fold higher than that of 2008 cells. BSO treatment caused a partial depletion of GSH in 2008 and C13 cells, but their radiosensitivity did not change accordingly. PMID:12902902

Gigante, Marco; Toffoli, Giuseppe; Bertola, Antonella; Biscontin, Gabriella; Dassie, Andrea; Zanelli, Giuseppe D; Zanin, Enzo; Trovò, Mauro G; Muzzio, Pier Carlo

2003-08-01

35

Adenoviral transduction of human acid sphingomyelinase into neo-angiogenic endothelium radiosensitizes tumor cure.  

PubMed

These studies define a new mechanism-based approach to radiosensitize tumor cure by single dose radiotherapy (SDRT). Published evidence indicates that SDRT induces acute microvascular endothelial apoptosis initiated via acid sphingomyelinase (ASMase) translocation to the external plasma membrane. Ensuing microvascular damage regulates radiation lethality of tumor stem cell clonogens to effect tumor cure. Based on this biology, we engineered an ASMase-producing vector consisting of a modified pre-proendothelin-1 promoter, PPE1(3x), and a hypoxia-inducible dual-binding HIF-2?-Ets-1 enhancer element upstream of the asmase gene, inserted into a replication-deficient adenovirus yielding the vector Ad5H2E-PPE1(3x)-ASMase. This vector confers ASMase over-expression in cycling angiogenic endothelium in vitro and within tumors in vivo, with no detectable enhancement in endothelium of normal tissues that exhibit a minute fraction of cycling cells or in non-endothelial tumor or normal tissue cells. Intravenous pretreatment with Ad5H2E-PPE1(3x)-ASMase markedly increases SDRT cure of inherently radiosensitive MCA/129 fibrosarcomas, and converts radiation-incurable B16 melanomas into biopsy-proven tumor cures. In contrast, Ad5H2E-PPE1(3x)-ASMase treatment did not impact radiation damage to small intestinal crypts as non-dividing small intestinal microvessels did not overexpress ASMase and were not radiosensitized. We posit that combination of genetic up-regulation of tumor microvascular ASMase and SDRT provides therapeutic options for currently radiation-incurable human tumors. PMID:23936314

Stancevic, Branka; Varda-Bloom, Nira; Cheng, Jin; Fuller, John D; Rotolo, Jimmy A; García-Barros, Mónica; Feldman, Regina; Rao, Shyam; Weichselbaum, Ralph R; Harats, Dror; Haimovitz-Friedman, Adriana; Fuks, Zvi; Sadelain, Michel; Kolesnick, Richard

2013-01-01

36

Adenoviral Transduction of Human Acid Sphingomyelinase into Neo-Angiogenic Endothelium Radiosensitizes Tumor Cure  

PubMed Central

These studies define a new mechanism-based approach to radiosensitize tumor cure by single dose radiotherapy (SDRT). Published evidence indicates that SDRT induces acute microvascular endothelial apoptosis initiated via acid sphingomyelinase (ASMase) translocation to the external plasma membrane. Ensuing microvascular damage regulates radiation lethality of tumor stem cell clonogens to effect tumor cure. Based on this biology, we engineered an ASMase-producing vector consisting of a modified pre-proendothelin-1 promoter, PPE1(3x), and a hypoxia-inducible dual-binding HIF-2?-Ets-1 enhancer element upstream of the asmase gene, inserted into a replication-deficient adenovirus yielding the vector Ad5H2E-PPE1(3x)-ASMase. This vector confers ASMase over-expression in cycling angiogenic endothelium in vitro and within tumors in vivo, with no detectable enhancement in endothelium of normal tissues that exhibit a minute fraction of cycling cells or in non-endothelial tumor or normal tissue cells. Intravenous pretreatment with Ad5H2E-PPE1(3x)-ASMase markedly increases SDRT cure of inherently radiosensitive MCA/129 fibrosarcomas, and converts radiation-incurable B16 melanomas into biopsy-proven tumor cures. In contrast, Ad5H2E-PPE1(3x)-ASMase treatment did not impact radiation damage to small intestinal crypts as non-dividing small intestinal microvessels did not overexpress ASMase and were not radiosensitized. We posit that combination of genetic up-regulation of tumor microvascular ASMase and SDRT provides therapeutic options for currently radiation-incurable human tumors.

Fuller, John D.; Rotolo, Jimmy A.; Garcia-Barros, Monica; Feldman, Regina; Rao, Shyam; Weichselbaum, Ralph R.; Harats, Dror; Haimovitz-Friedman, Adriana; Fuks, Zvi; Sadelain, Michel; Kolesnick, Richard

2013-01-01

37

Guggulsterone-Mediated Enhancement of Radiosensitivity in Human Tumor Cell Lines  

PubMed Central

Purpose: To observe the effect of guggulsterone (GS) on the radiation response in human cancer cell lines. Materials and methods: The radiation response of cancer cells treated with GS was observed by cell survival studies, cell growth assay, NF-?B activity assay, western blotting of some key growth promoting receptors, the DNA repair protein ?H2AX, and flow cytometry for DNA analyses. Results: GS inhibited radiation induced NF-?B activation and enhanced radiosensitivity in the pancreatic cell line, PC-Sw. It reduced both cell cycle movement and cell growth. GS reduced ER? protein in MCF7 cells and IGF1-R? protein in colon cancer cells and pancreatic cancer cells and inhibited DNA double strand break (DSB) repair following radiation. Conclusion: GS induced radiation sensitization may be due to several different mechanisms including the inhibition of NF-?B activation and reductions in IGF1-R?. In addition, GS induced ?H2AX formation, primarily in the S-phase, indicates that DNA DSB's in the S-phase may be another reason for GS induced radiosensitivity. ER? down-regulation in response to GS suggests that it can be of potential use in the treatment of estrogen positive tumors that are resistant to tamoxifen.

Choudhuri, Rajani; DeGraff, William; Gamson, Janet; Mitchell, James B.; Cook, John A.

2011-01-01

38

Replication-Dependent Radiosensitization of Human Glioma Cells by Inhibition of Poly(ADP-Ribose) Polymerase: Mechanisms and Therapeutic Potential  

SciTech Connect

Purpose: Current treatments for glioblastoma multiforme are inadequate and limited by the radiation sensitivity of normal brain. Because glioblastoma multiforme are rapidly proliferating tumors within nondividing normal tissue, the therapeutic ratio might be enhanced by combining radiotherapy with a replication-specific radiosensitizer. KU-0059436 (AZD2281) is a potent and nontoxic inhibitor of poly(ADP-ribose) polymerase-1 (PARP-1) undergoing a Phase II clinical trial as a single agent. Methods and Materials: Based on previous observations that the radiosensitizing effects of PARP inhibition are more pronounced in dividing cells, we investigated the mechanisms underlying radiosensitization of human glioma cells by KU-0059436, evaluating the replication dependence of this effect and its therapeutic potential. Results: KU-0059436 increased the radiosensitivity of four human glioma cell lines (T98G, U373-MG, UVW, and U87-MG). Radiosensitization was enhanced in populations synchronized in S phase and abrogated by concomitant exposure to aphidicolin. Sensitization was further enhanced when the inhibitor was combined with a fractionated radiation schedule. KU-0059436 delayed repair of radiation-induced DNA breaks and was associated with a replication-dependent increase in {gamma}H2AX and Rad51 foci. Conclusion: The results of our study have shown that KU-0059436 increases radiosensitivity in a replication-dependent manner that is enhanced by fractionation. A mechanism is proposed whereby PARP inhibition increases the incidence of collapsed replication forks after ionizing radiation, generating persistent DNA double-strand breaks. These observations indicate that KU-0059436 is likely to enhance the therapeutic ratio achieved by radiotherapy in the treatment of glioblastoma multiforme. A Phase I clinical trial is in development.

Dungey, Fiona A.; Loeser, Dana A. [Genome Damage and Stability Centre, University of Sussex, Brighton (United Kingdom); Chalmers, Anthony J. [Genome Damage and Stability Centre, University of Sussex, Brighton (United Kingdom); Brighton and Sussex Medical School, University of Sussex, Brighton (United Kingdom)], E-mail: a.j.chalmers@sussex.ac.uk

2008-11-15

39

Niraparib (MK-4827), a novel poly(ADP-Ribose) polymerase inhibitor, radiosensitizes human lung and breast cancer cells.  

PubMed

The aim of this study was to assess niraparib (MK-4827), a novel poly(ADP-Ribose) polymerase (PARP) inhibitor, for its ability to radiosensitize human tumor cells. Human tumor cells derived from lung, breast and prostate cancers were tested for radiosensitization by niraparib using clonogenic survival assays. Both p53 wild-type and p53-defective lines were included. The ability of niraparib to alter the repair of radiation-induced DNA double strand breaks (DSBs) was determined using detection of ?-H2AX foci and RAD51 foci. Clonogenic survival analyses indicated that micromolar concentrations of niraparib radiosensitized tumor cell lines derived from lung, breast, and prostate cancers independently of their p53 status but not cell lines derived from normal tissues. Niraparib also sensitized tumor cells to H2O2 and converted H2O2-induced single strand breaks (SSBs) into DSBs during DNA replication. These results indicate that human tumor cells are significantly radiosensitized by the potent and selective PARP-1 inhibitor, niraparib, in the in vitro setting. The mechanism of this effect appears to involve a conversion of sublethal SSBs into lethal DSBs during DNA replication due to the inhibition of base excision repair by the drug. Taken together, our findings strongly support the clinical evaluation of niraparib in combination with radiation. PMID:24970803

Bridges, Kathleen A; Toniatti, Carlo; Buser, Carolyn A; Liu, Huifeng; Buchholz, Thomas A; Meyn, Raymond E

2014-07-15

40

HIF-1? inhibition by siRNA or chetomin in human malignant glioma cells: effects on hypoxic radioresistance and monitoring via CA9 expression  

PubMed Central

Background Hypoxia induces activation of the HIF-1 pathway and is an essential characteristic of malignant gliomas. Hypoxia has been linked to tumor progression, therapy resistance and poor prognosis. However, little is known about the impact of HIF-1? inhibition on radioresistance of malignant glioma. Methods In this study, we investigated the effects of the inhibition of HIF-1? on cell survival and radiosensitivity in U251MG and U343MG glioma cells, using two different strategies. HIF-1? inhibition was achieved by siRNA targeting of HIF-1? or via chetomin, a disruptor of interactions between HIF-1? and p300. The inhibition of the HIF-1 pathway was monitored by quantitative real-time PCR and Western blot analyses of the expression levels of HIF-1? and CA9. CA9 expression was investigated as a potential indicator of the efficacy of HIF-1 inhibition and the resulting radiosensitivity of malignant glioma cell lines was determined by clonogenic assay after irradiation under normoxic (2-10 Gy) or hypoxic (2-15 Gy) conditions. Results Although siRNA and chetomin show distinct modes of action, both attenuated the hypoxia-induced radioresistance of malignant glioma cell lines U251MG (DMF10: 1.35 and 1.18) and U343MG (DMF10: 1.78 and 1.48). However, siRNA and chetomin showed diverse effects on radiosensitivity under normoxic conditions in U251MG (DMF10: 0.86 and 1.35) and U343MG (DMF10: 1.33 and 1.02) cells. Conclusions Results from this in vitro study suggest that inhibition of HIF-1? is a promising strategy to sensitize human malignant gliomas to radiotherapy and that CA9 could serve as an indicator of effective HIF-1-related radiosensitization.

2010-01-01

41

Modulation of IdUrd-DNA incorporation and radiosensitization in human bladder carcinoma cells  

SciTech Connect

5' Amino-5'-deoxythymidine (5'-AdThd) has been demonstrated previously to antagonize dTTP-mediated feedback inhibition of purified thymidine kinase from 647V, a human bladder cancer cell line. Low concentrations of 5'-AdThd (3-30 microM) have also been shown to stimulate cellular uptake of iododeoxyuridine (IdUrd) in 647V cells at clinically relevant IdUrd concentrations (2 microM). We report that the combination of 30 microM 5'-AdThd plus 2 microM IdUrd results in a significant increase of IdUrd replacement of thymidine (dThd) (18%) in the DNA of 647V cells over that obtained by exposure to 2 microM IdUrd alone (7.9%). However, increasing the 5'-AdThd concentration to 300 microM inhibited the incorporation of IdUrd into DNA (3%). IdUrd-induced radiosensitization of 647V cells, as measured by clonogenic survival, was enhanced by coincubation with 30 microM 5'-AdThd, while 300 microM 5'-AdThd reduced the IdUrd radiosensitization. Additionally, radiation-induced single strand break generation when IdUrd was incorporated into 647V DNA, as measured by rapid alkaline elution, was also enhanced by coincubation with 30 microM 5'-AdThd, while 300 microM 5'-AdThd resulted in a decrease in the number of single strand breaks produced. In T24, another bladder cancer cell line, and SV-HUC-TT1, a tumorigenic cell line derived from SV-HUC, 3-10 microM 5'-AdThd was also able to enhance IdUrd replacement of dThd in DNA. However, no stimulation of dThd replacement by 5'-AdThd occurred in SV-HUC, a prototypic normal bladder urothelial cell line. Since 5'-AdThd is not a substrate for mammalian thymidine kinase and has little or no cytotoxicity in vitro and in vivo, it may be a selective modulator of IdUrd radiosensitization of human bladder carcinoma and should be tested in vivo.

Kunugi, K.A.; Vazquez-Padua, M.A.; Miller, E.M.; Kinsella, T.J. (Univ. of Wisconsin, Madison (USA))

1990-08-15

42

Autotaxin Inhibition with PF-8380 Enhances the Radiosensitivity of Human and Murine Glioblastoma Cell Lines  

PubMed Central

Purpose: Glioblastoma multiforme (GBM) is an aggressive primary brain tumor that is radio-resistant and recurs despite aggressive surgery, chemo, and radiotherapy. Autotaxin (ATX) is over expressed in various cancers including GBM and is implicated in tumor progression, invasion, and angiogenesis. Using the ATX specific inhibitor, PF-8380, we studied ATX as a potential target to enhance radiosensitivity in GBM. Methods and Materials: Mouse GL261 and Human U87-MG cells were used as GBM cell models. Clonogenic survival assays and tumor transwell invasion assays were performed using PF-8380 to evaluate role of ATX in survival and invasion. Radiation dependent activation of Akt was analyzed by immunoblotting. Tumor induced angiogenesis was studied using the dorsal skin fold model in GL261. Heterotopic mouse GL261 tumors were used to evaluate the efficacy of PF-8380 as a radiosensitizer. Results: Pre-treatment of GL261 and U87-MG cells with 1??M PF-8380 followed by 4?Gy irradiation resulted in decreased clonogenic survival, decreased migration (33% in GL261; P?=?0.002 and 17.9% in U87-MG; P?=?0.012), decreased invasion (35.6% in GL261; P?=?0.0037 and 31.8% in U87-MG; P?=?0.002), and attenuated radiation-induced Akt phosphorylation. In the tumor window model, inhibition of ATX abrogated radiation induced tumor neovascularization (65%; P?=?0.011). In a heterotopic mouse GL261 tumors untreated mice took 11.2?days to reach a tumor volume of 7000?mm3, however combination of PF-8380 (10?mg/kg) with irradiation (five fractions of 2?Gy) took more than 32?days to reach a tumor volume of 7000?mm3. Conclusion: Inhibition of ATX by PF-8380 led to decreased invasion and enhanced radiosensitization of GBM cells. Radiation-induced activation of Akt was abrogated by inhibition of ATX. Furthermore, inhibition of ATX led to diminished tumor vascularity and delayed tumor growth. These results suggest that inhibition of ATX may ameliorate GBM response to radiotherapy.

Bhave, Sandeep R.; Dadey, David Y. A.; Karvas, Rowan M.; Ferraro, Daniel J.; Kotipatruni, Rama P.; Jaboin, Jerry J.; Hallahan, Andrew N.; DeWees, Todd A.; Linkous, Amanda G.; Hallahan, Dennis E.; Thotala, Dinesh

2013-01-01

43

Autotaxin Inhibition with PF-8380 Enhances the Radiosensitivity of Human and Murine Glioblastoma Cell Lines.  

PubMed

Purpose: Glioblastoma multiforme (GBM) is an aggressive primary brain tumor that is radio-resistant and recurs despite aggressive surgery, chemo, and radiotherapy. Autotaxin (ATX) is over expressed in various cancers including GBM and is implicated in tumor progression, invasion, and angiogenesis. Using the ATX specific inhibitor, PF-8380, we studied ATX as a potential target to enhance radiosensitivity in GBM. Methods and Materials: Mouse GL261 and Human U87-MG cells were used as GBM cell models. Clonogenic survival assays and tumor transwell invasion assays were performed using PF-8380 to evaluate role of ATX in survival and invasion. Radiation dependent activation of Akt was analyzed by immunoblotting. Tumor induced angiogenesis was studied using the dorsal skin fold model in GL261. Heterotopic mouse GL261 tumors were used to evaluate the efficacy of PF-8380 as a radiosensitizer. Results: Pre-treatment of GL261 and U87-MG cells with 1??M PF-8380 followed by 4?Gy irradiation resulted in decreased clonogenic survival, decreased migration (33% in GL261; P?=?0.002 and 17.9% in U87-MG; P?=?0.012), decreased invasion (35.6% in GL261; P?=?0.0037 and 31.8% in U87-MG; P?=?0.002), and attenuated radiation-induced Akt phosphorylation. In the tumor window model, inhibition of ATX abrogated radiation induced tumor neovascularization (65%; P?=?0.011). In a heterotopic mouse GL261 tumors untreated mice took 11.2?days to reach a tumor volume of 7000?mm(3), however combination of PF-8380 (10?mg/kg) with irradiation (five fractions of 2?Gy) took more than 32?days to reach a tumor volume of 7000?mm(3). Conclusion: Inhibition of ATX by PF-8380 led to decreased invasion and enhanced radiosensitization of GBM cells. Radiation-induced activation of Akt was abrogated by inhibition of ATX. Furthermore, inhibition of ATX led to diminished tumor vascularity and delayed tumor growth. These results suggest that inhibition of ATX may ameliorate GBM response to radiotherapy. PMID:24062988

Bhave, Sandeep R; Dadey, David Y A; Karvas, Rowan M; Ferraro, Daniel J; Kotipatruni, Rama P; Jaboin, Jerry J; Hallahan, Andrew N; Dewees, Todd A; Linkous, Amanda G; Hallahan, Dennis E; Thotala, Dinesh

2013-01-01

44

Radiosensitization of Human Leukemic HL-60 Cells by ATR Kinase Inhibitor (VE-821): Phosphoproteomic Analysis.  

PubMed

DNA damaging agents such as ionizing radiation or chemotherapy are frequently used in oncology. DNA damage response (DDR)-triggered by radiation-induced double strand breaks-is orchestrated mainly by three Phosphatidylinositol 3-kinase-related kinases (PIKKs): Ataxia teleangiectasia mutated (ATM), DNA-dependent protein kinase (DNA-PK) and ATM and Rad3-related kinase (ATR). Their activation promotes cell-cycle arrest and facilitates DNA damage repair, resulting in radioresistance. Recently developed specific ATR inhibitor, VE-821 (3-amino-6-(4-(methylsulfonyl)phenyl)-N-phenylpyrazine-2-carboxamide), has been reported to have a significant radio- and chemo-sensitizing effect delimited to cancer cells (largely p53-deficient) without affecting normal cells. In this study, we employed SILAC-based quantitative phosphoproteomics to describe the mechanism of the radiosensitizing effect of VE-821 in human promyelocytic leukemic cells HL-60 (p53-negative). Hydrophilic interaction liquid chromatography (HILIC)-prefractionation with TiO2-enrichment and nano-liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis revealed 9834 phosphorylation sites. Proteins with differentially up-/down-regulated phosphorylation were mostly localized in the nucleus and were involved in cellular processes such as DDR, all phases of the cell cycle, and cell division. Moreover, sequence motif analysis revealed significant changes in the activities of kinases involved in these processes. Taken together, our data indicates that ATR kinase has multiple roles in response to DNA damage throughout the cell cycle and that its inhibitor VE-821 is a potent radiosensitizing agent for p53-negative HL-60 cells. PMID:25003641

Salovská, Barbora; Fabrik, Ivo; Durišová, Kamila; Link, Marek; Vávrová, Ji?ina; Rezá?ová, Martina; Tichý, Aleš

2014-01-01

45

Combined EGFR and Autophagy Modulation Impairs Cell Migration and Enhances Radiosensitivity in Human Glioblastoma Cells.  

PubMed

Glioblastoma (GBM) remains the most aggressive and lethal brain tumor due to its molecular heterogeneity and high motility and invasion capabilities of its cells, resulting in high resistance to current standard treatments (surgery, followed by ionizing radiation combined with Temozolomide chemotherapy administration). Locus amplification, gene overexpression, and genetic mutations of epidermal growth factor receptor (EGFR) are hallmarks of GBM that can ectopically activate downstream signaling oncogenic cascades such as PI3K/Akt/mTOR pathway. Importantly, alteration of this pathway, involved also in the regulation of autophagy process, can improve radioresistance in GBM cells, thus promoting the aggressive phenotype of this tumor. In this work, the endogenous EGFR expression profile and autophagy were modulated to increase radiosensitivity behavior of human T98G and U373MG GBM cells. Our results primarily indicated that EGFR interfering induced radiosensitivity according to a decrease of the clonogenic capability of the investigated cells, and an effective reduction of the in vitro migratory features. Moreover, EGFR interfering resulted in an increase of Temozolomide (TMZ) cytotoxicity in T98G TMZ-resistant cells. In order to elucidate the involvement of the autophagy process as pro-death or pro-survival role in cells subjected to EGFR interfering, the key autophagic gene ATG7 was silenced, thereby producing a transient block of the autophagy process. This autophagy inhibition rescued clonogenic capability of irradiated and EGFR-silenced T98G cells, suggesting a pro-death autophagy contribution. To further confirm the functional interplay between EGFR and autophagy pathways, Rapamycin-mediated autophagy induction during EGFR modulation promoted further impairment of irradiated cells, in terms of clonogenic and migration capabilities. Taken together, these results might suggest a novel combined EGFR-autophagy modulation strategy, to overcome intrinsic GBM radioresistance, thus improving the efficacy of standard treatments. J. Cell. Physiol. 229: 1863-1873, 2014. © 2014 Wiley Periodicals, Inc. PMID:24691646

Palumbo, Silvia; Tini, Paolo; Toscano, Marzia; Allavena, Giulia; Angeletti, Francesca; Manai, Federico; Miracco, Clelia; Comincini, Sergio; Pirtoli, Luigi

2014-11-01

46

Radiosensitization of Oropharyngeal Squamous Cell Carcinoma Cells by Human Papillomavirus 16 Oncoprotein E6*I  

SciTech Connect

Purpose: Patients with oropharyngeal squamous cell carcinoma (OSCC) whose disease is associated with high-risk human papillomavirus (HPV) infection have a significantly better outcome than those with HPV-negative disease, but the reasons for the better outcome are not known. We postulated that they might relate to an ability of HPV proteins to confer a better response to radiotherapy, a commonly used treatment for OSCC. Methods and Materials: We stably expressed the specific splicing-derived isoforms, E6*I and E6*II, or the entire E6 open reading frame (E6total), which gives rise to both full length and E6*I isoforms, in OSCC cell lines. Radiation resistance was measured in clonogenicity assays, p53 activity was measured using transfected reporter genes, and flow cytometry was used to analyze cell cycle and apoptosis. Results: E6*I and E6total sensitized the OSCC cells to irradiation, E6*I giving the greatest degree of radiosensitization (approximately eightfold lower surviving cell fraction at 10 Gy), whereas E6*II had no effect. In contrast to radiosensitivity, E6*I was a weaker inhibitor than E6total of tumor suppressor p53 transactivator activity in the same cells. Flow cytometric analyses showed that irradiated E6*I expressing cells had a much higher G2M:G1 ratio than control cells, indicating that, after G2, cells were diverted from the cell cycle to programmed cell death. Conclusion: This study supports a role for E6*I in the enhanced responsiveness of HPV-positive oropharyngeal carcinomas to p53-independent radiation-induced death.

Pang, Ervinna [Sydney Head and Neck Cancer Institute, Sydney Cancer Centre, Royal Prince Alfred Hospital, NSW (Australia); Discipline of Infectious Diseases and Immunology, University of Sydney, NSW (Australia); Delic, Naomi C. [Sydney Head and Neck Cancer Institute, Sydney Cancer Centre, Royal Prince Alfred Hospital, NSW (Australia); Discipline of Dermatology, University of Sydney, NSW (Australia); Hong, Angela; Zhang Mei [Sydney Head and Neck Cancer Institute, Sydney Cancer Centre, Royal Prince Alfred Hospital, NSW (Australia); Department of Radiation Oncology, Royal Prince Alfred Hospital, NSW (Australia); Rose, Barbara R. [Sydney Head and Neck Cancer Institute, Sydney Cancer Centre, Royal Prince Alfred Hospital, NSW (Australia); Discipline of Infectious Diseases and Immunology, University of Sydney, NSW (Australia); Lyons, J. Guy, E-mail: guy.lyons@sydney.edu.a [Sydney Head and Neck Cancer Institute, Sydney Cancer Centre, Royal Prince Alfred Hospital, NSW (Australia); Discipline of Dermatology, University of Sydney, NSW (Australia)

2011-03-01

47

Hypoxia-targeted triple suicide gene therapy radiosensitizes human colorectal cancer cells.  

PubMed

The hypoxic microenvironment, an important feature of human solid tumors but absent in normal tissue, may provide an opportunity for cancer-specific gene therapy. The purpose of the present study was to investigate whether hypoxia-driven triple suicide gene TK/CD/UPRT expression enhances cytotoxicity to ganciclovir (GCV) and 5-fluorocytosine (5-FC), and sensitizes human colorectal cancer to radiation in vitro and in vivo. Stable transfectant of human colorectal HCT8 cells was established which expressed hypoxia-inducible vectors (HRE-TK/eGFP and HRE-CD/UPRT/mDsRed). Hypoxia-induced expression/function of TK, CD and UPRT was verified by western blot analysis, flow cytometry, fluorescent microscopy and cytotoxicity assay of GCV and 5-FC. Significant radiosensitization effects were detected after 5-FC and GCV treatments under hypoxic conditions. In the tumor xenografts, the distribution of TK/eGFP and CD/UPRT/mDsRed expression visualized with fluorescence microscopy was co-localized with the hypoxia marker pimonidazole positive staining cells. Furthermore, administration of 5-FC and GCV in mice in combination with local irradiation resulted in tumor regression, as compared with prodrug or radiation treatments alone. Our data suggest that the hypoxia-inducible TK/GCV+CDUPRT/5-FC triple suicide gene therapy may have the ability to specifically target hypoxic cancer cells and significantly improve the tumor control in combination with radiotherapy. PMID:24912473

Hsiao, Hung Tsung; Xing, Ligang; Deng, Xuelong; Sun, Xiaorong; Ling, C Clifton; Li, Gloria C

2014-08-01

48

Hypoxia-targeted triple suicide gene therapy radiosensitizes human colorectal cancer cells  

PubMed Central

The hypoxic microenvironment, an important feature of human solid tumors but absent in normal tissue, may provide an opportunity for cancer-specific gene therapy. The purpose of the present study was to investigate whether hypoxia-driven triple suicide gene TK/CD/UPRT expression enhances cytotoxicity to ganciclovir (GCV) and 5-fluorocytosine (5-FC), and sensitizes human colorectal cancer to radiation in vitro and in vivo. Stable transfectant of human colorectal HCT8 cells was established which expressed hypoxia-inducible vectors (HRE-TK/eGFP and HRE-CD/UPRT/mDsRed). Hypoxia-induced expression/function of TK, CD and UPRT was verified by western blot analysis, flow cytometry, fluorescent microscopy and cytotoxicity assay of GCV and 5-FC. Significant radiosensitization effects were detected after 5-FC and GCV treatments under hypoxic conditions. In the tumor xenografts, the distribution of TK/eGFP and CD/UPRT/mDsRed expression visualized with fluorescence microscopy was co-localized with the hypoxia marker pimonidazole positive staining cells. Furthermore, administration of 5-FC and GCV in mice in combination with local irradiation resulted in tumor regression, as compared with prodrug or radiation treatments alone. Our data suggest that the hypoxia-inducible TK/GCV+CDUPRT/5-FC triple suicide gene therapy may have the ability to specifically target hypoxic cancer cells and significantly improve the tumor control in combination with radiotherapy.

HSIAO, HUNG TSUNG; XING, LIGANG; DENG, XUELONG; SUN, XIAORONG; LING, C. CLIFTON; LI, GLORIA C.

2014-01-01

49

Glycerol restores p53-dependent radiosensitivity of human head and neck cancer cells bearing mutant p53  

PubMed Central

Mutation or inactivation of p53 is known to be present in approximately 50% of human cancers. We propose here a novel strategy for overcoming this problem in mutant p53-targeting cancer therapies. We examined the restoration of radiation-induced p53-dependent apoptosis by a chemical chaperone (glycerol) in human head and neck cancer cells (SAS cells, showing wild-type p53 phenotype). SAS cells transfected with mutant p53 (SAS/m p53) showed radioresistance compared with SAS cells (SAS/ neo) transfected with neo vector as a control, but became radiosensitive when pre-treated with glycerol before X-ray irradiation. Apoptosis in the SAS/m p53 cells was induced by X-rays with glycerol pre-treatment, but not without glycerol pre-treatment, whereas apoptosis in the SAS/ neo cells was induced in both cases. Gel mobility-shift assays showed that after X-ray irradiation combined with glycerol pre-treatment, mp53 was able to bind to the sequence-specific region upstream of the bax gene regulating apoptosis. These results suggest that glycerol is effective in inducing a conformational change of p53 and restoring normal function to mp53, leading to enhanced radiosensitivity through the induction of apoptosis. This novel tool for enhancement of radiosensitivity in cancer cells bearing mp53 may be useful for p53-targeted radiotherapy. © 2000 Cancer Research Campaign http://www.bjcancer.com

Ohnishi, K; Ota, I; Takahashi, A; Ohnishi, T

2000-01-01

50

The radiosensitivity of human neuroblastoma cells estimated from regrowth curves of multicellular tumour spheroids.  

PubMed

Multicellular tumour spheroids may provide a suitable in-vitro model for micrometastases in vivo. In this paper, the results are reported of experimental studies on the radiation response of two lines of spheroids derived from human neuroblastoma. Spheroids of approximately 200-250 microM mean diameter were exposed to graded doses of X rays (50-350 cGy) and, following a static or regression phase, regrew at rates which approximated those of unirradiated spheroids. Clonogenic surviving fraction was estimated, at each dose level, by extrapolation of the regrowth curve to zero dose. It is proposed that this procedure is more suitable for regrowth curves of spheroids than in-vivo tumours, because of the absence in vitro of complicating factors which occur only in vivo. By this means, survival curves were deduced and were found (for both cell lines) to be almost exponential in form, with little indication of capacity for accumulation of sublethal damage (multitarget parameters: DQ values: 17 and 25 cGy; Do values: 104 and 81 cGy respectively). These results contribute to the evidence for high radiosensitivity of neuroblastoma cells in vitro and provide a rationale for the use of hyperfractionation in the clinical treatment of neuroblastoma by radiotherapy. PMID:4016498

Wheldon, T E; Livingstone, A; Wilson, L; O'Donoghue, J; Gregor, A

1985-07-01

51

Infrared absorption spectra of human malignant tumor tissues  

NASA Astrophysics Data System (ADS)

We used infrared spectroscopy methods to study the molecular structure of tissues from human organs removed during surgery. The IR spectra of the surgical material from breast, thyroid, and lung are compared with data from histological examination. We show that in malignant neoplasms, a change occurs in the hydrogen bonds of protein macromolecules found in the tissue of the studied organs. We identify the spectral signs of malignant pathology.

Skornyakov, I. V.; Tolstorozhev, G. B.; Butra, V. A.

2008-05-01

52

Effect of restoration of retinoblastoma gene function on the radiosensitivity of cells of human tumor cell lines  

SciTech Connect

To assess the role of expression of the retinoblastoma (RB) gene on the sensitivity of cells to the cytotoxic effects of ionizing radiation, we transfected a normal RB gene into cells of RB{sup +} and RB{sup {minus}} osteosarcoma cell lines and an RB{sup {minus}} prostate carcinoma line and studied the radiosensitivity of the cells before and after transfection. Four transfected clones were isolated from the two RB{sup {minus}} tumor cell lines that expressed the product of the transfected normal RB gene and contained no mutations in the pocket and C-terminal regions by sequencing. A small increase in radiosensitivity was observed in cell lines transfected with the pDOL plasmid vector alone, containing the neo gene and a long terminal repeat (LTR) promoter. However, no significant change in radiosensitivity occurred in transfected cells expressing the normal RB gene compared to controls transfected with an RB{sup {minus}} plasmid. Based on this and other information, we conclude that RB gene function is not involved in the response of these human tumor cells to the cytotoxic effects of radiation. 38 refs., 5 figs., 4 tabs.

Tsang, N.M.; Little, J.B. [Harvard School of Public Health, Boston, MA (United States)

1994-11-01

53

[The effect of low-dose irradiation and of age on the in vitro radiosensitivity of human lymphocytes].  

PubMed

The effect of low-dose irradiation and of age on the radiosensitivity of human lymphocytes was studies in two groups: control (67 people) and exposed to uncontrolled low-dose irradiation in past (165 people). Radiosensitivity of lymphocytes was estimated by the level of chromosome aberrations induced in vitro by gamma-radiation Cs137 at the dose 1.5 Gy. In exposed children the frequency of induced chromosome aberrations was higher and in the exposed adults--lower in comparison to the coresponding controls. To investigate an age response of the number of chromosome aberrations three statistical approaches were used: the correlation analysis of individual data, the correlation analysis of means for 10-years intervals, the comparison of 3 age groups. In control group no significant alteration in the level of induced chromosome aberrations with age was found. However the significant negative correlation between these two parameters was revealed in exposed group, which likely is due to the opposite direction of differences in radiosensitivity of exposed children and adults from the corresponding controls. PMID:18666646

Liubimova, N E; Vorobtsova, I E

2008-01-01

54

Activation of EDTA-resistant Gelatinases in Malignant Human Tumors  

PubMed Central

Among the many proteases associated with human cancer, seprase or fibroblast activation protein alpha (FAP-?)1, a type II transmembrane glycoprotein, has two types of EDTA-resistant protease activities: dipeptidyl peptidase (DP) and a 170-kDa gelatinase activity. To test if activation of gelatinases associated with seprase could be involved in malignant tumors, we used a mammalian expression system to generate a soluble recombinant seprase (r-seprase). In the presence of putative EDTA-sensitive activators, r-seprase was converted into 70- to 50-kDa shortened forms of seprase (s-seprase), which exhibited a 7-fold increase in gelatinase activity while levels of DP activity remained unchanged. In malignant human tumors, seprase is expressed predominantly in tumor cells as shown by in situ hybridization and immunohistochemistry. Proteins purified from experimental xenografts and malignant tumors using antibody- or lectin-affinity columns in the presence of 5 mM EDTA were assayed for seprase activation in vivo. Seprase expression and activation occur most prevalently in ovarian carcinoma, but were also detected in four other malignant tumor types, including adenocarcinoma of the colon and stomach, invasive ductal carcinoma of the breast, and malignant melanoma. Together, these data show that, in malignant tumors, seprase is proteolytically activated to confer its substrate specificity in collagen proteolysis and tumor invasion.

Chen, Donghai; Kennedy, Alanna; Wang, Jaw-Yuan; Zeng, Wei; Zhao, Qiang; Pearl, Michael; Zhang, Mengzhen; Suo, Zhenhe; Nesland, Jahn M.; Qiao, Yuhuan; Ng, Ah-Kau; Hirashima, Naoko; Yamane, Tetsu; Mori, Yoshiyuki; Mitsumata, Masako; Ghersi, Giulio; Chen, Wen-Tien

2006-01-01

55

Radiosensitizing effect of misonidazole in acute and fractionated irradiation of a human osteosarcoma xenograft. [/sup 60/Co  

SciTech Connect

The radiosensitizing effect of misonidazole (Ro-07-0582) in acute and fractionated irradiation of a human osteosarcoma grown in the athymic mutant nude mouse was studied. Tumor regrowth delay was used as a measure of response. The enhancement ratio of misonidazole was found to be 1.45 for an actue dose of 12.50 Gy and 1.25 for four fractions of 3.75 Gy, delivered over four consecutive days. It is concluded that the present osteosarcoma xenograft reoxygenated inadequately during the three day period which elapsed from the first to the fourth fraction of 3.75 Gy.

Rofstad, E.K.; Brustad, T.

1980-09-01

56

Monoclonal antibodies to human malignant mesothelioma  

Microsoft Academic Search

Murine monoclonal antibodies were used to identify tumor-cell membrane antigens on a new human mesothelioma cell line. Hybridomas were constructed by fusing SP2\\/0 mouse myeloma cells with spleen cells from Balb\\/C mice immunized by the human mesothelioma cell line MT-1. Hybridoma antibody was detected in 55\\/672 microculture wells that reacted to these MT-1 tumor cells by an indirect125I-protein A binding

Timothy M. Anderson; E. Carmack Holmes; Calvin J. Kosaka; Lorna Cheng; Romaine E. Saxton

1987-01-01

57

Molecular Modulation of Inhibitors of Apoptosis as a Novel Approach for Radiosensitization of Human Prostate Cancer.  

National Technical Information Service (NTIS)

The major goal of the project is to investigate the radiosensitizationactivity and mechanism of action of novel IAP-inhibitors in prostate cancer. In the second year of the project, we have investigated the in vivo radiosensitization activity of our lead ...

L. Xu

2007-01-01

58

Simultaneous Inhibition of EGFR and PI3K Enhances Radiosensitivity in Human Breast Cancer  

SciTech Connect

Purpose: Mutations in the epidermal growth factor receptor (EGFR)/phosphoinositide 3-kinase (PI3K)/Akt signaling transduction pathway are common in cancer. This pathway is imperative to the radiosensitivity of cancer cells. We aimed to investigate the radiosensitizing effects of the simultaneous inhibition of EGFR and PI3K in breast cancer cells. Methods and Materials: MCF-7 cell lines with low expression of EGFR and wild-type PTEN and MDA-MB-468 cell lines with high expression of EGFR and mutant PTEN were used. The radiosensitizing effects by the inhibition of EGFR with AG1478 and/or PI3K with Ly294002 were determined by colony formation assay, Western blot was used to investigate the effects on downstream signaling. Flow cytometry was used for apoptosis and cell cycle analysis. Mice-bearing xenografts of MDA-MB-468 breast cancer cells were also used to observe the radiosensitizing effect. Results: Simultaneous inhibition of EGFR and PI3K greatly enhanced radiosensitizing effect in MDA-MB-468 in terms of apoptosis and mitotic death, either inhibition of EGFR or PI3K alone could enhance radiosensitivity with a dose-modifying factor (DMF{sub SF2}) of 1.311 and 1.437, radiosensitizing effect was further enhanced by simultaneous inhibition of EGFR and PI3K with a DMF{sub SF2} at 2.698. DNA flow cytometric analysis indicated that dual inhibition combined with irradiation significantly induced G0/G1 phase arrest in MDA-MB-468 cells. The expression of phosphor-Akt and phosphor-Erk1/2 (induced by irradiation and PI3K inhibitor) were fully attenuated by simultaneous treatment with both inhibitors in combination with irradiation. In addition, dual inhibition combined with irradiation induced dramatic tumor growth delay in MDA-MB-468 xenografts. Conclusions: Our study indicated that simultaneous inhibition of EGFR and PI3K could further sensitize the cancer cells to irradiation compared to the single inhibitor with irradiation in vitro and in vivo. The approach may have important therapeutic implication in the treatment of a subset of breast cancer patients with high expression of EGFR and deficient function of PTEN.

Li Ping; Zhang Qing [Department of Radiation Oncology, 6th People's Hospital of Jiao Tong University, Shanghai 200233 (China); Torossian, Artour [Vanderbilt University, School of Medicine, Nashville, TN (United States); Li Zhaobin; Xu Wencai [Department of Radiation Oncology, 6th People's Hospital of Jiao Tong University, Shanghai 200233 (China); Lu Bo [Department of Radiation Oncology, Thomas Jefferson University and Hospitals, Inc. Philadelphia, PA (United States); Fu Shen, E-mail: fushen1117@gmail.com [Department of Radiation Oncology, 6th People's Hospital of Jiao Tong University, Shanghai 200233 (China)

2012-07-01

59

Asbestos Tissue Burden Study on Human Malignant Mesothelioma  

Microsoft Academic Search

Asbestos fibers in the lung and mesothelial tissues (mesotheliomatous tissue and hyaline plaque) taken from 151 human malignant mesothelioma cases were identified and characterized by high resolution analytical electron microscopy. Asbestos fibers were present in almost all of the lung tissue as well as in the mesothelial tissue. The most common asbestos types seen in the lung were an admixture

Yasunosuke SUZUKI; Steven R. YUEN

2001-01-01

60

Celecoxib Enhances the Radiosensitizing Effect of 7-Hydroxystaurosporine (UCN-01) in Human Lung Cancer Cell Lines  

SciTech Connect

Purpose: 7-Hydroxystaurosporine (UCN-01), a Chk1-specific inhibitor, showed promising in vitro and in vivo chemo- or radiosensitizing activity. However, there have been concerns about its limited therapeutic efficacy and risk of side effects. A method of enhancing the treatment efficacy of UCN-01 while not increasing its side effects on normal tissue may therefore be required to apply this drug in clinical settings. Celecoxib is a cyclooxygenase-2 (COX-2)-specific inhibitor that downregulates ataxia telangiectasia and rad3-related (ATR) protein, an upstream kinase of Chk1. In this study, we investigated whether the addition of celecoxib can potentiate the radiosensitizing effect of UCN-01. Methods and Materials: The cooperative radiosensitizing effects and the underlying molecular mechanisms of UCN-01 plus celecoxib were determined by clonogenic assay, tumor growth delay assay, flow cytometry, and Western blotting. Synergism of the three agents combined (UCN-01 plus celecoxib plus radiation) were evaluated using median drug effect analysis and drug-independent action model analysis. Results: The combination of UCN-01 and celecoxib could induce synergistic cytotoxicity and radiosensitizing effects in in vitro and in vivo systems. The combination of both drugs also cooperatively inhibited IR-induced G{sub 2}/M arrest, and increased the G{sub 2} to mitotic transition. Conclusions: Combined treatment with UCN-01 and celecoxib can exert synergistically enhanced radiosensitizing effects via cooperative inhibition of the ionizing radiation-activated G{sub 2} checkpoint. We propose that this combination strategy may be useful in clinical applications of UCN-01 for radiotherapy of cancer patients.

Kim, Young-Mee; Jeong, In-Hye [Department of Radiation Oncology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of); Pyo, Hongryull, E-mail: Quasar93@yahoo.co.kr [Department of Radiation Oncology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

2012-07-01

61

Radiosensitivity of hepatoma cell lines and human normal liver cell lines exposed to 12C6+ ions  

NASA Astrophysics Data System (ADS)

AIM To investigate the radiosensitivity of hepatoma cell lines and human normal liver cell lines METHODS Accelerated carbon ions by heavy ion research facility in Lanzhou HIRFL have high LET We employed it to study the radiosensitivity of hepatoma cell lines SMMC-7721 and human normal liver cell lines L02 using premature chromosome condensation technique PCC Cell survive was documented by a colony assay Chromatid breaks were measured by counting the number of chromatid breaks and isochromatid breaks immediately after prematurely chromosome condensed by Calyculin-A RESULTS The survival curve of the two cell lines presented a good linear relationship and the survival fraction of L02 is higher than that of SMMC-7721 Additionally the two types of G 2 phase chromosome breaks chromatid breaks and isochromatid breaks of L02 are lower than that of SMMC-7721 CONCLUSION Human normal liver cell line have high radioresistance than that of hepatoma cell line It imply that it is less damage to normal organs when radiotherapy to hepatoma

Jing, X.; Yang, J.; Li, W.; Guo, C.; Dang, B.; Wang, J.; Zhou, L.; Wei, W.; Gao, Q.

62

Toxicogenomics of A375 human malignant melanoma cells.  

PubMed

Toxicogenomics applications are increasingly applied to the evaluation of preclinical drug safety, and to explain toxicities associated with compounds at the mechanism level. In this review, we aim to describe the application of toxicogenomics tools for studying the genotoxic effect of active compounds on the gene-expression profile of A375 human malignant melanoma cells, through the other molecular functions of target genes, regulatory pathways and mechanisms of malignant melanomas. It also includes the current systems biology approaches, which are very useful for analyzing the biological system and understanding the entire mechanisms of malignant melanomas. We believe that this review would be very potent and useful for studying the toxicogenomics of A375 melanoma cells, and for further diagnostic and therapeutic applications. PMID:17716235

Cheng, Sun-Long; Huang-Liu, Rosa; Sheu, Jin-Nan; Chen, Shui-Tein; Sinchaikul, Supachok; Tsay, Gregory J

2007-08-01

63

HCG variants, the growth factors which drive human malignancies.  

PubMed

The term human chorionic gonadotropin (hCG) refers to a group of 5 molecules, each sharing the common amino acid sequence but each differing in meric structure and carbohydrate side chain structure. The 5 molecules are each produced by separate cells and each having separate biological functions. hCG and sulfated hCG are hormones produced by placental syncytiotrophoblast cells and pituitary gonadotrope cells. Hyperglycosylated hCG is an autocrine produced by placental cytotrophoblast cells. Hyperglycosylated hCG drives malignancy in placental cancers, and in testicular and ovarian germ cell malignancies. hCG? and hyperglycosylated hCG? are autocrines produce by most advanced malignancies. These molecules, particularly the malignancy promoters are presented in this review on hCG and cancer. hCG? and hyperglycosylated hCG? are critical to the growth and invasion, or malignancy of most advanced cancers. In many ways, while hCG may appear like a nothing, a hormone associated with pregnancy, it is not, and may be at the center of cancer research. PMID:22206043

Cole, Laurence A

2012-01-01

64

Poor Prognosis Associated With Human Papillomavirus ?7 Genotypes in Cervical Carcinoma Cannot Be Explained by Intrinsic Radiosensitivity  

SciTech Connect

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 clonogenic 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 HPV?9-positive tumors had better local progression-free survival compared with ?7 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 ?9 and ?7 cervical tumors (n=63). In the cell lines, 9 were ?7 and 4 ?9 positive and 3 negative. There was no difference in SF2 between ?9 and ?7 cell lines (n=14). Conclusion: The reduced radioresponsiveness of ?7 cervical tumors is not related to intrinsic radiosensitivity.

Hall, John S.; Iype, Rohan; Armenoult, Lucile S.C. [Translational Radiobiology Group, Institute of Cancer Sciences, Manchester Academic Health Science Centre, University of Manchester, Manchester (United Kingdom)] [Translational Radiobiology Group, Institute of Cancer Sciences, Manchester Academic Health Science Centre, University of Manchester, Manchester (United Kingdom); Taylor, Janet [Translational Radiobiology Group, Institute of Cancer Sciences, Manchester Academic Health Science Centre, University of Manchester, Manchester (United Kingdom) [Translational Radiobiology Group, Institute of Cancer Sciences, Manchester Academic Health Science Centre, University of Manchester, Manchester (United Kingdom); Applied Computational Biology and Bioinformatics Group, Paterson Institute for Cancer Research, Manchester (United Kingdom); Miller, Crispin J. [Applied Computational Biology and Bioinformatics Group, Paterson Institute for Cancer Research, Manchester (United Kingdom)] [Applied Computational Biology and Bioinformatics Group, Paterson Institute for Cancer Research, Manchester (United Kingdom); Davidson, Susan [Christie National Health Service Foundation Trust, Manchester (United Kingdom)] [Christie National Health Service Foundation Trust, Manchester (United Kingdom); Sanjose, Silvia de; Bosch, Xavier [Cancer Epidemiology Research Program, Catalan Institute of Oncology, L'Hospitalet de Llobregat (Spain)] [Cancer Epidemiology Research Program, Catalan Institute of Oncology, L'Hospitalet de Llobregat (Spain); Stern, Peter L. [Immunology Group, Paterson Institute for Cancer Research, Manchester (United Kingdom)] [Immunology Group, Paterson Institute for Cancer Research, Manchester (United Kingdom); West, Catharine M.L., E-mail: Catharine.West@manchester.ac.uk [Translational Radiobiology Group, Institute of Cancer Sciences, Manchester Academic Health Science Centre, University of Manchester, Manchester (United Kingdom)

2013-04-01

65

PKB\\/Akt mediates radiosensitization by the signaling inhibitor LY294002 in human malignant gliomas  

Microsoft Academic Search

The phosphoinositide 3-kinase (PI3-kinase) signaling pathway is frequently aberrantly activated in glioblastoma multiforme (GM) by mutation or loss of the 3' phospholipid phosphatase PTEN. PTEN abnormalities result in inappropriate signaling to downstream molecules including protein kinase B (PKB\\/Akt), and mammalian target of rapamycin (mTOR). PI3-kinase activation increases resistance to radiation-induced cell death; conversely, PI3-kinase inhibition enhances the sensitivity of tumors

Jean L. Nakamura; Amelia Karlsson; Nils D. Arvold; Alexander R. Gottschalk; Russell O. Pieper; David Stokoe; Daphne A. Haas-Kogan

2005-01-01

66

Inhibition of NF-kB, Clonogenicity, and Radiosensitivity of Human Cancer Cells  

Microsoft Academic Search

Background: Activation of the tran- scription factor NF-kB is part of the immediate early response of tissues to ionizing irradiation. This pathway has been shown to protect cells from tumor necrosis factor-a, chemotherapy, and radiation therapy-induced apoptosis (programmed cell death). However, be- cause the role of NF-kB as a modifier of the intrinsic radiosensitivity of cancer cells is less clear,

Frank Pajonk; Katja Pajonk; William H. McBride

67

Radiosensitization of paclitaxel, etanidazole and paclitaxel+etanidazole nanoparticles on hypoxic human tumor cells in vitro  

Microsoft Academic Search

Paclitaxel and etanidazole are hypoxic radiosensitizers that exhibit cytotoxic action at different mechanisms. The poly(d,l-lactide-co-glycolide) (PLGA) nanoparticles containing paclitaxel, etanidazole and paclitaxel+etanidazole were prepared by o\\/w and w\\/o\\/w emulsification-solvent evaporation method. The morphology of the nanoparticles was investigated by scanning electron microscope (SEM). The drug encapsulation efficiency (EE) and release profile in vitro were measured by high-performance liquid chromatography (HPLC).

Cheng Jin; Ling Bai; Hong Wu; Furong Tian; Guozhen Guo

2007-01-01

68

Hemoglobin enhances tissue factor expression on human malignant cells.  

PubMed

Tissue Factor (TF) is a transmembrane glycoprotein that complexes with factor VII/activated factor VII to initiate blood coagulation. TF may be expressed on the surface of various cells including monocytes and endothelial cells. Over-expression of TF in human tumor cell lines promotes metastasis. We recently showed that hemoglobin (Hb) forms a specific complex with TF purified from human malignant melanoma cells and enhances its procoagulant activity (PCA). To further study this interaction, we examined the effect of Hb on the expression of TF on human malignant (TF+) cells and KG1 myeloid leukemia (TF-) cells. Human melanoma A375 and J82 bladder carcinoma cells, which express TF at moderate and relatively high levels, respectively, were incubated with varying concentrations (0-1.5 mg/ml) of Hb. After washing, cells were analyzed for Hb binding and TF expression using flow cytometry and confocal microscopy. Hb bound to the cells in a concentration-dependent manner, and increased both TF expression and PCA. The human A375 malignant melanoma cells incubated with Hb (1 mg/ml) expressed up to six times more TF antigen than cells without Hb. This increase in TF expression and PCA of intact cells incubated with Hb was significantly inhibited by cycloheximide at a concentration of 10 microg/ml (P < 0.01). An increase in total cellular TF antigen content was demonstrated by specific immunoassay. In contrast, Hb (5 mg/ml) did not induce TF expression and PCA on KG1 cells as determined by flow cytometry and TF (FXAA) activity. We conclude that Hb specifically binds to TF-bearing malignant cells and increases their PCA. This effect seems to be at least partly due to de novo synthesis of TF and increased surface expression. However, the exact mechanism by which Hb binds and upregulates TF expression remains to be determined. PMID:11414630

Siddiqui, F A; Amirkhosravi, A; Amaya, M; Meyer, T; Biggerstaff, J; Desai, H; Francis, J L

2001-04-01

69

Eliminating malignant contamination from therapeutic human spermatogonial stem cells  

PubMed Central

Spermatogonial stem cell (SSC) transplantation has been shown to restore fertility in several species and may have application for treating some cases of male infertility (e.g., secondary to gonadotoxic therapy for cancer). To ensure safety of this fertility preservation strategy, methods are needed to isolate and enrich SSCs from human testis cell suspensions and also remove malignant contamination. We used flow cytometry to characterize cell surface antigen expression on human testicular cells and leukemic cells (MOLT-4 and TF-1a). We demonstrated via FACS that EpCAM is expressed by human spermatogonia but not MOLT-4 cells. In contrast, HLA-ABC and CD49e marked >95% of MOLT-4 cells but were not expressed on human spermatogonia. A multiparameter sort of MOLT-4–contaminated human testicular cell suspensions was performed to isolate EpCAM+/HLA-ABC–/CD49e– (putative spermatogonia) and EpCAM–/HLA-ABC+/CD49e+ (putative MOLT-4) cell fractions. The EpCAM+/HLA-ABC–/CD49e– fraction was enriched for spermatogonial colonizing activity and did not form tumors following human-to–nude mouse xenotransplantation. The EpCAM–/HLA-ABC+/CD49e+ fraction produced tumors following xenotransplantation. This approach could be generalized with slight modification to also remove contaminating TF-1a leukemia cells. Thus, FACS provides a method to isolate and enrich human spermatogonia and remove malignant contamination by exploiting differences in cell surface antigen expression.

Dovey, Serena L.; Valli, Hanna; Hermann, Brian P.; Sukhwani, Meena; Donohue, Julia; Castro, Carlos A.; Chu, Tianjiao; Sanfilippo, Joseph S.; Orwig, Kyle E.

2013-01-01

70

Ectopically hTERT expressing adult human mesenchymal stem cells are less radiosensitive than their telomerase negative counterpart  

SciTech Connect

During the past several years increasing evidence indicating that the proliferation capacity of mammalian cells is highly radiosensitive, regardless of the species and the tissue of origin of the cells, has accumulated. It has also been shown that normal bone marrow cells of mice have a similar radiosensitivity to other mammalian cells so far tested. In this study, we investigated the genetic effects of ionizing radiation (2.5-15 Gy) on normal human mesenchymal stem cells and their telomerised counterpart hMSC-telo1. We evaluated overall genomic integrity, DNA damage/repair by applying a fluorescence-detected alkaline DNA unwinding assay together with Western blot analyses for phosphorylated H2AX and Q-FISH was applied for investigation of telomeric damage. Our results indicate that hMSC and TERT-immortalized hMSCs can cope with relatively high doses of {gamma}-rays and that overall DNA repair is similar in the two cell lines. The telomeres were extensively destroyed after irradiation in both cell types suggesting that telomere caps are especially sensitive to radiation. The TERT-immortalized hMSCs showed higher stability at telomeric regions than primary hMSCs indicating that cells with long telomeres and high telomerase activity have the advantage of re-establishing the telomeric caps.

Serakinci, Nedime [Department of Human Genetics, University of Aarhus, Aarhus (Denmark) and Institute of Medical Biology, Department of Anatomy and Neurobiology, Southern Denmark University, Odense (Denmark)]. E-mail: nserakinci@health.sdu.dk; Christensen, Rikke [Department of Human Genetics, University of Aarhus, Aarhus (Denmark); Graakjaer, Jesper [Department of Clinical Genetics, Vejle County Hospital, Vejle (Denmark); Cairney, Claire J. [Centre for Oncology and Applied Pharmacology, University of Glasgow, Cancer Research UK, Beatson Laboratories, Garscube Estate, Glasgow (United Kingdom); Keith, W. Nicol [Centre for Oncology and Applied Pharmacology, University of Glasgow, Cancer Research UK, Beatson Laboratories, Garscube Estate, Glasgow (United Kingdom); Alsner, Jan [Department of Experimental Clinical Oncology, Aarhus University Hospital, Aarhus (Denmark); Saretzki, Gabriele [Henry Wellcome Laboratory for Biogerontology, Newcastle General Hospital, University of Newcastle upon Tyne, Newcastle (United Kingdom); Kolvraa, Steen [Department of Clinical Genetics, Vejle County Hospital, Vejle (Denmark)

2007-03-10

71

P2X7 receptor activation leads to increased cell death in a radiosensitive human glioma cell line.  

PubMed

Gliomas are the most lethal tumors of central nervous system. ATP is an important signaling molecule in CNS and it is a selective P2X7 purinergic receptor ligand at high concentrations. Herein, we investigated whether the activation of P2X7R might be implicated in death of a radiosensitive human glioma lineage. The effects of P2X7R agonists (ATP and BzATP) and irradiation (2 Gy) on glioma cells were analyzed by MTT assay and annexin-V/PI determination, whereas mRNA and protein P2X7R expression was assessed by qRT-PCR and flow cytometry, respectively. P2X7R pore formation was functionality examined by analyzing ethidium bromide uptake. The human glioma cells U-138 MG and U-251 MG were resistant to death when treated with either ATP (5 mM) or BzATP (100 ?M), but the radiosensitive M059J glioma cells displayed a significant decrease of cell viability (32.4 ± 4.1 % and 25.6 ± 3.3 %, respectively). The M059J lineage expresses significantly higher mRNA P2X7R levels when compared to the U-138 MG and U-251 cell lines (0.40 ± 0.00; 0.28 ± 0.01, and 0.31 ± 0.01, respectively), and irradiation upregulated P2X7R expression (0.55 ± 0.08) in this lineage. Noteworthy, P2X7R protein doubled after irradiation on M059J lineage, and increased in 50 % and 42.6 % when comparing M059J-irradiated to irradiated U-138 MG and U-251 MG cells, respectively. Ethidium bromide uptake was significantly increased in 104 % and 77.8 % when comparing M059J to U-138 MG and U-251MG, respectively. Finally, the selective P2X7R antagonist A740003 significantly decreased the cell death caused by irradiation. We provide novel evidence indicating that M059J human glioma cell line is ATP-P2X7R sensitive, pointing out the relevance of the purinergic P2X7R on glioma radiosensitivity. PMID:22644907

Gehring, Marina Petersen; Pereira, Talita Carneiro Brandão; Zanin, Rafael Fernandes; Borges, Magali Carvalho; Braga Filho, Aroldo; Battastini, Ana Maria Oliveira; Bogo, Maurício Reis; Lenz, Guido; Campos, Maria Martha; Morrone, Fernanda Bueno

2012-12-01

72

The status of microRNA-21 expression and its clinical significance in human cutaneous malignant melanoma.  

PubMed

Dysregulation of microRNA-21 plays critical roles in tumor initiation and progression. The purpose of this study was to investigate the status of microRNA-21 expression in human cutaneous malignant melanoma and determine its clinical significance. TaqMan(®) real-time RT-PCR assay was performed to examine the expression of microRNA-21 in 10 cases of dysplastic nevi, 86 cases of primary cutaneous melanomas, 10 cases of melanoma metastases. The correlation of microRNA-21 expression with clinicopathological factors or prognosis of patients with cutaneous melanoma was statistically analyzed. Additionally, the effects of microRNA-21 expression on growth, apoptosis and chemo- or radiosensitivity of melanoma cells were also investigated by transfection of microRNA-21 inhibitor. We firstly showed that increased levels of microRNA-21 expression were shown from dysplastic nevi to primary cutaneous melanomas to melanoma metastases. Moreover, high miR-21 expression was found to be correlated with Breslow thickness and advanced clinical stage. Patients with high microRNA-21 expression showed shorter 5-year disease-free or overall survival than those with low microRNA-21 expression. Furthermore, multivariate regression analysis showed that the status of microRNA-21 expression was an independent prognostic factor for overall survival of patients. Antisense-mediated microRNA-21 inhibition could significantly suppress growth, increase apoptosis and enhance chemo- or radiosensitivity of human cutaneous melanoma cells by inducing the increased Bax/Bcl-2 ratio. Thus, the status of microRNA-21 might be an independent prognostic factor for patients with cutaneous melanoma, and microRNA-21 has the potential of being a novel molecular target for the treatment of human cutaneous melanoma. PMID:22130252

Jiang, Li; Lv, Xiaoxing; Li, Jing; Li, Jinqing; Li, Xueyong; Li, Wangzhou; Li, Yuejun

2012-10-01

73

Inhibition of UBE2D3 Expression Attenuates Radiosensitivity of MCF-7 Human Breast Cancer Cells by Increasing hTERT Expression and Activity  

PubMed Central

The known functions of telomerase in tumor cells include replenishing telomeric DNA and maintaining cell immortality. We have previously shown the existence of a negative correlation between human telomerase reverse transcriptase (hTERT) and radiosensitivity in tumor cells. Here we set out to elucidate the molecular mechanisms underlying regulation by telomerase of radiosensitivity in MCF-7 cells. Toward this aim, yeast two-hybrid (Y2H) screening of a human laryngeal squamous cell carcinoma radioresistant (Hep2R) cDNA library was first performed to search for potential hTERT interacting proteins. We identified ubiquitin-conjugating enzyme E2D3 (UBE2D3) as a principle hTERT-interacting protein and validated this association biochemically. ShRNA-mediated inhibition of UBE2D3 expression attenuated MCF-7 radiosensitivity, and induced the accumulation of hTERT and cyclin D1 in these cells. Moreover, down-regulation of UBE2D3 increased hTERT activity and cell proliferation, accelerating G1 to S phase transition in MCF-7 cells. Collectively these findings suggest that UBE2D3 participates in the process of hTERT-mediated radiosensitivity in human breast cancer MCF-7 cells by regulating hTERT and cyclin D1.

Hu, Liu; Li, Fen; Ren, Li; Yu, Haijun; Liu, Yu; Xia, Ling; Lei, Han; Liao, Zhengkai; Zhou, Fuxiang; Xie, Conghua; Zhou, Yunfeng

2013-01-01

74

Radiosensitization of Human Vascular Endothelial Cells Through Hsp90 Inhibition With 17-N-Allilamino-17-Demethoxygeldanamycin  

SciTech Connect

Purpose: In addition to invasive tumor cells, endothelial cells (ECs) of the tumor vasculature are an important target for anticancer radiotherapy. The purpose of the present work is to investigate how 17-N-allilamino-17-demethoxygeldanamycin (17AAG), known as an anticancer drug inhibiting heat shock protein 90 (Hsp90), modifies radiation responses of human vascular ECs. Methods and Materials: The ECs cultured from human umbilical veins were exposed to {gamma}-irradiation, whereas some EC samples were pretreated with growth factors and/or 17AAG. Postirradiation cell death/survival and morphogenesis were assessed by means of terminal deoxynucleotidyl transferase biotin-deoxyuridine triphosphate nick end labeling or annexin V staining and clonogenic and tube-formation assays. The 17AAG-affected expression and phosphorylation of radioresistance-related proteins were probed by means of immunoblotting. Dominant negative or constitutively activated Akt was transiently expressed in ECs to manipulate Akt activity. Results: It was found that nanomolar concentrations of 17AAG sensitize ECs to relatively low doses (2-6 Gy) of {gamma}-irradiation and abolish the radioprotective effects of vascular endothelial growth factor and basic fibroblast growth factor. The drug-induced radiosensitization of ECs seems to be caused by prevention of Hsp90-dependent phosphorylation (activation) of Akt that results in blocking the radioprotective phosphatidylinositol 3-kinase/Akt pathway. Conclusions: Clinically achievable concentrations of 17AAG can decrease the radioresistance intrinsic to vascular ECs and minimize the radioprotection conferred upon them by tumor-derived growth factors. These findings characterize 17AAG as a promising radiosensitizer for the tumor vasculature.

Kabakov, Alexander E. [Department of Radiation Biochemistry, Medical Radiology Research Center, Obninsk (Russian Federation)], E-mail: aekabakov@hotmail.com; Makarova, Yulia M.; Malyutina, Yana V. [Department of Radiation Biochemistry, Medical Radiology Research Center, Obninsk (Russian Federation)

2008-07-01

75

Correlation between the radiosensitivity in vitro of clones and variants derived from a human melanoma cell line and their spontaneous metastatic potential in vivo.  

PubMed

With an experimental model of spontaneous lung metastases of human melanoma in immunosuppressed newborn rats, a large panel of clones and variants with different metastatic potential were derived from a single human melanoma parental cell line (M4Be). Seven clones and variants from M4Be were selected, respectively, for their low (parental, clone 1), intermediate (clones 2 and 3, subvariant 1-) and high (variant 1, subvariant 1+, clone 4) metastatic potential. This paper investigates the relationship between the in vivo metastatic potential of the eight cell lines and their sensitivity to ionizing radiation in vitro (range 0.05-7 Gy). The radiosensitivity was estimated from the mean inactivation dose, a parameter equal to the area under the survival curve plotted in linear coordinates. Examination of the eight survival curves, obtained with cells cultured for no more than five passages after defrost, shows that clone 1, subvariant 1- and the M4be parental line are the most radioresistant cells, clone 4 and subvariant 1+ are the most radiosensitive cells, while clones 2 and 3 and variant 1 showed an intermediate response to radiation. The metastatic potential in vivo of the parental line and the seven sublines is significantly correlated to their radiosensitivity in vitro: the higher the metastatic potential, the higher the radiosensitivity. PMID:7874696

Thomas, C P; Buronfosse, A; Portoukalian, J; Fertil, B

1995-01-27

76

Radiosensitization by dimethylbenzanthracene, diphenylcyclopropenone and aminoanthraquinones.  

PubMed

Radiosensitization of mice by dimethylbenzanthracene, diphenylcyclopropenone and aminoanthraquinones was investigated in a model where survival time after lethal radiation was scored. Survival time was shortened by nontoxic doses of the chemicals. The used in vivo system confirmed the radiosensitizing potential of dimethylbenzanthracene reported previously with in vitro studies. Moreover, radiosensitizing properties of diphenylcyclopropenone and aminoanthraquinones could be demonstrated. The sensitizing interaction of these chemicals with radiation adds a new facet to their toxicological spectrum and could, by enhancing radiation effects, influence estimates of risk. On the other hand, diphenylcyclopropenone or aminoanthraquinones deserve consideration as topical sensitizers in conditions where radiation is indicated to treat cutaneous malignancies. PMID:7473893

Floersheim, G L

1995-05-01

77

In vitro and in vivo radiosensitization of human glioma U251 cells induced by upregulated expression of SLC22A18.  

PubMed

Our previous study showed that solute carrier family 22 (organic cation transporter) member 18 (SLC22A18) downregulation via promoter methylation was associated with the development and progression of glioma, and the elevated expression of SLC22A18 was found to increase the sensitivity of glioma U251 cells to the anticancer drug 1,3-bis(2-chloroethyl)-1-nitrosourea. In this study, we investigated the possible upregulated expression of SLC22A18-induced enhancement of radiosensitivity of human glioma U251 cells in order to provide evidence in support of further clinical investigations. Stably overexpressing SLC22A18 human glioma U251 cells were generated to investigate the effect of SLC22A18 on the sensitivity of cells to irradiation in vitro using clonogenic survival assay. The apoptosis of U251 cells was examined with terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assay. DNA damage and repair were measured using ?H2AX foci. The effect of SLC22A18 on the in vivo tumor radiosensitivity was investigated in the orthotopic mice model. Upregulated expression of SLC22A18 enhanced the radiosensitivity of glioma U251 cells and also enhanced irradiation-induced apoptosis of U251 cells, but irradiation-induced apoptosis did not correlate with radiosensitizing effect of upregulated expression of SLC22A18. The repair of irradiation-induced double-strand-breaks was retarded in stably overexpressing SLC22A18 U251 cells. In the orthotopic mice model, the upregulated expression of SLC22A18 in U251 cells enhanced the effect of irradiation treatment and increased the survival time of mice. These results show that upregulated expression of SLC22A18 radiosensitizes human glioma U251 cells by suppressing DNA repair capacity. PMID:24481489

Chu, S-H; Zhou, Z-M; Karri, S; Li, Z-Q; Zhao, J-M

2014-03-01

78

Thioredoxin reductase-1 (TxnRd1) mediates curcumin-induced radiosensitization of squamous carcinoma cells  

PubMed Central

Curcumin, a plant polyphenol, is a widely studied chemopreventive agent with demonstrated antitumor activities in preclinical studies and low toxicity profiles in multiple clinical trials against human malignancies. We previously demonstrated that curcumin radiosensitizes cervical tumor cells without increasing the cytotoxic effects of radiation on normal human fibroblasts. Here we report that an inhibitory activity of curcumin on the anti-oxidant enzyme Thioredoxin Reductase-1 (TxnRd1) is required for curcumin-mediated radiosensitization of squamous carcinoma cells. Stable knockdown of TxnRd1 in both HeLa and FaDu cells nearly abolished curcumin-mediated radiosensitization. TxnRd1 knockdown cells demonstrated decreased radiation-induced reactive oxygen species and sustained ERK1/2 activation, which we previously demonstrated was required for curcumin-mediated radiosensitization. Conversely, overexpressing catalytically active TxnRd1 in HEK293 cells, with low basal levels of TxnRd1, increased their sensitivity to curcumin alone and to the combination of curcumin and ionizing radiation. These results demonstrate the critical role of TxnRd1 in curcumin-mediated radiosensitization and suggest that TxnRd1 levels in tumors could have clinical value as a predictor of response to curcumin and radiotherapy.

Javvadi, Prashanthi; Hertan, Lauren; Kosoff, Rachelle; Datta, Tatini; Kolev, Johann; Mick, Rosemarie; Tuttle, Stephen W; Koumenis, Constantinos

2010-01-01

79

Radiosensitivity of human clonogenic myeloma cells and normal bone marrow precursors: Effect of different dose rates and fractionation  

SciTech Connect

Evaluation of radiation dose rate and fractionation effects on clonogenic myeloma cells was carried out. The radiosensitivity of clonogenic myeloma cells was evaluated for seven human myeloma cell lines. The lines were maintained in liquid suspension culture. Following radiation, cells were plated in semisolid medium using methylcellulose as viscous support. Radiation doses up to 12 Gy were delivered at dose rates of 0.05 and 0.5 Gy/min by a [sup 60]Co source. Each total dose was administered either as a single dose or in multiple fractions of 2 Gy. The data were analyzed according to the linear quadratic and multi target model of irradiation. Clonogenic progenitors of the seven myeloma cell lines differed in their radiosensitivity as measured by multiple parameters. The differences were mainly observed at low dose. The most effective cytoreduction was seen when radiation was administered in a single fraction at high dose rate. The cytoreductive effect on clonogenic myeloma cells was compared for clinically practiced total body irradiation (TBI) schedules delivered either in a single or in multiple fractions without causing significant pulmonary toxicity. The administration of 12 Gy delivered in six fractions of 2 Gy resulted in a superior reduction of clonogenic cells compared to a single fraction of 5 Gy. The preparation of bone marrow transplant recipients with multiple myeloma using fractionated radiation with a total dose of 12 Gy appears to afford better ablation than a single dose of 5 Gy while maintaining a low incidence of pulmonary toxicity. 20 refs., 4 figs., 4 tabs.

Glueck, S.; Van Dyk, J.; Messner, H.A. (Univ. of Toronto, Ontario (Canada))

1994-03-01

80

Radiosensitizing effect of gold nanoparticles in carbon ion irradiation of human cervical cancer cells  

NASA Astrophysics Data System (ADS)

Noble metal nanoparticles have received considerable attention in biotechnology for their role in bio sensing due to surface plasmon resonance, medical diagnostics due to better imaging contrast and therapy. The radiosensitization effect of gold nanoparticles (AuNP) has been gaining popularity in radiation therapy of cancer cells. The better depth dose profile of energetic ion beam proves its superiority over gamma radiation for fighting against cancer. In the present work, the glucose capped gold nanoparticles (Glu-AuNP) were synthesised and internalized in the HeLa cells. Transmission electron microscopic analysis of ultrathin sections of Glu-AuNP treated HeLa cells confirmed the internalization of Glu-AuNPs. Control HeLa cells and Glu-AuNp treated HeLa cells were irradiated at different doses of 62 MeV 12C ion beam (LET - 290keV/?m) at BIO beam line of using 15UD Pelletron accelerator at Inter University Accelerator Centre, New Delhi, India. The survival fraction was assessed by colony forming assay which revealed that the dose of carbon ion for 90% cell killing in Glu-AuNP treated HeLa cells and control HeLa cells are 2.3 and 3.2 Gy respectively. This observation shows ~ 28% reduction of 12C6+ ion dose for Glu-AuNP treated HeLa cells as compared to control HeLa cells.

Kaur, Harminder; Avasthi, D. K.; Pujari, Geetanjali; Sarma, Asitikantha

2013-07-01

81

Radiosensitizing effect of gold nanoparticles in carbon ion irradiation of human cervical cancer cells  

SciTech Connect

Noble metal nanoparticles have received considerable attention in biotechnology for their role in bio sensing due to surface plasmon resonance, medical diagnostics due to better imaging contrast and therapy. The radiosensitization effect of gold nanoparticles (AuNP) has been gaining popularity in radiation therapy of cancer cells. The better depth dose profile of energetic ion beam proves its superiority over gamma radiation for fighting against cancer. In the present work, the glucose capped gold nanoparticles (Glu-AuNP) were synthesised and internalized in the HeLa cells. Transmission electron microscopic analysis of ultrathin sections of Glu-AuNP treated HeLa cells confirmed the internalization of Glu-AuNPs. Control HeLa cells and Glu-AuNp treated HeLa cells were irradiated at different doses of 62 MeV 12C ion beam (LET - 290keV/{mu}m) at BIO beam line of using 15UD Pelletron accelerator at Inter University Accelerator Centre, New Delhi, India. The survival fraction was assessed by colony forming assay which revealed that the dose of carbon ion for 90% cell killing in Glu-AuNP treated HeLa cells and control HeLa cells are 2.3 and 3.2 Gy respectively. This observation shows {approx} 28% reduction of {sup 12}C{sup 6+} ion dose for Glu-AuNP treated HeLa cells as compared to control HeLa cells.

Kaur, Harminder; Avasthi, D. K.; Pujari, Geetanjali; Sarma, Asitikantha [Inter University Accelerator Centre, Aruna Asaf Ali Marg, Post box-10502, New Delhi-110067 (India)

2013-07-18

82

Cytotoxicity of restriction enzyme-induced DNA strand breaks in radiosensitive and radioresistant human tumor cell lines  

SciTech Connect

The purpose was to examine the role of sensitivity to specific types of DNA double strand breaks in human tumor cell response. The X ray-sensitive human squamous carcinoma cell line SCC-61 and the X ray-resistant line SQ-20B were exposed to the restriction enzymes HaeIII, HinfI, PvuII, BamHI by electroporation. Cyotoxicity of these restriction endonucleases was measured by a colony formation assay. Cell killing by each enzyme occurred in a concentration-dependent manner. The radiosensitive cell line was more sensitive to all four restriction enzymes than the radioresistant line, paralleling the response to ionizing radiation. However, the magnitude of the difference was smaller than for radiation. The 5-base sticky ended cutter HinfI and 6-base blunt ended cutter PvuII were much more effective in killing cells from both lines than BamHI, a 6-base sticky ended cutter, whereas the 4-base blunt ended cutter HaeIII was intermediate in its effectiveness. Thus, enzyme sensitivity could not be related to the type of cutter or the distance between cutting sites. 14 refs., 1 fig., 2 tabs.

Kinashi, Y.; Nagasawa, H.; Little, J.B. (Harvard School of Public Health, Boston, MA (United States))

1993-09-20

83

Effect of 80.55 MeV/u 12C6+ Ions on Radiosensitivity and Cell Cycle of Human Hepatoma Cell Lines  

NASA Astrophysics Data System (ADS)

In this paper, the relationship between radiosensitivity, cell cycle alteration and the change of apoptosis in different human hepatoma cell lines irradiated by heavy ions were studied with the aim of building up the base data for clinical therapy. Exponentially growing hepatoma cell lines were irradiated by 80.55 MeV/u12C6+ ions at a dose of 0 Gy, 0.5 Gy, 1 Gy, 2 Gy, 4 Gy and 8 Gy. The radiosensitivity was assessed by means of the colony-forming assay. The DNA content, the percentage of each cell-cycle phase and the apoptosis rate were obtained with flow cytometry methods. After the irradiation, the SF2 (survival fraction at 2 gray) of SMMC-7721 cells were evidently lower than that of HepG2 cells. The S phase arrest, G2/M phase arrest delay and the apoptosis in the two hepatoma cell lines varied with the increase of the dose and repair time. The heavy ions could obviously kill the human hepatoma cell lines. Compared to HepG2 cells, SMMC-7721 cells were more radiosensitive to 12C6+ ions.

Wei, Wei; Li, Wenjian; Guo, Chuanling; Jing, Xigang; Jin, Xiaodong; Su, Xu

2008-04-01

84

The hyper-radiosensitivity effect of human hepatoma SMMC-7721 cells exposed to low dose ?-rays and 12C ions  

NASA Astrophysics Data System (ADS)

Hypersensitive response of mammalian cells in cell killing to X- and ?-rays has been reported at doses below 1 Gy. The purpose of this study was to examine the low dose sensitivity of human hepatoma SMMC-7721 cells irradiated with 60Co ?-rays and 50 MeV/u 12C ions. Experiments using ?-rays and charged particle irradiation were performed, particularly in the low dose range from 0 to 2 Gy. The survival effect of SMMC-7721 cells was measured by means of standard clonogenic assay in conjunction with a cell sorter. The result indicates SMMC-7721 cells showed hyper-radiosensitive response at low doses and increased radio-resistance at larger single doses for the carbon ions (LET = 45.2 keV/?m) and the ?-rays. However, the HRS/IRR effect caused by high-LET irradiation is different from that by low-LET radiation. This might possibly be due to the difference in the mode of energy deposition by particle beam and low-LET irradiation.

Jin, Xiao-dong; Li, Qiang; Li, Wen-jian; Wang, Ju-fang; Guo, Chuan-ling; Hao, Ji-fang

2006-04-01

85

Asbestos Fiber Analysis in the Lung and Mesothelial Tissues from 168 Cases of Human Malignant Mesothelioma  

Microsoft Academic Search

To identify and characterize asbestos fibers associated with the induction of human malignant mesothelioma, we have investigated type(s), number and size of asbestos fibers detected in the lung and mesothelial tissues taken from 168 cases of human malignant mesothelioma (including 164 males and 4 females; 156 pleural and 12 peritoneal; definite or probable; autopsy or biopsy samples). Their occupational history

Yasunosuke Suzuki; Steven R. Yuen; Richard Ashley

86

Chromosomal radiosensitivity during the G2 cell-cycle period of skin fibroblasts from individuals with familial cancer  

SciTech Connect

The authors reported previously that human cells after neoplastic transformation in culture had acquired an increased susceptibility to chromatid damage induced by x-irradiation during the G2 phase of the cell cycle. Evidence suggested that this results from deficient DNA repair during G2 phase. Cells derived from human tumors also showed enhanced G2-phase chromosomal radiosensitivity. Furthermore, skin fibroblasts from individuals with genetic diseases predisposing to a high risk of cancer, including ataxia-telangiectasia, Bloom syndrome, Fanconi anemia, and xeroderma pigmentosum exhibited enhanced G2-phase chromosomal radiosensitivity. The present study shows that apparently normal skin fibroblasts from individuals with familial cancer--i.e., from families with a history of neoplastic disease--also exhibit enhanced G2-phase chromosomal radiosensitivity. This radiosensitivity appears, therefore, to be associated with both a genetic predisposition to cancer and a malignant neoplastic state. Furthermore, enhanced G2-phase chromosomal radiosensitivity may provide the basis for an assay to detect genetic susceptibility to cancer.

Parshad, R.; Sanford, K.K.; Jones, G.M.

1985-08-01

87

Pathological changes in human malignant carcinoma treated with high-intensity focused ultrasound  

Microsoft Academic Search

The purpose of this study was to investigate the pathologic changes of extracorporeal ablation of human malignant tumors with high-intensity focused ultrasound (HIFU). HIFU treatment was performed in the 164 patients with liver cancer, breast cancer, malignant bone tumor, soft tissue sarcoma and other malignant tumors at focal peak intensities from 5000 W cm?2 to 20,000 W cm?2, with operating

Feng Wu; Wen-Zhi Chen; Jin Bai; Jian-Zhong Zou; Zhi-Long Wang; Hui Zhu; Zhi-Biao Wang

2001-01-01

88

Cellular localization of thrombomodulin in human epithelium and squamous malignancies.  

PubMed Central

Thrombomodulin is a cell surface glycoprotein that functions as an anticoagulant. Although initially identified on endothelial cells, thrombomodulin is also expressed by other vascular cells, by mesothelial cells, and by epidermal keratinocytes. To determine whether thrombomodulin is expressed by epithelial cells in locations other than skin, we conducted a survey of thrombomodulin protein and mRNA in human epithelium. Thrombomodulin protein was detected by immunohistochemistry in all samples containing stratified squamous epithelium, including oral mucosa, larynx, esophagus, uterine ectocervix, and vagina. In these tissues, thrombomodulin staining localized to the suprabasal layer, with minimal staining observed in the basal or superficial layers of epithelium. Thrombomodulin was not detected in cuboidal, simple columnar, or pseudostratified columnar epithelium and was detected variably in transitional epithelium. Thrombomodulin staining was also observed in 21 of 26 cases of invasive squamous cell carcinoma and in several examples of squamous carcinoma-in-situ and squamous metaplasia. Expression of thrombomodulin mRNA was confirmed by in situ hybridization in both normal and malignant squamous epithelium. Full-length, functionally active thrombomodulin was demonstrated in cultured squamous epithelial cells. These data demonstrate that thrombomodulin expression correlates with the squamous phenotype and suggest that hemostasis is regulated by compartmentalization of procoagulant and anti-coagulant epithelial proteins. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6

Lager, D. J.; Callaghan, E. J.; Worth, S. F.; Raife, T. J.; Lentz, S. R.

1995-01-01

89

Second malignancies in B-cell chronic lymphocytic leukaemia: possible association with human papilloma virus  

PubMed Central

Summary Second primary malignancies have long been associated with chronic lymphocytic leukaemia (CLL). We assessed secondary tumour samples from CLL and control patients for the presence of human papilloma virus (HPV). 132 CLL patients with 44 second malignancies were compared to a matched randomly-identified control population of 264 non-CLL patients with 54 solid malignancies. Polymerase chain reaction was performed with the highly conserved MY09/MY11 HPV primer. None of control samples were HPV-positive, while 53% of samples from the CLL group were positive. This report describes preliminary evidence for the presence of HPV in secondary malignancies, in patients with CLL.

Flynn, Joseph M.; Andritsos, Leslie; Lucas, David; Byrd, John C.

2014-01-01

90

High intrinsic radiosensitivity of a newly established and characterised human embryonal rhabdomyosarcoma cell line  

Microsoft Academic Search

A new human rhabdomyosarcoma cell line (HX170c) has been established from a paratesticular embryonal tumour in a 5-year-old male. The cells grew as an adherent monolayer with a doubling time of 32 h and showed pleomorphic features. Intermediate filament analysis revealed the line to be mesenchymal in origin (reactivity to vimentin and desmin antibodies). The line was tumorigenic in nude

LR Kelland; L Bingle; S Edwards; GG Steel

1989-01-01

91

Radiosensitization of human melanoma cells by ribozyme-mediated inhibition of survivin expression.  

PubMed

Survivin is a structurally unique member of the inhibitors of apoptosis protein family and is involved in the control of cell division and inhibition of apoptosis. The notion that survivin is overexpressed in most human tumors but absent in normal adult tissues with only a few exceptions has led to the proposal of survivin as a promising therapeutic target for novel anticancer therapies. In this context, we generated a hammerhead ribozyme targeting the 3' end of the CUA110 triplet in the survivin mRNA. Two human melanoma cell lines (JR8 and M14) overexpressing survivin were stably transfected with the pRc/CMV vector carrying the ribozyme sequence. Two polyclonal cell populations proven to endogenously express ribozyme and characterized by a markedly lower survivin protein level (-60% and -50%, respectively) than JR8 and M14 parental cells were selected for the study. Ribozyme-expressing cells showed a significantly (p<0.01) increased sensitivity to gamma-irradiation (as detected by clonogenic cell survival) compared to JR8 and M14 cells. Moreover, in the JR8 cell line, the extent of radiation-induced apoptosis (in terms of percentage of apoptotic nuclei in cells stained with propidium iodide and level of caspase-3 catalytic activity) was markedly greater in ribozyme-expressing cells than in parental cells. These results demonstrate for the first time that attenuation of survivin expression renders human melanoma cells more susceptible to gamma-irradiation. PMID:12648230

Pennati, Marzia; Binda, Mara; Colella, Gennaro; Folini, Marco; Citti, Lorenzo; Villa, Raffaella; Daidone, Maria Grazia; Zaffaroni, Nadia

2003-04-01

92

Impaired Pten expression in human malignant peripheral nerve sheath tumours.  

PubMed

Malignant peripheral nerve sheath tumours (MPNST) are aggressive sarcomas that develop in about 10% of patients with the genetic disease neurofibromatosis type 1 (NF1). Molecular alterations contributing to MPNST formation have only partially been resolved. Here we examined the role of Pten, a key regulator of the Pi3k/Akt/mTOR pathway, in human MPNST and benign neurofibromas. Immunohistochemistry showed that Pten expression was significantly lower in MPNST (n=16) than in neurofibromas (n=16) and normal nervous tissue. To elucidate potential mechanisms for Pten down-regulation or Akt/mTOR activation in MPNST we performed further experiments. Mutation analysis revealed absence of somatic mutations in PTEN (n=31) and PIK3CA (n=38). However, we found frequent PTEN promotor methylation in primary MPNST (11/26) and MPNST cell lines (7/8) but not in benign nerve sheath tumours. PTEN methylation was significantly associated with early metastasis. Moreover, we detected an inverse correlation of Pten-regulating miR-21 and Pten protein levels in MPNST cell lines. The examination of NF1-/- and NF1+/+Schwann cells and fibroblasts showed that Pten expression is not regulated by NF1. To determine the significance of Pten status for treatment with the mTOR inhibitor rapamycin we treated 5 MPNST cell lines with rapamycin. All cell lines were sensitive to rapamycin without a significant correlation to Pten levels. When rapamycin was combined with simvastatin a synergistic anti-proliferative effect was achieved. Taken together we show frequent loss/reduction of Pten expression in MPNST and provide evidence for the involvement of multiple Pten regulating mechanisms. PMID:23139750

Bradtmöller, Maren; Hartmann, Christian; Zietsch, Jan; Jäschke, Sebastian; Mautner, Victor-F; Kurtz, Andreas; Park, Su-Jin; Baier, Michael; Harder, Anja; Reuss, David; von Deimling, Andreas; Heppner, Frank L; Holtkamp, Nikola

2012-01-01

93

Impaired Pten Expression in Human Malignant Peripheral Nerve Sheath Tumours  

PubMed Central

Malignant peripheral nerve sheath tumours (MPNST) are aggressive sarcomas that develop in about 10% of patients with the genetic disease neurofibromatosis type 1 (NF1). Molecular alterations contributing to MPNST formation have only partially been resolved. Here we examined the role of Pten, a key regulator of the Pi3k/Akt/mTOR pathway, in human MPNST and benign neurofibromas. Immunohistochemistry showed that Pten expression was significantly lower in MPNST (n?=?16) than in neurofibromas (n?=?16) and normal nervous tissue. To elucidate potential mechanisms for Pten down-regulation or Akt/mTOR activation in MPNST we performed further experiments. Mutation analysis revealed absence of somatic mutations in PTEN (n?=?31) and PIK3CA (n?=?38). However, we found frequent PTEN promotor methylation in primary MPNST (11/26) and MPNST cell lines (7/8) but not in benign nerve sheath tumours. PTEN methylation was significantly associated with early metastasis. Moreover, we detected an inverse correlation of Pten-regulating miR-21 and Pten protein levels in MPNST cell lines. The examination of NF1?/? and NF1+/+Schwann cells and fibroblasts showed that Pten expression is not regulated by NF1. To determine the significance of Pten status for treatment with the mTOR inhibitor rapamycin we treated 5 MPNST cell lines with rapamycin. All cell lines were sensitive to rapamycin without a significant correlation to Pten levels. When rapamycin was combined with simvastatin a synergistic anti-proliferative effect was achieved. Taken together we show frequent loss/reduction of Pten expression in MPNST and provide evidence for the involvement of multiple Pten regulating mechanisms.

Zietsch, Jan; Jaschke, Sebastian; Mautner, Victor-F; Kurtz, Andreas; Park, Su-Jin; Baier, Michael; Harder, Anja; Reuss, David; von Deimling, Andreas; Heppner, Frank L.; Holtkamp, Nikola

2012-01-01

94

Metabolomics of Human Cerebrospinal Fluid Identifies Signatures of Malignant Glioma*  

PubMed Central

Cerebrospinal fluid is routinely collected for the diagnosis and monitoring of patients with neurological malignancies. However, little is known as to how its constituents may change in a patient when presented with a malignant glioma. Here, we used a targeted mass-spectrometry based metabolomics platform using selected reaction monitoring with positive/negative switching and profiled the relative levels of over 124 polar metabolites present in patient cerebrospinal fluid. We analyzed the metabolic profiles from 10 patients presenting malignant gliomas and seven control patients that did not present malignancy to test whether a small sample size could provide statistically significant signatures. We carried out multiple unbiased forms of classification using a series of unsupervised techniques and identified metabolic signatures that distinguish malignant glioma patients from the control patients. One subtype identified contained metabolites enriched in citric acid cycle components. Newly diagnosed patients segregated into a different subtype and exhibited low levels of metabolites involved in tryptophan metabolism, which may indicate the absence of an inflammatory signature. Together our results provide the first global assessment of the polar metabolic composition in cerebrospinal fluid that accompanies malignancy, and demonstrate that data obtained from high throughput mass spectrometry technology may have suitable predictive capabilities for the identification of biomarkers and classification of neurological diseases.

Locasale, Jason W.; Melman, Tamar; Song, Susan; Yang, Xuemei; Swanson, Kenneth D.; Cantley, Lewis C.; Wong, Eric T.; Asara, John M.

2012-01-01

95

Reduced GNG2 expression levels in mouse malignant melanomas and human melanoma cell lines  

PubMed Central

Heterotrimeric G protein is composed of a G?-subunit and a G??-dimer. Previous studies have revealed that G??-dimers including the G?2 subunit (Gng2/GNG2) are associated with cell proliferation, differentiation, invasion and angiogenesis. At present, however, there is no information on the expression level of Gng2/GNG2 alone in any kind of tumor. In this study, we performed DNA microarray analysis in a benign melanocytic tumor and a malignant melanoma from RET-transgenic mice (RET-mice). Gng2 transcript expression levels in a malignant melanoma were less than 1/10 of the level in a benign tumor. The difference in Gng2 transcript expression levels between benign tumors and malignant melanomas was greatest among all of the G protein ? subunits examined in this study. Moreover, protein expression levels of Gng2 were decreased in malignant melanomas compared with those in benign melanocytic tumors in RET-mice. Analysis of human malignant melanomas also showed reduced GNG2 protein expression levels in five human malignant melanoma cell lines compared with the expression levels in normal human epithelial melanocytes (NHEM). Thus, we demonstrated for the first time that Gng2/GNG2 expression levels are reduced in malignant melanoma, suggesting that GNG2 could be a novel biomarker for malignant melanoma.

Yajima, Ichiro; Kumasaka, Mayuko Y; Naito, Yuji; Yoshikawa, Toshikazu; Takahashi, Hiro; Funasaka, Yoko; Suzuki, Tamio; Kato, Masashi

2012-01-01

96

Radiosensitization induced by the anti-epidermal growth factor receptor monoclonal antibodies cetuximab and nimotuzumab in A431 cells.  

PubMed

Epidermal growth factor receptors (EGFR) are overexpressed in a wide range of malignancies including head and neck, colon, and breast cancers. It has been identified that carcinomas with high expression levels of EGFR are more resistant to radiotherapy. Therefore, inhibiting nuclear translocation of EGFR to increase the radiosensitivity of malignant cells expressing EGFR offers the potential for increasing the therapeutic index of radiotherapy. The purpose of the present study was to quantify and to compare the radiosensitizing properties of the well-known anti-EGFR antibodies, cetuximab and nimotuzumab in human epidermoid A431 overexpressing EGFR cells. Cells were treated with two concentrations of the antibodies and then irradiated with a single dose of 4 Gy. The results indicated that the two antibodies induced radiosensitization increasing the percentage of dead/dying cells and the yield of ?-H2AX foci 24 h after irradiation. Whereas cetuximab exhibited a significant increase in radiosensitization at the highest concentration, the effects of nimotuzumab were more modest. A correlation between ?-H2AX foci signals and dead/dying cells was observed. The disparity in modulation of radiation-induced DNA damage by the two antibodies could be associated with the level of their respective intrinsic cytotoxic properties. Overall, the findings highlight the potential therapeutic benefit of combination therapy with anti-EGFR antibodies and radiotherapy for relevant carcinomas. PMID:22231391

González, Jorge Ernesto; Barquinero, Joan Francesc; Lee, Manuel; García, Omar; Casaco, Angel

2012-01-15

97

Role of human papillomavirus and its detection in potentially malignant and malignant head and neck lesions: updated review  

PubMed Central

Head and neck malignancies are characterized by a multiphasic and multifactorial etiopathogenesis. Tobacco and alcohol consumption are the most common risk factors for head and neck malignancy. Other factors, including DNA viruses, especially human papilloma virus (HPV), may also play a role in the initiation or development of these lesions. The pathways of HPV transmission in the head and neck mucosal lesions include oral-genital contact, more than one sexual partner and perinatal transmission of HPV to the neonatal child. The increase in prevalence of HPV infection in these lesions may be due to wider acceptance of oral sex among teenagers and adults as this is perceived to be a form of safe sex. The prevalence of HPV in benign lesions as well as malignancies has been assessed by many techniques. Among these, the polymerase chain reaction is the most sensitive method. Review of literature reveals that HPV may be a risk factor for malignancies, but not in all cases. For confirmation of the role of HPV in head and neck squamous cell carcinoma, large population studies are necessary in an assortment of clinical settings. Prophylactic vaccination against high-risk HPV types eventually may prevent a significant number of cervical carcinomas. Of the two vaccines currently available, Gardasil® (Merck & Co., Inc.) protects against HPV types 6, 11, 16 and 18, while the other vaccine, Cervarix® (GlaxoSmithKline, Rixensart, Belgium) protects against HPV types 16 and 18 only. However, the HPV vaccine has, to the best of our knowledge, not been tried in head and neck carcinoma. The role of HPV in etiopathogenesis, prevalence in benign and malignant lesions of this area and vaccination strategies are briefly reviewed here.

Chaudhary, Ajay Kumar; Singh, Mamta; Sundaram, Shanthy; Mehrotra, Ravi

2009-01-01

98

The effect of recombinant human stem cell factor and basic fibroblast growth factor on the in vitro radiosensitivity of CD34+ hematopoietic progenitors from human umbilical cord blood.  

PubMed

Human umbilical cord blood (CB) cells selected by immunomagnetic beads for expression of the CD34 antigen were irradiated with increasing doses of x-rays (72 cGy/min). Clonogenic survival of the hematopoietic progenitors, including mixed colony-forming cells (Mix-CFC), erythroid burst-forming units (BFU-E), and granulocyte-macrophage colony-forming cells (GM-CFC), was determined in methylcellulose cultures containing placenta conditioned medium (PCM) and erythropoietin (Epo). Exponential survival curves were fitted to the data of all the colonies, resulting in D0 = 95 cGy for Mix-CFC, 136 cGy for BFU-E, and 136 cGy for GM-CFC. Additionally, the radiosensitivity of CD34+ cells was studied employing cultures containing either recombinant human stem cell factor (rhSCF) or basic fibroblast growth factor (b-FGF) in combination with PCM and Epo. It was found that the colony-forming efficiency (CFE) of non-irradiated CD34+ cells of 5.5% (range 1.4 to 14.4%) did not increase after the addition of SCF or b-FGF to the culture. The radiation response characteristics showed, however, that in the presence of SCF, the D0 value and the extrapolation number n increased significantly. This suggests the stimulation of what operationally is termed "recovery from potentially lethal damage." In contrast, no response modifying effect could be seen for b-FGF. PMID:7691633

Kreja, L; Thoma, S; Selig, C; Lamping, C; Ziegler, B L; Nothdurft, W

1993-10-01

99

Normal human colon cells suppress malignancy when fused with colon cancer cells  

SciTech Connect

Normal human colon mucosa cells and cells obtained from histologically normal tissues near that cancer were fused with human colon cancer cells. Resultant hybrid populations of normal and malignant cell fusions behaved as nonmalignant cells in culture, were unable to grow in soft agar, did not express tumor-associated antigens, and were nontumorigenic in nude mice. Autofusion of the cancer cell population led to a phenotype intermediate between normal and malignant cells. That is, the cultures had a much lower plating efficiency in soft agar, and the tumors had a longer latency and slower growth rate in nude mice. This is the first cell culture system to demonstrate that normal epithelial cells can suppress malignancy of their autologous cancer cells, and is a prelude to more extensive studies of genetic events involved in malignant conversion of human colonic epithelium.

Johnson, T.L.; Moyer, M.P. (Univ. of Texas Health Science Center, San Antonio (USA))

1990-11-01

100

GNG2 inhibits invasion of human malignant melanoma cells with decreased FAK activity.  

PubMed

It is well known that heterotrimeric G protein is composed of a G?-subunit and a G??-dimer and promotes cancer characteristics. Our recent study showed reduced G protein ?2 subunit (Gng2/GNG2) expression levels in malignant melanoma cells compared with those in benign melanocytic cells in both mice and humans. Our recent study also showed that reduced GNG2 alone augmented proliferation of malignant melanoma cells. To our knowledge, however, there is no evidence showing an effect of Gng2/GNG2 alone on metastasis of any cancers including malignant melanoma. In his study, we first prepared GNG2-overexpressed SK-Mel28 human malignant melanoma cells, in which GNG2 protein expression level was undetectably low. Migration and invasion activities of the GNG2-overexpressed malignant melanoma cells were suppressed up to 1/10th, with decreased activity of focal adhesion kinase (FAK). We then found that the expression level of GNG2 in A375M, a highly metastatic cell line, was significantly lower than that in A375P, the parental cell line of A375M. We finally showed that knockdown of GNG2 alone in A375P cells enhanced migration and invasion with increased FAK activity. Taken together, our results suggest that overexpression of GNG2 alone inhibits metastasis in human malignant melanoma cells with decreased FAK activity. Thus, GNG2 might be a candidate of molecular targets of prevention and therapy for metastasis of malignant melanoma. PMID:24660107

Yajima, Ichiro; Kumasaka, Mayuko Y; Yamanoshita, Osamu; Zou, Cunchao; Li, Xiang; Ohgami, Nobutaka; Kato, Masashi

2014-01-01

101

Lentivirus-Mediated Nox4 shRNA Invasion and Angiogenesis and Enhances Radiosensitivity in Human Glioblastoma  

PubMed Central

Radioresistance remains a significant therapeutic obstacle in glioblastoma. Reactive oxygen species (ROS) are associated with multiple cellular functions such as cell proliferation and apoptosis. Nox4 NADPH oxidase is abundantly expressed and has proven to be a major source of ROS production in glioblastoma. Here we investigated the effects of Nox4 on GBM tumor cell invasion, angiogenesis, and radiosensitivity. A lentiviral shRNA vector was utilized to stably knockdown Nox4 in U87MG and U251 glioblastoma cells. ROS production was measured by flow cytometry using the fluorescent probe DCFH-DA. Radiosensitivity was evaluated by clonogenic assay and survival curve was generated. Cell proliferation activity was assessed by a cell counting proliferation assay and invasion/migration potential by Matrigel invasion assay. Tube-like structure formation assay was used to evaluate angiogenesis ability in vitro and VEGF expression was assessed by MTT assay. Nox4 knockdown reduced ROS production significantly and suppressed glioblastoma cells proliferation and invasion and tumor associated angiogenesis and increased their radiosensitivity in vitro. Our results indicate that Nox4 may play a crucial role in tumor invasion, angiogenesis, and radioresistance in glioblastoma. Inhibition of Nox4 by lentivirus-mediated shRNA could be a strategy to overcome radioresistance and then improve its therapeutic efficacy for glioblastoma.

Han, Na; Yin, Tiejun; Huang, Lulu; Liu, Shunfang; Liu, Dongbo; Xie, Cuihong

2014-01-01

102

Incidence of malignant diseases in humans injected with radium-224.  

PubMed

The "Spiess study" follows the health of 899 persons who received multiple injections of the short-lived alpha-particle emitter (224)Ra mainly between 1945 and 1955 for the treatment of tuberculosis, ankylosing spondylitis and some other diseases. In December 2007, 124 persons were still alive. The most striking health effect, observed shortly after (224)Ra injections, was a temporal wave of 57 malignant bone tumors. During the two most recent decades of observation, a significant excess of non-skeletal malignant diseases has become evident. Expected numbers of cases were computed from the age, gender and calendar year distribution of person years at risk and incidence rates from the German Saarland Cancer Registry. Poisson statistics were applied to test for statistical significance of the standardized incidence ratios. Up to the end of December 2007, the total number of observed malignant non-skeletal diseases was 270 (248 specified cases of non-skeletal solid cancers and 22 other malignant diseases, among these 16 malignant neoplasms of lymphatic and hematopoietic tissue, six without specification of site) compared to 192 expected cases. Accounting for a 5-year minimum latent period and excluding 13 cases of non-melanoma skin cancer, 231 non-skeletal solid cancers were observed compared to 151 expected cases. Significantly increased cancer rates were observed for breast (32 compared to 9.7), soft and connective tissue (11 compared to 1.0), thyroid (7 compared to 1.0), liver (10 compared to 2.4), kidney (13 compared to 5.0), pancreas (9 compared to 4.1), bladder (16 compared to 8.0), and female genital organs (15 compared to 7.8). PMID:20726727

Nekolla, Elke Anna; Walsh, Linda; Spiess, Heinz

2010-09-01

103

Cytotoxicity of human umbilical cord blood-derived mesenchymal stem cells against human malignant glioma cells  

Microsoft Academic Search

Background  Mesenchymal stem cells (MSCs) represent a potential useful source for cell-based glioma therapies because these cells evidence\\u000a both orthodox and unorthodox plasticity and also show tropism for cancer. In this study, the authors attempted to access the\\u000a cytotoxicity of human umbilical cord blood (hUCB)-derived MSCs, with or without cytokine activations against malignant glioma\\u000a cells.\\u000a \\u000a \\u000a \\u000a Materials and methods  hUCB-derived MSCs were activated

Seok-Gu Kang; Sin Soo Jeun; Jung Yeon Lim; Seong Muk Kim; Yoon Sun Yang; Won IL Oh; Pil-Woo Huh; Chun Kun Park

2008-01-01

104

Normal Sequence and Activity but Reduced Levels of DNA-Pkcs in Human Lymphoblastic Cells Implicate Impaired Protein Stability with Radiosensitive Phenotype  

PubMed Central

Background: Non-homologous end joining (NHEJ) is the main repair pathway for DNA double strand breaks (DSBs) induced by ionizing radiation in mammalian cells. Subsets of cancer patients are hypersensitive to radiotherapy after standard doses. We sought to determine the radiosensitivity of human lymphoblastic cells (LB0005) for the abnormality in NHEJ components. Methods: Lymphoblastic (LB0005) cells are derived from an adult cancer patient with late radionecrosis. A low magnesium in vitro DNA-end joining assay was performed to examine for any defect in NHEJ activity. Single-nucleotide polymorphism (SNP) and sequence analysis were performed to examine for abnormality if any, in the genetic sequence of known NHEJ components. Results: LB0005 cells showed a gain of functional abnormality in the NHEJ pathway. While genetic sequence analysis showed no apparent mutational variations in the known classical NHEJ components, DNA-PKcs (DNA-dependent protein kinase catalytic subunit) protein is reduced in quantity compared to normal control, in spite of higher transcript levels. Conclusions: Taken together cells derived from a radiosensitive patient showed an abnormality in NHEJ activity. Proteins other than the classical NHEJ factors may regulate the NHEJ activity. Furthermore, the defect in theses regulatory proteins may have an impact on the stability of DNA-PKcs.

Yap, Seow Fong; Boo, Cynthia SK; Loong, Susan LE; Baskar, Rajamanickam

2013-01-01

105

Resveratrol enhances radiosensitivity of human non-small cell lung cancer NCI-H838 cells accompanied by inhibition of nuclear factor-kappa B activation.  

PubMed

Resveratrol, a polyphenol in red wine, possesses many pharmacological activities including cardioprotection, chemoprevention, anti-tumor effects, and nuclear factor-kappa B (NF-kappaB) inactivation. The present study was designed to evaluate the effects and possible mechanism of resveratrol in enhancing radiosensitivity of lung cancer cells. Human non-small cell lung cancer NCI-H838 cells were irradiated with or without resveratrol pretreatment. The surviving fraction and sensitizer enhancement ratio (SER) were estimated by using a colony formation assay and linear-quadratic model. The cell-cycle distribution was evaluated by using propidium iodide staining and flow cytometry. An ELISA-based assay with immobilized oligonucleotide was performed to assess the DNA binding activity of NF-kappaB. Resveratrol had no direct growth-inhibitory effect on NCI-H838 cells treated for 24 hours with doses up to 25 microM. Pretreatment with resveratrol significantly enhanced cell killing by radiation, with an SER up to 2.2. Radiation activated NF-kappaB, an effect reversed by resveratrol pretreatment. Resveratrol resulted in a decrease of cells in the G0/G1 phase and an increase in the S phase. Our results demonstrate that resveratrol enhances the radiosensitivity of NCI-H838 cells accompanied by NF-kappaB inhibition and S-phase arrest. PMID:16394628

Liao, Hui-Fen; Kuo, Cheng-Deng; Yang, Yuh-Cheng; Lin, Chin-Ping; Tai, Hung-Chi; Chen, Yu-Yawn; Chen, Yu-Jen

2005-12-01

106

'Decoy' and 'non-decoy' functions of DcR3 promote malignant potential in human malignant fibrous histiocytoma cells  

PubMed Central

Decoy receptor 3 (DcR3) is a soluble secreted protein that belongs to the tumor necrosis factor receptor (TNFR) superfamily. DcR3 inhibits the Fas ligand (FasL)/Fas apoptotic pathway by binding to FasL, competitively with Fas receptor. Previous studies have reported that overexpression of DcR3 has been detected in various human malignancies and that DcR3 functions as a ‘decoy’ for FasL to inhibit FasL-induced apoptosis. In addition, recent studies have revealed that DcR3 has ‘non-decoy’ functions to promote tumor cell migration and invasion, suggesting that DcR3 may play important roles in tumor progression by decoy and non-decoy functions. We have previously reported that overexpression of DcR3 was observed in human malignant fibrous histiocytoma (MFH), however, the roles of DcR3 in MFH have not been studied. In the present study, to elucidate the roles of DcR3 in tumor progression of MFH, we examined the effects of DcR3 inhibition on cell apoptosis, migration and invasion in human MFH cells. siRNA knockdown of DcR3 enhanced the FasL-induced apoptotic activity and significantly decreased cell migration and invasion with a decrease in the activation of phosphatidylinositol 3 kinase (PI3K)/Akt and matrix metalloproteinase (MMP)-2. The findings in this study strongly suggest that DcR3 plays important roles in tumor progression of human MFH by decoy as well as non-decoy functions and that DcR3 may serve as a potent therapeutic target for human MFH.

TODA, MITSUNORI; KAWAMOTO, TERUYA; UEHA, TAKESHI; KISHIMOTO, KENTA; HARA, HITOMI; FUKASE, NAOMASA; ONISHI, YASUO; HARADA, RISA; MINODA, MASAYA; KUROSAKA, MASAHIRO; AKISUE, TOSHIHIRO

2013-01-01

107

Downregulation of miR-210 expression inhibits proliferation, induces apoptosis and enhances radiosensitivity in hypoxic human hepatoma cells in vitro  

SciTech Connect

Hypoxia is a common feature of solid tumors and an important contributor to tumor radioresistance. miR-210 is the most consistently and robustly induced microRNA under hypoxia in different types of tumor cells and normal cells. In the present study, to explore the feasibility of miR-210 as an effective therapeutic target, lentiviral-mediated anti-sense miR-210 gene transfer technique was employed to downregulate miR-210 expression in hypoxic human hepatoma SMMC-7721, HepG2 and HuH7 cells, and phenotypic changes of which were analyzed. Hypoxia led to an increased hypoxia inducible factor-1{alpha} (HIF-1{alpha}) and miR-210 expression and cell arrest in the G{sub 0}/G{sub 1} phase in all cell lines. miR-210 downregulation significantly suppressed cell viability, induced cell arrest in the G{sub 0}/G{sub 1} phase, increased apoptotic rate and enhanced radiosensitivity in hypoxic human hepatoma cells. Moreover, apoptosis-inducing factor, mitochondrion-associated, 3 (AIFM3) was identified as a direct target gene of miR-210. AIFM3 downregulation by siRNA attenuated radiation induced apoptosis in miR-210 downregulated hypoxic human hepatoma cells. Taken together, these data suggest that miR-210 might be a potential therapeutic target and specific inhibition of miR-210 expression in combination with radiotherapy might be expected to exert strong anti-tumor effect on hypoxic human hepatoma cells. -- Highlights: Black-Right-Pointing-Pointer miR-210 downregulation radiosensitized hypoxic hepatoma. Black-Right-Pointing-Pointer AIFM3 was identified as a direct target gene of miR-210. Black-Right-Pointing-Pointer miR-210 might be a therapeutic target to hypoxic hepatoma.

Yang, Wei, E-mail: detachedy@yahoo.com.cn [Department of Radiobiology, School of Radiological Medicine and Protection, Soochow University, Suzhou (China)] [Department of Radiobiology, School of Radiological Medicine and Protection, Soochow University, Suzhou (China); Sun, Ting [Brain and Nerve Research Laboratory, The First Affiliated Hospital, Soochow University, Suzhou (China)] [Brain and Nerve Research Laboratory, The First Affiliated Hospital, Soochow University, Suzhou (China); Cao, Jianping; Liu, Fenju [Department of Radiobiology, School of Radiological Medicine and Protection, Soochow University, Suzhou (China)] [Department of Radiobiology, School of Radiological Medicine and Protection, Soochow University, Suzhou (China); Tian, Ye [Department of Radiotherapy and Oncology, The Second Affiliated Hospital, Soochow University, Suzhou (China)] [Department of Radiotherapy and Oncology, The Second Affiliated Hospital, Soochow University, Suzhou (China); Zhu, Wei [Department of Radiobiology, School of Radiological Medicine and Protection, Soochow University, Suzhou (China)] [Department of Radiobiology, School of Radiological Medicine and Protection, Soochow University, Suzhou (China)

2012-05-01

108

Recombinant human erythropoietin in the treatment of anemic patients with hematological malignancies  

Microsoft Academic Search

Patients with malignant diseases frequently develop anemia. An alternative to blood transfusions is the application of recombinant human erythropoietin. Several nonrandomized and prospective, placebo-controlled studies have demonstrated the effect and safety of erythropoietin in patients with hematological malignancies, particularly in patients with multiple myeloma and low- to intermediate-grade non-Hodgkin's lymphoma. However, in patients with myelodysplastic syndromes, the rather low response

C. Kasper

2001-01-01

109

Comparative Evaluation of Trace Metal Distribution and Correlation in Human Malignant and Benign Breast Tissues  

Microsoft Academic Search

Selected trace metals were analyzed in human malignant and nonmalignant (benign) breast tissue samples by the flame atomic\\u000a absorption spectrophotometric method. In malignant tissues, dominant mean concentrations were revealed by Na, K, Ca, Mg, Fe,\\u000a Zn, and Al at 927, 552, 231, 61.7, 36.5, 18.3, and 8.94 ?g\\/g, respectively, while the mean metal levels in benign tissues\\u000a were 903, 435, 183,

Qaisara Pasha; Salman A. Malik; Javed Iqbal; Nazia Shaheen; Munir H. Shah

2008-01-01

110

Cell cycle checkpoint status in human malignant mesothelioma cell lines: response to gamma radiation  

Microsoft Academic Search

Knowledge of the function of the cell cycle checkpoints in tumour cells may be important to develop treatment strategies for human cancers. The protein p53 is an important factor that regulates cell cycle progression and apoptosis in response to drugs. In human malignant mesothelioma, p53 is generally not mutated, but may be inactivated by SV40 early region T antigen (SV40

C Vivo; C Lecomte; F Levy; K Leroy; Y Kirova; A Renier; L Kheuang; P Piedbois; D Chopin; M C Jaurand

2003-01-01

111

Targeting eradication of malignant cells derived from human bone marrow mesenchymal stromal cells  

SciTech Connect

Human bone marrow mesenchymal stromal cells (hBMSC) have been shown to participate in malignant transformation. However, hampered by the low frequency of malignant transformation of hBMSC, we do not yet know how to prevent malignant transformation of implanted hBMSC. In this study, in order to establish a model for the eradication of hBMSC-derived malignant cells, a gene fusion consisting of a human telomerase (hTERT) promoter modified with both c-Myc and myeloid zinc finger protein2 (MZF-2) binding elements and followed by the E. coli cytosine deaminase (CD) and luciferase genes was stably transferred into hBMSC via lentiviral transduction; n-phosphonacelyl-L-aspartic acid (PALA) selection was used to generate malignant cell colonies derived from transduced hBMSC after treatment with the carcinogenic reagent BPDE. Cells that were amplified after PALA selection were used for transplantation and 5-FC pro-drug cytotoxicity tests. The results showed that PALA-resistant malignant cells could be generated from hBMSC co-induced with lentiviral transduction and treatment with Benzo(a)pyrene Diol Epoxide (BPDE); the modification of c-Myc and MZF-2 binding elements could remarkably enhance the transcriptional activities of the hTERT promoter in malignant cells, whereas transcriptional activity was depressed in normal hBMSC; malignant cells stably expressing CD under the control of the modified hTERT promoter could be eliminated by 5-FC administration. This study has provided a method for targeted eradication of malignant cells derived from hBMSC.

Yang, Yingbin [Key Laboratory of Biorheological Science and Technology, Ministry of Education, Bioengineering College, Chongqing University, Chongqing 400044 (China) [Key Laboratory of Biorheological Science and Technology, Ministry of Education, Bioengineering College, Chongqing University, Chongqing 400044 (China); School of Life Science, Southwest University, Chongqing 400715 (China); Cai, Shaoxi, E-mail: sxcai@cqu.edu.cn [Key Laboratory of Biorheological Science and Technology, Ministry of Education, Bioengineering College, Chongqing University, Chongqing 400044 (China)] [Key Laboratory of Biorheological Science and Technology, Ministry of Education, Bioengineering College, Chongqing University, Chongqing 400044 (China); Yang, Li [Key Laboratory of Biorheological Science and Technology, Ministry of Education, Bioengineering College, Chongqing University, Chongqing 400044 (China) [Key Laboratory of Biorheological Science and Technology, Ministry of Education, Bioengineering College, Chongqing University, Chongqing 400044 (China); College of Pharmacy, Jinan University, Guangzhou 510632 (China); Yu, Shuhui [Key Laboratory of Biorheological Science and Technology, Ministry of Education, Bioengineering College, Chongqing University, Chongqing 400044 (China) [Key Laboratory of Biorheological Science and Technology, Ministry of Education, Bioengineering College, Chongqing University, Chongqing 400044 (China); Library of Southwest University, Chongqing 400715 (China); Jiang, Jiahuan; Yan, Xiaoqing [Key Laboratory of Biorheological Science and Technology, Ministry of Education, Bioengineering College, Chongqing University, Chongqing 400044 (China)] [Key Laboratory of Biorheological Science and Technology, Ministry of Education, Bioengineering College, Chongqing University, Chongqing 400044 (China); Zhang, Haoxing [School of Life Science, Southwest University, Chongqing 400715 (China)] [School of Life Science, Southwest University, Chongqing 400715 (China); Liu, Lan [Department of Laboratory of Medicine, Children's Hospital of Chongqin Medical University, Chongqing 400014 (China)] [Department of Laboratory of Medicine, Children's Hospital of Chongqin Medical University, Chongqing 400014 (China); Liu, Qun [College of Life Science and Technology, Southwest University for Nationalities, Chengdu 610041 (China)] [College of Life Science and Technology, Southwest University for Nationalities, Chengdu 610041 (China); Du, Jun [Center of Microbiology, Biochemistry, and Pharmacology, School of Pharmaceutical Science, Sun Yat-Sen University, Guangzhou 510080 (China)] [Center of Microbiology, Biochemistry, and Pharmacology, School of Pharmaceutical Science, Sun Yat-Sen University, Guangzhou 510080 (China); Cai, Shaohui [College of Pharmacy, Jinan University, Guangzhou 510632 (China)] [College of Pharmacy, Jinan University, Guangzhou 510632 (China); Sung, K.L. Paul [Key Laboratory of Biorheological Science and Technology, Ministry of Education, Bioengineering College, Chongqing University, Chongqing 400044 (China) [Key Laboratory of Biorheological Science and Technology, Ministry of Education, Bioengineering College, Chongqing University, Chongqing 400044 (China); Departments of Orthopaedic Surgery and Bioengineering, University of California, SD 0412 (United States)

2010-12-10

112

The potential value of the neutral comet assay and ?H2AX foci assay in assessing the radiosensitivity of carbon beam in human tumor cell lines  

PubMed Central

Background Carbon ions (12C6+) are high linear energy transfer (LET) radiation characterized by higher relative biological effectiveness than low LET radiation. The assessment of tumour radiosensitivity would be particularly useful in optimizing the radiation dose during radiotherapy. The aim of the current study was to evaluate the potential value of the neutral comet assay and ?H2AX foci assay in assessing 12C6+ radiosensitivity of tumour cells. Materials and methods The doses of 12C6+ and X-rays used in the present study were 2 and 4 Gy. The survival fraction, DNA double-strand breaks (DSB) and repair kinetics of DSB were assayed with clonogenic survival, neutral comet assay and ?H2AX foci assay in human cervical carcinoma HeLa cells, hepatoma HepG2 cells, and mucoepidermoid carcinoma MEC-1 cells at the time points of 0.5, 4, 16 and 24 h after 12C6+ and X-rays irradiation. Results The survival fraction for 12C6+ irradiation was much more inhibited than for X-rays (p < 0.05) in all three tumour cell lines tested. Substantial amounts of residual damage, assessed by the neutral comet assay, were present after irradiation (p < 0.05). The highest residual damage was observed at 0.5 or 4 h, both for 12C6+ and X-ray irradiation. However, the residual damage in HeLa and MEC-1 cells was higher for 12C6+ than X-rays (p < 0.05). The strongest induction of ?H2AX foci was observed after 30 min, for all three tumour cell lines (p < 0.01). The franction of ?H2AX foci persisted for at least 24 h after 12C6+ irradiation; in HeLa cells and MEC-1 was higher than after X-ray irradiation (p < 0.05). The correlation coefficients between the clonogenic survival, neutral comet assay and ?H2AX foci assay were not statistically significant, except for some tumour cells at individual irradiation doses and types. Conclusions Our study demonstrated that the neutral comet assay and ?-H2AX foci assay could be used to assess the radiosensitivity of 12C6+ in human tumour cells.

Zhao, Jin; Guo, Zhong; Zhang, Hong; Wang, Zhenhua; Song, Lei; Ma, Jianxiu; Pei, Shuyan; Wang, Chenjing

2013-01-01

113

Human ovarian tissue cortex surrounding benign and malignant lesions.  

PubMed

Objective: To quantify the number of follicles in patients with ovarian pathologies, benign and malignant, in pregnant and nonpregnant states and to determine how the presence of ovarian masses and BRCA status affects follicular counts. Materials and Methods: Slides from 134 reproductive-aged women undergoing oophorectomy were examined using light microscopy by 3 independent counters blinded to the diagnosis. In all, 20 patients had cancer, 69 had benign conditions, and 35 patients were BRCA+ or had a strong family history of breast and/or ovarian cancer. In all, 10 women were either pregnant or immediately postpartum. Results: Patients undergoing risk-reducing surgery had significantly decreased follicle count compared to physiologic control. Patients with cancer had significantly decreased counts compared to all other groups. There were no differences within the benign cohort. Conclusions: When compared to benign masses, the cortex surrounding an ovarian malignancy has decreased follicle density. The stretch impact may minimize any impact on total follicle numbers. Furthermore, there may be a proliferation of ovarian stroma, with the same number of follicles spread over a larger surface area. This information is important when counseling women with ovarian masses regarding the use of ovarian tissue cryopreservation. PMID:24096576

Pavone, Mary Ellen; Hirshfeld-Cytron, Jennifer; Tingen, Candace; Thomas, Cristina; Thomas, Jessina; Lowe, M Patrick; Schink, Julian C; Woodruff, Teresa K

2014-05-01

114

Heterochromatin protein 1 expression is reduced in human thyroid malignancy.  

PubMed

Owing to the loss of heterochromatin integrity that occurs during thyroid tumorigenesis, the expression of Heterochromatin Protein 1 isoforms HP1? and HP1? was assessed by immunohistochemistry in 189 thyroid tumors and non-neoplastic tissues. Expression of HP1? was significantly decreased in all thyroid lesions, except in follicular adenomas, when compared with matched adjacent normal tissue. This loss of HP1? expression may in part be caused by microRNA dysregulation. An example is miR-205, a microRNA that is abundantly upregulated in thyroid carcinomas and shown to reduce the expression of HP1?. In contrast to HP1?, HP1? expression was only reduced in metastatic carcinomas and poorly differentiated lesions. These results suggest the reduction of HP1? followed by a decrease in HP1? contributes to the pathogenesis of thyroid carcinomas, and their loss is a potential marker of thyroid malignancy and metastatic potential, respectively. PMID:24840329

Tretiakova, Maria S; Bond, Sarah D; Wheeler, David; Contreras, Alejandro; Kocherginsky, Masha; Kroll, Todd G; Hale, Tracy K

2014-07-01

115

Physical map of a YAC contig containing the region of the human gene (HYRC) complementing hyper-radiosensitivity of the scid mouse mutation.  

PubMed

We previously mapped the putative human HYRC (the hyper-radiosensitivity of the scid mutation, complementing gene) to human chromosome 8q11.1 by fluorescence in situ hybridization (FISH) using Alu-based PCR products from a mouse-human scid radiation cell hybrid (RD15/5) as probes. From a cosmid library constructed from RD15/5, 57 cosmid clones containing human DNA inserts were isolated. 18 of which were mapped to 8q11. Based on the sequences of plasmid subclones of the 18 cosmids, five novel sequence-tagged-sites (STSs) were made. By a screening of the CEPH-YAC library with these STSs, five yeast artificial chromosome (YAC) clones were isolated. All these YAC clones were confirmed not to be chimeric by FISH, but two of them showed deleted human insert DNAs. Using the other 3 non-deleted YACs, we constructed a physical map covering the HYRC region. We confirmed that the recently isolated gene (the DNA-PKcs gene) which is a strong candidate for HYRC is located within the present contig and spans less than 200 kb. This map will be useful for the analysis of the genomic structure of the DNA-PKcs gene and for isolation of other complementing genes in the HYRC region. PMID:8914630

Watanabe, Y; Matsumoto, N; Ohta, T; Tsujita, T; Niikawa, N

1996-03-01

116

Talc induces apoptosis in human malignant mesothelioma cells in vitro.  

PubMed

Pleurodesis with talc is an accepted method for the treatment of symptomatic pleural effusions secondary to mesotheliomas. Patients with mesothelioma who have talc-induced pleurodesis have a lower morbidity than do those who do not have pleurodesis. The mechanisms whereby talc mediated these effects were considered to be secondary to a decrease or absence of a pleural effusion. The possibility that talc may directly affect malignant cells was not considered. The present study was designed to evaluate if talc directly effects cell death of malignant mesothelioma cells (MMC) or normal pleural mesothelial cells (PMC). Three confluent MMC and PMC were exposed to talc for 24, 48, and 72 h. In parallel experiments, glass beads similar in size to talc were included as control. Apoptosis was determined by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling (TUNEL) and DNA electrophoresis. Our results demonstrated that talc at a therapeutically achievable concentration (6 microg/cm(2)) induces significant apoptosis in MMC. Talc-induced maximum apoptosis in MMC (39.50 +/- 2.55%, 31.87 +/- 4.69%, and 15.10 +/- 3.93% in CRL-2081, CRL-5820, and CRL-5915, respectively) at 48 h, which was significantly (p < 0.05) greater than that in control cells. Electrophoresis of DNA isolated from talc-exposed MMC demonstrated the typical ladder pattern of internucleosomal DNA cleavage. Talc did not induce apoptosis in PMC, and glass beads did not cause significant apoptosis in either MMC or PMC. The present study has demonstrated that talc induces apoptosis in MMC without affecting normal mesothelial cells of the pleura. PMID:10673205

Nasreen, N; Mohammed, K A; Dowling, P A; Ward, M J; Galffy, G; Antony, V B

2000-02-01

117

Deleted in liver cancer protein family in human malignancies (Review)  

PubMed Central

The Deleted in Liver Cancer (DLC) protein family comprises proteins that exert their function mainly by the Rho GTPase-activating protein (GAP) domain and by regulation of the small GTPases. Since Rho GTPases are key factors in cell proliferation, polarity, cytoskeletal remodeling and migration, the aberrant function of their regulators may lead to cell transformation. One subgroup of these proteins is the DLC family. It was found that the first identified gene from this family, DLC1, is often lost in hepatocellular carcinoma and may be involved as a tumor suppressor in the liver. Subsequent studies evaluated the hypothesis that the DLC1 gene acts as a tumor suppressor, not only in liver cancer, but also in other types of cancer. Following DLC1, two other members of the DLC protein family, DLC2 and DLC3, were identified. However, limited published data are available concerning the role of these proteins in malignant transformation. This review focuses on the structure and the role of DLC1 and its relatives in physiological conditions and summarizes data published thus far regarding DLC function in the neoplastic process.

Lukasik, D.; Wilczek, E.; Wasiutynski, A.; Gornicka, B.

2011-01-01

118

Apoptotic effect and mechanisms of AHPN on human skin malignant melanoma cell A375  

Microsoft Academic Search

ObjectiveTo study apoptotic effects of synthetic retinoic acid 6-[3-(1-adamantyl)-4-hydroxyphenyl]-2-naphthalene carboxylic acid(AHPN) on human skin malignant melanoma A375 cells in comparison with the natural ligand all-trans-retinoic acid(ATRA) in vitro and the mechanisms related to the actions of AHPN.

Min Pan; Zhen-hui Peng; Sheng-xiang Xiao; Jian-wen Ren; Yan Liu; Xiao-li Li; Zheng-xiao Li

2008-01-01

119

Clonal analysis of benign and malignant human breast tumors by means of polymerase chain reaction  

Microsoft Academic Search

Clonal analysis was conduced on a variety of benign and malignant human breast tumors using the method based on restriction fragment length polymorphism (RFLP) of the X 120 chromosome-linked phosphoglycerokinase gene and on random inactivation of the gene by methylation. Breast carcinoma was shown to be monoclonal in origin, consistent with a somatic mutational theory. Precancerous lesions such as atypical

Shinzaburo Noguchi; Tomohiko Aihara; Hiroki Koyama; Kazuyoshi Motomura; Hideo Inaji; Shingi Imaoka

1995-01-01

120

Homophilic peptide inhibits growth of malignant murine and human B cells.  

PubMed

A homophilic peptide from the T15 plasmacytoma inhibits growth of murine and human B cell tumors. This finding confirms the hypothesis that B cell malignancies are driven by a self-binding epitope in the B cell receoptor (BCR) proposed as the pathogenesis of chronic lymphocytic leukemia (CLL). PMID:24328748

Kohler, Heinz; Bryan, Ann Jay

2013-12-01

121

Characterization of four cell lines derived from a human malignant fibrous histiocytoma of the maxillary sinus  

Microsoft Academic Search

We have established four cell lines from a human malignant fibrous histiocytoma. Each cell line had human aneuploid karyotype and DNA aneuploidy. Cells in all lines expressed CD13, CD68 and vimentin but lacked CD11, CD14, CD15, CD16, CD45, HLA class II and other mesenchymal and epithelial markers such as desmin, ?-smooth muscle, myoglobin, S-100 protein, and cytokeratin. None of the

A Mori; T Tagawa; T Kamei; T Murata; M Inui; S Ohse

2001-01-01

122

What is the malignant nature of human ductal carcinoma in situ?  

PubMed Central

Invasive, genetically abnormal carcinoma progenitor cells have been propagated from human and mouse breast ductal carcinoma in situ (DCIS) lesions, providing new insights into breast cancer progression. The survival of DCIS cells in the hypoxic, nutrient-deprived intraductal niche could promote genetic instability and the derepression of the invasive phenotype. Understanding potential survival mechanisms, such as autophagy, that might be functioning in DCIS lesions provides strategies for arresting invasion at the pre-malignant stage. A new, open trial of neoadjuvant therapy for patients with DCIS constitutes a model for testing investigational agents that target malignant progenitor cells in the intraductal niche.

Espina, Virginia; Liotta, Lance A.

2013-01-01

123

Characterization of transglutaminases in normal and malignant human leukocytes.  

PubMed

Using the fluorescent activity staining procedure, transglutaminases in human monocytes, granulocytes and lymphocytes have been characterized with respect to agarose gel electrophoretic mobility and thrombin dependence. A thrombin dependent transglutaminase was found in concanavalin A stimulated peripheral monocytes. The electrophoretic mobility of this zymogen and of platelet and plasma factor XIII was similar. With stimulated peripheral lymphocytes a similar pattern was observed. However, the potential transglutaminase activity in the lymphocyte factor XIII was lower than that in monocytes. Similar results were obtained when lymphocytes from chronic myeloid and chronic lymphocytic leukaemia patients were examined. Quantitatively, the transglutaminase activity in the leukaemic cells was estimated to be lower than the activity in normal cells. With respect to agarose gel electrophoretic mobility, a similar transglutaminase was found in concanavalin A stimulated human peripheral granulocytes. Although electrophoretically clearly separated from tissues transglutaminase, the granulocyte enzyme did not seem to require thrombin for activation. PMID:2857498

Berntorp, E; Seiving, B; Stenberg, P

1985-01-01

124

Regulation of Interleukin 8 Expression in Human Malignant Melanoma Cells  

Microsoft Academic Search

Here, we report the molecular regulation of interleukin (IL)-8 expres sion in human melanoma cells. The inflammatory cytokines ll.-l\\/f and tumor necrosis factor-«(TNF-a) up-regulated IL-8 expression, in a time- and concentration-dependent manner, in three metastatic melanoma vari ants, SBC-2 (nonmetastatic), A375P (low metastatic), and A375SM (high metastatic), by increased transcription of the IL-8 gene, leading to in creased levels of

Rakesh K. Singh; Michelle L. Varney

125

Nuclear magnetic resonance in cancer, XII: Application of NMR malignancy index to human lung tumours.  

PubMed Central

Sixty specimens of human lung tissue from 52 individuals were inspected at 22.5 MHz by proton magnetic resonance techniques. The purpose of the study was to evaluate the diagnostic capabilities of the nuclear magnetic resonance (NMR) technique for the diagnosis of malignancy. The combination of two NMR parameters (spin-lattice (T1) and spin-spin (T2) relaxation times) into a malignancy index yielded 3 cases of overlap between the two populations of tissue. The mean and standard deviations obtained were 1.966 +/- 0.262 for normal tissue, and 2.925 +/- 0.864 for malignant specimens. In addition, analysis of the electrolyte and water content of the tissues confirm that factors other than specimen water content influence the relaxation time.

Goldsmith, M.; Koutcher, J. A.; Damadian, R.

1977-01-01

126

Ku70\\/80 gene expression and DNA-dependent protein kinase (DNA-PK) activity do not correlate with double-strand break (dsb) repair capacity and cellular radiosensitivity in normal human fibroblasts  

Microsoft Academic Search

The expression of the Ku70 and Ku80 genes as well as the activity of the DNA-dependent protein kinase (DNA-PK) were studied in 11 normal human fibroblast lines. The proteins studied are known to be part of a double-strand break (dsb) repair complex involved in non-homologous recombination, as was demonstrated for the radiosensitive rodent mutant cell lines of the complementation groups

U Kasten; N Plottner; J Johansen; J Overgaard; E Dikomey

1999-01-01

127

Chemosensitivity and radiosensitivity profiles of four new human epithelial ovarian cancer cell lines exhibiting genetic alterations in BRCA2 , TGFß-RII , KRAS2 , TP53 and\\/or CDNK2A  

Microsoft Academic Search

To address the cellular basis for the response to ovarian cancer treatment, we characterized the chemosensitivity and radiosensitivity of four human epithelial ovarian cancer cell lines that harbor different genetic alterations. The TOV-21G, TOV-81D, OV-90, and TOV-112D cell lines were derived from ovarian tumors (TOV) or ascites (OV) from chemotherapy- and radiotherapy-naive patients and were characterized by their mutation spectrum

V. Samouëlian; C. M. Maugard; M. Jolicoeur; R. Bertrand; S. L. Arcand; P. N. Tonin; D. M. Provencher; A.-M. Mes-Masson

2004-01-01

128

HSF1 drives a transcriptional program distinct from heat shock to support highly malignant human cancers  

PubMed Central

SUMMARY Heat-Shock Factor 1 (HSF1), master regulator of the heat-shock response, facilitates malignant transformation, cancer cell survival and proliferation in model systems. The common assumption is that these effects are mediated through regulation of heat-shock protein (HSP) expression. However, the transcriptional network that HSF1 coordinates directly in malignancy and its relationship to the heat-shock response have never been defined. By comparing cells with high and low malignant potential alongside their non-transformed counterparts, we identify an HSF1-regulated transcriptional program specific to highly malignant cells and distinct from heat shock. Cancer-specific genes in this program support oncogenic processes: cell-cycle regulation, signaling, metabolism, adhesion and translation. HSP genes are integral to this program, however, many are uniquely regulated in malignancy. This HSF1 cancer program is active in breast, colon and lung tumors isolated directly from human patients and is strongly associated with metastasis and death. Thus, HSF1 rewires the transcriptome in tumorigenesis, with prognostic and therapeutic implications.

Mendillo, Marc L.; Santagata, Sandro; Koeva, Martina; Bell, George W.; Hu, Rong; Tamimi, Rulla M.; Fraenkel, Ernest; Ince, Tan A.; Whitesell, Luke; Lindquist, Susan

2012-01-01

129

Confocal reflectance imaging of excised malignant human bladder biopsies  

NASA Astrophysics Data System (ADS)

To evaluate the potential of reflectance confocal scanning laser microscopy (CM) for rapid imaging of non-processed freshly excised human bladder biopsies and cystectomy specimens. Freshly excised bladder tumors from three cystectomy specimens and random biopsies from twenty patients with a history of superficial bladder tumors were imaged with CM. Additional acetic acid washing prior to CM imaging was performed in some of the samples. Confocal images were compared to corresponding routine histologic sections. CM allows imaging of unprocessed bladder tissue at a subcellular resolution. Urothelial cell layers, collagen, vessels and muscle fibers can be rapidly visualized, in native state. In this regard, umbrella cells, basement membrane elucidated. Besides obvious limitations partly due to non-use of exogenous dyes, CM imaging offers several advantages: rapid imaging of the tissue in its native state like the basement membrane, normally seen only by using immunohistopathology. Reflectance CM opens a new avenue for imaging bladder cancer.

Daniltchenko, Dmitri I.; Kastein, Albrecht; Koenig, Frank; Sachs, Markus; Schnorr, Dietmar; Al-Shukri, Salman; Loening, Stefan A.

2004-08-01

130

Decreased PITX1 gene expression in human cutaneous malignant melanoma and its clinicopathological significance.  

PubMed

Background: The pituitary homeobox 1 (PITX1) protein is a member of the bicoid-related homeobox transcription factors and has essential roles in human development. Recently, the PITX1 gene has been considered as a tumor suppressor gene in various human cancers. Objective: This study examined the expression of PITX1 in the development and progression of human cutaneous malignant melanoma. Materials & Methods: Immunohistochemical and/or immunofluorescence analyses were performed to examine the histological expression of PITX1 in healthy skin and 40 cutaneous malignant melanoma cases, including 10 melanoma in situ cases. Results: Expression of PITX1 was shown in nuclei of melanocytes in normal skin. PITX1 expression was positive (labeling index: ?10%) in 21 (52.5%) cases and negative (labeling index: <10%) in 19 (47.5%) of 40 cases of primary cutaneous malignant melanoma. The mean tumor thickness in PITX1-negative cases (7.11?±?10.3 mm) was significantly higher than that in the positive cases (1.90?±?3.19 mm) (P<0.01). The numbers of cases showing metastasis were 1 (4.76%) of 21 cases in PITX1-positive cases and 7 (36.8%) of 19 cases in PITX1-negative cases; the frequency was significantly higher in PITX1-negative cases than the positive cases (P?=?0.012). Moreover, the reduction in PITX1 expression correlated significantly with clinical stage (P<0.001). Interestingly, PITX1 expression was inversely correlated with cell proliferation of cutaneous malignant melanoma (P<0.001). Conclusions: Down-regulation of PITX1 expression might contribute to the progression of cutaneous malignant melanoma via promoting cell proliferative activity. PMID:23816528

Osaki, Mitsuhiko; Chinen, Hikari; Yoshida, Yuichi; Ohhira, Takahito; Sunamura, Naohiro; Yamamoto, Osamu; Ito, Hisao; Oshimura, Mitsuo; Kugoh, Hiroyuki

2013-06-01

131

Regulation of interleukin 8 expression in human malignant melanoma cells.  

PubMed

Here, we report the molecular regulation of interleukin (IL)-8 expression in human melanoma cells. The inflammatory cytokines IL-1beta and tumor necrosis factor-alpha (TNF-alpha) up-regulated IL-8 expression, in a time- and concentration-dependent manner, in three metastatic melanoma variants, SBC-2 (nonmetastatic), A375P (low metastatic), and A375SM (high metastatic), by increased transcription of the IL-8 gene, leading to increased levels of IL-8 mRNA and protein production. Furthermore, we report that IFN-alpha and IFN-beta did not inhibit steady-state IL-8 production. However, IFN-alpha and IFN-beta inhibited IL-1beta or TNF-alpha-mediated up-regulation of IL-8 mRNA. In addition, IFN-beta demonstrated a more potent inhibitory effect at a lower concentration than did IFN-alpha. Both pretreatment and simultaneous treatment of melanoma cells with IFN-alpha or IFN-beta inhibited the IL-1beta and TNF-alpha up-regulation of IL-8 mRNA levels. This inhibition was at the transcriptional levels and was unaffected by a protein synthesis inhibitor, suggesting that this did not require de novo protein synthesis. Further, modulation of IL-8 levels by IL-1beta, alone or in combination with IFN-beta, affected the proliferation of melanoma cells. In summary, our data suggest that the up-regulation of IL-8 expression in melanoma cells is regulated at the transcriptional level and is rapidly and specifically inhibited by IFN-alpha or IFN-beta, independent of de novo protein synthesis, perhaps due to a transient modification of a preexisting factor(s). PMID:9537260

Singh, R K; Varney, M L

1998-04-01

132

Epigenetic reprogramming modulates malignant properties of human liver cancer.  

PubMed

Reversal of DNA hypermethylation and associated gene silencing is an emerging cancer therapy approach. Here we addressed the impact of epigenetic alterations and cellular context on functional and transcriptional reprogramming of hepatocellular carcinoma (HCC) cells. Our strategy employed a 3-day treatment of established and primary human HCC-derived cell lines grown as a monolayer at various cell densities with the DNMT1 inhibitor zebularine (ZEB) followed by a 3D culture to identify cells endowed with self-renewal potential. Differences in self-renewal, gene expression, tumorigenicity, and metastatic potential of spheres at generations G1-G5 were examined. Transient ZEB exposure produced differential cell density-dependent responses. In cells grown at low density, ZEB caused a remarkable increase in self-renewal and tumorigenicity associated with long-lasting gene expression changes characterized by a stable overexpression of cancer stem cell-related and key epithelial-mesenchymal transition genes. These effects persisted after restoration of DNMT1 expression. In contrast, at high cell density, ZEB caused a gradual decrease in self-renewal and tumorigenicty, and up-regulation of apoptosis- and differentiation-related genes. A permanent reduction of DNMT1 protein using short hairpin RNA (shRNA)-mediated DNMT1 silencing rendered HCC cells insensitive both to cell density and ZEB effects. Similarly, WRL68 and HepG2 hepatoblastoma cells expressing low DNMT1 basal levels also possessed a high self-renewal, irrespective of cell density or ZEB exposure. Spheres formed by low-density cells treated with ZEB or shDNMT1 displayed a high molecular similarity which was sustained through consecutive generations, confirming the essential role of DNMT1 depletion in the enhancement of cancer stem cell properties. Conclusion: These results identify DNA methylation as a key epigenetic regulatory mechanism determining the pool of cancer stem cells in liver cancer and possibly other solid tumors. (Hepatology 2014;59:2251-2262). PMID:24449497

Raggi, Chiara; Factor, Valentina M; Seo, Daekwan; Holczbauer, Agnes; Gillen, Matthew C; Marquardt, Jens U; Andersen, Jesper B; Durkin, Marian; Thorgeirsson, Snorri S

2014-06-01

133

An effective strategy for increasing the radiosensitivity of Human lung Cancer cells by blocking Nrf2-dependent antioxidant responses.  

PubMed

Radiotherapy and chemotherapeutic agents can effectively induce apoptosis through generation of reactive oxygen species (ROS). Cancer cells frequently express high levels of ROS-scavenging enzymes, which confer resistance to ROS-mediated cell death. Keap1 (Kelch-like ECH-associated protein 1) sequesters and promotes the degradation of the antioxidant response element-binding transcription factor Nrf2 (nuclear factor erythroid-2-related factor 2). In non-small-cell lung cancer (NSCLC) cell lines and NSCLC patients, Keap1 is often present as a biallelic mutant that results in constitutive activation of Nrf2 function, which contributes to cytoprotection against oxidative stress and xenobiotics. To identify small molecules that inhibit antioxidant responses and increase apoptotic death after radiotherapy, we screened a chemical library containing 8000 synthetic compounds using a cell-based luciferase assay system. 4-(2-Cyclohexylethoxy)aniline (IM3829) inhibited the increase in Nrf2-binding activity and expression of the Nrf2 target genes induced by treatment with tertiary butylhydroquinone or radiation. Combined treatment with IM3829 and radiation significantly inhibited clonogenic survival of H1299, A549, and H460 lung cancer cells. IM3829 significantly increased ROS accumulation in irradiated cells compared with cells exposed to radiation alone and led to apoptotic cell death, as confirmed by caspase-3 and PARP cleavage. In mice bearing H1299 or A549 lung cancer xenografts, IM3829 together with radiation inhibited tumor growth more effectively than radiation alone. Our findings suggest that IM3829 could be a promising radiosensitizer in lung cancer patients, particularly those with high expression of Nrf2. PMID:22684019

Lee, Saelooom; Lim, Min-Jin; Kim, Mi-Hyoung; Yu, Chi-Ho; Yun, Yeon-Sook; Ahn, Jiyeon; Song, Jie-Young

2012-08-15

134

Characterization of a highly invasive and spontaneously metastatic human malignant melanoma cell line.  

PubMed

Although the incidence of, and deaths due to, malignant melanoma are rising at a rapid rate, few experimental models mimic the highly metastatic properties associated with the pathogenesis of the human disease, making study of the disease difficult. Thus, new human models are required to understand melanoma biology, especially its metastatic properties. Here we describe C8161, a highly invasive and spontaneously metastatic human melanoma cell line, which grows progressively in the subcutis of athymic nude mice with an average doubling time of approximately 6 days. By the time the tumor reaches a diameter of 1 cm, amelanotic metastases in lymph nodes, skin, peritoneal wall, spleen and lungs have formed. By comparing C8161 to variants from other well-characterized human malignant melanomas (A375 and MeWo) with differing metastatic traits, properties presumed to be involved in metastatic propensity were examined. C8161 showed a 2- to 14-fold higher ability to invade reconstituted basement membrane barriers in the MICS and correspondingly high type-IV collagenase mRNA levels and collagenolytic activity, as compared with other melanoma cell lines. Likewise, differential adhesion to immobilized RBM or HUVEC monolayers was observed, but did not correlate to rank orders of malignant properties. Recently, a correlation between surface expression of ICAM-1 and secondary tumor formation by human melanomas has been described in several laboratories. Basal levels of ICAM-1 on C8161, A375 and MeWo human melanomas were compared, but no correlation with metastatic potential was noted. Proto-oncogene expression in C8161 cells was compared with A375P and A375M variants using Northern blot analysis. c-myc expression was 6-fold greater than both A375 variants; c-fos expression was 3.4-fold less than A375P and 1.7-fold less than A375M; c-jun in C8161 cells was 2.5-fold and 2.1-fold greater than expression in A375P and A375M, respectively. Because C8161 is so highly malignant, amenable to experimental manipulation, and its behavior in nude mice mimics the clinical course of malignant melanoma, this cell line will prove valuable for studying properties associated with human melanoma tumor progression. PMID:1671030

Welch, D R; Bisi, J E; Miller, B E; Conaway, D; Seftor, E A; Yohem, K H; Gilmore, L B; Seftor, R E; Nakajima, M; Hendrix, M J

1991-01-21

135

Human non-malignant and malignant brain tumor derived cell cultures: proliferation and sensitivity to natural human fibroblast (beta) interferon.  

PubMed

Twenty-one human brain tumor biopsies were processed by mechanical and enzymatic methods to produce mixed cell suspensions. Cultures were prepared in small plastic flasks, and primary outgrowth occurred in 16/21 cultures. The period required for primary outgrowth ranged from 3 days to 14 days. We established serial propagation with 15/16 of the primary cultures. Sensitivity to HuIFN-beta was determined between passages 3 to 12, using a microassay based on cell viability (uptake of a supravital stain, neutral red). Extracted dye was quantified in acidic-methanol using the MR580 Microelisa Autoreader (Dynatech). We observed a broad range of responsiveness to the drug among the 12 cell-strains tested. Thus, 4 cell strains were relatively sensitive; 4 were resistant to 10(4) IRU/ml of purified HuIFN-beta. Four cell strains exhibited a level of responsiveness that was intermediate to that of these two groups. During propagation of these biopsies, cytopathology suggestive of paramyxovirus-infection appeared in 4 of the cell-strains. This characteristic was not uniformly associated with high sensitivity to human beta interferon which is a very potent, naturally occurring antiviral substance. Our results support the concept that information concerning sensitivity to HuIFN-beta and other cytostatic agents may be rapidly obtained using microcultures of brain tumor cultures in conjunction with supravital stain uptake studies. Additionally, these results suggest that further clinical studies with beta interferon should be undertaken to define the parameters which determine successful in vivo application. PMID:3572469

Cook, A W; Nidzgorski, F; Roane, P R; Mann, G; Came, P; Carter, W A

1987-01-01

136

Endoglin (CD105): A Strong Candidate for Immunologic Targeting of Tumor Neovasculature in Human Malignancies  

Microsoft Academic Search

Tumor-associated angiogenesis is a well-acknowledged therapeutic target for human malignancies, and different markers of tumor\\u000a neovasculature are actively investigated as potential candidates for antiangiogenetic therapy in cancer. Among these is endoglin\\u000a (CD105), a homodimeric transmembrane glycoprotein overexpressed on proliferating endothelial cells, which has been identified\\u000a as a functional component of the transforming growth factor-? (TGF-?) receptor system about a decade

Ester Fonsatti; Michele Maio

137

Migration of Human Dendritic Cells after Injection in Patients with Metastatic Malignancies1  

Microsoft Academic Search

Present clinical studies of active immunotherapy for malignancies using dendritic cells (DCs) require elucidation of the sites where DCs localize after injection. We evaluated the pattern of distribution of in vitro-generated, antigen-loaded, human DCs labeled with indium-111 oxyquinoline after i.v., s.c., and intradermal injection. Whereas the DCs injected i.v. localized in the lungs and then redistributed to the liver, spleen,

Michael A. Morse; R. Edward Coleman; Gamal Akabani; Nelson Niehaus; Doris Coleman; H. Kim Lyerly

1999-01-01

138

Phase I study of recombinant human tumor necrosis factor ? in advanced malignant disease  

Microsoft Academic Search

A phase I study with recombinant human tumor necrosis factor a (rhuTNF-a; Knoll AG, Ludwigshafen, FRG) in patients with advanced malignant disease was undertaken to evaluate drug toxicity (organ specifity, time course, predictability, reversibility, maximal tolerated dose), effectiveness, antigenicity and pharmacokinetics. TNF was administered as a test dose followed by daily i.v. infusions for 5 days, every 3 weeks (single

T. Moritz; N. Niederle; J. Baumann; D. May; E. Kurschel; R. Osieka; J. Kempeni; E. Schlick; C. G. Schmidt

1989-01-01

139

Fas-Mediated Apoptosis of Melanoma Cells and Infiltrating Lymphocytes in Human Malignant Melanomas  

Microsoft Academic Search

In a rodent system, melanoma cells expressing Fas ligand (FasL) could kill Fas-positive lymphocytes, suggesting that FasL expression was an essential factor for melanoma cell survival in vivo. These findings led us to investigate apoptosis, and to histochemically analyze involvement of Fas and FasL in the induction of apoptosis, in human malignant melanoma tissues. The percentages of terminal deoxynucleotidyl transferase-mediated

Tetsuo Shukuwa; Ichiro Katayama; Takehiko Koji

2002-01-01

140

Cytotoxicity of taxol in vitro against human and rat malignant brain tumors  

Microsoft Academic Search

Taxol is a novel antitumor alkaloid that has shown clinical activity against several tumors, including ovarian and breast carcinoma and melanoma. To evaluate taxol's potential as a therapy for malignant brain tumors, we measured the sensitivity of four human (U87, U373, H80, and D324) and two rat (9L, F98) brain-tumor cell lines to taxol. The cells were exposed to taxol

Mitchell A. Cahan; Kevin A. Walter; O. Michael Colvin; Henry Bremi

1994-01-01

141

Cytotoxicity of taxol in vitro against human and rat malignant brain tumors  

Microsoft Academic Search

Taxol is a novel antitumor alkaloid that has shown clinical activity against several tumors, including ovarian and breast carcinoma and melanoma. To evaluate taxol’s potential as a therapy for malignant brain tumors, we measured the sensitivity of four human (U87, U373, H80, and D324) and two rat (9L, F98) brain-tumor cell lines to taxol. The cells were exposed to taxol

Mitchell A. Cahan; Kevin A. Walter; O. Michael Colvin; Henry Brem

1994-01-01

142

p53 Mutations in Human Lymphoid Malignancies: Association with Burkitt Lymphoma and Chronic Lymphocytic Leukemia  

Microsoft Academic Search

We have investigated the frequency of p53 mutations in B- and T-cell human lymphoid malignancies, including acute lymphoblastic leukemia, the major subtypes of non-Hodgkin lymphoma, and chronic lymphocytic leukemia. p53 exons 5-9 were studied by using genomic DNA from 197 primary tumors and 27 cell lines by single-strand conformation polymorphism analysis and by direct sequencing of PCR-amplified fragments. Mutations were

Gianluca Gaidano; Paola Ballerini; Jerry Z. Gong; Giorgio Inghirami; Antonino Neri; Elizabeth W. Newcomb; Ian T. Magrath; Daniel M. Knowles; Riccardo dalla-Favera

1991-01-01

143

Autotaxin and LPA Receptors Represent Potential Molecular Targets for the Radiosensitization of Murine Glioma through Effects on Tumor Vasculature  

PubMed Central

Despite wide margins and high dose irradiation, unresectable malignant glioma (MG) is less responsive to radiation and is uniformly fatal. We previously found that cytosolic phospholipase A2 (cPLA2) is a molecular target for radiosensitizing cancer through the vascular endothelium. Autotaxin (ATX) and lysophosphatidic acid (LPA) receptors are downstream from cPLA2 and highly expressed in MG. Using the ATX and LPA receptor inhibitor, ?-bromomethylene phosphonate LPA (BrP-LPA), we studied ATX and LPA receptors as potential molecular targets for the radiosensitization of tumor vasculature in MG. Treatment of Human Umbilical Endothelial cells (HUVEC) and mouse brain microvascular cells bEND.3 with 5 µmol/L BrP-LPA and 3 Gy irradiation showed decreased clonogenic survival, tubule formation, and migration. Exogenous addition of LPA showed radioprotection that was abrogated in the presence of BrP-LPA. In co-culture experiments using bEND.3 and mouse GL-261 glioma cells, treatment with BrP-LPA reduced Akt phosphorylation in both irradiated cell lines and decreased survival and migration of irradiated GL-261 cells. Using siRNA to knock down LPA receptors LPA1, LPA2 or LPA3 in HUVEC, we demonstrated that knockdown of LPA2 but neither LPA1 nor LPA3 led to increased viability and proliferation. However, knockdown of LPA1 and LPA3 but not LPA2 resulted in complete abrogation of tubule formation implying that LPA1 and LPA3 on endothelial cells are likely targets of BrP-LPA radiosensitizing effect. Using heterotopic tumor models of GL-261, mice treated with BrP-LPA and irradiation showed a tumor growth delay of 6.8 days compared to mice treated with irradiation alone indicating that inhibition of ATX and LPA receptors may significantly improve malignant glioma response to radiation therapy. These findings identify ATX and LPA receptors as molecular targets for the development of radiosensitizers for MG.

Linkous, Amanda G.; Hu, Rong; Leahy, Kathleen M.; Yazlovitskaya, Eugenia M.; Hallahan, Dennis E.

2011-01-01

144

Enhancement of drug sensitivity of human malignancies by epidermal growth factor.  

PubMed Central

We have previously shown that epidermal growth factor (EGF) enhances the in vitro and in vivo sensitivity of human ovarian carcinoma 2008 cells to cisplatin. EGF was found to enhance selectively the in vivo toxicity of cisplatin to 2008 cell xenografts without altering the toxicity of cisplatin to non-malignant target tissues such as the kidney or bone marrow. We now show that recombinant human EGF (rhEGF) enhances the cisplatin sensitivity of cell lines representative of many other types of malignancies in addition to ovarian carcinoma, including cancers of the head and neck, cervix, colon, pancreas and prostate, as well as non-small-cell carcinoma of the lung. In addition, rhEGF was found to sensitise cells to other platinum-containing drugs and several other classes of chemotherapeutic agents. rhEGF sensitised 2008 cells not only to cisplatin, but also to carboplatin and tetraplatin, as well as taxol, melphalan and 5-fluorouracil. We conclude that modulation of drug sensitivity by rhEGF is observed in cell lines representative of many human malignancies and for multiple classes of chemotherapeutic agents, indicating that it alters one or more components of the cellular damage response that are both common between cell lines and classes of drugs and fundamental to survival. Images Figure 2

Kroning, R.; Jones, J. A.; Hom, D. K.; Chuang, C. C.; Sanga, R.; Los, G.; Howell, S. B.; Christen, R. D.

1995-01-01

145

Influence of imatinib mesylate on radiosensitivity of astrocytoma cells.  

PubMed

Imatinib mesylate (STI571), an inhibitor of alpha- and beta-platelet-derived growth factor receptors (PDGFR) and other tyrosine kinases, is a well established treatment for chronic myeloid leukaemia and gastrointestinal stromal tumours. Moreover, it is under investigation for the therapy of several other malignant tumours since protein kinases are frequently mutated or otherwise deregulated in human malignancies and they serve as a target for differentiating between tumour cells and normal tissues. The objective of this study was to determine whether gamma radiation could sensitize astrocytoma cell lines to the effects of imatinib in vitro. For this purpose, T98G and MOG-G-UVW astrocytoma cells were treated with imatinib alone or in combination with gamma radiation. The clonogenic survival assays performed with the combination of imatinib with radiation demonstrated that the drug had an additive antiproliferative effect in both cell lines considered. Imatinib confered greater radiosensitivity on the T98G tumour cells effecting a significant decrease in colony formation compared with radiation alone. These data provide a rationale to further investigate the combination of imatinib with radiation, keeping in mind that this may result in unexpected toxicities that are not observed with either treatment alone. PMID:20032406

Ranza, E; Bertolotti, A; Facoetti, A; Mariotti, L; Pasi, F; Ottolenghi, A; Nano, R

2009-11-01

146

The softening of human bladder cancer cells happens at an early stage of the malignancy process.  

PubMed

Various studies have demonstrated that alterations in the deformability of cancerous cells are strongly linked to the actin cytoskeleton. By using atomic force microscopy (AFM), it is possible to determine such changes in a quantitative way in order to distinguish cancerous from non-malignant cells. In the work presented here, the elastic properties of human bladder cells were determined by means of AFM. The measurements show that non-malignant bladder HCV29 cells are stiffer (higher Young's modulus) than cancerous cells (HTB-9, HT1376, and T24 cell lines). However, independently of the histological grade of the studied bladder cancer cells, all cancerous cells possess a similar level of the deformability of about a few kilopascals, significantly lower than non-malignant cells. This underlines the diagnostic character of stiffness that can be used as a biomarker of bladder cancer. Similar stiffness levels, observed for cancerous cells, cannot be fully explained by the organization of the actin cytoskeleton since it is different in all malignant cells. Our results underline that it is neither the spatial organization of the actin filaments nor the presence of stress fibers, but the overall density and their 3D-organization in a probing volume play the dominant role in controlling the elastic response of the cancerous cell to an external force. PMID:24778971

Ramos, Jorge R; Pabijan, Joanna; Garcia, Ricardo; Lekka, Malgorzata

2014-01-01

147

The beta subunit of human chorionic gonadotropin lacks specificity for malignant cells in serous effusions.  

PubMed

The cytologic diagnosis of malignancy is frequently straightforward. For difficult cases, multiple immunostains and immunostain panels have been investigated without consensus. beta-human chorionic gonadotropin (hCG) has been reportedly expressed in malignancies, but not in normal tissue. HCG also has been reported as a specific marker of metastases in serous fluids when detected with laboratory assays. We investigated the clinical utility of hCG in this cytologic setting. A total of 97 cases of benign and malignant effusions were studied. Each case was immunostained with monoclonal hCG using the avidin-biotin technique and diaminobenzidine as a chromogen. Additionally, a mucicarmine stain was performed on most cases. Cases were evaluated for hCG expression and mucin in a blinded fashion. After the cases were reviewed, the diagnoses were unblinded and staining patterns were evaluated. Of the 47 benign cases studied, 23 (49%) exhibited immunoreactivity to hCG in at least 5% of mesothelial cells present. In contrast, 28 of 44 (64%) adenocarcionomas exhibited a similar degree of immunostaining. In all, 21 (48%) of the adenocarcinomas were also positive for mucin; five of these mucin-positive cases were negative for hCG. The combination of mucin and hCG detected 33 of 44 (75%) adenocarcinomas. We conclude that hCG lacks the specificity for malignant cells to be of clinical use in effusion cytology. PMID:15001996

Zimmerman, Robert L; Fogt, Franz

2004-06-01

148

The softening of human bladder cancer cells happens at an early stage of the malignancy process  

PubMed Central

Summary Various studies have demonstrated that alterations in the deformability of cancerous cells are strongly linked to the actin cytoskeleton. By using atomic force microscopy (AFM), it is possible to determine such changes in a quantitative way in order to distinguish cancerous from non-malignant cells. In the work presented here, the elastic properties of human bladder cells were determined by means of AFM. The measurements show that non-malignant bladder HCV29 cells are stiffer (higher Young’s modulus) than cancerous cells (HTB-9, HT1376, and T24 cell lines). However, independently of the histological grade of the studied bladder cancer cells, all cancerous cells possess a similar level of the deformability of about a few kilopascals, significantly lower than non-malignant cells. This underlines the diagnostic character of stiffness that can be used as a biomarker of bladder cancer. Similar stiffness levels, observed for cancerous cells, cannot be fully explained by the organization of the actin cytoskeleton since it is different in all malignant cells. Our results underline that it is neither the spatial organization of the actin filaments nor the presence of stress fibers, but the overall density and their 3D-organization in a probing volume play the dominant role in controlling the elastic response of the cancerous cell to an external force.

Ramos, Jorge R; Pabijan, Joanna

2014-01-01

149

Taxanes as radiosensitizers.  

PubMed

In parallel with the discovery of the taxanes, our understanding of the molecular underpinnings that comprise the classic biologic principles of fractionated radiotherapy has rapidly evolved over the past half century. Early studies have implicated DNA as the primary target for radiation-induced lethality. More recently, however, the molecular biology involved in radiosensitization of tumor cells has been unveiled. Specifically, factors associated with DNA damage and cell killing, collectively known as the 'four Rs' of radiobiology, including (r)eassortment of tumor cells into the radiosensitive phases of the cell cycle (G2/M), (r)eoxygenation of hypoxic areas within a tumor, (r)epair of sublethal DNA damage, and (r)epopulation of surviving tumor cells, have been elucidated, and upon manipulation of each factor or a combination of factors a significant impact on radiation-associated tumor control probabilities was found. Not only does spatial cooperation have a theoretical benefit in patients with undetectable micrometastatic disease at presentation, but the manipulation of either of the 'four Rs' using taxanes provokes further local radiation-associated tumor cell killing with an associated improvement in clinical responses. Numerous studies have shown that taxanes radiosensitize tumor cells directly and/or indirectly by perturbing the tumor microenvironment in a time-dependent and dose-dependent manner. Herein, the impact of taxanes on radiobiological tenets as a mode of radiosensitizing tumor cells and their clinical implications are reviewed. PMID:24335716

Golden, Encouse B; Formenti, Silvia C; Schiff, Peter B

2014-05-01

150

Persistent Exposure to Mycoplasma Induces Malignant Transformation of Human Prostate Cells  

PubMed Central

Recent epidemiologic, genetic, and molecular studies suggest infection and inflammation initiate certain cancers, including those of the prostate. The American Cancer Society, estimates that approximately 20% of all worldwide cancers are caused by infection. Mycoplasma, a genus of bacteria that lack a cell wall, are among the few prokaryotes that can grow in close relationship with mammalian cells, often without any apparent pathology, for extended periods of time. In this study, the capacity of Mycoplasma genitalium, a prevalent sexually transmitted infection, and Mycoplasma hyorhinis, a mycoplasma found at unusually high frequency among patients with AIDS, to induce a malignant phenotype in benign human prostate cells (BPH-1) was evaluated using a series of in vitro and in vivo assays. After 19 weeks of culture, infected BPH-1 cells achieved anchorage-independent growth and increased migration and invasion. Malignant transformation of infected BPH-1 cells was confirmed by the formation of xenograft tumors in athymic mice. Associated with these changes was an increase in karyotypic entropy, evident by the accumulation of chromosomal aberrations and polysomy. This is the first report describing the capacity of M. genitalium or M. hyorhinis infection to lead to the malignant transformation of benign human epithelial cells and may serve as a model to further study the relationship between prostatitis and prostatic carcinogenesis.

Porvasnik, Stacy; Allan, Robert W.; Iczkowski, Kenneth A.; Urbanek, Cydney; Reyes, Leticia; Sakamoto, Noboru; Rosser, Charles J.

2009-01-01

151

Agarose overlay selectively improves macrocolony formation and radiosensitivity assessment in primary fibroblasts.  

PubMed

Abstract Purpose: Primary fibroblasts are not suitable for in vitro macrocolony assay due to their inability to form distinct colonies. Here we present a modification of agarose overlay that yielded extensive improvement in their colony formation and assessment of radiosensitivity. Materials and methods: Macrocolony formation was assessed in primary human fibroblasts VH10 and HDFn with or without overlay using 0.5% agarose in growth medium at 24 h post-seeding. Malignant human cell lines (A549, U87) and transformed non-malignant fibroblasts (AA8 hamster, MRC5 human) were used for comparison. Results: Agarose overlay caused significant improvement marked by early appearance (one week) of distinct colonies with high cell density and multifold higher plating efficiency than conventional macrocolony assay in VH10 and HDFn human fibroblasts. Compared to conventional assay or feeder cell supplementation, agarose overlay resulted in broader cell morphology due to improved adherence, and yielded more compact colonies. Gamma-radiation dose-response survival curves could be successfully generated for both fibroblast cell lines using this method, which yielded no such effects in the transformed/malignant cell lines tested. Conclusion: This easy and inexpensive 'agarose overlay technique' significantly and selectively improves the fibroblast plating efficiency, thus considerably reducing time and effort to greatly benefit the survival studies on primary fibroblasts. PMID:24527670

Chandna, Sudhir; Dagur, Raghubendra Singh; Mathur, Ankit; Natarajan, Adayapalam Tyagarajan; Harms-Ringdahl, Mats; Haghdoost, Siamak

2014-05-01

152

Insulin-Like Growth Factor-Type 1 Receptor Inhibitor NVP-AEW541 Enhances Radiosensitivity of PTEN Wild-Type but Not PTEN-Deficient Human Prostate Cancer Cells  

SciTech Connect

Purpose: During the past decade, many clinical trials with both monoclonal antibodies and small molecules that target the insulin-like growth factor-type 1 receptor (IGF-1R) have been launched. Despite the important role of IGF-1R signaling in radioresistance, studies of such agents in combination with radiotherapy are lagging behind. Therefore, the aim of this study was to investigate the effect of the small molecule IGF-1R kinase inhibitor NVP-AEW541 on the intrinsic radioresistance of prostate cancer cells. Methods and Materials: The effect of NVP-AEW541 on cell proliferation, cell viability, IGF-1R signaling, radiosensitivity, cell cycle distribution, and double strand break repair was determined in three human prostate cancer cell lines (PC3, DU145, 22Rv1). Moreover, the importance of the PTEN pathway status was explored by means of transfection experiments with constitutively active Akt or inactive kinase-dead Akt. Results: NVP-AEW541 inhibited cell proliferation and decreased cell viability in a time-and dose-dependent manner in all three cell lines. Radiosensitization was observed in the PTEN wild-type cell lines DU145 and 22Rv1 but not in the PTEN-deficient PC3 cell line. NVP-AEW541-induced radiosensitization coincided with downregulation of phospho-Akt levels and high levels of residual double strand breaks. The importance of PTEN status in the radiosensitization effect was confirmed by transfection experiments with constitutively active Akt or inactive kinase-dead Akt. Conclusions: NVP-AEW541 enhances the effect of ionizing radiation in PTEN wild-type, but not in PTEN-deficient, prostate cancer cells. Proper patient selection based on the PTEN status of the tumor will be critical to the achievement of optimal results in clinical trials in which the combination of radiotherapy and this IGF-1R inhibitor is being explored.

Isebaert, Sofie F., E-mail: sofie.isebaert@med.kuleuven.be [Department of Radiation Oncology, University Hospitals Leuven Campus Gasthuisberg, Leuven (Belgium); Swinnen, Johannes V. [Department of Experimental Medicine, Katholieke Universiteit Leuven, Leuven (Belgium); McBride, William H. [Department of Radiation Oncology, University of California at Los Angeles, CA (United States); Haustermans, Karin M. [Department of Radiation Oncology, University Hospitals Leuven Campus Gasthuisberg, Leuven (Belgium)

2011-09-01

153

Malignant plasma cell tumors in human immunodeficiency virus-infected patients.  

PubMed

The development of malignant neoplasms in patients with the acquired immune deficiency syndrome (AIDS) or with a positive human immunodeficiency virus (HIV) antibody test is a well known phenomenon. According to the guidelines from the Centers for Disease Control (Atlanta, GA), the presence of intermediate-grade or high-grade B-cell non-Hodgkin's lymphoma in HIV antibody-positive patients is considered a diagnostic criterion for AIDS. The authors describe two cases of malignant plasma cell tumors in two young HIV-infected patients. In light of this and other reports of plasma cell tumors in patients at risk for AIDS or with a positive HIV antibody test, the finding of another manifestation of B-cell neoplasia in these patients may enlarge the spectrum of AIDS-related tumors. PMID:2369717

Gold, J E; Schwam, L; Castella, A; Pike, S B; Opfell, R; Zalusky, R

1990-07-15

154

Membrane lipids modifications in human gliomas of different degree of malignancy.  

PubMed

A great deal of experimental evidence shows that the growth of tumors is accompanied by significant changes at the expense of the cell surface. For the present paper, we set out to analyse the composition of membrane lipids (cholesterol, phospholipids, neutral and acidic glycosphingolipids, sulphatides) in human cerebral astrocytomas, which is a group of tumors that offer a valid model for the study of the various grades of cellular transformations in vivo. The results obtained in the present study permit us to draw a series of conclusions in relation to the malignancy grade of glial human tumors. In particular, an increase in the malignancy is accompanied by: 1) a reduction of the total lipids, a reduction that involves all the principal classes of lipids of the plasma membrane, for which it has been possible to demonstrate a correlation of an exponential nature, which is significant with the increasing of the histological grading; 2) a gradual accumulation, in the area of glycosphingolipids, of lattosylceramide and GD3, molecules that can constitute a valid marker of the malignancy grade; moreover, the glycolipid composition of astrocytomas of high degree differs from that of tumors of a low grade because of the presence of more complex glycolipids (trihexosylceramide and tetraosylceramide); 3) a gradual increase, in the area of phospholipids, of PC/PE and PC/SM ratios, indices of the microviscosity of the membrane. The data obtained suggest that the profound modifications of membrane lipids, which are gradually accompanied by a progressive increase in the malignancy of the tumor, can, on the one hand, be responsible for functional variations connected with neoplastic growth, and, on the other hand, constitute valuable biochemical parameters which are useful, together with histological studies, in the diagnosis of these tumors. PMID:1323645

Campanella, R

1992-01-01

155

Role of phosphodiesterase 2 in growth and invasion of human malignant melanoma cells.  

PubMed

Cyclic nucleotide phosphodiesterases (PDEs) regulate the intracellular concentrations and effects of adenosine 3',5'-cyclic monophosphate (cAMP) and guanosine 3',5'-cyclic monophosphate (cGMP). The role of PDEs in malignant tumor cells is still uncertain. The role of PDEs, especially PDE2, in human malignant melanoma PMP cell line was examined in this study. In PMP cells, 8-bromo-cAMP, a cAMP analog, inhibited cell growth and invasion. However, 8-bromo-cGMP, a cGMP analog, had little or no effect. PDE2 and PDE4, but not PDE3, were expressed in PMP cells. Growth and invasion of PMP cells were inhibited by erythro-9-(2-hydroxy-3-nonyl) adenine (EHNA), a specific PDE2 inhibitor, but not by rolipram, a specific PDE4 inhibitor. Moreover, cell growth and invasion were inhibited by transfection of small interfering RNAs (siRNAs) specific for PDE2A and a catalytically-dead mutant of PDE2A. After treating cells with EHNA or rolipram, intracellular cAMP concentrations were increased. Growth and invasion were stimulated by PKA14-22, a PKA inhibitor, and inhibited by N(6)-benzoyl-c AMP, a PKA specific cAMP analog, whereas 8-(4-chlorophenylthio)-2'-O-methyl-cAMP, an Epac specific cAMP analog, did not. Invasion, but not growth, was stimulated by A-kinase anchor protein (AKAP) St-Ht31 inhibitory peptide. Based on these results, PDE2 appears to play an important role in growth and invasion of the human malignant melanoma PMP cell line. Selectively suppressing PDE2 might possibly inhibit growth and invasion of other malignant tumor cell lines. PMID:24705027

Hiramoto, Kenichi; Murata, Taku; Shimizu, Kasumi; Morita, Hiroshi; Inui, Madoka; Manganiello, Vincent C; Tagawa, Toshiro; Arai, Naoya

2014-09-01

156

A molecular targeting against nuclear factor-?B, as a chemotherapeutic approach for human malignant mesothelioma.  

PubMed

Chronic inflammation due to the absorption of asbestos is an important cause of mesothelioma. Although the increased prevalence of mesothelioma is a serious problem, the development of effective chemotherapeutic agents remains incomplete. As the nuclear factor-?B (NF-?B) pathway contributes to malignant transformation of various types of cells, we explored NF-?B activity in three different pathological types of malignant mesothelioma cells, and evaluated the therapeutic potential of a recently reported NF-?B inhibitor, IMD-0354. NF-?B was constantly activated in MSTO-211H, NCI-H28, and NCI-H2052 cells, and the proliferation of these cell lines was inhibited by IMD-0354. D-type cyclins were effectively suppressed in mixed tissue type MSTO-211H, leading to cell cycle arrest at sub G1 /G1 phase. IMD-0354 reduced cyclin D3 in both epithelial tissue type NCI-H28 and sarcomatoid tissue type NCI-H2052. In a sphere formation assay, IMD-0354 effectively decreased the number and diameter of MSTO-211H spheres. Preincubation of MSTO-211H cells with IMD-0354 delayed tumor formation in transplanted immunodeficient mice. Furthermore, administration of IMD-0354 markedly rescued the survival rate of mice that received intrathoracic injections of MSTO-211H cells. These results indicate that a targeted drug against NF-?B might have therapeutic efficacy in the treatment of human malignant mesothelioma. PMID:24510578

Nishikawa, Sho; Tanaka, Akane; Matsuda, Akira; Oida, Kumiko; Jang, Hyosun; Jung, Kyungsook; Amagai, Yosuke; Ahn, Ginae; Okamoto, Noriko; Ishizaka, Saori; Matsuda, Hiroshi

2014-04-01

157

L1 adhesion molecule (CD 171) in development and progression of human malignant melanoma.  

PubMed

The L1 adhesion molecule (CD171) plays an important role in axon guidance and cell migration in the nervous system. In the human, L1 is expressed on tumors derived from neurocrest and on certain carcinomas. We have analyzed immunohistochemically L1 expression on paraffin embedded specimens of acquired melanocytic nevi, primary cutaneous melanomas, and cutaneous and lymph node metastases of malignant melanomas. We found an increase in L1 immunoreactivity in malignant melanomas and metastases of malignant melanomas as compared to acquired melanocytic nevi that was statistically significant (P<0.05). Additionally, a correlation of L1 immunoreactivity with histological data of prognostic value such as Clark level and the expression of alphav-integrins was found. We detected soluble L1 in the conditioned medium of cultivated melanoma cells but only in 1/40 serum samples from a panel of melanoma patients representing various stages of disease. Our findings suggest that the presence of L1 might contribute to tumor progression by promoting cell adhesion and migration. PMID:12490317

Fogel, Mina; Mechtersheimer, Sabine; Huszar, Monica; Smirnov, Asya; Abu-Dahi, Adel; Tilgen, Wolfgang; Reichrath, Jörg; Georg, Thomas; Altevogt, Peter; Gutwein, Paul

2003-01-28

158

A molecular targeting against nuclear factor-?B, as a chemotherapeutic approach for human malignant mesothelioma  

PubMed Central

Chronic inflammation due to the absorption of asbestos is an important cause of mesothelioma. Although the increased prevalence of mesothelioma is a serious problem, the development of effective chemotherapeutic agents remains incomplete. As the nuclear factor-?B (NF-?B) pathway contributes to malignant transformation of various types of cells, we explored NF-?B activity in three different pathological types of malignant mesothelioma cells, and evaluated the therapeutic potential of a recently reported NF-?B inhibitor, IMD-0354. NF-?B was constantly activated in MSTO-211H, NCI-H28, and NCI-H2052 cells, and the proliferation of these cell lines was inhibited by IMD-0354. D-type cyclins were effectively suppressed in mixed tissue type MSTO-211H, leading to cell cycle arrest at sub G1/G1 phase. IMD-0354 reduced cyclin D3 in both epithelial tissue type NCI-H28 and sarcomatoid tissue type NCI-H2052. In a sphere formation assay, IMD-0354 effectively decreased the number and diameter of MSTO-211H spheres. Preincubation of MSTO-211H cells with IMD-0354 delayed tumor formation in transplanted immunodeficient mice. Furthermore, administration of IMD-0354 markedly rescued the survival rate of mice that received intrathoracic injections of MSTO-211H cells. These results indicate that a targeted drug against NF-?B might have therapeutic efficacy in the treatment of human malignant mesothelioma.

Nishikawa, Sho; Tanaka, Akane; Matsuda, Akira; Oida, Kumiko; Jang, Hyosun; Jung, Kyungsook; Amagai, Yosuke; Ahn, Ginae; Okamoto, Noriko; Ishizaka, Saori; Matsuda, Hiroshi

2014-01-01

159

Inflammation precedes the development of human malignant mesotheliomas in a SCID mouse xenograft model  

PubMed Central

Asbestos fibers cause chronic inflammation that may be critical to the development of malignant mesothelioma (MM). Two human MM cell lines (Hmeso, PPM Mill) were used in a SCID mouse xenograft model to assess time-dependent patterns of inflammation and tumor formation. After intraperitoneal (IP) injection of MM cells, mice were euthanized at 7, 14, and 30 days, and peritoneal lavage fluid (PLF) was examined for immune cell profiles and human and mouse cytokines. Increases in human MM-derived IL-6, IL-8, bFGF, and VEGF were observed in mice at 7 days postinjection of either MM line, and a striking neutrophilia was observed at all time points. Free-floating tumor spheroids developed in mice at 14 days, and both spheroids and adherent MM tumor masses occurred in all mice at 30 days. Results suggest that inflammation and cytokine production precede and may be critical to the development of MMs.

Hillegass, Jedd M.; Shukla, Arti; Lathrop, Sherrill A.; MacPherson, Maximilian B.; Beuschel, Stacie L.; Butnor, Kelly J.; Testa, Joseph R.; Pass, Harvey I.; Carbone, Michele; Steele, Chad; Mossman, Brooke T.

2010-01-01

160

Enhancement of malignant properties of human osteosarcoma cells with disialyl gangliosides GD2/GD3.  

PubMed

The expression and implications of gangliosides in human osteosarcomas have not been systematically analyzed. In this study, we showed that gangliosides GD3 and GD2 are highly expressed in the majority of human osteosarcoma cell lines derived from oral cavity regions. Introduction of GD3 synthase cDNA into a GD3/GD2-negative (GD3/GD2-) human osteosarcoma subline resulted in the establishment of GD3/GD2+ transfectant cells. They showed increased cell migration and invasion activities in wound healing and Boyden chamber invasion assays, respectively, compared to the control cells. When treated with serum, GD3/GD2+ cells showed stronger tyrosine phosphorylation of p130Cas, focal adhesion kinase, and paxillin than GD3/GD2- cells. In particular, paxillin underwent much stronger phosphorylation, suggesting its role in cell motility. Furthermore, we tried to dissect the roles of GD3 and GD2 in the malignant properties of the transfectant cells by establishing single ganglioside-expressing cells, that is, either GD3 or GD2. Although GD3/GD2+ cells showed the most malignant properties, GD2+ cells showed almost equivalent levels to GD3/GD2+ cells in invasion and migration activities, and in the intensities of tyrosine phosphorylation of paxillin. Among Src family kinases, Lyn was expressed predominantly, and was involved in the invasion and motility of GD3- and/or GD2-expressing transfectants. Furthermore, it was elucidated by gene silencing that Lyn was located in a different pathway from that of FAK to eventually lead paxillin activation. These results suggested that GD2/GD3 are responsible for the enhancement of the malignant features of osteosarcomas, and might be candidate targets in molecular-targeted therapy. PMID:22632091

Shibuya, Hidenobu; Hamamura, Kazunori; Hotta, Hiroshi; Matsumoto, Yasuyuki; Nishida, Yoshihiro; Hattori, Hisashi; Furukawa, Keiko; Ueda, Minoru; Furukawa, Koichi

2012-09-01

161

Response of human malignant melanoma xenografts to hyperthermia: effect of vascular occlusion  

SciTech Connect

Two human malignant melanomas from two patients, grown subcutaneously in the leg of athymic nude mice, were exposed to hyperthermia (42.5/sup o/C) for varying times. Single cell survival was assayed in vitro in soft agar. The sensitivity to heat of the tumor cells was considerably enhanced when the blood supply to the tumors was occluded 15 min before and during treatment. The D/sub 0/-values of the survival curves were 86 min (unclamped) and 13 min (clamped) for E.E. melanoma and 25 min (unclamped) and 11 min (clamped) for V.N. melanoma.

Rofstad, E.K.; Brustad, T.

1981-12-01

162

Ocrelizumab, a humanized monoclonal antibody against CD20 for inflammatory disorders and B-cell malignancies.  

PubMed

Biogen Idec Inc, Genentech Inc, Roche Holding AG and Chugai Pharmaceutical Co Ltd are developing ocrelizumab, a humanized mAb against CD20, for the potential treatment of inflammatory disorders and B-cell malignancies. Ocrelizumab is undergoing phase III clinical trials for rheumatoid arthritis and lupus nephritis, and phase II trials for multiple sclerosis and hematological cancer. Previously, ocrelizumab was also being developed for the treatment of systemic lupus erythematosus (SLE) and neuromyelitis optica; however, development for SLE has been discontinued. No development has been reported for neuromyelitis optica and as of January 2007, this indication had been removed from the company pipeline. PMID:18951300

Hutas, Gabor

2008-11-01

163

Human lung epithelial cells progressed to malignancy through specific oncogenic manipulations  

PubMed Central

We used CDK4/hTERT-immortalized normal human bronchial epithelial cells (HBECs) from several individuals to study lung cancer pathogenesis by introducing combinations of common lung cancer oncogenic changes (p53, KRAS, MYC) and followed the stepwise transformation of HBECs to full malignancy. This model demonstrated that: 1) the combination of five genetic alterations (CDK4, hTERT, sh-p53, KRASV12, and c-MYC) is sufficient for full tumorigenic conversion of HBECs; 2) genetically-identical clones of transformed HBECs exhibit pronounced differences in tumor growth, histology, and differentiation; 3) HBECs from different individuals vary in their sensitivity to transformation by these oncogenic manipulations; 4) high levels of KRASV12 are required for full malignant transformation of HBECs, however prior loss of p53 function is required to prevent oncogene-induced senescence; 5) over-expression of c-MYC greatly enhances malignancy but only in the context of sh-p53+KRASV12; 6) growth of parental HBECs in serum-containing medium induces differentiation while growth of oncogenically manipulated HBECs in serum increases in vivo tumorigenicity, decreases tumor latency, produces more undifferentiated tumors, and induces epithelial-to-mesenchymal transition (EMT); 7) oncogenic transformation of HBECs leads to increased sensitivity to standard chemotherapy doublets; 8) an mRNA signature derived by comparing tumorigenic vs. non-tumorigenic clones was predictive of outcome in lung cancer patients. Collectively, our findings demonstrate this HBEC model system can be used to study the effect of oncogenic mutations, their expression levels, and serum-derived environmental effects in malignant transformation, while also providing clinically translatable applications such as development of prognostic signatures and drug response phenotypes.

Sato, Mitsuo; Larsen, Jill E.; Lee, Woochang; Sun, Han; Shames, David S.; Dalvi, Maithili P.; Ramirez, Ruben D.; Tang, Hao; DiMaio, J. Michael; Gao, Boning; Xie, Yang; Wistuba, Ignacio I.; Gazdar, Adi F.; Shay, Jerry W.; Minna, John D.

2013-01-01

164

A Tissue Graft Model of DNA Damage Response in the Normal and Malignant Human Prostate  

PubMed Central

Purpose DNA damage responses are relevant to prostate cancer initiation, progression and treatment. Few models of the normal and malignant human prostate that maintain stromal-epithelial interactions in vivo exist in which to study DNA damage responses. We evaluated the feasibility of maintaining tissue slice grafts at subcutaneous vs subrenal capsular sites in RAG2?/? ?C?/? mice to study the DNA damage responses of normal and malignant glands. Materials and Methods We compared the take rate and histology of tissue slice grafts from fresh, precision cut surgical specimens that were maintained for 1 to 4 weeks in subcutaneous vs subrenal capsular sites. Induction of ?H2AX, p53, ATM and apoptosis was evaluated as a measure of the DNA damage response after irradiation. Results The take rate of subcutaneous tissue slice grafts was higher than typically reported but lower than at the subrenal capsular site. Subcutaneous tissue slice grafts frequently showed basal cell hyperplasia, squamous meta-plasia and cystic atrophy, and cancer did not survive. In contrast, normal and malignant histology was well maintained in subrenal capsular tissue slice grafts. Regardless of implantation site the induction of ?H2AX and ATM occurred in tissue slice graft epithelium 1 hour after irradiation and decreased to basal level by 24 hours, indicating DNA damage recognition and repair. As observed previously in prostatic ex vivo models, p53 was not activated. Notably, tumor but not normal cells responded to irradiation by undergoing apoptosis. Conclusions To our knowledge this is the first study of DNA damage responses in a patient derived prostate tissue graft model. The subrenal capsular site of RAG2?/? ?C ?/? mice optimally maintains normal and malignant histology and function, permitting novel studies of DNA damage responses in a physiological context.

af Hallstrom, Taija M.; Zhao, Hongjuan; Tian, Junqiang; Rantanen, Ville; Reese, Stephen W.; Nolley, Rosalie; Laiho, Marikki; Peehl, Donna M.

2014-01-01

165

RAF antisense oligonucleotide as a tumor radiosensitizer  

Microsoft Academic Search

The RAF-1 serine–threonine kinase plays a central role in signal transduction pathways involved in cell survival and proliferation. The concept of RAF-1-targeted disruption of cell signaling for therapeutic purposes was first advanced in 1989 with the demonstration of tumor growth inhibition in athymic mice and radiosensitization of human squamous carcinoma cells transfected with a vector expressing antisense cDNA. However, the

Usha Kasid; Anatoly Dritschilo

2003-01-01

166

Immunohistochemical expression of the glucose transporters Glut-1 and Glut-3 in human malignant melanomas and benign melanocytic lesions  

PubMed Central

Background Reported data indicate that cancer cells have increased rates of glucose metabolism, as determined by 18FDG-PET imaging in patients with malignancies. The results of many studies have demonstrated that the expression of glucose transporters, especially Glut-1, is increased in a variety of malignancies. This study was undertaken to assess the differential expression of Glut-1 and Glut-3 by benign and malignant melanocytic lesions. Methods Immunohistochemical staining for Glut-1 and Glut-3 was performed on paraffin-embedded tissue sections prepared from melanocytic nevi (12 cases), Spitz nevi (12 cases) and primary cutaneous malignant melanomas (20 cases). Results We observed immunoreactivity for Glut-1 in all melanocytic nevi, 9 of the 12 Spitz nevi and in 9 of the 20 malignant melanomas, whereas Glut-3 was expressed in all the melanocytic lesions, both benign and malignant. Conclusion These findings indicate that the glucose transporters Glut-1 and Glut-3 play a role in the glucose metabolism of melanocytic cells. Glut-1 was present in the majority of benign nevi, whereas its expression was downregulated in 55% of malignant melanomas. Our results suggest that glucose transporter Glut-1 expression can significantly discriminate between human malignant melanoma and benign melanocytic nevi, and support the idea that additional mechanisms other than Glut-1 may contribute to glucose uptake in melanomas.

Parente, Paola; Coli, Antonella; Massi, Guido; Mangoni, Antonella; Fabrizi, Manuela M; Bigotti, Giulio

2008-01-01

167

Selective growth inhibition of human malignant melanoma cells by syringic acid-derived proteasome inhibitors  

PubMed Central

Background It has been shown that proteasome inhibition leads to growth arrest in the G1 phase of the cell cycle and/or induction of apoptosis. However, it was found that some of these inhibitors do not induce apoptosis in several human normal cell lines. This selective activity makes proteasome inhibition a promising target for new generation of anticancer drugs. Clinical validation of the proteasome, as a therapeutic target in oncology, has been provided by the dipeptide boronic acid derivative; bortezomib. Bortezomib has proven to be effective as a single agent in multiple myeloma and some forms of non-Hodgkin’s lymphoma. Syringic acid (4-hydroxy-3,5-dimethoxybenzoic acid, 1), a known phenolic acid, was isolated from the methanol extract of Tamarix aucheriana and was shown to possess proteasome inhibitory activity. Methods Using Surflex-Dock program interfaced with SYBYL, the docking affinities of syringic acid and its proposed derivatives to 20S proteasome were studied. Several derivatives were virtually proposed, however, five derivatives: benzyl 4-hydroxy-3,5-dimethoxybenzoate (2), benzyl 4-(benzyloxy)-3,5-dimethoxybenzoate (3), 3'-methoxybenzyl 3,5-dimethoxy-4-(3'-methoxybenzyloxy)benzoate (4), 3'-methoxybenzyl 4-hydroxy-3,5-dimethoxybenzoate (5) and 3',5'-dimethoxybenzyl 4-hydroxy-3,5-dimethoxybenzoate (6), were selected based on high docking scores, synthesized, and tested for their anti-mitogenic activity against human colorectal, breast and malignant melanoma cells as well as normal human fibroblast cells. Results Derivatives 2, 5, and 6 showed selective dose-dependent anti-mitogenic effect against human malignant melanoma cell lines HTB66 and HTB68 with minimal cytotoxicity on colorectal and breast cancer cells as well as normal human fibroblast cells. Derivatives 2, 5 and 6 significantly (p???0.0001) inhibited the various proteasomal chymotrypsin, PGPH, and trypsin like activities. They growth arrested the growth of HTB66 cells at G1 and G2-phases. They also arrested the growth of HTB68 cells at S- and G2-phase, respectively. Moreover, derivatives 2, 5, and 6 markedly induced apoptosis (? 90%) in both HTB66 and HTB68. Conclusions Computer-derived syringic acid derivatives possess selective anti-mitogenic activity on human malignant melanoma cells that may be attributed to perturbation of cell cycle, induction of apoptosis and inhibition of various 26S proteasomal activities.

2013-01-01

168

Growth and Spread of Human Malignant T Lymphoblasts in Immunosuppressed Nude Mice: A Model for Meningeal Leukemia  

Microsoft Academic Search

Previous work has shown that nude (nu\\/nu) mice addition- ally immunosuppressed by splenectomy, sublethal irradia- tion, and treatment with antiasialo GMI antiserum (SIA- nu\\/nu mice) have no detectable natural killer activity and allow the growth of human malignant lymphoblasts. We show here that all SIA-nulnu mice engrafted intravenously with 5 x 108 malignant lymphoblasts originally derived from a child with

Federica Cavallo; Marco Forni; Carlo Riccardi; Antonio Soleti; Francesco Di Pierro; Guido Forni

1992-01-01

169

Secreted Frizzled-related proteins inhibit motility and promote growth of human malignant glioma cells.  

PubMed

Cellular resistance to multiple proapoptotic stimuli and invasion of surrounding brain tissue by migrating tumor cells are main obstacles to an effective therapy for human malignant glioma. Here, we report that the Wnt family of embryonic differentiation genes modulate growth of malignant glioma cells in vitro and in vivo and inhibit cellular migration in vitro. sFRPs (soluble Frizzled-related proteins) are soluble proteins that bind to Wnt and interfere with Wnt signaling. We find that sFRP-1 and sFRP-2 are produced by the majority of longterm and ex vivo malignant glioma cell lines. Glioma cells that ectopically express sFRPs exhibit increased clonogenicity and enhanced resistance to serum starvation. In contrast, sFRPs do not modulate glioma cell susceptibility to apoptosis induced by the cytotoxic cytokines, CD95 (Fas/APO-1) ligand (CD95L) or Apo2 ligand/tumor necrosis factor-related apoptosis-inducing ligand (Apo2L/TRAIL), or various cytotoxic drugs. sFRP-2 strongly promotes the growth of intracranial glioma xenografts in nude mice. In contrast, enhanced expression of sFRPs inhibits the motility of glioma cells in vitro. sFRP-mediated effects on glioma cells are accompanied by decreased expression and activity of matrix metalloproteinase-2 (MMP-2) and decreased tyrosine phosphorylation of beta-catenin. Thus, sFRPs promote survival under non-supportive conditions and inhibit the migration of glioma cells. We suggest that the regulation of these cellular processes involves expression of MMP-2 and tyrosine phosphorylation of beta-catenin. These data support a function for Wnt signaling and its modulation by sFRPs in the biology of human gliomas. Oncogene (2000) 19, 4210 - 4220 PMID:10980594

Roth, W; Wild-Bode, C; Platten, M; Grimmel, C; Melkonyan, H S; Dichgans, J; Weller, M

2000-08-31

170

Syntenic Relationships between Genomic Profiles of Fiber-Induced Murine and Human Malignant Mesothelioma  

PubMed Central

Malignant mesothelioma (MM) is an aggressive tumor with a poor prognosis mainly linked to past asbestos exposure. Murine models of MM based on fiber exposure have been developed to elucidate the mechanism of mesothelioma formation. Genomic alterations in murine MM have now been partially characterized. To gain insight into the pathophysiology of mesothelioma, 16 murine and 35 human mesotheliomas were characterized by array-comparative genomic hybridization and were screened for common genomic alterations. Alteration of the 9p21 human region, often by biallelic deletion, was the most frequent alteration in both species, in agreement with the CDKN2A/CDKN2B locus deletion in human disease and murine models. Other shared aberrations were losses of 1p36.3–p35 and 13q14–q33 and gains of 5p15.3–p13 regions. However, some differences were noted, such as absence of recurrent alterations in mouse regions corresponding to human chromosome 22. Comparison between altered recurrent regions in asbestos-exposed and non–asbestos-exposed patients showed a significant difference in the 14q11.2–q21 region, which was also lost in fiber-induced murine mesothelioma. A correlation was also demonstrated between genomic instability and tumorigenicity of human mesothelioma xenografts in nude mice. Overall, these data show similarities between murine and human disease, and contribute to the understanding of the influence of fibers in the pathogenesis of mesothelioma and validation of the murine model for preclinical testing.

Jean, Didier; Thomas, Emilie; Manie, Elodie; Renier, Annie; de Reynies, Aurelien; Lecomte, Celine; Andujar, Pascal; Fleury-Feith, Jocelyne; Galateau-Salle, Francoise; Giovannini, Marco; Zucman-Rossi, Jessica; Stern, Marc-Henri; Jaurand, Marie-Claude

2011-01-01

171

Gene expression profiling of mouse p53-deficient epidermal carcinoma defines molecular determinants of human cancer malignancy  

Microsoft Academic Search

BACKGROUND: The epidermal specific ablation of Trp53 gene leads to the spontaneous development of aggressive tumors in mice through a process that is accelerated by the simultaneous ablation of Rb gene. Since alterations of p53-dependent pathway are common hallmarks of aggressive, poor prognostic human cancers, these mouse models can recapitulate the molecular features of some of these human malignancies. RESULTS:

Ramón García-Escudero; Ana B Martínez-Cruz; Mirentxu Santos; Corina Lorz; Carmen Segrelles; Guillermo Garaulet; Cristina Saiz-Ladera; Clotilde Costa; Águeda Buitrago-Pérez; Marta Dueñas; Jesús M Paramio

2010-01-01

172

BAX frameshift mutations in cell lines derived from human haemopoietic malignancies are associated with resistance to apoptosis and microsatellite instability  

Microsoft Academic Search

Bax suppresses tumorigenesis in a mouse model system and Bax-deficient mice exhibit lymphoid hyperplasia suggesting that BAX functions as a tumour suppressor in human haemopoietic cells. We examined BAX expression in 20 cell lines derived from human haemopoietic malignancies and consistent with a potential tumour suppressor function, identified two cell lines, DG75 (a Burkitt lymphoma cell line) and Jurkat (a

Matthew Brimmell; Rezzeline Mendiola; Jonathan Mangion; Graham Packham

1998-01-01

173

Expression levels of the DNA repair enzyme HAP1 do not correlate with the radiosensitivities of human or HAP1-transfected rat cell lines  

PubMed Central

Apurinic/apyrimidinic (AP) sites in DNA are potentially lethal and mutagenic. They can arise spontaneously or following DNA damage from reactive oxygen species or alkylating agents, and they constitute a significant product of DNA damage following cellular exposure to ionizing radiation. The major AP endonuclease responsible for initiating the repair of these and other DNA lesions in human cells is HAP1, which also possesses a redox function. We have determined the cellular levels of this enzyme in 11 human tumour and fibroblast cell lines in relation to clonogenic survival following ionizing radiation. Cellular HAP1 levels and surviving fraction at 2 Gy (SF2) varied five- and tenfold respectively. However, no correlation was found between these two parameters following exposure to ?-irradiation at low (1.1 cGy per min) or high (108 cGy per min) dose rates. To examine this further, wild-type and mutant versions of HAP1 were overexpressed, using an inducible HAP1 cDNA expression vector system, in the rat C6 glioma cell line which has low endogenous AP endonuclease activity. Induction of wild-type HAP1 expression caused a > fivefold increase in the capacity of cellular extracts to cleave an oligonucleotide substrate containing a single abasic site, but increased expression did not confer increased resistance to ?-irradiation at high- or low-dose rates, or to the methylating agent methyl methanesulphonate (MMS). Expression in C6 cell lines of mutant forms of HAP1 deleted for either the redox activator or DNA repair functions displayed no apparent titrational or dominant negative effects. These studies suggest that the levels of endogenous AP endonuclease activities in the various cell lines examined are not limiting for efficient repair in cells following exposure to ionizing radiation or MMS. This contrasts with the correlation we have found between HAP1 levels and radiosensitivity in cervix carcinomas (Herring et al (1998) Br J Cancer 78: 1128–1133), indicating that HAP1 levels in this case assume a critical survival role and hence that established cell lines might not be a suitable model for such studies. © 1999 Cancer Research Campaign

Herring, C J; Deans, B; Elder, R H; Rafferty, J A; MacKinnon, J; Barzilay, G; Hickson, I D; Hendry, J H; Margison, GP

1999-01-01

174

Relationship between DNA double-strand break rejoining and cell survival after exposure to ionizing radiation in human fibroblast strains with differing ATM/p53 status: Implications for evaluation of clinical radiosensitivity  

SciTech Connect

Purpose: To better understand the impact of defects in the DNA damage-surveillance network on the various cell-based assays used for the prediction of patient radiosensitivity. Methods and Materials: We examined noncancerous human fibroblast strains from individuals with ataxia telangiectasia (ataxia telangiectasia mutated [ATM] deficient) or Li-Fraumeni syndrome (p53 deficient) using the neutral comet, H2AX phosphorylation, and clonogenic survival assays. Results: Using the comet assay, we found that, compared with normal fibroblasts, cells lacking either ATM or p53 function exhibited a reduced rate of double-strand break (DSB) rejoining early ({<=}4 h) after exposure to 8 Gy of {gamma}-radiation and also exhibited high levels of unrejoined DSBs later after irradiation. ATM-deficient and p53-deficient fibroblasts also exhibited abnormally increased levels of phosphorylated H2AX ({gamma}-H2AX) at later intervals after irradiation. In the clonogenic assay, ATM-deficient cells exhibited marked radiosensitivity and p53-deficient cells had varying degrees of radioresistance compared with normal fibroblasts. Conclusion: Regardless of whether ataxia telangiectasia and Li-Fraumeni syndrome fibroblasts are DSB-repair deficient per se, it is apparent that p53 and ATM defects greatly influence the cellular phenotype as evidenced by the neutral comet and {gamma}-H2AX assays. Our data suggest that the {gamma}-H2AX levels observed at later intervals after irradiation may represent a reliable measure of the overall DSB rejoining capabilities of human fibroblasts. However, it appears that using this parameter as a predictor of radiosensitivity without knowledge of the cells' p53 status could lead to incorrect conclusions.

Mirzayans, Razmik [Department of Oncology, University of Alberta, Cross Cancer Institute, Edmonton, Alberta (Canada); Severin, Diane [Department of Oncology, University of Alberta, Cross Cancer Institute, Edmonton, Alberta (Canada); Murray, David [Department of Oncology, University of Alberta, Cross Cancer Institute, Edmonton, Alberta (Canada)]. E-mail: davem@cancerboard.ab.ca

2006-12-01

175

Two canine malignant vascular tumours with features of human retiform haemangioendothelioma.  

PubMed

Within the human medical literature, retiform haemangioendothelioma (RHE) is an established and well-recognized histopathological variant of endothelial tumours, but to date RHE has not been reported in animals. These tumours are characterized by the presence of elongate, arborizing vascular channels lined by neoplastic endothelium with prominent, often bulging ('hobnail') nuclei supported by a dense collagenous matrix and accompanied by abundant lymphoplasmacytic inflammation. Immunohistochemically, the neoplastic cells typically express endothelial markers such as von Willebrand factor and CD31. Human RHEs are categorized as low-grade malignancies. This report describes two canine vascular tumours with features consistent with RHE. In both cases there was suspected or known widespread tumour metastasis. PMID:22817764

Lombardini, E D; Summers, B A

2013-02-01

176

Electron paramagnetic resonance spectrometry and imaging in melanomas: comparison between pigmented and nonpigmented human malignant melanomas.  

PubMed

It has been known for a long time that the melanin pigments present in normal skin, hair, and most of malignant melanomas can be detected by electron paramagnetic resonance (EPR) spectrometry. In this study, we used EPR imaging as a tool to map the concentration of melanin inside ex vivo human pigmented and nonpigmented melanomas and correlated this cartography with anatomopathology. We obtained accurate mappings of the melanin inside pigmented human melanoma samples. The signal intensity observed on the EPR images correlated with the concentration of melanin within the tumors, visible on the histologic sections. In contrast, no EPR signal coming from melanin was observed from nonpigmented melanomas, therefore demonstrating the absence of EPR-detectable pigments inside these particular cases of skin cancer and the importance of pigmentation for further EPR imaging studies on melanoma. PMID:23651499

Godechal, Quentin; Ghanem, Ghanem E; Cook, Martin G; Gallez, Bernard

2013-06-01

177

Characterization of phosphodiesterase 2A in human malignant melanoma PMP cells  

PubMed Central

The prognosis for malignant melanoma is poor; therefore, new diagnostic methods and treatment strategies are urgently needed. Phosphodiesterase 2 (PDE2) is one of 21 phosphodiesterases, which are divided into 11 families (PDE1-PDE11). PDE2 hydrolyzes cyclic AMP (cAMP) and cyclic GMP (cGMP), and its binding to cGMP enhances the hydrolysis of cAMP. We previously reported the expression of PDE1, PDE3 and PDE5 in human malignant melanoma cells. However, the expression of PDE2 in these cells has not been investigated. Herein, we examined the expression of PDE2A and its role in human oral malignant melanoma PMP cells. Sequencing of RT-PCR products revealed that PDE2A2 was the only variant expressed in PMP cells. Four point mutations were detected; one missense mutation at nucleotide position 734 (from C to T) resulted in the substitution of threonine with isoleucine at amino acid position 214. The other three were silent mutations. An in vitro migration assay and a terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling assay revealed that suppressing PDE2 activity with its specific inhibitor, erythro-9-(2-hydroxy-3-nonyl)-adenine (EHNA), had no impact on cell motility or apoptosis. Furthermore, the cytotoxicity of EHNA, assessed using a trypan blue exclusion assay, was negligible. On the other hand, assessment of cell proliferation by BrdU incorporation and cell cycle analysis by flow cytometry revealed that EHNA treatment inhibited DNA synthesis and increased the percentage of G2/M-arrested cells. Furthermore, cyclin A mRNA expression was downregulated, while cyclin E mRNA expression was upregulated in EHNA-treated cells. Our results demonstrated that the PDE2A2 variant carrying point mutations is expressed in PMP cells and may affect cell cycle progression by modulating cyclin A expression. Thus, PDE2A2 is a possible new molecular target for the treatment of malignant melanoma.

MORITA, HIROSHI; MURATA, TAKU; SHIMIZU, KASUMI; OKUMURA, KENYA; INUI, MADOKA; TAGAWA, TOSHIRO

2013-01-01

178

Malignant transformation of human bronchial epithelial cells by radon-simulated alpha-particles.  

PubMed

Epidemiological studies have shown that inhalation of radon is associated with an increased risk for bronchogenic carcinoma in uranium miners. These alpha-emitting radon daughters also represent the largest component of background radiation to the general public. In the present study, the oncogenic transforming effects of single versus multiple doses of radon-simulated alpha-particles were examined using human papillomavirus-immortalized human bronchial epithelial cells. Endpoints such as growth kinetics, resistance to serum and 12-O-tetradecanoylphorbol-13-acetate-induced terminal differentiation, anchorage-independent growth and tumorigenicity in nude mice were used to assess the various stages of transformation in the bronchial epithelial cells. We show here, for the first time, that immortalized human cells in culture can be malignantly transformed by a single 30 cGy dose of alpha-particles. Transformed cells produced progressively growing subcutaneous tumors upon inoculation into athymic nude mice. Immunofluorescent staining of keratin and isozyme analysis of the cell lines subsequently generated from these tumors indicated that the cells were of human epithelial origin. Analysis of genomic DNA from the tumorigenic cell lines using PCR amplification and restriction enzyme analysis demonstrated no point mutation at either codon 12/13 or 61 in any of the ras oncogenes examined (K-, N- and H-ras). This system provides an opportunity to study the cellular and molecular changes at the various stages in radiation carcinogenesis involving human cells. PMID:8118924

Hei, T K; Piao, C Q; Willey, J C; Thomas, S; Hall, E J

1994-03-01

179

The role of cell cycle redistribution in radiosensitization: Implications regarding the mechanism of fluorodeoxyuridine radiosensitization  

SciTech Connect

Radiosensitization has previously been demonstrated in a human colon cancer cell line (HT-29) following a 2 h exposure to low, clinically relevant concentrations (0.05-0.5 {mu}M) of fluorodeoxyuridine (FdUrd) (15). The sensitizer enhancement ratio value (measured at 10% survival) plateaued at {approx} 1.7 between 16 and 32 h following removal of drug. Parallel studies investigating the effect of FdUrd on the distribution of cells throughout the cell cycle found that the percentage of cells in early S-phase increased to {approx} 70% during the same period that maximal radiosensitization was noted. As a follow-up to these findings, experiments have been designed to investigate the contribution of this early S-phase delay to radiosensitization. Synchronized populations of Ht-29 cells have been obtained with three separate techniques. Two involve the induction of a reversible metaphase arrest J(with high pressure N{sub 2}O or colcemid) followed by a shakeoff of mitotic cells. The third uses a plant amino acid, mimosine, to induce a reversible block at the G{sub 1}/S boundary. Flow cytometry was used to analyze the degree of synchrony based on bromodeoxyuridine (BrdUrd) uptake and propidium iodide (PI) staining. Radiation survival curves were obtained on these synchronized populations to investigate changes in radiosensitivity through the cell cycle. Additionally, levels of thymidylate synthase (TS), the primary target of FdUrd cytotoxicity, were measured in each phase of the cell cycle using the TS 106 monoclonal antibody against human TS. Synchronization with mitotic shakeoff produced relatively pure populations of cells in G{sub 1}; however, the degree of synchrony in early S-phase was limited both by cells remaining in G;{sub 1} and by cells progressing into late S-phase. These techniques failed to reveal increased radiosensitivity in early S-phase at 10% survival. 36 refs., 4 figs., 2 tabs.

McGinn, C.J.; Kunugi, fK.A.; Kinsella, T.J. [Univ. of Wisconsin Medical School, Madison, WI (United States)] [and other

1994-11-15

180

Alterations in oncogene expression and radiosensitivity in the most frequently used SV40-transformed human skin fibroblasts.  

PubMed

In comparison with primary cell cultures, SV40-transformed human skin fibroblasts, either from healthy donors or from patients suffering from ataxia-telangiectasia (AT) or xeroderma pigmentosum, are more resistant to the cytotoxic action of low LET 60cobalt gamma-rays as well as to high LET alpha-particles. Resistance factors calculated from D10's lie between 1.4 and 2.0. Northern blot analysis reveals spontaneous overexpression of the oncogenes c-myc, Ki-ras and c-raf and of the tumour suppressor gene p53 as a consequence of SV40 transformation. For c-myc, the increased expression is due to gene amplification and gene rearrangement. An even further increase in the expression of c-myc has been found for AT cells (AT5BI-VA) after moderate doses of 60cobalt gamma-irradiation. A possible correlation between SV40-induced changes in gene expression and cellular radioresistance is discussed. PMID:7912716

Lücke-Huhle, C

1994-06-01

181

Radioprotection of Human Cell Nuclear DNA by Polyamines: Radiosensitivity of Chromatin is Influenced by Tightly Bound Spermine  

NASA Technical Reports Server (NTRS)

The polyamines putrescine (PUT) and spermine (SPM) were examined for their ability to protect human cell Deoxyribonucleic Acid (DNA) against the formation of radiation-induced double-strand breaks (DSBs). As observed previously, under conditions where polyamines were shown to be almost completely absent, association with nuclear matrix protein into a nucleoid, and organization into chromatin structure, protected DNA from induction of DSBs by factors of 4.5 and 95, respectively. At concentrations below 1 mM, PUT or SPM provided equivalent levels of protection to deproteinized nuclear DNA, consistent with their capacity to scavenge radiation-induced radicals. At constant ionic strength, 5 mM SPM protected deproteinized DNA and nucleoid DNA and DNA in nuclear chromatin by factors of 100 and 26, respectively. At 5 mM, SPM provided 15 times greater protection of deproteinized DNA than did PUT. Under physiologically relevant conditions, 5 mM SPM protected DNA in the intact nucleus from the induction of DSBs by a factor of 2 relative to DNA in the absence of SPM. Studies of SPM binding during cellular fractionation revealed that a significant fraction of the cellular SPM is tightly bound in the nucleus but can be removed by extended washing. Thus the association of SPM with nuclear chromatin appears to be a significant contributor to the resistance of the cell's DNA to the induction of DSBs.

Warters, Raymond L.; Newton, Gerald L.; Olive, Peggy L.; Fahey, Robert C.

1999-01-01

182

Integration of Principles of Systems Biology and Radiation Biology: Toward Development of in silico Models to Optimize IUdR-Mediated Radiosensitization of DNA Mismatch Repair Deficient (Damage Tolerant) Human Cancers  

PubMed Central

Over the last 7?years, we have focused our experimental and computational research efforts on improving our understanding of the biochemical, molecular, and cellular processing of iododeoxyuridine (IUdR) and ionizing radiation (IR) induced DNA base damage by DNA mismatch repair (MMR). These coordinated research efforts, sponsored by the National Cancer Institute Integrative Cancer Biology Program (ICBP), brought together system scientists with expertise in engineering, mathematics, and complex systems theory and translational cancer researchers with expertise in radiation biology. Our overall goal was to begin to develop computational models of IUdR- and/or IR-induced base damage processing by MMR that may provide new clinical strategies to optimize IUdR-mediated radiosensitization in MMR deficient (MMR?) “damage tolerant” human cancers. Using multiple scales of experimental testing, ranging from purified protein systems to in vitro (cellular) and to in vivo (human tumor xenografts in athymic mice) models, we have begun to integrate and interpolate these experimental data with hybrid stochastic biochemical models of MMR damage processing and probabilistic cell cycle regulation models through a systems biology approach. In this article, we highlight the results and current status of our integration of radiation biology approaches and computational modeling to enhance IUdR-mediated radiosensitization in MMR? damage tolerant cancers.

Kinsella, Timothy J.; Gurkan-Cavusoglu, Evren; Du, Weinan; Loparo, Kenneth A.

2011-01-01

183

Intrinsic radiosensitivity of human pancreatic tumour cells and the radiosensitising potency of the nitric oxide donor sodium nitroprusside.  

PubMed Central

A panel of eight human pancreatic tumour cell lines displayed high intrinsic radioresistance, with mean inactivation doses between 2.4 and 6.5 Gy, similar to those reported for melanoma and glioblastoma. The radiosensitising potency of sodium nitroprusside, a bioreductive nitric oxide donor, was assessed in a model of metabolism-induced hypoxia in a cell micropellet. Sodium nitroprusside at 0.1 mM revealed a radiosensitising effect with an overall enhancement ratio of 1.9 compared with 2.5 for oxygen. Radiosensitising activity correlated with the enhancement of single-strand DNA breakage caused by radiation. In suspensions with cell densities of between 3% and 30% (v/v), the half-life of sodium nitroprusside decreased from 31 to 3.2 min, suggesting a value of around 1 min for micropellets. Despite this variation, the radiosensitising activity was similar in micropellets and in diluted cell suspensions. S-nitroso-L-glutathione was found to possess radiosensitising activity, consistent with a possible role of natural thiols in the storing of radiobiologically active nitric oxide adducts derived from sodium nitroprusside. As measured by a nitric oxide-specific microsensor, activation of sodium nitroprusside occurred by bioreduction, whereas S-nitroso-L-glutathione showed substantial spontaneous decomposition. Both agents appear to exert radiosensitising action through nitric oxide as its scavenging by carboxy phenyltetramethylimidazolineoxyl N-oxide (carboxy-PTI0) and oxyhaemoglobin resulted in attenuated radiosensitisation. Sodium nitroprusside was at least 10-fold more potent than etanidazole, a 2-nitroimidazole used as a reference. Our data suggest that sodium nitroprusside, a drug currently used for the treatment of hypertension, is a potential tumour radioresponse modifier.

Verovski, V. N.; Van den Berge, D. L.; Soete, G. A.; Bols, B. L.; Storme, G. A.

1996-01-01

184

Periostin accelerates human malignant melanoma progression by modifying the melanoma microenvironment.  

PubMed

Given no reliable therapy for advanced malignant melanoma, it is important to elucidate the molecular mechanisms underlying the disease progression. Using a quantitative proteomics approach, the 'isobaric tags for relative and absolute quantitation (iTRAQ)' method, we identified that the extracellular matrix protein, periostin (POSTN), was highly expressed in invasive melanoma compared with normal skin. An immunohistochemical analysis showed that POSTN was expressed in all invasive melanoma (n = 20) and metastatic lymph node (n = 5) tissue samples, notably restricted in their stroma. In terms of the intercellular regulation of POSTN, we found that there was upregulation of POSTN when melanoma cells and normal human dermal fibroblasts (NHDFs) were cocultured, with restricted expression of TGF-?1 and TGF-?3. In a functional analyses, recombinant and NHDF-derived POSTN significantly accelerated melanoma cell proliferation via the integrin/mitogen-activated protein kinase (MAPK) signaling pathway in vitro. The size of implanted melanoma tumors was significantly suppressed in POSTN/Rag2 double knockout mice compared with Rag2 knock-out mice. These results indicate that NHDF-derived POSTN accelerates melanoma progression and might be a promising therapeutic target for malignant melanoma. PMID:24674392

Kotobuki, Yorihisa; Yang, Lingli; Serada, Satoshi; Tanemura, Atsushi; Yang, Fei; Nomura, Shintaro; Kudo, Akira; Izuhara, Kenji; Murota, Hiroyuki; Fujimoto, Minoru; Katayama, Ichiro; Naka, Tetsuji

2014-07-01

185

p16(INK4a) -mediated suppression of telomerase in normal and malignant human breast cells.  

PubMed

The cyclin-dependent kinase inhibitor p16(INK4a) (CDKN2A) is an important tumor suppressor gene frequently inactivated in human tumors. p16 suppresses the development of cancer by triggering an irreversible arrest of cell proliferation termed cellular senescence. Here, we describe another anti-oncogenic function of p16 in addition to its ability to halt cell cycle progression. We show that transient expression of p16 stably represses the hTERT gene, encoding the catalytic subunit of telomerase, in both normal and malignant breast epithelial cells. Short-term p16 expression increases the amount of histone H3 trimethylated on lysine 27 (H3K27) bound to the hTERT promoter, resulting in transcriptional silencing, likely mediated by polycomb complexes. Our results indicate that transient p16 exposure may prevent malignant progression in dividing cells by irreversible repression of genes, such as hTERT, whose activity is necessary for extensive self-renewal. PMID:20569236

Bazarov, Alexey V; Van Sluis, Marjolein; Hines, William C; Bassett, Ekaterina; Beliveau, Alain; Campeau, Eric; Mukhopadhyay, Rituparna; Lee, Won Jae; Melodyev, Sonya; Zaslavsky, Yuri; Lee, Leonard; Rodier, Francis; Chicas, Agustin; Lowe, Scott W; Benhattar, Jean; Ren, Bing; Campisi, Judith; Yaswen, Paul

2010-10-01

186

P16INK4a MEDIATED SUPPRESSION OF TELOMERASE IN NORMAL AND MALIGNANT HUMAN BREAST CELLS  

PubMed Central

Summary The cyclin-dependent kinase inhibitor p16INK4a (CDKN2A) is an important tumor-suppressor gene frequently inactivated in human tumors. p16 suppresses the development of cancer by triggering an irreversible arrest of cell proliferation termed cellular senescence. Here, we describe another anti-oncogenic function of p16 in addition to its ability to halt cell cycle progression. We show that transient expression of p16 stably represses the hTERT gene, encoding the catalytic subunit of telomerase, in both normal and malignant breast epithelial cells. Short-term p16 expression increases the amount of histone H3 trimethylated on lysine 27 (H3K27) bound to the hTERT promoter, resulting in transcriptional silencing, likely mediated by polycomb complexes. Our results indicate that transient p16 exposure may prevent malignant progression in dividing cells by irreversible repression of genes, such as hTERT, whose activity is necessary for extensive self-renewal.

Bazarov, Alexey V.; van Sluis, Marjolein; Hines, Curtis; Bassett, Ekaterina; Beliveau, Alain; Campeau, Eric; Mukhopadhyay, Rituparna; Lee, Won Jae; Melodyev, Sonya; Zaslavsky, Yuri; Lee, Leonard; Rodier, Francis; Chicas, Agustin; Lowe, Scott W.; Benhattar, Jean; Ren, Bing; Campisi, Judith; Yaswen, Paul

2010-01-01

187

Proteomic and bioinformatic analysis of mammalian SWI/SNF complexes identifies extensive roles in human malignancy.  

PubMed

Subunits of mammalian SWI/SNF (mSWI/SNF or BAF) complexes have recently been implicated as tumor suppressors in human malignancies. To understand the full extent of their involvement, we conducted a proteomic analysis of endogenous mSWI/SNF complexes, which identified several new dedicated, stable subunits not found in yeast SWI/SNF complexes, including BCL7A, BCL7B and BCL7C, BCL11A and BCL11B, BRD9 and SS18. Incorporating these new members, we determined mSWI/SNF subunit mutation frequency in exome and whole-genome sequencing studies of primary human tumors. Notably, mSWI/SNF subunits are mutated in 19.6% of all human tumors reported in 44 studies. Our analysis suggests that specific subunits protect against cancer in specific tissues. In addition, mutations affecting more than one subunit, defined here as compound heterozygosity, are prevalent in certain cancers. Our studies demonstrate that mSWI/SNF is the most frequently mutated chromatin-regulatory complex (CRC) in human cancer, exhibiting a broad mutation pattern, similar to that of TP53. Thus, proper functioning of polymorphic BAF complexes may constitute a major mechanism of tumor suppression. PMID:23644491

Kadoch, Cigall; Hargreaves, Diana C; Hodges, Courtney; Elias, Laura; Ho, Lena; Ranish, Jeff; Crabtree, Gerald R

2013-06-01

188

Clonal selection in xenografted human T cell acute lymphoblastic leukemia recapitulates gain of malignancy at relapse  

PubMed Central

Genomic studies in human acute lymphoblastic leukemia (ALL) have revealed clonal heterogeneity at diagnosis and clonal evolution at relapse. In this study, we used genome-wide profiling to compare human T cell ALL samples at the time of diagnosis and after engraftment (xenograft) into immunodeficient recipient mice. Compared with paired diagnosis samples, the xenograft leukemia often contained additional genomic lesions in established human oncogenes and/or tumor suppressor genes. Mimicking such genomic lesions by short hairpin RNA–mediated knockdown in diagnosis samples conferred a selective advantage in competitive engraftment experiments, demonstrating that additional lesions can be drivers of increased leukemia-initiating activity. In addition, the xenograft leukemias appeared to arise from minor subclones existing in the patient at diagnosis. Comparison of paired diagnosis and relapse samples showed that, with regard to genetic lesions, xenograft leukemias more frequently more closely resembled relapse samples than bulk diagnosis samples. Moreover, a cell cycle– and mitosis-associated gene expression signature was present in xenograft and relapse samples, and xenograft leukemia exhibited diminished sensitivity to drugs. Thus, the establishment of human leukemia in immunodeficient mice selects and expands a more aggressive malignancy, recapitulating the process of relapse in patients. These findings may contribute to the design of novel strategies to prevent or treat relapse.

Clappier, Emmanuelle; Gerby, Bastien; Sigaux, Francois; Delord, Marc; Touzri, Farah; Hernandez, Lucie; Ballerini, Paola; Baruchel, Andre

2011-01-01

189

Frequency analysis of multispectral photoacoustic images for differentiating malignant region from normal region in excised human prostate  

NASA Astrophysics Data System (ADS)

Frequency domain analysis of the photoacoustic (PA) radio frequency signals can potentially be used as a tool for characterizing microstructure of absorbers in tissue. This study investigates the feasibility of analyzing the spectrum of multiwavelength PA signals generated by excised human prostate tissue samples to differentiate between malignant and normal prostate regions. Photoacoustic imaging at five different wavelengths, corresponding to peak absorption coefficients of deoxyhemoglobin, whole blood, oxyhemoglobin, water and lipid in the near infrared (NIR) (700 nm - 1000 nm) region, was performed on freshly excised prostate specimens taken from patients undergoing prostatectomy for biopsy confirmed prostate cancer. The PA images were co-registered with the histopathology images of the prostate specimens to determine the region of interest (ROI) corresponding to malignant and normal tissue. The calibrated power spectrum of each PA signal from a selected ROI was fit to a linear model to extract the corresponding slope, midband fit and intercept parameters. The mean value of each parameter corresponding to malignant and adjacent normal prostate ROI was calculated for each of the five wavelengths. The results obtained for 9 different human prostate specimens, show that the mean values of midband fit and intercept are significantly different between malignant and normal regions. In addition, the average midband fit and intercept values show a decreasing trend with increasing wavelength. These preliminary results suggest that frequency analysis of multispectral PA signals can be used to differentiate malignant region from the adjacent normal region in human prostate tissue.

Sinha, Saugata; Rao, Navalgund A.; Valluru, Keerthi S.; Chinni, Bhargava K.; Dogra, Vikram S.; Helguera, Maria

2014-03-01

190

Chromosomes, cancer and radiosensitivity  

SciTech Connect

Some specific chromosomal abnormalities are associated with certain cancers. The earliest description of such a specific association is the one of the Philadelphia chromosome and myelogenous leukemia (1960). Other congenital karyotype abnormalities are associated with specific cancers. Examples of these are Down's syndrome with leukemia and Klinefelter's syndrome with male breast cancer. Genetic diseases of increased chromosome breakage, or of defective chromosome repair, are associated with greatly increased cancer incidence. Three such diseases have been recognized: 1) Fanconi's anemia, associated with leukemias and lymphomas, 2) Bloom's syndrome, associated with acute leukemias and lymphosarcoma, and 3) ataxia telangiectasia, associated with Hodgkin's disease, leukemia, and lymphosarcomas. Ten percent of individuals with ataxia telangiectasia will develop one of these neoplasms. Individuals with certain of these syndromes display an unusually high radiosensitivity. Radiation therapy for cancers has been fatal in patients who received as low as 3000 rad. This remarkable radiosensitivity has been quantitated in cell cultures from such cases. Evidence suggests that the apparent sensitivity may reflect subnormal ability to repair radiation damage. The rapid proliferation of information in this field stems from the interdigitation of many disciplines and specialties, including cytogenetics, cell biology, molecular biology, epidemiology, radiobiology, and several others. This paper is intended for clinicians; it presents a structured analytic scheme for correlating and classifying this multidisciplinary information as it becomes available.

Samouhos, E.

1983-08-01

191

Detection of malignant lesions in human colonic mucosa by digital imaging of laser-induced autofluorescence  

NASA Astrophysics Data System (ADS)

We report the results of feasibility studies on using digital imaging of the laser-induced autofluorescence of colonic tissues for a detection of premalignant and malignant lesions of human colon. Images of the autofluorescence excited with 325 nm line of He-Cd laser were recorded in vitro in six regions of a visible spectrum using a CCD camera. A total of 126 areas on 30 tissue specimens was examined. At all the spectral bands selected the intensity of the fluorescence of the neoplastic tissues was lower than that of the normal mucosa. The ratio R of the intensities of the autofluorescence of normal and abnormal tissues measured with the 440 nm filter was found to be a sensitive diagnostic parameter for detecting adenocarcinomas. This parameter is less sensitive in detecting adenomatous polyps and does not differentiate polyps with different degrees of dysplasia.

Chwirot, B. W.; Chwirot, S.; Jedrzejczyk, W.; Michniewicz, Z.; Raczynska, A. M.; Modrak, M.

2001-07-01

192

Understanding the role of NRF2-regulated miRNAs in human malignancies.  

PubMed

Nuclear factor (erythroid-derived 2)-like 2 (NRF2) is a key transcription factor that regulates the expression of over a hundred cytoprotective and antioxidant genes that provide cellular protection from reactive oxygen species. Chemotherapy resistance in several cancers has been linked to dysregulation of the NRF2 signalling pathway, moreover there is growing evidence that NRF2 may contribute to tumorigenesis. MicroRNA (miRNA) are small non-coding RNA sequences that post-transcriptionally regulate mRNA sequences. In cancer pathogenesis, aberrantly expressed miRNAs can act as either tumor suppressor or oncogenic miRNA. Recent evidence has been described that identifies a number of miRNA that can be regulated by NRF2. This review outlines the importance of NRF2 in regulating miRNA, and the functional role this may have in the tumorigenesis of human malignancies and their chemotherapy resistance. PMID:24029073

Shah, Niraj M; Rushworth, Stuart A; Murray, Megan Y; Bowles, Kristian M; MacEwan, David J

2013-08-01

193

Understanding the role of NRF2-regulated miRNAs in human malignancies  

PubMed Central

Nuclear factor (erythroid-derived 2)-like 2 (NRF2) is a key transcription factor that regulates the expression of over a hundred cytoprotective and antioxidant genes that provide cellular protection from reactive oxygen species. Chemotherapy resistance in several cancers has been linked to dysregulation of the NRF2 signalling pathway, moreover there is growing evidence that NRF2 may contribute to tumorigenesis. MicroRNA (miRNA) are small non-coding RNA sequences that post-transcriptionally regulate mRNA sequences. In cancer pathogenesis, aberrantly expressed miRNAs can act as either tumor suppressor or oncogenic miRNA. Recent evidence has been described that identifies a number of miRNA that can be regulated by NRF2. This review outlines the importance of NRF2 in regulating miRNA, and the functional role this may have in the tumorigenesis of human malignancies and their chemotherapy resistance.

Shah, Niraj M; Rushworth, Stuart A; Murray, Megan Y; Bowles, Kristian M; MacEwan, David J

2013-01-01

194

FTIR microscopic comparative study on normal, premalignant, and malignant tissues of human intenstine  

NASA Astrophysics Data System (ADS)

Fourier-Transform Infrared Spectroscopy (FTIR) employs a unique approach to optical diagnosis of tissue pathology based on the characteristic molecular vibrational spectra of the tissue. The architectural changes in the cellular and sub-cellular levels developing in abnormal tissue, including a majority of cancer forms, manifest themselves in different optical signatures, which can be detected in infrared spectroscopy. The biological systems we have studied include normal, premalignant (polyp) and malignant human colonic tissues from three patients. Our method is based on microscopic infrared study (FTIR-microscopy) of thin tissue specimens and a direct comparison with normal histopathological analysis, which serves as a `gold' reference. The normal intestine tissue has a stronger absorption than polyp and cancerous types over a wide region in all three cases. The detailed analysis showed that there is a significant decrease in total phosphate and creatine contents for polyp and cancerous tissue types in comparison to the controls.

Mordechai, Shaul; Argov, Shmuel; Salman, Ahmad O.; Cohen, Beny; Ramesh, Jagannathan; Erukhimovitch, Vitaly; Goldstein, Jed; Sinelnikov, Igor

2000-07-01

195

Human Telomerase Reverse Transcriptase Promoter Regulation in Normal and Malignant Human Ovarian Epithelial Cells1  

Microsoft Academic Search

The telomerase RNA-protein complex responsible for maintenance of telomeric DNA at chromosome ends, is usually inactive in most primary somatic human cells, but is specifically activated with in vitro immortal- ization and during tumorigenesis. Although expression of the RNA com- ponent of telomerase appears to be constitutive, the expression pattern of human telomerase reverse transcriptase (hTERT), the catalytic subunit of

Ilana Braunstein; Orit Cohen-Barak; Catherine Shachaf; Yael Ravel; Michal Yalon-Hacohen; Gordon B. Mills; Maty Tzukerman; Karl L. Skorecki

196

Targeting human B-cell malignancies through Ig light chain specific cytotoxic T lymphocytes  

PubMed Central

Purpose The variable regions of Ig (idiotype, Id) expressed by malignant B cells can be used as tumor-specific antigens that induce humoral and cellular immunity. However, epitopes derived from Id that stimulate human CD8+ T-cell immunity are incompletely characterized. Experimental design The clonal Ig VL of human myeloma cell line U266 and five primary B-cell tumors were sequenced and peptides corresponding to the Ig VL region were tested for their ability to stimulate cytotoxic T lymphocytes (CTLs) from ten HLA-A* 0201 positive normal donors. The CTLs thus generated were tested against peptide-pulsed T2 cells and autologous tumor cells. Results 14 peptides derived from Ig light chain (VL) of U266 and primary B-cell tumors were used to generate 68 Cytotoxic T lymphocytes (CTLs) lines that specifically produced IFN-? when co-cultured with peptide-pulsed T2 cells. These CTLs lysed peptide-pulsed T2 cell as well as U266 or autologous tumor targets in an HLA class I-dependent manner. Sequence analysis revealed shared VL T-cell epitopes in U266 and primary B-cell tumors, not previously reported within Ig heavy chain (VH) sequences. Conclusion This study thus identifies novel immunogenic CTLs epitopes from Id VL, suggests that they are naturally presented on the surface of B-cell malignancies, and supports their inclusion in next generation Id vaccines. The ability to prime T cells derived from normal HLA-matched donors, rather than patients, also may have direct application to current strategies, designed to generate allogeneic tumor-specific T cells for adoptive transfer.

Weng, Jinsheng; Cha, Soung-Chul; Matsueda, Satoko; Alatrash, Gheath; Popescu, Michael S.; Yi, Qing; Molldrem, Jeffrey J; Wang, Michael; Neelapu, Sattva S.; Kwak, Larry W.

2011-01-01

197

Role of malignant ascites on human mesothelial cells and their gene expression profiles  

PubMed Central

Background Malignant ascites is often present at diagnostic in women with advanced ovarian cancer (OC) and its presence is associated with a worse outcome. Human peritoneal mesothelial cells (HPMCs) are key components of malignant ascites. Although the interplay between HPMCs and OC cells is believed to be critical for tumor progression, it has not been well characterized. The purpose of this study was to assess the effect of ascites on HPMCs and clarify the role of HPMCs in OC progression. Methods Human OC ascites and benign peritoneal fluids were assessed for their ability to stimulate HPMC proliferation. Conditioned medium from ascites- and benign fluid-stimulated HPMCs were compared for their ability to attenuate apoptosis induced by TNF-related apoptosis-inducing ligand (TRAIL). We conducted a comparative analysis of global expression changes in ascites-stimulated HPMCs using Agilent oligonucleotide microarrays. Results As compared to benign peritoneal fluids, malignant ascites stimulated the proliferation of HPMCs. TRAIL-induced apoptosis was attenuated in OC cells exposed to conditioned medium from ascites-stimulated HPMCs as compared to OC cells exposed to conditioned medium from benign fluid-stimulated HPMCs. A total of 649 genes were differentially expressed in ascites-stimulated HPMCs. Based on a ratio of more than 1.5-fold and a P?

2014-01-01

198

Optical delineation of human malignant melanoma using second harmonic imaging of collagen  

PubMed Central

Skin cancer incidence has increased exponentially over the last three decades. In 2008 skin cancer caused 2280 deaths in the UK, with 2067 due to malignant melanoma. Early diagnosis can prevent mortality, however, conventional treatment requires multiple procedures and increasing treatment times. Second harmonic generation (SHG) imaging could offer diagnosis and demarcation of melanoma borders non-invasively at presentation thereby short-cutting the excision biopsy stage. To test the efficacy and accuracy of SHG imaging of collagen in skin and to delineate the borders of skin cancers, unstained human melanoma biopsy sections were imaged using SHG microscopy. Comparisons with sister sections, stained with H&E or Melan-A were made for correlation of invasion borders. Fresh ex vivo normal human and rat skin was imaged through its whole thickness using SHG to demonstrate this technique is transferable to in vivo tissues. SHG imaging demonstrated detailed collagen distribution in normal skin, with total absence of SHG signal (fibrillar collagen) within the melanoma-invaded tissue. The presence or absence of signal changes dramatically at the borders of the melanoma, accurately demarcating the edges that strongly correlated with H&E and Melan-A defined borders (p<0.002). SHG imaging of ex vivo human and rat skin demonstrated collagen architecture could be imaged through the full thickness of the skin. We propose that SHG imaging could be used for diagnosis and accurate demarcation of melanoma borders on presentation and therefore potentially reduce mortality rates.

Thrasivoulou, C.; Virich, G.; Krenacs, T.; Korom, I.; Becker, D. L.

2011-01-01

199

Cell cycle checkpoint status in human malignant mesothelioma cell lines: response to gamma radiation  

PubMed Central

Knowledge of the function of the cell cycle checkpoints in tumour cells may be important to develop treatment strategies for human cancers. The protein p53 is an important factor that regulates cell cycle progression and apoptosis in response to drugs. In human malignant mesothelioma, p53 is generally not mutated, but may be inactivated by SV40 early region T antigen (SV40 Tag). However, the function of p53 has not been investigated in mesothelioma cells. Here, we investigated the function of the cell cycle checkpoints in six human mesothelioma cell lines (HMCLs) by studying the cell distribution in the different phases of the cell cycle by flow cytometry, and expression of cell cycle proteins, p53, p21WAF1/CIP1 and p27KIP1. In addition, we studied p53 gene mutations and expression of SV40 Tag. After exposure to ?-radiation, HMCLs were arrested either in one or both phases of the cell cycle, demonstrating a heterogeneity in cell cycle control. G1 arrest was p21WAF1/CIP1- and p53-dependent. Lack of arrest in G1 was not related to p53 mutation or binding to SV40 Tag, except in one HMCL presenting a missense mutation at codon 248. These results may help us to understand mesothelioma and develop new treatments.

Vivo, C; Lecomte, C; Levy, F; Leroy, K; Kirova, Y; Renier, A; Kheuang, L; Piedbois, P; Chopin, D; Jaurand, M C

2003-01-01

200

Two types of human malignant melanoma cell lines revealed by expression patterns of mitochondrial and survival-apoptosis genes: implications for malignant melanoma therapy.  

PubMed

Human malignant melanoma has poor prognosis because of resistance to apoptosis and therapy. We describe identification of the expression profile of 1,037 mitochondria-focused genes and 84 survival-apoptosis genes in 21 malignant melanoma cell lines and 3 normal melanocyte controls using recently developed hMitChip3 cDNA microarrays. Unsupervised hierarchical clustering analysis of 1,037 informative genes, and 84 survival-apoptosis genes, classified these malignant melanoma cell lines into type A (n = 12) and type B (n = 9). Three hundred fifty-five of 1,037 (34.2%) genes displayed significant (P ? 0.030; false discovery rate ? 3.68%) differences (± ? 2.0-fold) in average expression, with 197 genes higher and 158 genes lower in type A than in type B. Of 84 genes with known survival-apoptosis functions, 38 (45.2%) displayed the significant (P < 0.001; false discovery rate < 0.15%) difference. Antiapoptotic (BCL2, BCL2A1, PPARD, and RAF1), antioxidant (MT3, PRDX5, PRDX3, GPX4, GLRX2, and GSR), and proapoptotic (BAD, BNIP1, APAF1, BNIP3L, CASP7, CYCS, CASP1, and VDAC1) genes expressed at higher levels in type A than in type B, whereas the different set of antiapoptotic (PSEN1, PPP2CA, API5, PPP2R1B, PPP2R1A, and FIS1), antioxidant (HSPD1, GSS, SOD1, ATOX1, and CAT), and proapoptotic (ENDOG, BAK1, CASP2, CASP4, PDCD5, HTRA2, SEPT4, TNFSF10, and PRODH) genes expressed at lower levels in type A than in type B. Microarray data were validated by quantitative reverse transcription-PCR. These results showed the presence of two types of malignant melanoma, each with a specific set of dysregulated survival-apoptosis genes, which may prove useful for development of new molecular targets for therapeutic intervention and novel diagnostic biomarkers for treatment and prognosis of malignant melanoma. PMID:19383853

Su, David M; Zhang, Qiuyang; Wang, Xuexi; He, Ping; Zhu, Yuelin Jack; Zhao, Jianxiong; Rennert, Owen M; Su, Yan A

2009-05-01

201

Two types of human malignant melanoma cell lines revealed by expression patterns of mitochondrial and survival-apoptosis genes: implications for malignant melanoma therapy  

PubMed Central

Human malignant melanoma has poor prognosis because of resistance to apoptosis and therapy. We describe identification of the expression profile of 1,037 mitochondria-focused genes and 84 survival-apoptosis genes in 21 malignant melanoma cell lines and 3 normal melanocyte controls using recently developed hMitChip3 cDNA micro-arrays. Unsupervised hierarchical clustering analysis of 1,037 informative genes, and 84 survival-apoptosis genes, classified these malignant melanoma cell lines into type A (n = 12) and type B (n = 9). Three hundred fifty-five of 1,037 (34.2%) genes displayed significant (P ? 0.030; false discovery rate ? 3.68%) differences (±?2.0-fold) in average expression, with 197 genes higher and 158 genes lower in type A than in type B. Of 84 genes with known survival-apoptosis functions, 38 (45.2%) displayed the significant (P < 0.001; false discovery rate < 0.15%) difference. Antiapoptotic (BCL2, BCL2A1, PPARD, and RAF1), antioxidant (MT3, PRDX5, PRDX3, GPX4, GLRX2, and GSR), and proapoptotic (BAD, BNIP1, APAF1, BNIP3L, CASP7, CYCS, CASP1, and VDAC1) genes expressed at higher levels in type A than in type B, whereas the different set of antiapoptotic (PSEN1, PPP2CA, API5, PPP2R1B, PPP2R1A, and FIS1), antioxidant (HSPD1, GSS, SOD1, ATOX1, and CAT), and proapoptotic (ENDOG, BAK1, CASP2, CASP4, PDCD5, HTRA2, SEPT4, TNFSF10, and PRODH) genes expressed at lower levels in type A than in type B. Microarray data were validated by quantitative reverse transcription-PCR. These results showed the presence of two types of malignant melanoma, each with a specific set of dysregulated survival-apoptosis genes, which may prove useful for development of new molecular targets for therapeutic intervention and novel diagnostic biomarkers for treatment and prognosis of malignant melanoma.

Su, David M.; Zhang, Qiuyang; Wang, Xuexi; He, Ping; Zhu, Yuelin Jack; Zhao, Jianxiong; Rennert, Owen M.; Su, Yan A.

2011-01-01

202

Restoration of the Expression of Transports Associated with Antigen Processing in Human Malignant Melanoma Increases Tumor-Specific Immunity  

Microsoft Academic Search

The transporter associated with antigen processing (TAP) is essential for peptide delivery from the cytosol into the lumen of the endoplasmic reticulum (ER), where these peptides are loaded on HLA I molecules. Our previous study found that expressions of TAP were reduced in human malignant melanoma (MM) lesions and associated with histopathologic characteristics. In this study, we further investigate expressions

Juan Tao; Yan Li; Ye-Qiang Liu; Lin Wang; Jing Yang; Jing Dong; Yan Wu; Guan-Xin Shen; Ya-Ting Tu

2008-01-01

203

c-RET Molecule in Malignant Melanoma from Oncogenic RET-Carrying Transgenic Mice and Human Cell Lines  

PubMed Central

Malignant melanoma is one of the most aggressive cancers and its incidence worldwide has been increasing at a greater rate than that of any other cancer. We previously reported that constitutively activated RFP-RET-carrying transgenic mice (RET-mice) spontaneously develop malignant melanoma. In this study, we showed that expression levels of intrinsic c-Ret, glial cell line-derived neurotrophic factor (Gdnf) and Gdnf receptor alpha 1 (Gfra1) transcripts in malignant melanomas from RET-transgenic mice were significantly upregulated compared with those in benign melanocytic tumors. These results suggest that not only introduced oncogenic RET but also intrinsic c-Ret/Gdnf are involved in murine melanomagenesis in RET-mice. We then showed that c-RET and GDNF transcript expression levels in human malignant melanoma cell lines (HM3KO and MNT-1) were higher than those in primary cultured normal human epithelial melanocytes (NHEM), while GFRa1 transcript expression levels were comparable among NHEM, HM3KO and MNT-1. We next showed c-RET and GFRa1 protein expression in HM3KO cells and GDNF-mediated increased levels of their phosphorylated c-RET tyrosine kinase and signal transduction molecules (ERK and AKT) sited potentially downstream of c-RET. Taken together with the finding of augmented proliferation of HM3KO cells after GDNF stimulation, our results suggest that GDNF-mediated c-RET kinase activation is associated with the pathogenesis of malignant melanoma.

Takeda, Kozue; Iida, Machiko; Kumasaka, Mayuko; Matsumoto, Yoshinari; Kato, Masashi

2010-01-01

204

Horizontal transmission and retention of malignancy, as well as functional human genes, after spontaneous fusion of human glioblastoma and hamster host cells in vivo.  

PubMed

Cell fusion in vitro has been used to study cancer, gene mapping and regulation, and the production of antibodies via hybridomas. However, in-vivo heterosynkaryon formation by cell-cell fusion has received less attention. This investigation describes the spontaneous fusion of a human glioblastoma with normal hamster cells after xenogeneic transplantation, resulting in malignant cells that express both human and hamster genes and gene products, and retention of glioblastoma traits with an enhanced ability to metastasize. Three of 7 human genes found showed translation of their proteins during serial propagation in vivo or in vitro for years; namely, CD74, CXCR4 and PLAGL2, each implicated with malignancy or glioblastoma. This supports the thesis that genetic hybridization of cancer and normal cells can transmit malignancy and also, as first described herein, regulatory genes involved in the tumor's organotypic morphology. Evidence also is increasing that even cell-free human cancer DNA can induce malignancy and transfer genetic information to normal cells. Hence, we posit that the transfer of genetic information between tumor and stromal cells, whether by cell-cell fusion or other mechanisms, is implicated in the progression of malignancy, and may further define the crosstalk between cancer cells and their stromal neighbors. PMID:21796629

Goldenberg, David M; Zagzag, David; Heselmeyer-Haddad, Kerstin M; Berroa Garcia, Lissa Y; Ried, Thomas; Loo, Meiyu; Chang, Chien-Hsing; Gold, David V

2012-07-01

205

The claudin family of proteins in human malignancy: a clinical perspective  

PubMed Central

Tight junctions, or zonula occludens, are the most apical component of the junctional complex and provide one form of cell–cell adhesion in epithelial and endothelial cells. Nearly 90% of malignant tumors are derived from the epithelium. Loss of cell–cell adhesion is one of the steps in the progression of cancer to metastasis. At least three main tight junction family proteins have been discovered: occludin, claudin, and junctional adhesion molecule (JAM). Claudins are the most important structural and functional components of tight junction integral membrane proteins, with at least 24 members in mammals. They are crucial for the paracellular flux of ions and small molecules. Overexpression or downregulation of claudins is frequently observed in epithelial-derived cancers. However, molecular mechanisms by which claudins affect tumorigenesis remain largely unknown. As the pivotal proteins in epithelial cells, altered expression and distribution of different claudins have been reported in a wide variety of human malignancies, including pancreatic, colonic, lung, ovarian, thyroid, prostate, esophageal, and breast cancers. In this review, we will give the readers an overall picture of the changes in claudin expression observed in various cancers and their mechanisms of regulation. Downregulation of claudins contributes to epithelial transformation by increasing the paracellular permeability of nutrients and growth factors to cancerous cells. In the cases of upregulation of claudin expression, the barrier function of the cancerous epithelia changes, as they often display a disorganized arrangement of tight junction strands with increased permeability to paracellular markers. Finally, we will summarize the literature suggesting that claudins may become useful biomarkers for cancer detection and diagnosis as well as possible therapeutic targets for cancer treatment.

Ding, Lei; Lu, Zhe; Lu, Qun; Chen, Yan-Hua

2013-01-01

206

Preclinical studies identify novel targeted pharmacological strategies for treatment of human malignant pleural mesothelioma  

PubMed Central

The incidence of human malignant pleural mesothelioma (hMPM) is still increasing worldwide. hMPM prognosis is poor even if the median survival time has been slightly improved after the introduction of the up-to-date chemotherapy. Nevertheless, large phase II/III trials support the combination of platinum derivatives and pemetrexed or raltitrexed, as preferred first-line schedule. Better understanding of the molecular machinery of hMPM will lead to the design and synthesis of novel compounds targeted against pathways identified as crucial for hMPM cell proliferation and spreading. Among them, several receptors tyrosine kinase show altered activity in subsets of hMPM. This observation suggests that these kinases might represent novel therapeutic targets in this chemotherapy-resistant disease. Over these foundations, several promising studies are ongoing at preclinical level and novel molecules are currently under evaluation as well. Yet, established tumour cell lines, used for decades to investigate the efficacy of anticancer agents, although still the main source of drug efficacy studies, after long-term cultures tend to biologically diverge from the original tumour, limiting the predictive potential of in vivo efficacy. Cancer stem cells (CSCs), a subpopulation of malignant cells capable of self-renewal and multilineage differentiation, are believed to play an essential role in cancer initiation, growth, metastasization and relapse, being responsible of chemo- and radiotherapy refractoriness. According to the current carcinogenesis theory, CSCs represent the tumour-initiating cell (TIC) fraction, the only clonogenic subpopulation able to originate a tumour mass. Consequently, the recently described isolation of TICs from hMPM, the proposed main pharmacological target for novel antitumoural drugs, may contribute to better dissect the biology and multidrug resistance pathways controlling hMPM growth.

Favoni, Roberto E; Daga, Antonio; Malatesta, Paolo; Florio, Tullio

2012-01-01

207

Aberrant Expression of Interleukin-1? and Inflammasome Activation in Human Malignant Gliomas  

PubMed Central

Objective Glioblastoma is the most frequent and malignant form of primary brain tumor with grave prognosis. Mounting evidence supports that chronic inflammation (such as chronic overactivation of IL-1 system) is a crucial event in carcinogenesis and tumor progression. IL-1 also is an important cytokine with species-dependent regulations and roles in CNS cell activation. While much attention is paid to specific anti-tumor immunity, little is known about the role of chronic inflammation/innate immunity in glioma pathogenesis. In this study, we examined whether human astrocytic cells (including malignant gliomas) can produce IL-1 and its role in glioma progression. Methods We used a combination of cell culture, real-time PCR, ELISA, western blot, immunocytochemistry, siRNA and plasmid transfection, micro-RNA analysis, angiogenesis (tube formation) assay, and neurotoxicity assay. Results Glioblastoma cells produced large quantities of IL-1 when activated, resembling macrophages/microglia. The activation signal was provided by IL-1 but not the pathogenic components LPS or poly IC. Glioblastoma cells were highly sensitive to IL-1 stimulation, suggesting its relevance in vivo. In human astrocytes, IL-1? mRNA was not translated to protein. Plasmid transfection also failed to produce IL-1 protein, suggesting active repression. Suppression of microRNAs that can target IL-1?/? did not induce IL-1 protein. Glioblastoma IL-1? processing occurred by the NLRP3 inflammasome, and ATP and nigericin increased IL-1? processing by upregulating NLRP3 expression, similar to macrophages. RNAi of annexin A2, a protein strongly implicated in glioma progression, prevented IL-1 induction, demonstrating its new role in innate immune activation. IL-1 also activated Stat3, a transcription factor crucial in glioma progression. IL-1 activated glioblastoma-conditioned media enhanced angiogenesis and neurotoxicity. Conclusions Our results demonstrate unique, species-dependent immune activation mechanisms involving human astrocytes and astrogliomas. Specifically, the ability to produce IL-1 by glioblastoma cells may confer them a mesenchymal phenotype including increased migratory capacity, unique gene signature and proinflammatory signaling.

Tarassishin, Leonid; Casper, Diana; Lee, Sunhee C.

2014-01-01

208

Epigenetic regulation of vitamin D hydroxylase expression and activity in normal and malignant human prostate cells.  

PubMed

It was previously suggested that the 25-Vitamin-D3-1alpha-hydroxylase (CYP27B1) is downregulated during human prostate tumor pathogenesis while the catabolic 25-Vitamin-D3-24-hydroxylase (CYP24) expression is increased. The latter could lead to resistance against the antimitotic, pro-differentiating activity of 1,25-dihydroxycholecalciferol. Our hypothesis was that regulation of Vitamin D hydroxylase expression during prostate tumor progression might be under epigenetic control. We demonstrate by real time RT-PCR that PNT-2 human normal prostate cells indeed possess CYP27B1, but are practically devoid of CYP24 mRNA, whereas DU-145 cancer cells have constitutive expression of CYP24, and very low levels of CYP27B1 mRNA. Treatment of PNT-2 cells with the methylation inhibitor 5-aza-2'-deoxycytidine together with the deacetylation inhibitor trichostatin A resulted in elevation of both CYP27B1 and CYP24 mRNA expression demonstrating that even in normal human prostate cells expression of Vitamin D hydroxylases may be under epigenetic control. In the DU-145 malignant cell line trichostatin A together with 5-aza-2'-deoxycytidine increased CYP27B1 mRNA expression to a smaller extent than in normal cells, however this resulted in a highly significant increase in 1alpha-hydroxylation capacity. This demonstrates for the first time that synthesis of 1,25-dihydroxycholecalciferol in human prostate tumors could be reinitiated by epigenetic regulators. PMID:15860259

Khorchide, Maya; Lechner, Daniel; Cross, Heide S

2005-02-01

209

Downregulation of nuclear receptor FXR is associated with multiple malignant clinicopathological characteristics in human hepatocellular carcinoma  

PubMed Central

The nuclear receptor farnesoid X receptor (FXR) acts as a liver protector by regulating normal liver homeostasis. Spontaneously developed liver tumors have been found in FXR-null mice. However, the role of FXR in the tumorigenesis of human hepatocellular carcinoma (HCC) is still poorly understood. In this study, we measured the expression of FXR and its primary target gene, small heterodimer partner, and analyzed the clinical significance of FXR expression in HCC patients. A lentiviral vector that selectively overexpresses FXR was used to investigate the function of FXR in HCC cell proliferation both in vitro and in vivo. Our data showed that in human HCC, FXR expression was significantly reduced and was positively correlated with multiple malignant clinicopathological characteristics. Lentivirus-mediated exogenous FXR expression resulted in a marked increase of small heterodimer partner expression, significant repression of liver cancer cell proliferation, and tumor growth in nude mice. These results suggest that FXR may be of clinical and pharmacological importance as a promising biomarker of HCC.

Su, Hongying; Ma, Chuang; Liu, Jingfeng; Li, Ningbo; Gao, Meiqin; Huang, Aimin; Wang, Xichun; Huang, Wendong

2012-01-01

210

Polymorphisms in the syntaxin 17 gene are not associated with human cutaneous malignant melanoma.  

PubMed

The prevalence of cutaneous malignant melanoma (CMM) has increased significantly in most Caucasian populations in recent decades. Both genetic and environmental risk factors are involved in the development of CMM. A germline mutation in the syntaxin 17 (STX17) gene of horses was recently identified, which causes premature hair graying and is associated with susceptibility to melanoma. We hypothesized that common germline variants in the STX17 gene might be associated with a predisposition to human CMM or might interact with other melanoma risk genes. We genotyped 26 tagging single nucleotide polymorphisms (SNPs) across the STX17 gene region in an Australian sample of 1560 melanoma cases and 1650 controls and performed logistic regression analysis to identify potential SNP interactions in a combined dataset. Our results do not support an association between CMM and any of the STX17 SNPs and provide no evidence for interactions between the melanoma risk SNP rs910873 on chromosome 20 and any of the STX17 SNPs. We conclude that common variants in the STX17 gene region do not play a key role in the pathogenesis of human melanoma. PMID:19209086

Zhao, Zhen Zhen; Duffy, David L; Thomas, Shane A; Martin, Nicholas G; Hayward, Nicholas K; Montgomery, Grant W

2009-04-01

211

Distinct patterns of hypoxic expression of carbonic anhydrase IX (CA IX) in human malignant glioma cell lines  

Microsoft Academic Search

The hypoxia-inducible enzyme carbonic anhydrase IX (CA IX) has recently been discussed as a surrogate marker of tumor hypoxia,\\u000a an indicator of prognosis and a potential therapeutic target in malignant glioma. To characterize patterns of expression of\\u000a CA IX in human malignant glioma cells, we studied CA IX protein, CA9 mRNA and hypoxia-inducible factor-1? (HIF-1?) protein\\u000a levels in U87-MG, U251,

Harun M. Said; Adrian Staab; Carsten Hagemann; Giles H. Vince; Astrid Katzer; Michael Flentje; Dirk Vordermark

2007-01-01

212

Loss of Canonical Smad4 Signaling Promotes KRAS Driven Malignant Transformation of Human Pancreatic Duct Epithelial Cells and Metastasis  

PubMed Central

Pancreatic ductal adenocarcinoma (PDAC) is the fourth most common cause of cancer death in North America. Activating KRAS mutations and Smad4 loss occur in approximately 90% and 55% of PDAC, respectively. While their roles in the early stages of PDAC development have been confirmed in genetically modified mouse models, their roles in the multistep malignant transformation of human pancreatic duct cells have not been directly demonstrated. Here, we report that Smad4 represents a barrier in KRAS-mediated malignant transformation of the near normal immortalized human pancreatic duct epithelial (HPDE) cell line model. Marked Smad4 downregulation by shRNA in KRASG12V expressing HPDE cells failed to cause tumorigenic transformation. However, KRAS-mediated malignant transformation occurred in a new HPDE-TGF-? resistant (T?R) cell line that completely lacks Smad4 protein expression and is resistant to the mito-inhibitory activity of TGF-?. This transformation resulted in tumor formation and development of metastatic phenotype when the cells were implanted orthotopically into the mouse pancreas. Smad4 restoration re-established TGF-? sensitivity, markedly increased tumor latency by promoting apoptosis, and decreased metastatic potential. These results directly establish the critical combination of the KRAS oncogene and complete Smad4 inactivation in the multi-stage malignant transformation and metastatic progression of normal human HPDE cells.

Leung, Lisa; Radulovich, Nikolina; Zhu, Chang-Qi; Wang, Dennis; To, Christine; Ibrahimov, Emin; Tsao, Ming-Sound

2013-01-01

213

Ectopic Over-expression of Oncogene Pim-2 Induce Malignant Transformation of Nontumorous Human Liver Cell Line L02  

PubMed Central

In order to prove that ectopic over-expression of Pim-2 could induce malignant transformation of human liver cell line L02, three groups of cells were set up including human liver cell line L02 (L02), L02 cells transfected with Pim-2 gene (L02/Pim-2) and L02 cells transfected with empty-vector (L02/Vector). Pim-2 expression levels were detected. The morphology, proliferation level, apoptosis rate and migration ability of the cells were detected respectively. Then the cells were subcutaneously inoculated into athymic mice and the microstructures of the neoplasm were observed. Compared with the controls, Pim-2 expression levels were significantly higher in L02/Pim-2 cells (P<0.05), and their morphology had obvious malignant changes. They also showed a significantly increased proliferation rate (P<0.05) and migration capacity (P<0.05), as well as a significantly decreased apoptosis rate (P<0.05). Only the athymic mice inoculated with L02/Pim-2 cells could generate neoplasm, and the morphology of the neoplasm coincided with that of the hepatoma. The results manifest that ectopic Pim-2 gene could be stably expressed in L02/Pim-2 cells. Both the morphological and biological changes of L02/Pim-2 cells demonstrate the trend of malignant transformation. L02/Pim-2 cells could generate hepatoma in athymic mice. In conclusion, Pim-2 could induce malignant transformation of human liver cell line L02.

Ren, Ke; Duan, Wentao; Shi, Yujun; Li, Bo; Liu, Zuojin

2010-01-01

214

Lack of Decorin Expression by Human Bladder Cancer Cells Offers New Tools in the Therapy of Urothelial Malignancies  

PubMed Central

Decorin, a multifunctional small leucine-rich extracellular matrix proteoglycan, has been shown to possess potent antitumour activity. However, there is some uncertainty whether different cancer cells express decorin in addition to non-malignant stromal cells. In this study we clarified decorin expression by human bladder cancer cells both in vivo and in vitro. In addition, the effect of adenovirus-mediated decorin expression on human bladder cancer cells in vitro was examined. We first demonstrated using the publicly available GeneSapiens databank that decorin gene expression is present in both normal and malignant human bladder tissues. However, when we applied in situ hybridization with digoxigenin-labeled RNA probes for decorin on human bladder carcinoma tissue samples derived from a large radical cystectomy patient cohort (n?=?199), we unambiguously demonstrated that invasive and non-invasive bladder carcinoma cells completely lack decorin mRNA. The cancer cells were also negative for decorin immunoreactivity. Instead, decorin expression was localized solely to original non-malignant stromal areas of bladder tissue. In accordance with the aforementioned results, human bladder cancer cells in vitro were also negative for decorin expression as shown by RT-qPCR analyses. The lack of decorin expression by bladder cancer cells was shown not to be due to the methylation of the proximal promoter region of the decorin gene. When bladder cancer cells were transfected with a decorin adenoviral vector, their proliferation was significantly decreased. In conclusion, we have shown that human bladder cancer cells are totally devoid of decorin expression. We have also shown that adenovirus-mediated decorin gene transduction of human bladder cancer cell lines markedly inhibits their proliferation. Thus, decorin gene delivery offers new potential therapeutic tools in urothelial malignancies.

Lund, Riikka; Vuorikoski, Sanna; Bostrom, Pia; Laato, Matti; Bostrom, Peter J.; Jarvelainen, Hannu

2013-01-01

215

Investigation of Radiosensitivity Gene Signatures in Cancer Cell Lines  

PubMed Central

Intrinsic radiosensitivity is an important factor underlying radiotherapy response, but there is no method for its routine assessment in human tumours. Gene signatures are currently being derived and some were previously generated by expression profiling the NCI-60 cell line panel. It was hypothesised that focusing on more homogeneous tumour types would be a better approach. Two cell line cohorts were used derived from cervix [n?=?16] and head and neck [n?=?11] cancers. Radiosensitivity was measured as surviving fraction following irradiation with 2 Gy (SF2) by clonogenic assay. Differential gene expression between radiosensitive and radioresistant cell lines (SF2 median) was investigated using Affymetrix GeneChip Exon 1.0ST (cervix) or U133A Plus2 (head and neck) arrays. There were differences within cell line cohorts relating to tissue of origin reflected by expression of the stratified epithelial marker p63. Of 138 genes identified as being associated with SF2, only 2 (1.4%) were congruent between the cervix and head and neck carcinoma cell lines (MGST1 and TFPI), and these did not partition the published NCI-60 cell lines based on SF2. There was variable success in applying three published radiosensitivity signatures to our cohorts. One gene signature, originally trained on the NCI-60 cell lines, did partially separate sensitive and resistant cell lines in all three cell line datasets. The findings do not confirm our hypothesis but suggest that a common transcriptional signature can reflect the radiosensitivity of tumours of heterogeneous origins.

Hall, John S.; Iype, Rohan; Senra, Joana; Taylor, Janet; Armenoult, Lucile; Oguejiofor, Kenneth; Li, Yaoyong; Stratford, Ian; Stern, Peter L.; O'Connor, Mark J.; Miller, Crispin J.; West, Catharine M. L.

2014-01-01

216

Renal allograft recipients with high susceptibility to cutaneous malignancy have an increased prevalence of human papillomavirus DNA in skin tumours and a greater risk of anogenital malignancy.  

PubMed Central

Renal allograft recipients (RARs) have a well-documented increased incidence of viral warts and cutaneous neoplasia, particularly those with long graft life and high sun exposure. A clinicopathological survey of 69 RARs in south-east Scotland, with follow-up periods of up to 28 years after transplantation, revealed marked variation in patient susceptibility to cutaneous malignancy with concomitant variation in HPV prevalence. Skin cancers were found in 34 patients. Eight patients showed high susceptibility [defined as more than four intraepidermal carcinomas (IECs) or invasive squamous cell carcinomas (SCCs)] 42 had intermediate susceptibility (1-3 IECs or SCCs, or >3 keratoses) and 18 had low susceptibility (< or = 3 keratoses and no cancers). SCCs, IECs and keratoses from the high-susceptibility group were found to have greater prevalences of human papillomavirus (HPV) DNA (56%, 45% and 50% respectively), than SCCs (0%) and IECs (33%) from intermediate-susceptibility RARs and keratoses (36%) from the combined intermediate- and low-susceptibility groups and compared with a group of immunocompetent controls (27%, 20% and 15% respectively). No differences in p53 protein accumulation, determined immunohistochemically, were observed in tumours from the three groups. Categorization of RARs by susceptibility to cutaneous malignancy provides clinically useful information, as significantly more high-susceptibility patients (38%) developed aggressive, potentially lethal anogenital or cutaneous squamous cell cancers than did patients in the intermediate group (5%, P=0.005) or the low-susceptibility group (0%).

Arends, M. J.; Benton, E. C.; McLaren, K. M.; Stark, L. A.; Hunter, J. A.; Bird, C. C.

1997-01-01

217

The prevalence of opportunistic infections and malignancies in autopsied patients with human immunodeficiency virus infection in Japan  

PubMed Central

Background Opportunistic infections and malignancies such as malignant lymphoma and Kaposi sarcoma are significant complications of human immunodeficiency virus (HIV) infection. However, following the introduction of antiretroviral therapy in Japan in 1997, the incidence of clinical complications has decreased. In the present study, autopsy cases of HIV infection in Japan were retrospectively investigated to reveal the prevalence of opportunistic infections and malignancies. Methods A total of 225 autopsy cases of HIV infection identified at 4 Japanese hospitals from 1985–2012 were retrospectively reviewed. Clinical data were collected from patient medical records. Results Mean CD4 counts of patients were 77.0 cells/?L in patients who received any antiretroviral therapy during their lives (ART (+) patients) and 39.6 cells/?L in naïve patients (ART (?) patients). Cytomegalovirus infection (142 cases, 63.1%) and pneumocystis pneumonia (66 cases, 29.3%) were the most frequent opportunistic infections, and their prevalence was significantly lower in ART (+) patients than ART (?) patients. Non-Hodgkin lymphoma and Kaposi sarcoma were observed in 30.1% and 16.2% of ART (?) patients, and 37.9% and 15.2% of ART (+) patients, respectively. Malignant lymphoma was the most frequent cause of death, followed by cytomegalovirus infection regardless of ART. Non-acquired immunodeficiency syndrome (AIDS)-defining cancers such as liver and lung cancer caused death more frequently in ART (+) patients (9.1%) than in ART (?) patients (1.5%; P?=?0.026). Conclusions The prevalence of infectious diseases and malignancies were revealed in autopsy cases of HIV infection in Japan. The prevalence of cytomegalovirus infection and pneumocystis pneumonia at autopsy were lower in ART (+) patients than ART (?) patients. Higher prevalence of non-AIDS defining malignancies among ART (+) patients than ART (?) patients suggests that onsets of various opportunistic infections and malignancies should be carefully monitored regardless of whether the patient is receiving ART.

2014-01-01

218

Analyse Biochimique des Facteurs Determinant la Croissance de Tumeurs Cancereuses Humaines en Culture D'Organes in Vitro (Biochemical Analysis of Factors Determining the Growth of Human Malignant Tumors in Organ Culture in Vitro).  

National Technical Information Service (NTIS)

The article presents a general view of biochemical analysis of factors determining organotypic growth of human malignant tumours in vitro. Two human malignant tumours of intestinal origin have been maintained for several years, and these tumours prolifera...

Y. Croisille J. Mason E. Wolff E. Wolff

1967-01-01

219

Pediatric Malignancies: Synopsis of Current Imaging Techniques  

Microsoft Academic Search

The imaging evaluation of malignancies is directed towards the assessment of size, location and characterization of the neoplasm.\\u000a Imaging children necessitates additional attention to the dose of radiation, given the radiosensitivity and the expected longevity\\u000a of children. This chapter will present some of the latest technologies used to image pediatric malignancies, as well as methods\\u000a to evaluate the most common

Sabah Servaes; Monica Epelman; Avrum Pollock; Karuna Shekdar

220

Radiosensitivity of lymphocytes among Filipinos: final report.  

National Technical Information Service (NTIS)

This report is about the studies on the radiosensitivity of Filipino lymphocytes to radiation that can elucidate on the potential of blood chromosomes as biological dosimeters. The objective of this study is to determine the radiosensitivity of lymphocyte...

F. I. S. Medina J. S. Gregorio C. P. Aguilar E. E. Poblete

1996-01-01

221

ZAP-70 is expressed by normal and malignant human B-cell subsets of different maturational stage.  

PubMed

ZAP-70 tyrosine kinase is involved in signalling pathways following T-cell receptor stimulation and was originally described only in T cells and natural killer cells. ZAP-70 expression has been reported in normal mouse B lineage cells and in human malignant B lymphocytes, mainly in chronic lymphocytic leukemia (CLL) where it correlates with clinical outcome. We analyzed several B-cell lines and ex vivo malignant B cells, ranging from acute lymphoblastic leukemia to multiple myeloma and reflecting different stages of B-cell differentiation, and they showed ZAP-70 expression regardless their maturation stage. We then analyzed by Western blot and flow cytometry different human normal B-lymphocyte subpopulations: naïve, germinal center and memory B cells from tonsils, CD19+ CD5+ cells from cord blood and CD19+ lymphocytes from peripheral blood. All expressed ZAP-70 protein, though at different levels depending on their differentiation, activation and tissue localization. In addition, ZAP-70 expression levels could be modulated following stimulation via the B-cell receptor. These findings implicate a potential role of ZAP-70 in the signalling pathway of B lymphocytes at different maturational stages, indicate that ZAP-70 expression is not a CLL-specific feature among B-cell malignancies and suggest that the absence of ZAP-70 rather than its presence should be considered abnormal for malignant B lymphocytes. PMID:16482211

Scielzo, C; Camporeale, A; Geuna, M; Alessio, M; Poggi, A; Zocchi, M R; Chilosi, M; Caligaris-Cappio, F; Ghia, P

2006-04-01

222

RHBDL2 Is a Critical Membrane Protease for Anoikis Resistance in Human Malignant Epithelial Cells  

PubMed Central

Anoikis resistance allows metastatic tumor cells to survive in a homeless environment. Activation of epithelial growth factor receptor (EGFR) signaling is one of the key mechanisms for metastatic tumor cells to resist anoikis, yet the regulation mechanisms of homeless-triggered EGFR activation in metastatic tumor cells remain unclear. Rhomboid-like-2 (RHBDL2), an evolutionally conserved intramembrane serine protease, can cleave the EGF ligand and thus trigger EGFR activation. Herein, we demonstrated that RHBDL2 overexpression in human epithelial cells resulted in promotion of cell proliferation, reduction of cell adhesion, and suppression of anoikis. During long-term suspension cultures, increased RHBDL2 was only detected in aggressive tumor cell lines. Treatment with the rhomboid protease inhibitor or RHBDL2 shRNA increased cleaved caspase 3, a marker of apoptosis. Finally, inhibition of EGFR activation increased the cleaved caspase 3 and attenuated the detachment-induced focal adhesion kinase phosphorylation. Taken together, these findings provide evidence for the first time that RHBDL2 is a critical molecule in anoikis resistance of malignant epithelial cells, possibly through the EGFR-mediated signaling. Our study demonstrates RHBDL2 as a new therapeutic target for cancer metastasis.

Lai, Chao-Han; Jiang, Shinn-Jong; Hung, Jui-Hsiang; Chang, Bi-Ing; Shi, Guey-Yueh; Wu, Hua-Lin

2014-01-01

223

Natural human interferon-beta in metastatic malignant melanoma. A phase II study.  

PubMed

A phase II trial of natural human fibroblast interferon (HuIFN-beta) in 15 previously untreated patients with advanced metastatic malignant melanoma is reported. It was given as out-patient treatment by 30 min i.v. infusion of 60 x 10(6) U/m2/day on 4 consecutive days each week. Systemic toxicity was acceptable to all patients except one who declined further treatment. Performance status of treated patients was good. Three patients had a partial response and 3 patients had stable disease. The median time to response was 13.3 weeks and the duration of response was 22.6 weeks. Responses were seen in lungs and soft tissues only and relapses were seen particularly in the central nervous system and the liver. Overall survival of the patients was only 20.7 weeks. Those who achieved a partial remission had a median survival of 34.7 weeks and those with disease stabilisation a survival of 22.0 weeks. HuIFN-beta is shown to have anti-tumour activity in advanced metastatic melanoma, although the unit dose of HuIFN-beta is much larger than that required to achieve similar anti-tumour activity with interferon-alpha. PMID:3233168

Abdi, E A; Tan, Y H; McPherson, T A

1988-01-01

224

Immunophenotype of human ovarian malignancies (cystadenocarcinomata and mixed müllerian tumor) established in SCID mice.  

PubMed

Human ovarian malignancies from three different patients (histology: two serous cystadenocarcinomata and one mixed Müllerian tumor, homologous type) were successfully serially transplanted intraperitoneally into severe combined immunodeficient (SCID) mice where the tumor cells spread around the peritoneal cavity. If the ascites derived from cystadenocarcinoma cells engrafted in the female genital tract of the SCID mice, they formed cystic tumors resembling remarkably well the original tumors in the patients. Immunohistochemical analysis revealed that the immunophenotype of the patients' original tumor and those grown in SCID mice were similar in the case of the two cystadenocarcinomata; in addition, the marker expression in general was stable during serial transplantation. If distant metastases occurred in the lungs, they immunophenotypically resembled those grown intraperitoneally. In contrast, the cells derived from the mixed Müllerian tumor shifted during serial transplantation from a spindle cell morphology toward a morphology characterized by cuboidal cells. The transition toward a more epithelial phenotype was accompanied by a changed immunophenotype of the tumor cells which became positive for epithelial cell markers such as carcinoembryonic antigens, CA 19-9 and CA 125. Concurrently with this differentiation, the p53 immunophenotype changed from positive to negative, indicating a further mutation in the p53 gene during serial passages. PMID:9316588

Schumacher, U; Adam, E; Dietl, J; Horny, H P

1997-04-01

225

Activation of the IGF-IR system contributes to malignant growth of human and mouse medulloblastomas.  

PubMed

Insulin-like growth factor I receptor (IGF-IR) has been implicated in the normal and malignant growth of many cell types including cells from the central nervous system. In the cerebellar cortex IGF-IR mRNA is found in granular cells and IGF-I stimulation is mitogenic and protects cells from low-potassium-induced apoptosis. Since primitive neuroectodermal tumors/medulloblastomas (PNETs/medulloblastomas) are suspected to originate from the external cerebellar granular layer, it is reasonable to postulate that IGF-IR and/or its signaling molecules may contribute to the transformation of these poorly differentiated cells. To study activation of the IGF-IR system in medulloblastomas, we have utilized an antibody (anti-pY1316) that specifically recognizes the phosphorylated (active) form of the IGF-IR. Medulloblastoma biopsy specimens were positive when examined immunohistochemically with anti-Y1316 antibody. Further analysis of the IGF-IR system was performed in three human (Daoy, TE-671, D283 Med) and four mouse (BsB8, BsB13, Bs-1b, Bs-1c) medulloblastoma cell lines. All the murine cell lines examined express IGF-IR and PI3-kinase at relatively normal levels, and grossly overexpress IRS-1, when compared with normal mouse cerebellum. Within 15 min following IGF-I stimulation both mouse and human cell lines phosphorylate the beta subunit of the IGF-IR, IRS-1, Akt, and MAP kinases. They respond with cell proliferation when stimulated solely with IGF-I and are strongly inhibited when challenged with a dominant negative mutant of the IGF-IR (486/STOP), or with antisense oligonucleotides against the IGF-IR mRNA. PMID:11439349

Wang, J Y; Del Valle, L; Gordon, J; Rubini, M; Romano, G; Croul, S; Peruzzi, F; Khalili, K; Reiss, K

2001-06-28

226

Mutational Analysis of Hedgehog Signaling Pathway Genes in Human Malignant Mesothelioma  

PubMed Central

Background The Hedgehog (HH) signaling pathway is critical for embryonic development and adult homeostasis. Recent studies have identified regulatory roles for this pathway in certain cancers with mutations in the HH pathway genes. The extent to which mutations of the HH pathway genes are involved in the pathogenesis of malignant mesothelioma (MMe) is unknown. Methodology/Principal Findings Real-time PCR analysis of HH pathway genes PTCH1, GLI1 and GLI2 were performed on 7 human MMe cell lines. Exon sequencing of 13 HH pathway genes was also performed in cell lines and human MMe tumors. In silico programs were used to predict the likelihood that an amino-acid substitution would have a functional effect. GLI1, GLI2 and PTCH1 were highly expressed in MMe cells, indicative of active HH signaling. PTCH1, SMO and SUFU mutations were found in 2 of 11 MMe cell lines examined. A non-synonymous missense SUFU mutation (p.T411M) was identified in LO68 cells. In silico characterization of the SUFU mutant suggested that the p.T411M mutation might alter protein function. However, we were unable to demonstrate any functional effect of this mutation on Gli activity. Deletion of exons of the PTCH1 gene was found in JU77 cells, resulting in loss of one of two extracellular loops implicated in HH ligand binding and the intracellular C-terminal domain. A 3-bp insertion (69_70insCTG) in SMO, predicting an additional leucine residue in the signal peptide segment of SMO protein was also identified in LO68 cells and a MMe tumour. Conclusions/Significance We identified the first novel mutations in PTCH1, SUFU and SMO associated with MMe. Although HH pathway mutations are relatively rare in MMe, these data suggest a possible role for dysfunctional HH pathway in the pathogenesis of a subgroup of MMe and help rationalize the exploration of HH pathway inhibitors for MMe therapy.

Lim, Chuan Bian; Prele, Cecilia M.; Cheah, Hui Min; Cheng, Yuen Yee; Klebe, Sonja; Reid, Glen; Watkins, D. Neil; Baltic, Svetlana; Thompson, Philip J.; Mutsaers, Steven E.

2013-01-01

227

Extract of Cordyceps militaris inhibits angiogenesis and suppresses tumor growth of human malignant melanoma cells.  

PubMed

Angiogenesis is essential for tumor development and metastasis. Among several angiogenic factors, vascular endothelial growth factor receptor (VEGF) is important for tumor-derived angiogenesis and commonly overexpressed in solid tumors. Thus, many antitumor strategies targeting VEGF have been developed to inhibit cancer angiogenesis, offering insights into the successful treatment of solid cancers. However, there are a number of issues such as harmful effects on normal vascularity in clinical trials. Taking this into consideration, we employed Cordyceps militaris as an antitumor approach due to its biological safety in vivo. The herbal medicinal mushroom Cordyceps militaris has been reported to show potential anticancer properties including anti-angiogenic capacity; however, its concrete properties have yet to be fully demonstrated. In this study, we aimed to elucidate the biological role of Cordyceps militaris extract in tumor cells, especially in regulating angiogenesis and tumor growth of a human malignant melanoma cell line. We demonstrated that Cordyceps militaris extract remarkably suppressed tumor growth via induction of apoptotic cell death in culture that links to the abrogation of VEGF production in melanoma cells. This was followed by mitigation of Akt1 and GSK-3? activation, while p38? phosphorylation levels were increased. Extract treatment in mouse model xenografted with human melanoma cells resulted in a dramatic antitumor effect with down-regulation of VEGF expression. The results suggest that suppression of tumor growth by Cordyceps militaris extract is, at least, mediated by its anti-angiogenicity and apoptosis induction capacities. Cordyceps militaris extract may be a potent antitumor herbal drug for solid tumors. PMID:24789042

Ruma, I Made Winarsa; Putranto, Endy Widya; Kondo, Eisaku; Watanabe, Risayo; Saito, Ken; Inoue, Yusuke; Yamamoto, Ken-Ichi; Nakata, Susumu; Kaihata, Masaji; Murata, Hitoshi; Sakaguchi, Masakiyo

2014-07-01

228

Radioimmunoassay for human pancreatic ribonuclease and measurement of serum immunoreactive pancreatic ribonuclease in patients with malignant tumors  

SciTech Connect

A method for radioimmunoassay of human pancreatic RNase was developed. The method is sensitive, reproducible, and specific. Almost no cross-reactivity exists between human pancreatic and liver RNases. A good correlation was observed between the serum concentration of pancreatic RNase as measured by radioimmunoassay and its enzymatic activity using polycytidylic acid as substrate. The concentration of serum pancreatic RNase correlates well with age, blood urea nitrogen, and albumin contents but does not correlate with serum amylase activity. Using the data of 52 patients with malignant tumors except pancreatic cancer, serum RNase level could be expressed by a multiple regression equation: Immunoreactive RNase content in pancreatic cancer was elevated in patients with complications from renal failure. Serum pancreatic RNase contents in patients with pancreatic cancer measured by radioimmunoassay agreed well with the values calculated using the equation derived from the data of patients with other malignant tumors.

Kurihara, M.; Ogawa, M.; Ohta, T.; Kurokawa, E.; Kitahara, T.; Murata, A.; Matsuda, K.; Kosaki, G.; Watanabe, T.; Wada, H.

1984-05-01

229

Determination of hyperglycosylated human chorionic gonadotropin produced by malignant gestational trophoblastic neoplasias and male germ cell tumors using a lectin-based immunoassay and surface plasmon resonance  

Microsoft Academic Search

The ability to reliably detect aberrant glycosylation of human chorionic gonadotropin (hCG) may have profound implications for the diagnosis and monitoring of malignant gestational trophoblastic neoplasia, germ cell tumors, other malignancies, and pregnancy complications. To become a clinically useful assay, however, this discrimination of glycoforms should be possible on minimally treated biological specimens. Towards this end, we have developed a

Lisa S. Kelly; Steven Birken; David Puett

2007-01-01

230

The radiosensitizing potential of glutaraldehyde on MCF7 breast cancer cells as quantified by means of the G2-chromosomal radiosensitivity assay.  

PubMed

Glutaraldehyde (GA) is a high production volume chemical that is very reactive with a wide spectrum of medical, scientific and industrial applications. Concerning the genotoxic and carcinogenic effect of GA, controversial results have been reported, while in humans no studies with positive carcinogenic results for GA have been published. However, our previous study concerning the combined effects of exposure to both GA and ionising radiation (IR) in peripheral blood lymphocytes of healthy donors has shown that non-genotoxic doses of the chemical induces a statistically significant increase in chromosomal radiosensitivity. The lack of information concerning the radiosensitizing potential of GA on cancerous cells triggered us to test the radiosensitizing effect of GA on breast cancer cells (MCF7). For this purpose the G2-chromosomal radiosensitivity assay (G2-assay) was used. The assay involves G2-phase irradiation and quantitation of the chromosomal fragility in the subsequent metaphase. The experimental data show that 48 h exposure to GA, at doses that are not clastogenic to MCF7 breast cancer cells enhances G2-chromosomal radiosensitivity of this cell line. In an effort to evaluate whether the observed increase in GAs-induced G2-chromosomal radiosensitization is linked to GA-induced alterations in the cell cycle and feedback control mechanism, Mitotic Index analysis was performed. The results have shown that such a mechanism cannot be directly related to the observed GA-induced increase in G2-chromosomal radiosensitivity. Since increased G2-chromosomal radiosensitivity has been linked with cancer proneness, the radiosensitizing effect of GA at non-clastogenic doses highlights its potential carcinogenic profile. PMID:21556769

Hatzi, Vasiliki I; Terzoudi, Georgia I; Barszczewska, Katarzyna; Makropoulos, Vasilios; Pantelias, Gabriel E

2012-01-01

231

The Scatter Factor\\/Hepatocyte Growth Factor: c-Met Pathway in Human Embryonal Central Nervous System Tumor Malignancy  

Microsoft Academic Search

Embryonal central nervous system (CNS) tumors, which comprise medulloblastoma, are the most common malignant brain tumors in children. The role of the growth factor scat- ter factor\\/hepatocyte growth factor (SF\\/HGF) and its tyro- sine kinase receptor c-Met in these tumors has been until now completely unknown. In the present study, we show that human embryonal CNS tumor cell lines and

Yunqing Li; Bachchu Lal; Sherwin Kwon; Xing Fan; Usha Saldanha; Thomas E. Reznik; Eric B. Kuchner; Charles Eberhart; John Laterra; Roger Abounader

2005-01-01

232

The status of microRNA21 expression and its clinical significance in human cutaneous malignant melanoma  

Microsoft Academic Search

Dysregulation of microRNA-21 plays critical roles in tumor initiation and progression. The purpose of this study was to investigate the status of microRNA-21 expression in human cutaneous malignant melanoma and determine its clinical significance. TaqMan® real-time RT-PCR assay was performed to examine the expression of microRNA-21 in 10 cases of dysplastic nevi, 86 cases of primary cutaneous melanomas, 10 cases

Li Jiang; Xiaoxing Lv; Jing Li; Jinqing Li; Xueyong Li; Wangzhou Li; Yuejun Li

233

DNA ploidy-characteristics of human malignant melanoma analysed by flow cytometry and compared with histology and clinical course  

Microsoft Academic Search

Summary  Flow cytometric analysis of nuclear DNA content is valuable for indicating ploidy- and proliferation abnormalities in surgically\\u000a removed human malignant melanomas. In 35 primary cutaneous melanomas, 20 metastases of melanoma in skin and lymph nodes, and\\u000a 16 nevi the DNA distribution was analyzed by flow cytometry and compared with a variety of histological parameters and the\\u000a subsequent clinical course.\\u000a \\u000a Heteroploid

Knud Søndergaard; Jørgen K. Larsen; Ulla Møller; Ib J. Christensen; Klaus Hou-Jensen

1982-01-01

234

The Guanine Nucleotide Exchange Factor SWAP-70 Modulates the Migration and Invasiveness of Human Malignant Glioma Cells12  

PubMed Central

The malignant glioma is the most common primary human brain tumor. Its tendency to invade away from the primary tumor mass is considered a leading cause of tumor recurrence and treatment failure. Accordingly, the molecular pathogenesis of glioma invasion is currently under investigation. Previously, we examined a gene expression array database comparing human gliomas to nonneoplastic controls and identified several Rac guanine nucleotide exchange factors with differential expression. Here, we report that the guanine nucleotide exchange factor SWAP-70 has increased expression in malignant gliomas and strongly correlates with lowered patient survival. SWAP-70 is a multifunctional signaling protein involved in membrane ruffling that works cooperatively with activated Rac. Using a glioma tissue microarray, we validated that SWAP-70 demonstrates higher expression in malignant gliomas compared with low-grade gliomas or nonneoplastic brain tissue. Through immunofluorescence, SWAP-70 localizes to membrane ruffles in response to the growth factor, epidermal growth factor. To assess the role of SWAP-70 in glioma migration and invasion, we inhibited its expression withsmall interfering RNAs and observed decreased glioma cell migration and invasion. SWAP-70 overexpression led to increased levels of active Rac even in low-serum conditions. In addition, when SWAP-70 was overexpressed in glioma cells, we observed enhanced membrane ruffle formation followed by increased cellmigration and invasiveness. Taken together, our findings suggest that the guanine nucleotide exchange factor SWAP-70 plays an important role in the migration and invasion of human gliomas into the surrounding tissue.

Seol, Ho Jun; Smith, Christian A; Salhia, Bodour; Rutka, James T

2009-01-01

235

The Methanol Extract of Angelica sinensis Induces Cell Apoptosis and Suppresses Tumor Growth in Human Malignant Brain Tumors.  

PubMed

Glioblastoma multiforme (GBM) is a highly vascularized and invasive neoplasm. The methanol extract of Angelica sinensis (AS-M) is commonly used in traditional Chinese medicine to treat several diseases, such as gastric mucosal damage, hepatic injury, menopausal symptoms, and chronic glomerulonephritis. AS-M also displays potency in suppressing the growth of malignant brain tumor cells. The growth suppression of malignant brain tumor cells by AS-M results from cell cycle arrest and apoptosis. AS-M upregulates expression of cyclin kinase inhibitors, including p16, to decrease the phosphorylation of Rb proteins, resulting in arrest at the G0-G1 phase. The expression of the p53 protein is increased by AS-M and correlates with activation of apoptosis-associated proteins. Therefore, the apoptosis of cancer cells induced by AS-M may be triggered through the p53 pathway. In in vivo studies, AS-M not only suppresses the growth of human malignant brain tumors but also significantly prolongs patient survival. In addition, AS-M has potent anticancer effects involving cell cycle arrest, apoptosis, and antiangiogenesis. The in vitro and in vivo anticancer effects of AS-M indicate that this extract warrants further investigation and potential development as a new antibrain tumor agent, providing new hope for the chemotherapy of malignant brain cancer. PMID:24319475

Lin, Yu-Ling; Lai, Wen-Lin; Harn, Horng-Jyh; Hung, Pei-Hsiu; Hsieh, Ming-Chang; Chang, Kai-Fu; Huang, Xiao-Fan; Liao, Kuang-Wen; Lee, Ming-Shih; Tsai, Nu-Man

2013-01-01

236

The Methanol Extract of Angelica sinensis Induces Cell Apoptosis and Suppresses Tumor Growth in Human Malignant Brain Tumors  

PubMed Central

Glioblastoma multiforme (GBM) is a highly vascularized and invasive neoplasm. The methanol extract of Angelica sinensis (AS-M) is commonly used in traditional Chinese medicine to treat several diseases, such as gastric mucosal damage, hepatic injury, menopausal symptoms, and chronic glomerulonephritis. AS-M also displays potency in suppressing the growth of malignant brain tumor cells. The growth suppression of malignant brain tumor cells by AS-M results from cell cycle arrest and apoptosis. AS-M upregulates expression of cyclin kinase inhibitors, including p16, to decrease the phosphorylation of Rb proteins, resulting in arrest at the G0-G1 phase. The expression of the p53 protein is increased by AS-M and correlates with activation of apoptosis-associated proteins. Therefore, the apoptosis of cancer cells induced by AS-M may be triggered through the p53 pathway. In in vivo studies, AS-M not only suppresses the growth of human malignant brain tumors but also significantly prolongs patient survival. In addition, AS-M has potent anticancer effects involving cell cycle arrest, apoptosis, and antiangiogenesis. The in vitro and in vivo anticancer effects of AS-M indicate that this extract warrants further investigation and potential development as a new antibrain tumor agent, providing new hope for the chemotherapy of malignant brain cancer.

Lai, Wen-Lin; Harn, Horng-jyh; Hung, Pei-Hsiu; Hsieh, Ming-Chang; Chang, Kai-Fu; Huang, Xiao-Fan; Liao, Kuang-Wen; Lee, Ming-Shih; Tsai, Nu-Man

2013-01-01

237

Emergence of fractal behavior and other changes of cell surface during malignant transformation: AFM study of human cervical epithelial cells  

NASA Astrophysics Data System (ADS)

Fractal behavior, self-similarity when zooming in or out, is frequently found in natural patterns emerged from chaos or any far from equilibrium systems. While expected and observed for tissues, the emergence of fractal behavior associated with malignant transformations was not observed at the level of single cell. Here report on the appearance of fractal behavior when normal human cervical epithelial cells become malignant. This was found by analyzing the adhesion maps imaged with AFM working in HarmoniX mode. Normal and malignant (a mix of cancerous and precancerous) cells were enzymatic only extracted from cervical tissue of healthy individuals and cancer patients, respectively. A surprising 100% discrimination of malignant and normal cells was observed. Although we previously reported differences in surface (brush) layer of cancer cells, the unambiguous quantitative divergence of the fractal behavior of the adhesion maps is a surprise (in particular, when compared to no difference found in the regular AFM images). The nature of the observed difference in the adhesion behavior will be discussed. These results may suggest that the fractal dimensionality can be treated as a new potential ``physicomarker'' for detection of individual cervical cancer cells.

Dokukin, Maxim; Guz, Nataliia; Woodworth, Craig; Sokolov, Igor

2012-02-01

238

In the absence of IGF-1 signaling, IFN-gamma suppresses human malignant T-cell growth.  

PubMed

Several approaches to target insulin-like growth factor-1 (IGF-1) signaling have resulted in the inhibition of the growth of a broad range of tumor cells. Malignant T cells are insensitive to the antiproliferative effects of the interferon-gamma (IFN-gamma)/signal transducer and activator of transcription 1 (STAT1) pathway because of the IGF-1-dependent internalization of the IFN-gammaR2 signaling chain. Here we show that human malignant T cells are also resistant to the growth inhibitory effect of both the IGF-1 receptor-specific inhibitor picropodophyllin (PPP) and retrovirus-mediated gene transfer of a dominant negative IGF-1 receptor. However, blockade of IGF-1 receptor perturbs IFN-gammaR2 internalization and induces its cell surface accumulation in malignant T cells. This allows the reinstatement of the IFN-gamma-induced STAT1 activation, a high expression of proapoptotic molecules, and the suppression of malignant T-cell growth both in vitro and in vivo in a severe combined immunodeficiency (SCID) mouse model. These data indicate that the inhibition of IGF-1 signaling combined with IFN-gamma administration could be a promising approach to suppress the growth of neoplastic T cells resistant to each treatment on its own. PMID:17148586

Conti, Laura; Regis, Gabriella; Longo, Angela; Bernabei, Paola; Chiarle, Roberto; Giovarelli, Mirella; Novelli, Francesco

2007-03-15

239

Altered expression of G/sub 1/-specific genes in human malignant myeloid cells  

SciTech Connect

The authors have studied the expression of cell-cycle genes specific to the G/sub 1/ (2A9, 2F1, 4F1, c-myc) and S (histone H3) phases of the cell cycle in normal and malignant human myeloid cycling cells. The levels of expression were determined by measuring the amounts of specific RNA in blot hybridization assays. Levels of expression of the G/sub 1/ genes were compared to the level of expression of the S-phase-specific H3 gene. In a normal asynchronous system provided by the bone marrow cells of three normal donors, the expressions of the four G/sub 1/-specific genes 2A9, 2F1, 4F1, and c-myc, and of the S-phase-specific gene H3 were in ratios that differed little from one individual to another. In the total RNA of eight patients in the chronic phase of chronic myelogenous leukemia, a high level of expression of G/sub 1/ cell-cycle genes was paralleled by a high level of expression of the S-phase H3 gene, simply reflecting and increase in the fraction of proliferating cells. In patients with acute myelogenous leukemia (AML), the RNA levels of 2F1 and 4F1 paralleled the expression of H3. However, in 9 of 10 patients with AML they found that the expression of c-myc was elevated with respect to H3 expression. Two important conclusions can be drawn from these findings: (i) increased levels of a G/sub 1/-specific RNA in a tumor may not indicate overexpression of that gene but may instead simply reflect the fraction of proliferating cells; and (ii) in some patients with AML, however, the expression of certain G/sub 1/ genes is truly deregulated and might contribute to the impairment of proliferative control that is associated with this phenotype.

Calabretta, B.; Venturelli, D.; Kaczmarek, L.; Narni, F.; Talpaz, M.; Anderson, B.; Beran, M.; Baserga, R.

1986-03-01

240

Fine mapping of V(D)J recombinase mediated rearrangements in human lymphoid malignancies  

PubMed Central

Background Lymphocytes achieve diversity in antigen recognition in part by rearranging genomic DNA at loci encoding antibodies and cell surface receptors. The process, termed V(D)J recombination, juxtaposes modular coding sequences for antigen binding. Erroneous recombination events causing chromosomal translocations are recognized causes of lymphoid malignancies. Here we show a hybridization based method for sequence enrichment can be used to efficiently and selectively capture genomic DNA adjacent to V(D)J recombination breakpoints for massively parallel sequencing. The approach obviates the need for PCR amplification of recombined sequences. Results Using tailored informatics analyses to resolve alignment and assembly issues in these repetitive regions, we were able to detect numerous recombination events across a panel of cancer cell lines and primary lymphoid tumors, and an EBV transformed lymphoblast line. With reassembly, breakpoints could be defined to single base pair resolution. The observed events consist of canonical V(D)J or V-J rearrangements, non-canonical rearrangements, and putatively oncogenic reciprocal chromosome translocations. We validated non-canonical and chromosome translocation junctions by PCR and Sanger sequencing. The translocations involved the MYC and BCL-2 loci, and activation of these was consistent with histopathologic features of the respective B-cell tumors. We also show an impressive prevalence of novel erroneous V-V recombination events at sites not incorporated with other downstream coding segments. Conclusions Our results demonstrate the ability of next generation sequencing to describe human V(D)J recombinase activity and provide a scalable means to chronicle off-target, unexpressed, and non-amplifiable recombinations occurring in the development of lymphoid cancers.

2013-01-01

241

Role for Calcium-Activated Potassium Channels (BK) in Growth Control of Human Malignant Glioma Cells  

PubMed Central

Voltage-dependent large-conductance Ca2+-activated K+ channels, often referred to as BK channels, are a unique class of ion channels coupling intracellular chemical signaling to electrical signaling. BK channel expression has been shown to be up-regulated in human glioma biopsies, and expression levels correlate positively with the malignancy grade of the tumor. Glioma BK channels (gBK) are a splice variant of the hslo gene, are characterized by enhanced sensitivity to [Ca2+]i, and are the target of modulation by growth factors. By using the selective pharmacological BK channel inhibitor iberiotoxin, we examined the potential role of these channels in tumor growth. Cell survival assays examined the ability of glioma cells to grow in nominally serum-free medium. Under such conditions, BK channel inhibition by iberiotoxin caused a dose- and time-dependent decrease in cell number discernible as early as 72 hr after exposure and maximal growth inhibition after 4-5 days. FACS analysis shows that IbTX treatment arrests glioma cells in S phase of the cell cycle, whereupon cells undergo cell death. Interestingly, IbTX effects were nullified when cells were maintained in 7% fetal calf serum. Electrophysiological analysis, in conjunction with biotinylation studies, demonstrates that serum starvation caused a significant translocation of BK channel protein to the plasma membrane, corresponding to a two- to threefold increase in whole-cell conductance, but without a change in total gBK protein. Hence, expression of functional gBK channels appears to be regulated in a growth-factor-dependent manner, with enhanced surface expression promoting tumor cell growth under conditions of growth factor deprivation as might occur under in vivo conditions.

Weaver, Amy K.; Liu, Xiaojin; Sontheimer, Harald

2008-01-01

242

Treatment of Human Malignant Meningiomas by G207, a Replication-competent Mu11 ¡mutated Herpes Simplex Virus I1  

Microsoft Academic Search

We have demonstrated that replication-competent attenuated mutants of herpes simplex virus type 1 ilISV-l i have therapeutic potential for malignant gliomas. Moreover, a recently described multiple mutant HSV (termed C207) has properties which may allow human clinical trials. G207 is able to replicate within and kill cells from three human malignant meningiomas in cell culture. In nude mice harboring s.c.

Takahito Yazaki; Herbert J. Manz; Samuel D. Rabkin; Robert L. Martuza

243

The activation of human endogenous retrovirus K (HERV-K) is implicated in melanoma cell malignant transformation.  

PubMed

Melanoma development is a multi-step process arising from a series of genetic and epigenetic events. Although the sequential stages involved in progression from melanocytes to malignant melanoma are clearly defined, our current understanding of the mechanisms leading to melanoma onset is still incomplete. Growing evidence show that the activation of endogenous retroviral sequences might be involved in transformation of melanocytes as well as in the increased ability of melanoma cells to escape immune surveillance. Here we show that human melanoma cells in vitro undergo a transition from adherent to a more malignant, non-adherent phenotype when exposed to stress conditions. Melanoma-derived non-adherent cells are characterized by an increased proliferative potential and a decreased expression of both HLA class I molecules and Melan-A/MART-1 antigen, similarly to highly malignant cells. These phenotypic and functional modifications are accompanied by the activation of human endogenous retrovirus K expression (HERV-K) and massive production of viral-like particles. Down-regulation of HERV-K expression by RNA interference prevents the transition from the adherent to the non-adherent growth phenotype in low serum. These results implicate HERV-K in at least some critical steps of melanoma progression. PMID:19167380

Serafino, A; Balestrieri, E; Pierimarchi, P; Matteucci, C; Moroni, G; Oricchio, E; Rasi, G; Mastino, A; Spadafora, C; Garaci, E; Vallebona, P Sinibaldi

2009-03-10

244

The activation of human endogenous retrovirus K (HERV-K) is implicated in melanoma cell malignant transformation  

SciTech Connect

Melanoma development is a multi-step process arising from a series of genetic and epigenetic events. Although the sequential stages involved in progression from melanocytes to malignant melanoma are clearly defined, our current understanding of the mechanisms leading to melanoma onset is still incomplete. Growing evidence show that the activation of endogenous retroviral sequences might be involved in transformation of melanocytes as well as in the increased ability of melanoma cells to escape immune surveillance. Here we show that human melanoma cells in vitro undergo a transition from adherent to a more malignant, non-adherent phenotype when exposed to stress conditions. Melanoma-derived non-adherent cells are characterized by an increased proliferative potential and a decreased expression of both HLA class I molecules and Melan-A/MART-1 antigen, similarly to highly malignant cells. These phenotypic and functional modifications are accompanied by the activation of human endogenous retrovirus K expression (HERV-K) and massive production of viral-like particles. Down-regulation of HERV-K expression by RNA interference prevents the transition from the adherent to the non-adherent growth phenotype in low serum. These results implicate HERV-K in at least some critical steps of melanoma progression.

Serafino, A. [Institute of Neurobiology and Molecular Medicine - ARTOV, CNR via Fosso del Cavaliere 100, 00133 - Rome (Italy)], E-mail: annalucia.serafino@artov.inmm.cnr.it; Balestrieri, E. [Department of Experimental Medicine and Biochemical Science - University of Rome 'Tor Vergata', via Montpellier, 00133 - Rome (Italy); Pierimarchi, P. [Institute of Neurobiology and Molecular Medicine - ARTOV, CNR via Fosso del Cavaliere 100, 00133 - Rome (Italy); Matteucci, C.; Moroni, G. [Department of Experimental Medicine and Biochemical Science - University of Rome 'Tor Vergata', via Montpellier, 00133 - Rome (Italy); Oricchio, E. [Department of Experimental Medicine and Biochemical Science - University of Rome 'Tor Vergata', via Montpellier, 00133 - Rome (Italy); Istituto Superiore di Sanita, Viale Regina Elena, 299, 00161 - Rome (Italy); Rasi, G. [Institute of Neurobiology and Molecular Medicine - ARTOV, CNR via Fosso del Cavaliere 100, 00133 - Rome (Italy); Mastino, A. [Department of Life Sciences, University of Messina, Salita Sperone 31, 98166 - Messina (Italy); Spadafora, C. [Istituto Superiore di Sanita, Viale Regina Elena, 299, 00161 - Rome (Italy); Garaci, E.; Vallebona, P. Sinibaldi [Department of Experimental Medicine and Biochemical Science - University of Rome 'Tor Vergata', via Montpellier, 00133 - Rome (Italy)

2009-03-10

245

Etiologic Studies of Radiosensitive Tumors  

Cancer.gov

Ionizing radiation is perhaps the most clearly understood of all carcinogens. However, tumors known to be radiosensitive also have other possible causal or modifying factors. This page describes DCEG research into the general etiology of a number of specific radiation-related cancers.

246

A prospective study comparing human metapneumovirus with other respiratory viruses in adults with hematologic malignancies and respiratory tract infections.  

PubMed

Human metapneumovirus (hMPV) is a recently described paramyxovirus associated with upper and lower respiratory-tract infection (URI and LRI, respectively). We conducted a prospective study of URI and LRI in adults with hematologic malignancies during a 4-year period. We retrospectively tested samples by reverse-transcription polymerase chain reaction for hMPV and analyzed clinical data. Twenty-two (9%) of 251 episodes of respiratory infection tested positive for hMPV. Sixteen (73%) of the illnesses occurred in hematopoietic stem-cell transplant recipients. Nine patients with hMPV developed LRI; 3 of these patients died. hMPV is a common cause of respiratory infections in adults with hematologic malignancies, with associated morbidity and mortality. PMID:16107960

Williams, John V; Martino, Rodrigo; Rabella, Núria; Otegui, Magdalena; Parody, Rocio; Heck, Joshua M; Crowe, James E

2005-09-15

247

ALDH1 is a marker of normal and malignant human mammary stem cells and a predictor of poor clinical outcome  

PubMed Central

Application of stem cell biology to breast cancer research has been limited by the lack of simple methods for identification and isolation of normal and malignant stem cells. Utilizing in vitro and in vivo experimental systems, we show that normal and cancer human mammary epithelial cells with increased aldehyde dehydrogenase activity (ALDH) have stem/progenitor properties. These cells contain the subpopulation of normal breast epithelium with the broadest lineage differentiation potential and greatest growth capacity in a xenotransplant model. In breast carcinomas, high ALDH activity identifies the tumorigenic cell fraction, capable of self-renewal and of generating tumors which recapitulate the heterogeneity of the parental tumor. In a series of 577 breast carcinomas, expression of ALDH1 detected by immunostaining correlated with poor prognosis. These findings offer an important new tool for the study of normal and malignant breast stem cells and facilitate the clinical application of stem cell concepts.

Ginestier, Christophe; Hur, Min Hee; Charafe-Jauffret, Emmanuelle; Monville, Florence; Dutcher, Julie; Brown, Marty; Jacquemier, Jocelyne; Viens, Patrice; Kleer, Celina; Liu, Suling; Schott, Anne; Hayes, Dan; Birnbaum, Daniel; Wicha, Max S.; Dontu, Gabriela

2008-01-01

248

Analysis of the expression profile of Dickkopf-1 gene in human glioma and the association with tumor malignancy  

PubMed Central

Background Gliomas represent the most common primary malignant brain tumors, yet little is known about the molecular pathogenesis of these tumors. The highly-regulated Wnt signal transduction pathway is essential for normal developmental processes, and defects in the pathway are closely linked to oncogenesis. Dickkopf-1 (DKK-1) is a secreted protein that acts as a potent inhibitor of the Wnt pathway. The aim of this study was to examine the expression profile of DKK-1 gene in human glioma and its association with tumor malignancy. Methods We determined the expression levels of DKK-1 transcript and protein in 12 glioblastoma cell lines, medulloblastoma cells, low-grade glioma cells, and human astrocyte cells by semiquantitative RT-PCR and ELISA. A total of 47 tumor biopsy specimens and 11 normal brain tissue samples from patients with cerebral trauma internal decompression were embedded in paraffin blocks and used for immunostaining. Twenty-six primary tumors and 7 corresponding brain samples were stored in liquid nitrogen and used for RT-PCR. We further examined serologic concentrations and cerebral fluid levels of DKK-1 in patients with tumors. Results DKK-1 could only be detected in 12 human glioblastoma cell lines, not in a panel of other tumor and normal cell lines. The difference between glioma patients and healthy individuals was significant. Kendall's tau-c association analysis also revealed the increased DKK-1 protein expression in tumor tissues of higher pathologic classification. The levels of cerebral fluid DKK-1 protein were significantly higher in glioma patients than in healthy donors or in neuronal benign tumor patients, suggesting that the DKK-1 molecule in cerebral fluids can be applicable to detect the presence of glioma and be developed as a novel prognostic treatment. Conclusion The Wnt antagonist DKK-1 gene may have important roles in glioma tumorigenesis and act as a novel biomarker in human malignant glioblastoma.

2010-01-01

249

TLR9-mediated siRNA delivery for targeting of normal and malignant human hematopoietic cells in vivo  

PubMed Central

STAT3 operates in both cancer cells and tumor-associated immune cells to promote cancer progression. As a transcription factor, it is a highly desirable but difficult target for pharmacologic inhibition. We have recently shown that the TLR9 agonists CpG oligonucleotides can be used for targeted siRNA delivery to mouse immune cells. In the present study, we demonstrate that a similar strategy allows for targeted gene silencing in both normal and malignant human TLR9+ hematopoietic cells in vivo. We have developed new human cell-specific CpG(A)-STAT3 siRNA conjugates capable of inducing TLR9-dependent gene silencing and activation of primary immune cells such as myeloid dendritic cells, plasmacytoid dendritic cells, and B cells in vitro. TLR9 is also expressed by several human hematologic malignancies, including B-cell lymphoma, multiple myeloma, and acute myeloid leukemia. We further demonstrate that oncogenic proteins such as STAT3 or BCL-XL are effectively knocked down by specific CpG(A)-siRNAs in TLR9+ hematologic tumor cells in vivo. Targeting survival signaling using CpG(A)-siRNAs inhibits the growth of several xenotransplanted multiple myeloma and acute myeloid leukemia tumors. CpG(A)-STAT3 siRNA is immunostimulatory and nontoxic for normal human leukocytes in vitro. The results of the present study show the potential of using tumoricidal/immunostimulatory CpG-siRNA oligonucleotides as a novel 2-pronged therapeutic strategy for hematologic malignancies.

Zhang, Qifang; Hossain, Dewan Md Sakib; Nechaev, Sergey; Kozlowska, Anna; Zhang, Wang; Liu, Yong; Kowolik, Claudia M.; Swiderski, Piotr; Rossi, John J.; Forman, Stephen; Pal, Sumanta; Bhatia, Ravi; Raubitschek, Andrew

2013-01-01

250

Similarities between human ataxia fibroblasts and murine SCID cells: high sensitivity to gamma rays and high frequency of methotrexate-induced DHFR gene amplification, but normal radiosensitivity to densely ionizing alpha particles.  

PubMed

Two gamma-ray hypersensitive cell lines, human ataxia telangiectasia (AT) and murine severe combined immune deficiency (SCID) cells, proved to be very competent in amplifying their dihydrofolate reductase (DHFR) gene under methotrexate selection stress. Over a period of months, methotrexate-resistant clones were obtained which were able to grow in progressively increasing methotrexate concentrations up to 1 mM. By then methotrexate-resistant AT and SCID cells had amplified their DHFR gene 6- and 30-fold, respectively, and showed very high DHFR mRNA expression. In contrast, related cells with normal radiosensitivity (human GM637 and mouse BALB/c fibroblasts) did not show DHFR gene amplification under comparable conditions. This correlation of the capacity of DHFR gene amplification and gamma-ray hypersensitivity in AT and SCID cells suggests that gene amplification may have a mechanism(s) in common with those involved in repair of gamma-radiation-induced damage. No difference in cell killing could be observed following exposure to densely ionizing alpha particles: AT and SCID cells exhibited comparable survival rates to GM637 and BALB/c cells, respectively. PMID:7809366

Lücke-Huhle, C

1994-01-01

251

Role of the common ? chain in cell cycle progression of human malignant cell lines.  

PubMed

The ?-chain (?c) is a transducing element shared between several cytokine receptors whose alteration causes X-linked severe combined immunodeficiency. Recently, a direct involvement of ?c in self-sufficient growth in a concentration-dependent manner was described, implying a direct relationship between the amount of the molecule and its role in cell cycle progression. In this study, we evaluate whether ?c expression could interfere in cell cycle progression also in malignant hematopoietic cells. Here, we first report that in the absence of ?c expression, lymphoblastoid B-cell lines (BCLs) die at a higher extent than control cells. This phenomenon is caspase-3 independent and is associated to a decreased expression of the antiapoptotic Bcl-2 family members. By contrast, increased expression of ?c protein directly correlates with spontaneous cell growth in several malignant hematopoietic cell lines. We, also, find that the knockdown of ?c protein through short interfering RNA is able to decrease the cell proliferation rate in these malignancies. Furthermore, an increased expression of all D-type cyclins is found in proliferating neoplastic cells. In addition, a direct correlation between the amount of ?c and cyclins A2 and B1 expression is found. Hence, our data demonstrate that the amount of the ?c is able to influence the transcription of genes involved in cell cycle progression, thus being directly involved in the regulatory control of cell proliferation of malignant hematopoietic cells. PMID:22223761

Vigliano, Ilaria; Palamaro, Loredana; Bianchino, Gabriella; Fusco, Anna; Vitiello, Laura; Grieco, Vitina; Romano, Rosa; Salvatore, Marco; Pignata, Claudio

2012-03-01

252

Farnesyltransferase Inhibitors and Human Malignant Pleural Mesothelioma: A First-Step Comparative Translational Study  

Microsoft Academic Search

It is known that the potential clinical use of farnesyl- transferase inhibitors (FTI) could be expanded to include cancers harboring activated receptor tyrosine kinases. Approximately 70% of malignant pleural mesotheliomas (MPM) overexpress epidermal growth factor receptors (EGFR) and a subset express both EGFR and transforming growth factor A (TGF-A), suggesting an autocrine role for EGFR in MPM. We checked on

Alfredo Cesario; Alessia Catassi; Luigi Festi; Andrea Imperatori; Andrea Pericelli; Domenico Galetta; Stefano Margaritora; Venanzio Porziella; Vittorio Cardaci; Pierluigi Granone; Lorenzo Dominioni; Patrizia Russo

2005-01-01

253

Polymorphisms in the syntaxin 17 gene are not associated with human cutaneous malignant melanoma  

Microsoft Academic Search

The prevalence of cutaneous malignant melanoma (CMM) has increased significantly in most Caucasian populations in recent decades. Both genetic and environmental risk factors are involved in the development of CMM. A germline mutation in the syntaxin 17 (STX17) gene of horses was recently identified, which causes premature hair graying and is associated with susceptibility to melanoma. We hypothesized that common

Zhen Zhen Zhao; David L. Duffy; Shane A. Thomas; Nicholas G. Martin; Nicholas K. Hayward; Grant W. Montgomery

2009-01-01

254

Notch-1 Signaling Promotes the Malignant Features of Human Breast Cancer through NF-?B Activation  

PubMed Central

The aberrant activation of Notch-1 signaling pathway has been proven to be associated with the development and progression of cancers. However, the specific roles and the underlying mechanisms of Notch-1 signaling pathway on the malignant behaviors of breast cancer are poorly understood. In this study, using multiple cellular and molecular approaches, we demonstrated that activation of Notch-1 signaling pathway promoted the malignant behaviors of MDA-MB-231 cells such as increased cell proliferation, colony formation, adhesion, migration, and invasion, and inhibited apoptosis; whereas deactivation of this signaling pathway led to the reversal of the aforementioned malignant cellular behaviors. Furthermore, we found that activation of Notch-1 signaling pathway triggered the activation of NF-?B signaling pathway and up-regulated the expression of NF-?B target genes including MMP-2/-9, VEGF, Survivin, Bcl-xL, and Cyclin D1. These results suggest that Notch-1 signaling pathway play important roles in promoting the malignant phenotype of breast cancer, which may be mediated partly through the activation of NF-?B signaling pathway. Our results further suggest that targeting Notch-1 signaling pathway may become a newer approach to halt the progression of breast cancer.

Li, Li; Zhao, Fenglong; Lu, Juan; Li, Tingting; Yang, Hong; Wu, Chunhui; Liu, Yiyao

2014-01-01

255

SERMs attenuate estrogen-induced malignant transformation of human mammary epithelial cells by upregulating detoxification of oxidative metabolites.  

PubMed

The risk of developing hormone-dependent cancers with long-term exposure to estrogens is attributed both to proliferative, hormonal actions at the estrogen receptor (ER) and to chemical carcinogenesis elicited by genotoxic, oxidative estrogen metabolites. Nontumorigenic MCF-10A human breast epithelial cells are classified as ER(-) and undergo estrogen-induced malignant transformation. Selective estrogen receptor modulators (SERM), in use for breast cancer chemoprevention and for postmenopausal osteoporosis, were observed to inhibit malignant transformation, as measured by anchorage-independent colony growth. This chemopreventive activity was observed to correlate with reduced levels of oxidative estrogen metabolites, cellular reactive oxygen species (ROS), and DNA oxidation. The ability of raloxifene, desmethylarzoxifene (DMA), and bazedoxifene to inhibit this chemical carcinogenesis pathway was not shared by 4-hydroxytamoxifen. Regulation of phase II rather than phase I metabolic enzymes was implicated mechanistically: raloxifene and DMA were observed to upregulate sulfotransferase (SULT 1E1) and glucuronidase (UGT 1A1). The results support upregulation of phase II metabolism in detoxification of catechol estrogen metabolites leading to attenuated ROS formation as a mechanism for inhibition of malignant transformation by a subset of clinically important SERMs. PMID:24598415

Hemachandra, L P Madhubhani P; Patel, Hitisha; Chandrasena, R Esala P; Choi, Jaewoo; Piyankarage, Sujeewa C; Wang, Shuai; Wang, Yijin; Thayer, Emily N; Scism, Robert A; Michalsen, Bradley T; Xiong, Rui; Siklos, Marton I; Bolton, Judy L; Thatcher, Gregory R J

2014-05-01

256

IgG heavy chain allotype (Gm), a genetic marker for human chromosome 14q32, and haematopoietic malignancies.  

PubMed Central

IgG heavy chain constant region allotypes, Gm, the genetic marker of human chromosome 14q32, are markers for susceptibility to certain diseases. We tested Gm allotypes in 365 patients with various types of haematological malignancies, 528 healthy controls and 35 healthy HTLV carriers. The frequency of specific Gm phenotypes was significantly increased in patients with adult onset null-ALL, AML, AMoL and CML in blastic crisis. Among these diseases, the frequency of Gm1,2,21 haplotype was significantly increased with adult onset null-ALL, AML and AMoL.

Nakao, Y; Matsumoto, H; Tsuji, K; Miyazaki, T; Masaoka, T; Nakayama, S; Kinoshita, K; Shingami, T; Matsui, T; Fujita, T

1984-01-01

257

Protective Role of Hsp27 Protein Against Gamma Radiation-Induced Apoptosis and Radiosensitization Effects of Hsp27 Gene Silencing in Different Human Tumor Cells  

SciTech Connect

Purpose: The ability of heat shock protein 27 (Hsp27) to protect cells from stressful stimuli and its increased levels in tumors resistant to anticancer therapeutics suggest that it may represent a target for sensitization to radiotherapy. In this study, we investigate the protective role of Hsp27 against radiation-induced apoptosis and the effect of its attenuation in highly expressing radioresistant cancer cell lines. Methods and Materials: We examined clonogenic death and the kinetics of apoptotic events in different tumor cell lines overexpressing or underexpressing Hsp27 protein irradiated with photons. The radiosensitive Jurkat cell line, which does not express Hsp27 constitutively or in response to {gamma}-rays, was stably transfected with Hsp27 complementary DNA. Attenuation of Hsp27 expression was accomplished by antisense or RNAi (interfering RNA) strategies in SQ20B head-and-neck squamous carcinoma, PC3 prostate cancer, and U87 glioblastoma radioresistant cells. Results: We measured concentration-dependent protection against the cytotoxic effects of radiation in Jurkat-Hsp27 cells, which led to a 50% decrease in apoptotic cells at 48 hours in the highest expressing cells. Underlying mechanisms leading to radiation resistance involved a significant increase in glutathione levels associated with detoxification of reactive oxygen species, a delay in mitochondrial collapse, and caspase activation. Conversely, attenuation of Hsp27 in SQ20B cells, characterized by their resistance to apoptosis, sensitizes cells to irradiation. This was emphasized by increased apoptosis, decreased glutathione basal level, and clonogenic cell death. Sensitization to irradiation was confirmed in PC3 and U87 radioresistant cells. Conclusion: Hsp27 gene therapy offers a potential adjuvant to radiation-based therapy of resistant tumors.

Aloy, Marie-Therese [Universite de Lyon 1, Laboratoire de Radiobiologie Cellulaire et Moleculaire, Faculte de Medecine Lyon-Sud, Oullins (France); Hospices Civils de Lyon, Service de Radiotherapie, Centre Hospitalier Lyon-Sud, Pierre-Benite (France)], E-mail: marie-therese.aloy@sante.univ-lyon1.fr; Hadchity, Elie; Bionda, Clara [Universite de Lyon 1, Laboratoire de Radiobiologie Cellulaire et Moleculaire, Faculte de Medecine Lyon-Sud, Oullins (France); Diaz-Latoud, Chantal [Universite de Lyon 1, UMR-CNRS-5534, Centre de Genetique Moleculaire et Cellulaire, Villeurbanne (France); Claude, Line; Rousson, Robert [Universite de Lyon 1, Laboratoire de Radiobiologie Cellulaire et Moleculaire, Faculte de Medecine Lyon-Sud, Oullins (France); Arrigo, Andre-Patrick [Universite de Lyon 1, UMR-CNRS-5534, Centre de Genetique Moleculaire et Cellulaire, Villeurbanne (France); Rodriguez-Lafrasse, Claire [Universite de Lyon 1, Laboratoire de Radiobiologie Cellulaire et Moleculaire, Faculte de Medecine Lyon-Sud, Oullins (France)

2008-02-01

258

The combination of olaparib and camptothecin for effective radiosensitization  

PubMed Central

Background Poly (ADP-ribose) polymerase-1 (PARP-1) is a key enzyme involved in the repair of radiation-induced single-strand DNA breaks. PARP inhibitors such as olaparib (KU-0059436, AZD-2281) enhance tumor sensitivity to radiation and to topoisomerase I inhibitors like camptothecin (CPT). Olaparib is an orally bioavailable inhibitor of PARP-1 and PARP-2 that has been tested in multiple clinical trials. The purpose of this study was to investigate the characteristics of the sensitizing effect of olaparib for radiation and CPT in order to support clinical application of this agent. Methods DLD-1 cells (a human colorectal cancer cell line) and H1299 cells (a non-small cell lung cancer cell line) with differences of p53 gene status were used. The survival of these cells was determined by clonogenic assay after treatment with drugs and X-ray irradiation. The ?H2AX focus formation assay was performed to examine the influence of olaparib on induction and repair of double-stranded DNA breaks after exposure to radiation or CPT. Results A radiosensitizing effect of olaparib was seen even at 0.01 ?M. Its radiosensitizing effect after exposure for 2 h was similar to that after 24 h. H1299 cells with depletion or mutation of p53 were more radioresistant than H1299 cells with wild-type p53. However, similar enhancement of radiosensitization by olaparib was observed with all of the tested cell lines regardless of the p53 status. Olaparib also sensitized cells to CPT. This sensitizing effect was seen at low concentrations of olaparib such as 0.01 ?M, and its sensitizing effect was the same at both 0.01 ?M and 1 ?M. The combination of olaparib and CPT had a stronger radiosensitizing effect. The results of the ?H2AX focus assay corresponded with the clonogenic assay findings. Conclusion Olaparib enhanced sensitivity to radiation and CPT at low concentrations and after relatively short exposure times such as 2 h. The radiosensitizing effect of olaprib was not dependent on the p53 status of tumor cells. These characteristics could be advantageous for clinical radiotherapy since tumor cells may be exposed to low concentrations of olaparib and/or may have different levels of p53 mutation. The combination of olaparib and CPT had a stronger radiosensitizing effect, indicating that combining a PARP inihibitor with a topoiomerase I inhibitor could be promising for clinical radiosensitization.

2012-01-01

259

In vitro and in vivo radiosensitization induced by hydroxyapatite nanoparticles  

PubMed Central

Background Previous study showed that hydroxyapatite nanoparticles (nano-HAPs) inhibited glioma growth in vitro and in vivo; and in a drug combination, they could reduce adverse reactions. We investigated the possible enhancement of radiosensitivity induced by nano-HAPs. Methods In vitro radiosensitization of nano-HAPs was measured using a clonogenic survival assay in human glioblastoma U251 and breast tumor brain metastatic tumor MDA-MB-231BR cells. DNA damage and repair were measured using ?H2AX foci, and mitotic catastrophe was determined by immunostaining. The effect of nano-HAPs on in vivo tumor radiosensitivity was investigated in a subcutaneous and an orthotopic model. Results Nano-HAPs enhanced each cell line's radiosensitivity when the exposure was 1 h before irradiation, and they had no significant effect on irradiation-induced apoptosis or on the activation of the G2 cell cycle checkpoint. The number of ?H2AX foci per cell was significantly large at 24 h after the combination modality of nano-HAPs + irradiation compared with single treatments. Mitotic catastrophe was also significantly increased at an interval of 72 h in tumor cells receiving the combined modality compared with the individual treatments. In a subcutaneous model, nano-HAPs caused a larger than additive increase in tumor growth delay. In an orthotopic model, nano-HAPs significantly reduced tumor growth and extended the prolongation of survival induced by irradiation. Conclusions These results show that nano-HAPs can enhance the radiosensitivity of tumor cells in vitro and in vivo through the inhibition of DNA repair, resulting in an increase in mitotic catastrophe.

Chu, Sheng-Hua; Karri, Surya; Ma, Yan-Bin; Feng, Dong-Fu; Li, Zhi-Qiang

2013-01-01

260

Improving Outcome in Malignant Pleural Mesothelioma (MPM) Using Pulsed- Protracted External Beam Radiation (PERT) and Intrapleural Delivery of Stem Cells.  

National Technical Information Service (NTIS)

Malignant Pleural Mesothelioma (MPM) survival remains poor despite multidisciplinary treatment involving aggressive surgery, chemotherapy and adjuvant radiotherapy (RT). The large RT treatment volume, and concerns about the proximity of radiosensitive nor...

B. Marples

2013-01-01

261

Improving Outcome in Malignant Pleural Mesothelioma (MPM) Using Pulsed- Protracted External Beam Radiation (PERT) and Intrapleural Delivery of Stem Cells.  

National Technical Information Service (NTIS)

Malignant Pleural Mesothelioma (MPM) survival remains poor despite multidisciplinary treatment involving aggressive surgery, chemotherapy and adjuvant radiotherapy (RT). The large RT treatment volume, and concerns about the proximity of radiosensitive nor...

B. Marples

2012-01-01

262

Radiosensitization by non-nitro compounds  

SciTech Connect

The effects of 23 non-vitro compounds on the radiosensitivity of hypoxic Chinese hamster V79-379A or E. coli AB 1157 cells in vitro are outlined. Imidazole derivatives substituted with several alternative electron-withdrawing groups are described; the dicyanovinyl function conferred considerable radiosensitizing activity. 2,4,5-Tribromoimidazole and 2,4-dinitrophenol may show unusual radiosensitizing activity because of interference with oxidative phosphorylation. Attempts to influence radiosensitivity by compounds potentially capable of depleting intracellular sulphydryls are also described.

Wardman, P. (Mount Vernon Hospital, Northwood, England); Anderson, R.F.; Hodgkiss, R.J.; Parrick, J.; Smithen, C.E.; Wallace, R.G.; Watts, M.E.

1982-03-01

263

Targeting the Interleukin-6/Jak/Stat Pathway in Human Malignancies  

PubMed Central

The Janus kinase/signal transducer and activator of transcription (Jak/Stat) pathway was discovered 20 years ago as a mediator of cytokine signaling. Since this time, more than 2,500 articles have been published demonstrating the importance of this pathway in virtually all malignancies. Although there are dozens of cytokines and cytokine receptors, four Jaks, and seven Stats, it seems that interleukin-6–mediated activation of Stat3 is a principal pathway implicated in promoting tumorigenesis. This transcription factor regulates the expression of numerous critical mediators of tumor formation and metastatic progression. This review will examine the relative importance and function of this pathway in nonmalignant conditions as well as malignancies (including tumor intrinsic and extrinsic), the influence of other Stats, the development of inhibitors to this pathway, and the potential role of inhibitors in controlling or eradicating cancers.

Sansone, Pasquale; Bromberg, Jacqueline

2012-01-01

264

Activating FGFR3 mutations cause mild hyperplasia in human skin, but are insufficient to drive benign or malignant skin tumors.  

PubMed

Fibroblast growth factor receptor 3 (FGFR3) activating mutations are drivers of malignancy in several human tissues, including bladder, lung, cervix, and blood. However, in skin, these mutations are associated predominantly with benign, common epidermal growths called seborrheic keratoses (SKs). How epidermis resists FGFR3 mediated transformation is unclear, but previous studies have suggested that FGFR3 activation in skin keratinocytes may serve a tumor-suppressive role by driving differentiation and antagonizing Ras signaling. To define the role of FGFR3 in human normal and neoplastic epidermis, and to directly test the hypothesis that FGFR3 antagonizes Ras, we engineered human skin grafts in vivo with mutant active FGFR3 or shRNA FGFR3 knockdown. We show that FGFR3 active mutants drive mild hyperproliferation, but are insufficient to support benign or malignant tumorigenesis, either alone, or in combination with G 1-S checkpoint release. This suggests that additional cell-intrinsic or stromal cues are required for formation of benign SKs with FGFR3 mutations. Further, FGFR3 activation does not alter the growth kinetics or differentiation status of engineered human epidermal SCCs driven by Ras, and FGFR3 protein itself is dispensable for Ras-driven SCC. To extend these findings to patients, we examined a uniquely informative human tumor in which SCC developed in continuity with a SK, raising the hypothesis that one of the tumors evolved from the other. However, mutational analysis from each tumor indicates that the overlapping SK and SCC evolved independently and supports our conclusion that FGFR3 activation is insufficient to drive SCC. PMID:24626198

Duperret, Elizabeth K; Oh, Seung Ja; McNeal, Andrew; Prouty, Stephen M; Ridky, Todd W

2014-05-15

265

Activation of the IGF-IR system contributes to malignant growth of human and mouse medulloblastomas  

Microsoft Academic Search

Insulin-like growth factor I receptor (IGF-IR) has been implicated in the normal and malignant growth of many cell types including cells from the central nervous system. In the cerebellar cortex IGF-IR mRNA is found in granular cells and IGF-I stimulation is mitogenic and protects cells from low-potassium-induced apoptosis. Since primitive neuroectodermal tumors\\/medulloblastomas (PNETs\\/medulloblastomas) are suspected to originate from the external

Jin Ying Wang; Luis Del Valle; Jennifer Gordon; Michele Rubini; Gaetano Romano; Sidney Croul; Francesca Peruzzi; Kamel Khalili; Krzysztof Reiss

2001-01-01

266

Oncolysis of malignant human melanoma tumors by Coxsackieviruses A13, A15 and A18  

Microsoft Academic Search

Many RNA viruses are displaying great promise in the field of oncolytic virotherapy. Previously, we reported that the picornavirus Coxsackievirus A21 (CVA21) possessed potent oncolytic activity against cultured malignant melanoma cells and melanoma xenografts in mice. In the present study, we demonstrate that three additional Group A Coxsackieviruses; Coxsackievirus A13 (CVA13), Coxsackievirus A15 (CVA15) and Coxsackievirus A18 (CVA18), also have

Gough G Au; Leone G Beagley; Erin S Haley; Richard D Barry; Darren R Shafren

2011-01-01

267

Phenotypic and gene expression diversity of malignant cells in human blast crisis chronic myeloid leukemia.  

PubMed

Chronic myeloid leukemia (CML) is considered as a paradigm of neoplasias developing through multistep track. It is believed that in the blast crisis (BC) terminal phase of the disease, blood-circulating blasts represent an expansion of a single CML clone. However, although these blasts grow mostly in suspension under standard culture conditions, a relatively small cell-fraction adheres to the plastic dish. Yet, it is unknown whether these two cell-fractions are distinct sub-populations that originated from a common CML clone and whether they have different biological and malignant properties. To address these questions, we have characterized the plastic-adherent and non-adherent sub-populations of various cell lines and primary cells derived from patients with CML in BC. This study indicated that the adherent-subsets retain repopulating ability with indications of increased malignant properties as greater anchorage-independent clonogenicity, impairment of cell-cell contact inhibition, loss of serum-dependent attenuation of plastic-adhesion, and a significant up-regulation of the oncogenes BCR-ABL, c-JUN, and c-FOS along with the adhesion-related genes KiSS-1, THBS3, and ITGB5. The adherent blasts stably retain their unique properties even after elimination of the adherence selection pressure. Sub-cloning analyses indicated that the adherent cells could be continuously evolved from any parental non-adherent clone in a unidirectional manner. This study provides new insights into the biology and the malignant evolution of CML, indicating that at the BC phase, circulating blasts are heterogeneous and consisting of at least two distinct populations of a common clonal origin. The existence of a minor "pool" of blasts of greater clonogenic capacity along with significantly higher expression level of BCR-ABL, individually or in conjunction with other cancer and adhesion-related genes, might also signify clonal evolution toward subsequent increased malignancy and lower therapeutic sensitivity. PMID:18452548

Simanovsky, Masha; Berlinsky, Sagi; Sinai, Pirchia; Leiba, Merav; Nagler, Arnon; Galski, Hanan

2008-10-01

268

Comparative analysis of cell death induction by Taurolidine in different malignant human cancer cell lines  

PubMed Central

Background Taurolidine (TRD) represents an anti-infective substance with anti-neoplastic activity in many malignant cell lines. So far, the knowledge about the cell death inducing mechanisms and pathways activated by TRD is limited. The aim of this study was therefore, to perform a comparative analysis of cell death induction by TRD simultaneously in different malignant cell lines. Materials and methods Five different malignant cell lines (HT29/Colon, Chang Liver/Liver, HT1080/fibrosarcoma, AsPC-1/pancreas and BxPC-3/pancreas) were incubated with increasing concentrations of TRD (100 ?M, 250 ?M and 1000 ?M) for 6 h and 24 h. Cell viability, apoptosis and necrosis were analyzed by FACS analysis (Propidiumiodide/AnnexinV staining). Additionally, cells were co-incubated with the caspase Inhibitor z-VAD, the radical scavenger N-Acetylcystein (NAC) and the Gluthation depleting agent BSO to examine the contribution of caspase activation and reactive oxygen species in TRD induced cell death. Results All cell lines were susceptible to TRD induced cell death without resistance toward this anti-neoplastic agent. However, the dose response effects were varying largely between different cell lines. The effect of NAC and BSO co-treatment were highly different among cell lines - suggesting a cell line specific involvement of ROS in TRD induced cell death. Furthermore, impact of z-VAD mediated inhibition of caspases was differing strongly among the cell lines. Conclusion This is the first study providing a simultaneous evaluation of the anti-neoplastic action of TRD across several malignant cell lines. The involvement of ROS and caspase activation was highly variable among the five cell lines, although all were susceptible to TRD induced cell death. Our results indicate, that TRD is likely to provide multifaceted cell death mechanisms leading to a cell line specific diversity.

2010-01-01

269

FT-IR Spectroscopic Analysis of Normal and Malignant Human Oral Tissues  

NASA Astrophysics Data System (ADS)

FT-IR spectroscopy has been used to explore the changes in the vibrational bands of normal and oral squamous cell carcinoma (OSCC) tissues in the region 4000-400 cm-1. Significant changes in the spectral features were observed. The spectral changes were the results of characteristics structural alterations at the molecular level in the malignant tissues. These alterations include structural changes of proteins and possible increase of its content, an increase in the nucleic-to-cytoplasm ratio, an increase in the relative amount of DNA, an increase in the rate of phosphorylation process induced by carcinogenesis, a loss of hydrogen bonding of the C-OH groups in the amino acid residues of proteins, a decrease in the relative amount of lipids compared to normal epithelial oral tissues. The results of the present study demonstrate that the FT-IR technique has the feasibility of discriminating malignant from normal tissues and other pathological states in a short period of time and may detect malignant transformation earlier than the standard histological examination stage.

Krishnakumar, N.; Madhavan, R. Nirmal; Sumesh, P.; Palaniappan, Pl. Rm.; Venkatachalam, P.; Ramachandran, C. R.

2008-11-01

270

Establishment of a new human pleomorphic malignant fibrous histiocytoma cell line, FU-MFH-2: molecular cytogenetic characterization by multicolor fluorescence in situ hybridization and comparative genomic hybridization  

Microsoft Academic Search

BACKGROUND: Pleomorphic malignant fibrous histiocytoma (MFH) is one of the most frequent malignant soft tissue tumors in adults. Despite the considerable amount of research on MFH cell lines, their characterization at a molecular cytogenetic level has not been extensively analyzed. METHODS AND RESULTS: We established a new permanent human cell line, FU-MFH-2, from a metastatic pleomorphic MFH of a 72-year-old

Jun Nishio; Hiroshi Iwasaki; Kazuki Nabeshima; Masako Ishiguro; Teruto Isayama; Masatoshi Naito

2010-01-01

271

AIDS-Related Malignancies  

Microsoft Academic Search

OVERVIEW OF MALIGNANCY IN PATIENTS WITH AIDS Despite the advent of highly active antiretroviral therapy, the incidence of human immunodeficiency virus (HIV)-asso- ciated malignancies has not decreased. The United States Centers for Disease Control (CDC) has determined that Kaposi's sarcoma, non-Hodgkin's lymphoma (including pri- mary central nervous system lymphoma), and cervical carci- noma define the acquired immune deficiency syndrome (AIDS).

G. MICHAEL WOOL

272

Gene expression profiling of human adrenocortical tumors using complementary deoxyribonucleic Acid microarrays identifies several candidate genes as markers of malignancy.  

PubMed

The aim of this study was to identify predictor sets of genes whose over- or underexpression in human sporadic adrenocortical tumors would help to identify malignant vs. benign tumors and to predict postsurgical metastatic recurrence. For this, we analyzed the expression of 230 candidate genes using cDNA microarrays in a series of 57 well-characterized human sporadic adrenocortical tumors (33 adenomas and 24 carcinomas). We identified two clusters of genes (the IGF-II cluster containing eight genes, including IGF-II, and the steroidogenesis cluster containing six genes encoding steroidogenic enzymes plus eight other genes) whose combined levels of expression appeared to be good predictors of malignancy. This predictive value was as strong as that of the pathological score of Weiss. The analysis of the population of carcinomas (13 tumors) for genes whose expression would be strongly different between recurring and nonrecurring tumors allowed identification of 14 genes meeting these criteria. Among these genes, there are probably new markers of tumor evolution that will deserve additional validation on a larger scale. Taken together, these results show that the parallel analysis of the expression levels of a selected group of genes on microgram quantities of tumor RNA (a quantity that can be obtained from fine needle aspirations) appears as a complementary method to histopathology for the diagnosis and prognosis of evolution of adrenocortical carcinomas. PMID:15613424

de Fraipont, Florence; El Atifi, Michelle; Cherradi, Nadia; Le Moigne, Gwennaelle; Defaye, Geneviève; Houlgatte, Rémi; Bertherat, Jérôme; Bertagna, Xavier; Plouin, Pierre-François; Baudin, Eric; Berger, François; Gicquel, Christine; Chabre, Olivier; Feige, Jean-Jacques

2005-03-01

273

An antibody-based multifaceted approach targeting the human transferrin receptor for the treatment of B-cell malignancies.  

PubMed

We previously developed an antibody-avidin fusion protein (ch128.1Av) targeting the human transferrin receptor 1 (TfR1, also known as CD71), which demonstrates direct in vitro cytotoxicity against malignant hematopoietic cells. This cytotoxicity is attributed to its ability to decrease the level of TfR1 leading to lethal iron deprivation. We now report that ch128.1Av shows the ability to bind the Fc? receptors and the complement component C1q, suggesting that it is capable of eliciting Fc-mediated effector functions such as antibody-dependent cell-mediated cytotoxicity and complement-mediated cytotoxicity. In addition, in 2 disseminated multiple myeloma xenograft mouse models, we show that a single dose of ch128.1Av results in significant antitumor activity, including long-term survival. It is interesting to note that the parental antibody without avidin (ch128.1) also shows remarkable in vivo anticancer activity despite its limited in vitro cytotoxicity. Finally, we demonstrate that ch128.1Av is not toxic to pluripotent hematopoietic progenitor cells using the long-term cell-initiating culture assay suggesting that these important progenitors would be preserved in different therapeutic approaches, including the in vitro purging of cancer cells for autologous transplantation and in vivo passive immunotherapy. Our results suggest that ch128.1Av and ch128.1 may be effective in the therapy of human multiple myeloma and potentially other hematopoietic malignancies. PMID:21654517

Daniels, Tracy R; Ortiz-Sánchez, Elizabeth; Luria-Pérez, Rosendo; Quintero, Rafaela; Helguera, Gustavo; Bonavida, Benjamin; Martínez-Maza, Otoniel; Penichet, Manuel L

2011-01-01

274

Sorafenib tosylate as a radiosensitizer in malignant astrocytoma.  

PubMed

Progress in research on the molecular aspects of glioblastoma has yet to provide a medical therapy that significantly improves prognosis. Glioblastoma invariably progress through current treatment regimens with radiotherapy as a key component. Activation of several signaling pathways is thought to be associated with this resistance to radiotherapy. Ras activity is exceptionally high in glioblastoma and may regulate sensitivity to radiotherapy. Raf-1, a downstream effector of Ras, demonstrates a high amount of activity in glioblastoma. Therefore, Raf-1 inhibition should be considered as a mechanism to increase the effectiveness of radiotherapy in treatment regimen. In vitro analysis was performed with a novel Raf-1 kinase inhibitor (BAY 54-9085) in culture with the glioblastoma cell line U1242. The cell line was treated in serum-containing media and analyzed for the effect of the BAY 54-9085 alone and BAY 54-9085 combined with radiation on cell death. BAY 54-9085 displayed a cytocidal effect on glioblastoma cells following a 3 day incubation with the drug in serum-containing media. A dose of 2.5 ?M displayed moderate cell death which significantly increased with a dose of 5.0 ?M. In addition, glioblastoma cells treated with both the BAY 54-9085 and gamma radiation displayed a significant increase in cell death (85.5%) as compared to either BAY 54-9085 (73.1%) or radiation (34.4%) alone. Radiation therapy is a key component of treatment for glioblastoma. A novel Raf-1 inhibitor displayed in vitro evidence of synergistically increasing cell death of glioblastoma cells in combination with radiation. PMID:24139873

Sherman, Jonathan H; Kirzner, Jared; Siu, Alan; Amos, Samson; Hussaini, Isa M

2014-01-01

275

Deregulation of cancer-related miRNAs is a common event in both benign and malignant human breast tumors.  

PubMed

MicroRNAs (miRNAs) are endogenous non-coding RNAs, which play an essential role in the regulation of gene expression during carcinogenesis. The role of miRNAs in breast cancer has been thoroughly investigated, and although many miRNAs are identified as cancer related, little is known about their involvement in benign tumors. In this study, we investigated miRNA expression profiles in the two most common types of human benign tumors (fibroadenoma/fibroadenomatosis) and in malignant breast tumors and explored their role as oncomirs and tumor suppressor miRNAs. Here, we identified 33 miRNAs with similar deregulated expression in both benign and malignant tumors compared with the expression levels of those in normal tissue, including breast cancer-related miRNAs such as let-7, miR-21 and miR-155. Additionally, messenger RNA (mRNA) expression profiles were obtained for some of the same samples. Using integrated mRNA/miRNA expression analysis, we observed that overexpression of certain miRNAs co-occurred with a significant downregulation of their candidate target mRNAs in both benign and malignant tumors. In support of these findings, in vitro functional screening of the downregulated miRNAs in non-malignant and breast cancer cell lines identified several possible tumor suppressor miRNAs, including miR-193b, miR-193a-3p, miR-126, miR-134, miR-132, miR-486-5p, miR-886-3p, miR-195 and miR-497, showing reduced growth when re-expressed in cancer cells. The finding of deregulated expression of oncomirs and tumor suppressor miRNAs in benign breast tumors is intriguing, indicating that they may play a role in proliferation. A role of cancer-related miRNAs in the early phases of carcinogenesis and malignant transformation can, therefore, not be ruled out. PMID:24104550

Tahiri, Andliena; Leivonen, Suvi-Katri; Lüders, Torben; Steinfeld, Israel; Ragle Aure, Miriam; Geisler, Jürgen; Mäkelä, Rami; Nord, Silje; Riis, Margit L H; Yakhini, Zohar; Kleivi Sahlberg, Kristine; Børresen-Dale, Anne-Lise; Perälä, Merja; Bukholm, Ida R K; Kristensen, Vessela N

2014-01-01

276

GPER mediates estrogen-induced signaling and proliferation in human breast epithelial cells and normal and malignant breast.  

PubMed

17?-Estradiol (estrogen), through receptor binding and activation, is required for mammary gland development. Estrogen stimulates epithelial proliferation in the mammary gland, promoting ductal elongation and morphogenesis. In addition to a developmental role, estrogen promotes proliferation in tumorigenic settings, particularly breast cancer. The proliferative effects of estrogen in the normal breast and breast tumors are attributed to estrogen receptor ?. Although in vitro studies have demonstrated that the G protein-coupled estrogen receptor (GPER, previously called GPR30) can modulate proliferation in breast cancer cells both positively and negatively depending on cellular context, its role in proliferation in the intact normal or malignant breast remains unclear. Estrogen-induced GPER-dependent proliferation was assessed in the immortalized nontumorigenic human breast epithelial cell line, MCF10A, and an ex vivo organ culture model employing human breast tissue from reduction mammoplasty or tumor resections. Stimulation by estrogen and the GPER-selective agonist G-1 increased the mitotic index in MCF10A cells and proportion of cells in the cell cycle in human breast and breast cancer explants, suggesting increased proliferation. Inhibition of candidate signaling pathways that may link GPER activation to proliferation revealed a dependence on Src, epidermal growth factor receptor transactivation by heparin-bound EGF and subsequent ERK phosphorylation. Proliferation was not dependent on matrix metalloproteinase cleavage of membrane-bound pro-HB-EGF. The contribution of GPER to estrogen-induced proliferation in MCF10A cells and breast tissue was confirmed by the ability of GPER-selective antagonist G36 to abrogate estrogen- and G-1-induced proliferation, and the ability of siRNA knockdown of GPER to reduce estrogen- and G-1-induced proliferation in MCF10A cells. This is the first study to demonstrate GPER-dependent proliferation in primary normal and malignant human tissue, revealing a role for GPER in estrogen-induced breast physiology and pathology. PMID:24718936

Scaling, Allison L; Prossnitz, Eric R; Hathaway, Helen J

2014-06-01

277

COX-2 overexpression increases malignant potential of human glioma cells through Id1.  

PubMed

Increased COX-2 expression directly correlates with glioma grade and is associated with shorter survival in glioblastoma (GBM) patients. COX-2 is also regulated by epidermal growth factor receptor signaling which is important in the pathogenesis of GBMs. However, COX-2 expression has not been previously shown to directly alter malignancy of GBMs. Id1 is a member of the helix-loop-helix (HLH) family of transcriptional repressors that act as dominant-negative inhibitors of basic-HLH factors. This factor has been shown to be regulated by COX-2 in breast carcinoma cells and recent studies suggest that Id1 may also be involved in the genesis/progression of gliomas. We now show that COX-2 increases the aggressiveness of GBM cells. GBM cells with COX-2 overexpression show increased growth of colonies in soft agar. Tumorigenesis in vivo is also increased in both subcutaneous flank and orthotopic intracranial tumor models. COX-2 overexpression induces Id1 expression in two GBM cell lines suggesting a role for Id1 in glioma transformation/tumorigenesis. Furthermore, we find direct evidence of a role for Id1 with significant suppression of in vitro transformation and in vivo tumorigenesis in COX-2-overexpressing GBM cells where Id1 has been knocked down. In fact, Id1 is even more efficient at enhancing transformation/tumorigenesis of GBM cells than COX-2. Finally, GBM cells with COX-2 or Id1 overexpression show greater migration/invasive potential and tumors that arise from these cells also display increased microvessel density, results in line with the increased malignant potential seen in these cells. Thus, COX-2 enhances the malignancy of GBM cells through induction of Id1. PMID:24659686

Xu, Kaiming; Wang, Lanfang; Shu, Hui-Kuo G

2014-03-15

278

COX-2 overexpression increases malignant potential of human glioma cells through Id1  

PubMed Central

Increased COX-2 expression directly correlates with glioma grade and is associated with shorter survival in glioblastoma (GBM) patients. COX-2 is also regulated by epidermal growth factor receptor signaling which is important in the pathogenesis of GBMs. However, COX-2 expression has not been previously shown to directly alter malignancy of GBMs. Id1 is a member of the helix-loop-helix (HLH) family of transcriptional repressors that act as dominant-negative inhibitors of basic-HLH factors. This factor has been shown to be regulated by COX-2 in breast carcinoma cells and recent studies suggest that Id1 may also be involved in the genesis/progression of gliomas. We now show that COX-2 increases the aggressiveness of GBM cells. GBM cells with COX-2 overexpression show increased growth of colonies in soft agar. Tumorigenesis in vivo is also increased in both subcutaneous flank and orthotopic intracranial tumor models. COX-2 overexpression induces Id1 expression in two GBM cell lines suggesting a role for Id1 in glioma transformation/tumorigenesis. Furthermore, we find direct evidence of a role for Id1 with significant suppression of in vitro transformation and in vivo tumorigenesis in COX-2-overexpressing GBM cells where Id1 has been knocked down. In fact, Id1 is even more efficient at enhancing transformation/tumorigenesis of GBM cells than COX-2. Finally, GBM cells with COX-2 or Id1 overexpression show greater migration/invasive potential and tumors that arise from these cells also display increased microvessel density, results in line with the increased malignant potential seen in these cells. Thus, COX-2 enhances the malignancy of GBM cells through induction of Id1.

Xu, Kaiming; Wang, Lanfang; Shu, Hui-Kuo G.

2014-01-01

279

A Dimeric Mutant of Human Pancreatic Ribonuclease with Selective Cytotoxicity toward Malignant Cells  

NASA Astrophysics Data System (ADS)

Monomeric human pancreatic RNase, devoid of any biological activity other than its RNA degrading ability, was engineered into a dimeric protein with a cytotoxic action on mouse and human tumor cells, but lacking any appreciable toxicity on mouse and human normal cells. This dimeric variant of human pancreas RNase selectively sensitizes to apoptotic death cells derived from a human thyroid tumor. Because of its selectivity for tumor cells, and because of its human origin, this protein represents a potentially very attractive, novel tool for anticancer therapy.

Piccoli, Renata; di Gaetano, Sonia; de Lorenzo, Claudia; Grauso, Michela; Monaco, Carmen; Spalletti-Cernia, Daniela; Laccetti, Paolo; Cinatl, Jaroslav; Matousek, Josef; D'Alessio, Giuseppe

1999-07-01

280

Proteomic and Bioinformatic Analysis of mSWI/SNF (BAF) Complexes Reveals Extensive Roles in Human Malignancy  

PubMed Central

Subunits of mammalian SWI/SNF (mSWI/SNF, also called BAF) complexes have recently been implicated as tumor suppressors in a number of human malignancies. To understand the full extent of their involvement, we conducted a proteomic analysis of purified endogenous mSWI/SNF complexes. Our studies revealed several new dedicated, stable subunits not found in the yeast SWI/SNF complex including Bcl7a, b and c, Bcl11a and b, Brd9 and SS18. Incorporating these novel members, we determined the frequency of mSWI/SNF subunit mutations in recent exome- and whole-genome sequencing studies of primary human tumors. Surprisingly, mSWI/SNF subunits are mutated in 19.6% of all human tumors reported in 44 exome sequencing studies. Our analysis suggests that specific subunits protect against cancer in specific tissues. In addition, we find that mutations to more than one subunit, which we define as a type of compound heterozygosity, are prevalent in certain cancers. Our studies demonstrate that mSWI/SNF is the most frequently mutated chromatin-regulatory complex (CRC) in human cancer and that in contrast to other known tumor suppressors and oncogenes surveyed, mSWI/SNF is broadly mutated, similar to TP53. Thus, proper functioning of these polymorphic chromatin regulatory complexes may constitute a major mechanism of human tumor suppression.

Kadoch, Cigall; Hargreaves, Diana C.; Hodges, Courtney; Elias, Laura; Ho, Lena; Ranish, Jeff; Crabtree, Gerald R.

2013-01-01

281

Phototoxic effects of hematoporphyrin derivative and its chromatographic fractions on hormone-producing human malignant trophoblast cells in vitro.  

PubMed

The in vitro phototoxicity of HPD on malignant cells relative to normal cells has been examined. Two human malignant cell lines were studied: the BeWo line of choriocarcinoma cells, which secrete the tumor marker human chorionic gonadotropin (hCG) and its alpha-subunit; and the CaSki line of human cervical carcinoma cells, which secrete hCG and its beta-subunit. Trophoblast-derived, hCG-secreting cells from human amniotic fluid were used as normal controls. In all experiments with HPD plus light, a close correlation was found 24 h after light between cell number and RIA-detectable marker concentration in the medium. Phototoxicity was greater when HPD was introduced in serum-free rather than serum-containing medium. No toxicity was observed in light and dark controls. Cells in Leighton tubes were incubated 1 h with HPD (25 micrograms/ml) in serum-free medium, then rinsed and incubated with medium containing 10% serum. At 2 and 3 days after contact with HPD, flasks were exposed to cool white fluorescent light (1 mW/cm2) for 5 min. Viable cell counts taken 1 day after the light dose indicated that HPD is significantly more phototoxic to BeWo than to CaSki cells; and that both malignant cell types are more photosensitive than amniotic fluid cells, presumably because the latter retain HPD less effectively. In another aspect of this work BeWo cells were used as a model system for comparing the phototoxic effects of the fast (F) and slow (S) eluting fractions of HPD obtained by Bio-Gel P-10 chromatography. Cells in light-shielded tubes were sensitized by incubating with porphyrins for 20 h in media containing 10% calf serum. At 2, 3, or 4 days after removal of porphyrin, with daily replacement of serum-containing medium, flasks were irradiated (see above), and then incubated in the dark for 2 to 4 additional days. Daily culture fluids were analyzed for hormone levels (hCG alpha), and cell counts were performed 2 or 3 days after the light dose. HPD-S (25 micrograms/ml) had no effect on either hormone secretion or cell viability in any of the flasks, whether exposed to light or not. HPD-F at low concentrations (0.25 or 2.5 micrograms/ml) had no detectable effect on cell count or hormone secretion in irradiated flasks. At 10 micrograms/ml, HPD-F was innocuous in dark controls, but caused a large decrease in cell count and hormone output in irradiated flasks.(ABSTRACT TRUNCATED AT 400 WORDS) PMID:2937259

Girotti, A W; Hussa, R O

1985-01-01

282

Competitive but Not Allosteric mTOR Kinase Inhibition Enhances Tumor Cell Radiosensitivity.  

PubMed

The mechanistic target of rapamycin (mTOR) is a critical kinase in the regulation of gene translation and has been suggested as a potential target for radiosensitization. The goal of this study was to compare the radiosensitizing activities of the allosteric mTOR inhibitor rapamycin with that of the competitive mTOR inhibitor PP242. On the basis of immunoblot analyses, whereas rapamycin only partially inhibited mTOR complex 1 (mTORC1) activity and had no effect on mTOR complex 2 (mTORC2), PP242 inhibited the activity of both mTOR-containing complexes. Irradiation alone had no effect on mTORC1 or mTORC2 activity. Clonogenic survival was used to define the effects of the mTOR inhibitors on in vitro radiosensitivity. In the two tumor cell lines evaluated, PP242 treatment 1 hour before irradiation increased radiosensitivity, whereas rapamycin had no effect. Addition of PP242 after irradiation also enhanced the radiosensitivity of both tumor lines. To investigate the mechanism of radiosensitization, the induction and repair of DNA double-strand breaks were evaluated according ?H2AX foci. PP242 exposure did not influence the initial level of ?H2AX foci after irradiation but did significantly delay the dispersal of radiation-induced ?H2AX foci. In contrast to the tumor cell lines, the radiosensitivity of a normal human fibroblast cell line was not influenced by PP242. Finally, PP242 administration to mice bearing U251 xenografts enhanced radiation-induced tumor growth delay. These results indicate that in a preclinical tumor model PP242 enhances tumor cell radiosensitivity both in vitro and in vivo and suggest that this effect involves an inhibition of DNA repair. PMID:23730416

Hayman, Thomas J; Kramp, Tamalee; Kahn, Jenna; Jamal, Muhammad; Camphausen, Kevin; Tofilon, Philip J

2013-06-01

283

Competitive but Not Allosteric mTOR Kinase Inhibition Enhances Tumor Cell Radiosensitivity1  

PubMed Central

The mechanistic target of rapamycin (mTOR) is a critical kinase in the regulation of gene translation and has been suggested as a potential target for radiosensitization. The goal of this study was to compare the radiosensitizing activities of the allosteric mTOR inhibitor rapamycin with that of the competitive mTOR inhibitor PP242. On the basis of immunoblot analyses, whereas rapamycin only partially inhibited mTOR complex 1 (mTORC1) activity and had no effect on mTOR complex 2 (mTORC2), PP242 inhibited the activity of both mTOR-containing complexes. Irradiation alone had no effect on mTORC1 or mTORC2 activity. Clonogenic survival was used to define the effects of the mTOR inhibitors on in vitro radiosensitivity. In the two tumor cell lines evaluated, PP242 treatment 1 hour before irradiation increased radiosensitivity, whereas rapamycin had no effect. Addition of PP242 after irradiation also enhanced the radiosensitivity of both tumor lines. To investigate the mechanism of radiosensitization, the induction and repair of DNA double-strand breaks were evaluated according ?H2AX foci. PP242 exposure did not influence the initial level of ?H2AX foci after irradiation but did significantly delay the dispersal of radiation-induced ?H2AX foci. In contrast to the tumor cell lines, the radiosensitivity of a normal human fibroblast cell line was not influenced by PP242. Finally, PP242 administration to mice bearing U251 xenografts enhanced radiation-induced tumor growth delay. These results indicate that in a preclinical tumor model PP242 enhances tumor cell radiosensitivity both in vitro and in vivo and suggest that this effect involves an inhibition of DNA repair.

Hayman, Thomas J; Kramp, Tamalee; Kahn, Jenna; Jamal, Muhammad; Camphausen, Kevin; Tofilon, Philip J

2013-01-01

284

G2 chromosomal radiosensitivity of ataxia-telangiectasia heterozygotes  

SciTech Connect

Five lines of skin fibroblasts from individuals heterozygous for ataxia-telangiectasia (A-T), compared with six cell lines from age-matched normal controls, show a much higher frequency of chromatid breaks and gaps following x-irradiation during the G2 phase of the cell cycle. The magnitude of this difference suggests that G2 chromatid radiosensitivity could provide the basis for an assay to detect A-T heterozygotes. Though clinically normal, A-T heterozygotes share a high risk of cancer with A-T homozygotes and constitute approximately 1% of the human population. Further, we propose that G2 chromosomal radiosensitivity, which appears to result from a DNA repair deficiency, may be associated with a genetic predisposition to cancer.

Parshad, R.; Sanford, K.K.; Jones, G.M.; Tarone, R.E.

1985-01-01

285

Toll-like receptors: lessons to learn from normal and malignant human B cells  

PubMed Central

The humoral immune system senses microbes via recognition of specific microbial molecular motifs by Toll-like receptors (TLRs). These encounters promote plasma cell differentiation and antibody production. Recent studies have demonstrated the importance of the TLR system in enhancing antibody-mediated defense against infections and maintaining memory B cells. These results have led the way to the design of vaccines that target B cells by engaging TLRs. In hematologic malignancies, cells often retain B cell–specific receptors and associated functions. Among these, TLRs are currently exploited to target different subclasses of B-cell leukemia, and TLR agonists are currently being evaluated in clinical trials. However, accumulating evidence suggests that endogenous TLR ligands or chronic infections promote tumor growth, thus providing a need for further investigations to decipher the exact function of TLRs in the B-cell lineage and in neoplastic B cells. The aim of this review is to present and discuss the latest advances with regard to the expression and function of TLRs in both healthy and malignant B cells. Special attention will be focused on the growth-promoting effects of TLR ligands on leukemic B cells and their potential clinical impact.

Chiron, David; Bekeredjian-Ding, Isabelle; Pellat-Deceunynck, Catherine; Bataille, Regis

2008-01-01

286

Expression of the c-mpl proto-oncogene in human hematologic malignancies.  

PubMed

Similar to two other hematopoietic growth factor receptors, the c-fms (macrophage colony-stimulating factor receptor) and the c-kit genes, c-mpl has been discovered through the study of oncogenic retroviruses. Unlike c-fms and c-kit, which both belong to a subgroup of tyrosine kinase receptors, the c-mpl proto-oncogene encodes a new member of the cytokine receptor superfamily. We have studied the expression of c-mpl in a series of 105 patients with hematologic malignancies using Northern blot analysis. The levels of c-mpl transcripts in lymphoid malignancies and in chronic myeloproliferative disorders were not significantly different from those found in normal bone marrow cells, in which c-mpl was barely detectable. In contrast, c-mpl expression was increased in 26 of 51 patients with acute myeloblastic leukemia (AML) and in 5 of 16 patients with myelodysplastic syndromes. Amplification of the c-mpl gene was detected in genomic DNA of one M4 AML patient. There was no significant correlation between c-mpl expression and the French-American-British classification of AML. Patients with high c-mpl expression appeared to belong to a subgroup of AML with a low rate of complete remission and a poor prognosis, including secondary leukemia and AML with unfavorable cytogenetic abnormalities. PMID:8393355

Vigon, I; Dreyfus, F; Melle, J; Viguié, F; Ribrag, V; Cocault, L; Souyri, M; Gisselbrecht, S

1993-08-01

287

NANOG promoter methylation and expression correlation during normal and malignant human germ cell development  

PubMed Central

Testicular germ cell tumors are the most frequent malignant tumors in young Caucasian males, with increasing incidence. The actual model of tumorigenesis is based on the theory that a block in maturation of fetal germ cells lead to formation of the intratubular germ cell neoplasia unclassified. Early fetal germ cells and undifferentiated germ cell tumors express pluripotency markers such as the transcription factor NANOG. It has been demonstrated that epigenetic modifications, such as promoter DNA methylation, are able to silence gene expression in normal and cancer cells. Here we show that OCT3/4-SOX2 mediated expression of NANOG can be silenced by methylation of promoter CpG-sites. We found that global methylation of DNA decreased from fetal spermatogonia to mature sperm. In contrast, CpGs in the NANOG promoter were found hypomethylated in spermatogonia and hypermethylated in sperm. This selective repression might reflect the cells need to suppress pluripotency in order to prevent malignant transformation. Finally, methylation of CpGs in the NANOG promoter in germ cell tumors and derived cell lines correlated to differentiation state.

Nettersheim, Daniel; Bierman, Katharina; Gillis, Ad JM; Steger, Klaus; Looijenga, Leendert HJ

2011-01-01

288

Transcutaneous application of CO2 enhances the antitumor effect of radiation therapy in human malignant fibrous histiocytoma.  

PubMed

Sarcomas are relatively resistant because of hypoxia. We previously demonstrated that the transcutaneous CO(2) therapy reduced hypoxic conditions in human malignant fibrous histiocytoma (MFH). Therefore, we hypothesized that transcutaneous CO(2) therapy could enhance the antitumor effect of radiation therapy in human MFH. Our purpose was to evaluate the effects of transcutaneous CO(2) therapy on the antitumor efficacy of X-ray irradiation using MFH. First, in an in vitro study, we assessed apoptotic activity and reactive oxygen species (ROS) production using flow cytometric and immunoblot analysis at 24 h after X-ray irradiation under three different oxygen conditions (normoxic, reoxygenated and hypoxic). In addition, in the in vivo study, 24 male athymic BALB/c nude mice with MFH tumors that were inoculated in the dorsal subcutaneous area were randomized into four groups: control, CO(2), X-ray irradiation and combination (CO(2) and X-ray irradiation). Treatments were performed twice weekly for 2 weeks, four times in total. Tumor volume was calculated. All tumors were excised and apoptotic activity, ROS production, related proteins and HIF-1? expression were assessed using flow cytometric and immunoblot analysis. The in vitro study revealed that X-ray irradiation induced increased apoptosis and ROS production in MFH cells under normoxic and reoxygenated conditions relative to hypoxic conditions (P<0.01). In the in vivo study, tumor volume in the combination group was reduced to 28, 42 and 47% of that in the control, CO(2), and X-ray groups, respectively (P<0.05). Apoptotic activity and ROS production in the combination group were strongly increased with decreasing HIF-1? expression relative to the control, CO(2) and X-ray groups. The transcutaneous CO(2) system enhanced the antitumor action of X-ray irradiation and could be a novel therapeutic tool for overcoming radio-resistance in human malignancies. PMID:24889546

Onishi, Yasuo; Akisue, Toshihiro; Kawamoto, Teruya; Ueha, Takeshi; Hara, Hitomi; Toda, Mitsunori; Harada, Risa; Minoda, Masaya; Morishita, Masayuki; Sasaki, Ryohei; Nishida, Kotaro; Kuroda, Ryosuke; Kurosaka, Masahiro

2014-08-01

289

Horizontal transmission of malignancy: in-vivo fusion of human lymphomas with hamster stroma produces tumors retaining human genes and lymphoid pathology.  

PubMed

We report the in-vivo fusion of two Hodgkin lymphomas with golden hamster cheek pouch cells, resulting in serially-transplanted (over 5-6 years) GW-532 and GW-584 heterosynkaryon tumor cells displaying both human and hamster DNA (by FISH), lymphoma-like morphology, aggressive metastasis, and retention of 7 human genes (CD74, CXCR4, CD19, CD20, CD71, CD79b, and VIM) out of 24 tested by PCR. The prevalence of B-cell restricted genes (CD19, CD20, and CD79b) suggests that this uniform population may be the clonal initiating (malignant) cells of Hodgkin lymphoma, despite their not showing translation to their respective proteins by immunohistochemical analysis. This is believed to be the first report of in-vivo cell-cell fusion of human lymphoma and rodent host cells, and may be a method to disclose genes regulating both organoid and metastasis signatures, suggesting that the horizontal transfer of tumor DNA to adjacent stromal cells may be implicated in tumor heterogeneity and progression. The B-cell gene signature of the hybrid xenografts suggests that Hodgkin lymphoma, or its initiating cells, is a B-cell malignancy. PMID:23405135

Goldenberg, David M; Gold, David V; Loo, Meiyu; Liu, Donglin; Chang, Chien-Hsing; Jaffe, Elaine S

2013-01-01

290

Horizontal Transmission of Malignancy: In-Vivo Fusion of Human Lymphomas with Hamster Stroma Produces Tumors Retaining Human Genes and Lymphoid Pathology  

PubMed Central

We report the in-vivo fusion of two Hodgkin lymphomas with golden hamster cheek pouch cells, resulting in serially-transplanted (over 5–6 years) GW-532 and GW-584 heterosynkaryon tumor cells displaying both human and hamster DNA (by FISH), lymphoma-like morphology, aggressive metastasis, and retention of 7 human genes (CD74, CXCR4, CD19, CD20, CD71, CD79b, and VIM) out of 24 tested by PCR. The prevalence of B-cell restricted genes (CD19, CD20, and CD79b) suggests that this uniform population may be the clonal initiating (malignant) cells of Hodgkin lymphoma, despite their not showing translation to their respective proteins by immunohistochemical analysis. This is believed to be the first report of in-vivo cell-cell fusion of human lymphoma and rodent host cells, and may be a method to disclose genes regulating both organoid and metastasis signatures, suggesting that the horizontal transfer of tumor DNA to adjacent stromal cells may be implicated in tumor heterogeneity and progression. The B-cell gene signature of the hybrid xenografts suggests that Hodgkin lymphoma, or its initiating cells, is a B-cell malignancy.

Goldenberg, David M.; Gold, David V.; Loo, Meiyu; Liu, Donglin; Chang, Chien-Hsing; Jaffe, Elaine S.

2013-01-01

291

EGFR antisense RNA blocks expression of the epidermal growth factor receptor and partially reverse the malignant phenotype of human breast cancer MDA-MB-231 cells  

Microsoft Academic Search

The effects of human EGFR to the malignant phenotype of human breast cancer cell line MDA-MB-231 were investigated experimentally. A retroviral vector containing a 5'1350bp fragment of the human EGFR cDNA in the antisense orientation was transfected into targeted cells by lipofectamine. The effects on cell proliferation, cell cycle and adherent ability to extracellular matrix (ECM) components were studied after

Wen Hong Fan; Ying Lin Lu; Fan Deng; Xue Ming Ge; Shuang Liu; Pie-Hesin Tang; Pei-Hesin Tang

1998-01-01

292

Analysis of the colonization of unirradiated and irradiated SCID mice by human lymphoma and non-malignant lymphoid cells.  

PubMed

We have evaluated the severe combined immunodeficient (SCID) mouse as an in-vivo model for the study of non-Hodgkin's lymphomas (NHL). Characterization of the immune system of the animals in our SCID mouse colony was carried out to assess the numbers of lymphoid cells present, to determine natural killer (NK) cell activity as a function of age and to examine the histology of the lymphoid organs. In this study four human NHL established cell lines (Daudi, Namalwa, U937, MC116), lymphoma cells from four fresh NHL biopsies and normal peripheral blood mononuclear cells (PBMC) and bone marrow cells were investigated, after intraperitoneal injection into the mice. The presence of the human NHL cells in the peritoneum and spleen was assessed by FACS analysis. The colonization potential was investigated in a range of tissues by polymerase chain reaction (PCR) amplification of human repetitive sequences. These studies revealed clear differences in the abilities of the NHL cell types to colonize the SCID mice. Namalwa, Daudi and U937 cells demonstrated the highest efficiency of colonization and readily formed tumours, whereas MC116, the NHL biopsy cell populations and the non-malignant lymphoid cells showed little ability to survive and colonize other tissues in the SCID mice. Whole body irradiation of the SCID mice appeared to improve the survival of human PBMC, NHL biopsy cells and MC116 cells in the peritoneum, but had little effect on their colonization potential. The significance of these studies is discussed. PMID:8882960

Zubair, A C; Ali, S A; Rees, R C; Goepel, J R; Winfield, D A; Goyns, M H

1996-08-01

293

LIM Mineralization Protein-1 Inhibits the Malignant Phenotypes of Human Osteosarcoma Cells  

PubMed Central

Osteosarcoma (OS), also known as osteogenic sarcoma, is the most common primary malignancy of bone tumor in children and adolescents. However, its underlying molecular pathogenesis is still only vaguely understood. Recently, LIM mineralization protein-1 (LMP-1) was reported to be an essential positive regulator of osteoblast differentiation. In the present study, we found that the expression of LMP-1 is downregulated in OS tissues compared with adjacent normal tissues. Moreover, we restored the expression of LMP-1 through a recombinant adenovirus. Overexpression of LMP-1 inhibited cell proliferation and invasion, arrested cell cycle progression, and induced apoptosis in vitro. Finally, ectopic LMP-1 expression suppressed the expression of Runx2 and BMP-2 in OS cells. These data demonstrate that LMP-1 is an essential tumor suppressor in the OS pathological process, which will provide a new opportunity for discovering and identifying novel effective treatment strategies.

Liu, Huiwen; Huang, Lu; Zhang, Zhongzu; Zhang, Zhanming; Yu, Zhiming; Chen, Xiang; Chen, Zhuo; Zen, Yongping; Yang, Dong; Han, Zhimin; Shu, Yong; Dai, Min; Cao, Kai

2014-01-01

294

Multipotent Cancer Stem Cells Derived from Human Malignant Peritoneal Mesothelioma Promote Tumorigenesis  

PubMed Central

During the progression of malignant peritoneal mesothelioma (MPeM), tumor nodules propagate diffusely within the abdomen and tumors are characterized by distinct phenotypic sub-types. Recent studies in solid organ cancers have shown that cancer stem cells (CSCs) play a pivotal role in the initiation and progression of tumors. However, it is not known whether tumorigenic stem cells exist and whether they promote tumor growth in MPeM. In this study, we developed and characterized a CSC model for MPeM using stably expandable tumorigenic stem cells derived from patient tumors. We found morphologically distinct populations of CSCs that divide asymmetrically or symmetrically in MPeM in vitro cell culture. The MPeM stem cells (MPeMSCs) express stem cell markers c-MYC, NES and VEGFR2 and in the presence of matrix components cells form colony spheres. MPeMSCs are multipotent, differentiate into neuronal, vascular and adipose progeny upon defined induction and the differentiating cells express lineage-specific markers such as TUBB3, an early neuronal marker; vWF, VEGFA, VEGFC and IL-8, endothelial markers; and PPAR? and FABP4, adipose markers. Xenotransplantation experiments using MPeMSCs demonstrated early tumor growth compared with parental cells. Limiting dilution experiments using MPeMSCs and endothelial lineage-induced cells derived from a single MPeMSC resulted in early tumor growth in the latter group indicating that endothelial differentiation of MPeMSCs is important for MPeM tumor initiation. Our observation that the MPeM tumors contain stem cells with tumorigenic potential has important implications for understanding the cells of origin and tumor progression in MPeM and hence targeting CSCs may be a useful strategy to inhibit malignant progression.

Varghese, Sheelu; Whipple, Rebecca; Martin, Stuart S.; Alexander, H. Richard

2012-01-01

295

Inhibition of transient receptor potential canonical channels impairs cytokinesis in human malignant gliomas  

PubMed Central

Objectives Glial-derived primary brain tumours, gliomas, are among the fastest growing malignancies and present a huge clinical challenge. Research suggests an important, yet poorly understood, role of ion channels in growth control of normal and malignant cells. In this study, we sought to functionally characterize Transient Receptor Potential Canoncial (TRPC) channels in glioma cell proliferation. TRPC channels form non-selective cation channels that have been suggested to represent a Ca2+ influx pathway impacting cellular growth. Materials and Methods Employing a combination of molecular, biochemical and biophysical techniques, we characterized TRPC channels in glioma cells. Results We showed consistent expression of four channel family members (TRPC-1, -3, -5, -6) in glioma cell lines and acute patient-derived tissues. These channels gave rise to small, non-voltage-dependent cation currents that were blocked by the TRPC inhibitors GdCl3, 2-APB, or SKF96365. Importantly, TRPC channels contributed to the resting conductance of glioma cells and their acute pharmacological inhibition caused an ~10 mV hyperpolarization of the cells’ resting potential. Additionally, chronic application of the TRPC inhibitor SKF96365 caused near complete growth arrest. A detailed analysis, by fluorescence-activated cell sorting and time-lapse microscopy, showed that growth inhibition occurred at the G2 + M phase of the cell cycle with cytokinesis defects. Cells underwent incomplete cell divisions and became multinucleate, enlarged cells. Conclusions Nuclear atypia and enlarged cells are histopathological hallmarks for glioblastoma multiforme, the highest grade glioma, suggesting that a defect in TRPC channel function may contribute to cellular abnormalities in these tumours.

Bomben, V. C.; Sontheimer, H. W.

2009-01-01

296

Identification of cancer stem cell markers in human malignant mesothelioma cells  

SciTech Connect

Research highlights: {yields} We performed serial transplantation of surgical samples and established new cell lines of malignant mesothelioma. {yields} SP cell and expressions of CD9/CD24/CD26 were often observed in mesothelioma cell lines. {yields} SP and CD24{sup +} cells proliferated by asymmetric cell division-like manner. CD9{sup +} and CD24{sup +} cells have higher potential to generate spheroid colony. {yields} The marker-positive cells have clear tendency to generate larger tumors in mice. -- Abstract: Malignant mesothelioma (MM) is an aggressive and therapy-resistant neoplasm arising from the pleural mesothelial cells and usually associated with long-term asbestos exposure. Recent studies suggest that tumors contain cancer stem cells (CSCs) and their stem cell characteristics are thought to confer therapy-resistance. However, whether MM cell has any stem cell characteristics is not known. To understand the molecular basis of MM, we first performed serial transplantation of surgical samples into NOD/SCID mice and established new cell lines. Next, we performed marker analysis of the MM cell lines and found that many of them contain SP cells and expressed several putative CSC markers such as CD9, CD24, and CD26. Interestingly, expression of CD26 closely correlated with that of CD24 in some cases. Sorting and culture assay revealed that SP and CD24{sup +} cells proliferated by asymmetric cell division-like manner. In addition, CD9{sup +} and CD24{sup +} cells have higher potential to generate spheroid colony than negative cells in the stem cell medium. Moreover, these marker-positive cells have clear tendency to generate larger tumors in mouse transplantation assay. Taken together, our data suggest that SP, CD9, CD24, and CD26 are CSC markers of MM and could be used as novel therapeutic targets.

Ghani, Farhana Ishrat; Yamazaki, Hiroto; Iwata, Satoshi; Okamoto, Toshihiro [Division of Clinical Immunology, Institute of Medical Science, University of Tokyo, Tokyo (Japan)] [Division of Clinical Immunology, Institute of Medical Science, University of Tokyo, Tokyo (Japan); Aoe, Keisuke; Okabe, Kazunori; Mimura, Yusuke [Departments of Medical Oncology, Yamaguchi-Ube Medical Center, Yamaguchi (Japan)] [Departments of Medical Oncology, Yamaguchi-Ube Medical Center, Yamaguchi (Japan); Fujimoto, Nobukazu; Kishimoto, Takumi [Department of Respiratory Medicine, Okayama Rosai Hospital, Okayama (Japan)] [Department of Respiratory Medicine, Okayama Rosai Hospital, Okayama (Japan); Yamada, Taketo [Department of Pathology, Keio University School of Medicine, Tokyo (Japan)] [Department of Pathology, Keio University School of Medicine, Tokyo (Japan); Xu, C. Wilson [Drug Development Program, Nevada Cancer Institute, Las Vegas, NV (United States)] [Drug Development Program, Nevada Cancer Institute, Las Vegas, NV (United States); Morimoto, Chikao, E-mail: morimoto@ims.u-tokyo.ac.jp [Division of Clinical Immunology, Institute of Medical Science, University of Tokyo, Tokyo (Japan) [Division of Clinical Immunology, Institute of Medical Science, University of Tokyo, Tokyo (Japan); Drug Development Program, Nevada Cancer Institute, Las Vegas, NV (United States)

2011-01-14

297

First-in-Human Phase 0 Trial of Oral 5-iodo-2-pyrimidinone-2?-deoxyribose (IPdR) in Patients with Advanced Malignancies  

PubMed Central

Purpose Iododeoxyuridine (IdUrd), a halogenated nucleoside analog, produced clinical responses when administered as a radiosensitizer via continuous intravenous (c.i.v.) infusion over the course of radiation therapy. We conducted a Phase 0 trial of 5-iodo-2-pyrimidinone-2?-deoxyribose (IPdR), an oral prodrug of IdUrd, in patients with advanced malignances to assess whether the oral route was a feasible alternative to c.i.v. infusion prior to embarking on large-scale clinical trials. Plasma concentrations of IPdR, IdUrd, and other metabolites were measured after a single oral dose of IPdR. Patients and Methods Eligible patients had advanced refractory malignancies. A single oral dose of IPdR was administered per patient and patients were followed for 14 days for safety assessments; dose escalations were planned (150, 300, 600, 1200, and 2400 mg) with one patient per dose level (DL) and 6 patients at the highest DL. Blood sampling was performed over a 24-hour period for pharmacokinetic analysis. Results There were no drug-related adverse events. Plasma concentrations of IdUrd generally increased as the dose of IPdR escalated from 150 to 2400 mg. All patients at the 2400 mg dose achieved peak IdUrd levels of (mean ± SD) 4.0 ?M ± 1.02 ?M (25% CV) at 1.67 ± 1.21 hours after IPdR administration. Conclusions Adequate plasma levels of IdUrd were obtained to justify proceeding with a Phase I trial of IPdR in combination with radiation. This trial demonstrates the ability of a small, Phase 0 study to provide critical information for decision-making regarding future development of a drug.

Kummar, Shivaani; Anderson, Larry; Hill, Kimberly; Majerova, Eva; Allen, Deborah; Horneffer, Yvonne; Ivy, S. Percy; Rubinstein, Larry; Harris, Pamela; Doroshow, James H.; Collins, Jerry M.

2013-01-01

298

Gemcitabine uptake in glioblastoma multiforme: potential as a radiosensitizer.  

PubMed

Glioblastoma multiforme (GBM), the most frequent malignant brain tumor, has a poor prognosis, but is relatively sensitive to radiation. Both gemcitabine and its metabolite difluorodeoxyuridine (dFdU) are potent radiosensitizers. The aim of this phase 0 study was to investigate whether gemcitabine passes the blood-tumor barrier, and is phosphorylated in the tumor by deoxycytidine kinase (dCK) to gemcitabine nucleotides in order to enable radiosensitization, and whether it is deaminated by deoxycytidine deaminase (dCDA) to dFdU. Gemcitabine was administered at 500 or 1000 mg/m(2) just before surgery to 10 GBM patients, who were biopsied after 1-4 h. Plasma gemcitabine and dFdU levels varied between 0.9 and 9.2 microM and 24.9 and 72.6 microM, respectively. Tumor gemcitabine and dFdU levels varied from 60 to 3580 pmol/g tissue and from 29 to 72 nmol/g tissue, respectively. The gene expression of dCK (beta-actin ratio) varied between 0.44 and 2.56. The dCK and dCDA activities varied from 1.06 to 2.32 nmol/h/mg protein and from 1.51 to 5.50 nmol/h/mg protein, respectively. These enzyme levels were sufficient to enable gemcitabine phosphorylation, leading to 130-3083 pmol gemcitabine nucleotides/g tissue. These data demonstrate for the first time that gemcitabine passes the blood-tumor barrier in GBM patients. In tumor samples, both gemcitabine and dFdU concentrations are high enough to enable radiosensitization, which warrants clinical studies using gemcitabine in combination with radiation. PMID:18701427

Sigmond, J; Honeywell, R J; Postma, T J; Dirven, C M F; de Lange, S M; van der Born, K; Laan, A C; Baayen, J C A; Van Groeningen, C J; Bergman, A M; Giaccone, G; Peters, G J

2009-01-01

299

L1CAM promotes enrichment of immunosuppressive T cells in human pancreatic cancer correlating with malignant progression.  

PubMed

Regulatory T cell (T-reg) enrichment in the tumor microenvironment is regarded as an important mechanism of tumor immune escape. Hence, the presence of T-regs in highly malignant pancreatic ductal adenocarcinoma (PDAC) is correlated with short survival. Likewise, the adhesion molecule L1CAM is upregulated during PDAC progression in the pancreatic ductal epithelium also being associated with poor prognosis. To investigate whether L1CAM contributes to enrichment of T-regs in PDAC, human CD4(+)CD25(+)CD127(-)CD49d(-) T-regs and CD4(+)CD25(-) T-effector cells (T-effs) were isolated by magnetic bead separation from blood of healthy donors. Their phenotype and functional behavior were analyzed in dependence on human premalignant (H6c7) or malignant (Panc1) pancreatic ductal epithelial cells, either exhibiting or lacking L1CAM expression. T cells derived from blood and tumors of PDAC patients were analyzed by flow cytometry and findings were correlated with clinical parameters. Predominantly T-regs but not T-effs showed an increased migration on L1CAM expressing H6c7 and Panc1 cells. Whereas proliferation of T-regs did not change in the presence of L1CAM, T-effs proliferated less, exhibited a decreased CD25 expression and an increased expression of CD69. Moreover, these T-effs exhibited a regulatory phenotype as they inhibited proliferation of autologous T cells. Accordingly, CD4(+)CD25(-)CD69(+) T cells were highly abundant in PDAC tissues compared to blood being associated with nodal invasion and higher grading in PDAC patients. Overall, these data point to an important role of L1CAM in the enrichment of immunosuppressive T cells in particular of a CD4(+)CD25(-)CD69(+)-phenotype in PDAC providing a novel mechanism of tumor immune escape which contributes to tumor progression. PMID:24746181

Grage-Griebenow, Evelin; Jerg, Elfi; Gorys, Artur; Wicklein, Daniel; Wesch, Daniela; Freitag-Wolf, Sandra; Goebel, Lisa; Vogel, Ilka; Becker, Thomas; Ebsen, Michael; Röcken, Christoph; Altevogt, Peter; Schumacher, Udo; Schäfer, Heiner; Sebens, Susanne

2014-07-01

300

Targeted DNA vaccines eliciting crossreactive anti-idiotypic antibody responses against human B cell malignancies in mice  

PubMed Central

Background Therapeutic idiotypic (Id) vaccination is an experimental treatment for selected B cell malignancies. A broader use of Id-based vaccination, however, is hampered by the complexity and costs due to the individualized production of protein vaccines. These limitations may be overcome by targeted DNA vaccines encoding stereotyped immunoglobulin V regions of B cell malignancies. We have here investigated whether such vaccines might elicit cross-reactive immune responses thus offering the possibility to immunize subsets of patients with the same vaccine. Methods Fusion vaccines targeting patient Id to mouse Major Histocompatibility Complex (MHC) class II molecules (chimeric mouse/human) or chemokine receptors (fully human) on antigen-presenting cells (APC) were genetically constructed for two Chronic Lymphocytic Leukemia (CLL) patients and one prototypic stereotyped B-cell receptor (BCR) commonly expressed by Hepatitis C Virus (HCV)-associated Non Hodgkin Lymphoma (NHL). The A20 murine B lymphoma cells were engineered to express prototypic HCV-associated B cell lymphoma BCR. Anti-Id antibody responses were studied against stereotyped and non-stereotyped BCRs on CLL patients’ cells as well as transfected A20 cells. Results DNA vaccination of mice with Id vaccines that target APC elicited increased amounts of antibodies specific for the patient’s Id as compared with non targeted control vaccines. Anti–Id antibodies cross-reacted between CLL cells with closely related BCR. A20 cells engineered to express patients’ V regions were not tumorigenic in mice, preventing tumor challenge experiments. Conclusions These findings provide experimental support for use of APC-targeted fusion Id DNA vaccines for the treatment of B cell lymphoma and CLL that express stereotyped BCRs.

2014-01-01

301

Microbial regulation of intestinal radiosensitivity  

PubMed Central

We describe a method for treating germ-free (GF) mice with ?-irradiation and transplanting them with normal or genetically manipulated bone marrow while maintaining their GF status. This approach revealed that GF mice are markedly resistant to lethal radiation enteritis. Furthermore, administering lethal doses of total body irradiation to GF mice produces markedly fewer apoptotic endothelial cells and lymphocytes in the mesenchymal cores of their small intestinal villi, compared with conventionally raised animals that have acquired a microbiota from birth. Analysis of GF and conventionally raised Rag1-/- mice disclosed that mature lymphocytes are not required for the development of lethal radiation enteritis or the microbiota-associated enhancement of endothelial radiosensitivity. Studies of gnotobiotic knockout mice that lack fasting-induced adipose factor (Fiaf), a fibrinogen/angiopoietin-like protein normally secreted from the small intestinal villus epithelium and suppressed by the microbiota, showed that Fiaf deficiency results in loss of resistance of villus endothelial and lymphocyte populations to radiation-induced apoptosis. Together, these findings provide insights about the cellular and molecular targets involved in microbial regulation of intestinal radiosensitivity.

Crawford, Peter A.; Gordon, Jeffrey I.

2005-01-01

302

Radiosensitization Effect of STI-571 on Pancreatic Cancer Cells In Vitro  

SciTech Connect

Purpose: To examine STI-571-induced radiosensitivity in human pancreatic cancer cells in vitro. Methods and Materials: Three human pancreatic cancer cell lines (Bxpc-3, Capan-1, and MiaPaCa-2) exhibiting different expression levels of c-Kit and platelet-derived growth factor receptor beta (PDGFRbeta) and showing different K-ras mutation types were used. For evaluation of the antitumor activity of STI-571 in combination with radiation, clonogenic survival assays, Western blot analysis, and the annexin V/propidium iodide assay with microscopic evaluation by 4',6-diamidino-2-phenylindole were conducted. Results: Dramatic phosphorylated (p)-c-Kit and p-PDGFRbeta attenuation, a modest dose- and time-dependent growth inhibition, and significant radiosensitization were observed after STI-571 treatment in view of apoptosis, although the levels of growth inhibition and increased radiosensitization were different according to cell lines. The grades of radiosensitivity corresponded to the attenuation levels of p-c-Kit and p-PDGFRbeta by STI-571, particularly to those of p-c-Kit, and the radiosensitivity was partially affected by K-ras mutation in pancreatic cancer cells. Among downstream pathways associated with c-Kit or PDGFRbeta, p-PLCgamma was more closely related to radiosensitivity compared with p-Akt1 or p-extracellular signal-regulated kinase 1. Conclusion: STI-571 enhances radiation response in pancreatic cancer cells. This effect is affected by the attenuation levels of p-c-Kit or p-PDGFRbeta, and K-ras mutation status. Among them, p-c-Kit plays more important roles in the radiosensitivity in pancreatic cancer compared with p-PDGFRbeta or K-ras mutation status.

Chung, Hye Won [Division of Gastroenterology, Department of Internal Medicine, Yonsei University College of Medicine, Seoul (Korea, Republic of); Wen, Jing [Brain Korea 21 Project for Medical Sciences, Yonsei University College of Medicine, Seoul (Korea, Republic of); Lim, Jong-Baeck [Department of Laboratory Medicine, Yonsei University College of Medicine, Seoul (Korea, Republic of); Bang, Seung Min; Park, Seung Woo [Division of Gastroenterology, Department of Internal Medicine, Yonsei University College of Medicine, Seoul (Korea, Republic of); Song, Si Young, E-mail: sysong@yuhs.a [Division of Gastroenterology, Department of Internal Medicine, Yonsei University College of Medicine, Seoul (Korea, Republic of); Brain Korea 21 Project for Medical Sciences, Yonsei University College of Medicine, Seoul (Korea, Republic of)

2009-11-01

303

Malignant hyperthermia.  

PubMed

Malignant hyperthermia refers to covert myopathies, which do not affect the individual during daily life activities, but may lead to life-threatening tachycardia, rigor, labile blood pressure and most importantly high-grade temperature when exposed to general anaesthesia. This conditions is mimicked by thyroid storm, neuroleptic malignant syndrome, phaeochromocytoma and sepsis. We present a presumptive case of malignant hyperthermia. PMID:14764260

Nasir, Khawaja Kamal; Zafar, Ayaz-bin; Mansoor, Faraz; Mushtaq, Sadia; Ahmad, Jawad; Khan, Imran Muhammad

2004-01-01

304

Variation in Susceptibility of Human Malignant Melanomas to Oncolytic Vesicular Stomatitis Virus  

PubMed Central

Background Vesicular stomatitis virus (VSV) is a novel, anti-cancer therapy that selectively targets cancer cells with defective antiviral responses; however, not all malignant cells are sensitive to the oncolytic effects of VSV. Herein, we explore the mechanistic determinants of mutant M protein VSV (M51R-VSV) susceptibility in malignant melanoma cells. Methods Cell viability after VSV infection was measured by the 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) viability assay in a panel of melanoma cell lines. VSV infectability, viral protein synthesis and viral progeny production were quantified by flow cytometry, 35S-methionine electrophoresis, and viral plaque assays, respectively. Interferon (IFN) responsiveness was determined using MTS assay after ?-IFN pre-treatment. Xenografts were established in athymic nude mice and treated with intratumoral M51R-VSV. Results Cell viability after M51R-VSV infection at a multiplicity of infection (MOI) of 10 pfu/mL, 48 hours post-infection) ranged between 0±1 and 59±9% (mean ± standard deviation). Sensitive cell lines supported VSV infection, viral protein synthesis, and viral progeny production. In addition, when pre-treated with ?-IFN, sensitive cells became resistant to M51R-VSV, suggesting that IFN-mediated antiviral signaling is defective in these cells. In contrast, resistant melanoma cells do not support VSV infection, viral protein synthesis, or viral replication, indicating that anti-viral defenses remain intact. In a murine xenograft model, intratumoral M51R-VSV treatment decreased tumor growth relative to controls after 26 days in SK-Mel 5 (?21±19% vs. 2100±770%, p<0.0001) and SK-Mel 3 (2000±810% vs 7000±3000%, p=0.008) established tumors. Conclusions M51R-VSV is a viable, anti-cancer therapy, but susceptibility varies among melanomas. Future work will exploit specific mechanisms of resistance to expand the therapeutic efficacy of M51R-VSV.

Blackham, Aaron U; Northrup, Scott A; Willingham, Mark; D'Agostino, Ralph B; Lyles, Douglas S; Stewart, John H

2012-01-01

305

Overexpression of Karyopherin 2 in Human Ovarian Malignant Germ Cell Tumor Correlates with Poor Prognosis  

PubMed Central

Background The aim of this study was to identify a biomarker useful in the diagnosis and therapy of ovarian malignant germ cell tumor (OMGCT). Methods The karyopherin 2 (KPNA2) expression in OMGCT and normal ovarian tissue was determined by standard gene microarray assays, and further validated by a quantitative RT-PCR and immunohistochemistry. The correlation between KPNA2 expression in OMGCT and certain clinicopathological features were analyzed. Expression of SALL4, a stem cell marker, was also examined in comparison with KPNA2. Results KPNA2 was found to be over-expressed by approximately eight-fold in yolk sac tumors and immature teratomas compared to normal ovarian tissue by microarray assays. Overexpression was detected in yolk sac tumors, immature teratomas, dysgerminomas, embryonal carcinomas, mature teratomas with malignant transformation and mixed ovarian germ cell tumors at both the transcription and translation levels. A positive correlation between KPNA2 and SALL4 expression at both the transcription level (R?=?0.5120, P?=?0.0125), and the translation level (R?=?0.6636, P<0.0001), was presented. Extensive expression of KPNA2 was positively associated with pathologic type, recurrence and uncontrolled, ascitic fluid presence, suboptimal cytoreductive surgery necessity, resistance/refraction to initial chemotherapy, HCG level and SALL4 level in OMGCT patients. KPNA2 was found to be an independent factor for 5-year disease-free survival (DFS) of OMGCT (P?=?0.02). The 5-year overall survival (OS) and DFS rate for KPNA2-low expression patients (88% and 79%, n?=?48) were significantly higher than the OS and DFS rate for KPNA2-high expression patients (69% and 57.1%, n?=?42)(P?=?0.0151, P?=?0.0109, respectively). The 5-year OS and DFS rate for SALL4-low expression patients (84% and 74%, n?=?62) was marginally significantly higher than the high expression patients (78.6% and 71.4%, n?=?28)(P?=?0.0519, P?=?0.0647, respectively). Conclusions KPNA2 is a potential candidate molecular marker and important prognostic marker in OMGCT patients.

Wang, Jian-Hua; Zhou, Yun; Li, Li; Yu, Yan-Hong; Huang, Long; Jia, Wei-Hua; Zeng, Musheng; Yun, Jing-Ping; Luo, Rong-Zhen; Zheng, Min

2012-01-01

306

Zingipain, A cysteine protease from Zingiber ottensii Valeton rhizomes with antiproliferative activities against fungi and human malignant cell lines.  

PubMed

The objective of this study was to investigate the activity of a protein identified as cysteine protease, purified from Zingiber ottensii Valeton rhizomes, in terms of antiproliferation against fungi, bacteria, and human malignant cell lines. By means of buffer extraction followed by (NH(4))(2)SO(4) precipitation and ion-exchange chromatography, the obtained dominant protein (designated F50) was submitted to non-denaturing and reducing sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), where a single band and three bands were revealed from eletrophoretic patterns, respectively. It could be concluded at this point that the F50 was potentially a heterotrimer or heterodimer composed of either two small (?13.8 and ?15.2 kD) subunits or these two together with a larger (?32.5 kD) one. In-gel digestion was carried out for the most intense band from reducing SDS-PAGE, and to the resulting material was applied liquid chromatography (LC)-mass spectroscopy (MS)/MS. The main F50 subunit was found to contain fragments with 100% similarity to zingipain-1, a cysteine protease first discovered in Zingiber officinale. The activity corresponding to the identified data, cysteine protease, was then confirmed in the F50 by azocasein assay and a positive result was obtained. The F50 then was further investigated for antiproliferation against three plant pathogenic fungi species by disk diffusion test, four bacterial species by direct exposure in liquid culture and dish diffusion tests, and five human malignant cell lines by tissue culture assay. It was found that a dose of 23.6 µg F50/0.3 cm(2) of paper disk exhibited the best inhibitory effect against Collectotrichum cassiicola, while lesser effects were found in Exserohilum turicicum and Fusarium oxysporum, respectively. No inhibitory effect against bacterial proliferation was detected in all studied bacterial strains. However, relatively strong antiproliferative effects were found against five human cell lines, with IC50 values ranging from 1.13 µg/mL (hepatoma cancer; HEP-G2) to 5.37 µg/mL (colon cancer; SW620). By periodic acid-Schiff's staining and phenol-sulfuric acid assay, the F50 was determined as a glycoprotein containing 26.30 ± 1.01% (by weight) of carbohydrate. Thus, a new glycoprotein with protease activity was successfully identified in Zingiber ottensii rhizome. The glycoprotein also contained antiproliferative activity against some plant pathogenic fungi and human cancer cell lines. PMID:21442550

Karnchanatat, Aphichart; Tiengburanatam, Nathachai; Boonmee, Apaporn; Puthong, Songchan; Sangvanich, Polkit

2011-01-01

307

Detection of mRNA of sodium iodide symporter in benign and malignant human thyroid tissues  

Microsoft Academic Search

Human sodium iodide symporter (hNIS) is an intrinsic membrane protein with 12 transmembrane regions, which shows homology to other sodium-dependent transporters. There is controversy as to the amount of hNIS expression in different kinds of human thyroid cancer tissues and cell lines. In this study, reverse transcription-polymerase chain reaction (RT-PCR) was used to detect mRNA of hNIS in various fresh

Miaw-Jene Liou; Jen-Der Lin; Err-Cheng Chan; Feng-Hsuan Liu; Tzu-Chieh Chao; Hsiao-Fen Weng

2000-01-01

308

Ataxia-telangiectasia mutated and the Mre11-Rad50-NBS1 complex: promising targets for radiosensitization.  

PubMed

Radiotherapy plays a central part in cancer treatment, and use of radiosensitizing agents can greatly enhance this modality. Although studies have shown that several chemotherapeutic agents have the potential to increase the radiosensitivity of tumor cells, investigators have also studied a number of molecularly targeted agents as radiosensitizers in clinical trials based on reasonably promising preclinical data. Recent intense research into the DNA damage-signaling pathway revealed that ataxia-telangiectasia mutated (ATM) and the Mre11-Rad50-NBS1 (MRN) complex play central roles in DNA repair and cell cycle checkpoints and that these molecules are promising targets for radiosensitization. Researchers recently developed three ATM inhibitors (KU-55933, CGK733, and CP466722) and an MRN complex inhibitor (mirin) and showed that they have great potential as radiosensitizers of tumors in preclinical studies. Additionally, we showed that a telomerase-dependent oncolytic adenovirus that we developed (OBP-301 [telomelysin]) produces profound radiosensitizing effects by inhibiting the MRN complex via the adenoviral E1B55kDa protein. A recent Phase I trial in the United States determined that telomelysin was safe and well tolerated in humans, and this agent is about to be tested in combination with radiotherapy in a clinical trial based on intriguing preclinical data demonstrating that telomelysin and ionizing radiation can potentiate each other. In this review, we highlight the great potential of ATM and MRN complex inhibitors, including telomelysin, as radiosensitizing agents. PMID:22525466

Kuroda, Shinji; Urata, Yasuo; Fujiwara, Toshiyoshi

2012-01-01

309

Transient receptor potential canonical channels are essential for chemotactic migration of human malignant gliomas.  

PubMed

The majority of malignant primary brain tumors are gliomas, derived from glial cells. Grade IV gliomas, Glioblastoma multiforme, are extremely invasive and the clinical prognosis for patients is dismal. Gliomas utilize a number of proteins and pathways to infiltrate the brain parenchyma including ion channels and calcium signaling pathways. In this study, we investigated the localization and functional relevance of transient receptor potential canonical (TRPC) channels in glioma migration. We show that gliomas are attracted in a chemotactic manner to epidermal growth factor (EGF). Stimulation with EGF results in TRPC1 channel localization to the leading edge of migrating D54MG glioma cells. Additionally, TRPC1 channels co-localize with the lipid raft proteins, caveolin-1 and ?-cholera toxin, and biochemical assays show TRPC1 in the caveolar raft fraction of the membrane. Chemotaxis toward EGF was lost when TRPC channels were pharmacologically inhibited or by shRNA knockdown of TRPC1 channels, yet without affecting unstimulated cell motility. Moreover, lipid raft integrity was required for gliomas chemotaxis. Disruption of lipid rafts not only impaired chemotaxis but also impaired TRPC currents in whole cell recordings and decreased store-operated calcium entry as revealed by ratiomeric calcium imaging. These data indicated that TRPC1 channel association with lipid rafts is essential for glioma chemotaxis in response to stimuli, such as EGF. PMID:21506118

Bomben, Valerie C; Turner, Kathryn L; Barclay, Tia-Tabitha C; Sontheimer, Harald

2011-07-01

310

Transient Receptor Potential Canonical Channels Are Essential for Chemotactic Migration of Human Malignant Gliomas  

PubMed Central

The majority of malignant primary brain tumors are gliomas, derived from glial cells. Grade IV gliomas, Glioblastoma multiforme, are extremely invasive and the clinical prognosis for patients is dismal. Gliomas utilize a number of proteins and pathways to infiltrate the brain parenchyma including ion channels and calcium signaling pathways. In this study, we investigated the localization and functional relevance of transient receptor potential canonical (TRPC) channels in glioma migration. We show that gliomas are attracted in a chemotactic manner to epidermal growth factor (EGF). Stimulation with EGF results in TRPC1 channel localization to the leading edge of migrating D54MG glioma cells. Additionally, TRPC1 channels co-localize with the lipid raft proteins, caveolin-1 and ?-cholera toxin, and biochemical assays show TRPC1 in the caveolar raft fraction of the membrane. Chemotaxis toward EGF was lost when TRPC channels were pharmacologically inhibited or by shRNA knockdown of TRPC1 channels, yet without affecting unstimulated cell motility. Moreover, lipid raft integrity was required for gliomas chemotaxis. Disruption of lipid rafts not only impaired chemotaxis but also impaired TRPC currents in whole cell recordings and decreased store-operated calcium entry as revealed by ratiomeric calcium imaging. These data indicated that TRPC1 channel association with lipid rafts is essential for glioma chemotaxis in response to stimuli, such as EGF.

Bomben, Valerie C.; Turner, Kathryn L.; Barclay, Tia-tabitha C.; Sontheimer, Harald

2013-01-01

311

RNA interference against SPARC promotes the growth of U-87MG human malignant glioma cells  

PubMed Central

Malignant glioma is a highly invasive brain tumor resistant to conventional therapies. Secreted protein acidic and rich in cysteine (SPARC) has been shown to facilitate glioma invasion. However, the effects of SPARC on cell growth have yet to be adequately elucidated. In this study, we constructed a plasmid expressing shRNA against SPARC, evaluated the effect of SPARCshRNA on SPARC expression and then assessed its effect on cell growth in U-87MG cells. Using plasmid-delivered shRNA, we effectively suppressed SPARC expression in U-87MG cells. Cell growth curves and colony formation assay suggested that the introduction of SPARCshRNA resulted in an increase of cell growth and colony formation. We also showed that knockdown of SPARC expression was capable of promoting the cell cycle progression from the G1 to S phase. However, no difference was found in the level of apoptosis. A molecular analysis of signal mediators indicated that the inhibition of p-c-Raf (Ser259) and accumulation of p-GSK-3? (Ser9) and p-AKT (Ser473) may be connected with the growth promotion by SPARC shRNA. Our study may provide an insight into the biological function of SPARC in glioma.

Liu, Haiyan; Xu, Yuanyuan; Chen, Yun; Zhang, Haowen; Fan, Saijun; Feng, Shuang; Liu, Fenju

2011-01-01

312

Microwave-induced local hyperthermia in combination with radiotherapy of human malignant tumors  

SciTech Connect

Since 1976, two groups of patients have been treated with local microwave hyperthermia immediately following ionizing radiation. Group A patients had measurable multiple lesions assigned radiotherapy only, microwave hyperthermia only, or combined treatment. Ionizing radiation in 200 to 600 rad fractions was used 2 to 5 times per week to a total of 1800 to 4200 rad in 5 to 14 fractions. Group B patients had combination treatment only, with radiation fractions of 200 to 600 rad 2 to 5 times per week to a total of 200 to 4800 rad total in 6 to 20 fractions. Both groups received hyperthermia (42 to 44 C) 2 to 3 times per week, maximum ten sessions in four weeks. The 19 patients treated have had squamous cell carcinoma, adenocarcinoma, malignant melanoma, plasmacytoma, epithelioid sarcoma, and undifferentiated carcinoma. After more than 150 hyperthermia sessions, we find: (1) local hyperthermia with microwave alone or in combination with ionizing radiation can be used with excellent normal tissue tolerance provided local tissue temperatures are carefully monitored and controlled; (2) a higher level of heat induction in tumor tissue as compared to surrounding normal tissues; and (3) repeated hyperthermia at 42 to 43.5 C for 45 minutes per session immediately following photon irradiation yields a favorable therapeutic result, occasionally dramatic. Local microwave hyperthermia in combination withradiotherapy offers the possibility of substantial impact on clinical cancer therapy, whether of curative or palliative intent.

U, R.; Noell, K.T.; Woodward, K.T.; Worde, B.T.; Fishburn, R.I.; Miller, L.S.

1980-02-15

313

Cell proliferation in serial biopsies through human malignant brain tumours: measurement using Ki67 antibody labelling.  

PubMed

Cell proliferation was assessed in brain tumours using the monoclonal antibody Ki67 which recognizes a nuclear antigen expressed by proliferating cells. Using a novel stereotactic biopsy procedure, serial 1 cm biopsies were taken along a trajectory through six malignant brain tumours. Specimens were also obtained from 10 other brain tumours during conventional surgery. The percentage of Ki67 positive cells was determined as a fraction of the total number of tumour cells present. The Ki67 index for anaplastic astrocytomas and glioblastomas was significantly higher (Ki67 index range 11-18%) than that for benign or low grade tumours. Significant variation in proliferation was measured along the biopsy track through individual tumours (e.g. 0-12.3%) which correlated well with histological appearance. The Ki67 indices of normal brain were very low. In general the Ki67 indices increased with increasing histological grade and also appear to be a useful indicator of the active tumour volume and margin. This method provides spatial information about tumour proliferation which may be used to decide between different treatments and relate to prognosis. PMID:1892572

Parkins, C S; Darling, J L; Gill, S S; Revesz, T; Thomas, D G

1991-01-01

314

The role of CXCR4 in highly malignant human gliomas biology: Current knowledge and future directions.  

PubMed

Given the extensive histomorphological heterogeneity of high-grade gliomas, in terms of extent of invasiveness, angiogenesis, and necrosis and the poor prognosis for patients despite the advancements made in therapeutic management. The identification of genes associated with these phenotypes will permit a better definition of glioma heterogeneity, which may ultimately lead to better treatment strategies. CXCR4, a cell surface chemokine receptor, is implicated in the growth, invasion, angiogenesis and metastasis in a wide range of malignant tumors, including gliomas. It is overexpressed in glioma cells according to tumor grade and in glioma tumor initiating cells. There have been various reports suggesting that CXCR4 is required for tumor proliferation, invasion, angiogenesis, and modulation of the immune response. It may also serve as a prognostic factor in characterizing subsets of glioblastoma multiforme, as patients with CXCR4-positive gliomas seem to have poorer prognosis after surgery. Aim of this review was to analyze the current literature on biological effects of CXCR4 activity and its role in glioma pathogenesis. A better understanding of CXCR4 pathway in glioma will lead to further investigation of CXCR4 as a novel putative therapeutic target. GLIA 2014;62:1015-1023. PMID:24715652

Gagliardi, Filippo; Narayanan, Ashwin; Reni, Michele; Franzin, Alberto; Mazza, Elena; Boari, Nicola; Bailo, Michele; Zordan, Paola; Mortini, Pietro

2014-07-01

315

An in vitro inhibition of human malignant cell growth of crude water extract of cassava (Manihot esculenta Crantz) and commercial linamarin  

Microsoft Academic Search

Yusuf, U.F., Fakhru'l-Razi, A., Rosli, R., Iyuke, S.E., Billa, N., Abdullah, N. and Umar-Tsafe, N. An in vitro inhibition of human malignant cell growth of crude water extract of cassava (Manihot esculenta Crantz) and commercial linamarin

Umar F. Yusuf; Fakhru' l-Razi Ahmadun; Rozita Rosli; Sunny E. Iyuke; Nashiru Billa; Nasir Umar-Tsafe

316

Malignant transformation of immortalized human bronchial epithelial cells by asbestos fibers.  

PubMed Central

Although asbestos is a well-established lung carcinogen, there currently is no suitable human cell model in which to examine the underlying cellular and molecular changes associated with fiber-mediated bronchial carcinogenesis. Using a recently established transformation model based on a human papillomavirus-immortalized human bronchial epithelial cell line, we successfully transformed these BEP2D cells after a single, 7-day treatment with a 20-microgram/ml (4 micrograms per cm2 area) dose of Union Internationale Contre le Cancer (UICC) Rhodesian chrysotile fibers. Asbestos treatment resulted in a surviving fraction of 0.18 compared to control cells. Transformed cells developed through a series of sequential steps, including altered growth kinetics, resistance to serum-induced terminal differentiation, and anchorage-independent growth, before becoming tumorigenic to form progressively growing tumors in nude mice. Seven tumorigenic cell lines were isolated and determined to be of human epithelial origin based on immunofluorescent staining of keratin and isozyme analysis. Analysis of tumor DNA revealed no mutations at either codon 12 or 13 in any the ras oncogenes. An independent role for K-ras mutation in fiber carcinogenesis, therefore, cannot be confirmed. This model provides a unique opportunity to study the cellular and molecular changes at the various stages in fiber-mediated neoplastic transformation of human bronchial epithelial cells. Images Figure 3. Figure 4.

Hei, T K; Wu, L J; Piao, C Q

1997-01-01

317

Differential expression of laminin 5 (alpha 3 beta 3 gamma 2) by human malignant and normal prostate.  

PubMed Central

Laminin 5 is an extracellular matrix protein integral to the formation of the hemidesmosomes that attach normal basal cells to the underlying basal lamina. We have shown that these hemidesmosomal complexes are lost in prostate carcinoma, possibly allowing malignant cells to detach from the anchoring structures and then to invade and migrate through the adjacent tissue. Our previous immunohistochemical studies of normal and malignant human prostate tissue demonstrated that the laminin subchains alpha 1, alpha 2, beta 1, beta 2, gamma 1, and gamma 2 were all expressed as normal components of the basal lamina surrounding prostate glands. Although most of these subchains were also expressed by the de novo basal lamina synthesized by prostate carcinoma, the gamma 2 subchain of laminin 5 was not detected. In an effort to investigate the role laminin 5 plays in the tumorigenesis of prostate carcinoma, the protein expression of the three subchains of laminin 5 (alpha 3, beta 3, and gamma 2) was compared in normal prostate, prostatic intraepithelial neoplasia, and invasive carcinoma using immunohistochemistry. The results showed that the protein for the alpha 3 subchain of laminin 5 is retained by both normal prostate epithelium and prostate carcinoma, but the beta 3 and the gamma 2 subchains were not detected in invasive carcinoma. Despite the absence of the gamma 2 protein, however, the carcinoma cells continued to express substantial amounts of the gamma 2 mRNA. Although it is unclear how the gene for the gamma 2 subchain of laminin 5 is regulated, results of this study suggest that there is a post-transcriptional defect in the expression of the gamma 2 subchain that occurs during the progression from a premalignant lesion to invasive carcinoma. As laminin 5 is a component of the anchoring filaments, the failure to express the gamma 2 subchain may contribute to the failure to form anchoring filaments and hemidesmosomes. This failure of hemidesmosome formation results in a less stable epithelial-stromal junction, which may allow malignant cells more potential to invade and spread through adjacent structures. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5

Hao, J.; Yang, Y.; McDaniel, K. M.; Dalkin, B. L.; Cress, A. E.; Nagle, R. B.

1996-01-01

318

Role of androgen and vitamin D receptors in endothelial cells from benign and malignant human prostate  

PubMed Central

Forty years ago, Judah Folkman (Folkman. N Engl J Med 285: 1182–1186, 1971) proposed that tumor growth might be controlled by limiting formation of new blood vessels (angiogenesis) needed to supply a growing tumor with oxygen and nutrients. To this end, numerous “antiangiogenic” agents have been developed and tested for therapeutic efficacy in cancer patients, including prostate cancer (CaP) patients, with limited success. Despite the lack of clinical efficacy of lead anti-angiogenic therapeutics in CaP patients, recent published evidence continues to support the idea that prostate tumor vasculature provides a reasonable target for development of new therapeutics. Particularly relevant to antiangiogenic therapies targeted to the prostate is the observation that specific hormones can affect the survival and vascular function of prostate endothelial cells within normal and malignant prostate tissues. Here, we review the evidence demonstrating that both androgen(s) and vitamin D significantly impact the growth and survival of endothelial cells residing within prostate cancer and that systemic changes in circulating androgen or vitamin D drastically affect blood flow and vascularity of prostate tissue. Furthermore, recent evidence will be discussed about the expression of the receptors for both androgen and vitamin D in prostate endothelial cells that argues for direct effects of these hormone-activated receptors on the biology of endothelial cells. Based on this literature, we propose that prostate tumor vasculature represents an unexplored target for modulation of tumor growth. A better understanding of androgen and vitamin D effects on prostate endothelial cells will support development of more effective angiogenesis-targeting therapeutics for CaP patients.

Chung, Ivy; Montecinos, Viviana P.; Buttyan, Ralph; Johnson, Candace S.; Smith, Gary J.

2013-01-01

319

Human papillomavirus in malignant cervical lesions in Surinam, a high-risk country, compared to the Netherlands, a low-risk country  

Microsoft Academic Search

Krul EJT, van de Vijver MJ, Schuuring E, Van Kanten RW, Peters AAW, Fleuren GJ. Human papillomavirus in malignant cervical lesions in Surinam, a high-risk country, compared to the Netherlands, a low-risk country. Int J Gynecol Cancer 1999; 9: 206-211. In various countries epidemiologic studies show an association between human papillomavirus (HPV) and cancer of the uterine cervix. We de-

E. J. T. KRUL; M. J. VAN DE VIJVER; E. SCHUURING; R. W. VAN KANTEN; A. A. W. PETERS; G. J. FLEUREN

1999-01-01

320

Expression of vimentin filaments in canine malignant mammary gland tumors: A simulation of clinicopathological features of human breast cancer  

PubMed Central

Canine malignant mammary gland tumors (CMMGTs) are the most common malignancies observed in females. Several biological similarities have been reported between CMMGTs and human breast cancer (HBC). The present study aimed to assess the correlation of vimentin filaments overexpression, as part of the process of epithelial-mesenchymal transition (EMT) and the clinicopathological characteristics in CMMGTs. The clinicopathological characteristics of 42 CMMGTs were collected. Paraffin-embedded blocks underwent immunohistochemistry staining, which was performed using vimentin (to assess the evolution of the EMT process), Ki-67 (for evaluation of tumor proliferation) and cluster of differentiation 34 (CD34) (for evaluation of angiogenesis) antibodies. The tumor stage, grade, vascular invasion, margin status, rate of expression of the vimentin filaments, microvessel density-CD34 and proliferation rate data were obtained. Finally, the association between the expression of the vimentin filaments and those parameters was resolved statistically. A significant association was shown between the overexpression of the vimentin filaments and tumor size (r=0.71, P=0.03), tumor grade (r=0.80, P=0.021), angiogenesis (r=0.57, P=0.043), proliferation coefficient (r=0.06, P=0.001) and vascular invasion (r=0.76, P=0.043). Vimentin overexpression did not statistically correlate with the tumor stage or the margin status. Similar to the findings of the present study, certain recent studies have indicated that vimentin filament expression in HBC and CMMGTs is associated with the severity of cancer. Thus, spontaneous canine mammary tumor models appear to be an appropriate animal model for breast cancer research, and the results of the present study could aid to reinforce the association.

RISMANCHI, SANAZ; YADEGAR, ORLY; MUHAMMADNEJAD, SAMAD; AMANPOUR, SAEID; TAGHIZADEH-JAHED, MASOUD; MUHAMMADNEJAD, AHAD

2014-01-01

321

Loss of the malignant phenotype of human neuroblastoma cells by a catalytically inactive dominant-negative hTERT mutant.  

PubMed

Telomerase, a ribonucleoprotein complex mainly composed of the reverse transcriptase catalytic subunit (human telomerase reverse transcriptase, hTERT) and the RNA component (hTR), is a key enzyme of cancer progression. That aggressive stage 4-neuroblastoma expressed high levels of telomerase activity, whereas favorable tumors had no or little telomerase expression and activity, prompted us to investigate the role of this enzyme in this tumor model of altered proliferation, neuronal differentiation, and apoptosis. A human MYCN-amplified neuroblastoma cell line (IGR-N-91) was engineered to stably express either the normal hTERT protein (WT-hTERT) or a catalytically inactive dominant-negative mutant of this protein (DN-hTERT). We showed that DN-hTERT expression inhibited the endogenous hTERT in the malignant neuroblasts without telomere shortening nor loss of in vitro proliferative capacity. Importantly, DN-hTERT expression induced major changes in cell morphology of neuroblasts that switched them from a neuronal to a substrate adherent phenotype, which was more prone to apoptosis and lost their tumorigenic properties in nude mice. These biologic effects arose from modifications in the expression of genes involved in both apoptosis and neuroblastoma biology. Taken together these results highlighted the functional relevance of noncanonical functions of hTERT in the determination of neuroblast cell fate. Therefore, our results envision new therapeutic strategies for metastatic neuroblastoma therapeutic management. PMID:22933702

Samy, Mona; Gattolliat, Charles-Henry; Pendino, Frédéric; Hillion, Josette; Nguyen, Eric; Bombard, Sophie; Douc-Rasy, Sétha; Bénard, Jean; Ségal-Bendirdjian, Evelyne

2012-11-01

322

Upper and lower respiratory tract infections by human enterovirus and rhinovirus in adult patients with hematological malignancies.  

PubMed

The impact of human enterovirus (HEV) and human rhinovirus (HRV) respiratory tract infections in adult patients with hematological malignancies has been infrequently reported. We retrospectively studied 31 patients with an upper or lower respiratory tract infection (URTI/LRTI) by HEV (n = 18) or HRV (n = 15). At onset, a LRTI was present in 6 (33%) and 2 (13%) episodes of HEV and HRV infections, respectively, with or without an URTI. Progression to LRTI (pneumonia) from prior URTI was seen in 1 (6%) and 2 (13%) HEV and HRV infections, respectively. The presence of lymphocytopenia (<0.5 x 10(9)/l) was higher in LRTI by HEV: 4/5 (80%) versus 2/10 (20%) by HRV. Eight of 18 (44%) patients with immunosuppression versus 3/14 (21%) patients with no immunosuppression at the onset of respiratory infection developed a LRTI. Thirteen per cent of patients had associated respiratory infections from bacteria, aspergillus, or CMV. Pulmonary aspergillosis was diagnosed in 20% of HRV infections. Three of 11 patients (27%) with a LRTI died, but pulmonary copathogens were also involved in all cases. In conclusion, HEV and HRV can be associated with LRTI in immunocompromised patients, although their direct impact on mortality is uncertain. PMID:17563077

Parody, R; Rabella, N; Martino, R; Otegui, M; del Cuerpo, M; Coll, P; Sierra, J

2007-09-01

323

A rapid and simple assay for human blood malignancy engraftment, homing and chemotherapy treatment using fluorescent imaging of avian embryos.  

PubMed

Detection of grafted human cells in mice using fluorescence is a rapid and simple technique whose use is continually expanding. Robust engraftment of human hematological malignancy (HHM) lines and patient cells into the naturally immunodeficient turkey embryo has recently been demonstrated by polymerase chain reaction (PCR), fluorescence activated cell sorting (FACS) and histology. We demonstrate here that fluorescence imaging is a rapid and simple technique for detecting engraftment and homing of cells derived from HHM in turkey embryos. Raji lymphoma cells expressing a far-red fluorescent protein were injected intravascularly into turkey embryos and fluorescence was detected 8 days later in their limbs and skulls. Much stronger signals were obtained after removal of the bones from the limbs. Unlabeled Raji cells did not give a fluorescent signal. Treatment with doxorubicin dramatically reduced the fluorescent signal. Intravenously injected HL-60 leukemia cells labeled with infrared-fluorescing dye were detected in the bone marrow after 16 h. Homing was active, although some non-specific fluorescence was present. Use of fluorescence imaging of HHM in turkey embryos is therefore feasible and reduces the time, effort and expense for detecting engraftment. This technique has potential to become a high-throughput xenograft system for hematological chemotherapy development and testing, and for study of hematological cell homing. PMID:21895546

Grinberg, Igor; Dukhovny, Anna; Goldstein, Ronald S

2012-03-01

324

Internalization with high targeting potential of mouse monoclonal antibody ONS-M21 recognizing human malignant glioma antigen.  

PubMed

In order to evaluate the targeting potential of mouse monoclonal antibody ONS-M21 recognizing a human astrocytoma- and medulloblastoma-associated antigen, the internalization ability of this antibody and the selective cytotoxicity in the toxin-conjugated form were examined. Internalization assay with 125I-labeled ONS-M21 showed that about 20% of the total radioactivities was detected in the cellular fraction of human medulloblastoma cell line ONS-76 cells and that the reaction reached a plateau level in 30 min. To examine the selective delivery capacity of a high molecular substance in place of 125I, an immunotoxin was prepared with ricin A chain and ONS-M21 via disulfide bonds. A cytotoxic effect against ONS-76 cells was found with [3H]thymidine incorporation assay using the immunotoxin, but not against antigen-negative HuH-7 and SW480 cells. These results suggest that ONS-M21 could effectively deliver toxins, chemotherapeutic agents or radionuclei to malignant glioma specifically. PMID:9619874

Shimizu, K; Park, K C; Tamura, K; Kishima, H; Kawata, H; Yoshimura, Y; Sekimori, Y; Miyao, Y; Hayakawa, T

1998-05-15

325

Fidelity of DNA Replication by Extracts of Normal and Malignantly Transformed Human Cells1  

Microsoft Academic Search

To test the hypothesis that a imitator phenotype may be associated with carcinogenesis (L. A. Loeb, Cancer Res., 5\\/: 3074-3079, 1991), we have compared the fidelity of double-stranded DNA replication and the effi ciency of mismatch repair in extracts from normal diploid and malig nantly transformed human cells. Included was a diploid fibroblast strain and its transformed derivative, as well

Jayne C. Boyer; David C. Thomas; Veronica M. MÃ; Justin J. McCormick; Thomas A. Kunkel

1993-01-01

326

Modification of radiosensitivity in cancer treatment  

SciTech Connect

This book contains 27 selections divided among six sections. The section titles are: General Review, Chemical Protection, Hypoxic Cell Sensitizer, Biological Sensitization, Hyperthermia, and Cellular Radiosensitivity and its Mechanisms.

Sugahara, T.

1984-01-01

327

Radiosensitization of Thymidine in Deaerated Aqueous Solution.  

National Technical Information Service (NTIS)

This work investigates the mode of action of various radiosensitizing agents on the radio-induced degradation of thymidine in deaerated aqueous solution. A special effort was devoted to the separation of addition products formed by one of these substances...

M. Berger

1982-01-01

328

Exogenous delta-animolevulinic acid induces the porphyrin biosynthesis in human skin organ cultures with different porphyrin patterns in normal and malignant human tissue  

NASA Astrophysics Data System (ADS)

The carboxylation state of porphyrin metabolites causes their hydrophilic or lipophilic properties and subsequently their distribution in tissues, cells, and subcellular compartments. The profile of porphyrin metabolites either in normal skin or in malignant skin tumors after administration of (delta) -aminolevulinic acid has been studied in detail, yet. Explant cultures of normal skin and neoplastic tissues, e.g., keratoakanthoma and basal cell carcinoma, were incubated with 1 mM ALA for 36 h. Total porphyrin concentration and percentage of porphyrin metabolites were determined quantitatively in tissues and corresponding supernatants. Seventy - ninety percent of total porphyrins could be detected in the supernatants of all samples. The highly carboxylated porphyrins were the prevailing metabolites in the supernatants as well as in the tissues. The basal cell carcinoma produced significantly more protoporphyrin and the keratoakanthoma significantly more coproporphyrin as compared to normal skin. The results show that explant cultures offer an easy approach to examine the enzymatic capacity in porphyrin biosynthesis of various tissues. Benign and malignant human tissues produce different porphyrin metabolites, which may be useful for selective and more effective photodynamic diagnosis or therapy.

Fritsch, Clemens; Batz, Janine; Bolsen, Klaus; Schulte, Klaus; Ruzicka, Thomas; Goerz, Guenter

1994-10-01

329

Exogenous delta-animolevulinic acid induces the porphyrin biosynthesis in human skin organ cultures with different porphyrin patterns in normal and malignant human tissue  

NASA Astrophysics Data System (ADS)

The carboxylation state of porphyrin metabolites causes their hydrophilic or lipophilic properties and subsequently their distribution in tissues, cells, and subcellular compartments. The profile of porphyrin metabolites either in normal skin or in malignant skin tumors after administration of (delta) -aminolevulinic acid has been studied in detail, yet. Explant cultures of normal skin and neoplastic tissues, e.g., keratoakanthoma and basal cell carcinoma, were incubated with 1 mM ALA for 36 h. Total porphyrin concentration and percentage of porphyrin metabolites were determined quantitatively in tissues and corresponding supernatants. Seventy - ninety percent of total porphyrins could be detected in the supernatants of all samples. The highly carboxylated porphyrins were the prevailing metabolites in the supernatants as well as in the tissues. The basal cell carcinoma produced significantly more protoporphyrin and the keratoakanthoma significantly more coproporphyrin as compared to normal skin. The results show that explant cultures offer an easy approach to examine the enzymatic capacity in porphyrin biosynthesis of various tissues. Benign and malignant human tissues produce different porphyrin metabolites, which may be useful for selective and more effective photodynamic diagnosis or therapy.

Fritsch, Clemens; Batz, Janine; Bolsen, Klaus; Schulte, Klaus; Ruzicka, Thomas; Goerz, Guenter

1995-03-01

330

The calcium-binding protein S100P in normal and malignant human tissues  

Microsoft Academic Search

BACKGROUND: S100P is a Ca2+ binding protein overexpressed in a variety of cancers, and thus, has been considered a potential tumor biomarker. Very little has been studied about its normal expression and functions. METHODS: We examined S100P expression in normal human tissues by quantitative reverse transcription polymerase chain reaction and immunohistochemistry. S100P protein expression was also studied in a series

Seppo Parkkila; Pei-wen Pan; Aoife Ward; Adriana Gibadulinova; Ingrid Oveckova; Silvia Pastorekova; Jaromir Pastorek; Alejandra Rodriguez Martinez; Henrik O Helin; Jorma Isola

2008-01-01

331

Immune cytolysis of human malignant melanoma by antibody to oncofetal antigen I (OFA-I)  

Microsoft Academic Search

Oncofetal antigen I (OFA-I) has been identified by immunofluorescence and immune adherence (IA) as a membrane antigen on human tumor cells, which cross-reacts with fetal brain tissue. This antigen induces humoral antibody in patients with cancer. The present work was designed to evaluate the complement-dependent cytotoxic potential of anti-OFA-I antibody produced in melanoma patients against an OFA-I-positive melanoma cell line,

N. Sidell; R. F. Irie; D. L. Morton

1979-01-01

332

Immunohistochemical Expression of the Human Sodium\\/Iodide Symporter Distinguishes Malignant From Benign Gastric Lesions  

Microsoft Academic Search

Aim. Sodium\\/iodide symporter (NIS) is a transmembrane protein that mediates the transport of I?. The aim was to evaluate the immunohistochemical expression of the human homolog of NIS (hNIS) in a wide spectrum of gastric lesions. Materials and methods. Seventy-seven samples were stained immunohistochemically with a monoclonal antibody for hNIS, including 14 with normal gastric mucosa, 14 with chronic atrophic

Anna Farnedi; Leonardo H. Eusebi; Francesca Poli; Maria P. Foschini

2009-01-01

333

Epigenetic regulation of Vitamin D hydroxylase expression and activity in normal and malignant human prostate cells  

Microsoft Academic Search

It was previously suggested that the 25-Vitamin-D3-1?-hydroxylase (CYP27B1) is downregulated during human prostate tumor pathogenesis while the catabolic 25-Vitamin-D3-24-hydroxylase (CYP24) expression is increased. The latter could lead to resistance against the antimitotic, prodifferentiating activity of 1,25-dihydroxycholecalciferol. Our hypothesis was that regulation of Vitamin D hydroxylase expression during prostate tumor progression might be under epigenetic control. We demonstrate by real time

Maya Khorchide; Daniel Lechner; Heide S. Cross

2005-01-01

334

Preliminary micro-Raman images of normal and malignant human skin cells  

Microsoft Academic Search

Micro-Raman spectroscopy covering a frequency range from 200 to 4000 cm-1 was used to image human skin melanocytes and keratinocytes with a spatial resolution of 0.5 mum. The cells were either cultivated on glass microscope slides or were located within thin sections of skin biopsies mounted on low fluorescence BaF2. A commercially available system was used to obtain the spectra

Michael A. Short; Harvey Lui; David I. McLean; Haishan Zeng; Michael X. Chen

2006-01-01

335

Human IL18 Bioactivity in Hematological Malignancies with Highly Elevated Serum IL18 Levels  

Microsoft Academic Search

Interleukin-18 (IL-18) is a multifunctional cytokine of a 18.3 kD and is synthesized by Kupffer cells, activated macrophages, keratinocytes, intestinal epithelial cells, osteoblasts, adrenal cortex cells and murine diencephalon [8, 9, 10, 11, 12]. Murine IL-18 was purified from the extracts of liver tissues from P. acnes-primed and lipopolysaccharide-challenged mice [2]. In 1996, the human IL-18 was obtained by expression

Takayuki Takubo; Hisako Okura; Takeo Kumura; Saori Nishiki; Yoshimitsu Kinoshita; Ki-Ryang Koh; Kensuke Ohta; Takahisa Yamane; Masayuki Hino; Tomio Kamitani; Noriyuki Tatsumi

2000-01-01

336

Malignant Precursor Cells Pre-Exist in Human Breast DCIS and Require Autophagy for Survival  

Microsoft Academic Search

BackgroundWhile it is accepted that a majority of invasive breast cancer progresses from a ductal carcinoma in situ (DCIS) precursor stage, very little is known about the factors that promote survival of DCIS neoplastic cells within the hypoxic, nutrient deprived intraductal microenvironment.Methodology and Principal FindingsWe examined the hypothesis that fresh human DCIS lesions contain pre-existing carcinoma precursor cells. We characterized

Virginia Espina; Brian D. Mariani; Rosa I. Gallagher; Khoa Tran; Stacey Banks; Joy Wiedemann; Heather Huryk; Claudius Mueller; Luana Adamo; Jianghong Deng; Emanuel F. Petricoin; Lucia Pastore; Syed Zaman; Geetha Menezes; James Mize; Jasbir Johal; Kirsten Edmiston; Lance A. Liotta; Yu Wang

2010-01-01

337

Malignant Precursor Cells Pre-Exist in Human Breast DCIS and Require Autophagy for Survival  

PubMed Central

Background While it is accepted that a majority of invasive breast cancer progresses from a ductal carcinoma in situ (DCIS) precursor stage, very little is known about the factors that promote survival of DCIS neoplastic cells within the hypoxic, nutrient deprived intraductal microenvironment. Methodology and Principal Findings We examined the hypothesis that fresh human DCIS lesions contain pre-existing carcinoma precursor cells. We characterized these cells by full genome molecular cytogenetics (Illumina HumanCytoSNP profile), and signal pathway profiling (Reverse Phase Protein Microarray, 59 endpoints), and demonstrated that autophagy is required for survival and anchorage independent growth of the cytogenetically abnormal tumorigenic DCIS cells. Ex vivo organoid culture of fresh human DCIS lesions, without enzymatic treatment or sorting, induced the emergence of neoplastic epithelial cells exhibiting the following characteristics: a) spontaneous generation of hundreds of spheroids and duct-like 3-D structures in culture within 2–4 weeks; b) tumorigenicity in NOD/SCID mice; c) cytogenetically abnormal (copy number loss or gain in chromosomes including 1, 5, 6, 8, 13, 17) compared to the normal karyotype of the non-neoplastic cells in the source patient's breast tissue; d) in vitro migration and invasion of autologous breast stroma; and e) up-regulation of signal pathways linked to, and components of, cellular autophagy. Multiple autophagy markers were present in the patient's original DCIS lesion and the mouse xenograft. We tested whether autophagy was necessary for survival of cytogenetically abnormal DCIS cells. The lysosomotropic inhibitor (chloroquine phosphate) of autophagy completely suppressed the generation of DCIS spheroids/3-D structures, suppressed ex vivo invasion of autologous stroma, induced apoptosis, suppressed autophagy associated proteins including Atg5, AKT/PI3 Kinase and mTOR, eliminated cytogenetically abnormal spheroid forming cells from the organ culture, and abrogated xenograft tumor formation. Conclusions Cytogenetically abnormal spheroid forming, tumorigenic, and invasive neoplastic epithelial cells pre-exist in human DCIS and require cellular autophagy for survival.

Espina, Virginia; Mariani, Brian D.; Gallagher, Rosa I.; Tran, Khoa; Banks, Stacey; Wiedemann, Joy; Huryk, Heather; Mueller, Claudius; Adamo, Luana; Deng, Jianghong; Petricoin, Emanuel F.; Pastore, Lucia; Zaman, Syed; Menezes, Geetha; Mize, James; Johal, Jasbir; Edmiston, Kirsten; Liotta, Lance A.

2010-01-01

338

[Gemcitabine and ionizing radiations: radiosensitization or radio-chemotherapy combination].  

PubMed

Gemcitabine is a pyrimidine analog which has demonstrated antitumoral activity in a variety of solid tumors including bladder, non-small cell lung and pancreatic cancers. Gemcitabine is a potent radiosensitizer of human tumor cells. This review summarizes preclinical studies designed to elucidate the mechanism of action of gemcitabine with ionizing radiation. Phase I-II ongoing trials of combination of radiation therapy and gemcitabine are trying to determine the optimal dose and schedule which could be used in daily clinical activity. The mechanism of radiosensitization is thought to be simultaneously gemcitabine-induced dATP (deoxyadenosine triphosphate) depletion and cell cycle redistribution into the S phase. Although there are no real study which has proven supra-additive combination, the recent acute side effects in several clinical studies oblige physicists to determine with precision the maximum tolerated dose of gemcitabine in association with ionizing radiation. Radiosensitization conditions can be obtained either with a long exposition to a low concentration or a short exposition to a high concentration. Radiation sensitivity begin to be detected four hours after treatment for 48 hours. A dose about 100 mg/m2/week of gemcitabine could be used with radiation therapy according to recent phase I results. This limiting dose is approaching to a radiosensitization context where the effect of one agent is increased by another agent which is inactive or poorly active for the effect under consideration. In this type of regimen, the two modalities do interact with a frequent inhibition of recovery from potentially lethal damage and a probably increase of late side effects of radiation therapy. In contrast, radio-chemotherapy combination is used for a therapeutic advantage when the drug by itself is active against the tumor but does not enhance late side effects of radiation on the critical normal tissues within the irradiated volume. Gemcitabine surely is a strong radiosensitizer even at low doses with future extended combined modality therapeutic indications. The ultimate goal of combined treatments should be an increased therapeutic ratio. PMID:12016038

Azria, David; Jacot, William; Prost, Patricia; Culine, Stéphane; Ychou, Marc; Lemanski, Claire; Dubois, Jean-Bernard

2002-04-01

339

Transcutaneous Application of Carbon Dioxide (CO2) Induces Mitochondrial Apoptosis in Human Malignant Fibrous Histiocytoma In Vivo  

PubMed Central

Mitochondria play an essential role in cellular energy metabolism and apoptosis. Previous studies have demonstrated that decreased mitochondrial biogenesis is associated with cancer progression. In mitochondrial biogenesis, peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PGC-1?) regulates the activities of multiple nuclear receptors and transcription factors involved in mitochondrial proliferation. Previously, we showed that overexpression of PGC-1? leads to mitochondrial proliferation and induces apoptosis in human malignant fibrous histiocytoma (MFH) cells in vitro. We also demonstrated that transcutaneous application of carbon dioxide (CO2) to rat skeletal muscle induces PGC-1? expression and causes an increase in mitochondrial proliferation. In this study, we utilized a murine model of human MFH to determine the effect of transcutaneous CO2 exposure on PGC-1? expression, mitochondrial proliferation and cellular apoptosis. PGC-1? expression was evaluated by quantitative real-time PCR, while mitochondrial proliferation was assessed by immunofluorescence staining and the relative copy number of mitochondrial DNA (mtDNA) was assessed by real-time PCR. Immunofluorescence staining and DNA fragmentation assays were used to examine mitochondrial apoptosis. We also evaluated the expression of mitochondrial apoptosis related proteins, such as caspases, cytochorome c and Bax, by immunoblot analysis. We show that transcutaneous application of CO2 induces PGC-1? expression, and increases mitochondrial proliferation and apoptosis of tumor cells, significantly reducing tumor volume. Proteins involved in the mitochondrial apoptotic cascade, including caspase 3 and caspase 9, were elevated in CO2 treated tumors compared to control. We also observed an enrichment of cytochrome c in the cytoplasmic fraction and Bax protein in the mitochondrial fraction of CO2 treated tumors, highlighting the involvement of mitochondria in apoptosis. These data indicate that transcutaneous application of CO2 may represent a novel therapeutic tool in the treatment of human MFH.

Onishi, Yasuo; Kawamoto, Teruya; Ueha, Takeshi; Kishimoto, Kenta; Hara, Hitomi; Fukase, Naomasa; Toda, Mitsunori; Harada, Risa; Minoda, Masaya; Sakai, Yoshitada; Miwa, Masahiko; Kurosaka, Masahiro; Akisue, Toshihiro

2012-01-01

340

Astrocyte-specific expression of activated p21-ras results in malignant astrocytoma formation in a transgenic mouse model of human gliomas.  

PubMed

Activation of the p21-ras signaling pathway from aberrantly expressed receptors promotes the growth of malignant human astrocytomas. We developed a transgenic mouse astrocytoma model using the glial fibrillary acidic protein (GFAP) promoter to express oncogenic V(12)Ha-ras, specifically in astrocytes. The development of GFAP-immunoreactive astrocytomas was directly proportional to the level of V(12)Ha-ras transgene expression. Chimeras expressing high levels of V(12)Ha-ras in astrocytes died from multifocal malignant astrocytomas within 2 weeks, whereas those with moderate levels went to germ-line transmission. Ninety-five percent of these mice died from solitary or multifocal low- and high-grade astrocytomas within 2-6 months. These transgenic astrocytomas are pathologically similar to human astrocytomas, with a high mitotic index, nuclear pleomorphism, infiltration, necrosis, and increased vascularity. Derivative astrocytoma cells are tumorigenic upon inoculation in another host. The transgenic astrocytomas exhibit additional molecular alterations associated with human astrocytomas, including a decreased or absent expression of p16, p19, and PTEN as well as overexpression of EGFR, MDM2, and CDK4. Cytogenetic analysis revealed consistent clonal aneuploidies of chromosomal regions syntenic with comparable loci altered in human astrocytomas. Therefore, this transgenic mouse astrocytoma model recapitulates many of the molecular histopathological and growth characteristics of human malignant astrocytomas in a reproducible, germ-line-transmitted, and high-penetrance manner. PMID:11325859

Ding, H; Roncari, L; Shannon, P; Wu, X; Lau, N; Karaskova, J; Gutmann, D H; Squire, J A; Nagy, A; Guha, A

2001-05-01

341

Drug-induced alterations in tumour perfusion yield increases in tumour cell radiosensitivity  

PubMed Central

The perfusion of human tumour xenografts was manipulated by administration of diltiazem and pentoxifylline, and the extent that observed changes in tumour perfusion altered tumour radiosensitivity was determined. 2 tumour systems having intrinsically different types of hypoxia were studied. The responses of SiHa tumours, which have essentially no transient hypoxia, were compared to the responses of WiDr tumours, which contain chronically and transiently hypoxic cells. We found that relatively modest increases in net tumour perfusion increased tumour cell radiosensitivity in WiDr tumours to a greater extent than in SiHa tumours. Moreover, redistribution of blood flow within WiDr tumours was observed on a micro-regional level that was largely independent of changes in net tumour perfusion. Through fluorescence-activated cell sorting coupled with an in vivo–in vitro cloning assay, increases in the radiosensitivity of WiDr tumour cells at intermediate levels of oxygenation were observed, consistent with the expectation that a redistribution of tumour blood flow had increased oxygen delivery to transiently hypoxic tumour cells. Our data therefore suggest that drug-induced changes in tumour micro-perfusion can alter the radiosensitivity of transiently hypoxic tumour cells, and that increasing the radiosensitivity of tumour cells at intermediate levels of oxygenation is therapeutically relevant. © 2001 Cancer Research Campaign ??http://www.bjcancer.com

Bennewith, K L; Durand, R E

2001-01-01

342

Expression of tropomyosin isoforms in benign and malignant human breast lesions.  

PubMed

High molecular weight tropomyosins (tms) are commonly down-regulated in fibroblasts transformed by oncogenes. Previous studies have also demonstrated that specific tm isoforms are down-regulated in human breast carcinoma cell lines. We examined tropomyosin isoforms in cells prepared from non-cancerous breast lesions and primary human breast carcinomas. The average level of expression of all three high molecular weight tm isoforms (tm 1-3) in carcinomas was generally found to be less than 25% of that observed in non-cancerous breast lesions. Interestingly, the expression of tm 1 was found to be 1.7-fold higher in primary tumours with metastatic spread to axillary lymph nodes compared with primary tumours with no evidence of metastasis (p<0.05). Similarly, tm 1 expression was higher in two 12V-H-ras transformed fibroblast cell lines capable of experimental metastasis compared with three weakly metastatic cell lines. We conclude from these studies that expression of high molecular weight tm isoforms is low in primary breast carcinomas, and that metastatic tumours express relatively high levels of tm 1. PMID:8611405

Franzén, B; Linder, S; Uryu, K; Alaiya, A A; Hirano, T; Kato, H; Auer, G

1996-04-01

343

Expression of tropomyosin isoforms in benign and malignant human breast lesions.  

PubMed Central

High molecular weight tropomyosins (tms) are commonly down-regulated in fibroblasts transformed by oncogenes. Previous studies have also demonstrated that specific tm isoforms are down-regulated in human breast carcinoma cell lines. We examined tropomyosin isoforms in cells prepared from non-cancerous breast lesions and primary human breast carcinomas. The average level of expression of all three high molecular weight tm isoforms (tm 1-3) in carcinomas was generally found to be less than 25% of that observed in non-cancerous breast lesions. Interestingly, the expression of tm 1 was found to be 1.7-fold higher in primary tumours with metastatic spread to axillary lymph nodes compared with primary tumours with no evidence of metastasis (p<0.05). Similarly, tm 1 expression was higher in two 12V-H-ras transformed fibroblast cell lines capable of experimental metastasis compared with three weakly metastatic cell lines. We conclude from these studies that expression of high molecular weight tm isoforms is low in primary breast carcinomas, and that metastatic tumours express relatively high levels of tm 1. Images Figure 1

Franzen, B.; Linder, S.; Uryu, K.; Alaiya, A. A.; Hirano, T.; Kato, H.; Auer, G.

1996-01-01

344

A clinical nude mouse metastatic model for highly malignant human pancreatic cancer.  

PubMed

Pancreatic cancer is a highly aggressive and treatment-refractory cancer. A clinically-relevant animal model is necessary to develop therapy for metastatic pancreatic cancer. In this study we evaluated the efficacy of mitomycin C (MMC) and 5-FU against the human pancreatic adenocarcinoma cell line PAN-12 in an orthotopic human metastatic pancreatic cancer nude mice model. The model is constructed by surgical orthotopic implantation (SOI) of histologically intact tumor tissue in the tail portion of the pancreas near the spleen. PAN-12 grew very aggressively in the control group of nude mice with extensive local invasion and distant metastasis to various organs with a propensity for the lung but to other organs as well, including the liver, kidney and regional and distant lymph nodes. In a striking effect none of the mice in the MMC-treated group developed tumor. Although mice in the 5-FU treated group survived statistically significantly longer than those in the untreated control, the overall incidence of metastasis in these mice was equivalent to those in the control. However no liver or kidney metastases were found in the 5-FU treated animals perhaps accounting in part for their longer survival. This "clinical" nude mouse model of highly metastatic pancreatic cancer can now be used to discover new effective agents for this disease. PMID:8687107

An, Z; Wang, X; Kubota, T; Moossa, A R; Hoffman, R M

1996-01-01

345

Mitochondrial alteration in malignantly transformed human small airway epithelial cells induced by alpha particles  

PubMed Central

Human small airway epithelial cells (SAECs) immortalized with human telomerase reverse transcriptase (h-TERT) were exposed to either a single or multiple doses of ? particles. Irradiated cells showed a dose-dependent cytotoxicity and progressive neoplastic transformation phenotype. These included an increase in saturation density of growth, a greater resistance to PALA, faster anchorage-independent growth, reinforced cell invasion and c-Myc expression. In addition, the transformed cells formed progressively growing tumors upon inoculation into athymic nude mice. Specifically, ?-irradiation induced damage to both mitochondrial DNA (mtDNA) and mitochondrial functions in transformed cells as evidenced by increased mtDNA copy number and common deletion, decreased oxidative phosphorylation (OXPHOS) activity as measured by cytochrome C oxidase (COX) activity and oxygen consumption. There was a linear correlation between mtDNA copy number, common deletion, COX activity and cellular transformation represented by soft agar colony formation and c-Myc expression. These results suggest that mitochondria are associated with neoplastic transformation of SAEC cells induced by ? particles, and that the oncogenesis process may depend not only on the genomes inside the nucleus, but also on the mitochondrial DNA outside the nucleus.

Zhang, Suping; Wen, Gengyun; Huang, Sarah XL; Wang, Jianrong; Tong, Jian; Hei, Tom K.

2012-01-01

346

Transplantable malignant melanoma in LT.B6 congenic mice resembling pigmented epithelioid melanocytoma in humans  

PubMed Central

Genetically engineered mouse models have been generated to recapitulate major signaling pathways deregulated in melanoma. Although these models are invaluable to delineate the relationship between gene mutations and targeted therapeutics, no spontaneously occurring melanomas are available in laboratory mice, which might be used to discover novel disrupted pathways, other than the widely studied MAPK, PI3-AKT and CDK4-INK4A-RB1. We report multiple spontaneously occurring melanomas on the tail of LT.B6 congenic strain, commonly used to study spontaneous ovarian teratomas. We present the evidence of spontaneous mouse melanoma and successful transplantation into 2 out of 2 mice, thereby enabling a complete histopathologic and clinical characterization. The histopathology of LT.B6 melanomas remarkably resembled a human melanoma subtype, pigmented epithelioid melanocytoma (PEM); and their clinical behavior was similar in indolent growth, metastasis to local lymph nodes and lack of liver metastasis. Lung metastasis was unique in the mice. Using qRT-PCR, we detected the expression of two melanocyte specific genes, Tyrp1 and Mitf, in the transplanted primary tumors and nodal metastases but not liver, confirming the histopathology. This mouse model closely resembled a low-grade variant of human melanoma and could provide the opportunity to globally investigate the genetic and epigenetic alterations associated with metastasis.

Dadras, Soheil S; Silva, Kathleen A.; King, Lloyd E.; Sundberg, John P.

2014-01-01

347

Anatomy of smooth muscle cells in nonmalignant and malignant human prostate tissue.  

PubMed

Differently graded areas of human prostate adenocarcinoma were examined after Masson's trichrome staining or immunohistochemistry for smooth muscle alpha-actin, type IV collagen and laminin. In addition, the ultrastructure of the prostatic smooth muscle cells (SMC) during glandular proliferation and epithelial invasion in selected tumors was studied. The SMC formed a thick layer below the epithelial structures in unaffected areas and were closely associated with each other in homotypic interactions. As the tumor grade increased, the SMC gradually lost interactions with each other and became atrophic. With the growth of the epithelial compartment, the SMC initially segregated to the tumor periphery and the intercellular spaces increased. In high grade tumors, the epithelial cancer cells invaded the spaces between the SMC. Immunohistochemical analysis of the basal membrane revealed increased disruption of the usually thick basal membrane, which became thinner and faintly stained with each of the antibodies used. We conclude that most SMC become atrophic following epithelial invasion in human tumors and that degradation of the basal membrane is an important factor in this process. At the ultrastructural level, different SMC phenotypes occur in prostatic tissues during epithelial invasion. Interconversion between these phenotypes is suggested and a probable relationship among them is proposed. PMID:18727055

Taboga, Sebastião R; Scortegagna, Eduardo; Siviero, Maristela P; Carvalho, Hernandes F

2008-09-01

348

Combined RAF1 protein expression and p53 mutational status provides a strong predictor of cellular radiosensitivity  

PubMed Central

The tumour suppressor gene, p53, and genes coding for positive signal transduction factors can influence transit through cell-cycle checkpoints and modulate radiosensitivity. Here we examine the effects of RAF1 protein on the rate of exit from a G2/M block induced by ?-irradiation in relation to intrinsic cellular radiosensitivity in human cell lines expressing wild-type p53 (wtp53) protein as compared to mutant p53 (mutp53) protein. Cell lines which expressed mutp53 protein were all relatively radioresistant and exhibited no relationship between RAF1 protein and cellular radiosensitivity. Cell lines expressing wtp53 protein, however, showed a strong relationship between RAF1 protein levels and the radiosensitivity parameter SF2. In addition, when post-irradiation perturbation of G2/M transit was compared using the parameter T50 (time after the peak of G2/M delay at which 50% of the cells had exited from a block induced by 2 Gy of irradiation), RAF1 was related to T50 in wtp53, but not mutp53, cell lines. Cell lines which expressed wtp53 protein and high levels of RAF1 had shorter T50s and were also more radiosensitive. These results suggest a cooperative role for wtp53 and RAF1 protein in determining cellular radiosensitivity in human cells, which involves control of the G2/M checkpoint. © 2000 Cancer Research Campaign

Warenius, H M; Jones, M; Gorman, T; McLeish, R; Seabra, L; Barraclough, R; Rudland, P

2000-01-01

349

Experimental thermoradiotherapy in malignant hepatocellular carcinoma  

Microsoft Academic Search

PurposeThe human liver is known to be a relatively radiosensitive organ that develops clinically relevant late radiation hepatitis subsequent to whole liver treatment with total doses above 30 Gy in conventional fractionation. Experimental data, as well as clinical series, have demonstrated that hyperthermia of solid tumors in addition to radiotherapy enhances tumor growth inhibition and tumor control probability. We therefore

Thomas Hehr; Wilfried Budach; Ulf Lamprecht; Claus Belka; Johannes Classen; Jochen Trübenbach; Manfred Wehrmann; Klaus Dietz; Michael Bamberg

2003-01-01

350

Lymphocyte colony forming units and its application to the study of radiosensitivity.  

National Technical Information Service (NTIS)

Kinetics and radiosensitivity of human lymphocytes were studied by the techniques of monolayer agar culture and liquid culture in vitro. In the experiments of lymphocyte kinetics, PHA was designated as a motogen for T lymphocyte. LPS, MEBC and BSA were ch...

X. Ma T. Wang H. Wang

1991-01-01

351

Monoclonal antibody to HER-2/neureceptor modulates repair of radiation-induced DNA damage and enhances radiosensitivity of human breast cancer cells overexpressing this oncogene.  

PubMed

The management of human breast cancer frequently includes radiation therapy as an important intervention, and improvement in the clinical efficacy of radiation is desirable. Overexpression of the HER-2 growth factor receptor occurs in 25-30% of human breast cancers and correlates with poor clinical outcome, including earlier local relapse following conservative surgery accompanied by radiation therapy. In breast cancer cells with overexpression of HER-2 receptor, recombinant humanized monoclonal antibodies (rhuMAbs) to HER-2 receptors (rhuMAb HER-2) decrease cell proliferation in vitro and reduce tumor formation in nude mice. Therapy with rhuMAb HER-2 enhances tumor sensitivity to radiation at doses of 1-5 Gy, exceeding remission rates obtained with radiation alone. This benefit is specific to cells with HER-2 overexpression and does not occur in cells without overexpression. Treatment of cells with radiation (2-4 Gy) alone provokes a marked increase in unscheduled DNA synthesis, a measure of DNA repair, but HER-2-overexpressing cells treated with a combination of rhuMAb HER-2 and radiation demonstrate a decrease of unscheduled DNA synthesis to 25-44% of controls. Using an alternate test of DNA repair, i.e., radiation-damaged or undamaged reporter DNA, we introduced a cytomegalovirus-driven beta3-galactosidase into HER-2-overexpressing breast cancer cells that had been treated with rhuMAb HER-2 or control. At 24 h posttransfection, the extent of repair assayed by measuring reporter DNA expression was high after exposure to radiation alone but significantly lower in cells treated with combined radiation and rhuMAb HER-2 therapy. To further characterize effects of rhuMAb HER-2 and the combination of antibody and radiation on cell growth, analyses of cell cycle phase distribution were performed. Antibody reduces the fraction of HER-2-overexpressing breast cancer cells in S phase at 24 and 48 h. Radiation treatment is also known to promote cell cycle arrest, predominantly at G1, with low S-phase fraction at 24 and 48 h. In the presence of rhuMAb HER-2, radiation elicits a similar reduction in S phase at 24 h, but a significant reversal of this arrest appears to begin 48 h postradiation exposure. The level of S-phase fraction at 48 h is significantly greater than that found at 24 h with the combined antibody-radiation therapy, suggesting that early escape from cell cycle arrest in the presence of antireceptor antibody may not allow sufficient time for completion of DNA repair in HER-2-overexpressing cells. Because it is well known that failure of adequate p21WAF1 induction after DNA damage is associated with failure of cell cycle arrest, we also assessed the activity of this critical mediator of the cellular response to DNA damage. The results show induction of p21WAF1 transcripts and protein product at 6, 12, and 24 h after radiation treatment; however, increased levels of p21WAF1 transcript and protein are not sustained in HER-2-overexpressing cells exposed to radiation in the presence of rhuMAb HER-2. Although transcript and protein levels increase at 6-12 h, they are both diminished by 24 h. Levels of p21WAF1 transcript and protein at 24 h are significantly lower than in cells treated by radiation without antibody. A reduction in the basal level of p21WAF1 transcript also occurred after 12-24 h exposure to antibody alone. The effect of HER-2 antibody may be related to tyrosine phosphorylation of p21WAF1 protein. Tyrosine phosphorylation of p21WAF1 is increased after treatment with radiation alone, but phosphorylation is blocked by combined treatment with antireceptor antibody and radiation. This dysregulation of p21WAF1 in HER-2-overexpressing breast cells after treatment with rhuMAb HER-2 and radiation appears to be independent of p53 expression levels but does correlate with reduced levels of mdm2 protein. (ABSTRACT TRUNCATED) PMID:10096569

Pietras, R J; Poen, J C; Gallardo, D; Wongvipat, P N; Lee, H J; Slamon, D J

1999-03-15

352

Human papillomavirus type 16 DNA-induced malignant transformation of NIH 3T3 cells.  

PubMed Central

A biological function for human papillomavirus 16 (HPV 16) DNA was demonstrated by transformation of NIH 3T3 cells. HPV 16 DNA has been found frequently in genital cancer and has been classified as a papillomavirus on the basis of DNA homology. A recombinant HPV 16 DNA (pSHPV16d), which contains a head-to-tail dimer of the full-length HPV 16 genome, induced morphologic transformation; the transformed cells were tumorigenic in nude mice. Expression of transforming activity was unique because of the long latency period (more than 4 weeks) required for induction of morphologic transformation and because the transfected DNA existed primarily in a multimeric form with some rearrangements. Furthermore, virus-specific RNAs were expressed in the transformants. The transformation of NIH 3T3 cells provides a model for analyzing the functions of HPV 16, which is associated with cervical carcinomas. Images

Yasumoto, S; Burkhardt, A L; Doniger, J; DiPaolo, J A

1986-01-01

353

Cytomodulation of interleukin-2 effect by L-2-oxothiazolidine-4-carboxylate on human malignant melanoma.  

PubMed

Glutathione (GSH), the most prevalent intracellular non-protein thiol, plays an important role in the interleukin-2 (IL-2)-induced proliferative activity of normal and tumour cells expressing IL-2 receptor (IL-2R). In the present study, we investigate the effect of IL-2 on proliferation of the human melanoma A375 cell line, and the possible selective cytomodulation effect of this cytokine by L-2-oxothiazolidine-4-carboxylate (OTZ) on these melanoma cells and on human peripheral blood mononuclear cells (PBMCs). We found that recombinant IL-2 (rIL-2) significantly increased the proliferation rate of A375 melanoma cells, which was associated with an increase in GSH levels, the enhancement of IL-2Ralpha expression and the endogenous production of IL-2 in these tumour cells. In contrast, OTZ decreased GSH content and the proliferation rate of A375 cells, and abrogated the growth-promoting effects of rIL-2. Thus, compared to cells treated with rIL-2, pre-treatment with OTZ reduced IL-2Ralpha expression, and also decreased the consumption of rIL-2 and the endogenous secretion of IL-2 by these tumour cells. With regard to PBMCs, the combination of OTZ plus rIL-2 resulted in a more rapid and greater increase of IL-2Ralpha expression than rIL-2 alone, with the proliferation rate being similar in the first 24 h, but with a lower PBMC' count found thereafter compared to rIL-2 treatment alone. These results suggest that OTZ plays a crucial role in obtaining a selective cytomodulation of rIL-2, enabling it to exert its growth-promoting effect on normal cells, but not on melanoma cells, thereby possibly improving biochemotherapy with rIL-2. PMID:16220324

del Olmo, Maite; Alonso-Varona, Ana; Castro, Begoña; Bilbao, Pedro; Palomares, Teodoro

2006-08-01

354

Identification of miRNA-103 in the Cellular Fraction of Human Peripheral Blood as a Potential Biomarker for Malignant Mesothelioma - A Pilot Study  

PubMed Central

Background To date, no biomarkers with reasonable sensitivity and specificity for the early detection of malignant mesothelioma have been described. The use of microRNAs (miRNAs) as minimally-invasive biomarkers has opened new opportunities for the diagnosis of cancer, primarily because they exhibit tumor-specific expression profiles and have been commonly observed in blood of both cancer patients and healthy controls. The aim of this pilot study was to identify miRNAs in the cellular fraction of human peripheral blood as potential novel biomarkers for the detection of malignant mesothelioma. Methodology/Principal Findings Using oligonucleotide microarrays for biomarker identification the miRNA levels in the cellular fraction of human peripheral blood of mesothelioma patients and asbestos-exposed controls were analyzed. Using a threefold expression change in combination with a significance level of p<0.05, miR-103 was identified as a potential biomarker for malignant mesothelioma. Quantitative real-time PCR (qRT-PCR) was used for validation of miR-103 in 23 malignant mesothelioma patients, 17 asbestos-exposed controls, and 25 controls from the general population. For discrimination of mesothelioma patients from asbestos-exposed controls a sensitivity of 83% and a specificity of 71% were calculated, and for discrimination of mesothelioma patients from the general population a sensitivity of 78% and a specificity of 76%. Conclusions/Significance The results of this pilot study show that miR-103 is characterized by a promising sensitivity and specificity and might be a potential minimally-invasive biomarker for the diagnosis of mesothelioma. In addition, our results support the concept of using the cellular fraction of human blood for biomarker discovery. However, for early detection of malignant mesothelioma the feasibility of miR-103 alone or in combination with other biomarkers needs to be analyzed in a prospective study.

Weber, Daniel G.; Johnen, Georg; Bryk, Oleksandr; Jockel, Karl-Heinz; Bruning, Thomas

2012-01-01

355

p16(INK4a) is a useful marker of human papillomavirus integration allowing risk stratification for cervical malignancies.  

PubMed

The present study was conducted to assess utility of p16(INK4a) immunopositivity as a surrogate marker for genomic integration of high-risk human papillomavirus infection (hrHPV). A total of 29 formalin-fixed, paraffin-embedded cervical low-grade squamous intraepithelial lesions (LSILs), 27 high-grade squamous intraepithelial lesions (HSILs) and 53 invasive squamous cell carcinomas (SCCs), histologically-diagnosed between 1st January 2006 to 31st December 2008 at the University of Malaya Medical Centre were stained for p16(INK4a) (CINtec Histology Kit (REF 9511, mtm laboratories AG, Heidelberg, Germany). Immunopositvity was defined as diffuse staining of the squamous cell cytoplasm and or nucleus (involving > 75% of the intraepithelial lesions or SCCs). Staining of basal and parabasal layers of intraepithelial lesions was pre-requisite. One (3.4%) LSIL, 24 (88.9%) HSIL and 46 (86.8%) SCC were p16(INK4a) immunopositive. All normal squamous epithelium did not express p16(INK4). p16(INK4a) expression was significantly lower (p<0.05) in LSIL compared with HSIL and SCC with no difference in expression between HSIL and SCC.The increased p16(INK4a) immunopositivity in HSIL and SCC appears in line with the integrated existence of the hrHPV and may provide more insightful information on risk of malignant transformation of cervical squamous intraepithelial lesions than mere hrHPV detection. PMID:22524808

Cheah, Phaik-Leng; Looi, Lai-Meng; Teoh, Kean-Hooi; Mun, Kein-Seong; Nazarina, Abdul Rahman

2012-01-01

356

Comparative Genomic Hybridization of Human Malignant Gliomas Reveals Multiple Amplification Sites and Nonrandom Chromosomal Gains and Losses  

PubMed Central

Nine human malignant gliomas (2 astrocytomas grade III and 7 glioblastomas) were analyzed using comparative genomic hybridization (CGH). In addition to the amplification of the EGFR gene at 7p12 in 4 of 9 cases, six new amplification sites were mapped to 1q32, 4q12, 7q21.1, 7q21.2-3, 12p, and 22q12. Nonrandom chromosomal gains and losses were identified with overrepresentation of chromosome 7 and underrepresentation of chromosome 10 as the most frequent events (1 of 2 astrocytomas, 7 of 7 glioblastomas). Gain of a part or the whole chromosome 19 and losses of chromosome bands 9pter-23 and 22q13 were detected each in five cases. Loss of chromosome band 17p13 and gain of chromosome 20 were revealed each in three cases. The validity of the CGH data was confirmed using interphase cytogenetics with YAC clones, chromosome painting in tumor metaphase spreads, and DNA fingerprinting. A comparison of CGH data with the results of chromosome banding analyses indicates that metaphase spreads accessible in primary tumor cell cultures may not represent the clones predominant in the tumor tissue ImagesFigure 1Figure 4Figure 6

Schrock, Evelin; Thiel, Gundula; Lozanova, Tanka; du Manoir, Stanislas; Meffert, Marie-Christine; Jauch, Anna; Speicher, Michael R.; Nurnberg, Peter; Vogel, Siegfried; Janisch, Werner; Donis-Keller, Helen; Ried, Thomas; Witkowski, Regine; Cremer, Thomas

1994-01-01

357

Highly efficient tumor transduction and antitumor efficacy in experimental human malignant mesothelioma using replicating gibbon ape leukemia virus.  

PubMed

Retroviral replicating vectors (RRVs) have been shown to achieve efficient tumor transduction and enhanced therapeutic benefit in a wide variety of cancer models. Here we evaluated two different RRVs derived from amphotropic murine leukemia virus (AMLV) and gibbon ape leukemia virus (GALV), in human malignant mesothelioma cells. In vitro, both RRVs expressing the green fluorescent protein gene efficiently replicated in most mesothelioma cell lines tested, but not in normal mesothelial cells. Notably, in ACC-MESO-1 mesothelioma cells that were not permissive for AMLV-RRV, the GALV-RRV could spread efficiently in culture and in mice with subcutaneous xenografts by in vivo fluorescence imaging. Next, GALV-RRV expressing the cytosine deaminase prodrug activator gene showed efficient killing of ACC-MESO-1 cells in a prodrug 5-fluorocytosine dose-dependent manner, compared with AMLV-RRV. GALV-RRV-mediated prodrug activator gene therapy achieved significant inhibition of subcutaneous ACC-MESO-1 tumor growth in nude mice. Quantitative reverse transcription PCR demonstrated that ACC-MESO-1 cells express higher PiT-1 (GALV receptor) and lower PiT-2 (AMLV receptor) compared with normal mesothelial cells and other mesothelioma cells, presumably accounting for the distinctive finding that GALV-RRV replicates much more robustly than AMLV-RRV in these cells. These data indicate the potential utility of GALV-RRV-mediated prodrug activator gene therapy in the treatment of mesothelioma. PMID:24201868

Kubo, S; Takagi-Kimura, M; Logg, C R; Kasahara, N

2013-12-01

358

Dasatinib synergizes with JSI-124 to inhibit growth and migration and induce apoptosis of malignant human glioma cells  

PubMed Central

Background: Src family kinases (SFK) collectively regulate a variety of cellular functions in many cancer types, including proliferation, invasion, motility, survival, differentiation, and angiogenesis. Although Dasatinib (BMS-354825), an ATP-competitive, small molecule tyrosine kinase inhibitor, suppresses the activity of SFKs at nanomolar concentrations, IC50 values for antiproliferative effects in glioma cell lines were well above the clinically achievable range, suggesting the need to interfere with other components of receptor-induced downstream signaling in order to achieve an optimal therapeutic effect. Materials and Methods: The cytotoxic effects of combining Src and STAT3 inhibition on glioma cell lines were evaluated using assays to measure cell proliferation, apoptosis and migration. Western blotting and immunocytochemistry was used to monitor its effects on cell signaling and morphology. Results: Silencing Src and STAT3 expression each partially inhibited cell proliferation and migration. In addition, JSI-124 significantly enhanced the efficacy of dasatinib in vitro. Combination of dasatinib and JSI-124 achieved significant inhibition of migration in all cell lines, which correlated with the inhibition of Src and downstream mediators of adhesion (e.g. focal adhesion kinase). Cells exposed to dasatinib and JSI-124 exhibited morphological changes that were consistent with an upstream role for Src in regulating focal adhesion complexes. Conclusions: Targeting the Src and STAT pathways may contribute to the treatment of cancers that demonstrate increased levels of these signaling mediators, including malignant human glioma. Clinical studies in these tumor types are warranted.

Premkumar, Daniel R.; Jane, Esther P.; Agostino, Naomi R.; Scialabba, Joseph L.; Pollack, Ian F.

2010-01-01

359

Malignant transformation of diploid human fibroblasts by transfection of oncogenes. Part 2, Progress report, July 1989--June 1992  

SciTech Connect

This document consist of brief reports prepared by postdoctoral students supported by the project, each describing his accomplishments under the grant. Topics include (1) Malignant Transformation of MSU-1. 1 Cells by Gamma Radiation, (2) Correlation between Levels of ras Expression and Presence of Transformed Phenotypes Including Tumorigenicity, Using a Modulatable Promoter, (3) Relation between Specific rad Oncogene Expression, (4) Correlation of Genetic Changes in Fibroblastic Tumors with Malignancies, (5)Transformation of MSU-1.1 Cells by sis Oncogene, (6) Malignant Transformation of MSU-1.0 Cells, (7) Correlation of Urokinase Plasminogen Activation (mu-PA) with Malignant Phenotype, (8)Two Dimensional Gel Electrophoresis Studies of the Proteins of the Major Cell Strains of the MSU-1 Family of Cells, and (9) Correlation between Proteinase Activity Levels and Malignancy.

McCormick, J.J.

1992-12-31

360

Effect of Paris saponin I on radiosensitivity in a gefitinib-resistant lung adenocarcinoma cell line  

PubMed Central

Previous studies have observed that Paris saponin I (PSI) exerts a wide range of pharmacological activities, including cytotoxic activity against a number of malignancies, such as non-small cell lung cancers. The present study aimed to investigate the radiosensitization of PSI treatment on a gefitinib-resistant lung adenocarcinoma cell line, PC-9-ZD, and its possible mechanism. A 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide assay was used to determine the growth inhibition effect of PSI. A clonogenic assay was performed to determine the radiosensitizing effect of PSI treatment on the PC-9-ZD cell line. A single-hit multi-target model was used to plot survival curves and calculate sensitizing enhancement ratios. The cell cycle was analyzed by flow cytometry and cell apoptosis was analyzed with fluorescein-isothiocyanate-Annexin V/propidium iodide and Hoechst staining. The expression levels of the proteins were detected by western blotting. There was a significant reduction observed in the proliferation of the PC-9-ZD cell lines that were treated with PSI. PSI enhanced the radiosensitivity of the PC-9-ZD cells with a sensitization enhancement ratio of 1.77. Furthermore, PSI induced G2/M arrest and apoptosis of the irradiated PC-9-ZD cells. Notably, B-cell lymphoma 2 (Bcl-2) was downregulated, and caspase-3, Bcl-2-like protein 4 (Bax) and cyclin-dependent kinase inhibitor 1 (P21waf1/cip1) were upregulated by the PSI treatment. The present study showed that PSI treatment exhibited potent radiosensitivity against gefitinib-resistant PC-9-ZD cells in vitro. This radiosensitivity was associated with cell cycle arrest at the G2/M phase, and apoptosis via an increase in caspase-3, Bax and P21waf1/cip1 as well as a decrease in Bcl-2 production.

JIANG, HAO; ZHAO, PENGJUN; FENG, JIANGUO; SU, DAN; MA, SHENGLIN

2014-01-01

361

Prostate-Specific Natural Health Products (Dietary Supplements) Radiosensitize Normal Prostate Cells  

SciTech Connect

Purpose: Prostate-specific health products (dietary supplements) are taken by cancer patients to alleviate the symptoms linked with poor prostate health. However, the effect of these agents on evidence-based radiotherapy practice is poorly understood. The present study aimed to determine whether dietary supplements radiosensitized normal prostate or prostate cancer cell lines. Methods and Materials: Three well-known prostate-specific dietary supplements were purchased from commercial sources available to patients (Trinovin, Provelex, and Prostate Rx). The cells used in the study included normal prostate lines (RWPE-1 and PWR-1E), prostate tumor lines (PC3, DU145, and LNCaP), and a normal nonprostate line (HaCaT). Supplement toxicity was assessed using cell proliferation assays [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide] and cellular radiosensitivity using conventional clonogenic assays (0.5-4Gy). Cell cycle kinetics were assessed using the bromodeoxyuridine/propidium iodide pulse-labeling technique, apoptosis by scoring caspase-3 activation, and DNA repair by assessing gammaH2AX. Results: The cell growth and radiosensitivity of the malignant PC3, DU145, and LNcaP cells were not affected by any of the dietary prostate supplements (Provelex [2mug/mL], Trinovin [10mug/mL], and Prostate Rx [50 mug/mL]). However, both Trinovin (10mug/mL) and Prostate Rx (6mug/mL) inhibited the growth rate of the normal prostate cell lines. Prostate Rx increased cellular radiosensitivity of RWPE-1 cells through the inhibition of DNA repair. Conclusion: The use of prostate-specific dietary supplements should be discouraged during radiotherapy owing to the preferential radiosensitization of normal prostate cells.

Hasan, Yasmin; Schoenherr, Diane; Martinez, Alvaro A.; Wilson, George D. [William Beaumont Hospital, Royal Oak, MI (United States); Marples, Brian, E-mail: brian.marples@beaumont.ed [William Beaumont Hospital, Royal Oak, MI (United States)

2010-03-01

362

Dependence of 5-fluorouracil-mediated radiosensitization on DNA-directed effects  

SciTech Connect

Although 5-fluorouracil (FUra) has been demonstrated to be a radiation sensitizer both in the laboratory and the clinic, it is not known whether radiosensitization results primary from FUra's DNA or RNA-directed effects. The authors studied the radiosensitizing effects of FUra [+-] thymidine (dThd) on HT29 human colon cancer cells, which are relatively sensitive to the DNA-directed action of FUra, in comparison to SW620 and HuTu80 human colon cancer cells, which are relatively resistant to FUra's DNA-directed effects. They hypothesized that if FUra were acting chiefly through DNA dependent mechanisms, HT29 cells would (a) show greater radiosensitization than SW620 and HuTu80 cells under the same conditions of exposure; and (b) demonstrate selective reversal of radiation sensitivity (compared to cytotoxicity) in the presence of FUra + dThd, compared to FUra alone. They found that the enhancement ratio produced by a 24 h exposure to 10 [mu]M FUra was significantly greater in HT29 cells compared to SW620 and HuTu80 cells (enhancement ratios of 2.1 [+-] 0.1; 1.1 [+-] 0.1, and 1.3 [+-] 0.1, respectively). Furthermore, in HT29 cells, dThd blocked FUra-mediated radiosensitization to a greater extent than FUra-mediated cytotoxicity. Thus, the hypotheses were confirmed. These findings support the concept that the manipulation of FUra's DNA-dependent actions, for example, through modulators of thymidylate synthase (TS) activity, may increase radiosensitization in clinical trials in the treatment of gastrointestinal cancers. However, since resistance to the DNA-directed effects of fluoropyrimidines can result from mechanisms unrelated to TS inhibition, additional strategies will be required to potentiate fluoropyrimidine-mediated radiosensitization. 15 refs., 2 figs., 1 tab.

Lawrence, T.S.; Davis, M.A.; Maybaum, J. (Univ. of Michigan Medical Center, Ann Arbor, MI (United States))

1994-06-15

363

Malignant prolactinomas.  

PubMed

Six cases of malignant prolactinoma have been reported; an additional two cases are presented here and the literature is reviewed. Diagnosis rests upon evidence of metastasis rather than histological criteria per se. Cases have arisen from known adenomas, particularly the invasive type. Bromocriptine is a useful palliative. The features and treatment of malignant prolactinoma are discussed. PMID:1870674

Popovic, E A; Vattuone, J R; Siu, K H; Busmanis, I; Pullar, M J; Dowling, J

1991-07-01

364

Restoration of the expression of transports associated with antigen processing in human malignant melanoma increases tumor-specific immunity.  

PubMed

The transporter associated with antigen processing (TAP) is essential for peptide delivery from the cytos