Folic acid conjugation improves the bioavailability and chemosensitizing efficacy of curcumin-encapsulated PLGA-PEG nanoparticles towards paclitaxel chemotherapy

PubMed Central

Shankar, Mohan; Vijayakurup, Vinod; Anwar, Shabna; Thankachan, Sanu; Pillai, Kavya S.; Pillai, Jisha J.; Nandan, C. Devika; Alex, Vijai V.; Chirayil, Teena Jacob; Sundaram, Sankar; Kumar, Gopalakrishnapillai Sankaramangalam Vinod; Anto, Ruby John

2017-01-01

Nanoencapsulation has emerged as a novel strategy to enhance the pharmacokinetic and therapeutic potential of conventional drugs. Recent studies from our lab have established the efficacy of curcumin in sensitizing cervical cancer cells and breast cancer cells towards paclitaxel and 5-FU chemotherapy respectively. Factors that hinder the clinical use of curcumin as a sensitizer or therapeutic agent include its poor bioavailability and retention time. Earlier reports of improvement in bioavailability and retention of drugs upon nanoencapsulation have motivated us in developing various nanoformulations of curcumin, which were found to exhibit significant enhancement in bioavailability and retention time as assessed by our previous in vitro studies. Among the various formulations tested, curcumin-entrapped in PLGA-PEG nanoparticles conjugated to folic acid (PPF-curcumin) displayed maximum cell death. In the present study, we have demonstrated the efficacy of this formulation in augmenting the bioavailability and retention time of curcumin, in vivo, in Swiss albino mice. Further, the acute and chronic toxicity studies proved that the formulation is pharmacologically safe. We have also evaluated its potential in chemosensitizing cervical cancer cells to paclitaxel and have verified the results using cervical cancer xenograft model in NOD-SCID mice. Folic acid conjugation significantly enhanced the efficacy of curcumin in down-regulating various survival signals induced by paclitaxel in cervical cancer cells and have considerably improved its potential in inhibiting the tumor growth of cervical cancer xenografts. The non-toxic nature coupled with improved chemosensitization potential makes PPF-curcumin a promising candidate formulation for clinical trials. PMID:29296172

Ferulic acid reverses ABCB1-mediated paclitaxel resistance in MDR cell lines.

PubMed

Muthusamy, Ganesan; Balupillai, Agilan; Ramasamy, Karthikeyan; Shanmugam, Mohana; Gunaseelan, Srithar; Mary, Beaulah; Prasad, N Rajendra

2016-09-05

Multidrug resistance (MDR) remains a major obstacle in cancer chemotherapy. The use of the dietary phytochemicals as chemosensitizing agents to enhance the efficacy of conventional cytostatic drugs has recently gained the attention as a plausible approach for overcoming the drug resistance. The aim of this study was to investigate whether a naturally occurring diet-based phenolic acid, ferulic acid, could sensitize paclitaxel efficacy in ABCB1 overexpressing (P-glycoprotein) colchicine selected KB Ch(R)8-5 cell line. In vitro drug efflux assays demonstrated that ferulic acid inhibits P-glycoprotein transport function in drug resistant KB Ch(R)8-5 cell lines. However, ferulic acid significantly downregulates ABCB1 expression in a concentration dependent manner. Cytotoxicity assay reveals that ferulic acid decreased paclitaxel resistance in KBCh(R)8-5 and HEK293/ABCB1 cells, which indicates its chemosensitizing potential. Clonogenic cell survival assay and apoptotic morphological staining further confirm the chemosensitizing potential of ferulic acid in drug resistant KB Ch(R)8-5 cell lines. Ferulic acid treatment enhances paclitaxel mediated cell cycle arrest and upregulates paclitaxel-induced apoptotic signaling in KB resistant cells. Hence, it has been concluded that downregulation of ABCB1 and subsequent induction of paclitaxel-mediated cell cycle arrest and apoptotic signaling may be the cause for the chemosensitizing potential of ferulic acid in P-gp overexpressing cell lines. Copyright © 2016 Elsevier B.V. All rights reserved.

Persistent lung oscillator response to CO2 after buccal oscillator inhibition in the adult frog.

PubMed

Leclère, Renaud; Straus, Christian; Similowski, Thomas; Bodineau, Laurence; Fiamma, Marie-Noëlle

2012-08-15

The automatic ventilatory drive in amphibians depends on two oscillators interacting with each other, the gill/buccal and lung oscillators. The lung oscillator would be homologous to the mammalian pre-Bötzinger complex and the gill/buccal oscillator homologous to the mammalian parafacial respiratory group/retrotrapezoid nucleus (pFRG/RTN). Dysfunction of the pFRG/RTN has been involved in the development of respiratory diseases associated to the loss of CO(2) chemosensitivity such as the congenital central hypoventilation syndrome. Here, on adult in vitro isolated frog brainstem, consequences of the buccal oscillator inhibition (by reducing Cl(-)) were evaluated on the respiratory rhythm developed by the lung oscillator under hypercapnic challenges. Our results show that under low Cl(-) concentration (i) the buccal oscillator is strongly inhibited and the lung burst frequency and amplitude decreased and (ii) it persists a powerful CO(2) chemosensitivity. In conclusion, in frog, the CO(2) chemosensitivity depends on cellular contingent(s) whose the functioning is independent of the concentration of Cl(-) and origin remains unknown. Copyright © 2012 Elsevier B.V. All rights reserved.

TS mRNA levels can predict pemetrexed and raltitrexed sensitivity in colorectal cancer.

PubMed

Zhang, Qun; Shen, Jie; Wang, Hao; Hu, Jing; Yu, Lixia; Xie, Li; Wei, Jia; Liu, Baorui; Guan, Wenxian; Qian, Xiaoping

2014-02-01

The purpose of the study is to analyze the relationship between tumor thymidylate synthase (TS) mRNA expression levels and raltitrexed/pemetrexed/5-FU sensitivity. We collected freshly removed colorectal tumor specimens from 50 patients. Chemosensitivities to anticancer drugs were evaluated by histoculture drug response assay. We adopted quantitative reverse transcription polymerase chain reaction for TS mRNA detection and immunohistochemical staining for assessing TS expression in tumor tissues. There is a significant relationship between TS mRNA expression levels and in vitro chemosensitivity of freshly removed colorectal tumor specimens to pemetrexed (P < 0.001)/raltitrexed (P = 0.004)/5-FU (P = 0.007). TS mRNA expression levels can predict pemetrexed and raltitrexed sensitivity in colorectal cancer.

Histoculture and the immunodeficient mouse come to the cancer clinic - rational approaches to individualizing cancer-therapy and new drug-evaluation (review).

PubMed

Hoffman, R

1992-09-01

Originating from the experiments of Alexis Carrel, tissues in culture were originally grown in three dimensions and maintained important in vivo-like structural and functional properties. However, in modem times, monolayer cell culture methods have become predominant despite losses of structural and functional properties of the cells. Strangeways, Fell, Leighton, Sutherland and others have designed various methods of three-dimensional culture using cellulose supports, mesh supports, collagen gel or sponge supports and floatation that allow tissues to maintain many in vivo-like properties such as native architecture, differentiated functions, gene regulation, invasive properties and drug sensitivities which are very different than cells in monolayer cultures. Collagen-sponge-gel-supported histoculture has been shown to support the growth and native three-dimensional architecture of both tumor and normal tissue, often for long periods of time. This method of histoculture was utilized to develop a chemosensitivity assay for individual cancer patients by assessing the effects of drug on the patients' histocultured tumor. Various end points to measure drug response have been utilized in histoculture, including [H-3]thymidine incorporation measured by histological autoradiography and the use of vital dyes to indicate cell viability. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H tetrazolium bromide (MTT) end point was applied to the histoculture assay in an attempt to increase in vitro-in vivo correlation. The chemosensitivities of 16 human tumor lines were determined in vitro by the histoculture assay, and retrospectively correlated to their in vivo chemosensitivity as xenografts in nude mice. The overall correlation rate of the efficacy results of the drug-response assay to in vivo chemosensitivities was 89.8%, with 90.0% true-positive and 89.7% true-negative rates, 81.7% sensitivity and 94.6% specificity, thereby indicating potential clinical use for tumor histoculture with the MTT end point. The data reviewed and analyzed here thus indicate that three-dimensional culture systems offer much more realistic model systems for evaluating potential new cancer agents and individualized treatment such as predictive drug-response testing. The 'MetaMouse' model developed in our laboratory allows direct 'onplantation' of intact patient surgical cancer specimens orthotopically to athymic 'nude' mice with high-level expression of local growth on the target organ and high metastatic potential. Eight MetaMouse human cancer models are reviewed including those for the colon, bladder, lung, stomach, prostate, ovary, pancreas and head and neck. The human tumors growing and metastasizing in the mice reflect the clinical situation and should be useful for new drug evaluation and development of strategies for individual treatment. The combined technologies of histoculture and MetaMouse thus offer an integrated in vitro-in vivo system for preclinical evaluation of experimental and standard cancer therapy.

Novel prediction of anticancer drug chemosensitivity in cancer cell lines: evidence of moderation by microRNA expressions.

PubMed

Yang, Daniel S

2014-01-01

The objectives of this study are (1) to develop a novel "moderation" model of drug chemosensitivity and (2) to investigate if miRNA expression moderates the relationship between gene expression and drug chemosensitivity, specifically for HSP90 inhibitors applied to human cancer cell lines. A moderation model integrating the interaction between miRNA and gene expressions was developed to examine if miRNA expression affects the strength of the relationship between gene expression and chemosensitivity. Comprehensive datasets on miRNA expressions, gene expressions, and drug chemosensitivities were obtained from National Cancer Institute's NCI-60 cell lines including nine different cancer types. A workflow including steps of selecting genes, miRNAs, and compounds, correlating gene expression with chemosensitivity, and performing multivariate analysis was utilized to test the proposed model. The proposed moderation model identified 12 significantly-moderating miRNAs: miR-15b*, miR-16-2*, miR-9, miR-126*, miR-129*, miR-138, miR-519e*, miR-624*, miR-26b, miR-30e*, miR-32, and miR-196a, as well as two genes ERCC2 and SF3B1 which affect chemosensitivities of Tanespimycin and Alvespimycin - both HSP90 inhibitors. A bootstrap resampling of 2,500 times validates the significance of all 12 identified miRNAs. The results confirm that certain miRNA and gene expressions interact to produce an effect on drug response. The lack of correlation between miRNA and gene expression themselves suggests that miRNA transmits its effect through translation inhibition/control rather than mRNA degradation. The results suggest that miRNAs could serve not only as prognostic biomarkers for cancer treatment outcome but also as interventional agents to modulate desired chemosensitivity.

Central chemosensitivity is augmented during 2 h of thermoneutral head-out water immersion in healthy men and women.

PubMed

Sackett, James R; Schlader, Zachary J; O'Leary, Morgan C; Chapman, Christopher L; Johnson, Blair D

2018-05-01

What is the central question of the study? Is central chemosensitivity blunted during thermoneutral head-out water immersion in healthy humans? What is the main finding and its importance? Central chemosensitivity is augmented during thermoneutral head-out water immersion in healthy men and women. Thus, we suggest that the central chemoreceptors do not contribute to CO 2 retention during head-out water immersion. Carbon dioxide retention occurs during water immersion. Therefore, we tested the hypothesis that central chemosensitivity to hypercapnia is blunted during 2 h of thermoneutral head-out water immersion (HOWI) in healthy young adults. Twenty-six participants (age 22 ± 2 years; body mass index 24 ± 3 kg m -2 ; 14 women) participated in two experimental visits: a HOWI visit (HOWI) and a dry time-control visit (Control). Central chemosensitivity was assessed via a rebreathing test at baseline, 10, 60, 90 and 120 min and after HOWI and Control. End-tidal CO 2 tension (P ET ,CO2), minute ventilation, blood pressure and heart rate were recorded continuously. The P ET ,CO2 increased from baseline throughout HOWI (peak increase at 120 min 2 ± 2 mmHg; P < 0.001), and the change in P ET ,CO2 was greater throughout HOWI than Control (P < 0.001). The change in minute and alveolar ventilation was not different throughout time (P ≥ 0.173) or between conditions (P ≥ 0.052). Central chemosensitivity was greater than at baseline throughout HOWI (peak increase 0.74 ± 1.01 l min -1  mmHg -1 at 120 min; P < 0.001), and the change in central chemosensitivity was greater throughout HOWI than Control (P  ≤  0.006). We also divided the cohort into tertiles based on baseline central chemosensitivity (i.e. Low, Intermediate and High) and compared Low versus High during HOWI. Low demonstrated an increase in P ET ,CO2 starting at 10 min (2 ± 3 mmHg; P < 0.001), whereas High did not exhibit an increase in P ET ,CO2 until 60 min (2 ± 2 mmHg; P = 0.018). These data indicate that CO 2 retention occurs throughout HOWI despite augmented central chemosensitivity and that having a high baseline central chemosensitivity might delay the onset of CO 2 retention. © 2018 The Authors. Experimental Physiology © 2018 The Physiological Society.

Quercetin and doxorubicin co-encapsulated biotin receptor-targeting nanoparticles for minimizing drug resistance in breast cancer.

PubMed

Lv, Li; Liu, Chunxia; Chen, Chuxiong; Yu, Xiaoxia; Chen, Guanghui; Shi, Yonghui; Qin, Fengchao; Ou, Jiebin; Qiu, Kaifeng; Li, Guocheng

2016-05-31

The combination of a chemotherapeutic drug with a chemosensitizer has emerged as a promising strategy for cancers showing multidrug resistance (MDR). Herein we describe the simultaneous targeted delivery of two drugs to tumor cells by using biotin-decorated poly(ethylene glycol)-b-poly(ε-caprolactone) nanoparticles encapsulating the chemotherapeutic drug doxorubicin and the chemosensitizer quercetin (BNDQ). Next, the potential ability of BNDQ to reverse MDR in vitro and in vivo was investigated. Studies demonstrated that BNDQ was more effectively taken up with less efflux by doxorubicin-resistant MCF-7 breast cancer cells (MCF-7/ADR cells) than by the cells treated with the free drugs, single-drug-loaded nanoparticles, or non-biotin-decorated nanoparticles. BNDQ exhibited clear inhibition of both the activity and expression of P-glycoprotein in MCF-7/ADR cells. More importantly, it caused a significant reduction in doxorubicin resistance in MCF-7/ADR breast cancer cells both in vitro and in vivo, among all the groups. Overall, this study suggests that BNDQ has a potential role in the treatment of drug-resistant breast cancer.

Overexpression of Hiwi Inhibits the Cell Growth of Chronic Myeloid Leukemia K562 Cells and Enhances Their Chemosensitivity to Daunomycin.

PubMed

Wang, Yalin; Jiang, Yan; Bian, Cuicui; Dong, Yi; Ma, Chao; Hu, Xiaolin; Liu, Ziling

2015-09-01

Chronic myeloid leukemia (CML) is a clonal disorder characterized by excessive accumulation of myeloid cells in the peripheral blood. In the present study, to investigate the role of Hiwi in leukemogenesis, lentivirus-mediated Hiwi overexpression was performed in a CML cell line, K562 cells. Our data revealed that Hiwi protein expression was undetectable in K562 cells, and its overexpression suppressed cell proliferation, induced cell cycle arrest at G0/G1 and G2/M phases, and promoted apoptosis in K562 cells in vitro. Expression of anti-apoptotic protein, Bcl-2, was decreased in cells expressing Hiwi, whereas that of pro-apoptotic proteins, Bax, activated caspase-3, -9, and cleaved poly (ADP-ribose) polymerase were increased. Additionally, Hiwi upregulation enhanced the chemosensitivity of CML cells to daunomycin. Our study illustrates that expression deletion of Hiwi may be involved in the pathogenesis of human CML and suggests a possible role of Hiwi in regulating the cell growth, cell cycle, and apoptosis of CML cells in vitro.

Multi-Targeted Agents in Cancer Cell Chemosensitization: What We Learnt from Curcumin Thus Far.

PubMed

Bordoloi, Devivasha; Roy, Nand K; Monisha, Javadi; Padmavathi, Ganesan; Kunnumakkara, Ajaikumar B

2016-01-01

Research over the past several years has developed many mono-targeted therapies for the prevention and treatment of cancer, but it still remains one of the fatal diseases in the world killing 8.2 million people annually. It has been well-established that development of chemoresistance in cancer cells against mono-targeted chemotherapeutic agents by modulation of multiple survival pathways is the major cause of failure of cancer chemotherapy. Therefore, inhibition of these pathways by non-toxic multi-targeted agents may have profoundly high potential in preventing drug resistance and sensitizing cancer cells to chemotherapeutic agents. To study the potential of curcumin, a multi-targeted natural compound, obtained from the plant Turmeric (Curcuma longa) in combination with standard chemotherapeutic agents to inhibit drug resistance and sensitize cancer cells to these agents based on available literature and patents. An extensive literature survey was performed in PubMed and Google for the chemosensitizing potential of curcumin in different cancers published so far and the patents published during 2014-2015. Our search resulted in many in vitro, in vivo and clinical reports signifying the chemosensitizing potential of curcumin in diverse cancers. There were 160 in vitro studies, 62 in vivo studies and 5 clinical studies. Moreover, 11 studies reported on hybrid curcumin: the next generation of curcumin based therapeutics. Also, 34 patents on curcumin's biological activity have been retrieved. Altogether, the present study reveals the enormous potential of curcumin, a natural, non-toxic, multi-targeted agent in overcoming drug resistance in cancer cells and sensitizing them to chemotherapeutic drugs.

The disruption of central CO2 chemosensitivity in a mouse model of Rett syndrome

PubMed Central

Zhang, Xiaoli; Su, Junda; Cui, Ningren; Gai, Hongyu; Wu, Zhongying

2011-01-01

People with Rett syndrome (RTT) have breathing instability in addition to other neuropathological manifestations. The breathing disturbances contribute to the high incidence of unexplained death and abnormal brain development. However, the cellular mechanisms underlying the breathing abnormalities remain unclear. To test the hypothesis that the central CO2 chemoreception in these people is disrupted, we studied the CO2 chemosensitivity in a mouse model of RTT. The Mecp2-null mice showed a selective loss of their respiratory response to 1–3% CO2 (mild hypercapnia), whereas they displayed more regular breathing in response to 6–9% CO2 (severe hypercapnia). The defect was alleviated with the NE uptake blocker desipramine (10 mg·kg−1·day−1 ip, for 5–7 days). Consistent with the in vivo observations, in vitro studies in brain slices indicated that CO2 chemosensitivity of locus coeruleus (LC) neurons was impaired in Mecp2-null mice. Two major neuronal pH-sensitive Kir currents that resembled homomeric Kir4.1 and heteromeric Ki4.1/Kir5.1 channels were identified in the LC neurons. The screening of Kir channels with real-time PCR indicated the overexpression of Kir4.1 in the LC region of Mecp2-null mice. In a heterologous expression system, an overexpression of Kir4.1 resulted in a reduction in the pH sensitivity of the heteromeric Kir4.1-Kir5.1 channels. Given that Kir4.1 and Kir5.1 subunits are also expressed in brain stem respiration-related areas, the Kir4.1 overexpression may not allow CO2 to be detected until hypercapnia becomes severe, leading to periodical hyper- and hypoventilation in Mecp2-null mice and, perhaps, in people with RTT as well. PMID:21307341

Smad4 sensitizes colorectal cancer to 5-fluorouracil through cell cycle arrest by inhibiting the PI3K/Akt/CDC2/survivin cascade.

PubMed

Zhang, Binhao; Leng, Chao; Wu, Chao; Zhang, Zhanguo; Dou, Lei; Luo, Xin; Zhang, Bixiang; Chen, Xiaoping

2016-03-01

5-Fluorouracil (5-FU), a cell cycle-specific antimetabolite, is one of the most commonly used chemotherapeutic agents for colorectal cancer (CRC). Yet, resistance to 5-FU-based chemotherapy is still an obstacle to the treatment of this malignancy. Mutation or loss of Smad4 in CRC is pivotal for chemoresistance. However, the mechanism by which Smad4 regulates the chemosensitivity of CRC remains unclear. In the present study, we investigated the role of Smad4 in the chemosensitivity of CRC to 5-FU, and whether Smad4-regulated cell cycle arrest is involved in 5-FU chemoresistance. We used Smad4-expressing CT26 and Smad4-null SW620 cell lines as experimental models, by knockdown or transgenic overexpression. Cells or tumors were treated with 5-FU to determine chemosensitivity by cell growth, tumorigenicity assay and a mouse model. Cell cycle distribution was examined with flow cytometric analysis, and cell cycle-related proteins were examined by western blotting. Smad4 deficiency in CT26 and SW620 cells induced chemoresistance to 5-FU both in vitro and in vivo. Smad4 deficiency attenuated G1 or G2 cell cycle arrest by activating the PI3K/Akt/CDC2/survivin pathway. The PI3K inhibitor, LY294002, reversed the activation of the Akt/CDC2/survivin cascade in the Smad4-deficient cells, while it had little effect on cells with high Smad4 expression. In conclusion, we discovered a novel mechanism mediated by Smad4 to trigger 5-FU chemosensitivity through cell cycle arrest by inhibiting the PI3K/Akt/CDC2/survivin cascade. The present study also implies that LY294002 has potential therapeutic value to reverse the chemosensitivity of CRC with low Smad4 expression.

In vitro characterization of noradrenergic modulation of chemosensitive neurons in the retrotrapezoid nucleus

PubMed Central

Kuo, Fu-Shan; Falquetto, Bárbara; Chen, Dawei; Oliveira, Luiz M.; Takakura, Ana C.

2016-01-01

Chemosensitive neurons in the retrotrapezoid nucleus (RTN) regulate breathing in response to CO2/H+ changes and serve as an integration center for other autonomic centers, including brain stem noradrenergic neurons. Norepinephrine (NE) contributes to respiratory control and chemoreception, and, since disruption of NE signaling may contribute to several breathing disorders, we sought to characterize effects of NE on RTN chemoreception. All neurons included in this study responded similarly to CO2/H+ but showed differential sensitivity to NE; we found that NE activated (79%), inhibited (7%), or had no effect on activity (14%) of RTN chemoreceptors. The excitatory effect of NE on RTN chemoreceptors was dose dependent, retained in the presence of neurotransmitter receptor blockers, and could be mimicked and blocked by pharmacological manipulation of α1-adrenergic receptors (ARs). In addition, NE-activation was blunted by XE991 (KCNQ channel blocker), and partially occluded the firing response to serotonin, suggesting involvement of KCNQ channels. However, in whole cell voltage clamp, activation of α1-ARs decreased outward current and conductance by what appears to be a mixed effect on multiple channels. The inhibitory effect of NE on RTN chemoreceptors was blunted by an α2-AR antagonist. A third group of RTN chemoreceptors was insensitive to NE. We also found that chemosensitive RTN astrocytes do not respond to NE with a change in voltage or by releasing ATP to enhance activity of chemosensitive neurons. These results indicate NE modulates subsets of RTN chemoreceptors by mechanisms involving α1- and α2-ARs. PMID:27306669

Inhibition of p70S6K1 activation by Pdcd4 overcomes the resistance to an IGF-1R/IR inhibitor in colon carcinoma cells

PubMed Central

Zhang, Yan; Wang, Qing; Chen, Li; Yang, Hsin-Sheng

2015-01-01

Agents targeting insulin-like growth factor 1 receptor (IGF-1R) are being actively examined in clinical trials. Although there has been some initial success of single agent targeting IGF-1R, attempts in later studies failed due to resistance. This study aimed to understand the effects of programmed cell death 4 (Pdcd4) on the chemosensitivity of the IGF-1R inhibitor, OSI-906, in colorectal cancer (CRC) cells and the mechanism underlying this impact. Using OSI-906 resistant and sensitive CRC cells, we found that the Pdcd4 level directly correlates with cell chemosensitivity to OSI-906. In addition, tumors derived from Pdcd4 knockdown cells resist the growth inhibitory effect of OSI-906 in a CRC xenograft mouse model. Moreover, Pdcd4 enhances the antiproliferative effect of OSI-906 in resistant cells through suppression of p70S6K1 activation. Knockdown of p70S6K1, but not p70S6K2, significantly increases the chemosensitivity of OSI-906 in cultured CRC cells. Furthermore, the combination of OSI-906 and PF4708671, a p70S6K1 inhibitor, efficiently suppresses the growth of OSI-906 resistant colon tumor cells in vitro and in vivo. Taken together, activation of p70S6K1 that is inhibited by Pdcd4 is essential for resistance to IGF-1R inhibitor in colon tumor cells, and the combinational treatment of OSI-906 and PF-4708671 results in enhanced antiproliferation effects in CRC cells in vitro and in vivo, providing a novel venue to overcome the resistance to IGF-1R inhibitor in treating colorectal cancer. PMID:25573956

Zinc enhances temozolomide cytotoxicity in glioblastoma multiforme model systems

PubMed Central

Toren, Amos; Pismenyuk, Tatyana; Yalon, Michal; Freedman, Shani; Simon, Amos J.; Fisher, Tamar; Moshe, Itai; Reichardt, Juergen K.V.; Constantini, Shlomi; Mardor, Yael; Last, David; Guez, David; Daniels, Dianne; Assoulin, Moria; Mehrian-Shai, Ruty

2016-01-01

Temozolomide (TMZ) is an alkylating agent that has become the mainstay treatment of the most malignant brain cancer, glioblastoma multiforme (GBM). Unfortunately only a limited number of patients positively respond to it. It has been shown that zinc metal reestablishes chemosensitivity but this effect has not been tested with TMZ. Using both in vitro and in vivo experimental approaches, we investigated whether addition of zinc to TMZ enhances its cytotoxicity against GBM. In vitro cell viability analysis showed that the cytotoxic activity of TMZ was substantially increased with addition of zinc and this response was accompanied by an elevation of p21, PUMA, BAX and Caspase-3 expression and a decrease in growth fraction as manifested by low ki67 and lower colony formation. Analysis of GBM as intracranial xenografts in athymic mice and administration of concurrent TMZ and zinc yielded results consistent with those of the in vitro analyses. The co-treatment resulted in significant reduction in tumor volume in TMZ/zinc treated mice relative to treatment with TMZ alone. Our results suggest that zinc may serve as a potentiator of TMZ therapy in GBM patients. PMID:27556862

In vitro and in vivo activity of LS 4477 and LS 4559, novel analogues of the tubulin binder estramustine.

PubMed

Nicholson, K M; Phillips, R M; Shnyder, S D; Bibby, M C

2002-01-01

LS 4477 and LS 4559, two of a series of N-acyl-aminoalkyl phenyl ethers, are rationally designed compounds based on the tubulin binder estramustine. This study investigated their mechanism of action and compared their effectiveness in relation to estramustine in vitro against a panel of human and murine cell lines and in vivo against two murine colon tumour models (MAC). At biologically relevant concentrations, LS 4477 and LS 4559 caused a 59.9 and 56% reduction in tubulin assembly, respectively, compared with a 28.4% reduction in tubulin assembly by estramustine. The analogues were approximately 100 times more potent in chemosensitivity tests in vitro than the parent compound. Both analogues were orally active against the MAC 15A murine tumour model, to a greater extent than estramustine, producing significant growth delays (P<0.01). Significant activity was also shown against the slower growing MAC 26 tumour for LS 4577 (the soluble pro-drug of LS 4559). The results presented in this study suggest these compounds warrant further development with a view to assessing their clinical activity.

Zinc enhances temozolomide cytotoxicity in glioblastoma multiforme model systems.

PubMed

Toren, Amos; Pismenyuk, Tatyana; Yalon, Michal; Freedman, Shani; Simon, Amos J; Fisher, Tamar; Moshe, Itai; Reichardt, Juergen K V; Constantini, Shlomi; Mardor, Yael; Last, David; Guez, David; Daniels, Dianne; Assoulin, Moria; Mehrian-Shai, Ruty

2016-11-15

Temozolomide (TMZ) is an alkylating agent that has become the mainstay treatment of the most malignant brain cancer, glioblastoma multiforme (GBM). Unfortunately only a limited number of patients positively respond to it. It has been shown that zinc metal reestablishes chemosensitivity but this effect has not been tested with TMZ. Using both in vitro and in vivo experimental approaches, we investigated whether addition of zinc to TMZ enhances its cytotoxicity against GBM. In vitro cell viability analysis showed that the cytotoxic activity of TMZ was substantially increased with addition of zinc and this response was accompanied by an elevation of p21, PUMA, BAX and Caspase-3 expression and a decrease in growth fraction as manifested by low ki67 and lower colony formation. Analysis of GBM as intracranial xenografts in athymic mice and administration of concurrent TMZ and zinc yielded results consistent with those of the in vitro analyses. The co-treatment resulted in significant reduction in tumor volume in TMZ/zinc treated mice relative to treatment with TMZ alone. Our results suggest that zinc may serve as a potentiator of TMZ therapy in GBM patients.

Marine drug Haishengsu increases chemosensitivity to conventional chemotherapy and improves quality of life in patients with acute leukemia.

PubMed

Li, Guang-Yao; Zhang, Li; Liu, Ji-Zhu; Chen, Shou-Guo; Xiao, Tai-Wu; Liu, Guo-Zhen; Wang, Jing-Xia; Wang, Le-Xin; Hou, Ming

2016-07-01

Pharmacological management of acute leukemia remains a challenge. A seashell protein Haishengsu (HSS) has been found to exert anticancer activities in recent in vitro studies. The aim of this study was to determine whether the addition of HSS to the conventional chemotherapies would increase chemosensitivity and improves quality of life in patients with acute leukemia. Two hundred and forty-eight patients with acute leukemia were enrolled in a double-blind, and placebo-controlled study. In addition to conventional chemotherapy, 142 patients received HSS and 106 received placebo. In an in vitro study, the expression of P-gp was evaluated by flow cytometry in a drug-resistant leukemia cell line (K562/ADM cells). Sorcin was examined by Western blot. The complete remission rates in the HSS treatment group were all higher than in the placebo group with non-relapsing leukemia and relapsed leukemia (p<0.05). Less patients in the HSS group experienced gastrointestinal side effects from chemotherapy, whereas more patients had increased food take and an increase in Karnofsky performance status (KPS) score (p<0.01). In vitro, the expression of P-gp and sorcin in the HSS treated cells were lower than in the control group cells (p<0.01). When added to conventional chemotherapy, HSS improves the complete remission rates and quality of life in patients with acute leukemia. The in vitro findings indicate that suppression of P-gp and sorcin genes in leukemia cells may be involved in the beneficial effects of HSS. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Acid-sensing ion channels contribute to chemosensitivity of breathing-related neurons of the nucleus of the solitary tract.

PubMed

Huda, Rafiq; Pollema-Mays, Sarah L; Chang, Zheng; Alheid, George F; McCrimmon, Donald R; Martina, Marco

2012-10-01

Cellular mechanisms of central pH chemosensitivity remain largely unknown. The nucleus of the solitary tract (NTS) integrates peripheral afferents with central pathways controlling breathing; NTS neurons function as central chemosensors, but only limited information exists concerning the ionic mechanisms involved. Acid-sensing ion channels (ASICs) mediate chemosensitivity in nociceptive terminals, where pH values ∼6.5 are not uncommon in inflammation, but are also abundantly expressed throughout the brain where pHi s tightly regulated and their role is less clear. Here we test the hypothesis that ASICs are expressed in NTS neurons and contribute to intrinsic chemosensitivity and control of breathing. In electrophysiological recordings from acute rat NTS slices, ∼40% of NTS neurons responded to physiological acidification (pH 7.0) with a transient depolarization. This response was also present in dissociated neurons suggesting an intrinsic mechanism. In voltage clamp recordings in slices, a pH drop from 7.4 to 7.0 induced ASIC-like inward currents (blocked by 100 μM amiloride) in ∼40% of NTS neurons, while at pH ≤ 6.5 these currents were detected in all neurons tested; RT-PCR revealed expression of ASIC1 and, less abundantly, ASIC2 in the NTS. Anatomical analysis of dye-filled neurons showed that ASIC-dependent chemosensitive cells (cells responding to pH 7.0) cluster dorsally in the NTS. Using in vivo retrograde labelling from the ventral respiratory column, 90% (9/10) of the labelled neurons showed an ASIC-like response to pH 7.0, suggesting that ASIC currents contribute to control of breathing. Accordingly, amiloride injection into the NTS reduced phrenic nerve activity of anaesthetized rats with an elevated arterial P(CO(2)) .

Chemo-sensitivity in a panel of B-cell precursor acute lymphoblastic leukemia cell lines, YCUB series, derived from children.

PubMed

Goto, Hiroaki; Naruto, Takuya; Tanoshima, Reo; Kato, Hiromi; Yokosuka, Tomoko; Yanagimachi, Masakatsu; Fujii, Hisaki; Yokota, Shumpei; Komine, Hiromi

2009-10-01

Sensitivity to 10 anticancer drugs was evaluated in 6 childhood B-cell precursor acute lymphoblastic leukemia (BCP-ALL) cell lines. Authenticity of newly established cell lines was confirmed by genomic fingerprinting. The line YCUB-5R established at relapse was more resistant to 4-hydroperoxy-cyclophosphamide, cytarabine, L-asparaginase, topotecan, fludarabine, and etoposide than YCUB-5 from the same patient at diagnosis. Of the drugs tested, etoposide and SN-38 (irinotecan) showed highest efficacy in the panel, with 50% growth inhibition at 0.22-1.8 microg/ml and 0.57-3.6 ng/ml, respectively. This cell line panel offers an in vitro model for the development of new therapies for childhood BCP-ALL.

A Targeted RNAi Screen of the Breast Cancer Genome Identifies KIF14 and TLN1 as Genes That Modulate Docetaxel Chemosensitivity in Triple-Negative Breast Cancer

PubMed Central

Singel, Stina Mui; Cornelius, Crystal; Batten, Kimberly; Fasciani, Gail; Wright, Woodring E.; Lum, Lawrence; Shay, Jerry W.

2015-01-01

Purpose To identify biomarkers within the breast cancer genome that may predict chemosensitivity in breast cancer. Experimental Design We conducted an RNA interference (RNAi) screen within the breast cancer genome for genes whose loss-of-function enhanced docetaxel chemosensitivity in an estrogen receptor–negative, progesterone receptor–negative, and Her2-negative (ER−, PR−, and Her2−, respectively) breast cancer cell line, MDA-MB-231. Top candidates were tested for their ability to modulate chemosensitivity in 8 breast cancer cell lines and to show in vivo chemosensitivity in a mouse xenograft model. Results From ranking chemosensitivity of 328 short hairpin RNA (shRNA) MDA-MB-231 cell lines (targeting 133 genes with known somatic mutations in breast cancer), we focused on the top two genes, kinesin family member 14 (KIF14) and talin 1 (TLN1). KIF14 and TLN1 loss-of-function significantly enhanced chemosensitivity in four triple-negative breast cancer (TNBC) cell lines (MDA-MB-231, HCC38, HCC1937, and Hs478T) but not in three hormone receptor–positive cell lines (MCF7, T47D, and HCC1428) or normal human mammary epithelial cells (HMEC). Decreased expression of KIF14, but not TLN1, also enhanced docetaxel sensitivity in a Her2-amplified breast cancer cell line, SUM190PT. Higher KIF14 and TLN1 expressions are found in TNBCs compared with the other clinical subtypes. Mammary fat pad xenografts of KIF14- and TLN1-deficient MDA-MB-231 cells revealed reduced tumor mass compared with control MDA-MB-231 cells after chemotherapy. KIF14 expression is also prognostic of relapse-free and overall survival in representative breast cancer expression arrays. Conclusion KIF14 and TLN1 are modulators of response to docetaxel and potential therapeutic targets in TNBC. PMID:23479679

Pharyngeal chemosensitivity in patients with obstructive sleep apnea and healthy subjects.

PubMed

Heiser, Clemens; Zimmermann, Ingo; Sommer, J Ulrich; Hörmann, Karl; Herr, Raphael M; Stuck, Boris A

2013-09-01

Signs of pharyngeal neurodegeneration have been detected in patients with obstructive sleep apnea (OSA). Along with this neurodegeneration, a decreased pharyngeal sensitivity to mechanical stimulation has been described. The decreased sensitivity may play a role in the pathophysiology of this disease. The aim of the study was to investigate the chemosensitivity of the pharyngeal mucosa in patients with OSA compared with controls. Healthy controls and patients with OSA (age: 30-60 years) were included. Testing of oropharyngeal chemosensitivity was performed with subjective intensity ratings of capsaicin (SIR, visual analogue scale 0-10), air puffs (presented with an olfactometer), and stimulation with CO2 at the posterior pharyngeal wall. A 2-point discrimination test at the soft palate, an intensity rating of capsaicin at the tongue, and a nasal lateralization test were performed. Twenty-six patients with OSA and 18 healthy controls were included. No differences were detected in the SIR of capsaicin at the tongue or in the nasal lateralization test. At the pharynx, a decreased sensitivity to capsaicin (OSA: 6.8 ± 2.3; healthy control: 8.6 ± 1.3), air puffs (OSA: 2.8 ± 1.9; healthy control: 4.2 ± 1.6), and stimulation with CO2 (OSA: 1.5 ± 1.7; healthy control: 2.8 ± 1.8) were demonstrated in patients with OSA (all P < 0.05). Two-point discrimination at the soft palate was reduced with statistical significance in the OSA group (OSA: 11.5 ± 5.4 mm; healthy control: 5.0 ± 2.4 mm). The results suggest reduced pharyngeal chemosensitivity in OSA patients in addition to the reduced mechanical pharyngeal sensitivity shown with 2-point discrimination. This demonstrates peripheral neurodegeneration in the context of this disease.

Thymoquinone Augments Cisplatin-Induced Apoptosis on Esophageal Carcinoma Through Mitigating the Activation of JAK2/STAT3 Pathway.

PubMed

Hu, Xue; Ma, Jingjing; Vikash, Vikash; Li, Jiao; Wu, Dandan; Liu, Ya; Zhang, Jixiang; Dong, Weiguo

2018-01-01

Thymoquinone (TQ) is the major constituent of Nigella sativa seed and has shown biological activity in various human carcinomas. However, few studies have reported its effect on esophageal carcinoma (EC). To explore the chemosensitive effect and mechanism of TQ in augmentation of cisplatin (DDP)-induced apoptosis of EC, both in vitro and in vivo. The viability and apoptosis of esophageal carcinoma cells were detected by the Cell Counting Kit-8 assay, flow cytometry, and Hoechst 33258 staining. The expression levels of JAK2, p-JAK2, STAT3, p-STAT3, Bax, Bcl-2, Cyclin D1, Survivin, and caspase-3, 7, 9 were evaluated by western blot analysis. The histological changes were examined by TUNEL technique and immunohistochemical analysis. TQ enhanced the proapoptotic effect of DDP in human esophageal carcinoma cell line Eca-109, while blocking the activation of JAK2/STAT3 signaling pathway. The apoptosis of esophageal carcinoma cells was induced via blocking the activation of JAK2/STAT3 by using a molecular inhibitor (WP1066). Consistent with the in vivo and in vitro results, TQ increased cellular apoptosis and enriched the chemosensitivity of DDP. TQ along with DDP may regulate the progression of EC and has potential to be a chemotherapeutic agent in EC.

Preclinical studies in support of defibrotide for the treatment of multiple myeloma and other neoplasias.

PubMed

Mitsiades, Constantine S; Rouleau, Cecile; Echart, Cinara; Menon, Krishna; Teicher, Beverly; Distaso, Maria; Palumbo, Antonio; Boccadoro, Mario; Anderson, Kenneth C; Iacobelli, Massimo; Richardson, Paul G

2009-02-15

Defibrotide, an orally bioavailable polydisperse oligonucleotide, has promising activity in hepatic veno-occlusive disease, a stem cell transplantation-related toxicity characterized by microangiopathy. The antithrombotic properties of defibrotide and its minimal hemorrhagic risk could serve for treatment of cancer-associated thrombotic complications. Given its cytoprotective effect on endothelium, we investigated whether defibrotide protects tumor cells from cytotoxic antitumor agents. Further, given its antiadhesive properties, we evaluated whether defibrotide modulates the protection conferred to multiple myeloma cells by bone marrow stromal cells. Defibrotide lacks significant single-agent in vitro cytotoxicity on multiple myeloma or solid tumor cells and does not attenuate their in vitro response to dexamethasone, bortezomib, immunomodulatory thalidomide derivatives, and conventional chemotherapeutics, including melphalan and cyclophosphamide. Importantly, defibrotide enhances in vivo chemosensitivity of multiple myeloma and mammary carcinoma xenografts in animal models. In cocultures of multiple myeloma cells with bone marrow stromal cells in vitro, defibrotide enhances the multiple myeloma cell sensitivity to melphalan and dexamethasone, and decreases multiple myeloma-bone marrow stromal cell adhesion and its sequelae, including nuclear factor-kappaB activation in multiple myeloma and bone marrow stromal cells, and associated cytokine production. Moreover, defibrotide inhibits expression and/or function of key mediators of multiple myeloma interaction with bone marrow stromal cell and endothelium, including heparanase, angiogenic cytokines, and adhesion molecules. Defibrotide's in vivo chemosensitizing properties and lack of direct in vitro activity against tumor cells suggest that it favorably modulates antitumor interactions between bone marrow stromal cells and endothelia in the tumor microenvironment. These data support clinical studies of defibrotide in combination with conventional and novel therapies to potentially improve patient outcome in multiple myeloma and other malignancies.

Preclinical Studies in Support of Defibrotide for the Treatment of Multiple Myeloma and Other Neoplasias

PubMed Central

Mitsiades, Constantine S.; Rouleau, Cecile; Echart, Cinara; Menon, Krishna; Teicher, Beverly; Distaso, Maria; Palumbo, Antonio; Boccadoro, Mario; Anderson, Kenneth C.; Iacobelli, Massimo; Richardson, Paul G.

2015-01-01

Purpose of the study Defibrotide (DF), an orally bioavailable polydisperse oligonucleotide has promising activity in hepatic veno-occlusive disease (VOD), a stem cell transplantation-related toxicity, characterized by microangiopathy. The anti-thrombotic properties of DF and its minimal hemorrhagic risk could serve for treatment of cancer-associated thrombotic complications. Given its cytoprotective effect on endothelium, we investigated whether DF protects tumor cells from cytotoxic anti-tumor agents. Further, given its anti-adhesive properties, we evaluated whether DF modulates the protection conferred to multiple myeloma (MM) cells by bone marrow stromal cells (BMSCs). Methods-Results DF lacks significant single-agent in vitro cytotoxicity on MM or solid tumor cells and does not attenuate their in vitro response to dexamethasone, bortezomib, immunomodulatory thalidomide derivatives, and conventional chemotherapeutics, including melphalan and cyclophosphamide. Importantly, DF enhances in vivo chemosensitivity of MM and mammary carcinoma xenografts in animal models. In co-cultures of MM cells with BMSCs in vitro, DF enhances the MM cell sensitivity to melphalan and dexamethasone, decreases MM-BMSC adhesion and its sequelae, including NF-κB activation in MM and BMSCs, and associated cytokine production. Moreover, DF inhibits expression and/or function of key mediators of MM interaction with BMSC and endothelium, including heparanase, angiogenic cytokines and adhesion molecules. Conclusion Defibrotide’s in vivo chemosensitizing properties and lack of direct in vitro activity against tumor cells suggest that it favorably modulates antitumor interactions between BMSC and endothelia in the tumor microenvironment. These data support clinical studies of DF in combination with conventional and novel therapies to potentially improve patient outcome in MM and other malignancies. PMID:19228727

Antitumor and chemosensitizing action of 3-bromopyruvate: Implication of deregulated metabolism.

PubMed

Yadav, Saveg; Pandey, Shrish Kumar; Kumar, Ajay; Kujur, Praveen Kumar; Singh, Rana Pratap; Singh, Sukh Mahendra

2017-05-25

3-Bromopyruvate (3-BP), brominated derivative of pyruvate, possesses strong antitumor potential, owing to its ability to inhibit multiple target molecules crucial for survival of neoplastic cells. Although, 3-BP displays cytotoxicity against a wide variety of tumors, there is no report with respect to malignancies of thymic origin. Therefore, we investigated its antineoplastic action in vitro against tumor cells of a murine transplantable lymphoma of thymoma origin, designated as Dalton's lymphoma (DL). 3-BP treatment of tumor cells inhibited metabolism and survival with augmented induction of apoptosis and necrosis. 3-BP treatment suppressed lactate release, glucose uptake, deregulated pH homeostasis and augmented chemosensitization. It also altered expression of metabolism, chemosensitivity and cell survival regulatory molecules including HK 2, GAPDH, LDH, SDH, HIF-1α, MDR-1 & GLUT-1 and cytokine repertoire of IFN-γ, IL-6, IL-10, & VEGF. Pretreatment with MCT-1 inhibitor α-cyano-4-hydroxycinnamate and siRNA gene silencing of HK 2 implicated the role of MCT-1 and HK 2 in 3-BP cytotoxicity. 3-BP also altered expression of cell death regulatory Bcl-2, Mcl-1, caspase-3 accompanied by increased cytochrome c release, indicating mitochondrial mode of cell death. The study collates possible molecular mechanisms of cytotoxic action of 3-BP, which will help to optimize the therapeutic efficacy of 3-BP against tumors of thymic origin. Copyright © 2017 Elsevier B.V. All rights reserved.

An endogenous and ectopic expression of metabotropic glutamate receptor 8 (mGluR8) inhibits proliferation and increases chemosensitivity of human neuroblastoma and glioma cells.

PubMed

Jantas, Danuta; Grygier, Beata; Gołda, Sławomir; Chwastek, Jakub; Zatorska, Justyna; Tertil, Magdalena

2018-06-06

The present study aimed to determine the role of metabotropic glutamate receptor 8 (mGluR8) in tumor biology. Using various molecular approaches (RNAi or GRM8 cDNA), cell clones with downregulated (human neuroblastoma SH-SY5Y and human glioma LN229) or overexpressed (human glioma U87-MG and LN18 cell lines) mGluR8 were generated. Next, comparative studies on cell proliferation and migration rates, induction of apoptosis and chemosensitivity were performed among these clones. The mGluR8-downregulated SH-SY5Y clones proliferated faster and were more resistant to cytotoxic action of staurosporine, doxorubicin, irinotecan and cisplatin when compared to control cells. Moreover, these clones were characterized by a lower activity of caspases, calpains and some kinases (GSK-3β, Akt and JNK). The mGluR8-downregulated LN229 clones migrated faster and were less prone to cell-damaging effect of staurosporine and irinotecan when compared with relevant control cells. In contrast, in GRM8-overexpressing U87-MG and LN18 clones, a decreased cell proliferation, increased apoptosis and elevated vulnerability to some cytotoxic agents were found. Altogether, our in vitro data for the first time evidenced a tumor suppressor and chemosensitizing role of mGluR8. Copyright © 2018 Elsevier B.V. All rights reserved.

Adenosine A3 receptor elicits chemoresistance mediated by multiple resistance-associated protein-1 in human glioblastoma stem-like cells.

PubMed

Torres, Angelo; Vargas, Yosselyn; Uribe, Daniel; Jaramillo, Catherine; Gleisner, Alejandra; Salazar-Onfray, Flavio; López, Mercedes N; Melo, Rómulo; Oyarzún, Carlos; San Martín, Rody; Quezada, Claudia

2016-10-11

MRP1 transporter correlates positively with glioma malignancy and the Multiple Drug Resistance (MDR) phenotype in Glioblastoma Multiforme (GBM). Evidence shows that the MRP1 transporter is controlled by the adenosine signalling axis. The aim of this study was to identify the role of adenosine on the MDR phenotype in Glioblastoma Stem-like Cells (GSCs), the cell population responsible for the tumorigenic and chemoresistance capabilities of this tumour. We found that GSCs have increased intrinsic capacity to generate extracellular adenosine, thus controlling MRP1 transporter expression and activity via activation of the adenosine A3 receptor (A3AR). We showed PI3K/Akt and MEK/ERK1/2 signaling pathways downstream A3AR to control MRP1 in GSCs. In vitro pharmacological blockade of A3AR had a chemosensitizing effect, enhancing the actions of antitumour drugs and decreasing cell viability and proliferation of GSCs. In addition, we produced an in vivo xenograft model by subcutaneous inoculation of human GSCs in NOD/SCID-IL2Rg null mice. Pharmacological blockade of A3AR generated a chemosensitizing effect, enhancing the effectiveness of the MRP1 transporter substrate, vincristine, reducing tumour size and the levels of CD44 and Nestin stem cell markers as well as the Ki-67 proliferation indicator. In conclusion, we demonstrated the chemosensitizing effect of A3AR blockade on GSCs.

NOXA-Induced Alterations in the Bax/Smac Axis Enhance Sensitivity of Ovarian Cancer Cells to Cisplatin

PubMed Central

Lin, Chao; Zhao, Xin-yu; Li, Lei; Liu, Huan-yi; Cao, Kang; Wan, Yang; Liu, Xin-yu; Nie, Chun-lai; Liu, Lei; Tong, Ai-ping; Deng, Hong-xin; Li, Jiong; Yuan, Zhu; Wei, Yu-quan

2012-01-01

Ovarian cancer is the most common cause of death from gynecologic malignancy. Deregulation of p53 and/or p73-associated apoptotic pathways contribute to the platinum-based resistance in ovarian cancer. NOXA, a pro-apoptotic BH3-only protein, is identified as a transcription target of p53 and/or p73. In this study, we found that genetic variants of Bcl-2 proteins exist among cisplatin-sensitive and -resistant ovarian cancer cells, and the responses of NOXA and Bax to cisplatin are regulated mainly by p53. We further evaluated the effect of NOXA on cisplatin. NOXA induced apoptosis and sensitized A2780s and SKOV3 cells to cisplatin in vitro and in vivo. The effects were mediated by elevated Bax expression, enhanced caspase activation, release of Cyt C and Smac into the cytosol. Furthermore, gene silencing of Bax or Smac significantly attenuated NOXA and/or cisplatin-induced apoptosis in chemosensitive A2780s cells, whereas overexpression of Bax or addition of Smac-N7 peptide significantly increased NOXA and/or cisplatin-induced apoptosis in chemoresistant SKOV3 cells. To our knowledge, these data suggest a new mechanism by which NOXA chemosensitized ovarian cancer cells to cisplatin by inducing alterations in the Bax/Smac axis. Taken together, our findings show that NOXA is potentially useful as a chemosensitizer in ovarian cancer therapy. PMID:22590594

Chemotherapy-Induced Long Non-coding RNA 1 Promotes Metastasis and Chemo-Resistance of TSCC via the Wnt/β-Catenin Signaling Pathway.

PubMed

Lin, Zhaoyu; Sun, Lijuan; Xie, Shule; Zhang, Shanyi; Fan, Song; Li, Qunxing; Chen, Weixiong; Pan, Guokai; Wang, Weiwei; Weng, Bin; Zhang, Zhang; Liu, Bodu; Li, Jinsong

2018-06-06

Increasing evidence has shown that chemo-resistance is related to the process of epithelial-mesenchymal transition (EMT) and increased invasiveness by tongue squamous cell carcinoma (TSCC) cells. Long non-coding RNAs (lncRNAs) play pivotal roles in tumor metastasis and progression. However, the roles and mechanisms of lncRNAs in cisplatin-resistance-induced EMT and metastasis are not well understood. In this study, a chemotherapy-induced lncRNA 1 (CILA1) was discovered by using microarrays and was functionally identified as a regulator of chemo-sensitivity in TSCC cells. Upregulation of CILA1 promotes EMT, invasiveness, and chemo-resistance in TSCC cells, whereas the inhibition of CILA1 expression induces mesenchymal-epithelial transition (MET) and chemo-sensitivity, and inhibits the invasiveness of cisplatin-resistant cells both in vitro and in vivo. We also found that CILA1 exerts its functions via the activation of the Wnt/β-catenin signaling pathway. High CILA1 expression levels and low levels of phosphorylated β-catenin were closely associated with cisplatin resistance and advanced disease stage, and were predictors of poor prognosis in TSCC patients. These findings provided a new biomarker for the chemo-sensitivity of TSCC tumors and a therapeutic target for TSCC treatment. Copyright © 2018 The American Society of Gene and Cell Therapy. Published by Elsevier Inc. All rights reserved.

Array of Chemosensitive Resistors with Composites of Gas Chromatography (GC) Materials and Carbon Black for Detection and Recognition of VOCs: A Basic Study

PubMed Central

Wyszynski, Bartosz; Yatabe, Rui; Nakao, Atsuo; Nakatani, Masaya; Oki, Akio; Oka, Hiroaki; Toko, Kiyoshi

2017-01-01

Mimicking the biological olfaction, large odor-sensor arrays can be used to acquire a broad range of chemical information, with a potentially high degree of redundancy, to allow for enhanced control over the sensitivity and selectivity of artificial olfaction systems. The arrays should consist of the largest possible number of individual sensing elements while being miniaturized. Chemosensitive resistors are one of the sensing platforms that have a potential to satisfy these two conditions. In this work we test viability of fabricating a 16-element chemosensitive resistor array for detection and recognition of volatile organic compounds (VOCs). The sensors were fabricated using blends of carbon black and gas chromatography (GC) stationary-phase materials preselected based on their sorption properties. Blends of the selected GC materials with carbon black particles were subsequently coated over chemosensitive resistor devices and the resulting sensors/arrays evaluated in exposure experiments against vapors of pyrrole, benzenal, nonanal, and 2-phenethylamine at 150, 300, 450, and 900 ppb. Responses of the fabricated 16-element array were stable and differed for each individual odorant sample, proving the blends of GC materials with carbon black particles can be effectively used for fabrication of large odor-sensing arrays based on chemosensitive resistors. The obtained results suggest that the proposed sensing devices could be effective in discriminating odor/vapor samples at the sub-ppm level. PMID:28696353

Inhibition of p70S6K1 Activation by Pdcd4 Overcomes the Resistance to an IGF-1R/IR Inhibitor in Colon Carcinoma Cells.

PubMed

Zhang, Yan; Wang, Qing; Chen, Li; Yang, Hsin-Sheng

2015-03-01

Agents targeting insulin-like growth factor 1 receptor (IGF-1R) are being actively examined in clinical trials. Although there has been some initial success of single-agent targeting IGF-1R, attempts in later studies failed because of resistance. This study aimed to understand the effects of programmed cell death 4 (Pdcd4) on the chemosensitivity of the IGF-1R inhibitor OSI-906 in colorectal cancer cells and the mechanism underlying this impact. Using OSI-906-resistant and -sensitive colorectal cancer cells, we found that the Pdcd4 level directly correlates with cell chemosensitivity to OSI-906. In addition, tumors derived from Pdcd4 knockdown cells resist the growth inhibitory effect of OSI-906 in a colorectal cancer xenograft mouse model. Moreover, Pdcd4 enhances the antiproliferative effect of OSI-906 in resistant cells through suppression of p70S6K1 activation. Knockdown of p70S6K1, but not p70S6K2, significantly increases the chemosensitivity of OSI-906 in cultured colorectal cancer cells. Furthermore, the combination of OSI-906 and PF-4708671, a p70S6K1 inhibitor, efficiently suppresses the growth of OSI-906-resistant colon tumor cells in vitro and in vivo. Taken together, activation of p70S6K1 that is inhibited by Pdcd4 is essential for resistance to the IGF-1R inhibitor in colon tumor cells, and the combinational treatment of OSI-906 and PF-4708671 results in enhanced antiproliferation effects in colorectal cancer cells in vitro and in vivo, providing a novel venue to overcome the resistance to the IGF-1R inhibitor in treating colorectal cancer. ©2015 American Association for Cancer Research.

NUAK1 (ARK5) Is Associated with Poor Prognosis in Ovarian Cancer.

PubMed

Phippen, Neil T; Bateman, Nicholas W; Wang, Guisong; Conrads, Kelly A; Ao, Wei; Teng, Pang-Ning; Litzi, Tracy A; Oliver, Julie; Maxwell, G Larry; Hamilton, Chad A; Darcy, Kathleen M; Conrads, Thomas P

2016-01-01

Nua kinase 1 (NUAK1) was identified in multigene signatures of survival and suboptimal debulking in high-grade serous ovarian cancer (HGSOC). This study investigates the individual clinical and biologic contributions of NUAK1 in HGSOC patients and cell lines. Public transcript expression, clinical, and outcome data were used to interrogate the relationship between NUAK1 and clinicopathologic factors and patient outcomes including progression-free survival (PFS) and molecular subtypes using logistic and Cox modeling. Analysis of NUAK1 transcript expression was performed in primary tumors from 34 HGSOC patients with < or ≥2 years PFS. The impact of silencing NUAK1 by RNA interference (RNAi) on the migratory potential and chemosensitivity of SOC cells was assessed in vitro . Elevated NUAK1 transcript expression was associated with worse PFS (hazard ratio = 1.134), advanced stage (odds ratio, OR = 1.7), any residual disease (OR = 1.58), and mesenchymal disease subtype (OR = 7.79 ± 5.89). Elevated NUAK1 transcript expression was observed in HGSOC patients with < vs. ≥2 years PFS ( p  < 0.045). RNAi-mediated silencing of NUAK1 expression attenuated migration of OV90 and E3 HGSOC cells in vitro , but did not modulate sensitivity to cisplatin or paclitaxel. Elevated NUAK1 was associated with poor survival as well as advanced stage, residual disease after cytoreductive surgery and mesenchymal molecular subtype. NUAK1 impacted migration, but not chemosensitivity, in vitro . Additional studies are needed to further develop the concept of NUAK1 as a clinically deployable biomarker and therapeutic target in HGSOC.

Assessing Estrogen-Induced Proliferative Response in an Endometrial Cancer Cell Line Using a Universally Applicable Methodological Guide.

PubMed

Parkes, Christina; Kamal, Areege; Valentijn, Anthony J; Alnafakh, Rafah; Gross, Stephane R; Barraclough, Roger; Moss, Diana; Kirwan, John; Hapangama, Dharani K

2018-01-01

Translational endometrial cancer (EC) research benefits from an in vitro experimental approach using EC cell lines. We demonstrated the steps that are required to examine estrogen-induced proliferative response, a simple yet important research question pertinent to EC, and devised a pragmatic methodological workflow for using EC cell lines in experimental models. Comprehensive review of all commercially available EC cell lines was carried out, and Ishikawa cell line was selected to study the estrogen responsiveness with HEC1A, RL95-2, and MFE280 cell lines as comparators where appropriate, examining relevant differential molecular (steroid receptors) and functional (phenotype, anchorage-independent growth, hormone responsiveness, migration, invasion, and chemosensitivity) characteristics in 2-dimensional and 3-dimensional cultures in vitro using immunocytochemistry, immunofluorescence, quantitative polymerase chain reaction, and Western blotting. In vivo tumor, formation, and chemosensitivity were also assessed in a chick chorioallantoic membrane model. Short tandem repeat analysis authenticated the purchased cell lines, whereas gifted cells deviated significantly from the published profile. We demonstrate the importance of prior assessment of the suitability of each cell line for the chosen in vitro experimental technique. Prior establishment of baseline, nonenriched conditions was required to induce a proliferative response to estrogen. The chorioallantoic membrane model was a suitable in vivo multicellular animal model for EC for producing rapid and reproducible data. We have developed a methodological guide for EC researchers when using endometrial cell lines to answer important translational research questions (exemplified by estrogen-responsive cell proliferation) to facilitate robust data, while saving time and resources.

Role of PP2Cα in cell growth, in radio- and chemosensitivity, and in tumorigenicity

PubMed Central

Lammers, Twan; Peschke, Peter; Ehemann, Volker; Debus, Jürgen; Slobodin, Boris; Lavi, Sara; Huber, Peter

2007-01-01

Background PP2Cα is the representative member of the type 2C family of protein phosphatases, and it has recently been implicated in the regulation of p53-, TGFβ-, cyclin-dependent kinase- and apoptosis-signaling. To investigate the role of PP2Cα in cell growth and in radio- and chemosensitivity, wild type and PP2Cα siRNA-expressing MCF7 cells were subjected to several different viability and cell cycle analyses, both under basal conditions and upon treatment with radio- and chemotherapy. By comparing the growth of tumors established from both types of cells, we also evaluated the involvement of PP2Cα in tumorigenesis. Results It was found that knockdown of PP2Cα did not affect the proliferation, the clonogenic survival and the membrane integrity of MCF7 cells. In addition, it did not alter their radio- and chemosensitivity. For PP2Cα siRNA-expressing MCF7 cells, the number of cells in the G0/G1 phase of the cell cycle was reduced, the induction of the G1 block was attenuated, the number of cells in G2/M was increased, and the induction of the G2 block was enhanced. The tumorigenic potential of PP2Cα siRNA-expressing MCF7 cells was found to be higher than that of wild type MCF7 cells, and the in vivo proliferation of these cells was found to be increased. Conclusion Based on these findings, we conclude that PP2Cα is not involved in controlling cell growth and radio- and chemosensitivity in vitro. It does, however, play a role in the regulation of the cell cycle, in the induction of cell cycle checkpoints and in tumorigenesis. The latter notion implies that PP2Cα may possess tumor-suppressing properties, and it thereby sets the stage for more elaborate analyses on its involvement in the development and progression of cancer. PMID:17941990

A prototype methodology combining surface-enhanced laser desorption/ionization protein chip technology and artificial neural network algorithms to predict the chemoresponsiveness of breast cancer cell lines exposed to Paclitaxel and Doxorubicin under in vitro conditions.

PubMed

Mian, Shahid; Ball, Graham; Hornbuckle, Jo; Holding, Finn; Carmichael, James; Ellis, Ian; Ali, Selman; Li, Geng; McArdle, Stephanie; Creaser, Colin; Rees, Robert

2003-09-01

An ability to predict the likelihood of cellular response towards particular chemotherapeutic agents based upon protein expression patterns could facilitate the identification of biological molecules with previously undefined roles in the process of chemoresistance/chemosensitivity, and if robust enough these patterns might also be exploited towards the development of novel predictive assays. To ascertain whether proteomic based molecular profiling in conjunction with artificial neural network (ANN) algorithms could be applied towards the specific recognition of phenotypic patterns between either control or drug treated and chemosensitive or chemoresistant cellular populations, a combined approach involving MALDI-TOF matrix-assisted laser desorption/ionization-time of flight mass spectrometry, Ciphergen protein chip technology and ANN algorithms have been applied to specifically identify proteomic 'fingerprints' indicative of treatment regimen for chemosensitive (MCF-7, T47D) and chemoresistant (MCF-7/ADR) breast cancer cell lines following exposure to Doxorubicin or Paclitaxel. The results indicate that proteomic patterns can be identified by ANN algorithms to correctly assign 'class' for treatment regimen (e.g. control/drug treated or chemosensitive/chemoresistant) with a high degree of accuracy using boot-strap statistical validation techniques and that biomarker ion patterns indicative of response/non-response phenotypes are associated with MCF-7 and MCF-7/ADR cells exposed to Doxorubicin. We have also examined the predictive capability of this approach towards MCF-7 and T47D cells to ascertain whether prediction could be made based upon treatment regimen irrespective of cell lineage. Models were identified that could correctly assign class (control or Paclitaxel treatment) for 35/38 samples of an independent dataset. A similar level of predictive capability was also found (> 92%; n = 28) when proteomic patterns derived from the drug resistant cell line MCF-7/ADR were compared against those derived from MCF-7 and T47D as a model system of drug resistant and drug sensitive phenotypes. This approach might offer a potential methodology for predicting the biological behaviour of cancer cells towards particular chemotherapeutics and through protein isolation and sequence identification could result in the identification of biological molecules associated with chemosensitive/chemoresistance tumour phenotypes.

Adenosine A3 receptor elicits chemoresistance mediated by multiple resistance-associated protein-1 in human glioblastoma stem-like cells

PubMed Central

Torres, Angelo; Vargas, Yosselyn; Uribe, Daniel; Jaramillo, Catherine; Gleisner, Alejandra; Salazar-Onfray, Flavio; López, Mercedes N.; Melo, Rómulo; Oyarzún, Carlos; Martín, Rody San; Quezada, Claudia

2016-01-01

MRP1 transporter correlates positively with glioma malignancy and the Multiple Drug Resistance (MDR) phenotype in Glioblastoma Multiforme (GBM). Evidence shows that the MRP1 transporter is controlled by the adenosine signalling axis. The aim of this study was to identify the role of adenosine on the MDR phenotype in Glioblastoma Stem-like Cells (GSCs), the cell population responsible for the tumorigenic and chemoresistance capabilities of this tumour. We found that GSCs have increased intrinsic capacity to generate extracellular adenosine, thus controlling MRP1 transporter expression and activity via activation of the adenosine A3 receptor (A3AR). We showed PI3K/Akt and MEK/ERK1/2 signaling pathways downstream A3AR to control MRP1 in GSCs. In vitro pharmacological blockade of A3AR had a chemosensitizing effect, enhancing the actions of antitumour drugs and decreasing cell viability and proliferation of GSCs. In addition, we produced an in vivo xenograft model by subcutaneous inoculation of human GSCs in NOD/SCID-IL2Rg null mice. Pharmacological blockade of A3AR generated a chemosensitizing effect, enhancing the effectiveness of the MRP1 transporter substrate, vincristine, reducing tumour size and the levels of CD44 and Nestin stem cell markers as well as the Ki-67 proliferation indicator. In conclusion, we demonstrated the chemosensitizing effect of A3AR blockade on GSCs. PMID:27634913

The potential use of primary human upper urinary tract urothelial cell carcinoma (UUT-UCC) cultured cells for prognostic indicators and chemosensitivity test.

PubMed

Hsieh, Teng-Fu; Chen, Chi-Cheng; Chang, Chao-Hsiang; Yu, Ai-Lin; Ma, Wen-Lung; Shyr, Chih-Rong

2013-07-01

Upper urinary tract urothelial cell carcinoma (UUT-UCC) is a rare yet aggressive urologic tumor with a high rate of recurrence and metastasis, resulting in high mortality. Chemotherapy has been used to prevent recurrence and treat metastatic UUT-UCCs. Although UUT-UCC is sensitive to chemotherapy, the patients' responses to therapy vary and the therapy outcome is unpredictable. Therefore, the identification of patients who are at high risk of failure in chemotherapy is important for accurate prognostication, patient counseling, and better therapy. We have obtained cells from UUT-UCC tumor tissues after surgery and established individual primary cultured cell lines, which were used to evaluate E-cadherin and Ki-67 proliferation marker expression and their chemosensitivity to chemotherapeutic drugs. Differential Ki-67 expression and chemosensitivity were observed in these primary cultured cell lines, suggesting these types of UUT-UCC cell lines could provide a platform for determining prognostic makers and evaluating the efficacy of chemotherapy. In conclusion, primary cultured cell lines from individual patients will be a great tool for evaluating and determining each individual's personalized chemotherapy course and for testing and screening new chemotherapeutic agents against UUT-UCCs. Copyright © 2012 Elsevier GmbH. All rights reserved.

Nitrogen-containing ecdysteroid derivatives vs. multi-drug resistance in cancer: Preparation and antitumor activity of oximes, oxime ethers and a lactam.

PubMed

Vágvölgyi, Máté; Martins, Ana; Kulmány, Ágnes; Zupkó, István; Gáti, Tamás; Simon, András; Tóth, Gábor; Hunyadi, Attila

2018-01-20

Multidrug resistance is a widespread problem among various diseases and cancer is no exception. We had previously described the chemo-sensitizing activity of ecdysteroid derivatives with low polarity on drug susceptible and multi-drug resistant (MDR) cancer cells. We have also shown that these molecules have a marked selectivity towards the MDR cells. Recent studies on the oximation of various steroid derivatives indicated remarkable increase in their antitumor activity, but there is no related bioactivity data on ecdysteroid oximes. In our present study, 13 novel ecdysteroid derivatives (oximes, oxime ethers and a lactam) and one known compound were synthesized from 20-hydroxyecdysone 2,3;20,22-diacetonide and fully characterized by comprehensive NMR techniques revealing their complete 1 H and 13 C signal assignments. The compounds exerted moderate to strong in vitro antiproliferative activity on HeLa, SiHa, MCF-7 and MDA-MB-231 cell lines. Oxime and particularly oxime ether formation strongly increased their inhibitory activity on the efflux of rhodamine 123 by P-glycoprotein (P-gp), while the new ecdysteroid lactam did not interfere with the efflux function. All compounds exerted potent chemo-sensitizing activity towards doxorubicin on a mouse lymphoma cell line and on its MDR counterpart, and, on the latter, the lactam was found the most active. Because of its MDR-selective chemo-sensitizing activity with no functional effect on P-gp, this lactam is of high potential interest as a new lead for further antitumor studies. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Cancer-adipose tissue interaction and fluid flow synergistically modulate cell kinetics, HER2 expression, and trastuzumab efficacy in gastric cancer.

PubMed

Akutagawa, Takashi; Aoki, Shigehisa; Yamamoto-Rikitake, Mihoko; Iwakiri, Ryuichi; Fujimoto, Kazuma; Toda, Shuji

2018-04-25

Early local tumor invasion in gastric cancer results in likely encounters between cancer cells and submucosal and subserosal adipose tissue, but these interactions remain to be clarified. Microenvironmental mechanical forces, such as fluid flow, are known to modulate normal cell kinetics, but the effects of fluid flow on gastric cancer cells are poorly understood. We analyzed the cell kinetics and chemosensitivity in gastric cancer using a simple in vitro model that simultaneously replicated the cancer-adipocyte interaction and physical microenvironment. Gastric cancer cells (MKN7 and MKN74) were seeded on rat adipose tissue fragment-embedded discs or collagen discs alone. To generate fluid flow, samples were placed on a rotatory shaker in a CO 2 incubator. Proliferation, apoptosis, invasion, and motility-related molecules were analyzed by morphometry and immunostaining. Proteins were evaluated by western blot analysis. Chemosensitivity was investigated by trastuzumab treatment. Adipose tissue and fluid flow had a positive synergistic effect on the proliferative potential and invasive capacity of gastric cancer cells, and adipose tissue inhibited apoptosis in these cells. Adipose tissue upregulated ERK1/2 signaling in gastric cancer cells, but downregulated p38 signaling. Notably, adipose tissue and fluid flow promoted membranous and cytoplasmic HER2 expression and modulated chemosensitivity to trastuzumab in gastric cancer cells. We have demonstrated that cancer-adipocyte interaction and physical microenvironment mutually modulate gastric cancer cell kinetics. Further elucidation of the microenvironmental regulation in gastric cancer will be very important for the development of strategies involving molecular targeted therapy.

A new O6-alkylguanine-DNA alkyltransferase inhibitor associated with a nitrosourea (cystemustine) validates a strategy of melanoma-targeted therapy in murine B16 and human-resistant M4Beu melanoma xenograft models.

PubMed

Rapp, Maryse; Maurizis, Jean C; Papon, Janine; Labarre, Pierre; Wu, Ting-Di; Croisy, Alain; Guerquin-Kern, Jean L; Madelmont, Jean C; Mounetou, Emmanuelle

2008-07-01

Chemoresistance to O(6)-alkylating agents is a major barrier to successful treatment of melanoma. It is mainly due to a DNA repair suicide protein, O(6)-alkylguanine-DNA alkyltransferase (AGT). Although AGT inactivation is a powerful clinical strategy for restoring tumor chemosensitivity, it was limited by increased toxicity to nontumoral cells resulting from a lack of tumor selectivity. Achieving enhanced chemosensitization via AGT inhibition preferably in the tumor should protect normal tissue. To this end, we have developed a strategy to target AGT inhibitors. In this study, we tested a new potential melanoma-directed AGT inhibitor [2-amino-6-(4-iodobenzyloxy)-9-[4-(diethylamino) ethylcarbamoylbenzyl] purine; IBgBZ] designed as a conjugate of O(6)-(4-iododbenzyl)guanine (IBg) as the AGT inactivator and a N,N-diethylaminoethylenebenzamido (BZ) moiety as the carrier to the malignant melanocytes. IBgBZ demonstrated AGT inactivation ability and potentiation of O(6)-alkylating agents (cystemustine, a chloroethylnitrosourea) in M4Beu highly chemoresistant human melanoma cells both in vitro and in tumor models. The biodisposition study on mice bearing B16 melanoma, the standard model for the evaluation of melanoma-directed agents, and the secondary ion mass spectrometry imaging confirmed the concentration of IBgBZ in the tumor and in particular in the intracytoplasmic melanosomes. These results validate the potential of IBgBZ as a new, more tumor-selective, AGT inhibitor in a strategy of melanoma-targeted therapy.

Correlation of Early Recurrence With In Vitro Adenosine Triphosphate Based Chemotherapy Response Assay in Pancreas Cancer With Postoperative Gemcitabine Chemotherapy.

PubMed

Park, Joon Seong; Kim, Jae Keun; Yoon, Dong Sup

2016-11-01

Gemcitabine-based regimens represent the standard systemic first line treatment in patients after pancreatic resection. However, the clinical impact of gemcitabine varies significantly in individuals because of chemoresistance. An in vitro adenosine triphosphate based chemotherapy response assay (ATP-CRA) was designed to evaluate the sensitivity of cancer cells to various chemotherapeutic agents. This study investigated the correlation between in vitro gemcitabine sensitivity of tumor cells and early recurrence after curative resection. From January 2007 to December 2010, the ATP-CRA for gemcitabine was tested in 64 patients surgically treated for pancreas cancer at Gangnam Severance Hospital, Seoul, Korea. We analyzed the relationship between chemosensitivity and early systemic recurrence in patients with pancreas cancer to predict disease-free survival (DFS) after curative resection in pancreas cancer. The mean cell death rate (CDR) was 20.0 (±14.5) and divided into two groups according to the mean values of the CDR. Lymphovascular invasion was more frequently shown in gemcitabine resistance group without statistical significance. In univariate and multivariate analysis, advanced tumor stage and gemcitabine sensitive group (CDR ≥ 20) were identified as independent prognostic factors for DFS. Gemcitabine sensitivity measured by ATP-CRA was well correlated with in vivo drug responsibility to predict early recurrence following gemcitabine-based adjuvant chemotherapy in patients with pancreas cancer. © 2016 Wiley Periodicals, Inc.

Screening and evaluation of anticancer agents.

PubMed

Zee-Cheng, R K; Cheng, C C

1988-02-01

The screening and evaluation procedures for the development of anticancer agents indicated that the entire process is a rather difficult task. This is particularly true in choosing screening models and criteria for activity. If the criteria were set too low, then some clinically false-positive results may be faced; and if the criteria were set too high, some agents could be missed which might be effective against certain types of human cancer. Presently, active compounds are selected by prescreening and screening against transplanted mouse tumors and human tumor xenografts as well as by the in vitro systems. Xenografts of human tumor in athymic nude animals represent metabolic characteristics of human malignant disease which appear to be of value in the preclinical screening. Human tumor cloning assays have gained increased attention as a promising in vitro test system for the screening as well as for the prediction of patient responses. Application of chemosensitivity tests in the prediction of the responses of individuals to chemotherapy, especially in the identification of drug resistant tumors are, in general, quite reliable. Human tumor xenografts, human tumor cloning assays and chemosensitivity tests may be regarded as the major impetus in screening during the past decade. After promising agents are selected from the screening procedures, before the filing of an investigational new drug application, the preclinical toxicology and pharmacology should be completed. Information on the nature of toxicity, dose-response effects, and dose schedule are necessary for predicting the effects of the drug in man. The new drugs then go through three phases of clinical trials to assure safety, effectiveness, and reliability of the drugs. During the past fifteen years eight-three antineoplastic drugs were evaluated clinically under the NCI sponsorship and twenty-four are active in at least one disease. Among these active drugs, eleven possess novel clinical structure, the remaining thirteen are analogues of known active compounds already in clinical trials. After an investigational anticancer drug is approved by the U.S. Food and Drug Administration it becomes a commercial product on the market and the benefits can be shared by the general public. The time required for evaluation and development from the first discovery of activity to final FDA approval for fifty-two therapeutic drugs are tabled. The average interval is 8.8 years, but in the 1950s the average was only 2.8 years, in the 1960s, 6.5 years; in the 1970s, 13.9 years; and in the 1980s, 16.0 years. This reflects the increasing stricter requirements for an antineoplastic drug to be officially recognize

[Lentivirus-mediated RNA interference of CD133 inhibits the proliferation of CD133(+) liver cancer stem cells and increases their cisplatin chemosensitivity].

PubMed

Lan, Xi; Wang, Yong; Cao, Shu; Zou, Dongling; Li, Fang; Li, Shaolin

2012-12-01

To study the effects of CD133 suppression by lentivirus-mediated RNA interference (RNAi) on the proliferation and chemosensitivity of CD133(+) cancer stem cells (CSCs) sorted from HepG2 cell line. CD133(+) and CD133- cells were sorted from HepG2 cell line by flow cytometry, and the expression of CD133 before and after cell sorting were detected. The stem cell property of sorted CD133(+) cells were validated by sphere-forming assay in vitro and xenograft experiments in vivo. Lentivirus-mediated short hairpin RNA (shRNA) targeting CD133 were transfected into CD133(+) cells, and CD133 mRNA and protein expressions of the transfected cells were detected by RT-PCR and Western blotting, respectively. Before and after the transfection, the proliferative ability of CD133(+) cells was evaluated by colony formation assay, and the cell growth inhibition rate and apoptosis following cisplatin exposure were detected using CCK-8 assay and flow cytometry. The sorted CD133(+) cells showed a high purity of (88.74∓3.19)%, as compared with the purity of (3.36∓1.80)% before cell sorting. CD133(+) cells showed a high tumor sphere formation ability and tumorigenesis capacity compared with CD133- cells. CD133 shRNA transfection significantly inhibited CD133 mRNA and protein expressions in CD133(+) cells (P<0.01), resulting also in a significantly lowered cell proliferative ability (P<0.01) and an increased growth inhibition rate (P<0.01) and obviously increased cell apoptosis (P<0.05) after cisplatin exposure. Lentivirus-mediated RNAi for CD133 suppression inhibits the proliferation of CD133(+) liver cancer stem cells and increases their chemosensitivity to cisplatin.

Impedimetric quantification of the formation process and the chemosensitivity of cancer cell colonies suspended in 3D environment.

PubMed

Lei, Kin Fong; Wu, Zong-Ming; Huang, Chia-Hao

2015-12-15

In cancer research, colony formation assay is a gold standard for the investigation of the development of early tumors and the effects of cytotoxic agents on tumors in vitro. Quantification of cancer cell colonies suspended in hydrogel is currently achieved by manual counting under microscope. It is challenging to microscopically quantify the colony number and size without subjective bias. In this work, impedimetric quantification of cancer cell colonies suspended in hydrogel was successfully developed and provides a quantitative and objective method to describe the colony formation process and the development of colony size during the culture course. A biosensor embedded with a pair of parallel plate electrodes was fabricated for the impedimetric quantification. Cancer cell (cell line: Huh-7) were encapsulated in methyl cellulose hydrogel and cultured to gradually form cancer cell colonies suspended in 3D environment. At pre-set schedule during the culture course, small volume (50 μL) of colonies/MC hydrogel was collected, mixed with measurement hydrogel, and loaded to the biosensor for measurement. Hence, the colony formation process could be quantitatively represented by a colony index and a colony size index calculated from electrical impedance. Based on these developments, chemosensitivity of cancer cell colonies under different concentrations of anti-cancer drug, i.e., doxorubicin, was quantitatively investigated to study the efficacy of anti-cancer drug. Also, dose-response curve was constructed to calculate the IC50 value, which is an important indicator for chemosensitivity assay. These results showed the impedimetric quantification is a promising technique for the colony formation assay. Copyright © 2015 Elsevier B.V. All rights reserved.

3, 3′- DIINDOLYLMETHANE ENHANCES CHEMOSENSITIVITY OF MULTIPLE CHEMOTHERAPEUTIC AGENTS IN PANCREATIC CANCER

PubMed Central

Banerjee, Sanjeev; Wang, Zhiwei; Kong, Dejuan; Sarkar, Fazlul H.

2009-01-01

Clinical management of pancreatic cancer (PC) is a major problem, which is in part due to both de novo and acquired resistance to conventional therapeutics. Here, we present in vitro and in vivo preclinical evidence in support of chemo-sensitization of PC cells by DIM, a natural compound that can be easily obtained by consuming cruciferous vegetables. DIM pretreatment of PC cells led to a significantly increased apoptosis (p<0.01) with suboptimal concentrations of chemotherapeutic agents (cisplatin, gemcitabine and oxaliplatin) compared to monotherapy. It is known that resistance to chemotherapy in PC is associated with constitutively activated NF-κB, which becomes further activated by chemotherapeutic drugs. Our data provide mechanistic evidence for the first time showing that DIM potentiates the killing of PC cells by down-regulation of constitutive as well as drug induced activation of NF-κB and its downstream genes (Bcl-xL, XIAP, c-IAP, survivin). Most importantly, using an orthotopic animal model, we found reduction in tumor size (p<0.001) when DIM was given in combination with oxaliplatin compared to monotherapy. This was accompanied by loss of phospho p-65, down-regulation of NF-κB activity and its downstream genes (Bcl-xL, survivin and XIAP), which correlated with reduced cell proliferation (as assessed by Ki-67 immunostaining of tumor specimens) and evidence of apoptosis (as assessed by PARP cleavage and TUNEL staining). These results provide strong in vivo evidence in support of our hypothesis that DIM could abrogate chemotherapeutic drug (cisplatin, gemcitabine and/or oxaliplatin) induced activation of NF-κB, resulting in the chemo-sensitization of pancreatic tumors to conventional therapeutics. PMID:19531648

Chemosensitivity of BRCA1-Mutated Ovarian Cancer Cells and Established Cytotoxic Agents.

PubMed

van Haaften, Caroline; van Eendenburg, Jaap; Boot, Arnoud; Corver, Willem E; Haans, Lucien; van Wezel, Tom; Trimbos, J Baptist

2017-10-01

Serous adenocarcinomas that arise in patients with inherited mutations in the tumor suppressor genes BRCA1 and BRCA2 are initially well treatable with platinum/paclitaxel. For recurrent disease in patients with BRCA1 or BRCA2 mutations, olaparib treatment is available. To study additional therapeutic regimens, a better understanding of the cellular and molecular mechanisms of the tumors in in vitro models is important. From a high-grade serous ovarian tumor of a BRCA1 mutation carrier, we established 3 distinct cell line subclones, OVCA-TR3.1, -2, and -3. Immunohistochemical characterization, flow cytometric analyses, chemosensitivity, and somatic mutation profiling were performed. The cell lines expressed AE1/AE3, Pax8, WT-1, OC125, estrogen receptor (ER), and p53, comparable to the primary tumor. Synergism could be shown in the combination treatment eremophila-1-(10)-11(13)-dien-12,8β-olide (EPD), with cisplatin, whereas combination with olaparib did not show synergism. Eremophila-1-(10)-11(13)-dien-12,8β-olide, a sesquiterpene lactone, is a novel chemotherapeutic agent. The inherited BRCA1 c.2989_2990dupAA mutation was confirmed in the cell lines. Loss of heterozygosity of BRCA1 was detected in each cell line, as well as a homozygous TP53 c.722C>A mutation. Flow cytometry showed that all cell lines had a distinct DNA index. Three new isogenic ovarian cancer cell lines were developed from a patient with a germ line BRCA1 mutation. Chemosensitivity profiling of the cell lines showed high tolerance for olaparib. Treatment with EPD proved synergistic with cisplatin. The effects of EPD will be further investigated for future clinical efficacy.

IGF-1R inhibition induces schedule-dependent sensitization of human melanoma to temozolomide

PubMed Central

Ramcharan, Roger; Aleksic, Tamara; Kamdoum, Wilfride Petnga; Gao, Shan; Pfister, Sophia X.; Tanner, Jordan; Bridges, Esther; Asher, Ruth; Watson, Amanda J.; Margison, Geoffrey P.; Woodcock, Mick; Repapi, Emmanouela; Li, Ji-Liang; Middleton, Mark R.; Macaulay, Valentine M.

2015-01-01

Prior studies implicate type 1 IGF receptor (IGF-1R) in mediating chemo-resistance. Here, we investigated whether IGF-1R influences response to temozolomide (TMZ), which generates DNA adducts that are removed by O6-methylguanine-DNA methyltransferase (MGMT), or persist causing replication-associated double-strand breaks (DSBs). Initial assessment in 10 melanoma cell lines revealed that TMZ resistance correlated with MGMT expression (r = 0.79, p = 0.009), and in MGMT-proficient cell lines, with phospho-IGF-1R (r = 0.81, p = 0.038), suggesting that TMZ resistance associates with IGF-1R activation. Next, effects of IGF-1R inhibitors (IGF-1Ri) AZ3801 and linsitinib (OSI-906) were tested on TMZ-sensitivity, cell cycle progression and DSB induction. IGF-1Ri sensitized BRAF wild-type and mutant melanoma cells to TMZ in vitro, an effect that was independent of MGMT. Cells harboring wild-type p53 were more sensitive to IGF-1Ri, and showed schedule-dependent chemo-sensitization that was most effective when IGF-1Ri followed TMZ. This sequence sensitized to clinically-achievable TMZ concentrations and enhanced TMZ-induced apoptosis. Simultaneous or prior IGF-1Ri caused less effective chemo-sensitization, associated with increased G1 population and reduced accumulation of TMZ-induced DSBs. Clinically relevant sequential (TMZ → IGF-1Ri) treatment was tested in mice bearing A375M (V600E BRAF, wild-type p53) melanoma xenografts, achieving peak plasma/tumor IGF-1Ri levels comparable to clinical Cmax, and inducing extensive intratumoral apoptosis. TMZ or IGF-1Ri caused minor inhibition of tumor growth (gradient reduction 13%, 25% respectively), while combination treatment caused supra-additive growth delay (72%) that was significantly different from control (p < 0.01), TMZ (p < 0.01) and IGF-1Ri (p < 0.05) groups. These data highlight the importance of scheduling when combining IGF-1Ri and other targeted agents with drugs that induce replication-associated DNA damage. PMID:26497996

Restoration of chemosensitivity in cancer cells with MDR phenotype by deoxyribozyme, compared with ribozyme.

PubMed

Xing, Ai-Yan; Shi, Duan-bo; Liu, Wei; Chen, Xu; Sun, Yan-Lin; Wang, Xiao; Zhang, Jian-ping; Gao, Peng

2013-06-01

One of the main mechanisms for multidrug resistance (MDR) involves multidrug resistance gene 1 (MDR1) which encodes P-glycoprotein (Pgp). Pgp acts as a drug efflux pump and exports chemotherapeutic agents from cancer cells. Specific inhibition of Pgp expression by gene therapy is considered a well-respective strategy having less innate toxicities. At present, the investigation of DRz in reversal MDR is scarce. In the study, phosphorothioate DRz that targets to the translation initiation codon AUG was synthesized and transfected into breast cancer cells and leukemia cells with MDR phenotype. ASODN (antisense oligonucleotide) and ribozyme targets to the same region were also synthesized for comparison analysis. Alterations in MDR1 mRNA and Pgp were determined by RT-PCR, Northern blot, flow cytometry and Rh123 retention tests. Chemosensitivity of the treated cells was determined by MTT assay. The results showed that DRz could significantly suppress expression of MDR1 mRNA and inhibit synthesis of Pgp. The efflux activity of Pgp was inhibited accordingly. Chemosensitivity assay showed that a 21-fold reduction in drug resistance for Adriamycin and a 45-fold reduction in drug resistance for Vinblastine were found in the treated cells 36h after transfection. These data suggest that DRz targeted to the translation initiation codon AUG can reverse MDR phenotype in cancer cells and restore their chemosensitivity. Moreover, the reversal efficiency of DRz is better than that of ribozyme and ASODN targets to the same region of MDR1 mRNA. Copyright © 2013 Elsevier Inc. All rights reserved.

Regulation of ventral surface chemoreceptors by the central respiratory pattern generator.

PubMed

Guyenet, Patrice G; Mulkey, Daniel K; Stornetta, Ruth L; Bayliss, Douglas A

2005-09-28

The rat retrotrapezoid nucleus (RTN) contains neurons described as central chemoreceptors in the adult and respiratory rhythm-generating pacemakers in neonates [parafacial respiratory group (pfRG)]. Here we test the hypothesis that both RTN and pfRG neurons are intrinsically chemosensitive and tonically firing neurons whose respiratory rhythmicity is caused by a synaptic feedback from the central respiratory pattern generator (CPG). In halothane-anesthetized adults, RTN neurons were silent below 4.5% end-expiratory (e-exp) CO2. Their activity increased linearly (3.2 Hz/1% CO2) up to 6.5% (CPG threshold) and then more slowly to peak approximately 10 Hz at 10% CO2. Respiratory modulation of RTN neurons was absent below CPG threshold, gradually stronger beyond, and, like pfRG neurons, typically (42%) characterized by twin periods of reduced activity near phrenic inspiration. After CPG inactivation with kynurenate (KYN), RTN neurons discharged linearly as a function of e-exp CO2 (slope, +1.7 Hz/1% CO2) and arterial pH (threshold, 7.48; slope, 39 Hz/pH unit). In coronal brain slices (postnatal days 7-12), RTN chemosensitive neurons were silent at pH 7.55. Their activity increased linearly with acidification up to pH 7.2 (17 Hz/pH unit at 35 degrees C) and was always tonic. In conclusion, consistent with their postulated central chemoreceptor role, RTN/pfRG neurons encode pH linearly and discharge tonically when disconnected from the rest of the respiratory centers in vivo (KYN treatment) and in vitro. In vivo, RTN neurons receive respiratory synchronous inhibitory inputs that may serve as feedback and impart these neurons with their characteristic respiratory modulation.

The microculture tetrazolium assay (MTA): another colorimetric method of testing Plasmodium falciparum chemosensitivity.

PubMed

Delhaes, L; Lazaro, J E; Gay, F; Thellier, M; Danis, M

1999-01-01

Malarial lactate dehydrogenase (LDH), which uses 3-acetyl pyridine adenine dinucleotide as coenzyme in a reaction leading to the formation of pyruvate from L-lactate, may be used to study the susceptibility of Plasmodium falciparum to a drug in vitro. Several methods to determine the activity of this enzyme are available. One, the colorimetric method of Makler and colleagues, was modified slightly, by using sodium-2,3-bis-[2-methoxy-4-nitro-5-sulphophenyl]-2H-tetrazolium-5 - carboxanilide (XTT) and following the reaction by measuring the optical density at 450 nm. Using two, culture-adapted strains of P. falciparum, this LDH assay was compared with the unmodified Makler's assay and with the isotopic microtest based on the incorporation of tritium-labelled hypoxanthine. Fresh, clinical P. falciparum isolates were also tested in the presence of several drugs, including chloroquine, mefloquine, quinine, halofantrine, atovaquone and qinghaosu derivatives. The results of the three assays were correlated for all the drugs tested except atovaquone. The two enzymatic assays are non-radioactive, rapid, reliable, inexpensive to perform and semi-automatic. However, they do require an initial parasitaemia of 2% with a haematocrit of 1.8%.

Left Atrial Size, Chemosensitivity, and Central Sleep Apnea in Heart Failure

PubMed Central

Calvin, Andrew D.; Somers, Virend K.; Johnson, Bruce D.; Scott, Christopher G.

2014-01-01

BACKGROUND: Central sleep apnea (CSA) is common among patients with heart failure (HF) and is promoted by elevated CO2 chemosensitivity. Left atrial size is a marker of the hemodynamic severity of HF. The aim of this study was to determine if left atrial size predicts chemosensitivity to CO2 and CSA in patients with HF. METHODS: Patients with HF with left ventricular ejection fraction ≤ 35% underwent polysomnography for detection of CSA, echocardiography, and measurement of CO2 chemosensitivity. CSA was defined as an apnea-hypopnea index (AHI) ≥ 15/h with ≥ 50% central apneic events. The relation of clinical and echocardiographic parameters to chemosensitivity and CSA were evaluated by linear regression, estimation of ORs, and receiver operator characteristics. RESULTS: Of 46 subjects without OSA who had complete data for analysis, 25 had CSA. The only parameter that significantly correlated with chemosensitivity was left atrial volume index (LAVI) (r = 0.40, P < .01). LAVI was greater in those with CSA than those without CSA (59.2 mL/m2 vs 36.4 mL/m2, P < .001) and significantly correlated with log-transformed AHI (r = 0.46, P = .001). LAVI was the best predictor of CSA (area under the curve = 0.83). A LAVI ≤ 33 mL/m2 was associated with 22% risk for CSA, while LAVI ≥ 53 mL/m2 was associated with 92% risk for CSA. CONCLUSIONS: Increased LAVI is associated with heightened CO2 chemosensitivity and greater frequency of CSA. LAVI may be useful to guide referral for polysomnography for detection of CSA in patients with HF. PMID:24522490

Co-targeting of Tiam1/Rac1 and Notch ameliorates chemoresistance against doxorubicin in a biomimetic 3D lymphoma model

PubMed Central

Ikram, Muhammad; Lim, Yeseon; Baek, Sun-Yong; Jin, Songwan; Jeong, Young Hun; Kwak, Jong-Young; Yoon, Sik

2018-01-01

Lymphoma is a heterogeneous disease with a highly variable clinical course and prognosis. Improving the prognosis for patients with relapsed and treatment-resistant lymphoma remains challenging. Current in vitro drug testing models based on 2D cell culture lack natural tissue-like structural organization and result in disappointing clinical outcomes. The development of efficient drug testing models using 3D cell culture that more accurately reflects in vivo behaviors is vital. Our aim was to establish an in vitro 3D lymphoma model that can imitate the in vivo 3D lymphoma microenvironment. Using this model, we explored strategies to enhance chemosensitivity to doxorubicin, an important chemotherapeutic drug widely used for the treatment of hematological malignancies. Lymphoma cells grown in this model exhibited excellent biomimetic properties compared to conventional 2D culture including (1) enhanced chemotherapy resistance, (2) suppressed rate of apoptosis, (3) upregulated expression of drug resistance genes (MDR1, MRP1, BCRP and HIF-1α), (4) elevated levels of tumor aggressiveness factors including Notch (Notch-1, -2, -3, and -4) and its downstream molecules (Hes-1 and Hey-1), VEGF and MMPs (MMP-2 and MMP-9), and (5) enrichment of a lymphoma stem cell population. Tiam1, a potential biomarker of tumor progression, metastasis, and chemoresistance, was activated in our 3D lymphoma model. Remarkably, we identified two synergistic therapeutic oncotargets, Tiam1 and Notch, as a strategy to combat resistance against doxorubicin in EL4 T and A20 B lymphoma. Therefore, our data suggest that our 3D lymphoma model is a promising in vitro research platform for studying lymphoma biology and therapeutic approaches. PMID:29416753

Reduced expression of DNA repair genes and chemosensitivity in 1p19q codeleted lower-grade gliomas.

PubMed

Tang, Lei; Deng, Lu; Bai, Harrison X; Sun, James; Neale, Natalie; Wu, Jing; Wang, Yinyan; Chang, Ken; Huang, Raymond Y; Zhang, Paul J; Li, Xuejun; Xiao, Bo; Cao, Ya; Tao, Yongguang; Yang, Li

2018-06-19

Lower-grade gliomas (LGGs, defined as WHO grades II and III) with 1p19q codeletion have increased chemosensitivity when compared to LGGs without 1p19q codeletion, but the mechanism is currently unknown. RNAseq data from 515 LGG patients in the Cancer Genome Atlas (TCGA) were analyzed to compare the effect of expression of the 9 DNA repair genes located on chromosome arms 1p and 19q on progression free survival (PFS) and overall survival (OS) between patients who received chemotherapy and those who did not. Chemosensitivity of cells with DNA repair genes knocked down was tested using MTS cell proliferation assay in HS683 cell line and U251 cell line. The expression of 9 DNA repair genes on 1p and 19q was significantly lower in 1p19q-codeleted tumors (n = 175) than in tumors without the codeletion (n = 337) (p < 0.001). In LGG patients who received chemotherapy, lower expression of LIG1, POLD1, PNKP, RAD54L and MUTYH was associated with longer PFS and OS. This difference between chemotherapy and non-chemotherapy groups in the association of gene expression with survival was not observed in non-DNA repair genes located on chromosome arms 1p and 19q. MTS assays showed that knockdown of DNA repair genes LIG1, POLD1, PNKP, RAD54L and MUTYH significantly inhibited recovery in response to temozolomide when compared with control group (p < 0.001). Our results suggest that reduced expression of DNA repair genes on chromosome arms 1p and 19q may account for the increased chemosensitivity of LGGs with 1p19q codeletion.

Temperature influences neuronal activity and CO2/pH sensitivity of locus coeruleus neurons in the bullfrog, Lithobates catesbeianus.

PubMed

Santin, Joseph M; Watters, Kayla C; Putnam, Robert W; Hartzler, Lynn K

2013-12-15

The locus coeruleus (LC) is a chemoreceptive brain stem region in anuran amphibians and contains neurons sensitive to physiological changes in CO2/pH. The ventilatory and central sensitivity to CO2/pH is proportional to the temperature in amphibians, i.e., sensitivity increases with increasing temperature. We hypothesized that LC neurons from bullfrogs, Lithobates catesbeianus, would increase CO2/pH sensitivity with increasing temperature and decrease CO2/pH sensitivity with decreasing temperature. Further, we hypothesized that cooling would decrease, while warming would increase, normocapnic firing rates of LC neurons. To test these hypotheses, we used whole cell patch-clamp electrophysiology to measure firing rate, membrane potential (V(m)), and input resistance (R(in)) in LC neurons in brain stem slices from adult bullfrogs over a physiological range of temperatures during normocapnia and hypercapnia. We found that cooling reduced chemosensitive responses of LC neurons as temperature decreased until elimination of CO2/pH sensitivity at 10°C. Chemosensitive responses increased at elevated temperatures. Surprisingly, chemosensitive LC neurons increased normocapnic firing rate and underwent membrane depolarization when cooled and decreased normocapnic firing rate and underwent membrane hyperpolarization when warmed. These responses to temperature were not observed in nonchemosensitive LC neurons or neurons in a brain stem slice 500 μm rostral to the LC. Our results indicate that modulation of cellular chemosensitivity within the LC during temperature changes may influence temperature-dependent respiratory drive during acid-base disturbances in amphibians. Additionally, cold-activated/warm-inhibited LC neurons introduce paradoxical temperature sensitivity in respiratory control neurons of amphibians.

Prediction of individual response to anticancer therapy: historical and future perspectives.

PubMed

Unger, Florian T; Witte, Irene; David, Kerstin A

2015-02-01

Since the introduction of chemotherapy for cancer treatment in the early 20th century considerable efforts have been made to maximize drug efficiency and at the same time minimize side effects. As there is a great interpatient variability in response to chemotherapy, the development of predictive biomarkers is an ambitious aim for the rapidly growing research area of personalized molecular medicine. The individual prediction of response will improve treatment and thus increase survival and life quality of patients. In the past, cell cultures were used as in vitro models to predict in vivo response to chemotherapy. Several in vitro chemosensitivity assays served as tools to measure miscellaneous endpoints such as DNA damage, apoptosis and cytotoxicity or growth inhibition. Twenty years ago, the development of high-throughput technologies, e.g. cDNA microarrays enabled a more detailed analysis of drug responses. Thousands of genes were screened and expression levels were correlated to drug responses. In addition, mutation analysis became more and more important for the prediction of therapeutic success. Today, as research enters the area of -omics technologies, identification of signaling pathways is a tool to understand molecular mechanism underlying drug resistance. Combining new tissue models, e.g. 3D organoid cultures with modern technologies for biomarker discovery will offer new opportunities to identify new drug targets and in parallel predict individual responses to anticancer therapy. In this review, we present different currently used chemosensitivity assays including 2D and 3D cell culture models and several -omics approaches for the discovery of predictive biomarkers. Furthermore, we discuss the potential of these assays and biomarkers to predict the clinical outcome of individual patients and future perspectives.

The contribution of DNA replication stress marked by high-intensity, pan-nuclear γH2AX staining to chemosensitization by CHK1 and WEE1 inhibitors.

PubMed

Parsels, Leslie A; Parsels, Joshua D; Tanska, Daria M; Maybaum, Jonathan; Lawrence, Theodore S; Morgan, Meredith A

2018-06-12

Small molecule inhibitors of the checkpoint proteins CHK1 and WEE1 are currently in clinical development in combination with the antimetabolite gemcitabine. It is unclear, however, if there is a therapeutic advantage to CHK1 vs. WEE1 inhibition for chemosensitization. The goals of this study were to directly compare the relative efficacies of the CHK1 inhibitor MK8776 and the WEE1 inhibitor AZD1775 to sensitize pancreatic cancer cell lines to gemcitabine and to identify pharmacodynamic biomarkers predictive of chemosensitization. Cells treated with gemcitabine and either MK8776 or AZD1775 were first assessed for clonogenic survival. With the exception of the homologous recombination-defective Capan1 cells, which were relatively insensitive to MK8776, we found that these cell lines were similarly sensitized to gemcitabine by CHK1 or WEE1 inhibition. The abilities of either the CDK1/2 inhibitor roscovitine or exogenous nucleosides to prevent MK8776 or AZD1775-mediated chemosensitization, however, were both inhibitor-dependent and variable among cell lines. Given the importance of DNA replication stress to gemcitabine chemosensitization, we next assessed high-intensity, pan-nuclear γH2AX staining as a pharmacodynamic marker for sensitization. In contrast to total γH2AX, aberrant mitotic entry or sub-G1 DNA content, high-intensity γH2AX staining correlated with chemosensitization by either MK8776 or AZD1775 (R 2 0.83 - 0.53). In summary, we found that MK8776 and AZD1775 sensitize to gemcitabine with similar efficacy. Furthermore, our results suggest that the effects of CHK1 and WEE1 inhibition on gemcitabine-mediated replication stress best predict chemosensitization and support the use of high-intensity or pan-nuclear γH2AX staining as a marker for therapeutic response.

Menadione serves as a substrate for P-glycoprotein: implication in chemosensitizing activity.

PubMed

Oh, Seok-Jeong; Han, Hyo-Kyung; Kang, Keon-Wook; Lee, Young-Joo; Lee, Moo-Yeol

2013-04-01

Based on its chemosensitizing effect, we questioned whether menadione is an inhibitor or a substrate of P-glycoprotein (P-gp). To test this hypothesis, we assessed the effect of menadione on P-gp activity and examined the P-gp-dependency of cellular accumulation and cytotoxicity of menadione as well. Treatment with menadione resulted in the concentration-dependent increase of rhodamine 123 (Rh123) accumulation in P-gp-overexpressing MDCKII/MDR1 and NCI/ADR-RES cells, suggesting that menadione inhibits Rh123 extrusion by P-gp. Compared with MDCKII or MCF-7, intracellular distribution of [(3)H]-menadione was significantly lower in MDCKII/MDR1 or NCI/ADR-RES cells, which could be restored by the P-gp inhibitors, verapamil and quinidine. Consistent with these results, MDCKII/MDR1 or NCI/ADR-RES cells were more resistant to the cytotoxicity of menadione than MDCKII or MCF-7 cells, respectively. Such resistance was abolished by the combined treatment of verapamil and quinidine in NCI/ADR-RES cells. Our study identified menadione as a substrate of P-gp, which presumably, acts as the mechanism for the chemosensitizing effect. Menadione may be a promising chemotherapeutic enhancer by its ability of circumventing drug resistance, in addition to its own anti-cancer activity.

A new agent developed by biotransformation of polyphyllin VII inhibits chemoresistance in breast cancer.

PubMed

He, Dong-Xu; Li, Guo-Hong; Gu, Xiao-Ting; Zhang, Liang; Mao, Ai-Qin; Wei, Juan; Liu, De-Quan; Shi, Gui-Yang; Ma, Xin

2016-05-31

Biotransformation by the endophytes of certain plants changes various compounds, and this 'green' chemistry becomes increasingly important for finding new products with pharmacological activity. In this study, polyphyllin VII (PPL7) was biotransformed by endophytes from the medicinal plant Paris polyphylla Smith, var. yunnanensis. This produced a new compound, ZH-2, with pharmacological activity in vitro and in vivo. ZH-2 was more potent than PPL7 in selectively killing more chemoresistant than chemosensitive breast cancer cells. ZH-2 also re-sensitized chemoresistant breast cancer cells, as evidenced by the improved anti-cancer activity of commonly-used chemotherapeutic agent in vitro, in vivo, and in clinical samples. This anti-chemoresistance effect of ZH-2 was associated with inhibiting the epithelial-mesenchymal transition (EMT) pathway. Taken together, our findings are the first one to link biotransformation with a biomedicine. The results provide insights into developing new pharmacologically-active agents via biotransformation by endophytes.

Chemosensitization of Fusarium graminearum to Chemical Fungicides Using Cyclic Lipopeptides Produced by Bacillus amyloliquefaciens Strain JCK-12

PubMed Central

Kim, Kihyun; Lee, Yoonji; Ha, Areum; Kim, Ji-In; Park, Ae Ran; Yu, Nan Hee; Son, Hokyoung; Choi, Gyung Ja; Park, Hae Woong; Lee, Chul Won; Lee, Theresa; Lee, Yin-Won; Kim, Jin-Cheol

2017-01-01

Fusarium head blight (FHB) caused by infection with Fusarium graminearum leads to enormous losses to crop growers, and may contaminate grains with a number of Fusarium mycotoxins that pose serious risks to human and animal health. Antagonistic bacteria that are used to prevent FHB offer attractive alternatives or supplements to synthetic fungicides for controlling FHB without the negative effects of chemical management. Out of 500 bacterial strains isolated from soil, Bacillus amyloliquefaciens JCK-12 showed strong antifungal activity and was considered a potential source for control strategies to reduce FHB. B. amyloliquefaciens JCK-12 produces several cyclic lipopeptides (CLPs) including iturin A, fengycin, and surfactin. Iturin A inhibits spore germination of F. graminearum. Fengycin or surfactin alone did not display any inhibitory activity against spore germination at concentrations less than 30 μg/ml, but a mixture of iturin A, fengycin, and surfactin showed a remarkable synergistic inhibitory effect on F. graminearum spore germination. The fermentation broth and formulation of B. amyloliquefaciens JCK-12 strain reduced the disease incidence of FHB in wheat. Furthermore, co-application of B. amyloliquefaciens JCK-12 and chemical fungicides resulted in synergistic in vitro antifungal effects and significant disease control efficacy against FHB under greenhouse and field conditions, suggesting that B. amyloliquefaciens JCK-12 has a strong chemosensitizing effect. The synergistic antifungal effect of B. amyloliquefaciens JCK-12 and chemical fungicides in combination may result from the cell wall damage and altered cell membrane permeability in the phytopathogenic fungi caused by the CLP mixtures and subsequent increased sensitivity of F. graminearum to fungicides. In addition, B. amyloliquefaciens JCK-12 showed the potential to reduce trichothecenes mycotoxin production. The results of this study indicate that B. amyloliquefaciens JCK-12 could be used as an available biocontrol agent or as a chemosensitizer to chemical fungicides for controlling FHB disease and as a strategy for preventing the contamination of harvested crops with mycotoxins. PMID:29230232

In vitro anti-tubulin effects of mebendazole and fenbendazole on canine glioma cells.

PubMed

Lai, S R; Castello, S A; Robinson, A C; Koehler, J W

2017-12-01

Benzimidazole anthelmintics have reported anti-neoplastic effects both in vitro and in vivo. The purpose of this study was to evaluate the in vitro chemosensitivity of three canine glioma cell lines to mebendazole and fenbendazole. The mean inhibitory concentration (IC 50 ) (±SD) obtained from performing the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay after treating J3T, G06-A, and SDT-3G cells for 72 h with mebendazole were 0.030 ± 0.003, 0.080 ± 0.015 and 0.030 ± 0.006 μM respectively, while those for fenbendazole were 0.550  ± 0.015, 1.530 ± 0.159 and 0.690 ± 0.095 μM; treatment of primary canine fibroblasts for 72 h at IC 50 showed no significant effect. Immunofluorescence studies showed disruption of tubulin after treatment. Mebendazole and fenbendazole are cytotoxic in canine glioma cell lines in vitro and may be good candidates for treatment of canine gliomas. Further in vivo studies are required. © 2017 John Wiley & Sons Ltd.

The Role of Ca2+ and BK Channels of Locus Coeruleus (LC) Neurons as a Brake to the CO2 Chemosensitivity Response of Rats.

PubMed

Imber, Ann N; Patrone, Luis G A; Li, Ke-Yong; Gargaglioni, Luciane H; Putnam, Robert W

2018-06-15

The cellular mechanisms by which LC neurons respond to hypercapnia are usually attributed to an "accelerator" whereby hypercapnic acidosis causes an inhibition of K + channels or activation of Na + and Ca +2 channels to depolarize CO 2 -sensitive neurons. Nevertheless, it is still unknown if this "accelerator" mechanism could be controlled by a brake phenomenon. Whole-cell patch clamping, fluorescence imaging microscopy and plethysmography were used to study the chemosensitive response of the LC neurons. Hypercapnic acidosis activates L-type Ca 2+ channels and large conductance Ca-activated K + (BK) channels, which function as a "brake" on the chemosensitive response of LC neurons. Our findings indicate that both Ca 2+ and BK currents develop over the first 2 weeks of postnatal life in rat LC slices and that this brake pathway may cause the developmental decrease in the chemosensitive firing rate response of LC neurons to hypercapnic acidosis. Inhibition of this brake by paxilline (BK channel inhibitor) returns the magnitude of the chemosensitive firing rate response from LC neurons in rats older than P10 to high values similar to those in LC neurons from younger rats. Inhibition of BK channels in LC neurons by bilateral injections of paxilline into the LC results in a significant increase in the hypercapnic ventilatory response of adult rats. Our findings indicate that a BK channel-based braking system helps to determine the chemosensitive respiratory drive of LC neurons and contributes to the hypercapnic ventilatory response. Perhaps, abnormalities of this braking system could result in hypercapnia-induced respiratory disorders and panic responses. Copyright © 2018 IBRO. Published by Elsevier Ltd. All rights reserved.

Use of chemosensitization to overcome fludioxonil resistance in Penicillium expansum

USDA-ARS?s Scientific Manuscript database

Penicillium expansum mutants (FR2 and FR3) resistant to fludioxonil, a phenylpyrrole fungicide, became susceptible through chemosensitization mediated by natural phenolics. Increased sensitivity of FR3 to oxidizing agents, compared to its parental strain (W2), indicated the oxidative stress respons...

Augmenting the efficacy of fungal and mycotoxin control via chemosensitization

USDA-ARS?s Scientific Manuscript database

Antimycotic chemosensitization could serve as an effective method for control of fungal pathogens. In a chemo-biological platform to enhance antimycotic susceptibility of fungi or to overcome fungal tolerance to conventional antimycotic agents, the model yeast S. cerevisiae could be a functional too...

Signalling and chemosensitivity assays in melanoma: is mutated status a prerequisite for targeted therapy?

PubMed

Passeron, Thierry; Lacour, Jean-Philippe; Allegra, Maryline; Ségalen, Coralie; Deville, Anne; Thyss, Antoine; Giacchero, Damien; Ortonne, Jean-Paul; Bertolotto, Corine; Ballotti, Robert; Bahadoran, Philippe

2011-12-01

Selection for targeted therapies in melanoma is currently based on the search for mutations in selected genes. We aimed at evaluating the interest of signalling and chemosensitivity studies in addition to genotyping for assessing the best suitable treatment in an individual patient. We extracted genomic DNA and melanoma cells from tumor tissue of a skin metastasis of a 17-year-old woman with stage IV melanoma progressing despite three successive lines of treatment. Despite the absence of mutation in BRAF, NRAS cKIT, the MAPK pathway was activated and a significant response to sorafenib, a mitogen-activated protein kinase (MAPK)/RAF inhibitor, was found in signalling and chemosensitivity assays. A treatment combining sorafenib and dacarbazine produced a partial response for 9 months, with marked necrosis in some lesions. Chemosensitivity assays and signalling pathway studies could be of great value in addition to genotyping for assessing the most appropriate treatment in melanoma. © 2011 John Wiley & Sons A/S.

A Whole Cell Pathway Screen Reveals Seven Novel Chemosensitizers to Combat Chloroquine Resistant Malaria

PubMed Central

Ch'ng, Jun-Hong; Mok, Sachel; Bozdech, Zbynek; Lear, Martin James; Boudhar, Aicha; Russell, Bruce; Nosten, Francois; Tan, Kevin Shyong-Wei

2013-01-01

Due to the widespread prevalence of resistant parasites, chloroquine (CQ) was removed from front-line antimalarial chemotherapy in the 1990s despite its initial promise of disease eradication. Since then, resistance-conferring mutations have been identified in transporters such as the PfCRT, that allow for the efflux of CQ from its primary site of action, the parasite digestive vacuole. Chemosensitizing/chemoreversing compounds interfere with the function of these transporters thereby sensitizing parasites to CQ once again. However, compounds identified thus far have disappointing in vivo efficacy and screening for alternative candidates is required to revive this strategy. In this study, we propose a simple and direct means to rapidly screen for such compounds using a fluorescent-tagged CQ molecule. When this screen was applied to a small library, seven novel chemosensitizers (octoclothepin, methiothepin, metergoline, loperamide, chlorprothixene, L-703,606 and mibefradil) were quickly elucidated, including two which showed greater potency than the classical chemosensitizers verapamil and desipramine. PMID:23615863

miR-129 inhibits tumor growth and potentiates chemosensitivity of neuroblastoma by targeting MYO10.

PubMed

Wang, Xiqian; Li, Jing; Xu, Xiao; Zheng, Jiachun; Li, Qingbo

2018-07-01

Although the treatment strategies for neuroblastoma (NB) develop rapidly, a considerable number of patients could not benefit from chemotherapy. Here, we revealed a miR-129-MYO10 axis that regulated neuroblastoma growth and chemosensitivity. Mechanistically, MYO10 was up-regulated in neuroblastoma tissues and associated with poor overall survival. While overexpression of MYO10 enhanced tumor growth, genetic inhibition of MYO10 led to growth-inhibitory and chemopotentiating effects in neuroblastoma. MYO10 was further identified as a target of miR-129. Our data showed that miR-129 down-regulated MYO10 expression and subsequently suppressed cell growth. Re-expression of MYO10 significantly rescued miR129-mediated proliferation repression and chemosensitivity. In conclusion, our results demonstrated that miR-129 inhibited neuroblastoma growth and potentiated chemosensitivity by targeting MYO10, which may represent promising targets and rational therapeutic options for neuroblastoma. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

Implication from thyroid function decreasing during chemotherapy in breast cancer patients: chemosensitization role of triiodothyronine

PubMed Central

2013-01-01

Background Thyroid hormones have been shown to regulate breast cancer cells growth, the absence or reduction of thyroid hormones in cells could provoke a proliferation arrest in G0-G1 or weak mitochondrial activity, which makes cells insensitive to therapies for cancers through transforming into low metabolism status. This biological phenomenon may help explain why treatment efficacy and prognosis vary among breast cancer patients having hypothyroid, hyperthyroid and normal function. Nevertheless, the abnormal thyroid function in breast cancer patients has been considered being mainly caused by thyroid diseases, few studied influence of chemotherapy on thyroid function and whether its alteration during chemotherapy can influence the respose to chemotherapy is still unclear. So, we aimed to find the alterations of thyroid function and non-thyroidal illness syndrome (NTIS) prevalence druing chemotherapy in breast cancer patients, and investigate the influence of thyroid hormones on chemotherapeutic efficacy. Methods Thyroid hormones and NTIS prevalence at initial diagnosis and during chemotherapy were analyzed in 685 breast diseases patients (369 breast cancer, 316 breast benign lesions). The influence of thyroid hormones on chemotherapeutic efficacy was evaluated by chemosensitization test, to compare chemotherapeutic efficacy between breast cancer cells with chemotherapeutics plus triiodothyronine (T3) and chemotherapeutics only. Results In breast cancer, NTIS prevalence at the initial diagnosis was higher and increased during chemotherapy, but declined before the next chemotherapeutic course. Thyroid hormones decreased signigicantly during chemotherapy. T3 can enhance the chemosensitivity of MCF-7 to 5-Fu and taxol, with progression from G0-G1 phase to S phase. The similar chemosensitization role of T3 were found in MDA-MB-231. We compared chemotherapeutic efficacy among groups with different usage modes of T3, finding pretreatment with lower dose of T3, using higher dose of T3 together with 5-Fu or during chemotherapy with 5-Fu were all available to achieve chemosensitization, but pretreatment with lower dose of T3 until the end of chemotherapy may be a safer and more efficient therapy. Conclusions Taken together, thyroid hormones decreasing during chemotherapy was found in lots of breast cancer patients. On the other hand, thyroid hormones can enhance the chemotherapeutic efficacy through gatherring tumor cells in actively proliferating stage, which may provide a new adjuvant therapy for breast cancer in furture, especially for those have hypothyroidism during chemotherapy. PMID:23829347

SPIN1, negatively regulated by miR-148/152, enhances Adriamycin resistance via upregulating drug metabolizing enzymes and transporter in breast cancer.

PubMed

Chen, Xu; Wang, Ya-Wen; Gao, Peng

2018-05-09

Spindlin1 (SPIN1), a protein highly expressed in several human cancers, has been correlated with tumorigenesis and development. Alterations of drug metabolizing enzymes and drug transporters are major determinants of chemoresistance in tumor cells. However, whether the metabolizing enzymes and transporters are under the control of SPIN1 in breast cancer chemoresistance has not yet been defined. SPIN1 expression in breast cancer cells and tissues was detected by quantitative real-time PCR (qRT-PCR) and immunohistochemistry. Chemosensitivity assays in vitro and in vivo were performed to determine the effect of SPIN1 on Adriamycin resistance. Downstream effectors of SPIN1 were screened by microarray and confirmed by qRT-PCR and Western blot. Luciferase assay and Western blot were used to identify miRNAs regulating SPIN1. We showed that SPIN1 was significantly elevated in drug-resistant breast cancer cell lines and tissues, compared with the chemosensitive ones. SPIN1 enhanced Adriamycin resistance of breast cancer cells in vitro, and downregulation of SPIN1 by miRNA could decrease Adriamycin resistance in vivo. Mechanistically, drug metabolizing enzymes and transporter CYP2C8, UGT2B4, UGT2B17 and ABCB4 were proven to be downstream effectors of SPIN1. Notably, SPIN1 was identified as a direct target of the miR-148/152 family (miR-148a-3p, miR-148b-3p and miR-152-3p). As expected, miR-148a-3p, miR-148b-3p or miR-152-3p could increase Adriamycin sensitivity in breast cancer cells in vitro. Moreover, high expression of SPIN1 or low expression of the miR-148/152 family predicted poorer survival in breast cancer patients. Our results establish that SPIN1, negatively regulated by the miR-148/152 family, enhances Adriamycin resistance in breast cancer via upregulating the expression of drug metabolizing enzymes and drug transporter.

Synergism of antifungal activity between mitochondrial respiration inhibitors and kojic acid

USDA-ARS?s Scientific Manuscript database

Co-application of certain types of compounds with conventional antimicrobial drugs results in the enhancement of efficacy of drugs through a mechanism termed chemosensitization. We show that kojic acid (KA), a natural product, is a potent chemosensitizer to complex III inhibitors of mitochondrial re...

CHEMOSENSITIZATION BY A NON-APOPTOGENIC HEAT SHOCK PROTEIN 70-BINDING APOPTOSIS INDUCING FACTOR MUTANT

EPA Science Inventory

Chemosensitization by a non-apoptogenic heat shock protein 70-binding apoptosis inducing factor mutant

Abstract
HSP70 inhibits apoptosis by neutralizing the caspase activator Apaf-1 and by interacting with apoptosis inducing factor (AIF), a mitochondrial flavoprotein wh...

Effect of extracellular acid–base disturbances on the intracellular pH of neurones cultured from rat medullary raphe or hippocampus

PubMed Central

Bouyer, Patrice; Bradley, Stefania Risso; Zhao, Jinhua; Wang, Wengang; Richerson, George B; Boron, Walter F

2004-01-01

Previous reports suggest that an important characteristic of chemosensitive neurones is an unusually large change of steady-state intracellular pH in response to a change in extracellular pH (ΔpHi/ΔpHo). To determine whether such a correlation exists between neurones from the medullary raphe (a chemosensitive brain region) and hippocampus (a non-chemosensitive region), we used BCECF to monitor pHi in cultured neurones subjected to extracellular acid–base disturbances. In medullary raphe neurones, respiratory acidosis (5% → 9% CO2) caused a rapid fall in pHi (ΔpHi ∼0.2) with no recovery and a large ΔpHi/ΔpHo of 0.71. Hippocampal neurones had a similar response, but with a slightly lower ΔpHi/ΔpHo (0.59). We further investigated a possible link between pHi regulation and chemosensitivity by following the pHi measurements on medullary raphe neurones with an immunocytochemistry for tryptophan hydroxylase (a marker of serotonergic neurones). We found that the ΔpHi/ΔpHo of 0.69 for serotonergic neurones (which are stimulated by acidosis) was not different from either the ΔpHi/ΔpHo of 0.75 for non-serotonergic neurones (most of which are not chemosensitive), or from the ΔpHi/ΔpHo of hippocampal neurones. For both respiratory alkalosis (5% → 3% CO2) and metabolic alkalosis (22 mm → 35 mm HCO3−), ΔpHi/ΔpHo was 0.42–0.53 for all groups of neurones studied. The only notable difference between medullary raphe and hippocampal neurones was in response to metabolic acidosis (22 mm → 14 mm HCO3−), which caused a large pHi decrease in ∼80% of medullary raphe neurones (ΔpHi/ΔpHo = 0.71), but relatively little pHi decrease in 70% of the hippocampal neurones (ΔpHi/ΔpHo = 0.09). Our comparison of medullary raphe and hippocampal neurones indicates that, except in response to metabolic acidosis, the neurones from the chemosensitive region do not have a uniquely high ΔpHi/ΔpHo. Moreover, regardless of whether neurones were cultured from the chemosensitive or the non-chemosensitive region, pHi did not recover during any of the acid–base stresses. PMID:15194736

Predictive markers of chemoresistance in advanced stages epithelial ovarian carcinoma.

PubMed

Bonneau, Claire; Rouzier, Roman; Geyl, Caroline; Cortez, Annie; Castela, Mathieu; Lis, Raphael; Daraï, Emile; Touboul, Cyril

2015-01-01

DNA repair mechanisms, environment-mediated drug resistance and cancer initiating cells (CIC) are three major research concepts that can explain the chemoresistance of epithelial ovarian cancer (EOC). The objective was to test if changes in the expression of potential markers associated with drug resistance before and after chemotherapy would correlate with platinum resistance, defined as a recurrence within the first year after chemotherapy cessation, and with survival, in advanced EOC. We included 32 patients with stage IIIC-IV EOC who underwent laparoscopy to evaluate the extent of carcinomatosis, neoadjuvant chemotherapy (carboplatin/taxol) and interval surgery. Biopsies taken during the initial laparoscopies and interval surgeries were evaluated using immunohistochemistry for the expression of 7 proteins: CD117, CD44 and ALDH1 to evaluate CIC; IL-6, IL-8 and BMP2 to evaluate environment-mediated drug resistance; and ERCC1 to evaluate DNA repair. Expression measurements were correlated with platin resistance and survival. The markers' relevance was confirmed in vitro using chemoresistance tests and flow cytometric measurements of the proportion of CD44+ cells. 17 patients were chemoresistant and 15 patients were chemosensitive. We observed increases in CD44, IL-6 and ERCC1 expression and stable ALDH1, CD117, IL-8, and BMP2 expression. Reduced expression of cancer initiating cell markers and increased expression of environment-mediated drug resistance markers were associated with poor prognosis. We also demonstrated that CD44+ cells had survival advantages in vitro. Changes in CD44 and IL-8 expression on tumor cells appeared to correlate with overall survival and should be further tested as predictors of chemoresistance using larger cohort. Copyright © 2014 Elsevier Inc. All rights reserved.

Effect of Procyanidin-rich Extract from Natural Cocoa Powder on Cellular Viability, Cell Cycle Progression, and Chemoresistance in Human Epithelial Ovarian Carcinoma Cell Lines

PubMed Central

Taparia, Shruti; Khanna, Aparna

2016-01-01

Background: Over the last 400 years, cocoa and chocolate have been described as having potential medicinal value, being consumed as a beverage or eaten as food. Concentration–dependant, antiproliferation, and cytotoxic effects of some of their polyphenolic constituents have been demonstrated against various cancers. Such an effect remains to be demonstrated in ovarian cancer Objective: To investigate the effect of cocoa procyanidins against ovarian cancer in vitro using OAW42 and OVCAR3 cell lines. Materials and Methods: Cocoa procyanidins were extracted and enriched from non alkalized cocoa powder. The polyphenolic content and antioxidant activity were determined. Effect on cell viability was determined after the treatment with ≤1000 μg/mL cocoa procyanidin-rich extract on OAW42 and OVCAR3 and normal human dermal fibroblasts. Similarly, chemosensitization effect was determined by pretreating cancer cell lines with extract followed by doxorubicin hydrochloride treatment. The effect of treatment on cell cycle and P-glycoprotein (P-gp) expression was determined using flow cytometry. Results: The cocoa extract showed high polyphenolic content and antioxidant activity. Treatment with extract caused cytotoxicity and chemosensitization in OAW42 and OVCAR3 cell lines. Normal dermal fibroblasts showed an increase in cell viability post treatment with extract. Treatment with extract affected the cell cycle and an increasing percentage of cells in hypodiploid sub-G1/G0 phase was observed. Treatment of OVCAR3 with the extract caused reduction of P-gp expression. Conclusion: Cocoa procyanidins were found to be selectively cytotoxic against epithelial ovarian cancer, interfered with the normal cell cycle and sensitized cells to subsequent chemotherapeutic treatment. Chemosensitization was found to be associated with P-gp reduction in OVCAR3 cells. SUMMARY Among the naturally occurring flavonoids, procyanidins have been shown to be effective against cancersNon alkalized cocoa powder is one of the richest sources of procyanidinsCocoa procyanidin-rich extract (CPRE) caused cytotoxicity and chemosensitization in ovarian carcinoma cell lines OAW42 and OVCAR3CPRE affected normal cell cycle progressionCPRE also downregulated P-glycoprotein, which mediates chemoresistance in multidrug-resistant OVCAR3 cell line. Abbreviations used: P-gp: P-glycoprotein, CPRE: Cocoa procyanidin rich extract, DMAC: 4-dimethylaminocinnamaldehyde, DPPH: Diphenylpicrylhydrazyl, ABTS: 2,2’;-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid), PI: Propidium iodide, FITC: Fluorescein isothiocyanate, MTT: 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, TLC: Thin layer chromatography, HPTLC: High-performance thin layer chromatography. PMID:27279694

[Cell cycle and apoptosis mechanisms implicated in intravesical chemotherapy resistances in superficial bladder cancer].

PubMed

Burgués Gasión, J P; Pontones Moreno, J L; Vera Donoso, C D; Jiménez Cruz, J F; Ozonas Moragues, M

2005-10-01

It is well documented the effectiveness of intravesical chemotherapy following transurethral resection to prevent recurrences of superficial bladder cancer. But it is also known that efficacy may be limited by tumour cell resistance to one or several of the drugs available for instillation. In addition to the genetically determined unicellular mechanisms classically described in the literature such as glycoprotein P-170 expression (mdr-1), overexpression of Bcl-2 or glutation S-transferase activity, it has been recently shown that multicellular mechanisms may also be involved in drug resistance. Multicellular resistance can only be demonstrated in three-dimensional cultures and fails to be shown in monolayers or cell suspensions. This is explained by the fact that cell-to-cell and cell-to-stroma adhesion limits drug penetration and by the variable susceptibility to cytotoxicity determined by oxygen and tissue proliferation gradients. A better understanding of the molecular mechanisms involved in drug resistance is necessary to increase intravesical chemotherapy effectiveness. Current research includes improving drug penetration, searching resistance reversing agents and developing in vitro chemosensitivity tests to identify drug resistance.

Aspirin inhibits the SHH/GLI1 signaling pathway and sensitizes malignant glioma cells to temozolomide therapy

PubMed Central

Li, Ziwei; Lin, Lin; Meng, Xiangqi; Han, Bo; Wang, Ruijia; Wu, Pengfei; Li, Jianlong; Cai, Jinquan; Jiang, Chuanlu

2017-01-01

Aberrant activation of sonic hedgehog (SHH)/glioma-associated oncogene homolog 1 (GLI1) pathway plays an important role in the tumorigenicity of malignant glioma cells and resistance to temozolomide (TMZ). Here we investigated the aspirin's antineoplastic molecular route by targeting SHH/GLI1 pathway and examined the feasibility of aspirin combined with TMZ therapy. Western blot and quantitative real-time polymerase chain reaction (qRT-PCR) revealed that the activity of the SHH/GLI1 pathway was strongly inhibited by aspirin. Aspirin acted as the glioma growth-inhibitory and pro-apoptosis roles by inhibiting the SHH/GLI1 pathway and reprogramming the epithelial to mesenchymal transition (EMT). The immunofluorescence assay showed aspirin could prevent the nuclear translocation of GLI1 to inhibit its transcriptional regulation. The stable lentiviral overexpression of GLI1 reversed the DNA double strand breaks (DSBs) caused by the GANT61 and TMZ. Furthermore, aspirin combined with TMZ enhanced chemosensitivity and GLI1-induced chemoprotection was partly blocked by aspirin in vitro and in vivo. Collectively, aspirin has a therapeutic potential for SHH/GLI1 targeted therapy against glioma cells. Acquired activation of GLI1 protects glioma cells against TMZ therapy. Impairment of DNA DSBs repair activity might be involved in the route of aspirin-induced chemosensitivity. Combined aspirin with TMZ may be a promising strategy against malignant glioma. PMID:28446712

Aspirin inhibits the SHH/GLI1 signaling pathway and sensitizes malignant glioma cells to temozolomide therapy.

PubMed

Ming, Jianguang; Sun, Bo; Li, Ziwei; Lin, Lin; Meng, Xiangqi; Han, Bo; Wang, Ruijia; Wu, Pengfei; Li, Jianlong; Cai, Jinquan; Jiang, Chuanlu

2017-04-01

Aberrant activation of sonic hedgehog (SHH)/glioma-associated oncogene homolog 1 (GLI1) pathway plays an important role in the tumorigenicity of malignant glioma cells and resistance to temozolomide (TMZ). Here we investigated the aspirin's antineoplastic molecular route by targeting SHH/GLI1 pathway and examined the feasibility of aspirin combined with TMZ therapy. Western blot and quantitative real-time polymerase chain reaction (qRT-PCR) revealed that the activity of the SHH/GLI1 pathway was strongly inhibited by aspirin. Aspirin acted as the glioma growth-inhibitory and pro-apoptosis roles by inhibiting the SHH/GLI1 pathway and reprogramming the epithelial to mesenchymal transition (EMT). The immunofluorescence assay showed aspirin could prevent the nuclear translocation of GLI1 to inhibit its transcriptional regulation. The stable lentiviral overexpression of GLI1 reversed the DNA double strand breaks (DSBs) caused by the GANT61 and TMZ. Furthermore, aspirin combined with TMZ enhanced chemosensitivity and GLI1-induced chemoprotection was partly blocked by aspirin in vitro and in vivo . Collectively, aspirin has a therapeutic potential for SHH/GLI1 targeted therapy against glioma cells. Acquired activation of GLI1 protects glioma cells against TMZ therapy. Impairment of DNA DSBs repair activity might be involved in the route of aspirin-induced chemosensitivity. Combined aspirin with TMZ may be a promising strategy against malignant glioma.

Enhancement of antimycotic activity of amphotericin B by targeting the oxidative stress response of Candida and Cryptococcus with natural dihydroxybenzaldehydes

USDA-ARS?s Scientific Manuscript database

Many yeast pathogens of humans have become resistant to currently available drugs. Certain types of compounds can increase efficacy of antimycotic drugs through a process termed chemosensitization. Chemosensitizing efficacy was determined in Candida albicans, C. krusei, C. tropicalis and Cryptococcu...

Increasing brain serotonin corrects CO2 chemosensitivity in methyl-CpG-binding protein 2 (Mecp2)-deficient mice

PubMed Central

Toward, Marie A.; Abdala, Ana P.; Knopp, Sharon J.; Paton, Julian F. R.; Bissonnette, John M.

2013-01-01

Mice deficient in the transcription factor methyl-CpG-binding protein 2 (Mecp2), a mouse model of Rett syndrome, display reduced CO2 chemosensitivity, which may contribute to their breathing abnormalities. In addition, patients with Rett syndrome and male mice that are null for Mecp2 show reduced levels of brain serotonin (5-HT). Serotonin is known to play a role in central chemosensitivity, and we hypothesized that increasing the availability of 5-HT in this mouse model would improve their respiratory response to CO2. Here we determined the apnoeic threshold in heterozygous Mecp2-deficient female mice and examined the effects of blocking 5-HT reuptake on the CO2 response in Mecp2-null male mice. Studies were performed in B6.129P2(C)-Mecp2τm1.1Bird null males and heterozygous females. In an in situ preparation, seven of eight Mecp2-deficient heterozygous females showed arrest of phrenic nerve activity when arterial CO2 was lowered to 3%, whereas the wild-types maintained phrenic nerve amplitude at 53 ± 3% of maximal. In vivo plethysmography studies were used to determine CO2 chemosensitivity in null males. These mice were exposed sequentially to 1, 3 and 5% CO2. The percentage increase in minute ventilation in response to increased inspired CO2 was less in Mecp2−/y than in Mecp2+/y mice. Pretreatment with citalopram, a selective 5-HT reuptake inhibitor (2.5 mg kg−1 I.P.), 40 min prior to CO2 exposure, in Mecp2−/y mice resulted in an improvement in CO2 chemosensitivity to wild-type levels. These results suggest that decreased 5-HT in Mecp2-deficient mice reduces CO2 chemosensitivity, and restoring 5-HT levels can reverse this effect. PMID:23180809

Anticancer effects of deproteinized asparagus polysaccharide on hepatocellular carcinoma in vitro and in vivo.

PubMed

Xiang, Jianfeng; Xiang, Yanjie; Lin, Shengming; Xin, Dongwei; Liu, Xiaoyu; Weng, Lingling; Chen, Tao; Zhang, Minguang

2014-04-01

Hepatocellular carcinoma (HCC) is one of the most aggressive malignancies in the world whose chemoprevention became increasingly important in HCC treatment. Although the anticancer effects of asparagus constituents have been investigated in several cancers, its effects on hepatocellular carcinoma have not been fully studied. In this study, we investigated the anticancer effects of the deproteinized asparagus polysaccharide on the hepatocellular carcinoma cells using the in vitro and in vivo experimental model. Our data showed that deproteinized asparagus polysaccharide might act as an effective inhibitor on cell growth in vitro and in vivo and exert potent selective cytotoxicity against human hepatocellular carcinoma Hep3B and HepG2 cells. Further study showed that it could potently induce cell apoptosis and G2/M cell cycle arrest in the more sensitive Hep3B and HepG2 cell lines. Moreover, deproteinized asparagus polysaccharide potentiated the effects of mitomycin both in vitro and in vivo. Mechanistic studies revealed that deproteinized asparagus polysaccharide might exert its activity through an apoptosis-associated pathway by modulating the expression of Bax, Bcl-2, and caspase-3. In conclusion, deproteinized asparagus polysaccharide exhibited significant anticancer activity against hepatocellular carcinoma cells and could sensitize the tumoricidal effects of mitomycin, indicating that it is a potential therapeutic agent (or chemosensitizer) for liver cancer therapy.

Expression of mismatch repair gene PMS2 in nasopharyngeal carcinoma and regulation by glycogen synthase kinase-3β in vivo and in vitro.

PubMed

Fang, Jugao; Lei, Wenbin; Huang, Xiaoming; Li, Pingdong; Chen, Xiaohong; Zhu, Xiaolin; Wen, Weiping; Li, Huabin

2012-02-01

To evaluate the expression of mismatch repair gene PMS2 in human nasopharyngeal carcinoma (NPC) tissues and evaluate the effect of glycogen synthase kinase (GSK)-3β on PMS2 production in vivo and in vitro. The expression of PMS2 and inactivated phosphorylated GSK-3β(s9) was examined by immunohistochemical staining in 25 NPC tissues and the relation was determined by correlation analysis. The effect of GSK-3β transfection in CNE-2 cells on PMS2 production as well as cell apoptosis and chemosensitization were evaluated using small interference RNA (siRNA), immunoblotting and flow cytometric analysis in vitro. The expression of inactivated phosphorylated GSK-3β(s9) was found to negative correlated with PMS2 in vivo. And transfected GSK-3β was found to be able to enhance PMS2 production, and increase cell apoptosis in CNE-2 cells in combination with cisplatin administration in vitro. Inactivation of GSK-3β might be important for NPC tumorgenesis through negatively regulating PMS2 production, and enhanced PMS2 production by GSK-3β is beneficial for understanding the NPC tumorgenesis and developing potential strategy for future therapy. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Decorin in human oral cancer: A promising predictive biomarker of S-1 neoadjuvant chemosensitivity

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

Kasamatsu, Atsushi, E-mail: kasamatsua@faculty.chiba-u.jp; Department of Dentistry and Oral–Maxillofacial Surgery, Chiba University Hospital, Chiba 260-8670; Uzawa, Katsuhiro, E-mail: uzawak@faculty.chiba-u.jp

Highlights: • DCN is significantly up-regulated in chemoresistant cancer cell lines. • DCN is a key regulator for chemoresistant mechanisms in vitro and in vivo. • DCN predicts the clinical responses to S-1 NAC for patients with oral cancer. - Abstract: We reported previously that decorin (DCN) is significantly up-regulated in chemoresistant cancer cell lines. DCN is a small leucine-rich proteoglycan that exists and functions in stromal and epithelial cells. Accumulating evidence suggests that DCN affects the biology of several types of cancer by directly/indirectly targeting the signaling molecules involved in cell growth, survival, metastasis, and angiogenesis, however, the molecularmore » mechanisms of DCN in chemoresistance and its clinical relevance are still unknown. Here we assumed that DCN silencing cells increase chemosusceptibility to S-1, consisted of tegafur, prodrug of 5-fluorouracil. We first established DCN knockdown transfectants derived from oral cancer cells for following experiments including chemosusceptibility assay to S-1. In addition to the in vitro data, DCN knockdown zenografting tumors in nude mice demonstrate decreasing cell proliferation and increasing apoptosis with dephosphorylation of AKT after S-1 chemotherapy. We also investigated whether DCN expression predicts the clinical responses of neoadjuvant chemotherapy (NAC) using S-1 (S-1 NAC) for oral cancer patients. Immunohistochemistry data in the preoperative biopsy samples was analyzed to determine the cut-off point for status of DCN expression by receiver operating curve analysis. Interestingly, low DCN expression was observed in five (83%) of six cases with complete responses to S-1 NAC, and in one (10%) case of 10 cases with stable/progressive disease, indicating that S-1 chemosensitivity is dramatically effective in oral cancer patients with low DCN expression compared with high DCN expression. Our findings suggest that DCN is a key regulator for chemoresistant mechanisms, and is a predictive immunomarker of the response to S-1 NAC and patient prognosis.« less

A new agent developed by biotransformation of polyphyllin VII inhibits chemoresistance in breast cancer

PubMed Central

Zhang, Liang; Mao, Ai-Qin; Wei, Juan; Liu, De-Quan; Shi, Gui-Yang; Ma, Xin

2016-01-01

Biotransformation by the endophytes of certain plants changes various compounds, and this ‘green’ chemistry becomes increasingly important for finding new products with pharmacological activity. In this study, polyphyllin VII (PPL7) was biotransformed by endophytes from the medicinal plant Paris polyphylla Smith, var. yunnanensis. This produced a new compound, ZH-2, with pharmacological activity in vitro and in vivo. ZH-2 was more potent than PPL7 in selectively killing more chemoresistant than chemosensitive breast cancer cells. ZH-2 also re-sensitized chemoresistant breast cancer cells, as evidenced by the improved anti-cancer activity of commonly-used chemotherapeutic agent in vitro, in vivo, and in clinical samples. This anti-chemoresistance effect of ZH-2 was associated with inhibiting the epithelial-mesenchymal transition (EMT) pathway. Taken together, our findings are the first one to link biotransformation with a biomedicine. The results provide insights into developing new pharmacologically-active agents via biotransformation by endophytes. PMID:26701723

Effect of Maturation of the Magnitude of Mechanosensitive and Chemosensitive Reflexes in the Premature Human Esophagus

PubMed Central

Jadcherla, Sudarshan Rao; Hoffmann, Raymond G.; Shaker, Reza

2014-01-01

Objectives To investigate the effect of esophageal mechanosensitive and chemosensitive stimulation on the magnitude and recruitment of peristaltic reflexes and upper esophageal sphincter (UES)-contractile reflex in premature infants. Study design Esophageal manometry and provocation testing were performed in the same 18 neonates at 33 and 36 weeks postmenstrual age (PMA). Mechanoreceptor and chemoreceptor stimulation were performed using graded volumes of air, water, and apple juice (pH 3.7), respectively. The frequency and magnitude of the resulting esophago-deglutition response (EDR) or secondary peristalsis (SP), and esophago-UES-contractile reflex (EUCR) were quantified. Results Threshold volumes to evoke EDR, SP, or EUCR were similar. The recruitment and magnitude of SP and EUCR increased with volume increments of air and water in either study (P < .05). However, apple juice infusions resulted in increased recruitment of EDR in the 33 weeks group (P < .05), and SP in the 36 weeks group (P < .05). The magnitude of EUCR was also volume responsive (all media, P < .05), and significant differences between media were noted (P < .05). At maximal stimulation (1 mL, all media), sensory-motor characteristics of peristaltic and EUCR reflexes were different (P < .05) between media and groups. Conclusions Mechano- and chemosensitive stimuli evoke volume-dependent specific peristaltic and UES reflexes at 33 and 36 weeks PMA. The recruitment and magnitude of these reflexes are dependent on the physicochemical properties of the stimuli in healthy premature infants. PMID:16860132

Comparative study of the in vitro activity of various antifungal drugs against Scedosporium spp. in aerobic and hyperbaric atmosphere versus normal atmosphere.

PubMed

Farina, C; Marchesi, G; Passera, M; Diliberto, C; Russello, G

2012-06-01

Scedosporium spp. have been observed with increasing frequency over the last decade in immunocompromised patients and trauma patients. This mould is often multi-drug resistant and its mortality rate remains very high. The primary goal of this study was to obtain data concerning the in vitro susceptibility of 13 Scedosporium strains comparing the in vitro incubation in aerobic versus hyperbaric conditions. Chemosensitivity of thirteen Scedosporium strains was evaluated after a 72h-incubation in a normoxic (21% O2) normobaric (1 ATA) atmosphere versus a hyperoxic (100% O2) hyperbaric (2-3 ATA), and after a re-incubation at room temperature for an additional 72h. All S. apiospermum and S. prolificans strains showed no growth after incubation in hyperbaric hyperoxic atmosphere. However, when plates were then maintained at room temperature in aerobic conditions, growth was systematically observed from 36 to 96h, and Minimal inhibitory concentration (MIC) values were the same obtained after incubation in aerobic conditions. These results suggest impressive in vitro fungistatic activity of the hyperoxic hyperbaric atmosphere, even if its effect is strictly time-dependent. This preliminary in vitro study has potential clinical relevance because it focuses on examining in vitro combination therapy using hyperoxic hyperbaric conditions plus a single antifungal agent, rather than using combinations of different antifungal drugs, to potentially increase the antifungal activity. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

[Expression of C-fos in nasopharyngeal carcinoma and the relationship with chemosensitivity and prognosis].

PubMed

Liu, Y T; Zhao, F P; Miao, H B; Fu, S Z; Zhou, S; Zhang, X G; Qin, G

2018-05-01

Objective: To investigate the expression of C-fos in patients with nasopharyngeal carcinoma(NPC), and analyze the relationship between the expression of C-fos and the clinical characteristics, chemosensitivity and prognosis. Method: Clinical and follow-up data of 75 NPC patients was analyzed retrospectively. The expression of C-fos was detected by immunohistochemical assay, and chemosensitivity was detected by ATP bioluminescent anticancer drug sensitivity detection technology. The relationship between them was studied. Result: The expression of C-fos in NPC was statistically higher than that in the control nasopharyngeal mucosa( P <0.001). It was found that C-fos had no statistical relationship with the gender, age, pathologic type, clinical stage of tumor classification, lymph node status, metastasis status and overall stage of NPC patients( P >0.05). NPC had different chemosensitivity with 8 anticancer drugs( P <0.001).There was a significant difference in chemosensitivity of paclitaxel between the high expression of C-fos group and the low expression of C-fos group( P =0.036). The rate of tumor progression was significantly higher in NPC patients with high expression of C-fos than in the low expression group( P =0.014).There was no significant difference in overall survival between the two groups( P =0.076). Conclusion: C-fos is highly expressed in NPC tissues, and the high expression of C-fos in NPC tissues may be related to tumor progression and resistance to paclitaxel. Copyright© by the Editorial Department of Journal of Clinical Otorhinolaryngology Head and Neck Surgery.

Antitumor Agents 293. Non-toxic Dimethyl-4,4′-dimethoxy-5,6,5′,6′-dimethylenedioxybiphenyl-2,2′-dicarboxylate (DDB) Analogs Chemosensitize Multidrug Resistant Cancer Cells to Clinical Anticancer Drugs

PubMed Central

Hung, Hsin-Yi; Ohkoshi, Emika; Goto, Masuo; Bastow, Kenneth F.; Nakagawa-Goto, Kyoko; Lee, Kuo-Hsiung

2012-01-01

Novel dimethyl-4,4′-dimethoxy-5,6,5′,6′-dimethylenedioxybiphenyl-2,2′-dicarboxylate (DDB) analogs were designed and synthesized to improve their chemosensitizing action on KBvin (vincristine resistant nasopharyngeal carcinoma) cells, a multi-drug resistant cell line over-expressing P-glycoprotein (P-gp). Structure-activity relationship analysis showed that aromatic and bulky aliphatic side chains at the 2,2′-positions effectively and significantly sensitized P-gp overexpressing multidrug resistant (MDR) cells to anticancer drugs, such as paclitaxel (TAX), vincristine (VCR), and doxorubicin (DOX). DDB derivatives 16 and 23 showed 5–10 times more effective reversal ability than verapamil (VRP) for TAX and VCR. Analog 6 also exhibited five times greater chemosensitizing effect against DOX than VRP. Importantly, no cytotoxicity was observed by the active DDB analogs against both non-MDR and MDR cells, suggesting that DDB analogs serve as the novel lead compounds for the development of chemosensitizers to overcome MDR phenotype. The mechanism of action studies demonstrated that effective inhibition of P-glycoprotein by DDB analogs dramatically elevated cellular concentration of anticancer drugs. PMID:22612652

End-of-life chemotherapy is associated with poor survival and aggressive care in patients with small cell lung cancer.

PubMed

Zhu, Yingming; Tang, Ke; Zhao, Fen; Zang, Yuanwei; Wang, Xiaodong; Li, Zhenxiang; Sun, Xindong; Yu, Jinming

2018-05-29

Concerns regarding end-of-life (EOL) chemotherapy are being increasingly raised. Tumor chemosensitivity may influence the decision for aggressive chemotherapy near the EOL. Data on EOL chemotherapy in highly chemosensitive tumors, such as small cell lung cancer (SCLC), are scarce. A total of 143 SCLC decedents were consecutively included. Data about clinical factors and treatment modalities were obtained from the electronic medical records. The relationships among EOL chemotherapy, clinical features, overall survival (OS), and aggressive care were investigated. About 64% of patients had chemosensitive disease. In total, 30.8 and 16.1% of patients received EOL chemotherapy within the last 1 and 2 months of life, respectively. Younger age was associated with a higher rate of EOL chemotherapy. We determined that EOL chemotherapy was related to inferior OS not only in the entire group, but also in the chemosensitive subgroup. Furthermore, more intensive care was observed among patients who underwent EOL chemotherapy compared with those who did not. EOL chemotherapy was correlated with shorter survival and more aggressive care in patients with SCLC. More research is needed to develop indications for terminating palliative chemotherapy, to help physicians and patients with their difficult choices.

Respiratory signaling of locus coeruleus neurons during hypercapnic acidosis in the bullfrog, Lithobates catesbeianus.

PubMed

Santin, J M; Hartzler, L K

2013-02-01

The locus coeruleus (LC) in the brainstem senses alterations in CO(2)/pH and influences ventilatory adjustments that restore blood gas values to starting levels in bullfrogs (Lithobates catesbeianus). We hypothesized that neurons of the bullfrog LC are sensitive to changes in CO(2)/pH and that chemosensitive responses are intrinsic to individual neurons. In addition, we hypothesized putative respiratory control neurons of the bullfrog LC would be stimulated by hypercapnic acidosis within physiological ranges of P(CO(2))/pH. 84% of LC neurons depolarized and increased firing rates during exposure to hypercapnic acidosis (HA). A pH dose response curve shows LC neurons from bullfrogs increase firing rates during physiologically relevant CO(2)/pH changes. With chemical synapses blocked, half of chemosensitive neurons lost sensitivity to HA; however, gap junction blockade did not alter chemosensitive responses. Intrinsically chemosensitive neurons increased input resistance during HA. These data demonstrate that majority of neurons within the bullfrog LC elicit robust firing responses during physiological ΔCO(2)/pH, likely enabling adjustment of acid-base balance through breathing. Copyright © 2012 Elsevier B.V. All rights reserved.

Central Respiratory Chemosensitivity and Cerebrovascular CO[subscript 2] Reactivity: A Rebreathing Demonstration Illustrating Integrative Human Physiology

ERIC Educational Resources Information Center

MacKay, Christina M.; Skow, Rachel J.; Tymko, Michael M.; Boulet, Lindsey M.; Davenport, Margie H.; Steinback, Craig D.; Ainslie, Philip N.; Lemieux, Chantelle C. M.; Day, Trevor A.

2016-01-01

One of the most effective ways of engaging students of physiology and medicine is through laboratory demonstrations and case studies that combine 1) the use of equipment, 2) problem solving, 3) visual representations, and 4) manipulation and interpretation of data. Depending on the measurements made and the type of test, laboratory demonstrations…

Synthesis and evaluation of novel N-substituted-6-methoxynaphthalene-2-carboxamides as potential chemosensitizing agents for cancer.

PubMed

Lokhande, Tushar Narendra; Viswanathan, Chelakara Lakshmann; Juvekar, Aarti Shashikant

2008-07-01

A novel class of molecules with structure N-[3-(heteroaryl)propyl]-6-methoxynaphthalene-2-carboxamides 8-13 were synthesized by condensing 6-methoxy-2-naphthoyl chloride 1 with 3-(heteroaryl)propyl amines 2-7. Compounds 8-12 were evaluated in vitro, in P388 murine lymphocytic leukemia cell line (P388) using SRB assay for cytotoxicity and in adriamycin resistant P388 murine lymphocytic leukemia cell line (P388/ADR) using MTT assay for resistant reversal activity. Compounds 8-12 were non-toxic at lower dose of 20 microg/ml, and effectively reversed adriamycin resistance. However, at higher doses (40, 80 microg/ml) they showed significant cytotxicity and hence reversal potency was not determined at these concentrations.

Upregulation of human DNA binding protein A (dbpA) in gastric cancer cells.

PubMed

Wang, Guo-rong; Zheng, Yan; Che, Xiang-ming; Wang, Xin-yang; Zhao, Jia-hui; Wu, Kai-jie; Zeng, Jin; Pan, Chen-en; He, Da-lin

2009-10-01

To determine the effect of human DNA binding protein (dbpA) on the biology of gastric cancer cells. DbpA expression was analyzed by Western blot analysis and immunofluorescence staining in gastric cancer tissues and cell lines. A dbpA-specific small interference (si) RNA was designed and synthesized. Suppressive effect of siRNA on dbpA expression was assessed by real-time RT-PCR. Transwell migration and colony formation assays were used to assess the inhibitory effects of dbpA siRNA on cell invasion and tumorigenesis in vitro. Drug-sensitivity was evaluated using a conventional 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. The expression of dbpA was upregulated in gastric cancer tissues and cell lines as compared to adjacent normal tissues or gastric epithelial cells. siRNA treatment successfully silenced dbpA expression. Silencing of dbpA increased expression of E-cadherin, decreased expression of adenomatous polyposis coli (APC), beta-catenin and cyclin D1, but had no effect on expression of NF-kappaB. Silencing of dbpA also suppressed cell invasion and colony formation of SGC7901 cells, and enhanced their chemosensitivity to 5-fluorouracil. DbpA plays an important role in the pathogenesis and development of gastric cancer, and the process involves E-cadherin, APC, beta-catenin and cyclin D1. Silencing of dbpA might be a novel therapeutic strategy for increasing chemosensitivity to 5-fluorouracil in gastric cancer.

Loss of Smad4 in colorectal cancer induces resistance to 5-fluorouracil through activating Akt pathway.

PubMed

Zhang, B; Zhang, B; Chen, X; Bae, S; Singh, K; Washington, M K; Datta, P K

2014-02-18

Higher frequency of Smad4 inactivation or loss of expression is observed in metastasis of colorectal cancer (CRC) leading to unfavourable survival and contributes to chemoresistance. However, the molecular mechanism of how Smad4 regulates chemosensitivity of CRC is unknown. We evaluated how the loss of Smad4 in CRC enhanced chemoresistance to 5-fluorouracil (5-FU) using two CRC cell lines in vitro and in vivo. Immunoblotting with cell and tumour lysates and immunohistochemical analyses with tissue microarray were performed. Knockdown or loss of Smad4 induced tumorigenicity, migration, invasion, angiogenesis, metastasis, and 5-FU resistance. Smad4 expression in mouse tumours regulated cell-cycle regulatory proteins leading to Rb phosphorylation. Loss of Smad4 activated Akt pathway that resulted in upregulation of anti-apoptotic proteins, Bcl-2 and Bcl-w, and Survivin. Suppression of phosphatidylinositol-3-kinase (PI3K)/Akt pathway by LY294002 restored chemosensitivity of Smad4-deficient cells to 5-FU. Vascular endothelial growth factor-induced angiogenesis in Smad4-deficient cells might also lead to chemoresistance. Low levels of Smad4 expression in CRC tissues correlated with higher levels of Bcl-2 and Bcl-w and with poor overall survival as observed in immunohistochemical staining of tissue microarrays. Loss of Smad4 in CRC patients induces resistance to 5-FU-based therapy through activation of Akt pathway and inhibitors of this pathway may sensitise these patients to 5-FU.

Loss of Smad4 in colorectal cancer induces resistance to 5-fluorouracil through activating Akt pathway

PubMed Central

Zhang, B; Zhang, B; Chen, X; Bae, S; Singh, K; Washington, M K; Datta, P K

2014-01-01

Background: Higher frequency of Smad4 inactivation or loss of expression is observed in metastasis of colorectal cancer (CRC) leading to unfavourable survival and contributes to chemoresistance. However, the molecular mechanism of how Smad4 regulates chemosensitivity of CRC is unknown. Methods: We evaluated how the loss of Smad4 in CRC enhanced chemoresistance to 5-fluorouracil (5-FU) using two CRC cell lines in vitro and in vivo. Immunoblotting with cell and tumour lysates and immunohistochemical analyses with tissue microarray were performed. Results: Knockdown or loss of Smad4 induced tumorigenicity, migration, invasion, angiogenesis, metastasis, and 5-FU resistance. Smad4 expression in mouse tumours regulated cell-cycle regulatory proteins leading to Rb phosphorylation. Loss of Smad4 activated Akt pathway that resulted in upregulation of anti-apoptotic proteins, Bcl-2 and Bcl-w, and Survivin. Suppression of phosphatidylinositol-3-kinase (PI3K)/Akt pathway by LY294002 restored chemosensitivity of Smad4-deficient cells to 5-FU. Vascular endothelial growth factor-induced angiogenesis in Smad4-deficient cells might also lead to chemoresistance. Low levels of Smad4 expression in CRC tissues correlated with higher levels of Bcl-2 and Bcl-w and with poor overall survival as observed in immunohistochemical staining of tissue microarrays. Conclusion: Loss of Smad4 in CRC patients induces resistance to 5-FU-based therapy through activation of Akt pathway and inhibitors of this pathway may sensitise these patients to 5-FU. PMID:24384683

Downregulation of CD147 expression by RNA interference inhibits HT29 cell proliferation, invasion and tumorigenicity in vitro and in vivo.

PubMed

Li, Rui; Pan, Yuqin; He, Bangshun; Xu, Yeqiong; Gao, Tianyi; Song, Guoqi; Sun, Huiling; Deng, Qiwen; Wang, Shukui

2013-12-01

We investigated the effect of CD147 silencing on HT29 cell proliferation and invasion. We constructed a novel short hairpin RNA (shRNA) expression vector pYr-mir30-shRNA. The plasmid was transferred to HT29 cells. The expression of CD147, MCT1 (lactate transporters monocarboxylate transporter 1) and MCT4 (lactate transporters monocarboxylate transporter 4) were monitored by quantitative PCR and western blotting, respectively. The MMP-2 (matrix metalloproteinase-2) and MMP-9 (matrix metalloproteinase-9) activities were determined by gelatin zymography assay, while the intracellular lactate concentration was determined by the lactic acid assay kit. WST-8 assay was used to determine the HT29 cell proliferation and the chemosensitivity. Invasion assay was used to determine the invasion of HT29 cells. In addition, we established a colorectal cancer model, and detected CD147 expression in vivo. The results showed that the expression of CD147 and MCT1 was significantly reduced at both mRNA and protein levels, and also the activity of MMP-2 and MMP-9 was reduced. The proliferation and invasion were decreased, but chemosensitivity to cisplatin was increased. In vivo, the CD147 expression was also significantly decreased, and reduced the tumor growth after CD147 gene silencing. The results demonstrated that silencing of CD147 expression inhibited the proliferation and invasion, suggesting CD147 silencing might be an adjuvant gene therapy strategy to chemotherapy.

Chemosensitization as a Means to Augment Commercial Antifungal Agents

PubMed Central

Campbell, Bruce C.; Chan, Kathleen L.; Kim, Jong H.

2012-01-01

Antimycotic chemosensitization and its mode of action are of growing interest. Currently, use of antifungal agents in agriculture and medicine has a number of obstacles. Foremost of these is development of resistance or cross-resistance to one or more antifungal agents. The generally high expense and negative impact, or side effects, associated with antifungal agents are two further issues of concern. Collectively, these problems are exacerbated by efforts to control resistant strains, which can evolve into a treadmill of higher dosages for longer periods. This cycle in turn, inflates cost of treatment, dramatically. A further problem is stagnation in development of new and effective antifungal agents, especially for treatment of human mycoses. Efforts to overcome some of these issues have involved using combinations of available antimycotics (e.g., combination therapy for invasive mycoses). However, this approach has had inconsistent success and is often associated with a marked increase in negative side effects. Chemosensitization by natural compounds to increase effectiveness of commercial antimycotics is a somewhat new approach to dealing with the aforementioned problems. The potential for safe natural products to improve antifungal activity has been observed for over three decades. Chemosensitizing agents possess antifungal activity, but at insufficient levels to serve as antimycotics, alone. Their main function is to disrupt fungal stress response, destabilize the structural integrity of cellular and vacuolar membranes or stimulate production of reactive oxygen species, augmenting oxidative stress and apoptosis. Use of safe chemosensitizing agents has potential benefit to both agriculture and medicine. When co-applied with a commercial antifungal agent, an additive or synergistic interaction may occur, augmenting antifungal efficacy. This augmentation, in turn, lowers effective dosages, costs, negative side effects and, in some cases, countermands resistance. PMID:22393330

P53 Is Involved in a Three-Dimensional Architecture-Mediated Decrease in Chemosensitivity in Colon Cancer.

PubMed

He, Jianming; Liang, Xi; Luo, Fen; Chen, Xuedan; Xu, Xueqing; Wang, Fengchao; Zhang, Zhenping

2016-01-01

Three-dimensional (3D) culture models represent a better approximation of solid tumor tissue architecture, especially cell adhesion, in vivo than two-dimensional (2D) cultures do. Here, we explored the role of architecture in chemosensitivity to platinum in colon cancer. Under the 3D culture condition, colon cancer cells formed multicellular spheroids, consisting of layers of cells. 3D cultures displayed significantly decreased sensitivity to platinum compared with 2D cultures. Platinum increased p53 in a dose-dependent and time-dependent manner. There was no detectable difference in basal p53 levels between 3D cultures and 2D cultures but cisplatin induced less p53 in both HCT116 3D cultures and LoVo 3D cultures. It was not due to cisplatin concentration because cisplatin induced similar γ-H2AX in 3D vs 2D. Knockdown of p53 significantly decreased sensitivity to platinum in 3D cultures. Knockdown of p53 decreased cleaved caspase 3 and apoptosis induced by cisplatin. These findings indicate that 3D architecture confers decreased chemosensitivity to platinum and p53 is involved in the mechanism. Knockdown of p53 decreased cisplatin's induction of c-Jun N-terminal kinase 1/2 (JNK1/2) activation, whereas inhibition of JNK1/2 activation increased chemosensitivity. Inhibition of p38 activation decreased cisplatin's induction of p53, but no difference in p38 activation by cisplatin was observed between 2D cultures and 3D cultures. Taken together, our results suggest that p53 is involved in a 3D architecture-mediated decrease in chemosensitivity to platinum in colon cancer. Mitogen-activated protein kinases (JNK1/2 and p38) do not play a dominant role in the mechanism.

Intermittent hypercapnia induces long-lasting ventilatory plasticity to enhance CO2 responsiveness to overcome dysfunction

NASA Astrophysics Data System (ADS)

Mosher, Bryan Patrick

The ability of the brain to detect (central CO2 chemosensitivity) and respond to (central CO2 chemoresponsiveness) changes in tissue CO2/pH, is a homeostatic process essential for mammalian life. Dysfunction of the serotonin (5-HT) mechanisms compromises ventilatory CO 2 chemosensitivity/responsiveness and may enhance vulnerability to pathologies such as the Sudden Infant Death Syndrome (SIDS). The laboratory of Dr. Michael Harris has shown medullary raphe contributions to central chemosensitivity involving both 5-HT- and gamma-aminobutyric acid (GABA)-mediated mechanisms. I tested the hypothesis that postnatal exposure to mild intermittent hypercapnia (IHc) induces respiratory plasticity, due in part to strengthening of bicuculline- and saclofen-sensitive mechanisms (GABAA and GABAB receptor antagonists respectively). Rats were exposed to IHc-pretreatment (8 cycles of 5 % CO2) for 5 days beginning at postnatal day 12 (P12). I subsequently assessed CO2 responsiveness using an in situ perfused brainstem preparation. Hypercapnic responses were determined with and without pharmacological manipulation. In addition, IHc-pretreatment effectiveness was tested for its ability to overcome dysfunction in the CO2 responsiveness induced by a dietary tryptophan restriction. This dysfunctional CO2 responsiveness has been suggested to arise from a chronic, partial 5-HT reduction imparted by the dietary restriction. Results show IHc-pretreatment induced plasticity sufficient for CO2 responsiveness despite removal of otherwise critical ketanserin-sensitive mechanisms. CO2 responsiveness following IHc-pretreatment was absent if ketanserin was combined with bicuculline and saclofen, indicating that the plasticity was dependent upon bicuculline- and saclofen-sensitive mechanisms. IHc--induced plasticity was also capable of overcoming the ventilatory defects associated with maternal dietary restriction. Duration of IHc-induced plasticity was also investigated and found to last far into life (up to P65). Furthermore, I performed experiments to investigate if IHc-induced plasticity was more robust at a specific developmental period. No such critical period was identified as IHc-pretreatment induced robust respiratory plasticity when administered at all developmental periods tested (P12-16, P21-25 and P36-0). I propose that IHc-induced plasticity may be able to reduce the severity of reflex dysfunctions underlying pathologies such as SIDS.

Genomic evolution and chemoresistance in germ-cell tumours.

PubMed

Taylor-Weiner, Amaro; Zack, Travis; O'Donnell, Elizabeth; Guerriero, Jennifer L; Bernard, Brandon; Reddy, Anita; Han, G Celine; AlDubayan, Saud; Amin-Mansour, Ali; Schumacher, Steven E; Litchfield, Kevin; Turnbull, Clare; Gabriel, Stacey; Beroukhim, Rameen; Getz, Gad; Carter, Scott L; Hirsch, Michelle S; Letai, Anthony; Sweeney, Christopher; Van Allen, Eliezer M

2016-11-30

Germ-cell tumours (GCTs) are derived from germ cells and occur most frequently in the testes. GCTs are histologically heterogeneous and distinctly curable with chemotherapy. Gains of chromosome arm 12p and aneuploidy are nearly universal in GCTs, but specific somatic genomic features driving tumour initiation, chemosensitivity and progression are incompletely characterized. Here, using clinical whole-exome and transcriptome sequencing of precursor, primary (testicular and mediastinal) and chemoresistant metastatic human GCTs, we show that the primary somatic feature of GCTs is highly recurrent chromosome arm level amplifications and reciprocal deletions (reciprocal loss of heterozygosity), variations that are significantly enriched in GCTs compared to 19 other cancer types. These tumours also acquire KRAS mutations during the development from precursor to primary disease, and primary testicular GCTs (TGCTs) are uniformly wild type for TP53. In addition, by functional measurement of apoptotic signalling (BH3 profiling) of fresh tumour and adjacent tissue, we find that primary TGCTs have high mitochondrial priming that facilitates chemotherapy-induced apoptosis. Finally, by phylogenetic analysis of serial TGCTs that emerge with chemotherapy resistance, we show how TGCTs gain additional reciprocal loss of heterozygosity and that this is associated with loss of pluripotency markers (NANOG and POU5F1) in chemoresistant teratomas or transformed carcinomas. Our results demonstrate the distinct genomic features underlying the origins of this disease and associated with the chemosensitivity phenotype, as well as the rare progression to chemoresistance. These results identify the convergence of cancer genomics, mitochondrial priming and GCT evolution, and may provide insights into chemosensitivity and resistance in other cancers.

Central respiratory chemosensitivity and cerebrovascular CO2 reactivity: a rebreathing demonstration illustrating integrative human physiology.

PubMed

MacKay, Christina M; Skow, Rachel J; Tymko, Michael M; Boulet, Lindsey M; Davenport, Margie H; Steinback, Craig D; Ainslie, Philip N; Lemieux, Chantelle C M; Day, Trevor A

2016-03-01

One of the most effective ways of engaging students of physiology and medicine is through laboratory demonstrations and case studies that combine 1) the use of equipment, 2) problem solving, 3) visual representations, and 4) manipulation and interpretation of data. Depending on the measurements made and the type of test, laboratory demonstrations have the added benefit of being able to show multiple organ system integration. Many research techniques can also serve as effective demonstrations of integrative human physiology. The "Duffin" hyperoxic rebreathing test is often used in research settings as a test of central respiratory chemosensitivity and cerebrovascular reactivity to CO2. We aimed to demonstrate the utility of the hyperoxic rebreathing test for both respiratory and cerebrovascular responses to increases in CO2 and illustrate the integration of the respiratory and cerebrovascular systems. In the present article, methods such as spirometry, respiratory gas analysis, and transcranial Doppler ultrasound are described, and raw data traces can be adopted for discussion in a tutorial setting. If educators have these instruments available, instructions on how to carry out the test are provided so students can collect their own data. In either case, data analysis and quantification are discussed, including principles of linear regression, calculation of slope, the coefficient of determination (R(2)), and differences between plotting absolute versus normalized data. Using the hyperoxic rebreathing test as a demonstration of the complex interaction and integration between the respiratory and cerebrovascular systems provides senior undergraduate, graduate, and medical students with an advanced understanding of the integrative nature of human physiology. Copyright © 2016 The American Physiological Society.

Dual Agent Loaded PLGA Nanoparticles Enhanced Antitumor Activity in a Multidrug-Resistant Breast Tumor Eenograft Model

PubMed Central

Chen, Yan; Zheng, Xue-Lian; Fang, Dai-Long; Yang, Yang; Zhang, Jin-Kun; Li, Hui-Li; Xu, Bei; Lei, Yi; Ren, Ke; Song, Xiang-Rong

2014-01-01

Multidrug-resistant breast cancers have limited and ineffective clinical treatment options. This study aimed to develop PLGA nanoparticles containing a synergistic combination of vincristine and verapamil to achieve less toxicity and enhanced efficacy on multidrug-resistant breast cancers. The 1:250 molar ratio of VCR/VRP showed strong synergism with the reversal index of approximately 130 in the multidrug-resistant MCF-7/ADR cells compared to drug-sensitive MCF-7 cells. The lyophilized nanoparticles could get dispersed quickly with the similar size distribution, zeta potential and encapsulation efficiency to the pre-lyophilized nanoparticles suspension, and maintain the synergistic in vitro release ratio of drugs. The co-encapsulated nanoparticle formulation had lower toxicity than free vincristine/verapamil combinations according to the acute-toxicity test. Furthermore, the most effective tumor growth inhibition in the MCF-7/ADR human breast tumor xenograft was observed in the co-delivery nanoparticle formulation group in comparison with saline control, free vincristine, free vincristine/verapamil combinations and single-drug nanoparticle combinations. All the data demonstrated that PLGANPs simultaneously loaded with chemotherapeutic drug and chemosensitizer might be one of the most potential formulations in the treatment of multidrug-resistant breast cancer in clinic. PMID:24552875

Development and molecular characterization of polymeric micro-nanofibrous scaffold of a defined 3-D niche for in vitro chemosensitivity analysis against acute myeloid leukemia cells

PubMed Central

Nair, Maya S; Mony, Ullas; Menon, Deepthy; Koyakutty, Manzoor; Sidharthan, Neeraj; Pavithran, Keechilat; Nair, Shantikumar V; Menon, Krishnakumar N

2015-01-01

Standard in vitro drug testing employs 2-D tissue culture plate systems to test anti-leukemic drugs against cell adhesion-mediated drug-resistant leukemic cells that harbor in 3-D bone marrow microenvironments. This drawback necessitates the fabrication of 3-D scaffolds that have cell adhesion-mediated drug-resistant properties similar to in vivo niches. We therefore aimed at exploiting the known property of polyurethane (PU)/poly-l-lactic acid (PLLA) in forming a micro-nanofibrous structure to fabricate unique, not presented before, as far as we are aware, 3-D micro-nanofibrous scaffold composites using a thermally induced phase separation technique. Among the different combinations of PU/PLLA composites generated, the unique PU/PLLA 60:40 composite displayed micro-nanofibrous morphology similar to decellularized bone marrow with increased protein and fibronectin adsorption. Culturing of acute myeloid leukemia (AML) KG1a cells in FN-coated PU/PLLA 60:40 shows increased cell adhesion and cell adhesion-mediated drug resistance to the drugs cytarabine and daunorubicin without changing the original CD34+/CD38−/CD33− phenotype for 168 hours compared to fibronectin tissue culture plate systems. Molecularly, as seen in vivo, increased chemoresistance is associated with the upregulation of anti-apoptotic Bcl2 and the cell cycle regulatory protein p27Kip1 leading to cell growth arrest. Abrogation of Bcl2 activity by the Bcl2-specific inhibitor ABT 737 led to cell death in the presence of both cytarabine and daunorubicin, demonstrating that the cell adhesion-mediated drug resistance induced by Bcl2 and p27Kip1 in the scaffold was similar to that seen in vivo. These results thus show the utility of a platform technology, wherein drug testing can be performed before administering to patients without the necessity for stromal cells. PMID:26028971

Nasal solitary chemoreceptor cell responses to bitter and trigeminal stimulants in vitro.

PubMed

Gulbransen, Brian D; Clapp, Tod R; Finger, Thomas E; Kinnamon, Sue C

2008-06-01

Nasal trigeminal chemosensitivity in mice and rats is mediated in part by epithelial solitary chemoreceptor (chemosensory) cells (SCCs), but the exact role of these cells in chemoreception is unclear. Histological evidence suggests that SCCs express elements of the bitter taste transduction pathway including T2R (bitter taste) receptors, the G protein alpha-gustducin, PLCbeta2, and TRPM5, leading to speculation that SCCs are the receptor cells that mediate trigeminal nerve responses to bitter taste receptor ligands. To test this hypothesis, we used calcium imaging to determine whether SCCs respond to classic bitter-tasting or trigeminal stimulants. SCCs from the anterior nasal cavity were isolated from transgenic mice in which green fluorescent protein (GFP) expression was driven by either TRPM5 or gustducin. Isolated cells were exposed to a variety of test stimuli to determine which substances caused an increase in intracellular Ca2+ ([Ca2+]i). GFP-positive cells respond with increased [Ca2+]i to the bitter receptor ligand denatonium and this response is blocked by the PLC inhibitor U73122. In addition, GFP+ cells respond to the neuromodulators adenosine 5'-triphosphate and acetylcholine but only very rarely to other bitter-tasting or trigeminal stimuli. Our results demonstrate that TRPM5- and gustducin-expressing nasal SCCs respond to the T2R agonist denatonium via a PLC-coupled transduction cascade typical of T2Rs in the taste system.

Droplet-based microtumor model to assess cell-ECM interactions and drug resistance of gastric cancer cells.

PubMed

Jang, Minjeong; Koh, Ilkyoo; Lee, Seok Jae; Cheong, Jae-Ho; Kim, Pilnam

2017-01-27

Gastric cancer (GC) is a common aggressive malignant tumor with high incidence and mortality worldwide. GC is classified into intestinal and diffuse types according to the histo-morphological features. Because of distinctly different clinico-pathological features, new cancer therapy strategies and in vitro preclinical models for the two pathological variants of GC is necessary. Since extracellular matrix (ECM) influence the biological behavior of tumor cells, we hypothesized that GC might be more similarly modeled in 3D with matrix rather than in 2D. Herein, we developed a microfluidic-based a three-dimensional (3D) in vitro gastric cancer model, with subsequent drug resistance assay. AGS (intestinal type) and Hs746T (diffuse type) gastric cancer cell lines were encapsulated in collagen beads with high cellular viability. AGS exhibited an aggregation pattern with expansive growth, whereas Hs746T showed single-cell-level infiltration. Importantly, in microtumor models, epithelial-mesenchymal transition (EMT) and metastatic genes were upregulated, whereas E-cadherin was downregulated. Expression of ß-catenin was decreased in drug-resistant cells, and chemosensitivity toward the anticancer drug (5-FU) was observed in microtumors. These results suggest that in vitro microtumor models may represent a biologically relevant platform for studying gastric cancer cell biology and tumorigenesis, and for accelerating the development of novel therapeutic targets.

Dioscin enhances methotrexate absorption by down-regulating MDR1 in vitro and in vivo

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

Wang, Lijuan, E-mail: jlwang1979@163.com; Wang, Changyuan, E-mail: wangcyuan@163.com; Provincial Key Laboratory for Pharmacokinetics and Transport, Liaoning, Dalian Medical University, Dalian, Liaoning

2014-06-01

The purpose of this study was to investigate the enhancing effect of dioscin on the absorption of methotrexate (MTX) and clarify the molecular mechanism involved in vivo and in vitro. Dioscin increased MTX chemosensitivity and transepithelial flux in the absorptive direction, significantly inhibiting multidrug resistance 1 (MDR1) mRNA and protein expression and MDR1 promoter and nuclear factor κ-B (NF-κB) activities in Caco-2 cells. Moreover, inhibitor κB-α (IκB-α) degradation was inhibited by dioscin. Dioscin enhanced the intracellular concentration of MTX by down-regulating MDR1 expression through a mechanism that involves NF-κB signaling pathway inhibition in Caco-2 cells. Dioscin strengthened MTX absorption bymore » inhibiting MDR1 expression in rat intestine. In addition, even though MTX is absorbed into the enterocytes, there was no increase in toxicity observed, and that, in fact, decreased toxicity was seen. - Highlights: • Dioscin raised MTX concentration by inhibiting MDR1 in Caco-2 cells. • Dioscin suppresses MDR1 by inhibiting NF-κB signaling pathway in Caco-2 cells. • Dioscin can enhance MTX absorption via inhibiting MDR1 in vivo and in vitro. • Dioscin did not increase MTX-induced gastrointestinal mucosal toxicity.« less

Knockdown of cullin 4A inhibits growth and increases chemosensitivity in lung cancer cells.

PubMed

Hung, Ming-Szu; Chen, I-Chuan; You, Liang; Jablons, David M; Li, Ya-Chin; Mao, Jian-Hua; Xu, Zhidong; Lung, Jr-Hau; Yang, Cheng-Ta; Liu, Shih-Tung

2016-07-01

Cullin 4A (Cul4A) has been observed to be overexpressed in various cancers. In this study, the role of Cul4A in the growth and chemosensitivity in lung cancer cells were studied. We showed that Cul4A is overexpressed in lung cancer cells and tissues. Knockdown of the Cul4A expression by shRNA in lung cancer cells resulted in decreased cellular proliferation and growth in lung cancer cells. Increased sensitivity to gemcitabine, a chemotherapy drug, was also noted in those Cul4A knockdown lung cancer cells. Moreover, increased expression of p21, transforming growth factor (TGF)-β inducible early gene-1 (TIEG1) and TGF beta-induced (TGFBI) was observed in lung cancer cells after Cul4A knockdown, which may be partially related to increased chemosensitivity to gemcitabine. G0/G1 cell cycle arrest was also noted after Cul4A knockdown. Notably, decreased tumour growth and increased chemosensitivity to gemcitabine were also noted after Cul4A knockdown in lung cancer xenograft nude mice models. In summary, our study showed that targeting Cul4A with RNAi or other techniques may provide a possible insight to the development of lung cancer therapy in the future. © 2016 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

MicroRNA-137 inhibits tumor growth and sensitizes chemosensitivity to paclitaxel and cisplatin in lung cancer

PubMed Central

Ge, Xin; Jiang, Cheng-Fei; Shi, Zhu-Mei; Li, Dong-Mei; Liu, Wei-Tao; Yu, Xiaobo; Shu, Yong-Qian

2016-01-01

Chemotherapy resistance frequently drives tumour progression. However, the underlying molecular mechanisms are poorly characterized. In this study, we explored miR-137's role in the chemosensitivity of lung cancer. We found that the expression level of miR-137 is down-regulated in the human lung cancer tissues and the resistant cells strains: A549/paclitaxel(A549/PTX) and A549/cisplatin (A549/CDDP) when compared with lung cancer A549 cells. Moreover, we found that overe-expression of miR-137 inhibited cell proliferation, migration, cell survival and arrest the cell cycle in G1 phase in A549/PTX and A549/CDDP. Furthermore, Repression of miR-137 significantly promoted cell growth, migration, cell survival and cell cycle G1/S transition in A549 cells. We further demonstrated that the tumor suppressive role of miR-137 was mediated by negatively regulating Nuclear casein kinase and cyclin-dependent kinase substrate1(NUCKS1) protein expression. Importantly, miR-137 inhibits A549/PTX, A549/CDDP growth and angiogenesis in vivo. Our study is the first to identify the tumor suppressive role of over-expressed miR-137 in chemosensitivity. Identification of a novel miRNA-mediated pathway that regulates chemosensitivity in lung cancer will facilitate the development of novel therapeutic strategies in the future. PMID:26989074

A series of structurally simple chloroquine chemosensitizing dibemethin derivatives that inhibit chloroquine transport by PfCRT.

PubMed

Zishiri, Vincent K; Hunter, Roger; Smith, Peter J; Taylor, Dale; Summers, Robert; Kirk, Kiaran; Martin, Rowena E; Egan, Timothy J

2011-05-01

A series of 12 new dibemethin (N-benzyl-N-methyl-1-phenylmethanamine) derivatives bearing an N-aminomethyl group attached to the one phenyl ring and an H, Cl, OCH3 or N(CH3)2 group on the other have been synthesized. These compounds all showed strong chloroquine chemosensitizing activity, comparable to verapamil, when present at 1 μM in an in vitro culture of the chloroquine-resistant W2 strain of the human malaria parasite, Plasmodium falciparum. Their N-formylated derivatives also exhibited resistance-reversing activity, but only at substantially higher IC10 concentrations. A number of the dibemethin derivatives were shown to inhibit chloroquine transport via the parasite's 'chloroquine resistance transporter' (PfCRT) in a Xenopus laevis oocyte expression system. The reduced resistance-reversing activity of the formylated compounds relative to their free amine counterparts can probably be ascribed to two factors: decreased accumulation of the formylated dibemethins within the parasite's internal digestive vacuole (believed to be the site of action of chloroquine), and a reduced ability to inhibit PfCRT. The resistance-reversing activity of the compounds described here demonstrates that the amino group need not be attached to the two aromatic rings via a three or four carbon chain as has been suggested by previous QSAR studies. These compounds may be useful as potential side chains for attaching to a 4,7-dichloroquinoline group in order to generate new resistance-reversing chloroquine analogues with inherent antimalarial activity. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

Design, synthesis, anti-lung cancer activity, and chemosensitization of tumor-selective MCACs based on ROS-mediated JNK pathway activation and NF-κB pathway inhibition.

PubMed

Chen, Liping; Li, Qian; Weng, Bixia; Wang, Jiabing; Zhou, Yangyang; Cheng, Dezhi; Sirirak, Thanchanok; Qiu, Peihong; Wu, Jianzhang

2018-05-10

EF24 and F35 both were effective monocarbonyl curcumin analogues (MCACs) with excellent anti-tumor activity, however, drug defect such as toxicity may limit their further development. To get anti-lung cancer drugs with high efficiency, low toxicity and chemosensitization, a series of analogues based on EF24 and F35 were designed and synthesized. A number of compounds were found to exhibit cytotoxic activities selectively towards lung cancer cells compared to normal cells. Among these compounds, 5B was considered as an optimal anti-tumor agent for lung cancer cells with IC 50 values ranging from 1.0 to 1.7 μM, selectivity index (SI, as a logarithm of a ratio of IC 50 value for normal and cancer cells) were all above 1.1, while the SI of EF24 and F35 were less than 0.8. Consistent with selectivity in vitro, 5B was observed to show lower toxicity in acute toxicity experiment than EF24 and F35 respectively. Further, 5B was found to exert anti-tumor effects through ROS-mediated activation of JNK pathway and inhibition of NF-κB pathway. 5B could significantly enhance the sensitivity of A549 cells to cisplatin or 5-Fu. These findings suggested that 5B was an effective and less toxic MCAC and provided a promising candidate for anti-tumor drugs. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

Curcumin-induced Aurora-A suppression not only causes mitotic defect and cell cycle arrest but also alters chemosensitivity to anticancer drugs.

PubMed

Ke, Ching-Shiun; Liu, Hsiao-Sheng; Yen, Cheng-Hsin; Huang, Guan-Cheng; Cheng, Hung-Chi; Huang, Chi-Ying F; Su, Chun-Li

2014-05-01

Overexpression of oncoprotein Aurora-A increases drug resistance and promotes lung metastasis of breast cancer cells. Curcumin is an active anticancer compound in turmeric and curry. Here we observed that Aurora-A protein and kinase activity were reduced in curcumin-treated human breast chemoresistant nonmetastatic MCF-7 and highly metastatic cancer MDA-MB-231 cells. Curcumin acts in a similar manner to Aurora-A small interfering RNA (siRNA), resulting in monopolar spindle formation, S and G2/M arrest, and cell division reduction. Ectopic Aurora-A extinguished the curcumin effects. The anticancer effects of curcumin were enhanced by Aurora-A siRNA and produced additivity and synergism effects in cell division and monopolar phenotype, respectively. Combination treatment with curcumin overrode the chemoresistance to four Food and Drug Administration (FDA)-approved anticancer drugs (ixabepilone, cisplatin, vinorelbine, or everolimus) in MDA-MB-231 cells, which was characterized by a decrease in cell viability and the occurrence of an additivity or synergy effect. Ectopic expression of Aurora-A attenuated curcumin-enhanced chemosensitivity to these four tested drugs. A similar benefit of curcumin was observed in MCF-7 cells treated with ixabepilone, the primary systemic therapy to patients with invasive breast cancer (stages IIA-IIIB) before surgery. Antagonism effect was observed when MCF-7 cells were treated with curcumin plus cisplatin, vinorelbine or everolimus. Curcumin-induced enhancement in chemosensitivity was paralleled by significant increases (additivity or synergy effect) in apoptosis and cell cycle arrest at S and G2/M phases, the consequences of Aurora-A inhibition. These results suggest that a combination of curcumin with FDA-approved anticancer drugs warrants further assessment with a view to developing a novel clinical treatment for breast cancer. Copyright © 2014 Elsevier Inc. All rights reserved.

Low hypoxia inducible factor-1α (HIF-1α) expression in testicular germ cell tumors - a major reason for enhanced chemosensitivity?

PubMed

Shenoy, Niraj; Dronca, Roxana; Quevedo, Fernando; Boorjian, Stephen A; Cheville, John; Costello, Brian; Kohli, Manish; Witzig, Thomas; Pagliaro, Lance

2017-08-01

The molecular basis for enhanced chemosensitivity of testicular germ cell tumors (GCT) has been an area of great interest, as it could potentially give us therapeutic leads in other resistant malignancies. Thus far, however, the increased sensitivity of GCT has been variously attributed to multiple factors - an inability to detoxify cisplatin, a lack of export pumps, an inability to repair the DNA damage, an intact apoptotic cascade and lack of p53 mutation; but a unifying underlying etiology leading to the aforementioned processes and having a translational implication has so far been elusive. Herein, we offer evidence to support a potential significant role for the previously demonstrated low hypoxia inducible factor-1α (HIF-1α) expression in mediating the general exquisite chemosensitivity of testicular GCT, through the aforementioned processes. This molecular mechanism based hypothesis could have a significant translational implication in platinum refractory GCT as well as other platinum resistant malignancies.

ω-3 Long Chain Polyunsaturated Fatty Acids as Sensitizing Agents and Multidrug Resistance Revertants in Cancer Therapy

PubMed Central

Corsetto, Paola Antonia; Kopecka, Joanna; Riganti, Chiara

2017-01-01

Chemotherapy efficacy is strictly limited by the resistance of cancer cells. The ω-3 long chain polyunsaturated fatty acids (ω-3 LCPUFAs) are considered chemosensitizing agents and revertants of multidrug resistance by pleiotropic, but not still well elucidated, mechanisms. Nowadays, it is accepted that alteration in gene expression, modulation of cellular proliferation and differentiation, induction of apoptosis, generation of reactive oxygen species, and lipid peroxidation are involved in ω-3 LCPUFA chemosensitizing effects. A crucial mechanism in the control of cell drug uptake and efflux is related to ω-3 LCPUFA influence on membrane lipid composition. The incorporation of docosahexaenoic acid in the lipid rafts produces significant changes in their physical-chemical properties affecting content and functions of transmembrane proteins, such as growth factors, receptors and ATP-binding cassette transporters. Of note, ω-3 LCPUFAs often alter the lipid compositions more in chemoresistant cells than in chemosensitive cells, suggesting a potential adjuvant role in the treatment of drug resistant cancers. PMID:29261109

20(S)-Protopanaxadiol (PPD) analogues chemosensitize multidrug-resistant cancer cells to clinical anticancer drugs.

PubMed

Liu, Junhua; Wang, Xu; Liu, Peng; Deng, Rongxin; Lei, Min; Chen, Wantao; Hu, Lihong

2013-07-15

Novel 20(S)-protopanoxadiol (PPD) analogues were designed, synthesized, and evaluated for the chemosensitizing activity against a multidrug resistant (MDR) cell line (KBvcr) overexpressing P-glycoprotein (P-gp). Structure-activity relationship analysis showed that aromatic substituted aliphatic amine at the 24-positions (groups V) effectively and significantly sensitized P-gp overexpressing multidrug resistant (MDR) cells to anticancer drugs, such as docetaxel (DOC), vincristine (VCR), and adriamycin (ADM). PPD derivatives 12 and 18 showed 1.3-2.6 times more effective reversal ability than verapamil (VER) for DOC and VCR. Importantly, no cytotoxicity was observed by the active PPD analogues (5μM) against both non-MDR and MDR cells, suggesting that PPD analogues serve as novel lead compounds toward a potent and safe resistance modulator. Moreover, a preliminary mechanism study demonstrated that the chemosensitizing activity of PPD analogues results from inhibition of P-glycoprotein (P-gp) overexpressed in MDR cancer cells. Copyright © 2013 The Authors. Published by Elsevier Ltd.. All rights reserved.

Glutathione S-transferase P1 (GSTP1) directly influences platinum drug chemosensitivity in ovarian tumour cell lines.

PubMed

Sawers, L; Ferguson, M J; Ihrig, B R; Young, H C; Chakravarty, P; Wolf, C R; Smith, G

2014-09-09

Chemotherapy response in ovarian cancer patients is frequently compromised by drug resistance, possibly due to altered drug metabolism. Platinum drugs are metabolised by glutathione S-transferase P1 (GSTP1), which is abundantly, but variably expressed in ovarian tumours. We have created novel ovarian tumour cell line models to investigate the extent to which differential GSTP1 expression influences chemosensitivity. Glutathione S-transferase P1 was stably deleted in A2780 and expression significantly reduced in cisplatin-resistant A2780DPP cells using Mission shRNA constructs, and MTT assays used to compare chemosensitivity to chemotherapy drugs used to treat ovarian cancer. Differentially expressed genes in GSTP1 knockdown cells were identified by Illumina HT-12 expression arrays and qRT-PCR analysis, and altered pathways predicted by MetaCore (GeneGo) analysis. Cell cycle changes were assessed by FACS analysis of PI-labelled cells and invasion and migration compared in quantitative Boyden chamber-based assays. Glutathione S-transferase P1 knockdown selectively influenced cisplatin and carboplatin chemosensitivity (2.3- and 4.83-fold change in IC50, respectively). Cell cycle progression was unaffected, but cell invasion and migration was significantly reduced. We identified several novel GSTP1 target genes and candidate platinum chemotherapy response biomarkers. Glutathione S-transferase P1 has an important role in cisplatin and carboplatin metabolism in ovarian cancer cells. Inter-tumour differences in GSTP1 expression may therefore influence response to platinum-based chemotherapy in ovarian cancer patients.

Stabilization of mismatch repair gene PMS2 by glycogen synthase kinase 3β is implicated in the treatment of cervical carcinoma

PubMed Central

2010-01-01

Background PMS2 expression loss was reported in a variety of human. However, its importance has not been fully understood in cervical carcinoma. The aim of this study was to determine the expression of PMS2 in cervical carcinoma and evaluate the significance of mismatch repair gene PMS2 regulated by glycogen synthase kinase 3β (GSK-3β) in chemosensitivity. Methods We examined PMS2 and phosphorylated GSK-3β(s9) expression in cervical carcinoma tissues using immunohistochemical staining. Furthermore, we detected PMS2 expression in HeLa cells and evaluate the interaction with GSK-3β after transfection with GSK-3β by small interference RNA (siRNA), co-immunoprecipitation and immunoblotting. We also evaluated the effect of PMS2 transfection on HeLa cells' chemosensitivity to cisplatin treatment. Results We found significant downregulation of PMS2 in cervical carcinoma, which was negatively associated with phosphorylated GSK-3β (s9). Furthermore, we demonstrated GSK-3β transfection was able to interact with PMS2 and enhance PMS2 production in HeLa cells, and increased PMS2 production was responsible for enhanced chemosensitivity. Conclusions Our results provide the evidence that stabilization of PMS2 production by GSK-3β was important to improve chemosensitization, indicating the significance of GSK-3β-related PMS2 downregulation in the development of cervical carcinoma and in developing a potential strategy for chemotherapy. PMID:20178594

Stabilization of mismatch repair gene PMS2 by glycogen synthase kinase 3beta is implicated in the treatment of cervical carcinoma.

PubMed

Zhang, Yuan; Shu, Yi Min; Wang, Shu Fang; Da, Bang Hong; Wang, Ze Hua; Li, Hua Bin

2010-02-23

PMS2 expression loss was reported in a variety of human. However, its importance has not been fully understood in cervical carcinoma. The aim of this study was to determine the expression of PMS2 in cervical carcinoma and evaluate the significance of mismatch repair gene PMS2 regulated by glycogen synthase kinase 3beta (GSK-3beta) in chemosensitivity. We examined PMS2 and phosphorylated GSK-3beta(s9) expression in cervical carcinoma tissues using immunohistochemical staining. Furthermore, we detected PMS2 expression in HeLa cells and evaluate the interaction with GSK-3beta after transfection with GSK-3beta by small interference RNA (siRNA), co-immunoprecipitation and immunoblotting. We also evaluated the effect of PMS2 transfection on HeLa cells' chemosensitivity to cisplatin treatment. We found significant downregulation of PMS2 in cervical carcinoma, which was negatively associated with phosphorylated GSK-3beta (s9). Furthermore, we demonstrated GSK-3beta transfection was able to interact with PMS2 and enhance PMS2 production in HeLa cells, and increased PMS2 production was responsible for enhanced chemosensitivity. Our results provide the evidence that stabilization of PMS2 production by GSK-3beta was important to improve chemosensitization, indicating the significance of GSK-3beta-related PMS2 downregulation in the development of cervical carcinoma and in developing a potential strategy for chemotherapy.

Horizontal transfer of miR-106a/b from cisplatin resistant hepatocarcinoma cells can alter the sensitivity of cervical cancer cells to cisplatin.

PubMed

Raji, Grace R; Sruthi, T V; Edatt, Lincy; Haritha, K; Sharath Shankar, S; Sameer Kumar, V B

2017-10-01

Recent studies indicate that horizontal transfer of genetic material can act as a communication tool between heterogenous populations of tumour cells, thus altering the chemosensitivity of tumour cells. The present study was designed to check whether the horizontal transfer of miRNAs released by cisplatin resistant (Cp-r) Hepatocarcinoma cells can alter the sensitivity of cervical cancer cells. For this exosomes secreted by cisplatin resistant and cisplatin sensitive HepG2 cells (EXres and EXsen) were isolated and characterised. Cytotoxicity analysis showed that EXres can make Hela cells resistant to cisplatin. Analysis of miR-106a/b levels in EXres and EXsen showed that their levels vary. Mechanistic studies showed that miR-106a/b play an important role in EXsen and EXres mediated change in chemosensitivity of Hela cells to cisplatin. Further SIRT1 was identified as a major target of miR-106a/b using in silico tools and this was proved by experimentation. Also the effect of miR-106a/b in chemosensitivity was seen to be dependent on regulation of SIRT1 by miR-106a/b. In brief, this study brings into light, the SIRT1 dependent mechanism of miR-106a/b mediated regulation of chemosensitivity upon the horizontal transfer from one cell type to another. Copyright © 2017 Elsevier Inc. All rights reserved.

Theory of gastric CO2 ventilation and its control during respiratory acidosis: implications for central chemosensitivity, pH regulation, and diseases causing chronic CO2 retention.

PubMed

Dean, Jay B

2011-02-15

The theory of gastric CO(2) ventilation describes a previously unrecognized reflex mechanism controlled by neurons in the caudal solitary complex (cSC) for non-alveolar elimination of systemic CO(2) during respiratory acidosis. Neurons in the cSC, which is a site of CO(2) chemosensitivity for cardiorespiratory control, also control various gastroesophageal reflexes that remove CO(2) from blood. CO(2) is consumed in the production of gastric acid and bicarbonate in the gastric epithelium and then reconstituted as CO(2) in the stomach lumen from the reaction between H(+) and HCO(3)(-). Respiratory acidosis and gastric CO(2) distension induce cSC/vagovagal mediated transient relaxations of the lower esophageal sphincter to vent gastric CO(2) upwards by bulk flow along an abdominal-to-esophageal (=intrapleural) pressure gradient the magnitude of which increases during abdominal (gastric) compression caused by increased contractions of respiratory muscles. Esophageal distension induces cSC/nucleus ambiguus/vagovagal reflex relaxation of the upper esophageal sphincter and CO(2) is vented into the pharynx and mixed with pulmonary gas during expiration or, alternatively, during eructation. It is proposed that gastric CO(2) ventilation provides explanations for (1) the postprandial increase in expired CO(2) and (2) the negative P(blood - expired)CO₂difference that occurs with increased inspired CO(2). Furthermore, it is postulated that gastric CO(2) ventilation and alveolar CO(2) ventilation are coordinated under dual control by CO(2) chemosensitive neurons in the cSC. This new theory, therefore, presupposes a level of neural control and coordination between two previously presumed dissimilar organ systems and supports the notion that different sites of CO(2) chemosensitivity address different aspects of whole body pH regulation. Consequently, not all sites of central chemosensitivity are equal regarding the mechanism(s) activated for CO(2) elimination. A distributed CO(2) chemosensitive network-at least nine different areas in the CNS, including the cSC, have been reported to date-may reflect the complexity and dynamic nature of the fundamental neural circuitry required to achieve CO(2)/pH regulation across multiple organ systems under various states of arousal, oxygenation, pH status, and redox state. Moreover, coordination of respiratory and digestive control networks through the cSC could also account for the frequent co-expression of pulmonary diseases that cause chronic respiratory acidosis (and overstimulation of cSC neurons) with peptic ulcer disease or gastroesophageal reflux disease. Copyright © 2010 Elsevier B.V. All rights reserved.

The anti-tumor activity of E1A and its implications in cancer therapy.

PubMed

Chang, Yi-Wen; Hung, Mien-Chie; Su, Jen-Liang

2014-06-01

The adenovirus type 5 E1A protein (E1A) plays a critical role in anti-cancer gene therapy and has been tested in clinical trials. The expression of E1A significantly reduces tumorigenesis, promotes cell death, and inhibits cancer cell mobility. Chemosensitization is one of the anti-tumor effects of E1A, increasing in vitro and in vivo sensitization of anti-cancer drugs, including cisplatin, gemcitabine, etoposide, doxorubicin, paclitaxel, and tumor necrosis factor-related apoptosis-inducing ligand and histone deacetylase inhibitors in different types of cancer cells. E1A also demonstrates anti-metastasis activity through various molecular mechanisms such as the repression of protease expression, suppression of HER2/neu and downregulation of microRNA (miR-520h). Moreover, E1A has been reported to reprogram transcription in tumor cells and stabilize tumor suppressors such as PP2A/C, p21 and p53. Because E1A plays a potentially significant role in anti-tumor therapy, there exists an urgent need to study the anti-cancer activities of E1A. This paper presents a review of our current understanding of the tumor-suppressive functions and molecular regulation of E1A, as well as the potential clinical applications of E1A.

Antitumor activity and mechanism of action of the cyclopenta[b]benzofuran, silvestrol.

PubMed

Cencic, Regina; Carrier, Marilyn; Galicia-Vázquez, Gabriela; Bordeleau, Marie-Eve; Sukarieh, Rami; Bourdeau, Annie; Brem, Brigitte; Teodoro, Jose G; Greger, Harald; Tremblay, Michel L; Porco, John A; Pelletier, Jerry

2009-01-01

Flavaglines are a family of natural products from the genus Aglaia that exhibit anti-cancer activity in vitro and in vivo and inhibit translation initiation. They have been shown to modulate the activity of eIF4A, the DEAD-box RNA helicase subunit of the eukaryotic initiation factor (eIF) 4F complex, a complex that stimulates ribosome recruitment during translation initiation. One flavagline, silvestrol, is capable of modulating chemosensitivity in a mechanism-based mouse model. Among a number of flavagline family members tested herein, we find that silvestrol is the more potent translation inhibitor among these. We find that silvestrol impairs the ribosome recruitment step of translation initiation by affecting the composition of the eukaryotic initiation factor (eIF) 4F complex. We show that silvestrol exhibits significant anticancer activity in human breast and prostate cancer xenograft models, and that this is associated with increased apoptosis, decreased proliferation, and inhibition of angiogenesis. We demonstrate that targeting translation by silvestrol results in preferential inhibition of weakly initiating mRNAs. Our results indicate that silvestrol is a potent anti-cancer compound in vivo that exerts its activity by affecting survival pathways as well as angiogenesis. We propose that silvestrol mediates its effects by preferentially inhibiting translation of malignancy-related mRNAs. Silvestrol appears to be well tolerated in animals.

Decorin in human oral cancer: a promising predictive biomarker of S-1 neoadjuvant chemosensitivity.

PubMed

Kasamatsu, Atsushi; Uzawa, Katsuhiro; Minakawa, Yasuyuki; Ishige, Shunsaku; Kasama, Hiroki; Endo-Sakamoto, Yosuke; Ogawara, Katsunori; Shiiba, Masashi; Takiguchi, Yuichi; Tanzawa, Hideki

2015-01-30

We reported previously that decorin (DCN) is significantly up-regulated in chemoresistant cancer cell lines. DCN is a small leucine-rich proteoglycan that exists and functions in stromal and epithelial cells. Accumulating evidence suggests that DCN affects the biology of several types of cancer by directly/indirectly targeting the signaling molecules involved in cell growth, survival, metastasis, and angiogenesis, however, the molecular mechanisms of DCN in chemoresistance and its clinical relevance are still unknown. Here we assumed that DCN silencing cells increase chemosusceptibility to S-1, consisted of tegafur, prodrug of 5-fluorouracil. We first established DCN knockdown transfectants derived from oral cancer cells for following experiments including chemosusceptibility assay to S-1. In addition to the in vitro data, DCN knockdown zenografting tumors in nude mice demonstrate decreasing cell proliferation and increasing apoptosis with dephosphorylation of AKT after S-1 chemotherapy. We also investigated whether DCN expression predicts the clinical responses of neoadjuvant chemotherapy (NAC) using S-1 (S-1 NAC) for oral cancer patients. Immunohistochemistry data in the preoperative biopsy samples was analyzed to determine the cut-off point for status of DCN expression by receiver operating curve analysis. Interestingly, low DCN expression was observed in five (83%) of six cases with complete responses to S-1 NAC, and in one (10%) case of 10 cases with stable/progressive disease, indicating that S-1 chemosensitivity is dramatically effective in oral cancer patients with low DCN expression compared with high DCN expression. Our findings suggest that DCN is a key regulator for chemoresistant mechanisms, and is a predictive immunomarker of the response to S-1 NAC and patient prognosis. Copyright © 2014 Elsevier Inc. All rights reserved.

Patient-derived multicellular tumor spheroids towards optimized treatment for patients with hepatocellular carcinoma.

PubMed

Song, Yeonhwa; Kim, Jin-Sun; Kim, Se-Hyuk; Park, Yoon Kyung; Yu, Eunsil; Kim, Ki-Hun; Seo, Eul-Ju; Oh, Heung-Bum; Lee, Han Chu; Kim, Kang Mo; Seo, Haeng Ran

2018-05-25

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors worldwide and has poor prognosis. Specially, patients with HCC usually have poor tolerance of systemic chemotherapy, because HCCs develop from chronically damaged tissue that contains considerable inflammation, fibrosis, and cirrhosis. Since HCC exhibits highly heterogeneous molecular characteristics, a proper in vitro system is required for the study of HCC pathogenesis. To this end, we have established two new hepatitis B virus (HBV) DNA-secreting HCC cell lines from infected patients. Based on these two new HCC cell lines, we have developed chemosensitivity assays for patient-derived multicellular tumor spheroids (MCTSs) in order to select optimized anti-cancer drugs to provide more informative data for clinical drug application. To monitor the effect of the interaction of cancer cells and stromal cells in MCTS, we used a 3D co-culture model with patient-derived HCC cells and stromal cells from human hepatic stellate cells, human fibroblasts, and human umbilical vein endothelial cells to facilitate screening for optimized cancer therapy. To validate our system, we performed a comparison of chemosensitivity of the three culture systems, which are monolayer culture system, tumor spheroids, and MCTSs of patient-derived cells, to sorafenib, 5-fluorouracil, and cisplatin, as these compounds are typically standard therapy for advanced HCC in South Korea. In summary, these findings suggest that the MCTS culture system is the best methodology for screening for optimized treatment for each patients with HCC, because tumor spheroids not only mirror the 3D cellular context of the tumors but also exhibit therapeutically relevant pathophysiological gradients and heterogeneity of in vivo tumors.

In vitro anticancer evaluation of 5-fluorouracil lipid nanoparticles using B16F10 melanoma cell lines

NASA Astrophysics Data System (ADS)

Shenoy, Vikram S.; Gude, Rajiv P.; Murthy, Rayasa S. Ramachandra

2013-05-01

The present study is aimed to investigate the formulation and in vitro anticancer activities of solid lipid nanoparticles (SLNs) of 5-fluorouracil (5-FU) prepared using glyceryl monostearate (GMS) and cetyl palmitate (CP) by hot homogenization method. The lipids were selected based on the partition coefficient of 5-FU in lipids. The lipid nanoparticles were optimized for process and formulation parameters. The optimized nanoparticles were characterized for their zeta potential, morphology, release kinetics, and anticancer activity. Higher entrapments were achieved using a combination of emulsifiers. The zeta potential of the optimized CP and GMS SLN formulation were -8.26 and -9.35 mV, respectively. Both the optimized formulations were spherical. The in vitro release studies of SLNs of both the lipid carriers followed Peppas-Korsenmeyer equation when carried out at pH 3.5 and 7.4. The chemosensitivity assay carried out in B16F10 cell lines revealed that CP SLNs had better cytotoxicity than 5-FU solution and GMS SLNs at 48 h of incubation. Subtoxic concentration of 5-FU-loaded CP SLNs (0.12 μg/mL) possessed comparable antimigrational activity, colony inhibition activity, and cytopathic as that of 5-FU solution effects. The results indicated that encapsulating 5-FU in CP would be a promising delivery system for delivering 5-FU.

Nasal solitary chemoreceptor cell responses to bitter and trigeminal stimulants in vitro

PubMed Central

Gulbransen, Brian D; Clapp, Tod R; Kinnamon, Sue C; Finger, Thomas E

2009-01-01

Nasal trigeminal chemosensitivity in mice and rats is mediated in part by epithelial solitary chemoreceptor (chemosensory) cells (SCCs), but the exact role of these cells in chemoreception is unclear (Finger et al. 2003). Histological evidence suggests that SCCs express elements of the bitter taste transduction pathway including T2R (bitter taste) receptors, the G protein α-gustducin, PLCβ2, and TRPM5, leading to speculation that SCCs are the receptor cells that mediate trigeminal nerve responses to bitter taste receptor ligands. To test this hypothesis, we used calcium imaging to determine whether SCCs respond to classic bitter-tasting or trigeminal stimulants. SCCs from the anterior nasal cavity were isolated from transgenic mice in which green fluorescent protein (GFP) expression was driven by either TRPM5 or gustducin. Isolated cells were exposed to a variety of test stimuli to determine which substances caused an increase in intracellular Ca2+ ([Ca2+]i). GFP positive cells respond with increased [Ca2+]i to the bitter receptor ligand denatonium, and this response is blocked by the PLC inhibitor U73122. In addition GFP+ cells respond to the PLC activator 3M3FBS, the neuromodulators ATP and ACh, but only very rarely to other bitter-tasting or trigeminal stimuli. Our results demonstrate that TRPM5- and gustducin-expressing nasal SCCs respond to the T2R agonist, denatonium via a PLC-coupled transduction cascade typical of T2Rs in the taste system. PMID:18417634

Differential Processing of let-7a Precursors Influences RRM2 Expression and Chemosensitivity in Pancreatic Cancer: Role of LIN-28 and SET Oncoprotein

PubMed Central

Bhutia, Yangzom Doma; Hung, Sau Wai; Krentz, Madeline; Patel, Dimal; Lovin, Dylan; Manoharan, Radhika; Thomson, J. Michael; Govindarajan, Rajgopal

2013-01-01

Overexpression of ribonucleotide reductase subunit M2 (RRM2), involved in deoxyribonucleotide synthesis, drives the chemoresistance of pancreatic cancer to nucleoside analogs (e.g., gemcitabine). While silencing RRM2 by synthetic means has shown promise in reducing chemoresistance, targeting endogenous molecules, especially microRNAs (miRNAs), to advance chemotherapeutic outcomes has been poorly explored. Based on computational predictions, we hypothesized that the let-7 tumor suppressor miRNAs will inhibit RRM2-mediated gemcitabine chemoresistance in pancreatic cancer. Reduced expression of the majority of let-7 miRNAs with an inverse relationship to RRM2 expression was identified in innately gemcitabine-resistant pancreatic cancer cell lines. Direct binding of let-7 miRNAs to the 3′ UTR of RRM2 transcripts identified post-transcriptional regulation of RRM2 influencing gemcitabine chemosensitivity. Intriguingly, overexpression of human precursor-let-7 miRNAs led to differential RRM2 expression and chemosensitivity responses in a poorly differentiated pancreatic cancer cell line, MIA PaCa-2. Defective processing of let-7a precursors to mature forms, in part, explained the discrepancies observed with let-7a expressional outcomes. Consistently, the ratios of mature to precursor let-7a were progressively reduced in gemcitabine-sensitive L3.6pl and Capan-1 cell lines induced to acquire gemcitabine resistance. Besides known regulators of let-7 biogenesis (e.g., LIN-28), short hairpin RNA library screening identified several novel RNA binding proteins, including the SET oncoprotein, to differentially impact let-7 biogenesis and chemosensitivity in gemcitabine-sensitive versus -resistant pancreatic cancer cells. Further, LIN-28 and SET knockdown in the cells led to profound reductions in cellular proliferation and colony-formation capacities. Finally, defective processing of let-7a precursors with a positive correlation to RRM2 overexpression was identified in patient-derived pancreatic ductal adenocarcinoma (PDAC) tissues. These data demonstrate an intricate post-transcriptional regulation of RRM2 and chemosensitivity by let-7a and that the manipulation of regulatory proteins involved in let-7a transcription/processing may provide a mechanism for improving chemotherapeutic and/or tumor growth control responses in pancreatic cancer. PMID:23335963

Application of mitochondrial pyruvate carrier blocker UK5099 creates metabolic reprogram and greater stem-like properties in LnCap prostate cancer cells in vitro.

PubMed

Zhong, Yali; Li, Xiaoran; Yu, Dandan; Li, Xiaoli; Li, Yaqing; Long, Yuan; Yuan, Yuan; Ji, Zhenyu; Zhang, Mingzhi; Wen, Jian-Guo; Nesland, Jahn M; Suo, Zhenhe

2015-11-10

Aerobic glycolysis is one of the important hallmarks of cancer cells and eukaryotic cells. In this study, we have investigated the relationship between blocking mitochondrial pyruvate carrier (MPC) with UK5099 and the metabolic alteration as well as stemness phenotype of prostatic cancer cells. It was found that blocking pyruvate transportation into mitochondrial attenuated mitochondrial oxidative phosphorylation (OXPHOS) and increased glycolysis. The UK5099 treated cells showed significantly higher proportion of side population (SP) fraction and expressed higher levels of stemness markers Oct3/4 and Nanog. Chemosensitivity examinations revealed that the UK5099 treated cells became more resistant to chemotherapy compared to the non-treated cells. These results demonstrate probably an intimate connection between metabolic reprogram and stem-like phenotype of LnCap cells in vitro. We propose that MPC blocker (UK5099) application may be an ideal model for Warburg effect studies, since it attenuates mitochondrial OXPHOS and increases aerobic glycolysis, a phenomenon typically reflected in the Warburg effect. We conclude that impaired mitochondrial OXPHOS and upregulated glycolysis are related with stem-like phenotype shift in prostatic cancer cells.

Role of AMPK signaling in mediating the anticancer effects of silibinin in esophageal squamous cell carcinoma.

PubMed

Li, Jin; Li, Bin; Xu, Wen Wen; Chan, Kwok Wah; Guan, Xin Yuan; Qin, Yan Ru; Lee, Nikki Pui Yue; Chan, Kin Tak; Law, Simon; Tsao, Sai Wah; Cheung, Annie Lm

2016-01-01

Emerging evidence suggests that activation of adenosine monophosphate-activated protein kinase (AMPK) may suppress cancer growth. Identification of novel AMPK activators is therefore crucial to exploit AMPK as a potential target for cancer prevention and treatment. We determined the expression status and role of AMPK in esophageal squamous cell carcinoma (ESCC) and investigated whether silibinin, a nontoxic natural product, could activate AMPK to inhibit ESCC development. Our results from 49 pairs of human ESCC and normal tissues showed that AMPK was constitutively inactive in the majority (69.4%) of ESCC. We found that silibinin induced apoptosis, and inhibited ESCC cell proliferation in vitro and tumorigenicity in vivo without any adverse effects. Silibinin also markedly suppressed the invasive potential of ESCC cells in vitro and their ability to form lung metastasis in nude mice. The anticancer effects of silibinin were abrogated by the presence of compound C or shRNA against AMPK. More importantly, silibinin enhanced the sensitivity of ESCC cells and tumors to the chemotherapeutic drugs, 5-fluorouracil and cisplatin. This preclinical study supports that AMPK is a valid therapeutic target and suggests that silibinin may be a potentially useful therapeutic agent and chemosensitizer for esophageal cancer.

Application of mitochondrial pyruvate carrier blocker UK5099 creates metabolic reprogram and greater stem-like properties in LnCap prostate cancer cells in vitro

PubMed Central

Zhong, Yali; Li, Xiaoran; Yu, Dandan; Li, Xiaoli; Li, Yaqing; Long, Yuan; Yuan, Yuan; Ji, Zhenyu; Zhang, Mingzhi; Wen, Jian-Guo; Nesland, Jahn M.; Suo, Zhenhe

2015-01-01

Aerobic glycolysis is one of the important hallmarks of cancer cells and eukaryotic cells. In this study, we have investigated the relationship between blocking mitochondrial pyruvate carrier (MPC) with UK5099 and the metabolic alteration as well as stemness phenotype of prostatic cancer cells. It was found that blocking pyruvate transportation into mitochondrial attenuated mitochondrial oxidative phosphorylation (OXPHOS) and increased glycolysis. The UK5099 treated cells showed significantly higher proportion of side population (SP) fraction and expressed higher levels of stemness markers Oct3/4 and Nanog. Chemosensitivity examinations revealed that the UK5099 treated cells became more resistant to chemotherapy compared to the non-treated cells. These results demonstrate probably an intimate connection between metabolic reprogram and stem-like phenotype of LnCap cells in vitro. We propose that MPC blocker (UK5099) application may be an ideal model for Warburg effect studies, since it attenuates mitochondrial OXPHOS and increases aerobic glycolysis, a phenomenon typically reflected in the Warburg effect. We conclude that impaired mitochondrial OXPHOS and upregulated glycolysis are related with stem-like phenotype shift in prostatic cancer cells. PMID:26413751

Glutathione S-transferase P1 (GSTP1) directly influences platinum drug chemosensitivity in ovarian tumour cell lines

PubMed Central

Sawers, L; Ferguson, M J; Ihrig, B R; Young, H C; Chakravarty, P; Wolf, C R; Smith, G

2014-01-01

Background: Chemotherapy response in ovarian cancer patients is frequently compromised by drug resistance, possibly due to altered drug metabolism. Platinum drugs are metabolised by glutathione S-transferase P1 (GSTP1), which is abundantly, but variably expressed in ovarian tumours. We have created novel ovarian tumour cell line models to investigate the extent to which differential GSTP1 expression influences chemosensitivity. Methods: Glutathione S-transferase P1 was stably deleted in A2780 and expression significantly reduced in cisplatin-resistant A2780DPP cells using Mission shRNA constructs, and MTT assays used to compare chemosensitivity to chemotherapy drugs used to treat ovarian cancer. Differentially expressed genes in GSTP1 knockdown cells were identified by Illumina HT-12 expression arrays and qRT–PCR analysis, and altered pathways predicted by MetaCore (GeneGo) analysis. Cell cycle changes were assessed by FACS analysis of PI-labelled cells and invasion and migration compared in quantitative Boyden chamber-based assays. Results: Glutathione S-transferase P1 knockdown selectively influenced cisplatin and carboplatin chemosensitivity (2.3- and 4.83-fold change in IC50, respectively). Cell cycle progression was unaffected, but cell invasion and migration was significantly reduced. We identified several novel GSTP1 target genes and candidate platinum chemotherapy response biomarkers. Conclusions: Glutathione S-transferase P1 has an important role in cisplatin and carboplatin metabolism in ovarian cancer cells. Inter-tumour differences in GSTP1 expression may therefore influence response to platinum-based chemotherapy in ovarian cancer patients. PMID:25010864

Selenium Nanoparticles Induce the Chemo-Sensitivity of Fluorouracil Nanoparticles in Breast and Colon Cancer Cells.

PubMed

Abd-Rabou, Ahmed A; Shalby, Aziza B; Ahmed, Hanaa H

2018-05-11

Drug resistance is a major challenge of breast and colon cancer therapies leading to treatment failure. The main objective of the current study is to investigate whether selenium nanoparticles (nano-Se) can induce the chemo-sensitivity of 5-fluorouracil (FU)-encapsulated poly (D, L-lactide-co-glycolide) nanoparticles (nano-FU) in breast and colon cancer cell lines. Nano-Se and nano-FU were synthesized and characterized, then applied individually or in combination upon MCF7, MDA-MB-231, HCT 116, and Caco-2 cancerous cell lines. Cytotoxicity, cellular glucose uptake, and apoptosis, as well as malondialdehyde (MDA), nitric oxide (NO), and zinc (Zn) levels, were investigated upon the different treatments. We have resulted that nano-FU induced cell death in MCF7 and Caco-2 more effectively than MDA-MB-231 and HCT 116 cell lines. Moreover, nano-FU plus nano-Se potentiate MCF7 and Caco-2 chemo-sensitivity were higher than MDA-MB-231 and HCT 116 cancerous cell lines. It is relevant to note that Se and FU nano-formulations inhibited cancer cell bioenergetics via glucose uptake slight blockage. Furthermore, nano-FU increased the levels of NO and MDA in media over cancer cells, while their combinations with nano-Se rebalance the redox status with Zn increment. We noticed that MCF7 cell line is sensitive, while MDA-MB-231 cell line is resistant to Se and nano-Se. This novel approach could be of great potential to enhance the chemo-sensitivity in breast and colon cancer cells.

Substance P Differentially Modulates Firing Rate of Solitary Complex (SC) Neurons from Control and Chronic Hypoxia-Adapted Adult Rats

PubMed Central

Nichols, Nicole L.; Powell, Frank L.; Dean, Jay B.; Putnam, Robert W.

2014-01-01

NK1 receptors, which bind substance P, are present in the majority of brainstem regions that contain CO2/H+-sensitive neurons that play a role in central chemosensitivity. However, the effect of substance P on the chemosensitive response of neurons from these regions has not been studied. Hypoxia increases substance P release from peripheral afferents that terminate in the caudal nucleus tractus solitarius (NTS). Here we studied the effect of substance P on the chemosensitive responses of solitary complex (SC: NTS and dorsal motor nucleus) neurons from control and chronic hypoxia-adapted (CHx) adult rats. We simultaneously measured intracellular pH and electrical responses to hypercapnic acidosis in SC neurons from control and CHx adult rats using the blind whole cell patch clamp technique and fluorescence imaging microscopy. Substance P significantly increased the basal firing rate in SC neurons from control and CHx rats, although the increase was smaller in CHx rats. However, substance P did not affect the chemosensitive response of SC neurons from either group of rats. In conclusion, we found that substance P plays a role in modulating the basal firing rate of SC neurons but the magnitude of the effect is smaller for SC neurons from CHx adult rats, implying that NK1 receptors may be down regulated in CHx adult rats. Substance P does not appear to play a role in modulating the firing rate response to hypercapnic acidosis of SC neurons from either control or CHx adult rats. PMID:24516602

Monoclonal antibody Zt/g4 targeting RON receptor tyrosine kinase enhances chemosensitivity of bladder cancer cells to Epirubicin by promoting G1/S arrest and apoptosis.

PubMed

Chen, Jun-Feng; Yu, Bi-Xia; Yu, Rui; Ma, Liang; Lv, Xiu-Yi; Cheng, Yue; Ma, Qi

2017-02-01

Epirubicin (EPI) is one of the most used intravesical chemotherapy agents after transurethral resection to non-muscle invasive bladder tumors (NMIBC) to prevent cancer recurrence and progression. However, even after resection of bladder tumors and intravesical chemotherapy, half of them will recur and progress. RON is a membrane tyrosine kinase receptor usually overexpressed in bladder cancer cells and associated with poor pathological features. This study aims to investigate the effects of anti-RON monoclonal antibody Zt/g4 on the chemosensitivity of bladder cells to EPI. After Zt/g4 treatment, cell cytotoxicity was significantly increased and cell invasion was markedly suppressed in EPI-treated bladder cancer cells. Further investigation indicated that combing Zt/g4 with EPI promoted cell G1/S-phase arrest and apoptosis, which are the potential mechanisms that RON signaling inhibition enhances chemosensitivity of EPI. Thus, combing antibody-based RON targeted therapy enhances the therapeutic effects of intravesical chemotherapy, which provides new strategy for further improvement of NMIBC patient outcomes.

Combined Gemcitabine and Metronidazole Is a Promising Therapeutic Strategy for Cancer Stem-like Cholangiocarcinoma.

PubMed

Kawamoto, Makoto; Umebayashi, Masayo; Tanaka, Hiroto; Koya, Norihiro; Nakagawa, Sinichiro; Kawabe, Ken; Onishi, Hideya; Nakamura, Masafumi; Morisaki, Takashi

2018-05-01

Metronidazole (MNZ) is a common antibiotic that exerts disulfiram-like effects when taken together with alcohol. However, the relationship between MNZ and aldehyde dehydrogenase (ALDH) activity remains unclear. This study investigated whether MNZ reduces cancer stemness by suppressing ALDH activity and accordingly reducing the malignancy of cholangiocarcinoma (CCA). We developed gemcitabine (GEM)-resistant TFK-1 cells and originally established CCA cell line from a patient with GEM-resistant CCA. Using these cell lines, we analyzed the impacts of MNZ for cancer stem cell markers, invasiveness, and chemosensitivity. MNZ reduced ALDH activity in GEM-resistant CCA cells, leading to decreased invasiveness and enhanced chemosensitivity. MNZ diminished the invasiveness by inducing mesenchymal-epithelial transition and enhancing chemosensitivity by increasing ENT1 (equilibrative nucleoside transporter 1) and reducing RRM1 (ribonucleotide reductase M1). MNZ reduced cancer stemness in GEM-resistant CCA cells. Combined GEM and MNZ would be a promising therapeutic strategy for cancer stem-like CAA. Copyright© 2018, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

Melatonin sensitizes human cervical cancer HeLa cells to cisplatin-induced cytotoxicity and apoptosis: effects on oxidative stress and DNA fragmentation.

PubMed

Pariente, Roberto; Pariente, José A; Rodríguez, Ana B; Espino, Javier

2016-01-01

Melatonin has antitumor activity via several mechanisms including its antiproliferative and pro-apoptotic effects as well as its potent antioxidant actions, although recent evidence has indicated that melatonin may perform pro-oxidant actions in tumor cells. Therefore, melatonin may be useful in the treatment of tumors in association with chemotherapy drugs. This study was intended to evaluate the in vitro effect of melatonin on the cytotoxic and pro-apoptotic actions of various chemotherapeutic agents in cervical cancer HeLa cells. Herein, we found that both melatonin and three of the chemotherapeutic drugs tested, namely cisplatin (CIS), 5-fluorouracil (5-FU), and doxorubicin, induced a decrease in HeLa cell viability. Furthermore, melatonin significantly increased the cytotoxic effect of such chemotherapeutic agents. Consistently, costimulation of HeLa cells with any chemotherapeutic agent in the presence of melatonin further increased caspase-3 activation, particularly in CIS- and 5-FU-challenged cells. Likewise, concomitant treatments with melatonin and CIS significantly enhanced the ratio of cells entering mitochondrial apoptosis due to reactive oxygen species (ROS) overproduction, substantially augmented the population of apoptotic cells, and markedly enlarged DNA fragmentation compared to the treatments with CIS alone. Nonetheless, melatonin only displayed moderate chemosensitizing effects in 5-FU-stimulated HeLa cells, as suggested by slight increments in the percentage of cells stimulated for ROS production and in the proportion of early apoptotic cells compared to the treatments with 5-FU alone. In summary, our findings provided evidence that in vitro melatonin strongly enhances CIS-induced cytotoxicity and apoptosis in HeLa cells and, hence, the indoleamine could be potentially applied to cervical cancer treatment as a powerful synergistic agent. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Stability of solutions of antineoplastic agents during preparation and storage for in vitro assays. General considerations, the nitrosoureas and alkylating agents.

PubMed

Bosanquet, A G

1985-01-01

In vitro drug sensitivity of tumour biopsies is currently being determined using a variety of methods. For these chemosensitivity assays many drugs are required at short notice, and this in turn means that the drugs must generally be stored in solution. There are, however, a number of potential problems associated with dissolving and storing drugs for in vitro use, which include (a) drug adsorption; (b) effects of freezing; (c) drug stability under the normal conditions of dilution and setting up of an in vitro assay; and (d) insolubility of drugs in normal saline (NS) or phosphate-buffered saline (PBS). These problems are considered in general, and some recommendations for use of solutions of drugs in in vitro assays are suggested. The nitrosoureas and alkylating agents are also investigated in greater detail in this respect. The nitrosoureas are found to be very labile in PBS at pH 7, with 5% degradation (t0.95) occurring in 10-50 min at room temperature. These values are increased about 10-fold on refrigeration and about 5- to 10-fold on reduction of the pH of the medium to pH 4-5. At pH 7 and room temperature, t0.95 is observed in under 1 h with the alkylating agents nitrogen mustard, chlorambucil, melphalan, 2,5-diaziridinyl-3,6-bis(2-hydroxyethylamino)-1,4-benzoquinone (BZQ), dibromodulcitol, dibromomannitol, treosulphan, and procarbazine. Of the other alkylating agents, 4-hydroperoxycylophosphamide (sometimes used in vitro in place of cyclophosphamide), busulphan, dianhydrogalactitol, aziridinylbenzoquinone (AZQ), and dacarbazine have a t0.95 of between 2 and 24 h, while ifosfamide and pentamethylmelamine are both stable in aqueous solution for greater than 7 days. About half the drugs studied in detail have been stored frozen in solution for in vitro use, although very little is known about their stability under these conditions.

Survivin inhibition via EZN-3042 in canine lymphoma and osteosarcoma.

PubMed

Shoeneman, J K; Ehrhart, E J; Charles, J B; Thamm, D H

2016-06-01

Canine lymphoma (LSA) and osteosarcoma (OS) have high mortality rates and remain in need of more effective therapeutic approaches. Survivin, an inhibitor of apoptosis (IAP) family member protein that inhibits apoptosis and drives cell proliferation, is commonly elevated in human and canine cancer. Survivin expression is a negative prognostic factor in dogs with LSA and OS, and canine LSA and OS cell lines express high levels of survivin. In this study, we demonstrate that survivin downregulation in canine LSA and OS cells using a clinically applicable locked nucleic acid antisense oligonucleotide (EZN-3042, Enzon Pharmaceuticals, Piscataway Township, NJ, USA) inhibits growth, induces apoptosis and enhances chemosensitivity in vitro, and inhibits survivin transcription and protein production in orthotopic canine OS xenografts. Our findings strongly suggest that survivin-directed therapies might be effective in treatment of canine LSA and OS and support evaluation of EZN-3042 in dogs with cancer. © 2014 John Wiley & Sons Ltd.

The serum miR-21 level serves as a predictor for the chemosensitivity of advanced pancreatic cancer, and miR-21 expression confers chemoresistance by targeting FasL.

PubMed

Wang, Peng; Zhuang, Liping; Zhang, Juan; Fan, Jie; Luo, Jianmin; Chen, Hao; Wang, Kun; Liu, Luming; Chen, Zhen; Meng, Zhiqiang

2013-06-01

miR-21 expression in cancer tissue has been reported to be associated with the clinical outcome and activity of gemcitabine in pancreatic cancer. However, resection is possible in only a minority of patients due to the advanced stages often present at the time of diagnosis, and safely obtaining sufficient quantities of pancreatic tumor tissue for molecular analysis is difficult at the unresectable stages. In this study, we investigated whether the serum level of miR-21 could be used as a predictor of chemosensitivity. We tested the levels of serum miR-21 in a cohort of 177 cases of advanced pancreatic cancer who received gemcitabine-based palliative chemotherapy. We found that a high level of miR-21 in the serum was significantly correlated with a shortened time-to-progression (TTP) and a lower overall survival (OS). The serum miR-21 level was an independent prognostic factor for both the TTP and the OS (HR 1.920; 95% CI, 1.274-2.903, p = 0.002 for TTP and HR 1.705; 95% CI, 1.147-2.535, p = 0.008 for OS). The results from a functional study showed that gemcitabine exposure down-regulated miR-21 expression and up-regulated FasL expression. The increased FasL expression following gemcitabine treatment induced cancer cell apoptosis, whereas the ectopic expression of miR-21 partially protected the cancer cells from gemcitabine-induced apoptosis. Additionally, we confirmed that FasL was a direct target of miR-21. Therefore, the serum level of miR-21 may serve as a predictor of chemosensitivity in advanced pancreatic cancer. Additionally, we identified a new mechanism of chemoresistance mediated by the effects of miR-21 on the FasL/Fas pathway. Copyright © 2012 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

Substance P–saporin lesion of neurons with NK1 receptors in one chemoreceptor site in rats decreases ventilation and chemosensitivity

PubMed Central

Nattie, Eugene E; Li, Aihua

2002-01-01

All medullary central chemoreceptor sites contain neurokinin-1 receptor immunoreactivity (NK1R-ir). We ask if NK1R-ir neurons and processes are involved in chemoreception. At one site, the retrotrapezoid nucleus/parapyramidal region (RTN/Ppy), we injected a substance P–saporin conjugate (SP-SAP; 0.1 pmol in 100 nl) to kill NK1R-ir neurons specifically, or SAP alone as a control. We made measurements for 15 days after the injections in two groups of rats. In group 1, with unilateral injections made in the awake state via a pre-implanted guide cannula, we compared responses within rats using initial baseline data. In group 2, with bilateral injections made under anaesthesia at surgery, we compared responses between SP-SAP- and SAP-treated rats. SP-SAP treatment reduced the volume of the RTN/Ppy region that contained NK1R-ir neuronal somata and processes by 44 % (group 1) and by 47 and 40 % on each side, respectively (group 2). Ventilation () and tidal volume (VT) were decreased during air breathing in sleep and wakefulness (group 2; P < 0.001; two-way ANOVA) and Pa,CO2 was increased (group 2; P < 0.05; Student's t test). When rats breathed an air mixture containing 7 % CO2 during sleep and wakefulness, and VT were lower (groups 1 and 2; P < 0.001; ANOVA) and the Δ in air containing 7 % CO2 compared to air was decreased by 28-30 % (group 1) and 17-22 % (group 2). SP-SAP-treated rats also slept less during air breathing. We conclude that neurons with NK1R-ir somata or processes in the RTN/Ppy region are either chemosensitive or they modulate chemosensitivity. They also provide a tonic drive to breathe and may affect arousal. PMID:12381830

Substance P-saporin lesion of neurons with NK1 receptors in one chemoreceptor site in rats decreases ventilation and chemosensitivity.

PubMed

Nattie, Eugene E; Li, Aihua

2002-10-15

All medullary central chemoreceptor sites contain neurokinin-1 receptor immunoreactivity (NK1R-ir). We ask if NK1R-ir neurons and processes are involved in chemoreception. At one site, the retrotrapezoid nucleus/parapyramidal region (RTN/Ppy), we injected a substance P-saporin conjugate (SP-SAP; 0.1 pmol in 100 nl) to kill NK1R-ir neurons specifically, or SAP alone as a control. We made measurements for 15 days after the injections in two groups of rats. In group 1, with unilateral injections made in the awake state via a pre-implanted guide cannula, we compared responses within rats using initial baseline data. In group 2, with bilateral injections made under anaesthesia at surgery, we compared responses between SP-SAP- and SAP-treated rats. SP-SAP treatment reduced the volume of the RTN/Ppy region that contained NK1R-ir neuronal somata and processes by 44 % (group 1) and by 47 and 40 % on each side, respectively (group 2). Ventilation (.V(E)) and tidal volume (V(T)) were decreased during air breathing in sleep and wakefulness (group 2; P < 0.001; two-way ANOVA) and P(a,CO2) was increased (group 2; P < 0.05; Student's t test). When rats breathed an air mixture containing 7 % CO(2) during sleep and wakefulness, .V(E) and V(T) were lower (groups 1 and 2; P < 0.001; ANOVA) and the Delta.V(E) in air containing 7 % CO(2) compared to air was decreased by 28-30 % (group 1) and 17-22 % (group 2). SP-SAP-treated rats also slept less during air breathing. We conclude that neurons with NK1R-ir somata or processes in the RTN/Ppy region are either chemosensitive or they modulate chemosensitivity. They also provide a tonic drive to breathe and may affect arousal.

Proton pump inhibitor chemosensitization in human osteosarcoma: from the bench to the patients’ bed

PubMed Central

2013-01-01

Background Major goals in translational oncology are to reduce systemic toxicity of current anticancer strategies and improve effectiveness. An extremely efficient cancer cell mechanism to avoid and/or reduce the effects of highly cytotoxic drugs is the establishment of an acidic microenvironment, an hallmark of all malignant tumors. The H + −rich milieu that anticancer drugs meet once they get inside the tumor leads to their protonation and neutralization, therefore hindering their access into tumor cells. We have previously shown that proton pump inhibitors (PPI) may efficiently counterattack this tumor advantage leading to a consistent chemosensitization of tumors. In this study, we investigated the effects of PPI in chemosensitizing osteosarcoma. Method MG-63 and Saos-2 cell lines were used as human osteosarcoma models. Cell proliferation after pretreatment with PPI and subsequent treatment with cisplatin was evaluated by using erythrosin B dye vital staining. Tumour growth was evaluated in xenograft treated with cisplatin after PPI pretreatment. Subsequently, a multi-centre historically controlled trial, was performed to evaluate the activity of a pre-treatment administration of PPIs as chemosensitizers during neoadjuvant chemotherapy based on methotrexate, cisplatin, and adriamycin. Results Preclinical experiments showed that PPI sensitize both human osteosarcoma cell lines and xenografts to cisplatin. A clinical study subsequently showed that pretreatment with PPI drug esomeprazole leads to an increase in the local effect of chemotherapy, as expressed by percentage of tumor necrosis. This was particularly evident in chondroblastic osteosarcoma, an histological subtype that normally shows a poor histological response. Notably, no significant increase in toxicity was recorded in PPI treated patients. Conclusion This study provides the first evidence that PPI may be beneficially added to standard regimens in combination to conventional chemotherapy. PMID:24156349

Proton pump inhibitor chemosensitization in human osteosarcoma: from the bench to the patients' bed.

PubMed

Ferrari, Stefano; Perut, Francesca; Fagioli, Franca; Brach Del Prever, Adalberto; Meazza, Cristina; Parafioriti, Antonina; Picci, Piero; Gambarotti, Marco; Avnet, Sofia; Baldini, Nicola; Fais, Stefano

2013-10-24

Major goals in translational oncology are to reduce systemic toxicity of current anticancer strategies and improve effectiveness. An extremely efficient cancer cell mechanism to avoid and/or reduce the effects of highly cytotoxic drugs is the establishment of an acidic microenvironment, an hallmark of all malignant tumors. The H +-rich milieu that anticancer drugs meet once they get inside the tumor leads to their protonation and neutralization, therefore hindering their access into tumor cells. We have previously shown that proton pump inhibitors (PPI) may efficiently counterattack this tumor advantage leading to a consistent chemosensitization of tumors. In this study, we investigated the effects of PPI in chemosensitizing osteosarcoma. MG-63 and Saos-2 cell lines were used as human osteosarcoma models. Cell proliferation after pretreatment with PPI and subsequent treatment with cisplatin was evaluated by using erythrosin B dye vital staining. Tumour growth was evaluated in xenograft treated with cisplatin after PPI pretreatment. Subsequently, a multi-centre historically controlled trial, was performed to evaluate the activity of a pre-treatment administration of PPIs as chemosensitizers during neoadjuvant chemotherapy based on methotrexate, cisplatin, and adriamycin. Preclinical experiments showed that PPI sensitize both human osteosarcoma cell lines and xenografts to cisplatin. A clinical study subsequently showed that pretreatment with PPI drug esomeprazole leads to an increase in the local effect of chemotherapy, as expressed by percentage of tumor necrosis. This was particularly evident in chondroblastic osteosarcoma, an histological subtype that normally shows a poor histological response. Notably, no significant increase in toxicity was recorded in PPI treated patients. This study provides the first evidence that PPI may be beneficially added to standard regimens in combination to conventional chemotherapy.

Manganese Superoxide Dismutase Is a Promising Target for Enhancing Chemosensitivity of Basal-Like Breast Carcinoma

PubMed Central

Kumar, Alan Prem; Loo, Ser Yue; Shin, Sung Won; Tan, Tuan Zea; Eng, Chon Boon; Singh, Rajeev; Putti, Thomas Choudary; Ong, Chee Wee; Salto-Tellez, Manuel; Goh, Boon Cher; Park, Joo In; Thiery, Jean Paul; Pervaiz, Shazib

2014-01-01

Abstract Aims: Although earlier reports highlighted a tumor suppressor role for manganese superoxide dismutase (MnSOD), recent evidence indicates increased expression in a variety of human cancers including aggressive breast carcinoma. In the present article, we hypothesized that MnSOD expression is significantly amplified in the aggressive breast carcinoma basal subtype, and targeting MnSOD could be an attractive strategy for enhancing chemosensitivity of this highly aggressive breast cancer subtype. Results: Using MDA-MB-231 and BT549 as a model of basal breast cancer cell lines, we show that knockdown of MnSOD decreased the colony-forming ability and sensitized the cells to drug-induced cell death, while drug resistance was associated with increased MnSOD expression. In an attempt to develop a clinically relevant approach to down-regulate MnSOD expression in patients with basal breast carcinoma, we employed activation of the peroxisome proliferator-activated receptor gamma (PPARγ) to repress MnSOD expression; PPARγ activation significantly reduced MnSOD expression, increased chemosensitivity, and inhibited tumor growth. Moreover, as a proof of concept for the clinical use of PPARγ agonists to decrease MnSOD expression, biopsies derived from breast cancer patients who had received synthetic PPARγ ligands as anti-diabetic therapy had significantly reduced MnSOD expression. Finally, we provide evidence to implicate peroxynitrite as the mechanism involved in the increased sensitivity to chemotherapy induced by MnSOD repression. Innovation and Conclusion: These data provide evidence to link increased MnSOD expression with the aggressive basal breast cancer, and underscore the judicious use of PPARγ ligands for specifically down-regulating MnSOD to increase the chemosensitivity of this subtype of breast carcinoma. Antioxid. Redox Signal. 20, 2326–2346. PMID:23964924

Generation of stable PDX derived cell lines using conditional reprogramming.

PubMed

Borodovsky, Alexandra; McQuiston, Travis J; Stetson, Daniel; Ahmed, Ambar; Whitston, David; Zhang, Jingwen; Grondine, Michael; Lawson, Deborah; Challberg, Sharon S; Zinda, Michael; Pollok, Brian A; Dougherty, Brian A; D'Cruz, Celina M

2017-12-06

Efforts to develop effective cancer therapeutics have been hindered by a lack of clinically predictive preclinical models which recapitulate this complex disease. Patient derived xenograft (PDX) models have emerged as valuable tools for translational research but have several practical limitations including lack of sustained growth in vitro. In this study, we utilized Conditional Reprogramming (CR) cell technology- a novel cell culture system facilitating the generation of stable cultures from patient biopsies- to establish PDX-derived cell lines which maintain the characteristics of the parental PDX tumor. Human lung and ovarian PDX tumors were successfully propagated using CR technology to create stable explant cell lines (CR-PDX). These CR-PDX cell lines maintained parental driver mutations and allele frequency without clonal drift. Purified CR-PDX cell lines were amenable to high throughput chemosensitivity screening and in vitro genetic knockdown studies. Additionally, re-implanted CR-PDX cells proliferated to form tumors that retained the growth kinetics, histology, and drug responses of the parental PDX tumor. CR technology can be used to generate and expand stable cell lines from PDX tumors without compromising fundamental biological properties of the model. It offers the ability to expand PDX cells in vitro for subsequent 2D screening assays as well as for use in vivo to reduce variability, animal usage and study costs. The methods and data detailed here provide a platform to generate physiologically relevant and predictive preclinical models to enhance drug discovery efforts.

Antitumor Activity and Mechanism of Action of the Cyclopenta[b]benzofuran, Silvestrol

PubMed Central

Cencic, Regina; Carrier, Marilyn; Galicia-Vázquez, Gabriela; Bordeleau, Marie-Eve; Sukarieh, Rami; Bourdeau, Annie; Brem, Brigitte; Teodoro, Jose G.; Greger, Harald; Tremblay, Michel L.; Porco, John A.; Pelletier, Jerry

2009-01-01

Background Flavaglines are a family of natural products from the genus Aglaia that exhibit anti-cancer activity in vitro and in vivo and inhibit translation initiation. They have been shown to modulate the activity of eIF4A, the DEAD-box RNA helicase subunit of the eukaryotic initiation factor (eIF) 4F complex, a complex that stimulates ribosome recruitment during translation initiation. One flavagline, silvestrol, is capable of modulating chemosensitivity in a mechanism-based mouse model. Methodology/Principal Findings Among a number of flavagline family members tested herein, we find that silvestrol is the more potent translation inhibitor among these. We find that silvestrol impairs the ribosome recruitment step of translation initiation by affecting the composition of the eukaryotic initiation factor (eIF) 4F complex. We show that silvestrol exhibits significant anticancer activity in human breast and prostate cancer xenograft models, and that this is associated with increased apoptosis, decreased proliferation, and inhibition of angiogenesis. We demonstrate that targeting translation by silvestrol results in preferential inhibition of weakly initiating mRNAs. Conclusions/Significance Our results indicate that silvestrol is a potent anti-cancer compound in vivo that exerts its activity by affecting survival pathways as well as angiogenesis. We propose that silvestrol mediates its effects by preferentially inhibiting translation of malignancy-related mRNAs. Silvestrol appears to be well tolerated in animals. PMID:19401772

Lack of association between deletion polymorphism of BIM gene and in vitro drug sensitivity in B-cell precursor acute lymphoblastic leukemia.

PubMed

Huang, Meixian; Miyake, Kunio; Kagami, Keiko; Abe, Masako; Shinohara, Tamao; Watanabe, Atsushi; Somazu, Shinpei; Oshiro, Hiroko; Goi, Kumiko; Goto, Hiroaki; Minegishi, Masayoshi; Iwamoto, Shotaro; Kiyokawa, Nobutaka; Sugita, Kanji; Inukai, Takeshi

2017-09-01

A deletion polymorphism in the BIM gene was identified as an intrinsic mechanism for resistance to tyrosine kinase inhibitor in chronic myeloid leukemia patients in East Asia. BIM is also involved in the responses to glucocorticoid and chemotherapy in acute lymphoblastic leukemia (ALL), suggesting a possible association between deletion polymorphism of BIM and the chemosensitivity of ALL. Thus, we analyzed 72 B-cell precursor (BCP)-ALL cell lines established from Japanese patients. Indeed, higher BIM gene expression was associated with good in vitro sensitivities to glucocorticoid and chemotherapeutic agents used in induction therapy. We also analyzed the methylation status of the BIM gene promoter by next generation sequencing of genome bisulfite PCR products, since genetic polymorphism could be insignificant when epigenetically inactivated. Hypermethylation of the BIM gene promoter was associated with lower BIM gene expression and poorer sensitivity to vincristine. Of note, however, the prevalence of a deletion polymorphism was not associated with the BIM gene expression level or drug sensitivities in BCP-ALL cell lines, in which the BIM gene was unmethylated. These observations suggest that an association of a deletion polymorphism of BIM and the response to induction therapy in BCP-ALL may be clinically minimal. Copyright © 2017. Published by Elsevier Ltd.

Understanding the Effectiveness of Natural Compound Mixtures in Cancer through Their Molecular Mode of Action

PubMed Central

Aung, Thazin Nwe; Qu, Zhipeng; Kortschak, R. Daniel; Adelson, David L.

2017-01-01

Many approaches to cancer management are often ineffective due to adverse reactions, drug resistance, or inadequate target specificity of single anti-cancer agents. In contrast, a combinatorial approach with the application of two or more anti-cancer agents at their respective effective dosages can achieve a synergistic effect that boosts cytotoxicity to cancer cells. In cancer, aberrant apoptotic pathways allow cells that should be killed to survive with genetic abnormalities, leading to cancer progression. Mutations in apoptotic mechanism arising during the treatment of cancer through cancer progression can consequently lead to chemoresistance. Natural compound mixtures that are believed to have multiple specific targets with minimal acceptable side-effects are now of interest to many researchers due to their cytotoxic and chemosensitizing activities. Synergistic interactions within a drug mixture enhance the search for potential molecular targets in cancer cells. Nonetheless, biased/flawed scientific evidence from natural products can suggest false positive therapeutic benefits during drug screening. In this review, we have taken these factors into consideration when discussing the evidence for these compounds and their synergistic therapeutic benefits in cancer. While there is limited evidence for clinical efficacy for these mixtures, in vitro data suggest that these preparations merit further investigation, both in vitro and in vivo. PMID:28304343

Understanding the Effectiveness of Natural Compound Mixtures in Cancer through Their Molecular Mode of Action.

PubMed

Aung, Thazin Nwe; Qu, Zhipeng; Kortschak, R Daniel; Adelson, David L

2017-03-17

Many approaches to cancer management are often ineffective due to adverse reactions, drug resistance, or inadequate target specificity of single anti-cancer agents. In contrast, a combinatorial approach with the application of two or more anti-cancer agents at their respective effective dosages can achieve a synergistic effect that boosts cytotoxicity to cancer cells. In cancer, aberrant apoptotic pathways allow cells that should be killed to survive with genetic abnormalities, leading to cancer progression. Mutations in apoptotic mechanism arising during the treatment of cancer through cancer progression can consequently lead to chemoresistance. Natural compound mixtures that are believed to have multiple specific targets with minimal acceptable side-effects are now of interest to many researchers due to their cytotoxic and chemosensitizing activities. Synergistic interactions within a drug mixture enhance the search for potential molecular targets in cancer cells. Nonetheless, biased/flawed scientific evidence from natural products can suggest false positive therapeutic benefits during drug screening. In this review, we have taken these factors into consideration when discussing the evidence for these compounds and their synergistic therapeutic benefits in cancer. While there is limited evidence for clinical efficacy for these mixtures, in vitro data suggest that these preparations merit further investigation, both in vitro and in vivo.

Self-assembled Multifunctional DNA Nanoflowers for the Circumvention of Multidrug Resistance in Targeted Anticancer Drug Delivery.

PubMed

Mei, Lei; Zhu, Guizhi; Qiu, Liping; Wu, Cuichen; Chen, Huapei; Liang, Hao; Cansiz, Sena; Lv, Yifan; Zhang, Xiaobing; Tan, Weihong

2015-11-01

Cancer chemotherapy has been impeded by side effects and multidrug resistance (MDR) partially caused by drug efflux from cancer cells, which call for targeted drug delivery systems additionally able to circumvent MDR. Here we report multifunctional DNA nanoflowers (NFs) for targeted drug delivery to both chemosensitive and MDR cancer cells and circumvent MDR in both leukemia and breast cancer cell models. NFs are self-assembled via liquid crystallization of DNA generated by Rolling Circle Replication, during which NFs are incorporated with aptamers for specific cancer cell recognition, fluorophores for bioimaging, and Doxorubicin (Dox)-binding DNA for drug delivery. NF sizes are tunable (down to ~200 nm in diameter), and the densely packed drug-binding motifs and porous intrastructures endow NFs with high drug loading capacity (71.4%, wt/wt). The Dox-loaded NFs (NF-Dox) are stable at physiological pH, yet drug release is facilitated in acidic or basic conditions. NFs deliver Dox into target chemosensitive and MDR cancer cells, preventing drug efflux and enhancing drug retention in MDR cells. Consequently, NF-Dox induces potent cytotoxicity in both target chemosensitive cells and MDR cells, but not nontarget cells, thus concurrently circumventing MDR and reducing side effects. Overall, these NFs are promising to circumvent MDR in targeted cancer therapy.

Thymoquinone chemosensitizes colon cancer cells through inhibition of NF-κB.

PubMed

Zhang, Lida; Bai, Yangqiu; Yang, Yuxiu

2016-10-01

In the present study, the effects and molecular mechanisms of thymoquinone (TQ) on colon cancer cells were investigated. Cell viability was determined using a Cell Counting Kit-8 assay, and the results revealed that treatment with TQ significantly decreased cell viability in COLO205 and HCT116 cells in a dose-dependent manner. TQ treatment additionally sensitized COLO205 and HCT116 cells to cisplatin therapy in a concentration-dependent manner. To investigate the molecular mechanisms of TQ action, western blot analysis was used to determine the levels of phosphorylated p65 and nuclear factor-κB (NF-κB)-regulated gene products vascular endothelial growth factor (VEGF), c-Myc and B-cell lymphoma 2 (Bcl-2). The results indicated that TQ treatment significantly decreased the level of phosphorylated p65 in the nucleus, which indicated the inhibition of NF-κB activation by TQ treatment. Treatment with TQ also decreased the expression levels of VEGF, c-Myc and Bcl-2. In addition, the inhibition of NF-κB activation with a specific inhibitor, pyrrolidine dithiocarbamate, potentiated the induction of cell death and caused a chemosensitization effect of TQ in colon cancer cells. Overall, the results of the present study suggested that TQ induced cell death and chemosensitized colon cancer cells by inhibiting NF-κB signaling.

Classical Hodgkin's lymphoma: the Lymphoma Study Association guidelines for relapsed and refractory adult patients eligible for transplant.

PubMed

Van Den Neste, Eric; Casasnovas, Olivier; André, Marc; Touati, Mohamed; Senecal, Delphine; Edeline, Véronique; Stamatoullas, Aspasia; Fornecker, Luc; Deau, Bénédicte; Gastinne, Thomas; Reman, Oumédaly; Gaillard, Isabelle; Borel, Cécile; Brice, Pauline; Fermé, Christophe

2013-08-01

The Hodgkin's Lymphoma Committee of the Lymphoma Study Association (LYSA) gathered in 2012 to prepare guidelines on the management of transplant-eligible patients with relapsing or refractory Hodgkin's lymphoma. The working group is made up of a multidisciplinary panel of experts with a significant background in Hodgkin's lymphoma. Each member of the panel of experts provided an interpretation of the evidence and a systematic approach to obtain consensus was used. Grades of recommendation were not required since levels of evidence are mainly based on phase II trials or standard practice. Data arising from randomized trials are emphasized. The final version was endorsed by the scientific council of the LYSA. The expert panel recommends a risk-adapted strategy (conventional treatment, or single/double transplantation and/or radiotherapy) based on three risk factors at progression (primary refractory disease, remission duration < 1 year, stage III/IV), and an early evaluation of salvage chemosensitivity, including (18)fluorodeoxy glucose-positron emission tomography interpreted according to the Deauville scoring system. Most relapsed or refractory Hodgkin's lymphoma patients chemosensitive to salvage should receive high-dose therapy and autologous stem-cell transplantation as standard. Efforts should be made to increase the proportion of chemosensitive patients by alternating non-cross-resistant chemotherapy lines or exploring the role of novel drugs.

Thymoquinone chemosensitizes colon cancer cells through inhibition of NF-κB

PubMed Central

Zhang, Lida; Bai, Yangqiu; Yang, Yuxiu

2016-01-01

In the present study, the effects and molecular mechanisms of thymoquinone (TQ) on colon cancer cells were investigated. Cell viability was determined using a Cell Counting Kit-8 assay, and the results revealed that treatment with TQ significantly decreased cell viability in COLO205 and HCT116 cells in a dose-dependent manner. TQ treatment additionally sensitized COLO205 and HCT116 cells to cisplatin therapy in a concentration-dependent manner. To investigate the molecular mechanisms of TQ action, western blot analysis was used to determine the levels of phosphorylated p65 and nuclear factor-κB (NF-κB)-regulated gene products vascular endothelial growth factor (VEGF), c-Myc and B-cell lymphoma 2 (Bcl-2). The results indicated that TQ treatment significantly decreased the level of phosphorylated p65 in the nucleus, which indicated the inhibition of NF-κB activation by TQ treatment. Treatment with TQ also decreased the expression levels of VEGF, c-Myc and Bcl-2. In addition, the inhibition of NF-κB activation with a specific inhibitor, pyrrolidine dithiocarbamate, potentiated the induction of cell death and caused a chemosensitization effect of TQ in colon cancer cells. Overall, the results of the present study suggested that TQ induced cell death and chemosensitized colon cancer cells by inhibiting NF-κB signaling. PMID:27698868

Metuzumab enhanced chemosensitivity and apoptosis in non-small cell lung carcinoma

PubMed Central

Feng, Fei; Wang, Bin; Sun, Xiuxuan; Zhu, Yumeng; Tang, Hao; Nan, Gang; Wang, Lijuan; Wu, Bo; Huhe, Muren; Liu, Shuangshuang; Diao, Tengyue; Hou, Rong; Zhang, Yang; Zhang, Zheng

2017-01-01

ABSTRACT Targeted therapeutics is used as an alternative treatment of non-small cell lung cancer (NSCLC); however, treatment effect is far from being satisfactory, and therefore identification of new targets is needed. We have previously shown that metuzumab inhibit tumor growth in vivo. The present study was performed to investigate the anti-tumor efficacy of metuzumab combined with gemcitabine and cisplatin (GP), paclitaxel and cisplatin (TP) or navelbine and cisplatin (NP) regimens in multiple NSCLC cell lines. Our results demonstrate that, in comparison to single agent metuzumab or GP treated cells, metuzumab combined with GP display inhibitory effects on tumor growth. Furthermore, we found that metuzumab elevated the sensitivity of cell lines to gemcitabine, which was identified by MTT assay. Flow cytometric analysis showed that metuzumab combined with gemcitabine (GEM) treatment led to an obvious G1 arrest and an elevated apoptosis in A549, NCI-H460 and NCI-H520 cells. Western blot analysis also demonstrated a significantly reduced level of cyclin D1, Bcl-2, and an obviously increase level of Bax and full-length caspase-3 in A549, NCI-H460 and NCI-H520 cells treated with metuzumab/gemcitabine combination in comparison with single agent treated cells. In addition, metuzumab/gemcitabine treated A549, NCI-H460 and NCI-H520 cells also demonstrated a significantly increase in deoxycytidine kinase (dCK) protein level compared with single agent metuzumab or gemcitabine treated cells. Xenograft models also demonstrated that this metuzumab/gemcitabine combination led to upregulation of dCK. Taken together, the mechanisms of metuzumab combined with GP repress tumor growth were that the combined treatment significantly inhibited the tumor cell proliferation, apoptosis and cell cycle in vitro and in vivo and at least partially by induction of dCK expression. Our results suggested that metuzumab could significantly enhance chemosensitivity of human NSCLC cells to gemcitabine. Metuzumab/gemcitabine combination treatment may be a potentially useful therapeutic regimen for NSCLC patients. PMID:28055291

A covalent PIN1 inhibitor selectively targets cancer cells by a dual mechanism of action

NASA Astrophysics Data System (ADS)

Campaner, Elena; Rustighi, Alessandra; Zannini, Alessandro; Cristiani, Alberto; Piazza, Silvano; Ciani, Yari; Kalid, Ori; Golan, Gali; Baloglu, Erkan; Shacham, Sharon; Valsasina, Barbara; Cucchi, Ulisse; Pippione, Agnese Chiara; Lolli, Marco Lucio; Giabbai, Barbara; Storici, Paola; Carloni, Paolo; Rossetti, Giulia; Benvenuti, Federica; Bello, Ezia; D'Incalci, Maurizio; Cappuzzello, Elisa; Rosato, Antonio; Del Sal, Giannino

2017-06-01

The prolyl isomerase PIN1, a critical modifier of multiple signalling pathways, is overexpressed in the majority of cancers and its activity strongly contributes to tumour initiation and progression. Inactivation of PIN1 function conversely curbs tumour growth and cancer stem cell expansion, restores chemosensitivity and blocks metastatic spread, thus providing the rationale for a therapeutic strategy based on PIN1 inhibition. Notwithstanding, potent PIN1 inhibitors are still missing from the arsenal of anti-cancer drugs. By a mechanism-based screening, we have identified a novel covalent PIN1 inhibitor, KPT-6566, able to selectively inhibit PIN1 and target it for degradation. We demonstrate that KPT-6566 covalently binds to the catalytic site of PIN1. This interaction results in the release of a quinone-mimicking drug that generates reactive oxygen species and DNA damage, inducing cell death specifically in cancer cells. Accordingly, KPT-6566 treatment impairs PIN1-dependent cancer phenotypes in vitro and growth of lung metastasis in vivo.

Precision medicine for cancer with next-generation functional diagnostics.

PubMed

Friedman, Adam A; Letai, Anthony; Fisher, David E; Flaherty, Keith T

2015-12-01

Precision medicine is about matching the right drugs to the right patients. Although this approach is technology agnostic, in cancer there is a tendency to make precision medicine synonymous with genomics. However, genome-based cancer therapeutic matching is limited by incomplete biological understanding of the relationship between phenotype and cancer genotype. This limitation can be addressed by functional testing of live patient tumour cells exposed to potential therapies. Recently, several 'next-generation' functional diagnostic technologies have been reported, including novel methods for tumour manipulation, molecularly precise assays of tumour responses and device-based in situ approaches; these address the limitations of the older generation of chemosensitivity tests. The promise of these new technologies suggests a future diagnostic strategy that integrates functional testing with next-generation sequencing and immunoprofiling to precisely match combination therapies to individual cancer patients.

Emodin enhances the chemosensitivity of endometrial cancer by inhibiting ROS-mediated Cisplatin-resistance.

PubMed

Ding, Ning; Zhang, Hong; Su, Shan; Ding, Yumei; Yu, Xiaohui; Tang, Yujie; Wang, Qingfang; Liu, Peishu

2017-12-18

Background Endometrial cancer is a common cause of death in gynecological malignancies. Cisplatin is a clinically chemotherapeutic agent. However, drug-resistance is the primary cause of treatment failure. Objective Emodin is commonly used clinically to increase the sensitivity of chemotherapeutic agents, yet whether Emodin promotes the role of Cisplatin in the treatment of endometrial cancer has not been studied. Method CCK-8 kit was utilized to determine the growth of two endometrial cancer cell lines, Ishikawa and HEC-IB. The apoptosis level of Ishikawa and HEC-IB cells was detected by Annexin V / propidium iodide double-staining assay. ROS level was detected by DCFH-DA and NADPH oxidase expression. Expressions of drug-resistant genes were examined by real-time PCR and Western blotting. Results Emodin combined with Cisplatin reduced cell growth and increased the apoptosis of endometrial cancer cells. Co-treatment of Emodin and Cisplatin increased chemosensitivity by inhibiting the expression of drug-resistant genes through reducing the ROS levels in endometrial cancer cells. In an endometrial cancer xenograft murine model, the tumor size was reduced and animal survival time was increased by co-treatment of Emodin and Cisplatin. Conclusion This study demonstrates that Emodin enhances the chemosensitivity of Cisplatin on endometrial cancer by inhibiting ROS-mediated expression of drug-resistance genes. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

A Modular Coassembly Approach to All-In-One Multifunctional Nanoplatform for Synergistic Codelivery of Doxorubicin and Curcumin

PubMed Central

Yang, Muyang; Yu, Lixia; Guo, Ruiwei; Dong, Anjie; Lin, Cunguo

2018-01-01

Synergistic combination therapy by integrating chemotherapeutics and chemosensitizers into nanoparticles has demonstrated great potential to reduce side effects, overcome multidrug resistance (MDR), and thus improve therapeutic efficacy. However, with regard to the nanocarriers for multidrug codelivery, it remains a strong challenge to maintain design simplicity, while incorporating the desirable multifunctionalities, such as coloaded high payloads, targeted delivery, hemodynamic stability, and also to ensure low drug leakage before reaching the tumor site, but simultaneously the corelease of drugs in the same cancer cell. Herein, we developed a facile modular coassembly approach to construct an all-in-one multifunctional multidrug delivery system for the synergistic codelivery of doxorubicin (DOX, chemotherapeutic agent) and curcumin (CUR, MDR modulator). The acid-cleavable PEGylated polymeric prodrug (DOX-h-PCEC), tumor cell-specific targeting peptide (CRGDK-PEG-PCL), and natural chemosensitizer (CUR) were ratiometrically assembled into in one single nanocarrier (CUR/DOX-h-PCEC@CRGDK NPs). The resulting CUR/DOX-h-PCEC@CRGDK NPs exhibited several desirable characteristics, such as efficient and ratiometric drug loading, high hemodynamic stability and low drug leakage, tumor intracellular acid-triggered cleavage, and subsequent intracellular simultaneous drug corelease, which are expected to maximize a synergistic effect of chemotherapy and chemosensitization. Collectively, the multifunctional nanocarrier is feasible for the creation of a robust nanoplatform for targeted multidrug codelivery and efficient MDR modulation. PMID:29543780

Paclitaxel stimulates chromosomal fusion and instability in cells with dysfunctional telomeres: Implication in multinucleation and chemosensitization

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

Park, Jeong-Eun; Woo, Seon Rang; Department of Biochemistry, College of Medicine, Korea University, Seoul 136-705

Research highlights: {yields} Paclitaxel serves as a stimulator of chromosomal fusion in cells in which telomeres are dysfunctional. {yields} Typical fusions involve p-arms, but paclitaxel-induced fusions occur between both q- and p-arms. {yields} Paclitaxel-stimulated fusions in cells in which telomeres are dysfunctional evoke prolonged G2/M cell cycle arrest and delay multinucleation. {yields} Upon telomere erosion, paclitaxel promotes chromosomal instability and subsequent apoptosis. {yields} Chromosomal fusion enhances paclitaxel chemosensitivity under telomere dysfunction. -- Abstract: The anticancer effect of paclitaxel is attributable principally to irreversible promotion of microtubule stabilization and is hampered upon development of chemoresistance by tumor cells. Telomere shortening, andmore » eventual telomere erosion, evoke chromosomal instability, resulting in particular cellular responses. Using telomerase-deficient cells derived from mTREC-/-p53-/- mice, here we show that, upon telomere erosion, paclitaxel propagates chromosomal instability by stimulating chromosomal end-to-end fusions and delaying the development of multinucleation. The end-to-end fusions involve both the p- and q-arms in cells in which telomeres are dysfunctional. Paclitaxel-induced chromosomal fusions were accompanied by prolonged G2/M cell cycle arrest, delayed multinucleation, and apoptosis. Telomere dysfunctional cells with mutlinucleation eventually underwent apoptosis. Thus, as telomere erosion proceeds, paclitaxel stimulates chromosomal fusion and instability, and both apoptosis and chemosensitization eventually develop.« less

Chemosensitive Phox2b-expressing neurons are crucial for hypercapnic ventilatory response in the nucleus tractus solitarius.

PubMed

Fu, Congrui; Xue, Jinyu; Wang, Ri; Chen, Jinting; Ma, Lan; Liu, Yixian; Wang, Xuejiao; Guo, Fang; Zhang, Yi; Zhang, Xiangjian; Wang, Sheng

2017-07-15

Central hypercapnic hypoventilation is highly prevalent in children suffering from congenital central hypoventilation syndrome (CCHS). Mutations of the gene for paired-like homeobox 2b (Phox2b) are aetiologically associated with CCHS and Phox2b is present in central components of respiratory chemoreflex, such as the nucleus tractus solitarius (NTS). Injection of the neurotoxin substance P-saporin into NTS destroys Phox2b-expressing neurons. Impaired hypercapnic ventilatory response caused by this neurotoxin is attributable to a loss of CO 2 -sensitive Phox2b-expressing NTS neurons. A subgroup of Phox2b-expressing neurons exhibits intrinsic chemosensitivity. A background K + channel-like current is partially responsible for such chemosensitivity in Phox2b-expressing neurons. The present study helps us better understand the mechanism of respiratory deficits in CCHS and potentially locates a brainstem site for development of precise clinical intervention. The nucleus tractus solitarius (NTS) neurons have been considered to function as central respiratory chemoreceptors. However, the common molecular marker defined for these neurons remains unknown. The present study investigated whether paired-like homeobox 2b (Phox2b)-expressing NTS neurons are recruited in hypercapnic ventilatory response (HCVR) and whether these neurons exhibit intrinsic chemosensitivity. HCVR was assessed using whole body plethysmography and neuronal chemosensitivity was examined by patch clamp recordings in brainstem slices or dissociated neurons from Phox2b-EGFP transgenic mice. Injection of the neurotoxin substance P-saporin (SSP-SAP) into NTS destroyed Phox2b-expressing neurons. Minute ventilation and tidal volume were both reduced by 13% during exposure to 8% CO 2 in inspired air when ∼13% of the Phox2b-expressing neurons were eliminated. However, a loss of ∼18% of these neurons was associated with considerable decreases in minute ventilation by ≥18% and in tidal volume by≥22% when challenged by ≥4% CO 2 . In both cases, breathing frequency was unaffected. Most CO 2 -activated neurons were immunoreactive to Phox2b. In brainstem slices, ∼43% of Phox2b-expressing neurons from Phox2b-EGFP mice displayed a sustained or transient increase in firing rate during physiological acidification (pH 7.0 or 8% CO 2 ). Such a response was also present in dissociated neurons in favour of an intrinsic property. In voltage clamp recordings, a background K + channel-like current was found in a subgroup of Phox2b-expressing neurons. Thus, the respiratory deficits caused by injection of SSP-SAP into the NTS are attributable to proportional lesions of CO 2 /H + -sensitive Phox2b-expressing neurons. © 2017 The Authors. The Journal of Physiology © 2017 The Physiological Society.

miR-128 modulates chemosensitivity and invasion of prostate cancer cells through targeting ZEB1.

PubMed

Sun, Xianglun; Li, Youkong; Yu, Jie; Pei, Hong; Luo, Pengcheng; Zhang, Jie

2015-05-01

Recent reports strongly suggest the profound role of miRNAs in cancer therapeutic response and progression, including invasion and metastasis. The sensitivity to therapy and invasion is the major obstacle for successful treatment in prostate cancer. We aimed to investigate the regulative effect of miR-128/zinc-finger E-box-binding homeobox 1 axis on prostate cancer cell chemosensitivity and invasion. The miR-128 expression pattern of prostate cancer cell lines and tissues was detected by real-time reverse transcriptase-polymerase chain reaction, while the mRNA and protein expression levels of zinc-finger E-box-binding homeobox 1 were measured by real-time reverse transcriptase-polymerase chain reaction and western blot assay, respectively. Dual-luciferase reporter gene assay was used to find the direct target of miR-128. Furthermore, prostate cancer cells were treated with miR-128 mimic or zinc-finger E-box-binding homeobox 1-siRNA, and then the cells' chemosensitivity and invasion were detected by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and transwell assay, respectively. We found miR-128 expression obviously decreased in prostate cancer tissues compared with paired normal tissues. Restored miR-128 expression sensitized prostate cancer cells to cisplatin and inhibited the invasion. Furthermore, there was an inverse expression pattern between miR-128 and zinc-finger E-box-binding homeobox 1 in prostate cancer cells and tissues, and zinc-finger E-box-binding homeobox 1 was identified as a direct target of miR-128 in prostate cancer. Knockdown of zinc-finger E-box-binding homeobox 1 expression efficiently sensitized prostate cancer cells to cisplatin and inhibited the invasion. However, ectopic zinc-finger E-box-binding homeobox 1 expression impaired the effects of miR-128 on chemosensitivity and invasion in prostate cancer cells. miR-128 functions as a potential cancer suppressor in prostate cancer progression and rational therapeutic strategies for prostate cancer would be developed based on miR-128/zinc-finger E-box-binding homeobox 1 axis. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Modulators of sensitivity and resistance to inhibition of PI3K identified in a pharmacogenomic screen of the NCI-60 human tumor cell line collection.

PubMed

Kwei, Kevin A; Baker, Joffre B; Pelham, Robert J

2012-01-01

The phosphoinositide 3-kinase (PI3K) signaling pathway is significantly altered in a wide variety of human cancers, driving cancer cell growth and survival. Consequently, a large number of PI3K inhibitors are now in clinical development. To begin to improve the selection of patients for treatment with PI3K inhibitors and to identify de novo determinants of patient response, we sought to identify and characterize candidate genomic and phosphoproteomic biomarkers predictive of response to the selective PI3K inhibitor, GDC-0941, using the NCI-60 human tumor cell line collection. In this study, sixty diverse tumor cell lines were exposed to GDC-0941 and classified by GI(50) value as sensitive or resistant. The most sensitive and resistant cell lines were analyzed for their baseline levels of gene expression and phosphorylation of key signaling nodes. Phosphorylation or activation status of both the PI3K-Akt signaling axis and PARP were correlated with in vitro response to GDC-0941. A gene expression signature associated with in vitro sensitivity to GDC-0941 was also identified. Furthermore, in vitro siRNA-mediated silencing of two genes in this signature, OGT and DDN, validated their role in modulating sensitivity to GDC-0941 in numerous cell lines and begins to provide biological insights into their role as chemosensitizers. These candidate biomarkers will offer useful tools to begin a more thorough understanding of determinants of patient response to PI3K inhibitors and merit exploration in human cancer patients treated with PI3K inhibitors.

Modulators of Sensitivity and Resistance to Inhibition of PI3K Identified in a Pharmacogenomic Screen of the NCI-60 Human Tumor Cell Line Collection

PubMed Central

Kwei, Kevin A.; Baker, Joffre B.; Pelham, Robert J.

2012-01-01

The phosphoinositide 3-kinase (PI3K) signaling pathway is significantly altered in a wide variety of human cancers, driving cancer cell growth and survival. Consequently, a large number of PI3K inhibitors are now in clinical development. To begin to improve the selection of patients for treatment with PI3K inhibitors and to identify de novo determinants of patient response, we sought to identify and characterize candidate genomic and phosphoproteomic biomarkers predictive of response to the selective PI3K inhibitor, GDC-0941, using the NCI-60 human tumor cell line collection. In this study, sixty diverse tumor cell lines were exposed to GDC-0941 and classified by GI50 value as sensitive or resistant. The most sensitive and resistant cell lines were analyzed for their baseline levels of gene expression and phosphorylation of key signaling nodes. Phosphorylation or activation status of both the PI3K-Akt signaling axis and PARP were correlated with in vitro response to GDC-0941. A gene expression signature associated with in vitro sensitivity to GDC-0941 was also identified. Furthermore, in vitro siRNA-mediated silencing of two genes in this signature, OGT and DDN, validated their role in modulating sensitivity to GDC-0941 in numerous cell lines and begins to provide biological insights into their role as chemosensitizers. These candidate biomarkers will offer useful tools to begin a more thorough understanding of determinants of patient response to PI3K inhibitors and merit exploration in human cancer patients treated with PI3K inhibitors. PMID:23029544

ILs-3, 6 and 11 increase, but ILs-10 and 24 decrease stemness of human prostate cancer cells in vitro.

PubMed

Yu, Dandan; Zhong, Yali; Li, Xiaoran; Li, Yaqing; Li, Xiaoli; Cao, Jing; Fan, Huijie; Yuan, Yuan; Ji, Zhenyu; Qiao, Baoping; Wen, Jian-Guo; Zhang, Mingzhi; Kvalheim, Gunnar; Nesland, Jahn M; Suo, Zhenhe

2015-12-15

Cancer stem cells (CSCs) are associated with cancer recurrence and metastasis. Prostate cancer cells often metastasize to the bone with a complex microenvironment of cytokines favoring cell survival. In this study, the cell stemness influence of a group of interleukins including IL-3, 6, 10, 11 and 24 on human prostate cancer cell lines LNCaP and PC-3 was explored in vitro. Sulforhodamine B(SRB) and 5-ethynyl-2'-deoxyuridine (EdU) assays were applied to examine the effect on cell proliferation, and wound healing and transwell assays were used for migration and invasion studies, in addition to colony formation, Western blotting and flowcytometry for the expression of stemness factors and chemotherapy sensitivity. We observed that ILs-3, 6 and 11 stimulated while ILs-10 and 24 inhibited the growth, invasion and migration of both cell lines. Interestingly, ILs-3, 6 and 11 significantly promoted colony formation and increased the expression of SOX2, CD44 and ABCG2 in both prostate cancer cell lines. However, ILs-10 and 24 showed the opposite effect on the expression of these factors. In line with the above findings, treatment with either IL-3 or IL-6 or IL-11 decreased the chemosensitivity to docetaxel while treatment with either IL-10 or IL-24 increased the sensitivity of docetaxel chemotherapy. In conclusion, our results suggest that ILs-3, 6 and 11 function as tumor promoters while ILs-10 and 24 function as tumor suppressors in the prostate cancer cell lines PC-3 and LNCaP in vitro, and such differences may attribute to their different effect on the stemness of PCa cells.

Shenmai injection enhances the cytotoxicity of chemotherapeutic drugs against colorectal cancers via improving their subcellular distribution

PubMed Central

Liu, Wen-yue; Zhang, Jing-wei; Yao, Xue-quan; Jiang, Chao; He, Ji-chao; Ni, Pin; Liu, Jia-li; Chen, Qian-ying; Li, Qing-ran; Zang, Xiao-jie; Yao, Lan; Liu, Ya-zhong; Wang, Mu-lan; Shen, Pei-qiang; Wang, Guang-ji; Zhou, Fang

2017-01-01

Shenmai injection (SMI) is a Chinese patent-protected injection, which was mainly made of Red Ginseng and Radix Ophiopogonis and widely used for treating coronary heart disease and tumors by boosting Qi and nourishing Yin. In this study we examined whether SMI could produce direct synergetic effects on the cytoxicity of adriamycin (ADR) and paclitaxel (PTX) in colorectal cancers in vivo and in vitro, and explored the underlying pharmacokinetic mechanisms. BALB/c nude mice with LoVo colon cancer xenografts were intraperitoneally injected with ADR (2 mg·kg−1·3d−1) or PTX (7.5 mg·kg−1·3d−1) with or without SMI (0.01 mL·g−1·d−1) for 13 d. Co-administration of SMI significantly enhanced the chemotherapeutic efficacy of ADR and PTX, whereas administration of SMI alone at the given dosage did not produce visible anti-cancer effects, The chemosensitizing action of SMI was associated with increased concentrations of ADR and PTX in the plasma and tumors. In Caco-2 and LoVo cells in vitro, co-treatment with SMI (2 μL/mL) significantly enhanced the cytotoxicity of ADR and PTX, and resulted in some favorable pharmacokinetic changes in the subcellular distribution of ADR and PTX. In addition, SMI-induced intracellular accumulation of ADR was closely correlated with the increased expression levels of P-glycoprotein in 4 colon cancer cell lines (r2=+0.8558). SMI enhances the anti-cancer effects of ADR and PTX in colon cancers in vivo and in vitro by improving the subcellular distributions of ADR and PTX. PMID:27867186

ILs-3, 6 and 11 increase, but ILs-10 and 24 decrease stemness of human prostate cancer cells in vitro

PubMed Central

Yu, Dandan; Zhong, Yali; Li, Xiaoran; Li, Yaqing; Li, Xiaoli; Cao, Jing; Fan, Huijie; Yuan, Yuan; Ji, Zhenyu; Qiao, Baoping; Wen, Jian-Guo; Zhang, Mingzhi; Kvalheim, Gunnar; Nesland, Jahn M.; Suo, Zhenhe

2015-01-01

Cancer stem cells (CSCs) are associated with cancer recurrence and metastasis. Prostate cancer cells often metastasize to the bone with a complex microenvironment of cytokines favoring cell survival. In this study, the cell stemness influence of a group of interleukins including IL-3, 6, 10, 11 and 24 on human prostate cancer cell lines LNCaP and PC-3 was explored in vitro. Sulforhodamine B(SRB) and 5-ethynyl-2′-deoxyuridine (EdU) assays were applied to examine the effect on cell proliferation, and wound healing and transwell assays were used for migration and invasion studies, in addition to colony formation, Western blotting and flowcytometry for the expression of stemness factors and chemotherapy sensitivity. We observed that ILs-3, 6 and 11 stimulated while ILs-10 and 24 inhibited the growth, invasion and migration of both cell lines. Interestingly, ILs-3, 6 and 11 significantly promoted colony formation and increased the expression of SOX2, CD44 and ABCG2 in both prostate cancer cell lines. However, ILs-10 and 24 showed the opposite effect on the expression of these factors. In line with the above findings, treatment with either IL-3 or IL-6 or IL-11 decreased the chemosensitivity to docetaxel while treatment with either IL-10 or IL-24 increased the sensitivity of docetaxel chemotherapy. In conclusion, our results suggest that ILs-3, 6 and 11 function as tumor promoters while ILs-10 and 24 function as tumor suppressors in the prostate cancer cell lines PC-3 and LNCaP in vitro, and such differences may attribute to their different effect on the stemness of PCa cells. PMID:26528857

Restoring sensitivity to oxaliplatin by a novel approach in gemcitabine-resistant pancreatic cancer cells in vitro and in vivo

PubMed Central

Banerjee, Sanjeev; Kong, Dejuan; Azmi, Asfar S.; Wang, Zhiwei; Ahmad, Aamir; Sethi, Seema; Sarkar, Fazlul H.

2011-01-01

Oxaliplatin (OxP) has been used in combination therapy with gemcitabine for the treatment of pancreatic cancer (PC), but the beneficial effect was marginal, which is believed to be due to de novo and acquired drug resistance of PC. Here, we report our in vitro and in vivo preclinical evidence in support of chemosensitization of drug-resistant cells by a nontoxic chemopreventive agent (genistein). Genistein pretreatment together with low concentration of OxP showed significant reduction in cell viability and colony formation concomitant with increased apoptosis (p < 0.01), which was highly synergistic. Drug resistance of PC is allegedly linked with both constitutive and OxP-induced activation of NF-κB, and we found that inactivation of (nuclear factor kappa B) NF-κB by genistein before treatment of cells with OxP was required for cell killing, which was consistent with the downregulation of NF-κB and its downstream antiapoptotic genes (Bcl-2, XIAPs and survivin). Most importantly, our in vivo experiments using orthotopic mouse model showed significant reduction in tumor size (p < 0.01) and reduction of locoregional lymph node metastasis by combination treatment. These results were also consistent with inactivation of NF-κB and the downregulation of NF-κB downstream genes, decreased proliferation marker (Ki-67) and increased apoptosis (TUNEL) in tumor remnants, all of which was consistent with in vitro findings. From these results, we conclude that genistein sensitizes drug-resistant PC to OxP, which is mechanistically linked with inactivation of NF-κB signaling, resulting in greater antitumor effects, and thus our data suggest that this approach could be useful in improving the treatment outcome for patients diagnosed with PC. PMID:20824697

Establishment and characterization of a penile cancer cell line, penl1, with a deleterious TP53 mutation as a paradigm of HPV-negative penile carcinogenesis.

PubMed

Chen, Jieping; Yao, Kai; Li, Zaishang; Deng, Chuangzhong; Wang, Liangjiao; Yu, Xingsu; Liang, Peili; Xie, Qiankun; Chen, Peng; Qin, Zike; Ye, Yunlin; Liu, Zhuowei; Zhou, Fangjian; Zhang, Zhenfeng; Han, Hui

2016-08-09

To establish penile cancer (PeCa) cell lines for the study of molecular mechanisms of carcinogenesis and testing therapeutic reagents. We successfully established two PeCa cell lines from fresh tumor tissues from 21 cases. One cell line named Penl1 was isolated from a lymph node metastasis (LNM) of penile squamous cell carcinoma (PeSCC), usual type and comprehensively characterized here. Our in-depth characterization analysis of the Penl1 cell line included morphology, tumorigenicity, genetic characteristics, protein expression, biology, and chemosensitivity. Penl1 was authenticated by single tandem repeat (STR) DNA typing. Comparative histomorphology, genetic characteristics, and protein expression patterns revealed essential similarities between the cell line and its corresponding LNM. In-depth characterization analysis of Penl1 cell line revealed tumorigenicity in immunodeficient mice, negative human papilloma virus (HPV) and mycoplasma infection, TP53 mutations and sensitivity to cisplatin and epirubicin. STR DNA typing did not match any cell lines within three international cell banks. The limitation of this study is that one patient cannot represent the complete heterogeneity of PeCa, especially primary tumor. We established and characterized an HPV-negative and moderately differentiated PeCa cell model with a TP53 missense mutation from a PeSCC, usual type patient. A preliminarily study of carcinogenesis and chemosensitivity suggests that this cell model carries a tumor suppressor gene mutation and is sensitive to chemotherapy drugs.

Establishment and characterization of a penile cancer cell line, penl1, with a deleterious TP53 mutation as a paradigm of HPV-negative penile carcinogenesis

PubMed Central

Li, Zaishang; Deng, Chuangzhong; Wang, Liangjiao; Yu, Xingsu; Liang, Peili; Xie, Qiankun; Chen, Peng; Qin, Zike; Ye, Yunlin; Liu, Zhuowei; Zhou, Fangjian; Zhang, Zhenfeng; Han, Hui

2016-01-01

Purpose To establish penile cancer (PeCa) cell lines for the study of molecular mechanisms of carcinogenesis and testing therapeutic reagents. Materials and Methods We successfully established two PeCa cell lines from fresh tumor tissues from 21 cases. One cell line named Penl1 was isolated from a lymph node metastasis (LNM) of penile squamous cell carcinoma (PeSCC), usual type and comprehensively characterized here. Our in-depth characterization analysis of the Penl1 cell line included morphology, tumorigenicity, genetic characteristics, protein expression, biology, and chemosensitivity. Penl1 was authenticated by single tandem repeat (STR) DNA typing. Results Comparative histomorphology, genetic characteristics, and protein expression patterns revealed essential similarities between the cell line and its corresponding LNM. In-depth characterization analysis of Penl1 cell line revealed tumorigenicity in immunodeficient mice, negative human papilloma virus (HPV) and mycoplasma infection, TP53 mutations and sensitivity to cisplatin and epirubicin. STR DNA typing did not match any cell lines within three international cell banks. The limitation of this study is that one patient cannot represent the complete heterogeneity of PeCa, especially primary tumor. Conclusions We established and characterized an HPV-negative and moderately differentiated PeCa cell model with a TP53 missense mutation from a PeSCC, usual type patient. A preliminarily study of carcinogenesis and chemosensitivity suggests that this cell model carries a tumor suppressor gene mutation and is sensitive to chemotherapy drugs. PMID:27351128

Nematocyst discharge in Pelagia noctiluca (Cnidaria, Scyphozoa) oral arms can be affected by lidocaine, ethanol, ammonia and acetic acid.

PubMed

Morabito, Rossana; Marino, Angela; Dossena, Silvia; La Spada, Giuseppa

2014-06-01

Nematocyst discharge and concomitant delivery of toxins is triggered to perform both defence and predation strategies in Cnidarians, and may lead to serious local and systemic reactions in humans. Pelagia noctiluca (Cnidaria, Scyphozoa) is a jellyfish particularly abundant in the Strait of Messina (Italy). After accidental contact with this jellyfish, not discharged nematocysts or even fragments of tentacles or oral arms may tightly adhere to the human skin and, following discharge, severely increase pain and the other adverse consequences of the sting. The aim of the present study is to verify if the local anesthetic lidocaine and other compounds, like alcohols, acetic acid and ammonia, known to provide pain relief after jellyfish stings, may also affect in situ discharge of nematocysts. Discharge was induced by a combined physico-chemical stimulation of oral arms by chemosensitizers (such as N-acetylated sugars, aminoacids, proteins and nucleotides), in the presence or absence of 1% lidocaine, 70% ethanol, 5% acetic acid or 20% ammonia, followed by mechanical stimulation by a non-vibrating test probe. The above mentioned compounds failed to induce discharge per se, and dramatically impaired the chemosensitizer-induced discharge response. We therefore suggest that prompt local treatment of the stung epidermis with lidocaine, acetic acid, ethanol and ammonia may provide substantial pain relief and help in reducing possible harmful local and systemic adverse reaction following accidental contact with P. noctiluca specimens. Copyright © 2014 Elsevier Ltd. All rights reserved.

Regulation of HIF-1α signaling and chemoresistance in acute lymphocytic leukemia under hypoxic conditions of the bone marrow microenvironment

PubMed Central

Frolova, Olga; Samudio, Ismael; Benito, Juliana Maria; Jacamo, Rodrigo; Kornblau, Steven M.; Markovic, Ana; Schober, Wendy; Lu, Hongbo; Qiu, Yi Hua; Buglio, Daniela; McQueen, Teresa; Pierce, Sherry; Shpall, Elizabeth; Konoplev, Sergej; Thomas, Deborah; Kantarjian, Hagop; Lock, Richard; Andreeff, Michael; Konopleva, Marina

2012-01-01

Overcoming resistance to chemotherapy is the main therapeutic challenge in the treatment of acute lymphocytic leukemia (ALL). Interactions between leukemia cells and the microenvironment promote leukemia cell survival and confer resistance to chemotherapy. Hypoxia is an integral component of bone marrow (BM) microenvironment. Hypoxia-inducible factor-1α (HIF-1), a key regulator of the cellular response to hypoxia, regulates cell growth and metabolic adaptation to hypoxia. HIF-1α expression, analyzed by Reverse Phase Protein Arrays in 92 specimens from newly diagnosed patients with pre-B-ALL, had a negative prognostic impact on survival (p = 0.0025). Inhibition of HIF-1α expression by locked mRNA antagonist (LNA) promoted chemosensitivity under hypoxic conditions, while pharmacological or genetic stabilization of HIF-1α under normoxia inhibited cell growth and reduced apoptosis induction by chemotherapeutic agents. Co-culture of pre-B ALL or REH cells with BM-derived mesenchymal stem cells (MSC) under hypoxia resulted in further induction of HIF-1α protein and acquisition of the glycolytic phenotype, in part via stroma-induced AKT/mTOR signaling. mTOR blockade with everolimus reduced HIF-1α expression, diminished glucose uptake and glycolytic rate and partially restored the chemosensitivity of ALL cells under hypoxia/stroma co-cultures. Hence, mTOR inhibition or blockade of HIF-1α-mediated signaling may play an important role in chemosensitization of ALL cells under hypoxic conditions of the BM microenvironment. PMID:22785211

Using patient-derived xenograft models of colorectal liver metastases to predict chemosensitivity.

PubMed

Brown, Kai M; Xue, Aiqun; Julovi, Sohel M; Gill, Anthony J; Pavlakis, Nick; Samra, Jaswinder S; Smith, Ross C; Hugh, Thomas J

2018-07-01

Few in vivo models for colorectal cancer have been demonstrated to show external validity by accurately predicting clinical patient outcomes. Patient-derived xenograft (PDX) models of cancer have characteristics that might provide a form of translational research leading to personalized cancer care. The aim of this pilot study was to assess the feasibility of using PDXs as a platform for predicting patient colorectal liver metastases responses, in this case by correlating PDX and patient tumor responses to either folinic acid, fluorouracil plus oxaliplatin or folinic acid, fluorouracil plus irinotecan-based regimens. Sixteen patients underwent potentially curative resection of colorectal liver metastases, and tumors were grafted into NOD.CB17-Prkdc scid /Arc mice. Mice were divided into groups to determine relative tumor growth in response to treatment. Tumors were analyzed by immunohistochemistry for Ki67 and Excision repair cross-complementation group 1. An engraftment rate of 81% was achieved. Overall, there was a 67% positive match rate between eligible patient and PDX chemosensitivity profiles. There was a significant difference in relative decrease in Ki67 expression between sensitive/stable versus resistant PDXs for both treatment regimens. There was no statistically significant correlation between baseline ERCC1 expression and response to Oxaliplatin + 5-Fluorouracil in the PDXs. This pilot study supports the feasibility of using PDX models of advanced colorectal cancer in larger studies to potentially predict patient chemosensitivity profiles. Copyright © 2018 Elsevier Inc. All rights reserved.

Berberine Reverses Hypoxia-induced Chemoresistance in Breast Cancer through the Inhibition of AMPK- HIF-1α

PubMed Central

Pan, Yue; Shao, Dan; Zhao, Yawei; Zhang, Fan; Zheng, Xiao; Tan, Yongfei; He, Kan; Li, Jing; Chen, Li

2017-01-01

Breast cancer is the most common type of cancer and the second leading cause of cancer death in American women. Chemoresistance is common and inevitable after a variable period of time. Therefore, chemosensitization is a necessary strategy on drug-resistant breast cancer. In this study, MCF-7 breast cancer cell was cultured under hypoxia for a week to induce the resistance to doxorubincin (DOX). The effect of different doses of berberine, a traditional Chinese medicine, on DOX sensitivity to MFC-7/hypoxia cells was observed. We found that hypoxia increased DOX resistance on breast cancer cells with the AMPK activation. Low-dose berberine could resensitize DOX chemosensitivity in MCF-7/hypoxia cell, however, high-dose berberine directly induced apoptosis. The intriguing fact was that the protein expressions of AMPK and HIF-1α were down-regulated by berberine, either low dose or high dose. But the downstream of HIF-1α occurred the bifurcation dependent on the dosage of berberine: AMPK-HIF-1α-P-gp inactivation played a crucial role on the DOX chemosensitivity of low-dose berberine, while AMPK-HIF-1α downregulaton inducing p53 activation led to apoptosis in high-dose berberine. These results were consistent to the transplanted mice model bearing MCF-7 drug-resistance tumor treated by berberine combined with DOX or high-dose berberine alone. This work shed light on a potentially therapeutic attempt to overcome drug-resistant breast cancer. PMID:28656004

Berberine Reverses Hypoxia-induced Chemoresistance in Breast Cancer through the Inhibition of AMPK- HIF-1α.

PubMed

Pan, Yue; Shao, Dan; Zhao, Yawei; Zhang, Fan; Zheng, Xiao; Tan, Yongfei; He, Kan; Li, Jing; Chen, Li

2017-01-01

Breast cancer is the most common type of cancer and the second leading cause of cancer death in American women. Chemoresistance is common and inevitable after a variable period of time. Therefore, chemosensitization is a necessary strategy on drug-resistant breast cancer. In this study, MCF-7 breast cancer cell was cultured under hypoxia for a week to induce the resistance to doxorubincin (DOX). The effect of different doses of berberine, a traditional Chinese medicine, on DOX sensitivity to MFC-7/hypoxia cells was observed. We found that hypoxia increased DOX resistance on breast cancer cells with the AMPK activation. Low-dose berberine could resensitize DOX chemosensitivity in MCF-7/hypoxia cell, however, high-dose berberine directly induced apoptosis. The intriguing fact was that the protein expressions of AMPK and HIF-1α were down-regulated by berberine, either low dose or high dose. But the downstream of HIF-1α occurred the bifurcation dependent on the dosage of berberine: AMPK-HIF-1α-P-gp inactivation played a crucial role on the DOX chemosensitivity of low-dose berberine, while AMPK-HIF-1α downregulaton inducing p53 activation led to apoptosis in high-dose berberine. These results were consistent to the transplanted mice model bearing MCF-7 drug-resistance tumor treated by berberine combined with DOX or high-dose berberine alone. This work shed light on a potentially therapeutic attempt to overcome drug-resistant breast cancer.

Targeting the Oxidative Stress Response System of Fungi with Redox-Potent Chemosensitizing Agents

PubMed Central

Kim, Jong H.; Chan, Kathleen L.; Faria, Natália C. G.; Martins, M. de L.; Campbell, Bruce C.

2012-01-01

The cellular antioxidant system is a target in the antifungal action of amphotericin B (AMB) and itraconazole (ITZ), in filamentous fungi. The sakAΔ mutant of Aspergillus fumigatus, a mitogen-activated protein kinase (MAPK) gene deletion mutant in the antioxidant system, was found to be more sensitive to AMB or ITZ than other A. fumigatus strains, a wild type and a mpkCΔ mutant (a MAPK gene deletion mutant in the polyalcohol sugar utilization system). Complete fungal kill (≥99.9%) by ITZ or AMB was also achieved by much lower dosages for the sakAΔ mutant than for the other strains. It appears msnA, an Aspergillus ortholog to Saccharomyces cerevisiae MSN2 (encoding a stress-responsive C2H2-type zinc-finger regulator) and sakA and/or mpkC (upstream MAPKs) are in the same stress response network under tert-butyl hydroperoxide (t-BuOOH)-, hydrogen peroxide (H2O2)- or AMB-triggered toxicity. Of note is that ITZ-sensitive yeast pathogens were also sensitive to t-BuOOH, showing a connection between ITZ sensitivity and antioxidant capacity of fungi. Enhanced antifungal activity of AMB or ITZ was achieved when these drugs were co-applied with redox-potent natural compounds, 2,3-dihydroxybenzaldehyde, thymol or salicylaldehyde, as chemosensitizing agents. We concluded that redox-potent compounds, which target the antioxidant system in fungi, possess a chemosensitizing capacity to enhance efficacy of conventional drugs. PMID:22438852

Connective tissue growth factor promotes temozolomide resistance in glioblastoma through TGF-β1-dependent activation of Smad/ERK signaling.

PubMed

Zeng, Huijun; Yang, Zhao; Xu, Ningbo; Liu, Boyang; Fu, Zhao; Lian, Changlin; Guo, Hongbo

2017-06-15

Limited benefits and clinical utility of temozolomide (TMZ) for glioblastoma (GB) are frequently compromised by the development of acquired drug resistance. Overcoming TMZ resistance and uncovering the underlying mechanisms are challenges faced during GB chemotherapy. In this study, we reported that connective tissue growth factor (CTGF) was associated with GB chemoresistance and significantly upregulated in TMZ-treated GB cells. CTGF knockdown promoted TMZ-induced cell apoptosis and enhanced chemosensitivity, whereas its overexpression markedly conferred TMZ resistance in vitro and in vivo. Moreover, CTGF promoted TMZ resistance through stem-like properties acquisition and CD44 interference reversed the CTGF-induced TMZ resistance. Mechanistically, further investigation revealed that the TMZ-induced CTGF upregulation was tissue growth factor (TGF-β) dependent, and regulated by TGF-β1 activation through Smad and ERK1/2 signaling. Together, our results suggest a pivotal role of CTGF-mediated TMZ resistance through TGF-β1-dependent activation of Smad/ERK signaling pathways. These data provide us insights for identifying potential targets that are beneficial for overcoming TMZ resistance in GB.

Proton pump inhibitors as anti vacuolar-ATPases drugs: a novel anticancer strategy.

PubMed

Spugnini, Enrico P; Citro, Gennaro; Fais, Stefano

2010-05-08

The vacuolar ATPases are ATP-dependent proton pumps whose functions include the acidification of intracellular compartments and the extrusion of protons through the cell cytoplasmic membrane. These pumps play a pivotal role in the regulation of cell pH in normal cells and, to a much greater extent, in tumor cells. In fact, the glucose metabolism in hypoxic conditions by the neoplasms leads to an intercellular pH drift towards acidity. The acid microenvironment is modulated through the over-expression of H+ transporters that are also involved in tumor progression, invasiveness, distant spread and chemoresistance. Several strategies to block/downmodulate the efficiency of these transporters are currently being investigated. Among them, proton pump inhibitors have shown to successfully block the H+ transporters in vitro and in vivo, leading to apoptotic death. Furthermore, their action seems to synergize with conventional chemotherapy protocols, leading to chemosensitization and reversal of chemoresistance. Aim of this article is to critically revise the current knowledge of this cellular machinery and to summarize the therapeutic strategies developed to counter this mechanism.

High-Affinity Binding of Silybin Derivatives to the Nucleotide-Binding Domain of a Leishmania tropica P-Glycoprotein-Like Transporter and Chemosensitization of a Multidrug-Resistant Parasite to Daunomycin

PubMed Central

Pérez-Victoria, José M.; Pérez-Victoria, F. Javier; Conseil, Gwenaëlle; Maitrejean, Mathias; Comte, Gilles; Barron, Denis; Di Pietro, Attilio; Castanys, Santiago; Gamarro, Francisco

2001-01-01

In order to overcome the multidrug resistance mediated by P-glycoprotein-like transporters in Leishmania spp., we have studied the effects produced by derivatives of the flavanolignan silybin and related compounds lacking the monolignol unit on (i) the affinity of binding to a recombinant C-terminal nucleotide-binding domain of the L. tropica P-glycoprotein-like transporter and (ii) the sensitization to daunomycin on promastigote forms of a multidrug-resistant L. tropica line overexpressing the transporter. Oxidation of the flavanonol silybin to the corresponding flavonol dehydrosilybin, the presence of the monolignol unit, and the addition of a hydrophobic substituent such as dimethylallyl, especially at position 8 of ring A, considerably increased the binding affinity. The in vitro binding affinity of these compounds for the recombinant cytosolic domain correlated with their modulation of drug resistance phenotype. In particular, 8-(3,3-dimethylallyl)-dehydrosilybin effectively sensitized multidrug-resistant Leishmania spp. to daunomycin. The cytosolic domains are therefore attractive targets for the rational design of inhibitors against P-glycoprotein-like transporters. PMID:11158738

miR-133b down-regulates ABCC1 and enhances the sensitivity of CRC to anti-tumor drugs.

PubMed

Chen, Miao; Li, Daojiang; Gong, Ni; Wu, Hao; Su, Chen; Xie, Canbin; Xiang, Hong; Lin, Changwei; Li, Xiaorong

2017-08-08

Multidrug resistance (MDR) is the main cause of failed chemotherapy treatments. Therefore, preventing MDR is pivotal in treating colorectal cancer (CRC). In a previous study miR-133b was shown to be a tumor suppressor. Additionally, in CRC cells transfected with miR-133b, ATP-binding cassette (ABC) subfamily C member 1(ABCC1) was shown to be significantly down regulated. Whether miR-133b also enhances the chemosensitivity of drugs used to treat CRC by targeting ABCC1 is still unclear. Here, we utilized flow cytometry and high-performance liquid chromatography (HPLC) analysis to identify the ability of miR-133b to reserve MDR in CRC. We then used a dual-luciferase reporter assay to validate that miR-133b targets ABCC1. Further in vivo experiments were designed to validate the method in which miR-133b reversed MDR in CRC cells. The results demonstrated that the level of miR-133b was down-regulated and the expression of ABCC1 was up-regulated in drug-resistant CRC cells compared to non-drug-resistant CRC cells. The restoration of miR-133b expression in CRC drug-resistant cells in vitro resulted in reduced IC50s to chemotherapeutic drugs, significantly induced G1 accumulation, inhibited growth and promoted necrosis in combination with either 5-fluorouracil (5-FU) or vincristine (VCR), and decreased the expression of ABCC1. The dual-luciferase assay demonstrated that miR-133b directly targets ABCC1. The combination of agomiRNA-133b with chemotherapeutic drugs in vivo inhibited tumor growth induced by CRC drug-resistant cells. A xenograft from the in vivo model resulted in up-regulated levels of miR-133b and down-regulated levels of ABCC1. Therefore, miR-133b enhances the chemosensitivity of CRC cells to anti-tumor drugs by directly down-regulating ABCC1. This discovery provides a therapeutic strategy in which miR-133b is used as a potential sensitizer for drug-resistant CRC.

A self-assembled polyjuglanin nanoparticle loaded with doxorubicin and anti-Kras siRNA for attenuating multidrug resistance in human lung cancer.

PubMed

Wen, Zhong-Mei; Jie, Jing; Zhang, Yuan; Liu, Han; Peng, Li-Ping

2017-12-02

Lung cancer is a leading cause of cancer-associated mortality worldwide, which has a low survival rate. Multidrug resistance (MDR) is a major obstacle that hinders the treatment of lung cancer. Doxorubicin (DOX) is an anthracycline glycoside antibiotic, having a broad spectrum of anticancer activity against various solid tumors. Juglanin is a natural production, mainly extracted from green walnut husks of Juglans mandshurica, exhibiting various bioactivities. Here, we demonstrated that the combination of drug, gene and nanoparticle overcame MDR, inhibiting lung cancer progression. A novel nanoparticular pre-chemosensitizer was applied to develop a self-assembled nanoparticle formula of amphiphilic poly(juglanin (Jug) dithiodipropionic acid (DA))-b-poly(ethylene glycol) (PEG)-siRNA Kras with DOX in the core (DOX/PJAD-PEG-siRNA). The formed nanoparticles, appeared spherical shape, had mean particle size of 81.8 nm, and the zeta potential was -18.62 mV. The in vitro drug release results suggested that a sustained release was observed in DOX/PJAD-PEG-siRNA nanoparticles compared to the free DOX. Jug could improve the cytotoxicity of DOX to cancer cells with MDR. Oncogene, Kras, was dose-dependently reduced by treatment of DOX/PJAD-PEG-siRNA nanoparticles. Additionally, P-glycoprotein (MDR1) and c-Myc, contributing to tumor progression, were suppressed by the nanoparticles, while p53 was improved in drug-resistant cells. Colony formation analysis suggested that DOX/PJAD-PEG-siRNA nanoparticles showed the most effective role in reducing cancer cell proliferation. In vivo, DOX/PJAD-PEG-siRNA nanoparticles reduced tumor growth compared to the free DOX, accompanied with reduced KI-67 and enhanced TUNEL positive levels in drug-resistant xenografted nude mice. Thus, the findings above indicated that juglanin, as a chemosensitizer, potentiate the anti-cancer role of DOX in drug-resistant cancer cells. And the nanoparticles exhibited stronger antitumor efficiency, suggesting potential value in the treatment of lung cancer. Copyright © 2017. Published by Elsevier Inc.

Apigenin sensitizes BEL-7402/ADM cells to doxorubicin through inhibiting miR-101/Nrf2 pathway

PubMed Central

Gao, Ai-Mei; Zhang, Xiao-Yu; Ke, Zun-Ping

2017-01-01

Chemo-resistance is one of the main obstacle in hepatocellular carcinoma therapy. Apigenin as a natural bioflavonoid has been exhibited anti-cancer properties in various malignant cancers. The aim of this study is to evaluate the potential chemo-sensitization effect of apigenin in doxorubicin-resistant hepatocellular carcinoma cell line BEL-7402/ADM and to investigate its possible mechanism. We found that apigenin significantly reversed doxorubicin sensitivity and induced caspase-dependent apoptosis in BEL-7402/ADM cells. Furthermore, apigenin induced miR-101 expression, and overexpression of miR-101 mimicked the doxorubicin-sensitizing effect of apigenin. Importantly, we showed that miR-101 was able to target the 3′-UTR of Nrf2. The results suggested that apigenin sensitizes BEL-7402/ADM cells to doxorubicin through miR-101/Nrf2 pathway, which furtherly supports apigenin as a potential chemo-sensitizer for hepatocellular carcinoma. PMID:29137246

The progestin etonogestrel enhances the respiratory response to metabolic acidosis in newborn rats. Evidence for a mechanism involving supramedullary structures.

PubMed

Loiseau, Camille; Osinski, Diane; Joubert, Fanny; Straus, Christian; Similowski, Thomas; Bodineau, Laurence

2014-05-01

Central congenital hypoventilation syndrome is a neuro-respiratory disease characterized by the dysfunction of the CO2/H(+) chemosensitive neurons of the retrotrapezoid nucleus/parafacial respiratory group. A recovery of CO2/H(+) chemosensitivity has been observed in some central congenital hypoventilation syndrome patients coincidental with contraceptive treatment by a potent progestin, desogestrel (Straus et al., 2010). The mechanisms of this progestin effect remain unknown, although structures of medulla oblongata, midbrain or diencephalon are known to be targets for progesterone. In the present study, on ex vivo preparations of central nervous system of newborn rats, we show that acute exposure to etonogestrel (active metabolite of desogestrel) enhanced the increased respiratory frequency induced by metabolic acidosis via a mechanism involving supramedullary structures located in pontine, mesencephalic or diencephalic regions. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

miR-1182 inhibits growth and mediates the chemosensitivity of bladder cancer by targeting hTERT

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

Zhou, Jun; Dai, Wenbin, E-mail: daiwenbin271@163.com; Song, Jianming

2016-02-05

microRNAs (miRNAs) have been demonstrated to contribute to tumor progression and metastasis and proposed to be key regulators of diverse biological processes. In this study, we report that miR-1182 is deregulated in bladder cancer tissues and cell lines. To characterize the role of miR-1182 in bladder cancer cells, we performed functional assays. The overexpression of miR-1182 significantly inhibits bladder cancer cell proliferation, colony formation, and invasion. Moreover, its up-regulation induced cell cycle arrest and apoptosis and mediated chemosensitivity to cisplatin in bladder cancer. Furthermore, a luciferase reporter assay and a rescue experiment indicated that miR-1182 directly targets hTERT by bindingmore » its 3′UTR. In conclusion, these results demonstrate that miR-1182 acts as a tumor suppressor and may be a potential biomarker for bladder cancer diagnosis and treatment.« less

Heterogeneity in cancer cells: variation in drug response in different primary and secondary colorectal cancer cell lines in vitro.

PubMed

Arul, Melanie; Roslani, April Camilla; Cheah, Swee Hung

2017-05-01

Tumor heterogeneity may give rise to differential responses to chemotherapy drugs. Therefore, unraveling tumor heterogeneity has an implication for biomarker discovery and cancer therapeutics. To test this phenomenon, we investigated the differential responses of three secondary colorectal cancer cell lines of different origins (HCT116, HT29, and SW620 cells) and four novel primary cell lines obtained from different colorectal cancer patients to 5-fluorouracil (5-FU) and oxaliplatin (L-OHP) and explored the differences in gene expression among the primary cell lines in response to exposure to cytotoxic drugs. Cells were exposed to different doses of 5-FU and L-OHP separately or in combinations of equitoxic drug or equimolar drug ratios (median effect of Chou-Talalay principle). Cell viability was assessed using MTT assay and the respective IC 50 values were determined. Changes in gene expression in primary cell lines after exposure to the same drug doses were compared using real-time PCR array. The sensitivities (IC 50 ) of different cell lines, both secondary and primary, to 5-FU and L-OHP were significantly different, whether in monotherapy or combined treatment. Primary cell lines needed higher doses to reach IC 50 . There were variations in gene expression among the primary cell lines of different chemosensitivities to the challenge of the same combined dose of 5-FU and L-OHP. The results confirm the heterogeneous nature of colorectal cancer cells from different patient tumors. Studies using primary cancer cells established from patient's tumors rather than secondary cell lines will more closely reflect the actual character of the disease.

Comparative Study of Different Nano-Formulations of Curcumin for Reversal of Doxorubicin Resistance in K562R Cells.

PubMed

Dash, Tapan K; Konkimalla, V Badireenath

2017-02-01

Curcumin is very well established as a chemo-therapeutic, chemo-preventive and chemo-sensitizing agent in diverse disease conditions. As the isolated pure form has poor solubility and pharmacokinetic problems, therefore it is encapsulated in to several nano-formulations to improve its bioavailability. Here in the current study, we aim to compare different nano-formulations of curcumin for their chemo-sensitizing activity in doxorubicin (DOX) resistant K562 cells. Four different curcumin formulations were prepared namely DMSO assisted curcumin nano-dispersion (CurD, 260 nm), liposomal curcumin (CurL, 165 nm), MPEG-PCL micellar curcumin (CurM, 18 nm) and cyclodextrin encapsulated curcumin (CurN, 37 nm). The formulations were subjected to particle characterizations (size, zeta potential, release studies), followed by biological assays such as cellular uptake, P-gp inhibitory activity and reversal of DOX resistance by co-treatment with DOX. Curcumin uptake in K562N and K562R cells was mildly reduced when treated with CurL and CurM, while for CurD and CurN the uptake remained equivalent. However, CurL retained P-gp inhibitory activity of curcumin and with a considerable chemo-sensitizing effect but CurM showed no P-gp inhibitory activity. CurN retained above biological activities, but requires a secondary carrier under in vivo conditions. From the results, CurM was found to be most suitable for solubilization of curcumin where as CurL can be considered as most suitable nano-formulation for reversal of DOX resistance.

IMMUNOCYTOCHEMICAL IDENTIFICATION OF ELECTRONEUTRAL NA+-COUPLED HCO3− TRANSPORTERS IN FRESHLY DISSOCIATED MOUSE MEDULLARY RAPHÉ NEURONS

PubMed Central

COLEY, A. A.; RUFFIN, V. A.; MOSS, F. J.; HOPFER, U.; BORON, W. F.

2013-01-01

The medullary raphé (MR) of the medulla oblongata contains chemosensitive neurons that respond to increases in arterial [CO2], by altering firing rate, with increases being associated with serotonergic (5-hydroxytryptamine [5HT]) neurons and decreases, with GABAergic neurons. Both types of neurons contribute to increased alveolar ventilation. Decreases in intracellular pH are thought to link the rise in [CO2] to increased ventilation. Because electroneutral Na+-coupled HCO3− transporters (nNCBTs), which help protect cells from intracellular acidosis, are expressed robustly in the neurons of the central nervous system, a key question is whether these transporters are present in chemosensitive neurons. Therefore, we used an immunocytochemistry approach to identify neurons (using a microtubule associated protein-2 monoclonal antibody) and specifically 5HT neurons (TPH monoclonal antibody) or GABAergic neurons (GAD2 monoclonal antibody) in freshly dissociated cells from the mouse MR. We also co-labeled with polyclonal antibodies against the three nNCBTs: NBCn1, NDCBE, and NBCn2. We exploited ePet-EYFP (enhanced yellow fluorescent protein) mice (with EYFP-labeled 5HT neurons) as well as mice genetically deficient in each of the three nNCBTs. Quantitative image analysis distinguished positively stained cells from background signals. We found that >80% of GAD2+ cells also were positive for NDCBE, and >90% of the TPH+ and GAD2+ cells were positive for the other nNCBTs. Assuming that the transporters are independently distributed among neurons, we can conclude that virtually all chemosensitive MR neurons contain at least one nNCBT. PMID:23500099

Outcomes in relapsed Hodgkin's lymphoma treated with autologous and allogeneic hematopoietic cell transplantation at the Pontificia Universidad Católica de Chile

PubMed Central

Ramirez, Pablo; Ocqueteau, Mauricio; Rodriguez, Alejandra; Garcia, Maria Jose; Sarmiento, Mauricio; Ernst, Daniel; Jara, Veronica; Bertin, Pablo

2015-01-01

Introduction Hodgkin's lymphoma is a highly curable disease. Autologous and reduced intensity allogeneic hematopoietic cell transplantations are alternatives to treat relapsed patients. Here, we report on the results of one service using these procedures. Methods All patients who underwent transplantations in our institution between 1996 and 2014 were retrospectively studied and demographics, toxicities and survival rate were analyzed. Results This study evaluated 24 autologous and five reduced intensity allogeneic transplantations: the median ages of the patients were 29 and 32 years, respectively. At the time of autologous transplantation, ten patients were in complete remission, nine had chemosensitive disease but were not in complete remission, three had refractory disease and the status of two is unknown. In the allogeneic group, two were in complete remission and three had chemosensitive disease. The 5-year overall survival after autologous transplantation was 42% (66% patients were in complete remission, 37% had chemosensitive disease with incomplete remission and 0% had refractory disease) and 1-year overall survival after allogeneic transplantation was 80%. Transplant-related mortality was 0% in patients conditioned with the ifosfamide/carboplatin/etoposide (ICE), carmustine/etoposide/cyclophosphamide (BEC) and carmustine/etoposide/cytarabine/melphalan (BEAM) regimens, 37% in patients conditioned with busulfan-based regimens and 20% in allogeneic transplantations. Conclusions Hematopoietic cell transplantation for relapsed Hodgkin's lymphoma is a potentially curative procedure especially in patients in complete remission at the time of autologous transplantations, and possibly after allogeneic transplantations. Further studies are necessary to clarify the role of allogeneic transplantations in the treatment of relapsed Hodgkin's lymphoma. PMID:26041421

Cinnamic Acid Analogs as Intervention Catalysts for Overcoming Antifungal Tolerance.

PubMed

Kim, Jong H; Chan, Kathleen L; Cheng, Luisa W

2017-10-21

Disruption of fungal cell wall should be an effective intervention strategy. However, the cell wall-disrupting echinocandin drugs, such as caspofungin (CAS), cannot exterminate filamentous fungal pathogens during treatment. For potency improvement of cell wall-disrupting agents (CAS, octyl gallate (OG)), antifungal efficacy of thirty-three cinnamic acid derivatives was investigated against Saccharomyces cerevisiae slt2 Δ, bck1 Δ, mutants of the mitogen-activated protein kinase (MAPK), and MAPK kinase kinase, respectively, in cell wall integrity system, and glr1 Δ, mutant of CAS-responsive glutathione reductase. Cell wall mutants were highly susceptible to four cinnamic acids (4-chloro-α-methyl-, 4-methoxy-, 4-methyl-, 3-methylcinnamic acids), where 4-chloro-α-methyl- and 4-methylcinnamic acids possessed the highest activity. Structure-activity relationship revealed that 4-methylcinnamic acid, the deoxygenated structure of 4-methoxycinnamic acid, overcame tolerance of glr1 Δ to 4-methoxycinnamic acid, indicating the significance of para substitution of methyl moiety for effective fungal control. The potential of compounds as chemosensitizers (intervention catalysts) to cell wall disruptants (viz., 4-chloro-α-methyl- or 4-methylcinnamic acids + CAS or OG) was assessed according to Clinical Laboratory Standards Institute M38-A. Synergistic chemosensitization greatly lowers minimum inhibitory concentrations of the co-administered drug/agents. 4-Chloro-α-methylcinnamic acid further overcame fludioxonil tolerance of Aspergillus fumigatus antioxidant MAPK mutants ( sakA Δ, mpkC Δ). Collectively, 4-chloro-α-methyl- and 4-methylcinnamic acids possess chemosensitizing capability to augment antifungal efficacy of conventional drug/agents, thus could be developed as target-based (i.e., cell wall disruption) intervention catalysts.

Fatty acid synthase regulates the chemosensitivity of breast cancer cells to cisplatin-induced apoptosis.

PubMed

Al-Bahlani, Shadia; Al-Lawati, Hanaa; Al-Adawi, Moza; Al-Abri, Nadia; Al-Dhahli, Buthaina; Al-Adawi, Kawther

2017-06-01

Fatty acid synthase (FASN) is a key enzyme in fat biosynthesis that is over-expressed in advanced breast cancer stages. Cisplatin (CDDP) is a platinum-based drug used in the treatment of certain types of this disease. Although it was shown that FASN inhibition induced apoptosis by enhancing the cytotoxicity of certain drugs in breast cancer, its role in regulating the chemosensitivity of different types of breast cancer cells to CDDP-induced apoptosis is not established yet. Therefore, two different breast cancer cell lines; triple negative breast cancer (TNBC; MDA-MB-231) and triple positive breast cancer (TPBC; BT-474) cells were used to examine such role. We show that TNBC cells had naturally less fat content than TPBC cells. Subsequently, the fat content increased in both cells when treated with Palmitate rather than Oleate, whereas both fatty acids produced apoptotic ultra-structural effects and attenuated FASN expression. However, Oleate increased FASN expression in TPBC cells. CDDP decreased FASN expression and increased apoptosis in TNBC cells. These effects were further enhanced by combining CDDP with fatty acids. We also illustrate that the inhibition of FASN by either siRNA or exogenous inhibitor decreased CDDP-induced apoptosis in TPBC cells suggesting its role as an apoptotic factor, while an opposite finding was observed in TNBC cells when siRNA and fatty acids were used, suggesting its role as a survival factor. To our knowledge, we are the first to demonstrate a dual role of FASN in CDDP-induced apoptosis in breast cancer cells and how it can modulate their chemosensitivity.

Gene expression patterns in formalin-fixed, paraffin-embedded core biopsies predict docetaxel chemosensitivity in breast cancer patients.

PubMed

Chang, Jenny C; Makris, Andreas; Gutierrez, M Carolina; Hilsenbeck, Susan G; Hackett, James R; Jeong, Jennie; Liu, Mei-Lan; Baker, Joffre; Clark-Langone, Kim; Baehner, Frederick L; Sexton, Krsytal; Mohsin, Syed; Gray, Tara; Alvarez, Laura; Chamness, Gary C; Osborne, C Kent; Shak, Steven

2008-03-01

Previously, we had identified gene expression patterns that predicted response to neoadjuvant docetaxel. Other studies have validated that a high Recurrence Score (RS) by the 21-gene RT-PCR assay is predictive of worse prognosis but better response to chemotherapy. We investigated whether tumor expression of these 21 genes and other candidate genes can predict response to docetaxel. Core biopsies from 97 patients were obtained before treatment with neoadjuvant docetaxel (4 cycles, 100 mg/m2 q3 weeks). Three 10-microm FFPE sections were submitted for quantitative RT-PCR assays of 192 genes that were selected from our previous work and the literature. Of the 97 patients, 81 (84%) had sufficient invasive cancer, 80 (82%) had sufficient RNA for QRTPCR assay, and 72 (74%) had clinical response data. Mean age was 48.5 years, and the median tumor size was 6 cm. Clinical complete responses (CR) were observed in 12 (17%), partial responses in 41 (57%), stable disease in 17 (24%), and progressive disease in 2 patients (3%). A significant relationship (P<0.05) between gene expression and CR was observed for 14 genes, including CYBA. CR was associated with lower expression of the ER gene group and higher expression of the proliferation gene group from the 21 gene assay. Of note, CR was more likely with a high RS (P=0.008). We have established molecular profiles of sensitivity to docetaxel. RT-PCR technology provides a potential platform for a predictive test of docetaxel chemosensitivity using small amounts of routinely processed material.

Acridine-intercalator based hypoxia selective cytotoxins

DOEpatents

Papadopoulou-Rosenzweig, Maria; Bloomer, William D.; Bloomer, William D.

1994-01-01

Hypoxia selective cytotoxins of the general formula ##STR1## wherein n is from 1 to 5, and NO.sub.2 is in at least one of the 2, 4 or 5-positions of the imidazole. Such compounds have utility as radiosensitizers and chemosensitizers.

Restoration of microRNA‑218 increases cellular chemosensitivity to cervical cancer by inhibiting cell‑cycle progression.

PubMed

Dong, Ruofan; Qiu, Haifeng; Du, Guiqiang; Wang, Yuan; Yu, Jinjin; Mao, Caiping

2014-12-01

We previously reported frequent loss of microRNA‑218 (miR‑218) in human cervical cancer, which was associated with tumor progression and poor prognosis. In this study, we investigated whether restoration of the miR‑218 level is a valid strategy for the treatment of cervical cancer. The expression of miR‑218 in cervical cancer samples and cell lines was quantified by reverse transcription TaqMan quantitative (RT‑q)PCR. Overexpression of miR‑218 was achieved by both transient and stable transfection, using a miR‑218 mimic and a miR‑218‑expressing plasmid, respectively. Alterations in cellular proliferation and cell‑cycle progression were measured by the MTT assay and flow cytometry analysis. Nude mice bearing SiHa xenografts were used to investigate the functions of miR‑218 and carboplatin on tumor growth and weight. The expression of cycle‑related proteins was detected by western blotting and immunohistochemical staining. In vitro, miR‑218 significantly inhibited cellular growth in all four cell lines tested (P=0.021 for CaSki, P=0.009 for HeLa, P=0.016 for SiHa, and P=0.029 for C33A). Overexpression of miR‑218 induced G1 phase arrest and reduced expression of cyclin D1 and CDK4. In vivo, restoration of miR‑218 notably inhibited tumor growth and decreased tumor weight. In primary cultured samples, tumors with high levels of miR‑218 were more sensitive to carboplatin (R2=0.3319, P=0.0026); consistently, miR‑218 overexpression suppressed tumor growth, induced cell‑cycle arrest, and reduced the cyclin D1 level. Based on these and previous results, we conclude that restoration of the miR‑218 level inhibits the growth of cervical cancer cells both in vitro and in vivo; furthermore, overexpression of miR‑218 sensitizes cervical cancer cells to carboplatin. Our findings suggest a novel therapy for cervical cancer based on miR‑218, especially in patients with reduced levels of miR‑218.

Prospective correlative chemosensitivity testing in high-dose intraarterial chemotherapy for liver metastases.

PubMed

Link, K H; Aigner, K R; Kuehn, W; Schwemmle, K; Kern, D H

1986-09-01

Clinical response of liver metastases treated by high-dose intraarterial chemotherapy (HDIAC) delivered via the hepatic artery was predicted by a modification of the human tumor colony-forming assay (HTCFA) originally described by Hamburger and Salmon [Science (Wash. DC), 197:461-463, 1977. In a first set of experiments, the immediate clinical response to HDIAC was determined in 12 patients with colorectal liver metastases. Biopsies were taken immediately before and after HDIAC, and cells were plated in the HTCFA. Three patients received intraoperative 4-epidoxorubicin and another 9 received mitomycin C by 15-min intraarterial infusions. Sensitivity in the HTCFA was defined as 50% inhibition of colony formation in tumors exposed to the chemotherapeutic agent, compared to the untreated controls. Clinical response was accurately predicted by the HTCFA in 11 of 12 cases. Eight patients had a regression of disease following HDIAC treatment with mitomycin C, as evidenced by either greater than 50% reduction in carcinoembryonic antigen serum level (7 patients) or regression of tumor by computed tomography scan (1 patient). Three patients had no evidence of clinical response to epidoxorubicin, and their tumors were resistant to epidoxorubicin in the HTCFA. One tumor was sensitive to mitomycin C in the HTCFA, but serum carcinoembryonic antigen in the patient continued to increase following HDIAC. The HTCFA was also performed on untreated biopsies following incubation in vitro with the drug used for HDIAC. Results correlated with clinical response in all 12 cases. In a second set of experiments, the HTCFA was used to predict the long-term clinical response to HDIAC of 30 patients with liver metastases. One patient had breast cancer metastases, one patient had carcinoid liver metastases, 4 had liver metastases of malignant melanoma, and 24 patients had colorectal liver metastases. All 21 of the patients whose tumors were sensitive in vitro had clinical response, while 6 of 9 patients predicted by the HTCFA to be resistant had no clinical response. Our results demonstrate a high correlation between the HTCFA and clinical response.

Use of benzo anologs to enhance antimycotic activity of kresoxim methyl for control of aflatoxigenic fungal pathogens

USDA-ARS?s Scientific Manuscript database

Potentiation of the conventional fungicide, strobilurin, was achieved by octylgallate-mediated chemosensitization. Octylgallate exhibited considerably higher antifungal activity compared to veratraldehyde. Octylgallate in concert with the fungicide, strobilurin (kresoxim methyl), greatly enhanced se...

Curcumin Chemosensitizes 5-Fluorouracil Resistant MMR-Deficient Human Colon Cancer Cells in High Density Cultures

PubMed Central

Shakibaei, Mehdi; Buhrmann, Constanze; Kraehe, Patricia; Shayan, Parviz; Lueders, Cora; Goel, Ajay

2014-01-01

Objective Treatment of colorectal cancer (CRC) remains a clinical challenge, as more than 15% of patients are resistant to 5-Fluorouracil (5-FU)-based chemotherapeutic regimens, and tumor recurrence rates can be as high as 50–60%. Cancer stem cells (CSC) are capable of surviving conventional chemotherapies that permits regeneration of original tumors. Therefore, we investigated the effectiveness of 5-FU and plant polyphenol (curcumin) in context of DNA mismatch repair (MMR) status and CSC activity in 3D cultures of CRC cells. Methods High density 3D cultures of CRC cell lines HCT116, HCT116+ch3 (complemented with chromosome 3) and their corresponding isogenic 5-FU-chemo-resistant derivative clones (HCT116R, HCT116+ch3R) were treated with 5-FU either without or with curcumin in time- and dose-dependent assays. Results Pre-treatment with curcumin significantly enhanced the effect of 5-FU on HCT116R and HCR116+ch3R cells, in contrast to 5-FU alone as evidenced by increased disintegration of colonospheres, enhanced apoptosis and by inhibiting their growth. Curcumin and/or 5-FU strongly affected MMR-deficient CRC cells in high density cultures, however MMR-proficient CRC cells were more sensitive. These effects of curcumin in enhancing chemosensitivity to 5-FU were further supported by its ability to effectively suppress CSC pools as evidenced by decreased number of CSC marker positive cells, highlighting the suitability of this 3D culture model for evaluating CSC marker expression in a close to vivo setting. Conclusion Our results illustrate novel and previously unrecognized effects of curcumin in enhancing chemosensitization to 5-FU-based chemotherapy on DNA MMR-deficient and their chemo-resistant counterparts by targeting the CSC sub-population. (246 words in abstract). PMID:24404205

Curcumin chemosensitizes 5-fluorouracil resistant MMR-deficient human colon cancer cells in high density cultures.

PubMed

Shakibaei, Mehdi; Buhrmann, Constanze; Kraehe, Patricia; Shayan, Parviz; Lueders, Cora; Goel, Ajay

2014-01-01

Treatment of colorectal cancer (CRC) remains a clinical challenge, as more than 15% of patients are resistant to 5-Fluorouracil (5-FU)-based chemotherapeutic regimens, and tumor recurrence rates can be as high as 50-60%. Cancer stem cells (CSC) are capable of surviving conventional chemotherapies that permits regeneration of original tumors. Therefore, we investigated the effectiveness of 5-FU and plant polyphenol (curcumin) in context of DNA mismatch repair (MMR) status and CSC activity in 3D cultures of CRC cells. High density 3D cultures of CRC cell lines HCT116, HCT116+ch3 (complemented with chromosome 3) and their corresponding isogenic 5-FU-chemo-resistant derivative clones (HCT116R, HCT116+ch3R) were treated with 5-FU either without or with curcumin in time- and dose-dependent assays. Pre-treatment with curcumin significantly enhanced the effect of 5-FU on HCT116R and HCR116+ch3R cells, in contrast to 5-FU alone as evidenced by increased disintegration of colonospheres, enhanced apoptosis and by inhibiting their growth. Curcumin and/or 5-FU strongly affected MMR-deficient CRC cells in high density cultures, however MMR-proficient CRC cells were more sensitive. These effects of curcumin in enhancing chemosensitivity to 5-FU were further supported by its ability to effectively suppress CSC pools as evidenced by decreased number of CSC marker positive cells, highlighting the suitability of this 3D culture model for evaluating CSC marker expression in a close to vivo setting. Our results illustrate novel and previously unrecognized effects of curcumin in enhancing chemosensitization to 5-FU-based chemotherapy on DNA MMR-deficient and their chemo-resistant counterparts by targeting the CSC sub-population. (246 words in abstract).

Association of a cytarabine chemosensitivity related gene expression signature with survival in cytogenetically normal acute myeloid leukemia.

PubMed

Yan, Han; Wen, Lu; Tan, Dan; Xie, Pan; Pang, Feng-Mei; Zhou, Hong-Hao; Zhang, Wei; Liu, Zhao-Qian; Tang, Jie; Li, Xi; Chen, Xiao-Ping

2017-01-03

The prognosis of cytogenetically normal acute myeloid leukemia (CN-AML) varies greatly among patients. Achievement of complete remission (CR) after chemotherapy is indispensable for a better prognosis. To develop a gene signature predicting overall survival (OS) in CN-AML, we performed data mining procedure based on whole genome expression data of both blood cancer cell lines and AML patients from open access database. A gene expression signature including 42 probes was derived. These probes were significantly associated with both cytarabine half maximal inhibitory concentration values in blood cancer cell lines and OS in CN-AML patients. By using cox regression analysis and linear regression analysis, a chemo-sensitive score calculated algorithm based on mRNA expression levels of the 42 probes was established. The scores were associated with OS in both the training sample (p=5.13 × 10-4, HR=2.040, 95% CI: 1.364-3.051) and the validation sample (p=0.002, HR=2.528, 95% CI: 1.393-4.591) of the GSE12417 dataset from Gene Expression Omnibus. In The Cancer Genome Atlas (TCGA) CN-AML patients, higher scores were found to be associated with both worse OS (p=0.013, HR=2.442, 95% CI: 1.205-4.950) and DFS (p=0.015, HR=2.376, 95% CI: 1.181-4.779). Results of gene ontology (GO) analysis showed that all the significant GO Terms were correlated with cellular component of mitochondrion. In summary, a novel gene set that could predict prognosis of CN-AML was identified presently, which provided a new way to identify genes impacting AML chemo-sensitivity and prognosis.

Association of a cytarabine chemosensitivity related gene expression signature with survival in cytogenetically normal acute myeloid leukemia

PubMed Central

Yan, Han; Wen, Lu; Tan, Dan; Xie, Pan; Pang, Feng-mei; Zhou, Hong-hao; Zhang, Wei; Liu, Zhao-qian; Tang, Jie; Li, Xi; Chen, Xiao-ping

2017-01-01

The prognosis of cytogenetically normal acute myeloid leukemia (CN-AML) varies greatly among patients. Achievement of complete remission (CR) after chemotherapy is indispensable for a better prognosis. To develop a gene signature predicting overall survival (OS) in CN-AML, we performed data mining procedure based on whole genome expression data of both blood cancer cell lines and AML patients from open access database. A gene expression signature including 42 probes was derived. These probes were significantly associated with both cytarabine half maximal inhibitory concentration values in blood cancer cell lines and OS in CN-AML patients. By using cox regression analysis and linear regression analysis, a chemo-sensitive score calculated algorithm based on mRNA expression levels of the 42 probes was established. The scores were associated with OS in both the training sample (p=5.13 × 10−4, HR=2.040, 95% CI: 1.364-3.051) and the validation sample (p=0.002, HR=2.528, 95% CI: 1.393-4.591) of the GSE12417 dataset from Gene Expression Omnibus. In The Cancer Genome Atlas (TCGA) CN-AML patients, higher scores were found to be associated with both worse OS (p=0.013, HR=2.442, 95% CI: 1.205-4.950) and DFS (p=0.015, HR=2.376, 95% CI: 1.181-4.779). Results of gene ontology (GO) analysis showed that all the significant GO Terms were correlated with cellular component of mitochondrion. In summary, a novel gene set that could predict prognosis of CN-AML was identified presently, which provided a new way to identify genes impacting AML chemo-sensitivity and prognosis. PMID:27903973

Elucidation of chemosensitization effect of acridones in cancer cell lines: Combined pharmacophore modeling, 3D QSAR, and molecular dynamics studies.

PubMed

Gade, Deepak Reddy; Makkapati, Amareswararao; Yarlagadda, Rajesh Babu; Peters, Godefridus J; Sastry, B S; Rajendra Prasad, V V S

2018-06-01

Overexpression of P-glycoprotein (P-gp) leads to the emergence of multidrug resistance (MDR) in cancer treatment. Acridones have the potential to reverse MDR and sensitize cells. In the present study, we aimed to elucidate the chemosensitization potential of acridones by employing various molecular modelling techniques. Pharmacophore modeling was performed for the dataset of chemosensitizing acridones earlier proved for cytotoxic activity against MCF7 breast cancer cell line. Gaussian-based QSAR studies also performed to predict the favored and disfavored region of the acridone molecules. Molecular dynamics simulations were performed for compound 10 and human P-glycoprotein (obtained from Homology modeling). An efficient pharmacophore containing 2 hydrogen bond acceptors and 3 aromatic rings (AARRR.14) was identified. NCI 2012 chemical database was screened against AARRR.14 CPH and identified 25 best-fit molecules. Potential regions of the compound were identified through Field (Gaussian) based QSAR. Regression analysis of atom-based QSAR resulted in r 2 of 0.95 and q 2 of 0.72, whereas, regression analysis of field-based QSAR resulted in r 2 of 0.92 and q 2 of 0.87 along with r 2 cv as 0.71. The fate of the acridone molecule (compound 10) in the P-glycoprotein environment is analyzed through analyzing the conformational changes occurring during the molecular dynamics simulations. Combined data of different in silico techniques provided basis for deeper understanding of structural and mechanistic insights of interaction phenomenon of acridones with P-glycoprotein and also as strategic basis for designing more potent molecules for anti-cancer and multidrug resistance reversal activities. Copyright © 2018 Elsevier Ltd. All rights reserved.

The effect of consistent practice of yogic breathing exercises on the human cardiorespiratory system.

PubMed

McKay, Joshua A A; McCulloch, Cara L; Querido, Jordan S; Foster, Glen E; Koehle, Michael S; Sheel, A William

2016-11-01

The purpose of this investigation was to quantify the cardiovascular, respiratory, and cerebrovascular effects of two common yogic breathing exercises (YBE): bhastrika and chaturbhuj; and to determine the effect of their consistent practice on chemosensitivity. The first study was cross-sectional and compared experienced yogic breathers (YB) with matched controls; whereas the second was a 10-week longitudinal training study. The results support four major findings. First chaturbhuj resulted in a hypoxic stimulus in experienced YB compared to control [end-tidal oxygen tension (P ET O 2 ), YB: 77.5±5.7mmHg, P<0.05; control: 94.3±12.0mmHg]. Second, performance of chaturbhuj resulted in cyclic oscillations of mean arterial pressure (MAP), heart rate (HR), and middle cerebral artery velocity (MCAv) consistent with the phases of respiration. Third, post training, performance of bhastrika reduced P ET O 2 (end breath-hold: 90.8 8±12.1mmHg) compared to rest (100.1±7.4, P<0.05); it also resulted in significantly increased MAP at end breath-hold (96.7±13.0mmHg) compared to rest (83.0±6.6mmHg, P<0.05) and significantly increased mean MCAv (end breath-hold: 87.4±23.0cm/s, P<0.05; rest: 55.8±26.3cm/s). Fourth, experienced YB had lower central chemosensitivity than controls (YB: 3.4±0.4; control: 4.6±1.2L/min/mmHg; P<0.05). In conclusion, YBE significantly alter end-tidal gases, resulting in complex oscillations of cardiovascular and cerebrovascular variables, and if practiced consistently, may reduce chemosensitivity. Copyright © 2016. Published by Elsevier B.V.

Omega 3 fatty acids chemosensitize multidrug resistant colon cancer cells by down-regulating cholesterol synthesis and altering detergent resistant membranes composition

PubMed Central

2013-01-01

Background The activity of P-glycoprotein (Pgp) and multidrug resistance related protein 1 (MRP1), two membrane transporters involved in multidrug resistance of colon cancer, is increased by high amounts of cholesterol in plasma membrane and detergent resistant membranes (DRMs). It has never been investigated whether omega 3 polyunsatured fatty acids (PUFAs), which modulate cholesterol homeostasis in dyslipidemic syndromes and have chemopreventive effects in colon cancer, may affect the response to chemotherapy in multidrug resistant (MDR) tumors. Methods We studied the effect of omega 3 PUFAs docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) in human chemosensitive colon cancer HT29 cells and in their MDR counterpart, HT29-dx cells. Results MDR cells, which overexpressed Pgp and MRP1, had a dysregulated cholesterol metabolism, due to the lower expression of ubiquitin E3 ligase Trc8: this produced lower ubiquitination rate of 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCoAR), higher cholesterol synthesis, higher cholesterol content in MDR cells. We found that DHA and EPA re-activated Trc8 E3 ligase in MDR cells, restored the ubiquitination rate of HMGCoAR to levels comparable with chemosensitive cells, reduced the cholesterol synthesis and incorporation in DRMs. Omega 3 PUFAs were incorporated in whole lipids as well as in DRMs of MDR cells, and altered the lipid composition of these compartments. They reduced the amount of Pgp and MRP1 contained in DRMs, decreased the transporters activity, restored the antitumor effects of different chemotherapeutic drugs, restored a proper tumor-immune system recognition in response to chemotherapy in MDR cells. Conclusions Our work describes a new biochemical effect of omega 3 PUFAs, which can be useful to overcome chemoresistance in MDR colon cancer cells. PMID:24225025

Multiparametric Profiling for Identification of Chemosensitizers against Gram-Negative Bacteria

PubMed Central

Lôme, Vincent; Brunel, Jean-Michel; Pagès, Jean-Marie; Bolla, Jean-Michel

2018-01-01

Antibiotic resistance is now a worldwide therapeutic problem. Since the beginning of anti-infectious treatment bacteria have rapidly shown an incredible ability to develop and transfer resistance mechanisms. In the last decades, the design variation of pioneer bioactive molecules has strongly improved their activity and the pharmaceutical companies partly won the race against the clock. Since the 1980s, the new classes of antibiotics that emerged were mainly directed to Gram-positive bacteria. Thus, we are now facing to multidrug-resistant Gram-negative bacteria, with no therapeutic options to deal with them. These bacteria are mainly resistant because of their double membrane that conjointly impairs antibiotic accumulation and extrudes these molecules when entered. The main challenge is to allow antibiotics to cross the impermeable envelope and reach their targets. One promising solution would be to associate, in a combination therapy, a usual antibiotic with a non-antibiotic chemosensitizer. Nevertheless, for effective drug discovery, there is a prominent lack of tools required to understand the rules of permeation and accumulation into Gram-negative bacteria. By the use of a multidrug-resistant enterobacteria, we introduce a high-content screening procedure for chemosensitizers discovery by quantitative assessment of drug accumulation, alteration of barriers, and deduction of their activity profile. We assembled and analyzed a control chemicals library to perform the proof of concept. The analysis was based on real-time monitoring of the efflux alteration and measure of the influx increase in the presence of studied compounds in an automatized bio-assay. Then, synergistic activity of compounds with an antibiotic was studied and kinetic data reduction was performed which led to the calculation of a score for each barrier to be altered. PMID:29556218

Acridine-intercalator based hypoxia selective cytotoxins

DOEpatents

Papadopoulou-Rosenzweig, M.; Bloomer, W.D.

1994-03-15

Hypoxia selective cytotoxins of the general formula STR1 wherein n is from 1 to 5, and NO[sub 2] is in at least one of the 2, 4 or 5-positions of the imidazole are developed. Such compounds have utility as radiosensitizers and chemosensitizers. 9 figs.

Downregulation of a mitochondria associated protein SLP-2 inhibits tumor cell motility, proliferation and enhances cell sensitivity to chemotherapeutic reagents.

PubMed

Wang, Yueqi; Cao, Wenfeng; Yu, Zaicheng; Liu, Zhihua

2009-09-01

Results from tissue microarray in this study and our previous reports revealed that stomatin-like protein 2 (SLP-2) is notably associated with tumorigenesis and metastasis. Many members of stomatin family are involved in tumor as mitochondrial component, and recent study has revealed that SLP-2 may also function in mitochondria. To further investigate the function of SLP-2, we used siRNA target SLP-2. Data showed that knock-down of SLP-2 potently inhibited cell motility, proliferation and slightly altered cell cycle without any significant change of apoptosis. Moreover, by combined application with different chemotherapeutic reagents, we observed the enhancement of cell chemosensitivity by SLP-2 depletion. We also confirmed that, SLP-2 localizes in mitochondria, affects mitochondrial membrane potential (MMP) and ATP production. We conclude that, SLP-2 is a mitochondrial protein and therefore, functions in energy process by MMP maintenance, and subsequently affecting cell motility, proliferation and chemosensitivity.

Postchemotherapy changes in testicular germ cell tumours: biology and morphology.

PubMed

Berney, Daniel M; Lu, Yong-Jie; Shamash, Jonathan; Idrees, Muhammad

2017-01-01

Advances in modern chemotherapy and targeted treatments have resulted in lengthened survival in a variety of tumour types in the last decade. Increasingly in the 21st century, postchemotherapy resections are considered as a possible mode of treatment. Due to their exquisite chemosensitivity, resection of postchemotherapy masses has long been part of the armamentarium of treatment in testicular germ cell neoplasia, which has resulted in a variety of new morphological variants being described after treatment. Here we discuss the possible reasons for germ cell tumour chemosensitivity and hypotheses on the biological pathways leading to resistance to treatment, as well as an outline of the diverse morphology of those tumours which prove recalcitrant to standard treatment methods. The large range of morphologies and their diagnostic challenges may throw light upon the future problems to be encountered in non-germ cell solid tumour pathology, as the resection of postchemotherapy masses becomes increasingly important in patient management. © 2016 John Wiley & Sons Ltd.

Assessment of induced rat mammary tumour response to chemotherapy using the apparent diffusion coefficient of tissue water as determined by diffusion-weighted 1H-NMR spectroscopy in vivo.

PubMed

Lemaire, L; Howe, F A; Rodrigues, L M; Griffiths, J R

1999-03-01

Chemosensitivity of N-methyl-N-nitrosourea-induced rat mammary tumours treated with 5-fluorouracil at a dose of 100 mg kg(-1) i.p. was assessed by using diffusion-weighted 1H-MRS to measure the average diffusion coefficient (ADC) of water in the tumour tissue. ADC measurements prior to any therapy correlated positively with necrotic fraction. Tumours with low initial ADC (< 0.95 x 10(9) m2 s(-1)) showed an increase in ADC 7 days after treatment, whereas tumours with a high initial ADC (> 1.2 x 10(9) m2 s(-1)) showed a decrease. All tumours decreased significantly in volume (P < 0.05) 2, 5 and 7 days after treatment. At day 7 post-treatment, tumours with a high pre-treatment ADC started to regrow. The initial ADC value, as well as changes after treatment predict tumour chemosensitivity, which could be clinically relevant.

The multidrug transporter ABCG2 (BCRP) is inhibited by plant-derived cannabinoids.

PubMed

Holland, M L; Lau, D T T; Allen, J D; Arnold, J C

2007-11-01

Cannabinoids are used therapeutically for the palliation of the adverse side effects associated with cancer chemotherapy. However, cannabinoids also inhibit both the activity and expression of the multidrug transporter, P-glycoprotein in vitro. Here we address the interaction of cannabinol (CBN), cannabidiol (CBD) and delta 9-tetrahydrocannabinol (THC) with the related multidrug transporter, ABCG2. Cannabinoid inhibition of Abcg2/ABCG2 was assessed using flow cytometric analysis of substrate accumulation and ATPase activity assays. The cytotoxicity and chemosensitization by cannabinoids was determined with cell viability assays. Expression of cannabinoid and vanilloid receptors was assessed using reverse transcriptase polymerase chain reaction, and cannabinoid modulation of ABCG2 expression was examined using immunoblotting. CBN, CBD and THC increased the intracellular accumulation of the Abcg2/ABCG2 substrate, mitoxantrone, in an over-expressing cell line. The THC metabolite, (-)-11-nor-9-carboxy-delta 9-THC was much less potent. The plant cannabinoids inhibited both basal and substrate stimulated ATPase activity of human ABCG2. Cannabinoid cytotoxicity occurred in the absence of known cannabinoid cell surface receptors, and only at concentrations higher than those required for Abcg2/ABCG2 inhibition. Sub-toxic concentrations of the cannabinoids resensitized the overexpressing cell line to the cytotoxic effect of Abcg2/ABCG2 substrates, mitoxantrone and topotecan. This occurred in the absence of any effect on ABCG2 expression. Cannabinoids are novel Abcg2/ABCG2 inhibitors, reversing the Abcg2-mediated multidrug-resistant phenotype in vitro. This finding may have implications for the co-administration of cannabinoids with pharmaceuticals that are ABCG2 substrates.

KCNQ channels determine serotonergic modulation of ventral surface chemoreceptors and respiratory drive

PubMed Central

Hawryluk, Joanna M.; Moreira, Thiago S.; Takakura, Ana C.; Wenker, Ian C.; Tzingounis, Anastasios V.; Mulkey, Daniel K.

2012-01-01

Chemosensitive neurons in the retrotrapezoid nucleus (RTN) regulate breathing in response to CO2/H+ changes. Their activity is also sensitive to neuromodulatory inputs from multiple respiratory centers, and thus they serve as a key nexus of respiratory control. However, molecular mechanisms that control their activity and susceptibility to neuromodulation are unknown. Here, we show in vitro and in vivo that KCNQ channels are critical determinants of RTN neural activity. In particular, we find that pharmacological block of KCNQ channels (XE991, 10 μM) increased basal activity and CO2-responsivness of RTN neurons in rat brain slices; whereas KCNQ channel activation (retigabine 2–40 μM) silenced these neurons. Interestingly, we also find that KCNQ and apamin sensitive SK channels act synergistically to regulate firing rate of RTN chemoreceptors; simultaneous blockade of both channels led to a increase in CO2-responsivness. Furthermore, we also show that KCNQ channels but not SK channels are downstream effectors of serotonin modulation of RTN activity in vitro. In contrast, inhibition of KCNQ channel did not prevent modulation of RTN activity by Substance P or TRH; previously identified neuromodulators of RTN chemoreception. Importantly, we also show that KCNQ channels are critical for RTN activity in vivo. Inhibition of KCNQ channels lowered the CO2 threshold for phrenic nerve discharge in anesthetized rats and decreased the ventilatory response to serotonin in awake and anesthetized animals. Given that serotonergic dysfunction may contribute to respiratory failure, our findings suggest KCNQ channels as a new therapeutic avenue for respiratory complications associated with multiple neurological disorders. PMID:23175845

Loss of Runx2 sensitises osteosarcoma to chemotherapy-induced apoptosis

PubMed Central

Roos, Alison; Satterfield, Laura; Zhao, Shuying; Fuja, Daniel; Shuck, Ryan; Hicks, M John; Donehower, Lawrence A; Yustein, Jason T

2015-01-01

Background: Osteosarcoma (OS) is the most common bone malignancy in the paediatric population, principally affecting adolescents and young adults. Minimal advancements in patient prognosis have been made over the past two decades because of the poor understanding of disease biology. Runx2, a critical transcription factor in bone development, is frequently amplified and overexpressed in OS. However, the molecular and biological consequences of Runx2 overexpression remain unclear. Methods: si/shRNA and overexpression technology to alter Runx2 levels in OS cells. In vitro assessment of doxorubicin (doxo)-induced apoptosis and in vivo chemosensitivity studies. Small-molecule inhibitor of c-Myc transcriptional activity was used to assess its role. Results: Loss of Runx2 sensitises cells to doxo-induced apoptosis both in vitro and in vivo. Furthermore, in conjunction with chemotherapy, decreasing Runx2 protein levels activates both the intrinsic and extrinsic apoptotic pathways. Transplanted tumour studies demonstrated that loss of endogenous Runx2 protein expression enhances caspase-3 cleavage and tumour necrosis in response to chemotherapy. Finally, upon doxo-treated Runx2 knockdown OS cells there was evidence of enhanced c-Myc expression and transcriptional activity. Inhibition of c-Myc under these conditions resulted in decreased activation of apoptosis, therefore insinuating a role for c-Myc in dox-induced activation of apoptotic pathways. Conclusions: Therefore, we have established a novel molecular mechanism by which Runx2 provides a chemoprotective role in OS, indicating that in conjunction to standard chemotherapy, targeting Runx2 may be a new therapeutic strategy for patients with OS. PMID:26528706

A pH-Sensitive, Biobased Calcium Carbonate Aragonite Nanocrystal as a Novel Anticancer Delivery System

PubMed Central

Ismail, Maznah; Tengku Ibrahim, Tengku Azmi; Zakaria, Zuki Abu Bakar

2013-01-01

The synthesised biobased calcium carbonate nanocrystals had demonstrated to be an effective carrier for delivery of anticancer drug doxorubicin (DOX). The use of these nanocrystals displayed high levels of selectivity and specificity in achieving effective cancer cell death without nonspecific toxicity. These results confirmed that DOX was intercalated into calcium carbonate nanocrystals at high loading and encapsulation efficiency (4.8 and 96%, resp.). The CaCO3/DOX nanocrystals are relatively stable at neutral pH (7.4), resulting in slow release, but the nanocrystals progressively dissociated in acidic pH (4.8) regimes, triggering faster release of DOX. The CaCO3/DOX nanocrystals exhibited high uptake by MDA MB231 breast cancer cells and a promising potential delivery of DOX to target cells. In vitro chemosensitivity using MTT, modified neutral red/trypan blue assay, and LDH on MDA MB231 breast cancer cells revealed that CaCO3/DOX nanocrystals are more sensitive and gave a greater reduction in cell growth than free DOX. Our findings suggest that CaCO3 nanocrystals hold tremendous promise in the areas of controlled drug delivery and targeted cancer therapy. PMID:24324966

Lansoprazole induces sensitivity to suboptimal doses of paclitaxel in human melanoma.

PubMed

Azzarito, Tommaso; Venturi, Giulietta; Cesolini, Albino; Fais, Stefano

2015-01-28

Tumor acidity is now considered an important determinant of drug-resistance and tumor progression, and anti-acidic approaches, such as Proton Pump inhibitors (PPIs), have demonstrated promising antitumor and chemo-sensitizing efficacy. The main purpose of the present study was to evaluate the possible PPI-induced sensitization of human melanoma cells to Paclitaxel (PTX). Our results show that PTX and the PPI Lansoprazole (LAN) combination was extremely efficient against metastatic melanoma cells, as compared to the single treatments, both in vitro and in vivo. We also showed that acidity plays an important role on the anti-tumor activity of these drugs, being detrimental for PTX activity, while crucial for the synergistic effect of PTX following pretreatment with LAN, due to its nature of pro-drug needing protonation for a full activation. We obtained straightforward results in a human melanoma xenograft model combining well tolerated LAN doses with suboptimal and poorly toxic doses of PTX. With this study we provide a clear evidence that the PPI LAN may be included in new combined therapy of human melanoma together with low doses of PTX. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Ganoderma spp.: A Promising Adjuvant Treatment for Breast Cancer

PubMed Central

Suárez-Arroyo, Ivette J.; Loperena-Alvarez, Yaliz; Rosario-Acevedo, Raysa; Martínez-Montemayor, Michelle M.

2017-01-01

For the past several decades, cancer patients in the U.S. have chosen the use of natural products as an alternative or complimentary medicine approach to treat or improve their quality of life via reduction or prevention of the side effects during or after cancer treatment. The genus Ganoderma includes about 80 species of mushrooms, of which several have been used for centuries in traditional Asian medicine for their medicinal properties, including anticancer and immunoregulatory effects. Numerous bioactive compounds seem to be responsible for their healing effects. Among the approximately 400 compounds produced by Ganoderma spp., triterpenes, peptidoglycans and polysaccharides are the major physiologically-active constituents. Ganoderma anticancer effects are attributed to its efficacy in reducing cancer cell survival and growth, as well as by its chemosensitizing role. In vitro and in vivo studies have been conducted in various cancer cells and animal models; however, in this review, we focus on Ganoderma’s efficacy on breast cancers. Evidence shows that some species of Ganoderma have great potential as a natural therapeutic for breast cancer. Nevertheless, further studies are needed to investigate their potential in the clinical setting and to translate our basic scientific findings into therapeutic interventions for cancer patients. PMID:28758107

The Role of Mitochondrial TCA Cycle Enzymes in Determining Prostate Cancer Chemosensitivity

DTIC Science & Technology

2012-03-01

mitochondrial OAA measurement is performed by a commercial kit from Biovision . Briefly, whole cell lysates or mitochondria fraction were obtained from... Biovision based on the manufacturer protocols. 2) Cellular oxygen consumption and reactive oxygen (ROS) production. One of the metabolic consequences of

Mechanisms of CO2/H+ chemoreception by respiratory rhythm generator neurons in the medulla from newborn rats in vitro.

PubMed

Kawai, Akira; Onimaru, Hiroshi; Homma, Ikuo

2006-04-15

We investigated mechanisms of CO(2)/H(+) chemoreception in the respiratory centre of the medulla by measuring membrane potentials of pre-inspiratory neurons, which are putative respiratory rhythm generators, in the brainstem-spinal cord preparation of the neonatal rat. Neuronal response was tested by changing superfusate CO(2) concentration from 2% to 8% at constant HCO(3)(-) concentration (26 mm) or by changing pH from 7.8 to 7.2 by reducing HCO(3)(-) concentration at constant CO(2) (5%). Both respiratory and metabolic acidosis lead to depolarization of neurons with increased excitatory synaptic input and increased burst rate. Respiratory acidosis potentiated the amplitude of the neuronal drive potential. In the presence of tetrodotoxin (TTX), membrane depolarization persisted during respiratory and metabolic acidosis. However, the depolarization was smaller than that before application of TTX, which suggests that some neurons are intrinsically, and others synaptically, chemosensitive to CO(2)/H(+). Application of Ba(2+) blocked membrane depolarization by respiratory acidosis, whereas significant depolarization in response to metabolic acidosis still remained after application of Cd(2+) and Ba(2+). We concluded that the intrinsic responses to CO(2)/H(+)changes were mediated by potassium channels during respiratory acidosis, and that some other mechanisms operate during metabolic acidosis. In low-Ca(2+), high-Mg(2+) solution, an increased CO(2) concentration induced a membrane depolarization with a simultaneous increase of the burst rate. Pre-inspiratory neurons could adapt their baseline membrane potential to external CO(2)/H(+) changes by integration of these mechanisms to modulate their burst rates. Thus, pre-inspiratory neurons might play an important role in modulation of respiratory rhythm by central chemoreception in the brainstem-spinal cord preparation.

Mechanisms of CO2/H+ chemoreception by respiratory rhythm generator neurons in the medulla from newborn rats in vitro

PubMed Central

Kawai, Akira; Onimaru, Hiroshi; Homma, Ikuo

2006-01-01

We investigated mechanisms of CO2/H+ chemoreception in the respiratory centre of the medulla by measuring membrane potentials of pre-inspiratory neurons, which are putative respiratory rhythm generators, in the brainstem–spinal cord preparation of the neonatal rat. Neuronal response was tested by changing superfusate CO2 concentration from 2% to 8% at constant HCO3− concentration (26 mm) or by changing pH from 7.8 to 7.2 by reducing HCO3− concentration at constant CO2 (5%). Both respiratory and metabolic acidosis lead to depolarization of neurons with increased excitatory synaptic input and increased burst rate. Respiratory acidosis potentiated the amplitude of the neuronal drive potential. In the presence of tetrodotoxin (TTX), membrane depolarization persisted during respiratory and metabolic acidosis. However, the depolarization was smaller than that before application of TTX, which suggests that some neurons are intrinsically, and others synaptically, chemosensitive to CO2/H+. Application of Ba2+ blocked membrane depolarization by respiratory acidosis, whereas significant depolarization in response to metabolic acidosis still remained after application of Cd2+ and Ba2+. We concluded that the intrinsic responses to CO2/H+changes were mediated by potassium channels during respiratory acidosis, and that some other mechanisms operate during metabolic acidosis. In low-Ca2+, high-Mg2+ solution, an increased CO2 concentration induced a membrane depolarization with a simultaneous increase of the burst rate. Pre-inspiratory neurons could adapt their baseline membrane potential to external CO2/H+ changes by integration of these mechanisms to modulate their burst rates. Thus, pre-inspiratory neurons might play an important role in modulation of respiratory rhythm by central chemoreception in the brainstem–spinal cord preparation. PMID:16469786

Preclinical Investigations of PM01183 (Lurbinectedin) as a Single Agent or in Combination with Other Anticancer Agents for Clear Cell Carcinoma of the Ovary

PubMed Central

Takahashi, Ryoko; Mabuchi, Seiji; Kawano, Mahiru; Sasano, Tomoyuki; Matsumoto, Yuri; Kuroda, Hiromasa; Kozasa, Katsumi; Hashimoto, Kae; Sawada, Kenjiro; Kimura, Tadashi

2016-01-01

Objective The objective of this study was to evaluate the antitumor effects of lurbinectedin as a single agent or in combination with existing anticancer agents for clear cell carcinoma (CCC) of the ovary, which is regarded as an aggressive, chemoresistant, histological subtype. Methods Using human ovarian CCC cell lines, the antitumor effects of lurbinectedin, SN-38, doxorubicin, cisplatin, and paclitaxel as single agents were assessed using the MTS assay. Then, the antitumor effects of combination therapies involving lurbinectedin and 1 of the other 4 agents were evaluated using isobologram analysis to examine whether these combinations displayed synergistic effects. The antitumor activity of each treatment was also examined using cisplatin-resistant and paclitaxel-resistant CCC sublines. Finally, we determined the effects of mTORC1 inhibition on the antitumor activity of lurbinectedin-based chemotherapy. Results Lurbinectedin exhibited significant antitumor activity toward chemosensitive and chemoresistant CCC cells in vitro. An examination of mouse CCC cell xenografts revealed that lurbinectedin significantly inhibits tumor growth. Among the tested combinations, lurbinectedin plus SN-38 resulted in a significant synergistic effect. This combination also had strong synergistic effects on both the cisplatin-resistant and paclitaxel-resistant CCC cell lines. Everolimus significantly enhanced the antitumor activity of lurbinectedin-based chemotherapies. Conclusions Lurbinectedin, a new agent that targets active transcription, exhibits antitumor activity in CCC when used as a single agent and has synergistic antitumor effects when combined with irinotecan. Our results indicate that lurbinectedin is a promising agent for treating ovarian CCC, both as a first-line treatment and as a salvage treatment for recurrent lesions that develop after platinum-based or paclitaxel treatment. PMID:26986199

BAG3 upregulates Mcl-1 through downregulation of miR-29b to induce anticancer drug resistance in ovarian cancer.

PubMed

Sugio, Asuka; Iwasaki, Masahiro; Habata, Shutaro; Mariya, Tasuku; Suzuki, Miwa; Osogami, Hiroyuki; Tamate, Masato; Tanaka, Ryoichi; Saito, Tsuyoshi

2014-09-01

Ovarian cancer is the leading cause of death from gynecologic cancer, reflecting its often late diagnosis and its chemoresistance. We identified a set of microRNAs whose expression is altered upon BAG3 knockdown. Our primary objective was to examine the relationships between BAG3, miR-29b and Mcl-1, an antiapoptotic Bcl-2 family protein, in ovarian cancer cells. Ovarian cancer cells were cultured and their responsiveness to paclitaxel was tested. Microarray analysis was performed to identify microRNAs differentially expressed in ES2 BAG3 knockdown ovarian cancer cells and their control cells. Primary ovarian cancer tissues were obtained from 56 patients operated on for ovarian cancer. The patients' clinical and pathological data were obtained from their medical records. BAG3 knockdown increased the chemosensitivity to paclitaxel of ES2 ovarian clear cell carcinoma cells to a greater degree than AMOC2 serous adenocarcinoma cells. qRT-PCR analysis showed that miR-29b expression was significantly upregulated in primary cancer tissue expressing low levels of BAG3, as compared to tissue expressing high levels. Moreover, levels of miR-29b correlated significantly with progression-free survival. Upregulation of miR-29b also reduced levels of Mcl-1 and sensitized ES2 cells to low-dose paclitaxel. BAG3 knockdown appears to downregulate expression of Mcl-1 through upregulation of miR-29b, thereby increasing the chemosensitivity of ovarian clear cell carcinoma cells. This suggests that BAG3 is a key determinant of the responsiveness of ovarian cancer cells, especially clear cell carcinoma, to paclitaxel and that BAG3 may be a useful therapeutic target for the treatment of ovarian cancer. Copyright © 2014 Elsevier Inc. All rights reserved.

IDH1 R132H mutation regulates glioma chemosensitivity through Nrf2 pathway.

PubMed

Li, Kaishu; Ouyang, Leping; He, Mingliang; Luo, Ming; Cai, Wangqing; Tu, Yalin; Pi, Rongbiao; Liu, Anmin

2017-04-25

Numerous studies have reported that glioma patients with isocitrate dehydrogenase 1(IDH1) R132H mutation are sensitive to temozolomide treatment. However, the mechanism of IDH1 mutations on the chemosensitivity of glioma remains unclear. In this study, we investigated the role and the potential mechanism of Nrf2 in IDH1 R132H-mediated drug resistance. Wild type IDH1 (R132H-WT) and mutant IDH1 (R132H) plasmids were constructed. Stable U87 cells and U251 cells overexpressing IDH1 were generated. Phenotypic differences between IDH1-WT and IDH1 R132H overexpressing cells were evaluated using MTT, cell colony formation assay, scratch test assay and flow cytometry. Expression of IDH1 and its associated targets, nuclear factor-erythroid 2-related factor 2 (Nrf2), NAD(P)H quinine oxidoreductase 1 (NQO1), multidrug resistant protein 1 (MRP1) and p53 were analyzed. The IDH1 R132H overexpressing cells were more sensitive to temozolomide than WT and the control, and Nrf2 was significantly decreased in IDH1 R132H overexpressing cells. We found that knocking down Nrf2 could decrease resistance to temozolomide. The nuclear translocation of Nrf2 in IDH1 R132H overexpressing cells was lower than the WT and the control groups after temozolomide treatment. When compared with WT cells, NQO1 expression was reduced in IDH1 R132H cells, especially after temozolomide treatment. P53 was involved in the resistance mechanism of temozolomide mediated by Nrf2 and NQO1. Nrf2 played an important role in IDH1 R132H-mediated drug resistance. The present study provides new insight for glioma chemotherapy with temozolomide.

IDH1 R132H mutation regulates glioma chemosensitivity through Nrf2 pathway

PubMed Central

Luo, Ming; Cai, Wangqing; Tu, Yalin; Pi, Rongbiao; Liu, Anmin

2017-01-01

Purpose Numerous studies have reported that glioma patients with isocitrate dehydrogenase 1(IDH1) R132H mutation are sensitive to temozolomide treatment. However, the mechanism of IDH1 mutations on the chemosensitivity of glioma remains unclear. In this study, we investigated the role and the potential mechanism of Nrf2 in IDH1 R132H-mediated drug resistance. Methods Wild type IDH1 (R132H-WT) and mutant IDH1 (R132H) plasmids were constructed. Stable U87 cells and U251 cells overexpressing IDH1 were generated. Phenotypic differences between IDH1-WT and IDH1 R132H overexpressing cells were evaluated using MTT, cell colony formation assay, scratch test assay and flow cytometry. Expression of IDH1 and its associated targets, nuclear factor-erythroid 2-related factor 2 (Nrf2), NAD(P)H quinine oxidoreductase 1 (NQO1), multidrug resistant protein 1 (MRP1) and p53 were analyzed. Results The IDH1 R132H overexpressing cells were more sensitive to temozolomide than WT and the control, and Nrf2 was significantly decreased in IDH1 R132H overexpressing cells. We found that knocking down Nrf2 could decrease resistance to temozolomide. The nuclear translocation of Nrf2 in IDH1 R132H overexpressing cells was lower than the WT and the control groups after temozolomide treatment. When compared with WT cells, NQO1 expression was reduced in IDH1 R132H cells, especially after temozolomide treatment. P53 was involved in the resistance mechanism of temozolomide mediated by Nrf2 and NQO1. Conclusions Nrf2 played an important role in IDH1 R132H-mediated drug resistance. The present study provides new insight for glioma chemotherapy with temozolomide. PMID:28427200

Curcumin synergizes with 5-fluorouracil by impairing AMPK/ULK1-dependent autophagy, AKT activity and enhancing apoptosis in colon cancer cells with tumor growth inhibition in xenograft mice.

PubMed

Zhang, Pan; Lai, Ze-Lin; Chen, Hui-Fen; Zhang, Min; Wang, An; Jia, Tao; Sun, Wen-Qin; Zhu, Xi-Min; Chen, Xiao-Feng; Zhao, Zheng; Zhang, Jun

2017-12-22

Chemoresistance is a major obstacle that limits the benefits of 5-Fluorouracil (5-Fu)-based chemotherapy for colon cancer patients. Autophagy is an important cellular mechanism underlying chemoresistance. Recent research advances have given new insights into the use of natural bioactive compounds to overcome chemoresistance in colon cancer chemotherapy. As one of the multitargeted and safer phytomedicines, curcumin has been reported to work as cancer-specific chemosensitizer, presumably via induction of autophagic signaling pathways. The precise therapeutic effect of curcumin on autophagy in determining tumorous cells' fate, however, remains unclear. This study was conducted to investigate the differential modulations of the treatments either with 5-Fu alone or 5-Fu combined with curcumin on cellular autophagic responses and viabilities in the human colon cancer cells HCT116 and HT29, and explore molecular signaling transductions underlying the curcumin-mediated autophagic changes and potentiation of 5-Fu's cytotoxicity in vitro and in vivo. Cell proliferation assay and morphology observation were used to identify the cytotoxicity of different combinations of curcumin and 5-Fu in HCT116 and HT29 cells. Cell immunofluorescence assay, Flow cytometry and Western blot were employed to detect changes of autophagy and the autophagy-related signaling pathways in the colon cancer cells and/or xenograft mice. Curcumin could significantly augment the cytotoxicity of 5-Fu to the tumorous cells, and the pre-treatment with curcumin followed by 5-Fu (pre-Cur) proved to be the most effective one compared to other two combinations. The chemosensitizing role of curcumin might attribute to the autophagy turnover from being activated in 5-Fu mono-treatment to being inhibited in the pre-Cur treatment as indicated by the changes in expression of beclin-1, p62 and LC3II/LC3I and the intensity of Cyto-ID Green staining. The autophagic alterations appeared to be contributed by down-regulation of not only the phospho-Akt and phospho-mTOR expressions but the phospho-AMPK and phospho-ULK1 levels as well. The cellular activation of AMPK by addition of A-769662 to the pre-Cur combination resulted in reversed changes in expressions of the autophagy protein markers and apoptotic status compared to those of the pre-Cur combination treatment. The findings were validated in the xenograft mice, in which the tumor growth was significantly suppressed in the mice with 25-day combination treatment, and meanwhile expressions of the autophagy markers, P-AMPK and P-ULK1 were all reversely altered in line with those observed in HCT116 cells. Pre-treatment with curcumin followed by 5-Fu may mediate autophagy turnover both in vitro and in vivo via AMPK/ULK1-dependent autophagy inhibition and AKT modulation, which may account for the increased susceptibility of the colon cancer cells/xenograft to the cytotoxicity of 5-Fu.

Augmenting the activity of antifungal agents against aspergilli using structural analogues of benzoic acid as chemosensitizing agents

USDA-ARS?s Scientific Manuscript database

Several benzoic acid analogs showed antifungal activity against strains of Aspergillus flavus, A. fumigatus and A. terreus, causative agents of human aspergillosis. Structure-activity analysis revealed that antifungal activities of benzoic and gallic acids increased by addition of a methyl, methoxyl...

Cinnamic acid analogs as intervention catalysts for overcoming antifungal tolerance

USDA-ARS?s Scientific Manuscript database

Antifungal potency of thirty-three cinnamic acid derivatives was investigated. The efficacy of caspofungin (CAS) or octyl gallate (OG), the cell wall disrupting agents, was augmented by 4-chloro-a-methyl- or 4-methylcinnamic acid screened. Synergistic chemosensitization by 4-chloro-a-methyl- or 4-me...

Chemosensitization of Breast Cancer Cells to Chemotherapeutic Agents by 3,3’diindolylmethane (DIM)

DTIC Science & Technology

2006-08-01

therapies. However, further in-depth investigations are needed to establish the cause and effect relationship of survivin gene regulation and 3,3V...Basu GD, Pathangey LB, Tinder TL, et al. Cyclooxygenase-2 inhibitor induces apoptosis in breast cancer cells in an in vivo model of spontaneous

Augmenting the activity of antifungal agents against aspergilli using structural analogues of benzoic acid as chemosensitizing agents

USDA-ARS?s Scientific Manuscript database

Structure-activity analysis revealed that antifungal activities of benzoic and gallic acids were increased against strains of Aspergillus flavus, A. fumigatus and A. terreus, causative agents of human aspergillosis, by addition of a methyl, methoxyl or a chloro group at position 4 of the aromatic ri...

Augmenting the activity of monoterpenoid phenols against fungal pathogens using 2-hydroxy-4-methoxybenzaldehyde that target cell wall integrity

USDA-ARS?s Scientific Manuscript database

The aim of this study was to identify benzaldehydes to which the fungal cell wall integrity signaling mutants showed increased sensitivity. These compounds could then function as chemosensitizing agents in combination with monoterpenoid phenols, such as carvacrol or thymol, to enhance antifungal act...

Consensus-phenotype integration of transcriptomic and metabolomic data implies a role for metabolism in the chemosensitivity of tumour cells.

PubMed

Cavill, Rachel; Kamburov, Atanas; Ellis, James K; Athersuch, Toby J; Blagrove, Marcus S C; Herwig, Ralf; Ebbels, Timothy M D; Keun, Hector C

2011-03-01

Using transcriptomic and metabolomic measurements from the NCI60 cell line panel, together with a novel approach to integration of molecular profile data, we show that the biochemical pathways associated with tumour cell chemosensitivity to platinum-based drugs are highly coincident, i.e. they describe a consensus phenotype. Direct integration of metabolome and transcriptome data at the point of pathway analysis improved the detection of consensus pathways by 76%, and revealed associations between platinum sensitivity and several metabolic pathways that were not visible from transcriptome analysis alone. These pathways included the TCA cycle and pyruvate metabolism, lipoprotein uptake and nucleotide synthesis by both salvage and de novo pathways. Extending the approach across a wide panel of chemotherapeutics, we confirmed the specificity of the metabolic pathway associations to platinum sensitivity. We conclude that metabolic phenotyping could play a role in predicting response to platinum chemotherapy and that consensus-phenotype integration of molecular profiling data is a powerful and versatile tool for both biomarker discovery and for exploring the complex relationships between biological pathways and drug response.

Let-7 Sensitizes KRAS Mutant Tumor Cells to Chemotherapy

PubMed Central

Dai, Xin; Jiang, Ying; Tan, Chalet

2015-01-01

KRAS is the most commonly mutated oncogene in human cancers and is associated with poor prognosis and drug resistance. Let-7 is a family of tumor suppressor microRNAs that are frequently suppressed in solid tumors, where KRAS mutations are highly prevalent. In this study, we investigated the potential use of let-7 as a chemosensitizer. We found that let-7b repletion selectively sensitized KRAS mutant tumor cells to the cytotoxicity of paclitaxel and gemcitabine. Transfection of let-7b mimic downregulated the expression of mutant but not wild-type KRAS. Combination of let-7b mimic with paclitaxel or gemcitabine diminished MEK/ERK and PI3K/AKT signaling concurrently, triggered the onset of apoptosis, and reverted the epithelial-mesenchymal transition in KRAS mutant tumor cells. In addition, let-7b repletion downregulated the expression of β-tubulin III and ribonucleotide reductase subunit M2, two proteins known to mediate tumor resistance to paclitaxel and gemcitabine, respectively. Let-7 may represent a new class of chemosensitizer for the treatment of KRAS mutant tumors. PMID:25946136

Chronic hypoxia suppresses the CO2 response of solitary complex (SC) neurons from rats.

PubMed

Nichols, Nicole L; Wilkinson, Katherine A; Powell, Frank L; Dean, Jay B; Putnam, Robert W

2009-09-30

We studied the effect of chronic hypobaric hypoxia (CHx; 10-11% O(2)) on the response to hypercapnia (15% CO(2)) of individual solitary complex (SC) neurons from adult rats. We simultaneously measured the intracellular pH and firing rate responses to hypercapnia of SC neurons in superfused medullary slices from control and CHx-adapted adult rats using the blind whole cell patch clamp technique and fluorescence imaging microscopy. We found that CHx caused the percentage of SC neurons inhibited by hypercapnia to significantly increase from about 10% up to about 30%, but did not significantly alter the percentage of SC neurons activated by hypercapnia (50% in control vs. 35% in CHx). Further, the magnitudes of the responses of SC neurons from control rats (chemosensitivity index for activated neurons of 166+/-11% and for inhibited neurons of 45+/-15%) were the same in SC neurons from CHx-adapted rats. This plasticity induced in chemosensitive SC neurons by CHx appears to involve intrinsic changes in neuronal properties since they were the same in synaptic blockade medium.

Targeting acid sphingomyelinase with anti-angiogenic chemotherapy.

PubMed

Jacobi, Jeanna; García-Barros, Mónica; Rao, Shyam; Rotolo, Jimmy A; Thompson, Chris; Mizrachi, Aviram; Feldman, Regina; Manova, Katia; Bielawska, Alicja; Bielawska, Jacek; Fuks, Zvi; Kolesnick, Richard; Haimovitz-Friedman, Adriana

2017-01-01

Despite great promise, combining anti-angiogenic and conventional anti-cancer drugs has produced limited therapeutic benefit in clinical trials, presumably because mechanisms of anti-angiogenic tissue response remain only partially understood. Here we define a new paradigm, in which anti-angiogenic drugs can be used to chemosensitize tumors by targeting the endothelial acid sphingomyelinase (ASMase) signal transduction pathway. We demonstrate that paclitaxel and etoposide, but not cisplatin, confer ASMase-mediated endothelial injury within minutes. This rapid reaction is required for human HCT-116 colon cancer xenograft complete response and growth delay. Whereas VEGF inhibits ASMase, anti-VEGFR2 antibodies de-repress ASMase, enhancing endothelial apoptosis and drug-induced tumor response in asmase +/+ , but not in asmase -/- , hosts. Such chemosensitization occurs only if the anti-angiogenic drug is delivered 1-2h before chemotherapy, but at no other time prior to or post chemotherapy. Our studies suggest that precisely-timed administration of anti-angiogenic drugs in combination with ASMase-targeting anti-cancer drugs is likely to optimize anti-tumor effects of systemic chemotherapy. This strategy warrants evaluation in future clinical trials. Copyright © 2016 Elsevier Inc. All rights reserved.

Liposarcoma: multimodality management and future targeted therapies

PubMed Central

Crago, Aimee M.; Dickson, Mark A.

2016-01-01

SYNOPSIS There are three biologic groups of liposarcoma: well- and dedifferentiated liposarcoma (WD/DDLS), myxoid/round cell liposarcoma (M/RCLS) and pleomorphic liposarcoma. WD/DDLS is characterized by amplification of 12q13-15 (including the oncogenes MDM2 and CDK4), M/RCLS by FUS-DDIT3 translocations, and pleomorphic liposarcoma by loss of p53 and Rb. In all three groups, complete surgical resection is central in treatment aimed at cure and is based on grade. Radiation can reduce risk of local recurrence in high-grade lesions or minimize surgical morbidity in the highly radiosensitive M/RCLS group. The biologic groups differ greatly in their chemosensitivity, so adjuvant chemotherapy is selectively utilized in chemosensitive histologies with metastatic potential (i.e. round cell and pleomorphic liposarcomas) but not in the relatively resistant subtype DDLS. An improved understanding of the genetic aberrations that lead to liposarcoma initiation is also allowing for the rapid development of targeted therapies for liposarcoma. Among such therapies are CDK4 inhibitors in WD/DDLS and trabectedin, which prevents FUS-DDIT3 binding to DNA, in M/RCLS. PMID:27591497

Apigenin sensitizes hepatocellular carcinoma cells to doxorubic through regulating miR-520b/ATG7 axis.

PubMed

Gao, Ai-Mei; Zhang, Xiao-Yu; Hu, Juan-Ni; Ke, Zun-Ping

2018-01-25

Chemo-resistance is a serious obstacle for successful treatment of cancer. Apigenin, a dietary flavonoid, has been reported as an anticancer drug in various malignant cancers. This study aimed to investigate the potential chemo-sensitization effect of apigenin in doxorubicin-resistant hepatocellular carcinoma cell line BEL-7402/ADM. We observed that apigenin significantly enhanced doxorubicin sensitivity, induced miR-520b expression and inhibited ATG7-dependent autophagy in BEL-7402/ADM cells. In addition, we also showed that miR-520b mimics increased doxorubicin sensitivity and inhibited ATG7-dependent autophagy. Meanwhile, we indicated that ATG7 was a potential target of miR-520b. Furthermore, APG inhibited the growth of hepatocellar carcinoma xenografts in nude mice by up-regulating miR-520b and inhibiting ATG7. Our finding provides evidence that apigenin sensitizes BEL-7402/ADM cells to doxorubicin through miR-520b/ATG7 pathway, which furtherly supports apigenin as a potential chemo-sensitizer for hepatocellular carcinoma. Copyright © 2017 Elsevier B.V. All rights reserved.

Silibinin suppresses NPM-ALK, potently induces apoptosis and enhances chemosensitivity in ALK-positive anaplastic large cell lymphoma.

PubMed

Molavi, Ommoleila; Samadi, Nasser; Wu, Chengsheng; Lavasanifar, Afsaneh; Lai, Raymond

2016-05-01

Nucleophosmin-anaplastic lymphoma kinase (NPM-ALK), an oncogenic fusion protein carrying constitutively active tyrosine kinase, is known to be central to the pathogenesis of ALK-positive anaplastic large cell lymphoma (ALK+ALCL). Here, it is reported that silibinin, a non-toxic naturally-occurring compound, potently suppressed NPM-ALK and effectively inhibited the growth and soft agar colony formation of ALK+ALCL cells. By western blots, it was found that silibinin efficiently suppressed the phosphorylation/activation of NPM-ALK and its key substrates/downstream mediators (including STAT3, MEK/ERK and Akt) in a time- and dose-dependent manner. Correlating with these observations, silibinin suppressed the expression of Bcl-2, survivin and JunB, all of which are found to be upregulated by NPM-ALK and pathogenetically important in ALK+ALCL. Lastly, silibinin augmented the chemosensitivity of ALK+ALCL cells to doxorubicin, particularly the small cell sub-set expressing the transcriptional activity of Sox2, an embryonic stem cell marker. To conclude, the findings suggest that silibinin might be useful in treating ALK+ALCL.

Chemosensitivity of the osphradium of the pond snail Lymnaea stagnalis

PubMed

Wedemeyer; Schild

1995-01-01

The osphradium of the pond snail Lymnaea stagnalis was studied to determine the stimuli to which this organ responds. The following stimuli were tested: hypoxia, hypercapnia, a mixture of amino acids, a mixture of citralva and amyl acetate and a mixture of lyral, lilial and ethylvanillin. The mean nerve activity consistently increased with elevated PCO2, whereas hypoxia produced variable effects. The nerve activity became rhythmic upon application of citralva and amyl acetate, but it increased in a non-rhythmic way upon application of the other two odorant mixtures tested. Whole-cell patch-clamp recordings were made from a group of 15 neurones that lay next to the issuing osphradial nerve, to determine whether ganglion cells were involved in olfactory signal processing. All neurones tested responded to at least one of the three mixtures of odorants. Both excitatory and inhibitory responses occurred. Our results indicate that the osphradium of the pond snail Lymnaea stagnalis is sensitive to elevated PCO2 as well as to three different classes of odorants. In addition, at least some neurones within the osphradium are involved in the processing of olfactory information.

Heat Shock Protein 27-Targeted Heptapeptide of the PKC{Delta} Catalytic V5 Region Sensitizes Tumors With Radio- and Chemoresistance

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

Lee, Hae-June; Kim, Eun-Ho; School of Life Sciences and Biotechnology, Korea University, Seoul

Purpose: Previous data suggest that the PKC{delta} catalytic V5 (PKC{delta}-V5) heptapeptide (HEPT) (FEQFLDI) binds HSP27 and blocks HSP27-mediated radio- or chemoresistance. Here we investigated further the in vivo function of the PKC{delta}-V5 HEPT. Methods and Materials: Labeling of HEPT with Cy5.5 or fluorescein isothiocyanate was performed to evaluate in vitro or in vivo distribution of HEPT. A clonogenic survival assay, flow cytometry, and Western blotting of cleaved caspase-3 were performed to determine in vitro sensitization effects of HEPT plus ionizing radiation (IR) versus IR alone or those of HEPT plus cisplatin(Cis) versus Cis alone. A nude mouse xenografting system wasmore » also applied to detect in vivo sensitizing effects of HEPT. Results: HEPT efficiently bound to HSP27 and showed sensitization after combined treatment with IR versus treatment with Cis alone in NCI-H1299 lung carcinoma cells, with higher HSP27 expression, which was similar to that of combined treatment with IR or with Cis alone in NCI-H460 lung carcinoma cells with lower HSP27 expression. In vivo image analysis using Cy5.5-labeled HEPT showed that HEPT was retained in HSP27-overexpressing cancer cells after xenografting to nude mice. Combined treatment of HEPT with IR versus that with Cis alone in xenografted mice showed that HEPT increased radio- or chemosensitization in NCI-H1299 cells compared to that in mice xenografted with NCI-H460 cells. Conclusions: The novel PKC{delta}-V5 HEPT may help overcome HSP27-mediated radio- or chemoresistance.« less

Defeating EpCAM(+) liver cancer stem cells by targeting chromatin remodeling enzyme CHD4 in human hepatocellular carcinoma.

PubMed

Nio, Kouki; Yamashita, Taro; Okada, Hikari; Kondo, Mitsumasa; Hayashi, Takehiro; Hara, Yasumasa; Nomura, Yoshimoto; Zeng, Sha Sha; Yoshida, Mariko; Hayashi, Tomoyuki; Sunagozaka, Hajime; Oishi, Naoki; Honda, Masao; Kaneko, Shuichi

2015-11-01

Hepatocellular carcinoma is composed of a subset of cells with enhanced tumorigenicity and chemoresistance that are called cancer stem (or stem-like) cells. We explored the role of chromodomain-helicase-DNA-binding protein 4, which is encoded by the CHD4 gene and is known to epigenetically control gene regulation and DNA damage responses in EpCAM(+) liver cancer stem cells. Gene and protein expression profiles were determined by microarray and immunohistochemistry in 245 and 144 hepatocellular carcinoma patients, respectively. The relationship between gene/protein expression and prognosis was examined. The functional role of CHD4 was evaluated in primary hepatocellular carcinoma cells and in cell lines in vitro and in vivo. CHD4 was abundantly expressed in EpCAM(+) hepatocellular carcinoma with expression of hepatic stem cell markers and poor prognosis in two independent cohorts. In cell lines, CHD4 knockdown increased chemosensitivity and CHD4 overexpression induced epirubicin chemoresistance. To inhibit the functions of CHD4 that are mediated through histone deacetylase and poly (ADP-ribose) polymerase, we evaluated the effect of the histone deacetylase inhibitor suberohydroxamic acid and the poly (ADP-ribose) polymerase inhibitor AG-014699. Treatment with either suberohydroxamic acid or AG-014699 reduced the number of EpCAM(+) liver cancer stem cells in vitro, and suberohydroxamic acid and AG-014699 in combination successfully inhibited tumor growth in a mouse xenograft model. CHD4 plays a pivotal role in chemoresistance and the maintenance of stemness in liver cancer stem cells and is therefore a good target for the eradication of hepatocellular carcinoma. Copyright © 2015 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

MicroRNA-100 regulates pancreatic cancer cells growth and sensitivity to chemotherapy through targeting FGFR3.

PubMed

Li, Zhipeng; Li, Xu; Yu, Chao; Wang, Min; Peng, Feng; Xiao, Jie; Tian, Rui; Jiang, Jianxin; Sun, Chengyi

2014-12-01

We intended to investigate the role of microRNA 100 (miR-100) in regulating pancreatic cancer cells' growth in vitro and tumor development in vivo. QTR-PCR was used to examine the expression of miR-100 in pancreatic cancer cell lines and tumor cells from human patients. Lentivirual vector containing miR-100 mimics (lv-miR-100) was used to overexpress miR-100 in MIA PaCa-2 and FCPAC-1 cells. The effects of overexpressing miR-100 on pancreatic cancer cell proliferation and chemosensitivity to cisplatin were examined by cell proliferation essay in vitro. MIA PaCa-2 cells with endogenously overexpressed miR-100 were transplanted into null mice to examine tumor growth in vivo. The predicted target of miR-100, fibroblast growth factor receptor 3 (FGFR3), was downregulated by siRNA to examine its effect on pancreatic cancer cells. We found miR-100 was markedly underexpressed in both pancreatic cancer cell lines and tumor cells from patients. In cancer cells, transfection of lv-miR-100 was able to upregulate endogenous expression of miR-100, inhibited cancer cell proliferation, and increased sensitivities to cisplatin. Overexpressing miR-100 led to significant inhibition on tumor formation in vivo. Luciferase essay showed FGFR3 was direct target of miR-100. FGFR3 was significantly downregulated by overexpressing miR-100 in pancreatic cancer cells and knocking down FGFR3 by siRNA exerted similar effect as miR-100. Our study demonstrated that miR-100 played an important role in pancreatic cancer development, possibly through targeting FGFR3. It may become a new therapeutic target for gene therapy in patients suffered from pancreatic cancer.

Cell diameter measurements obtained with a handheld cell counter could be used as a surrogate marker of G2/M arrest and apoptosis in colon cancer cell lines exposed to SN-38

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

Tahara, Makiko; Department of Gastrointestinal Surgery, Jichi Medical University, Shimotsuke, Tochigi; Inoue, Takeshi

2013-05-17

Highlights: •Chemo-sensitivity to SN-38 was assayed by the automated cell counter. •Colon cancer cell line, HCT116 cells were more sensitive to SN-38 than HT29 cells. •Increase of cell size reflects G2/M arrest. •Appearance of small particles indicates cell apoptosis. -- Abstract: In vitro assessment of chemosensitivity are important for experiments evaluating cancer therapies. The Scepter 2.0 cell counter, an automated handheld device based on the Coulter principle of impedance-based particle detection, enables the accurate discrimination of cell populations according to cell size and volume. In this study, the effects of SN-38, the active metabolite of irinotecan, on the colon cancermore » cell lines HCT116 and HT29 were evaluated using this device. The cell count data obtained with the Scepter counter were compared with those obtained with the {sup 3}H-thymidine uptake assay, which has been used to measure cell proliferation in many previous studies. In addition, we examined whether the changes in the size distributions of these cells reflected alterations in the frequency of cell cycle arrest and/or apoptosis induced by SN-38 treatment. In our experiments using the Scepter 2.0 cell counter, the cell counts were demonstrated to be accurate and reproducible measure and alterations of cell diameter reflected G2/M cell cycle arrest and apoptosis. Our data show that easy-to-use cell counting tools can be utilized to evaluate the cell-killing effects of novel treatments on cancer cells in vitro.« less

Flavopiridol induces apoptosis in glioma cell lines independent of retinoblastoma and p53 tumor suppressor pathway alterations by a caspase-independent pathway.

PubMed

Alonso, Michelle; Tamasdan, Cristina; Miller, Douglas C; Newcomb, Elizabeth W

2003-02-01

Flavopiridol is a synthetic flavone, which inhibits growth in vitro and in vivo of several solid malignancies such as renal, prostate, and colon cancers. It is a potent cyclin-dependent kinase inhibitor presently in clinical trials. In this study, we examined the effect of flavopiridol on a panel of glioma cell lines having different genetic profiles: five of six have codeletion of p16(INK4a) and p14(ARF); three of six have p53 mutations; and one of six shows overexpression of mouse double minute-2 (MDM2) protein. Independent of retinoblastoma and p53 tumor suppressor pathway alterations, flavopiridol induced apoptosis in all cell lines but through a caspase-independent mechanism. No cleavage products for caspase 3 or its substrate poly(ADP-ribose) polymerase or caspase 8 were detected. The pan-caspase inhibitor Z-VAD-fmk did not inhibit flavopiridol-induced apoptosis. Mitochondrial damage measured by cytochrome c release and transmission electron microscopy was not observed in drug-treated glioma cells. In contrast, flavopiridol treatment induced translocation of apoptosis-inducing factor from the mitochondria to the nucleus. The proteins cyclin D(1) and MDM2 involved in the regulation of retinoblastoma and p53 activity, respectively, were down-regulated early after flavopiridol treatment. Given that MDM2 protein can confer oncogenic properties under certain circumstances, loss of MDM2 expression in tumor cells could promote increased chemosensitivity. After drug treatment, a low Bcl-2/Bax ratio was observed, a condition that may favor apoptosis. Taken together, the data indicate that flavopiridol has activity against glioma cell lines in vitro and should be considered for clinical development in the treatment of glioblastoma multiforme.

Targeting Aurora Kinase with MK-0457 Inhibits Ovarian Cancer Growth

PubMed Central

Lin, Yvonne G.; Immaneni, Anand; Merritt, William M.; Mangala, Lingegowda S.; Kim, SeungWook; Shahzad, Mian M.K.; Tsang, Yvonne T.M.; Armaiz-Pena, Guillermo N.; Lu, Chunhua; Kamat, Aparna A.; Han, Liz Y.; Spannuth, WhitneyA.; Nick, Alpa M.; Landen, Charles N.; Wong, Kwong K.; Gray, Michael J.; Coleman, Robert L.; Bodurka, Diane C.; Brinkley, William R.; Sood, Anil K.

2009-01-01

Purpose The Aurora kinase family plays pivotal roles in mitotic integrity and cell cycle.We sought to determine the effects of inhibiting Aurora kinase on ovarian cancer growth in an orthotopic mouse model using a small molecule pan-Aurora kinase inhibitor, MK-0457. Experimental Design We examined cell cycle regulatory effects and ascertained the therapeutic efficacy of Aurora kinase inhibition both alone and combined with docetaxel using both in vitro and in vivo ovarian cancer models. Results In vitro cytotoxicity assays with HeyA8 and SKOV3ip1 cells revealed >10-fold greater docetaxel cytotoxicity in combination with MK-0457. After in vivo dose kinetics were determined using phospho-histone H3 status, therapy experiments with the chemosensitive HeyA8 and SKOV3ip1as well as the chemoresistant HeyA8-MDR and A2780-CP20 models showed that Aurora kinase inhibition alone significantly reduced tumor burden compared with controls (P values < 0.01). Combination treatment with docetaxel resulted in significantly improved reduction in tumor growth beyond that afforded by docetaxel alone (P ≤ 0.03). Proliferating cell nuclear antigen immunohistochemistry revealed that MK-0457 alone and in combination with docetaxel significantly reduced cellular proliferation (P values < 0.001). Compared with controls, treatment with MK-0457 alone and in combination with docetaxel also significantly increased tumor cell apoptosis by ∼3-fold (P < 0.01). Remarkably, compared with docetaxel monotherapy, MK-0457 combined with docetaxel resulted in significantly increased tumor cell apoptosis. Conclusions Aurora kinase inhibition significantly reduces tumor burden and cell proliferation and increases tumor cell apoptosis in this preclinical orthotopic model of ovarian cancer. The role of Aurora kinase inhibition in ovarian cancer merits further investigation in clinical trials. PMID:18765535

microRNA-137 modulates pancreatic cancer cells tumor growth, invasion and sensitivity to chemotherapy

PubMed Central

Xiao, Jie; Peng, Feng; Yu, Chao; Wang, Min; Li, Xu; Li, Zhipeng; Jiang, Jianxin; Sun, Chengyi

2014-01-01

Background: We intended to investigate the role of microRNA 137 (miR-137) in regulating pancreatic cancer cells’ growth in vitro and tumor development in vivo. Methods: QTR-PCR was used to examine the expression of miR-137 in pancreatic cancer cell lines and tumor cells from human patients. Lentivirual vector containing miR-137 mimic was used to overexpress miR-137 in PANC-1 and MIA PaCa-2 cells. The effects of overexpressing miR-137 on pancreatic cancer cell invasion and chemo-sensitivity to 5-fluorouracil (5-FU) were examined by cell migration and survival essays in vitro. The molecular target of miR-137, pleiotropic growth factor (PTN), was down-regulated by siRNA to examine its effects on cancer cell invasion. MIA PaCa-2 cells with endogenously overexpressed miR-137 were transplanted into null mice to examine tumor growth in vivo. Results: We found miR-137 was markedly underexpressed in both pancreatic cancer cell lines and tumor cells from patients. In cancer cells, transfection of lentivirus containing miR-137 mimic was able to markedly upregulate endogenous expression of miR-137, inhibited cancer cell invasion and increased sensitivities to chemotherapy reagent 5-FU. PTN was significantly down-regulated by overexpressing miR-137 in pancreatic cancer cells, and knocking down PTN was effective to rescue the reduced cancer cell invasion ability caused by miR-137 overexpression. More importantly, overexpressing miR-137 led to significant inhibition on tumor formation, including reductions in tumor weight and tumor size in vivo. Conclusion: Our study demonstrated that miR-137 played an important role in pancreatic cancer development. It may become a new therapeutic target for gene therapy in patients suffered from pancreatic cancer. PMID:25550779

The multidrug transporter ABCG2 (BCRP) is inhibited by plant-derived cannabinoids

PubMed Central

Holland, M L; Lau, D T T; Allen, J D; Arnold, J C

2007-01-01

Background and purpose: Cannabinoids are used therapeutically for the palliation of the adverse side effects associated with cancer chemotherapy. However, cannabinoids also inhibit both the activity and expression of the multidrug transporter, P-glycoprotein in vitro. Here we address the interaction of cannabinol (CBN), cannabidiol (CBD) and Δ9-tetrahydrocannabinol (THC) with the related multidrug transporter, ABCG2. Experimental approach: Cannabinoid inhibition of Abcg2/ABCG2 was assessed using flow cytometric analysis of substrate accumulation and ATPase activity assays. The cytotoxicity and chemosensitization by cannabinoids was determined with cell viability assays. Expression of cannabinoid and vanilloid receptors was assessed using reverse transcriptase polymerase chain reaction, and cannabinoid modulation of ABCG2 expression was examined using immunoblotting. Key results: CBN, CBD and THC increased the intracellular accumulation of the Abcg2/ABCG2 substrate, mitoxantrone, in an over-expressing cell line. The THC metabolite, (−)-11-nor-9-carboxy-Δ9-THC was much less potent. The plant cannabinoids inhibited both basal and substrate stimulated ATPase activity of human ABCG2. Cannabinoid cytotoxicity occurred in the absence of known cannabinoid cell surface receptors, and only at concentrations higher than those required for Abcg2/ABCG2 inhibition. Sub-toxic concentrations of the cannabinoids resensitized the overexpressing cell line to the cytotoxic effect of Abcg2/ABCG2 substrates, mitoxantrone and topotecan. This occurred in the absence of any effect on ABCG2 expression. Conclusions and implications: Cannabinoids are novel Abcg2/ABCG2 inhibitors, reversing the Abcg2-mediated multidrug-resistant phenotype in vitro. This finding may have implications for the co-administration of cannabinoids with pharmaceuticals that are ABCG2 substrates. PMID:17906686

Inhibition of Aurora A Kinase by Alisertib Induces Autophagy and Cell Cycle Arrest and Increases Chemosensitivity in Human Hepatocellular Carcinoma HepG2 Cells.

PubMed

Zhu, Qiaohua; Yu, Xinfa; Zhou, Zhi-Wei; Zhou, Chengyu; Chen, Xiao-Wu; Zhou, Shu-Feng

2017-01-01

Aurora A kinase represent a feasible target in cancer therapy. To evaluate the proteomic response of human liver carcinoma cells to alisertib (ALS) and identify the molecular targets of ALS, we examined the effects of ALS on the proliferation, cell cycle, autophagy, apoptosis, and chemosensitivity in HepG2 cells. The stable-isotope labeling by amino acids in cell culture (SILAC) based quantitative proteomic study was performed to evaluate the proteomic response to ALS. Cell cycle distribution and apoptosis were assessed using flow cytometry and autophagy was determined using flow cytometry and confocal microscopy. Our SILAC proteomic study showed that ALS regulated the expression of 914 proteins, with 407 molecules being up-regulated and 507 molecules being down-regulated in HepG2 cells. Ingenuity pathway analysis (IPA) and KEGG pathway analysis identified 146 and 32 signaling pathways were regulated by ALS, respectively, which were associated with cell survival, programmed cell death, and nutrition-energy metabolism. Subsequently, the verification experiments showed that ALS remarkably arrested HepG2 cells in G2/M phase and led to an accumulation of aneuploidy via regulating the expression of key cell cycle regulators. ALS induced a marked autophagy in a concentration- and time-dependent manner via the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt)/mammalian target of rapamycin (mTOR) signaling pathway. Autophagy inhibition promoted the pro-apoptotic effect of ALS, indicating a cyto-protective role of ALS-induced autophagy. ALS increased the chemosensitivity of HepG2 cells to cisplatin and doxorubicin. Taken together, ALS induces autophagy and cell cycle arrest in HepG2 cells via PI3K/Akt/mTOR-mediated pathway. Autophagy inhibition may promote the anticancer effect of ALS and sensitize the chemotherapy in HepG2 cells. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Networking of differentially expressed genes in human cancer cells resistant to methotrexate

PubMed Central

2009-01-01

Background The need for an integrated view of data obtained from high-throughput technologies gave rise to network analyses. These are especially useful to rationalize how external perturbations propagate through the expression of genes. To address this issue in the case of drug resistance, we constructed biological association networks of genes differentially expressed in cell lines resistant to methotrexate (MTX). Methods Seven cell lines representative of different types of cancer, including colon cancer (HT29 and Caco2), breast cancer (MCF-7 and MDA-MB-468), pancreatic cancer (MIA PaCa-2), erythroblastic leukemia (K562) and osteosarcoma (Saos-2), were used. The differential expression pattern between sensitive and MTX-resistant cells was determined by whole human genome microarrays and analyzed with the GeneSpring GX software package. Genes deregulated in common between the different cancer cell lines served to generate biological association networks using the Pathway Architect software. Results Dikkopf homolog-1 (DKK1) is a highly interconnected node in the network generated with genes in common between the two colon cancer cell lines, and functional validations of this target using small interfering RNAs (siRNAs) showed a chemosensitization toward MTX. Members of the UDP-glucuronosyltransferase 1A (UGT1A) family formed a network of genes differentially expressed in the two breast cancer cell lines. siRNA treatment against UGT1A also showed an increase in MTX sensitivity. Eukaryotic translation elongation factor 1 alpha 1 (EEF1A1) was overexpressed among the pancreatic cancer, leukemia and osteosarcoma cell lines, and siRNA treatment against EEF1A1 produced a chemosensitization toward MTX. Conclusions Biological association networks identified DKK1, UGT1As and EEF1A1 as important gene nodes in MTX-resistance. Treatments using siRNA technology against these three genes showed chemosensitization toward MTX. PMID:19732436

Chemosensitizing effects of carbon-based nanomaterials in cancer cells: enhanced apoptosis and inhibition of proliferation as underlying mechanisms

NASA Astrophysics Data System (ADS)

Erdmann, Kati; Ringel, Jessica; Hampel, Silke; Rieger, Christiane; Huebner, Doreen; Wirth, Manfred P.; Fuessel, Susanne

2014-10-01

Recent studies have shown that carbon nanomaterials such as carbon nanofibres (CNFs) and multi-walled carbon nanotubes (CNTs) can exert antitumor activities themselves and sensitize cancer cells to conventional chemotherapeutics such as carboplatin and cisplatin. In the present study, the chemosensitizing effect of CNFs and CNTs on cancer cells of urological origin was investigated regarding the underlying mechanisms. Prostate cancer (DU-145, PC-3) and bladder cancer (EJ28) cells were treated with carbon nanomaterials (CNFs, CNTs) and chemotherapeutics (carboplatin, cisplatin) alone as well as in combination for 24 h. Forty-eight (EJ28) or 72 h (DU-145, PC-3) after the end of treatment the effects on cellular proliferation, clonogenic survival, cell death rate and cell cycle distribution were evaluated. Depending on the cell line, simultaneous administration of chemotherapeutics and carbon nanomaterials produced an additional inhibition of cellular proliferation and clonogenic survival of up to 77% and 98%, respectively, compared to the inhibitory effects of the chemotherapeutics alone. These strongly enhanced antiproliferative effects were accompanied by an elevated cell death rate, which was predominantly mediated via apoptosis and not by necrosis. The antitumor effects of combinations with CNTs were less pronounced than those with CNFs. The enhanced effects of the combinatory treatments on cellular function were mostly of additive to partly synergistic nature. Furthermore, cell cycle analysis demonstrated an arrest at the G2/M phase mediated by a monotreatment with chemotherapeutics. Following combinatory treatments, mostly less than or nearly additive increases of cell fractions in the G2/M phase could be observed. In conclusion, the pronounced chemosensitizing effects of CNFs and CNTs were mediated by an enhanced apoptosis and inhibition of proliferation. The combination of carbon-based nanomaterials and conventional chemotherapeutics represents a novel approach in cancer therapy to bypass chemoresistance by minimizing the chemotherapeutic dosing.

Non-chemosensitive parafacial neurons simultaneously regulate active expiration and airway patency under hypercapnia in rats.

PubMed

de Britto, Alan A; Moraes, Davi J A

2017-03-15

Hypercapnia or parafacial respiratory group (pFRG) disinhibition at normocapnia evokes active expiration in rats by recruitment of pFRG late-expiratory (late-E) neurons. We show that hypercapnia simultaneously evoked active expiration and exaggerated glottal dilatation by late-E synaptic excitation of abdominal, hypoglossal and laryngeal motoneurons. Simultaneous rhythmic expiratory activity in previously silent pFRG late-E neurons, which did not express the marker of ventral medullary CO 2 -sensitive neurons (transcription factor Phox2b), was also evoked by hypercapnia. Hypercapnia-evoked active expiration, neural and neuronal late-E activities were eliminated by pFRG inhibition, but not after blockade of synaptic excitation. Hypercapnia produces disinhibition of non-chemosensitive pFRG late-E neurons to evoke active expiration and concomitant cranial motor respiratory responses controlling the oropharyngeal and upper airway patency. Hypercapnia produces active expiration in rats and the recruitment of late-expiratory (late-E) neurons located in the parafacial respiratory group (pFRG) of the ventral medullary brainstem. We tested the hypothesis that hypercapnia produces active expiration and concomitant cranial respiratory motor responses controlling the oropharyngeal and upper airway patency by disinhibition of pFRG late-E neurons, but not via synaptic excitation. Phrenic nerve, abdominal nerve (AbN), cranial respiratory motor nerves, subglottal pressure, and medullary and spinal neurons/motoneurons were recorded in in situ preparations of juvenile rats. Hypercapnia evoked AbN active expiration, exaggerated late-E discharges in cranial respiratory motor outflows, and glottal dilatation via late-E synaptic excitation of abdominal, hypoglossal and laryngeal motoneurons. Simultaneous rhythmic late-E activity in previously silent pFRG neurons, which did not express the marker of ventral medullary CO 2 -sensitive neurons (transcription factor Phox2b), was also evoked by hypercapnia. In addition, hypercapnia-evoked AbN active expiration, neural and neuronal late-E activities were eliminated by pFRG inhibition, but not after blockade of synaptic excitation. On the other hand, pFRG inhibition did not affect either hypercapnia-induced inspiratory increases in respiratory motor outflows or CO 2 sensitivity of the more medial Phox2b-positive neurons in the retrotrapezoid nucleus (RTN). Our data suggest that neither RTN Phox2b-positive nor other CO 2 -sensitive brainstem neurons activate Phox2b-negative pFRG late-E neurons under hypercapnia to produce AbN active expiration and concomitant cranial motor respiratory responses controlling the oropharyngeal and upper airway patency. Hypercapnia produces disinhibition of non-chemosensitive pFRG late-E neurons in in situ preparations of juvenile rats to activate abdominal, hypoglossal and laryngeal motoneurons. © 2016 The Authors. The Journal of Physiology © 2016 The Physiological Society.

The significance of G-CSF expression and myeloid-derived suppressor cells in the chemoresistance of uterine cervical cancer.

PubMed

Kawano, Mahiru; Mabuchi, Seiji; Matsumoto, Yuri; Sasano, Tomoyuki; Takahashi, Ryoko; Kuroda, Hiromasa; Kozasa, Katsumi; Hashimoto, Kae; Isobe, Aki; Sawada, Kenjiro; Hamasaki, Toshimitsu; Morii, Eiichi; Kimura, Tadashi

2015-12-15

Granulocyte-colony stimulating factor (G-CSF) producing malignant tumor has been reported to occur in various organs, and has been associated with poor clinical outcome. The aim of this study is to investigate the significance of tumor G-CSF expression in the chemosensitivity of uterine cervical cancer. The clinical data of recurrent or advanced cervical cancer patients who were treated with platinum-based chemotherapy were analyzed. Clinical samples, cervical cancer cell lines, and a mouse model of cervical cancer were employed to examine the mechanisms responsible for the development of chemoresistance in G-CSF-producing cervical cancer, focusing on myeloid-derived suppressor cells (MDSC). As a result, the tumor G-CSF expression was significantly associated with increased MDSC frequencies and compromised survival. In vitro and in vivo experiments demonstrated that the increased MDSC induced by tumor-derived G-CSF is involved in the development of chemoresistance. The depletion of MDSC via splenectomy or the administration of anti-Gr-1 antibody sensitized G-CSF-producing cervical cancer to cisplatin. In conclusion, tumor G-CSF expression is an indicator of an extremely poor prognosis in cervical cancer patients that are treated with chemotherapy. Combining MDSC-targeting treatments with current standard chemotherapies might have therapeutic efficacy as a treatment for G-CSF-producing cervical cancer.

Olfactory granule cell development in normal and hyperthyroid rats.

PubMed

Brunjes, P C; Schwark, H D; Greenough, W T

1982-10-01

Dendritic development was examined in olfactory bulbs of both normal 7-, 14-, 21- and 60-day-old rats and littermates treated on postnatal days 1-4 with 1 microgram/g body weight of L-thyroxine sodium. Tissue was processed via the Golgi-Cox technique and subjected to quantitative analyses of mitral and internal layer granule cell development. These populations of granule cells were selected because their pattern of late proliferation suggested potentially greater susceptibility to postnatal hormonal alterations. Although neonatal hyperthyroidism induces widespread acceleration of maturation, including precocious chemosensitivity, granule cell development was unaffected relative to littermate controls. Both normal and hyperthyroid groups exhibited an inverted U-shaped pattern of cellular development, with rapid dendritic dendritic growth and expansion occurring during the earliest ages tested, but with loss of processes and dendritic field size occurring after day 21.

Life-Threatening Opioid Toxicity

DTIC Science & Technology

1987-01-01

mu recep- Fentanyl (Sublimaze) tor has been determined to mediate analgesia Propoxyphene (Darvon) and ventilatory depre.;sion. Furthermore, it Pure...following opioid overdose . The reduction in ventilation is accompanied by Opioids produce their major effect on the a decreased chemosensitivity to...opiates a o d F Diphenoxylate (active ingredient in Lomotil)a mperidline overdose . Fuithermore, ven- rpxhe (avnmepedinePropoxyphene Darvon) titatory

Chemical sensors for breath gas analysis: the latest developments at the Breath Analysis Summit 2013.

PubMed

Tisch, Ulrike; Haick, Hossam

2014-06-01

Profiling the body chemistry by means of volatile organic compounds (VOCs) in the breath opens exciting new avenues in medical diagnostics. Gas sensors could provide ideal platforms for realizing portable, hand-held breath testing devices in the near future. This review summarizes the latest developments and applications in the field of chemical sensors for diagnostic breath testing that were presented at the Breath Analysis Summit 2013 in Wallerfangen, Germany. Considerable progress has been made towards clinically applicable breath testing devices, especially by utilizing chemo-sensitive nanomaterials. Examples of several specialized breath testing applications are presented that are either based on stand-alone nanomaterial-based sensors being highly sensitive and specific to individual breath compounds over others, or on combinations of several highly specific sensors, or on experimental nanomaterial-based sensors arrays. Other interesting approaches include the adaption of a commercially available MOx-based sensor array to indirect breath testing applications, using a sample pre-concentration method, and the development of compact integrated GC-sensor systems. The recent trend towards device integration has led to the development of fully integrated prototypes of point-of-care devices. We describe and compare the performance of several prototypes that are based on different sensing technologies and evaluate their potential as low-cost and readily available next-generation medical devices.

Evaluation of Altered Stromal/Epithelial Tissue Arrangement of the c-Kit Messaging System in the Control of Breast Cancer

DTIC Science & Technology

2008-07-31

Lipofectamine-mediated transfection of pcDNA3/c-Kit. Chemosensitivity to the c-Kit modulating drugs, imatinib and alpha - fetoprotein -derived peptide (AFPep), was...Cancer Res. 10:3528-3534. 7. Bennett JA, Mesfin FB, Andersen TT, Gierthy JF, and Jacobson HI. (2002). A peptide derived from α- fetoprotein prevents

Dacarbazine promotes stromal remodeling and lymphocyte infiltration in cutaneous melanoma lesions.

PubMed

Nardin, Alessandra; Wong, Wing-Cheong; Tow, Charlene; Molina, Thierry Jo; Tissier, Frédérique; Audebourg, Anne; Garcette, Marylene; Caignard, Anne; Avril, Marie-Francoise; Abastado, Jean-Pierre; Prévost-Blondel, Armelle

2011-09-01

Dacarbazine (DTIC) is the standard first-line drug for advanced stage melanoma, but it induces objective clinical responses in only 15% of patients. This study was designed to identify molecular changes specifically induced by treatment in chemo-sensitive lesions. Using global transcriptome analysis and immunohistochemistry, we analyzed cutaneous metastases resected from patients with melanoma before and after DTIC treatment. The treatment induced similar functional changes in different lesions from the same patient. Stromal and immune response-related genes were the most frequently upregulated, particularly in lesions that responded to treatment by stabilizing or regressing. T-cell infiltration and enhanced major histocompatibility complex class II expression were observed in a subset of patients. Stable, chemo-sensitive lesions exhibited activation of genetic programs related to extracellular matrix remodeling, including increased expression of secreted protein acidic and rich in cysteine (SPARC) by tumor cells. These events were associated with local response to treatment and with superior survival in our group of patients. In contrast, SPARC expression was downregulated in lesions resistant to DTIC. Thus, chemotherapy drugs originally selected for their direct cytotoxicity to tumor cells may also influence disease progression by inducing changes in the tumor microenvironment.

Intensified chemotherapy with stem-cell rescue in germ-cell tumors.

PubMed

Simonelli, M; Rosti, G; Banna, G L; Pedrazzoli, P

2012-04-01

Based on the high chemosensitivity of germ-cell tumors (GCTs), the concept of high-dose chemotherapy (HDCT) has been developed worldwide and investigated through many clinical trials. It has been carried out in different clinical settings, ranging from resistant or absolute refractory disease to chemosensitive relapse. HDCT with stem-cell support has been also explored as a part of first-line strategy for poor-prognosis patients. Our review summarized results from clinical trials evaluating the role of HDCT in patients with advanced GCTs. So far available data were obtained through a Medline search of English-language literature. Several phase II trials and retrospective series have shown a possible benefit for GCT patients with recurrent disease as well as in first-line setting. Despite these results, data derived from randomized phase III studies failed to demonstrate any survival advantage for HDCT over conventional chemotherapy. The role of HDCT in GCTs remains controversial. We need new prospective studies based on prognostic factors with multiple transplants of carboplatin and etoposide as the preferred high dose regimen. At present, based mainly on retrospective and phase II studies, HDCT may represent a therapeutic option for patients with primary refractory disease or for those with a second or further relapse.

Curcumin-enhanced chemosensitivity of FDA-approved platinum (II)-based anti-cancer drugs involves downregulation of nuclear endonuclease G and NF-κB as well as induction of apoptosis and G2/M arrest.

PubMed

Wang, Ying-Ti; Liu, Hsiao-Sheng; Su, Chun-Li

2014-05-01

Curcumin, an active natural compound in turmeric and curry, has been reported to exhibit anti-cancer effect. Cisplatin, carboplatin and oxaliplatin are used to treat various types of cancers. However, acquired resistance and toxicities are observed. Here, the addition of curcumin significantly increased cytotoxicity of the anti-cancer drugs on human colorectal cancer HT-29 cells, producing synergistic (cisplatin and carboplatin) and additivity (oxaliplatin) effects. Treatments in combination with curcumin resulted in a significantly increased induction of apoptosis and occurrence of G2/M arrest. Nuclear apoptosis-inducing factor (AIF), EndoG and NF-κB were elevated by anti-cancer drugs, suggesting the involvement of AIF and EndoG. The addition of curcumin suppressed nuclear AIF and EndoG and reversed anti-cancer drugs-induced NF-κB expression, suggesting the association of EndoG and NF-κB in curcumin-enhanced chemosensitivity. Therefore, the intake of foods rich in curcumin or curcumin-containing supplements should be taken into consideration for patients receiving chemotherapy to optimize the outcome of treatments.

Orotate phosphoribosyl transferase mRNA expression and the response of cholangiocarcinoma to 5-fluorouracil

PubMed Central

Hahnvajanawong, Chariya; Chaiyagool, Jariya; Seubwai, Wunchana; Bhudhisawasdi, Vajarabhongsa; Namwat, Nisana; Khuntikeo, Narong; Sripa, Banchob; Pugkhem, Ake; Tassaneeyakul, Wichittra

2012-01-01

AIM: To determine whether expression of certain enzymes related to 5-fluorouracil (5-FU) metabolism predicts 5-FU chemosensitivity in cholangiocarcinoma (CCA). METHODS: The histoculture drug response assay (HDRA) was performed using surgically resected CCA tissues. Tumor cell viability was determined morphologically with hematoxylin and eosin- and terminal deoxynucleotide transferase-mediated dUTP nick-end labeling-stained tissues. The mRNA expression of thymidine phosphorylase (TP), orotate phosphoribosyl transferase (OPRT), thymidylate synthase (TS), and dihydropyrimidine dehydrogenase (DPD) was determined with real-time reverse transcriptase-polymerase chain reaction. The levels of gene expression and the sensitivity to 5-FU were evaluated. RESULTS: Twenty-three CCA tissues were obtained from patients who had been diagnosed with intrahepatic CCA and who underwent surgical resection at Srinagarind Hospital, Khon Kaen University from 2007 to 2009. HDRA was used to determine the response of these CCA tissues to 5-FU. Based on the dose-response curve, 200 μg/mL 5-FU was selected as the test concentration. The percentage of inhibition index at the median point was selected as the cut-off point to differentiate the responding and non-responding tumors to 5-FU. When the relationship between TP, OPRT, TS and DPD mRNA expression levels and the sensitivity of CCA tissues to 5-FU was examined, only OPRT mRNA expression was significantly correlated with the response to 5-FU. The mean expression level of OPRT was significantly higher in the responder group compared to the non-responder group (0.41 ± 0.25 vs 0.22 ± 0.12, P < 0.05). CONCLUSION: OPRT mRNA expression may be a useful predictor of 5-FU chemosensitivity of CCA. Whether OPRT mRNA could be used to predict the success of 5-FU chemotherapy in CCA patients requires confirmation in patients. PMID:22912546

Characterization of the multixenobiotic resistance (MXR) mechanism in embryos and larvae of the zebra mussel (Dreissena polymorpha) and studies on its role in tolerance to single and mixture combinations of toxicants.

PubMed

Faria, Melissa; Navarro, Ana; Luckenbach, Till; Piña, Benjamin; Barata, Carlos

2011-01-17

The study of the cellular mechanisms of tolerance of organisms to pollution is a key issue in aquatic environmental risk assessment. Recent evidence indicates that multixenobiotic resistance (MXR) mechanisms represent a general biological defense of many marine and freshwater organisms against environmental toxicants. In this work, toxicologically relevant xenobiotic efflux transporters were studied in early life stages of zebra mussels (Dreissena polymorpha). Expression of a P-gp1 (ABCB1) transporter gene and its associated efflux activities during development were studied, using qRT-PCR and the fluorescent transporter substrates rhodamine B and calcein-AM combined with specific transporter inhibitors (chemosensitizers). Toxicity bioassays with the model P-gp1 chemotherapeutic drug vinblastine applied singly and in combination with different chemosensitizers were performed to elucidate the tolerance role of the P-gp1 efflux transporter. Results evidenced that the gene expression and associated efflux activities of ABC transporters were low or absent in eggs and increased significantly in 1-3d old trochophora and veliger larvae. Specific inhibitors of Pgp1 and/or MRP transport activities including cyclosporine A, MK571, verapamil and reversin 205 and the musk celestolide resulted in a concentration dependent inhibition of related transport activities in zebra mussel veliger larvae, with IC50 values in the lower micromolar range and similar to those reported for mammals, fish and mussels. Binary mixtures of the tested transporter inhibitors except celestolide with the anticancer drug and P-gp1 substrate vinblastine increased the toxicity of the former compound more than additively. These results indicate that MXR transporter activity is high in early life-stages of the zebra mussel and that may play an important role in the tolerance to environmental contaminants. Copyright © 2010 Elsevier B.V. All rights reserved.

[A prospective study of adenosine triphosphate-tumor chemosensitivity assay directed chemotherapy in patients with recurrent ovarian cancer].

PubMed

Gao, Yu-tao; Wu, Ling-ying; Zhang, Wei; Zhao, Dan; Li, Ning; Tian, Hai-mei; Wang, Xiao-bing; Li, Mo; Sun, Yang-chun; Li, Nan; Li, Xiao-guang

2013-05-01

To investigate the efficacy of adenosine triphosphate (ATP)-tumor chemosensitivity assay (TCA) directed chemotherapy in patients with recurrent epithelial ovarian cancer. From August 2010 to June 2012, recurrent epithelial ovarian cancer patients were prospectively enrollmented in Cancer Hospital, Peking Union Medical College,Chinese Academy of Medical Sciences.The entry criteria are as follows: (1) Histologically proven to be epithelial ovarian cancer. (2) Patients of recurrent ovarian cancer with bidimensionally measurable tumor, or ascitic or pleural fluid for testing. (3) Karnofsky performance status > 60. (4) A life expectancy of at least more than 6 months.According to patients desires, they were assigned into two groups: assay-directed therapy group and physician's-choice therapy group, patients' clinical and pathological characteristics, response rate to chemotherapy and progression-free survival (PFS) were compared between two groups. A total of 113 patients with recurrent epithelial ovarian cancer were prospectively enrollmented to assay-directed chemotherapy (n = 56) or physician's-choice chemotherapy (n = 57).There was no difference in median age,types of recurrence, surgical-pathological stage, pathological type, tumor grade, times of recurrence, residual disease at secondary cytoreductive surgery between assay-directed group and physician's-choice group. The overall response rate (ORR) and median PFS in the ATP-TCA group was 66% (37/56) and 7 months, while the ORR in the control group was 46% (26/57, P = 0.037), the median PFS was 4 months (P = 0.040). For platinum-resistant patients, the ORR between ATP-TCA directed chemotherapy 59% (16/27) and control group 25% (7/28) were significantly different (P = 0.010), and the median PFS between two groups were also significantly different (5 months and 2 months, respectively, P = 0.003). ATP-TCA directed chemotherapy could improve ORR and PFS in patients with recurrent epithelial ovarian cancer, especially in platinum-resistant patients.

Curcumin-albumin conjugates as an effective anti-cancer agent with immunomodulatory properties.

PubMed

Aravind, S R; Krishnan, Lissy K

2016-05-01

Curcumin (diferuloylmethane) is an active ingredient in turmeric (Curcuma longa) with anti-inflammatory, antioxidant, chemopreventive, chemosensitization, and radiosensitization properties. Conjugation of curcumin (Curc) to albumin (Alb) has been found to increase the aqueous solubility of the drug. The current study aimed to prove the safe use of the Curc-Alb conjugate in animals and to demonstrate that it retains drug action both in vitro and in vivo. Dalton's lymphoma ascites (DLA) cell viability was inhibited by the Curc-Alb conjugate in a dose dependent manner in vitro, as evidenced by the MTT assay. Administration of up to 11.4 mg of conjugated curcumin per kg body weight to healthy animals was non-toxic both in terms of lethality and weight loss. Histological analysis of vital organs (kidney, liver and spleen) also did not show toxic effects. Favorable immuno-modulatory activity was observed after continuous administration of sub-acute doses of the conjugate which caused increase in total leukocyte count, platelet count, and viable cell count in bone marrow, and enhanced proliferation of lymphocyte in vitro upon culture. In vivo studies in the DLA tumor model in mice demonstrated that conjugated drug induces tumor reduction and prevention. Significant tumor reduction was observed when the Curc-Alb conjugate was administered intraperitoneally in DLA-induced mice after 1 day (prevention therapy) and 7 days (reduction therapy) of tumor induction. There was significant reduction in both tumor volume and tumor cell numbers in the treated animals as well as a marked increase in their mean survival time and percent increase in life span. The effect was greater when the conjugate was administered soon after inducing the tumor as compared to when treatment was started after allowing tumor to grow for 7 days. Thus, the results of the present study suggest that curcumin albumin conjugate has immunomodulatory and tumor growth inhibition properties. The study postulates the drug form has the potential to be used as an anticancer agent in affected human subjects. Copyright © 2016 Elsevier B.V. All rights reserved.

Overexpression of RBM5 induces autophagy in human lung adenocarcinoma cells.

PubMed

Su, Zhenzhong; Wang, Ke; Li, Ranwei; Yin, Jinzhi; Hao, Yuqiu; Lv, Xuejiao; Li, Junyao; Zhao, Lijing; Du, Yanwei; Li, Ping; Zhang, Jie

2016-02-29

Dysfunctions in autophagy and apoptosis are closely interacted and play an important role in cancer development. RNA binding motif 5 (RBM5) is a tumor suppressor gene, which inhibits tumor cells' growth and enhances chemosensitivity through inducing apoptosis in our previous studies. In this study, we investigated the relationship between RBM5 overexpression and autophagy in human lung adenocarcinoma cells. Human lung adenocarcinoma cancer (A549) cells were cultured in vitro and were transiently transfected with a RBM5 expressing plasmid (GV287-RBM5) or plasmid with scrambled control sequence. RBM5 expression was determined by semi-quantitative reverse transcription polymerase chain reaction (RT-PCR) and Western blot. Intracellular LC-3 I/II, Beclin-1, lysosome associated membrane protein-1 (LAMP1), Bcl-2, and NF-κB/p65 protein levels were detected by Western blot. Chemical staining with monodansylcadaverine (MDC) and acridine orange (AO) was applied to detect acidic vesicular organelles (AVOs). The ultrastructure changes were observed under transmission electron microscope (TEM). Then, transplanted tumor models of A549 cells on BALB/c nude mice were established and treated with the recombinant plasmids carried by attenuated Salmonella to induce RBM5 overexpression in tumor tissues. RBM5, LC-3, LAMP1, and Beclin1 expression was determined by immunohistochemistry staining in plasmids-treated A549 xenografts. Our study demonstrated that overexpression of RBM5 caused an increase in the autophagy-related proteins including LC3-I, LC3-II, LC3-II/LC3-I ratio, Beclin1, and LAMP1 in A549 cells. A large number of autophagosomes with double-membrane structure and AVOs were detected in the cytoplasm of A549 cells transfected with GV287-RBM5 at 24 h. We observed that the protein level of NF-κB/P65 was increased and the protein level of Bcl-2 decreased by RBM5 overexpression. Furthermore, treatment with an autophagy inhibitor, 3-MA, enhanced RBM5-induced cell death and chemosensitivity in A549 cells. Furthermore, we successfully established the lung adenocarcinoma animal model using A549 cells. Overexpression of RBM5 enhanced the LC-3, LAMP1, and Beclin1 expression in the A549 xenografts. Our findings showed for the first time that RBM5 overexpression induced autophagy in human lung adenocarcinoma cells, which might be driven by upregulation of Beclin1, NF-κB/P65, and downregulation of Bcl-2. RBM5-enhanced autophagy acts in a cytoprotective way and inhibition of autophagy may improve the anti-tumor efficacy of RBM5 in lung cancer.

Differential chemosensory feeding behaviour by three co-occurring mysids (Crustacea, Mysidacea) from southeastern Tasmania.

PubMed

Metillo, Ephrime B; Ritz, David A

2003-02-01

Three mysid species showed differences in chemosensory feeding as judged from stereotyped food capturing responses to dissolved mixtures of feeding stimulant (either betaine-HCl or glycine) and suppressant (ammonium). The strongest responses were to 50:50 mixtures of both betaine-ammonium and glycine-ammonium solutions. In general, the response curve to the different mixtures tested was bell-shaped. Anisomysis mixta australis only showed the normal curve in response to the glycine-ammonium mixture. The platykurtic curve for Tenagomysis tasmaniae suggests a less optimal response to the betaine-HCl-ammonium solution. Paramesopodopsis rufa reacted more strongly to the betaine-ammonium than to the glycine-ammonium solutions, and more individuals of this species responded to both solutions than the other two species. It is suggested that these contrasting chemosensitivities of the three coexisting mysid species serve as a means of partitioning the feeding niche.

[X-linked inhibitor of apoptosis protein (XIAP) and Survivin suppression on human pancreatic cancer cells Panc-1 proliferation and chemosensitivety].

PubMed

Zai, Hong-yan; Yi, Xiao-ping; Li, Yi-xiong; You, Xue-ying; Cao, Li-ping; Liu, Hui

2013-04-18

To investigate the effect on cell proliferation and chemosensitivity of human pancreatic cancer cells Panc-1 after X-linked inhibitor of apoptosis protein (XIAP) and Survivin are inhibited simultaneously, and to compare it with the separate gene suppression strategy by which expression of XIAP or Survivin is inhibited respectively. Panc-1 (Panc-1-X, Panc-1-S and Panc-1-XS) in which expression of XIAP and/or Survivin was inhibited, was established by using XIAP-shRNA lentiviral and Survivin-shRNA lentiviral we had built. The expressions of XIAP and Survivin mRNA and protein were evaluated by Real-time PCR and Semi-quantitatively Western blot analysis; cell proliferation was investigated by cell counting and colony formation assay; cell apoptosis was investigated by Caspase-3/7 activity assay kit and flow cytometry; gemcitabine (Gem) chemosensitivity was investigated by MTT assay. The pancreatic cell line Panc-1 in which the expression of XIAP and/or Survivin was stablely inhibited was successfully established. The cell proliferation of Panc-1-XS cells decreased significantly. The colony formation rate of Panc-1-XS cells (10.12%± 1.33%), was significantly lower than that of Panc-1-XncSnc cells (96.61% ± 7.89%) and Panc-1 cells (100.28% ± 8.97%) respectively (P<0.05). After being treated by 0.5 mg/L Gem for 24 h, the Caspase-3/7 relative activity of Panc-1-XS cells (15.02 ± 0.57) was significantly higher than that of Panc-1 cells and Panc-1-XncSnc cells (8.87 ± 0.19 and 9.05 ± 0.23, respectively; P<0.05); and the rate of apoptosis of Panc-1-XS cells (24.09% ± 2.75%) was significantly higher than that of Panc-1-XncSnc cells and Panc-1 cells (12.09% ± 1.97% and 12.06% ± 1.22%, respectively; P<0.05). The IC50 value of Panc-1-XS cells [(0.47 ± 0.04) mg/L] was significantly lower than that of Panc-1-XncSnc cells [(2.18 ± 0.13) mg/L] and Panc-1 cells [(2.13 ± 0.18) mg/L, P<0.05]. Further testing also showed that, the IC50 value of Panc-1-XS cells [(0.47 ± 0.04) mg/L] was significantly lower than that of Panc-1-X cells [(0.76 ± 0.07) mg/L] and Panc-1-S cells [(0.87 ± 0.09) mg/L, P<0.05]. The cell proliferation of Panc-1 cells was significantly suppressed and the Gem chemosensitivity was significantly enhanced after expressions of XIAP and Survivin were inhibited simultaneously, and significantly better than the strategy in which expressions of XIAP and Survivin were inhibited separately.

Megalin-Mediated Oligonucleotide Trafficking for Breast Cancer Chemosensitization

DTIC Science & Technology

2010-08-01

role of apoprotein J (clusterin) in atherogenesis: binding to enzymatically modified low- density lipoprotein reduces fatty acid-mediated cytotoxicity...therapeutics trafficking [1]. High megalin expression may reflect the level of chemoresistance of the cancer cells [2], while clusterin is known to cause...targeting moieties such as apolipoprotein E (Apo-E) [5] will enhance siRNA delivery into breast cancer cells which reportedly express high megalin level

Investigation of Particle Accumulation, Chemosensitivity and Thermosensitivity for Effective Solid Tumor Therapy Using Thermosensitive Liposomes and Hyperthermia.

PubMed

Lokerse, Wouter J M; Bolkestein, Michiel; Ten Hagen, Timo L M; de Jong, Marion; Eggermont, Alexander M M; Grüll, Holger; Koning, Gerben A

2016-01-01

Doxorubicin (Dox) loaded thermosensitive liposomes (TSLs) have shown promising results for hyperthermia-induced local drug delivery to solid tumors. Typically, the tumor is heated to hyperthermic temperatures (41-42 °C), which induced intravascular drug release from TSLs within the tumor tissue leading to high local drug concentrations (1-step delivery protocol). Next to providing a trigger for drug release, hyperthermia (HT) has been shown to be cytotoxic to tumor tissue, to enhance chemosensitivity and to increase particle extravasation from the vasculature into the tumor interstitial space. The latter can be exploited for a 2-step delivery protocol, where HT is applied prior to i.v. TSL injection to enhance tumor uptake, and after 4 hours waiting time for a second time to induce drug release. In this study, we compare the 1- and 2-step delivery protocols and investigate which factors are of importance for a therapeutic response. In murine B16 melanoma and BFS-1 sarcoma cell lines, HT induced an enhanced Dox uptake in 2D and 3D models, resulting in enhanced chemosensitivity. In vivo, therapeutic efficacy studies were performed for both tumor models, showing a therapeutic response for only the 1-step delivery protocol. SPECT/CT imaging allowed quantification of the liposomal accumulation in both tumor models at physiological temperatures and after a HT treatment. A simple two compartment model was used to derive respective rates for liposomal uptake, washout and retention, showing that the B16 model has a twofold higher liposomal uptake compared to the BFS-1 tumor. HT increases uptake and retention of liposomes in both tumors models by the same factor of 1.66 maintaining the absolute differences between the two models. Histology showed that HT induced apoptosis, blood vessel integrity and interstitial structures are important factors for TSL accumulation in the investigated tumor types. However, modeling data indicated that the intraliposomal Dox fraction did not reach therapeutic relevant concentrations in the tumor tissue in a 2-step delivery protocol due to the leaking of the drug from its liposomal carrier providing an explanation for the observed lack of efficacy.

Use of a combined effect model approach for discriminating between ABCB1- and ABCC1-type efflux activities in native bivalve gill tissue

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

Faria, Melissa; CESAM & Departamento de Biologia, Universidade de Aveiro, 3810-193 Aveiro; Pavlichenko, Vasiliy

Aquatic organisms, such as bivalves, employ ATP binding cassette (ABC) transporters for efflux of potentially toxic chemicals. Anthropogenic water contaminants can, as chemosensitizers, disrupt efflux transporter function enabling other, putatively toxic compounds to enter the organism. Applying rapid amplification of cDNA ends (RACE) PCR we identified complete cDNAs encoding ABCB1- and ABCC1-type transporter homologs from zebra mussel providing the molecular basis for expression of both transporter types in zebra mussel gills. Further, efflux activities of both transporter types in gills were indicated with dye accumulation assays where efflux of the dye calcein-am was sensitive to both ABCB1- (reversin 205, verapamil)more » and ABCC1- (MK571) type specific inhibitors. The assumption that different inhibitors targeted different efflux pump types was confirmed when comparing measured effects of binary inhibitor compound mixtures in dye accumulation assays with predictions from mixture effect models. Effects by the MK571/reversin 205 mixture corresponded better with independent action, whereas reversin 205/verapamil joint effects were better predicted by the concentration addition model indicating different and equal targets, respectively. The binary mixture approach was further applied to identify the efflux pump type targeted by environmentally relevant chemosensitizing compounds. Pentachlorophenol and musk ketone, which were selected after a pre-screen of twelve compounds that previously had been identified as chemosensitizers, showed mixture effects that corresponded better with concentration addition when combined with reversine 205 but with independent action predictions when combined with MK571 indicating targeting of an ABCB1-type efflux pump by these compounds. - Highlights: • Sequences and function of ABC efflux transporters in bivalve gills were explored. • Full length Dreissena polymorpha abcb1 and abcc1 cDNA sequences were identified. • A mixture effect design with inhibitors was applied in transporter activity assays. • ABCB1- and ABCC-type efflux activities were distinguished in native gill tissue. • Inhibitory action of environmental chemicals targeted ABCB1-type efflux activity.« less

The role of in vitro methods as alternatives to animals in toxicity testing.

PubMed

Anadón, Arturo; Martínez, María Aranzazu; Castellano, Victor; Martínez-Larrañaga, María Rosa

2014-01-01

It is accepted that animal testing should be reduced, refined or replaced as far as it is practicably possible. There are also a wide variety of in vitro models, which are used as screening studies and mechanistic investigations. The ability of an in vitro assay to be reliable, biomedically, is essential in pharmaceutical development. Furthermore, it is necessary that cells used in in vitro testing mimic the phenotype of cells within the human target tissue. The focus of this review article is to identify the key points of in vitro assays. In doing so, the authors take into account the chemical agents that are assessed and the integrated in vitro testing strategies. There is a transfer of toxicological data from primary in vivo animal studies to in vitro assays. The key element for designing an integrated in vitro testing strategy is summarized as follows: exposure modeling of chemical agents for in vitro testing; data gathering, sharing and read-across for testing a class of chemical; a battery of tests to assemble a broad spectrum of data on different mechanisms of action to predict toxic effects; and applicability of the test and the integrated in vitro testing strategies and flexibility to adjust the integrated in vitro testing strategies to test substance. While these methods will be invaluable if effective, more studies must be done to ensure reliability and suitability of these tests for humans.

Insulin-like growth factor-1 signaling in renal cell carcinoma.

PubMed

Tracz, Adam F; Szczylik, Cezary; Porta, Camillo; Czarnecka, Anna M

2016-07-12

Renal cell carcinoma (RCC) incidence is highest in highly developed countries and it is the seventh most common neoplasm diagnosed. RCC management include nephrectomy and targeted therapies. Type 1 insulin-like growth factor (IGF-1) pathway plays an important role in cell proliferation and apoptosis resistance. IGF-1 and insulin share overlapping downstream signaling pathways in normal and cancer cells. IGF-1 receptor (IGF1R) stimulation may promote malignant transformation promoting cell proliferation, dedifferentiation and inhibiting apoptosis. Clear cell renal cell carcinoma (ccRCC) patients with IGF1R overexpression have 70 % increased risk of death compared to patients who had tumors without IGF1R expression. IGF1R signaling deregulation may results in p53, WT, BRCA1, VHL loss of function. RCC cells with high expression of IGF1R are more resistant to chemotherapy than cells with low expression. Silencing of IGF1R increase the chemosensitivity of ccRCC cells and the effect is greater in VHL mutated cells. Understanding the role of IGF-1 signaling pathway in RCC may result in development of new targeted therapeutic interventions. First preclinical attempts with anti-IGF-1R monoclonal antibodies or fragment antigen-binding (Fab) fragments alone or in combination with an mTOR inhibitor were shown to inhibit in vitro growth and reduced the number of colonies formed by of RCC cells.

[High-dose chemotherapy as a strategy to overcome drug resistance in solid tumors].

PubMed

Selle, Frédéric; Gligorov, Joseph; Soares, Daniele G; Lotz, Jean-Pierre

2016-10-01

The concept of high-doses chemotherapy was developed in the 1980s based on in vitro scientific observations. Exposure of tumor cells to increasing concentrations of alkylating agents resulted in increased cell death in a strong dose-response manner. Moreover, the acquired resistance of tumor cells could be overcome by dose intensification. In clinic, dose intensification of alkylating agents resulted in increased therapeutic responses, however associated with significant hematological toxicity. Following the development of autologous stem cells transplantation harvesting from peripheral blood, the high-doses of chemotherapy, initially associated with marked toxic effects, could be more easily tolerated. As a result, the approach was evaluated in different types of solid tumors, including breast, ovarian and germ cell tumors, small cell lung carcinoma, soft tissue sarcomas and Ewing sarcoma. To date, high-doses chemotherapy with hematopoietic stem cells support is only used as a salvage therapy to treat poor prognosis germ cell tumors patients with chemo-sensitive disease. Regarding breast and ovarian cancer, high-doses chemotherapy should be considered only in the context of clinical trials. However, intensive therapy as an approach to overcome resistance to standard treatments is still relevant. Numerous efforts are still ongoing to identify novel therapeutic combinations and active treatments to improve patients' responses. Copyright © 2016 Société Française du Cancer. Published by Elsevier Masson SAS. All rights reserved.

A tumor-targeting p53 nanodelivery system limits chemoresistance to temozolomide prolonging survival in a mouse model of glioblastoma multiforme.

PubMed

Kim, Sang-Soo; Rait, Antonina; Kim, Eric; Pirollo, Kathleen F; Chang, Esther H

2015-02-01

Development of temozolomide (TMZ) resistance contributes to the poor prognosis for glioblastoma multiforme (GBM) patients. It was previously demonstrated that delivery of exogenous wild-type tumor suppressor gene p53 via a tumor-targeted nanocomplex (SGT-53) which crosses the blood-brain barrier could sensitize highly TMZ-resistant GBM tumors to TMZ. Here we assessed whether SGT-53 could inhibit development of TMZ resistance. SGT-53 significantly chemosensitized TMZ-sensitive human GBM cell lines (U87 and U251), in vitro and in vivo. Furthermore, in an intracranial GBM tumor model, two cycles of concurrent treatment with systemically administered SGT-53 and TMZ inhibited tumor growth, increased apoptosis and most importantly, significantly prolonged median survival. In contrast TMZ alone had no significant effect on median survival compared to a single cycle of TMZ. These results suggest that combining SGT-53 with TMZ appears to limit development of TMZ resistance, prolonging its anti-tumor effect and could be a more effective therapy for GBM. Using human glioblastoma multiforma cell lines, this research team demonstrated that the delivery of exogenous wild-type tumor suppressor gene p53 via a tumor-targeted nanocomplex limited the development of temozolomide resistance and prolonged its anti-tumor effect, which may enable future human application of this or similar techniques. Copyright © 2015 Elsevier Inc. All rights reserved.

USP22 knockdown enhanced chemosensitivity of hepatocellular carcinoma cells to 5-Fu by up-regulation of Smad4 and suppression of Akt

PubMed Central

Li, Jiazhi; Yang, Xiaozhou; Yin, Huimin; Xiao, Congshu; Sheng, Jie; Li, Yang; Tang, Bo; Li, Rongkuan

2017-01-01

USP22, a member of the deubiquitinases (DUBs) family, is known to be a key subunit of the human Spt-Ada-Gcn5 acetyltransferase (hSAGA) transcriptional cofactor complex. Within hSAGA, USP22 removes ubiquitin from histone proteins, thus regulating the transcription and expression of downstream genes. USP22 plays important roles in many cancers; however, its effect and the mechanism underlying HCC chemoresistance remain unclear. In the present study, we found that USP22 was highly expressed in chemoresistant HCC tissues and cells and was correlated with the prognosis of HCC patients who received chemotherapy. Silencing USP22 in chemoresistant HCC Bel/Fu cells dramatically inhibited proliferation, migration, invasion and epithelial-mesenchymal transition in vitro; suppressed tumorigenic and metastatic capacities in vivo; and inhibited drug resistance-related proteins (MDR1, LRP, MRP1). Mechanistically, we found that USP22 knockdown exerts its function through down-regulating PI3K and activating Smad4, which inhibited phosphorylation of Akt. Silencing Smad4 blocked USP22 knockdown-induced Akt inhibition in Bel/Fu cells. Our results, for the first time, provide evidence that USP22 plays a critical role in the development of chemoresistant HCC cells and that high USP22 expression serves as a molecular marker for the prognosis of HCC patients who undergo chemotherapy. PMID:28445968

USP22 knockdown enhanced chemosensitivity of hepatocellular carcinoma cells to 5-Fu by up-regulation of Smad4 and suppression of Akt.

PubMed

Zhang, Jing; Luo, Nan; Tian, Yu; Li, Jiazhi; Yang, Xiaozhou; Yin, Huimin; Xiao, Congshu; Sheng, Jie; Li, Yang; Tang, Bo; Li, Rongkuan

2017-04-11

USP22, a member of the deubiquitinases (DUBs) family, is known to be a key subunit of the human Spt-Ada-Gcn5 acetyltransferase (hSAGA) transcriptional cofactor complex. Within hSAGA, USP22 removes ubiquitin from histone proteins, thus regulating the transcription and expression of downstream genes. USP22 plays important roles in many cancers; however, its effect and the mechanism underlying HCC chemoresistance remain unclear. In the present study, we found that USP22 was highly expressed in chemoresistant HCC tissues and cells and was correlated with the prognosis of HCC patients who received chemotherapy. Silencing USP22 in chemoresistant HCC Bel/Fu cells dramatically inhibited proliferation, migration, invasion and epithelial-mesenchymal transition in vitro; suppressed tumorigenic and metastatic capacities in vivo; and inhibited drug resistance-related proteins (MDR1, LRP, MRP1). Mechanistically, we found that USP22 knockdown exerts its function through down-regulating PI3K and activating Smad4, which inhibited phosphorylation of Akt. Silencing Smad4 blocked USP22 knockdown-induced Akt inhibition in Bel/Fu cells. Our results, for the first time, provide evidence that USP22 plays a critical role in the development of chemoresistant HCC cells and that high USP22 expression serves as a molecular marker for the prognosis of HCC patients who undergo chemotherapy.

Identification of Small Molecule Inhibitors of microRNA Involved in Chemoresistance and Cancer Stem Cells for Ovarian Cancer Intervention

DTIC Science & Technology

2012-03-01

respectively, the com pounds that overcom e the effects of m iR-19a/b and m iR-221/222 on the luciferase activity will be considered as candida tes of...Chellappan SP , Haura EB, Cheng JQ. IKBKE is induced by S TAT3 and tobacco carcinogen and determ ines chemosensitivity in n on-small cell lung cancer

Early Diagnosis, Treatment and Care of Cancer Patients

DTIC Science & Technology

2012-09-01

penalty for failing to comply with a collection of information if it does not display a currently valid OMB control number. PLEASE DO NOT RETURN YOUR...project #1. This will be done by application of inhibitors of stem cells as a novel approach for eradication of leukemia tumor cells. Parthenolide (PTL...treated with these substances, and will assess whether parthenolide can function as a chemosensitizing agent for various conventional chemotherapy

Down-regulation of HECTD3 by HER2 inhibition makes serous ovarian cancer cells sensitive to platinum treatment.

PubMed

Shu, Tong; Li, Yi; Wu, Xiaowei; Li, Bin; Liu, Zhihua

2017-12-28

Resistance to platinum-based chemotherapy is a major cause of treatment failure in patients with epithelial ovarian cancer and predicts a poor prognosis. Previously, we found that HECTD3 confers cancer cell resistance to apoptosis. However, the significance of HECTD3 expression in ovarian cancer and its regulatory mechanisms were unknown. Here, we found that HECTD3 depletion promotes carboplatin-induced apoptosis in both an ovarian cancer cell model and a xenograft mouse model. Moreover, high HECTD3 expression is significantly associated with poor platinum response and prognosis in ovarian cancer patients. We further demonstrated that HER2 can up-regulate HECTD3 expression through activating STAT3. Furthermore, HER2 inhibitors, such as lapatinib, down-regulate HECTD3 expression and thus promote the chemosensitivity of ovarian cancer cells to carboplatin. Lapatinib combined with carboplatin also significantly inhibits serous ovarian carcinoma growth compared with each drug alone in a xenograft mouse model. HECTD3 may be considered a promising molecular predictor of platinum chemosensitivity and prognosis for serous ovarian cancer. Through decreasing HECTD3, lapatinib possesses significantly increased anti-tumor activity when combined with carboplatin compared with each agent alone, which provides an optional therapeutic regimen for serous ovarian cancer. Copyright © 2017 Elsevier B.V. All rights reserved.

Anti-protozoal and anti-bacterial antibiotics that inhibit protein synthesis kill cancer subtypes enriched for stem cell-like properties.

PubMed

Cuyàs, Elisabet; Martin-Castillo, Begoña; Corominas-Faja, Bruna; Massaguer, Anna; Bosch-Barrera, Joaquim; Menendez, Javier A

2015-01-01

Key players in translational regulation such as ribosomes might represent powerful, but hitherto largely unexplored, targets to eliminate drug-refractory cancer stem cells (CSCs). A recent study by the Lisanti group has documented how puromycin, an old antibiotic derived from Streptomyces alboniger that inhibits ribosomal protein translation, can efficiently suppress CSC states in tumorspheres and monolayer cultures. We have used a closely related approach based on Biolog Phenotype Microarrays (PM), which contain tens of lyophilized antimicrobial drugs, to assess the chemosensitivity profiles of breast cancer cell lines enriched for stem cell-like properties. Antibiotics directly targeting active sites of the ribosome including emetine, puromycin and cycloheximide, inhibitors of ribosome biogenesis such as dactinomycin, ribotoxic stress agents such as daunorubicin, and indirect inhibitors of protein synthesis such as acriflavine, had the largest cytotoxic impact against claudin-low and basal-like breast cancer cells. Thus, biologically aggressive, treatment-resistant breast cancer subtypes enriched for stem cell-like properties exhibit exacerbated chemosensitivities to anti-protozoal and anti-bacterial antibiotics targeting protein synthesis. These results suggest that old/existing microbicides might be repurposed not only as new cancer therapeutics, but also might provide the tools and molecular understanding needed to develop second-generation inhibitors of ribosomal translation to eradicate CSC traits in tumor tissues.

Anti-protozoal and anti-bacterial antibiotics that inhibit protein synthesis kill cancer subtypes enriched for stem cell-like properties

PubMed Central

Cuyàs, Elisabet; Martin-Castillo, Begoña; Corominas-Faja, Bruna; Massaguer, Anna; Bosch-Barrera, Joaquim; Menendez, Javier A

2015-01-01

Key players in translational regulation such as ribosomes might represent powerful, but hitherto largely unexplored, targets to eliminate drug-refractory cancer stem cells (CSCs). A recent study by the Lisanti group has documented how puromycin, an old antibiotic derived from Streptomyces alboniger that inhibits ribosomal protein translation, can efficiently suppress CSC states in tumorspheres and monolayer cultures. We have used a closely related approach based on Biolog Phenotype Microarrays (PM), which contain tens of lyophilized antimicrobial drugs, to assess the chemosensitivity profiles of breast cancer cell lines enriched for stem cell-like properties. Antibiotics directly targeting active sites of the ribosome including emetine, puromycin and cycloheximide, inhibitors of ribosome biogenesis such as dactinomycin, ribotoxic stress agents such as daunorubicin, and indirect inhibitors of protein synthesis such as acriflavine, had the largest cytotoxic impact against claudin-low and basal-like breast cancer cells. Thus, biologically aggressive, treatment-resistant breast cancer subtypes enriched for stem cell-like properties exhibit exacerbated chemosensitivities to anti-protozoal and anti-bacterial antibiotics targeting protein synthesis. These results suggest that old/existing microbicides might be repurposed not only as new cancer therapeutics, but also might provide the tools and molecular understanding needed to develop second-generation inhibitors of ribosomal translation to eradicate CSC traits in tumor tissues. PMID:25970790

Solanine induced apoptosis and increased chemosensitivity to Adriamycin in T-cell acute lymphoblastic leukemia cells.

PubMed

Yi, Ying-Jie; Jia, Xiu-Hong; Wang, Jian-Yong; Chen, Jie-Ru; Wang, Hong; Li, You-Jie

2018-05-01

Solanine is an alkaloid and is the main extract of the traditional Chinese herb, Solanum nigrum Linn . It has been reported that Solanine has anti-inflammatory and antitumor properties. The present study aimed to investigate the antitumor effect of Solanine in Jurkat cells and demonstrate the molecular mechanism of antitumor activity of Solanine. A Cell Counting Kit-8 assay demonstrated that Solanine inhibited the proliferation of Jurkat cells in a dose-and time-dependent manner. Cell apoptosis was measured by flow cytometry. Flow cytometry revealed that Solanine induced apoptosis in a dose-dependent manner in Jurkat cells. Reverse transcription-quantitative polymerase chain reaction demonstrated that Solanine modulated the mRNA levels of B-cell lymphoma-2 (Bcl-2) and Bcl-2-associated X protein (Bax). Additionally, Bcl-2 and Bax expression was measured using western blot analysis. Western blot analysis revealed a significant increase in the expression of Bax and decrease in the expression of Bcl-2. Solanine increased the chemosensitivity of Jurkat cells to Adriamycin. In summary, the present results indicated that the antitumor activity of Solanine was associated with inhibition of cell proliferation, induction of apoptosis and increasing cytotoxicity of Adriamycin. Therefore, Solanine may have potential as a novel agent for the treatment of acute lymphocytic leukemia.

Water extract from Pleurotus pulmonarius with antioxidant activity exerts in vivo chemoprophylaxis and chemosensitization for liver cancer.

PubMed

Xu, Wen Wen; Li, Bin; Lai, Emily Tsz Ching; Chen, Lei; Huang, Jim Jun Hui; Cheung, Annie Lai Man; Cheung, Peter Chi Keung

2014-01-01

Chemoprophylaxis and chemosensitization are promising strategies to combat human cancers. Natural antioxidant agents show great promise in cancer therapy, and the use of edible mushrooms against cancer is receiving more interest globally. In this study, the radical scavenging activities including diphenyl-1-picrylhydrazyl, superoxide anion radical, hydroxyl radical, and hydrogen peroxide were compared among hot water extracts from 3 edible mushrooms, among which Pleurotus pulmonarius (Pp) possessed the highest antioxidant potential. Oral administration of Pp 2 wk in advance could markedly inhibit the incidence and size of tumor (Huh7 liver cancer cells) with an inhibition rate of 93.1% in nude mice. No obvious side effect was observed in the Pp-treated mice as indicated by their body weight and histological analysis of major organs. The cancer prevention by Pp treatment might be explained by the inhibition of cancer cell proliferation indicated by reduction of ki-67 staining and the inactivation of phosphoinositide 3-kinase (PI3K)/AKT signaling pathway in the Pp-treated mice. Furthermore, a significant synergistic effect was observed when the mice were treated with a combination of low dose of cisplatin and Pp. Taken together, these results suggest the potential application of Pp as an adjuvant in the chemotherapy of liver cancer.

Genetic markers predictive of chemosensitivity and outcome in gliomatosis cerebri.

PubMed

Kaloshi, G; Everhard, S; Laigle-Donadey, F; Marie, Y; Navarro, S; Mokhtari, K; Idbaih, A; Ducray, F; Thillet, J; Hoang-Xuan, K; Delattre, J-Y; Sanson, M

2008-02-19

Up-front temozolomide (TMZ) has been recently proposed as a treatment for gliomatosis cerebri (GC), but no predictive or prognostic markers have been identified so far. Because 1p19q codeletion and methylguanine methyl transferase promoter (MGMTP) methylation have been correlated with chemosensitivity of gliomas, their value was investigated in a cohort of patients with GC treated with TMZ. A cohort of 25 GC patients who were treated with TMZ was investigated for 1p19q codeletion and O6-methylguanine DNA. Patients with a 1p/19q codeletion had a higher response rate (88% [8/9] vs 25% [4/16], p = 0.002), higher progression-free survival (24.5 vs 13.7 months, p = 0.017), and higher overall survival (66.8 vs 15.2 months, p = 0.011) than patients without 1p/19q codeletion. Fourteen of 19 evaluable tumors for MGMTP status were methylated. MGMTP methylation was associated with 1p/19q codeletion (p = 0.045). Patients with unmethylated MGMTP tended to have a shorter progression-free survival and a higher rate of progressive disease. Response rate to temozolomide and prognosis seem tightly correlated to 1p19q loss. The impact of methylguanine methyl transferase promoter methylation status on gliomatosis cerebri is still unsettled in this population.

Emodin enhances cisplatin-induced cytotoxicity in human bladder cancer cells through ROS elevation and MRP1 downregulation.

PubMed

Li, Xinxing; Wang, Haolu; Wang, Juan; Chen, Yuying; Yin, Xiaobin; Shi, Guiying; Li, Hui; Hu, Zhiqian; Liang, Xiaowen

2016-08-02

Chemoresistance is one of the most leading causes for tumor progression and recurrence of bladder cancer. Reactive oxygen species (ROS) plays a key role in the chemosensitivity of cancer cells. In the present study, emodin (1,3,8-trihydroxy-6-methylanthraquinone) was applied as a ROS generator in combination with cisplatin in T24 and J82 human bladder cancer cells. Cell viability and apoptosis rate of different treatment groups were detected by 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) and flow cytometry (FCM). The expression of transporters was measured at both the transcription and translation levels using PCR and western blotting. In vitro findings were confirmed by in vivo experiments using tumor-bearing mice. The expression of multidrug resistance-associated protein 1 (MRP1) in tumour tissue was measured using immunohistochemistry and side effects of the emodin/cisplatin co-treatment were investigated by histological examination. Emodin increased the cellular ROS level and effectively enhanced the cisplatin-induced cytotoxicity of T24 and J82 human bladder cancer cells through decreasing glutathione-cisplatin (GSH-cisplatin) conjugates. It blocked the chemoresistance of T24 and J82 cells to cisplatin through suppressing the expression of MRP1. This effect was specific in T24 and J82 cells but not in HCV-29 normal bladder epithelial cells. Consistent with in vitro experiments, emodin/cisplatin co-treatment increased the cell apoptosis and repressed the MRP1 expression in xenograft tumors, and without obvious systemic toxicity. This study revealed that emodin could increase the cisplatin-induced cytotoxicity against T24 and J82 cells via elevating the cellular ROS level and downregulating MRP1 expression. We suggest that emodin could serve as an effective adjuvant agent for the cisplatin-based chemotherapy of bladder cancer.

In Vitro and In Vivo Prostate Cancer Metastasis and Chemoresistance Can Be Modulated by Expression of either CD44 or CD147

PubMed Central

Hao, Jingli; Madigan, Michele C.; Khatri, Aparajita; Power, Carl A.; Hung, Tzong-Tyng; Beretov, Julia; Chang, Lei; Xiao, Weiwei; Cozzi, Paul J.; Graham, Peter H.; Kearsley, John H.; Li, Yong

2012-01-01

CD44 and CD147 are associated with cancer metastasis and progression. Our purpose in the study was to investigate the effects of down-regulation of CD44 or CD147 on the metastatic ability of prostate cancer (CaP) cells, their docetaxel (DTX) responsiveness and potential mechanisms involved in vitro and in vivo. CD44 and CD147 were knocked down (KD) in PC-3M-luc CaP cells using short hairpin RNA (shRNA). Expression of CD44, CD147, MRP2 (multi-drug resistance protein-2) and MCT4 (monocarboxylate tranporter-4) was evaluated using immunofluorescence and Western blotting. The DTX dose-response and proliferation was measured by MTT and colony assays, respectively. The invasive potential was assessed using a matrigel chamber assay. Signal transduction proteins in PI3K/Akt and MAPK/Erk pathways were assessed by Western blotting. An in vivo subcutaneous (s.c.) xenograft model was established to assess CaP tumorigenecity, lymph node metastases and DTX response. Our results indicated that KD of CD44 or CD147 decreased MCT4 and MRP2 expression, reduced CaP proliferation and invasive potential and enhanced DTX sensitivity; and KD of CD44 or CD147 down-regulated p-Akt and p-Erk, the main signal modulators associated with cell growth and survival. In vivo, CD44 or CD147-KD PC-3M-luc xenografts displayed suppressed tumor growth with increased DTX responsiveness compared to control xenografts. Both CD44 and CD147 enhance metastatic capacity and chemoresistance of CaP cells, potentially mediated by activation of the PI3K and MAPK pathways. Selective targeting of CD44/CD147 alone or combined with DTX may limit CaP metastasis and increase chemosensitivity, with promise for future CaP treatment. PMID:22870202

RWEN: Response-Weighted Elastic Net For Prediction of Chemosensitivity of Cancer Cell Lines. | Office of Cancer Genomics

Cancer.gov

Motivation: In recent years there have been several efforts to generate sensitivity profiles of collections of genomically characterized cell lines to panels of candidate therapeutic compounds. These data provide the basis for the development of in silico models of sensitivity based on cellular, genetic, or expression biomarkers of cancer cells. However, a remaining challenge is an efficient way to identify accurate sets of biomarkers to validate.

Chemosensitization of Breast Cancer Cells to Chemotherapeutic Agents by 3,3’-Diindolylmethane (DIM)

DTIC Science & Technology

2007-08-01

activity (Fig. 4A). More importantly, our animal studies showed that dietary B-DIM in combination with Taxotere also inhibited NF-κB DNA binding...κB DNA-binding activity (Fig. 4C). Importantly, our animal studies showed that dietary B-DIM in combination with Taxotere inhibited NF-κB DNA...Rahman et al 15 DISCUSSION Current reports have shown that plant-derived dietary compounds provide protection against the

Selective Chemosensitization of Rb Mutant Cells

DTIC Science & Technology

2000-07-01

Cambridge, MA). pLPC-12S coexpresses an E1A 12S cDNA with puromycin phosphotransferase (puro) and pWZL-12S coexpresses E1A with hygromycin phospho...retinoblastoma; CR1, -2, -3, conserved regions 1, 2, and 3; MEF, mouse embryonic fibroblast; puro, puromycin; hygro, hygromycin . To whom reprint requests...ml hygromycin B (Boehringer Mannheim) to elim- inate uninfected cells. When two separate E1A mutants were coexpressed, they were introduced

21 CFR 320.35 - Requirements for in vitro testing of each batch.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 5 2011-04-01 2011-04-01 false Requirements for in vitro testing of each batch... Determining the Bioavailability or Bioequivalence of Drug Products § 320.35 Requirements for in vitro testing of each batch. If a bioequivalence requirement specifies a currently available in vitro test or an in...

21 CFR 320.35 - Requirements for in vitro testing of each batch.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 5 2010-04-01 2010-04-01 false Requirements for in vitro testing of each batch... Determining the Bioavailability or Bioequivalence of Drug Products § 320.35 Requirements for in vitro testing of each batch. If a bioequivalence requirement specifies a currently available in vitro test or an in...

MSH3 Mismatch Repair Protein Regulates Sensitivity to Cytotoxic Drugs and a Histone Deacetylase Inhibitor in Human Colon Carcinoma Cells

PubMed Central

Park, Jae Myung; Huang, Shengbing; Tougeron, David; Sinicrope, Frank A.

2013-01-01

Background MSH3 is a DNA mismatch repair (MMR) gene that undergoes frequent somatic mutation in colorectal cancers (CRCs) with MMR deficiency. MSH3, together with MSH2, forms the MutSβ heteroduplex that interacts with interstrand cross-links induced by drugs such as cisplatin. To date, the impact of MSH3 on chemosensitivity is unknown. Methods We utilized isogenic HCT116 (MLH1−/MSH3−) cells where MLH1 is restored by transfer of chromosome 3 (HCT116+ch3) and also MSH3 by chromosome 5 (HCT116+3+5). We generated HCT116+3+5, SW480 (MLH1+/MSH3+) and SW48 (MLH1−/MSH3+) cells with shRNA knockdown of MSH3. Cells were treated with 5-fluorouracil (5-FU), SN-38, oxaliplatin, or the histone deacetylase (HDAC) inhibitor PCI-24781 and cell viability, clonogenic survival, DNA damage and apoptosis were analyzed. Results MSH3-deficient vs proficient CRC cells showed increased sensitivity to the irinotecan metabolite SN-38 and to oxaliplatin, but not 5-FU, as shown in assays for apoptosis and clonogenic survival. In contrast, suppression of MLH1 attenuated the cytotoxic effect of 5-FU, but did not alter sensitivity to SN-38 or oxaliplatin. The impact of MSH3 knockdown on chemosensitivity to SN-38 and oxaliplatin was maintained independent of MLH1 status. In MSH3-deficient vs proficient cells, SN-38 and oxaliplatin induced higher levels of phosphorylated histone H2AX and Chk2, and similar results were found in MLH1-proficient SW480 cells. MSH3-deficient vs proficient cells showed increased 53BP1 nuclear foci after irradiation, suggesting that MSH3 can regulate DNA double strand break (DSB) repair. We then utilized PCI-24781 that interferes with homologous recombination (HR) indicated by a reduction in Rad51 expression. The addition of PCI-24781 to oxaliplatin enhanced cytotoxicity to a greater extent compared to either drug alone. Conclusion MSH3 status can regulate the DNA damage response and extent of apoptosis induced by chemotherapy. The ability of MSH3 to regulate chemosensitivity was independent of MLH1 status. PCI-24781-mediated impairment of HR enhanced oxaliplatin sensitivity, suggesting that reduced DSB repair capacity may be contributory. PMID:23724141

MSH3 mismatch repair protein regulates sensitivity to cytotoxic drugs and a histone deacetylase inhibitor in human colon carcinoma cells.

PubMed

Park, Jae Myung; Huang, Shengbing; Tougeron, David; Sinicrope, Frank A

2013-01-01

MSH3 is a DNA mismatch repair (MMR) gene that undergoes frequent somatic mutation in colorectal cancers (CRCs) with MMR deficiency. MSH3, together with MSH2, forms the MutSβ heteroduplex that interacts with interstrand cross-links induced by drugs such as cisplatin. To date, the impact of MSH3 on chemosensitivity is unknown. We utilized isogenic HCT116 (MLH1-/MSH3-) cells where MLH1 is restored by transfer of chromosome 3 (HCT116+ch3) and also MSH3 by chromosome 5 (HCT116+3+5). We generated HCT116+3+5, SW480 (MLH1+/MSH3+) and SW48 (MLH1-/MSH3+) cells with shRNA knockdown of MSH3. Cells were treated with 5-fluorouracil (5-FU), SN-38, oxaliplatin, or the histone deacetylase (HDAC) inhibitor PCI-24781 and cell viability, clonogenic survival, DNA damage and apoptosis were analyzed. MSH3-deficient vs proficient CRC cells showed increased sensitivity to the irinotecan metabolite SN-38 and to oxaliplatin, but not 5-FU, as shown in assays for apoptosis and clonogenic survival. In contrast, suppression of MLH1 attenuated the cytotoxic effect of 5-FU, but did not alter sensitivity to SN-38 or oxaliplatin. The impact of MSH3 knockdown on chemosensitivity to SN-38 and oxaliplatin was maintained independent of MLH1 status. In MSH3-deficient vs proficient cells, SN-38 and oxaliplatin induced higher levels of phosphorylated histone H2AX and Chk2, and similar results were found in MLH1-proficient SW480 cells. MSH3-deficient vs proficient cells showed increased 53BP1 nuclear foci after irradiation, suggesting that MSH3 can regulate DNA double strand break (DSB) repair. We then utilized PCI-24781 that interferes with homologous recombination (HR) indicated by a reduction in Rad51 expression. The addition of PCI-24781 to oxaliplatin enhanced cytotoxicity to a greater extent compared to either drug alone. MSH3 status can regulate the DNA damage response and extent of apoptosis induced by chemotherapy. The ability of MSH3 to regulate chemosensitivity was independent of MLH1 status. PCI-24781-mediated impairment of HR enhanced oxaliplatin sensitivity, suggesting that reduced DSB repair capacity may be contributory.

Predictive value of CHFR and MLH1 methylation in human gastric cancer.

PubMed

Li, Yazhuo; Yang, Yunsheng; Lu, Youyong; Herman, James G; Brock, Malcolm V; Zhao, Po; Guo, Mingzhou

2015-04-01

Gastric carcinoma (GC) has one of the highest mortality rates of cancer diseases and has a high incidence rate in China. Palliative chemotherapy is the main treatment for advanced gastric cancer. It is necessary to compare the effectiveness and toxicities of different regimens. This study explores the possibility of methylation of DNA damage repair genes serving as a prognostic and chemo-sensitive marker in human gastric cancer. The methylation status of five DNA damage repair genes (CHFR, FANCF, MGMT, MLH1, and RASSF1A) was detected by nested methylation-specific PCR in 102 paraffin-embedded gastric cancer samples. Chi-square or Fisher's exact tests were used to evaluate the association of methylation status and clinic-pathological factors. The Kaplan-Meier method and Cox proportional hazards models were employed to analyze the association of methylation status and chemo-sensitivity. The results indicate that CHFR, MLH1, RASSF1A, MGMT, and FANCF were methylated in 34.3% (35/102), 21.6% (22/102), 12.7% (13/102), 9.8% (10/102), and 0% (0/102) of samples, respectively. No association was found between methylation of CHFR, MLH1, RASSF1A, MGMT, or FANCF with gender, age, tumor size, tumor differentiation, lymph node metastasis, and TNM stage. In docetaxel-treated gastric cancer patients, resistance to docetaxel was found in CHFR unmethylated patients by Cox proportional hazards model (HR 0.243, 95% CI, 0.069-0.859, p = 0.028), and overall survival is longer in the CHFR methylated group compared with the CHFR unmethylated group (log-rank, p = 0.036). In oxaliplatin-treated gastric cancer patients, resistance to oxaliplatin was found in MLH1 methylated patients (HR 2.988, 95% CI, 1.064-8.394, p = 0.038), and overall survival was longer in the MLH1 unmethylated group compared with the MLH1 methylated group (log-rank, p = 0.046). CHFR is frequently methylated in human gastric cancer, and CHFR methylation may serve as a docetaxel-sensitive marker. MLH1 methylation was related to oxaliplatin resistance in gastric cancer patients.

GENOMIC PREDICTOR OF RESPONSE AND SURVIVAL FOLLOWING TAXANE-ANTHRACYCLINE CHEMOTHERAPY FOR INVASIVE BREAST CANCER

PubMed Central

Hatzis, Christos; Pusztai, Lajos; Valero, Vicente; Booser, Daniel J.; Esserman, Laura; Lluch, Ana; Vidaurre, Tatiana; Holmes, Frankie; Souchon, Eduardo; Martin, Miguel; Cotrina, José; Gomez, Henry; Hubbard, Rebekah; Chacón, J. Ignacio; Ferrer-Lozano, Jaime; Dyer, Richard; Buxton, Meredith; Gong, Yun; Wu, Yun; Ibrahim, Nuhad; Andreopoulou, Eleni; Ueno, Naoto T.; Hunt, Kelly; Yang, Wei; Nazario, Arlene; DeMichele, Angela; O’Shaughnessy, Joyce; Hortobagyi, Gabriel N.; Symmans, W. Fraser

2017-01-01

CONTEXT Accurate prediction of who will (or won’t) have high probability of survival benefit from standard treatments is fundamental for individualized cancer treatment strategies. OBJECTIVE To develop a predictor of response and survival from chemotherapy for newly diagnosed invasive breast cancer. DESIGN Development of different predictive signatures for resistance and response to neoadjuvant chemotherapy (stratified according to estrogen receptor (ER) status) from gene expression microarrays of newly diagnosed breast cancer (310 patients). Then prediction of breast cancer treatment-sensitivity using the combination of signatures for: 1) sensitivity to endocrine therapy, 2) chemo-resistance, and 3) chemo-sensitivity. Independent validation (198 patients) and comparison with other reported genomic predictors of chemotherapy response. SETTING Prospective multicenter study to develop and test genomic predictors for neoadjuvant chemotherapy. PATIENTS Newly diagnosed HER2-negative breast cancer treated with chemotherapy containing sequential taxane and anthracycline-based regimens then endocrine therapy (if hormone receptor-positive). MAIN OUTCOME MEASURES Distant relapse-free survival (DRFS) if predicted treatment-sensitive and absolute risk reduction (ARR, difference in DRFS of the two predicted groups) at median follow-up (3 years), and their 95% confidence intervals (CI). RESULTS Patients in the independent validation cohort (99% clinical Stage II–III) who were predicted to be treatment-sensitive (28% of total) had DRFS of 92% (CI 85–100) and survival benefit compared to others (absolute risk reduction (ARR) 18%; CI 6–28). Predictions were accurate if breast cancer was ER-positive (30% predicted sensitive, DRFS 97%, CI 91–100; ARR 11%, CI 0.1–21) or ER-negative (26% predicted sensitive, DRFS 83%, CI 68–100; ARR 26%, CI 4–28), and were significant in multivariate analysis after adjusting for relevant clinical-pathologic characteristics. Other genomic predictors showed paradoxically worse survival if predicted to be responsive to chemotherapy. CONCLUSION A genomic predictor combining ER status, predicted chemo-resistance, predicted chemo-sensitivity, and predicted endocrine sensitivity accurately identified patients with survival benefit following taxane-anthracycline chemotherapy. PMID:21558518

[Biological behavior of hypopharyngeal carcinoma].

PubMed

Zhou, L X

1997-01-01

Hypopharyngeal squamous cell carcinomas (HPC) has an extremely poor prognosis. Characteristics of cell lines of head and neck squamous cell carcinomas including HPC were studied by various methods, e.g., chemosensitivity test and the immunohistochemistry staining method, to determine whether this poor prognosis is due to the biological behavior of this cancer. An HPC cell line was found to be resistant to anti tumor drugs, i.e., PEP, MTX and CPM and moderately sensitive to CDDP, 5-FU and ADM. Thermoresistance to hyperthermatic treatment and weak expression of ICAM-1 on the HPC cell line were observed. DNA synthesis by the HPC cell line was induced by stimulation with a low concentration of EGF and the amount of EGFR on these HPC cells was very high. In addition, cyclinD1 overexpression was found in the HPC cell line. Based on the above findings, further analysis of hypopharyngeal carcinoma cells and the development of a new treatment modality to control tumor growth and metastatic factors influencing the poor outcome are necessary to improve the prognosis of this cancer.

ABCC3 as a marker for multidrug resistance in non-small cell lung cancer

PubMed Central

Zhao, Yanbin; Lu, Hailing; Yan, An; Yang, Yanmei; Meng, Qingwei; Sun, Lichun; Pang, Hui; Li, Chunhong; Dong, Xiaoqun; Cai, Li

2013-01-01

Multidrug resistance (MDR) contributes to the failure of chemotherapy and high mortality in non-small cell lung cancer (NSCLC). We aim to identify MDR genes that predict tumor response to chemotherapy. 199 NSCLC fresh tissue samples were tested for chemosensitivity by MTT assay. cDNA microarray was done with 5 samples with highest resistance and 6 samples with highest sensitivity. Expression of ABCC3 mRNA and protein was detected by real-time PCR and immunohistochemisty, respectively. The association between gene expression and overall survival (OS) was examined using Cox proportional hazard regression. 44 genes were upregulated and 168 downregulated in the chemotherapy-resistant group. ABCC3 was one of the most up-regulated genes in the resistant group. ABCC3-positive expression correlated with lymph node involvement, advanced TNM stage, more malignant histological type, multiple-resistance to anti-cancer drugs, and reduced OS. ABCC3 expression may serve as a marker for MDR and predictor for poor clinical outcome of NSCLC. PMID:24176985

21 CFR 312.160 - Drugs for investigational use in laboratory research animals or in vitro tests.

Code of Federal Regulations, 2010 CFR

2010-04-01

... research animals or in vitro tests. 312.160 Section 312.160 Food and Drugs FOOD AND DRUG ADMINISTRATION... Drugs for Investigational Use in Laboratory Research Animals or In Vitro Tests § 312.160 Drugs for investigational use in laboratory research animals or in vitro tests. (a) Authorization to ship. (1)(i) A person...

21 CFR 312.160 - Drugs for investigational use in laboratory research animals or in vitro tests.

Code of Federal Regulations, 2013 CFR

2013-04-01

... research animals or in vitro tests. 312.160 Section 312.160 Food and Drugs FOOD AND DRUG ADMINISTRATION... Drugs for Investigational Use in Laboratory Research Animals or In Vitro Tests § 312.160 Drugs for investigational use in laboratory research animals or in vitro tests. (a) Authorization to ship. (1)(i) A person...

21 CFR 312.160 - Drugs for investigational use in laboratory research animals or in vitro tests.

Code of Federal Regulations, 2014 CFR

2014-04-01

... research animals or in vitro tests. 312.160 Section 312.160 Food and Drugs FOOD AND DRUG ADMINISTRATION... Drugs for Investigational Use in Laboratory Research Animals or In Vitro Tests § 312.160 Drugs for investigational use in laboratory research animals or in vitro tests. (a) Authorization to ship. (1)(i) A person...

21 CFR 312.160 - Drugs for investigational use in laboratory research animals or in vitro tests.

Code of Federal Regulations, 2012 CFR

2012-04-01

... research animals or in vitro tests. 312.160 Section 312.160 Food and Drugs FOOD AND DRUG ADMINISTRATION... Drugs for Investigational Use in Laboratory Research Animals or In Vitro Tests § 312.160 Drugs for investigational use in laboratory research animals or in vitro tests. (a) Authorization to ship. (1)(i) A person...

21 CFR 312.160 - Drugs for investigational use in laboratory research animals or in vitro tests.

Code of Federal Regulations, 2011 CFR

2011-04-01

... research animals or in vitro tests. 312.160 Section 312.160 Food and Drugs FOOD AND DRUG ADMINISTRATION... Drugs for Investigational Use in Laboratory Research Animals or In Vitro Tests § 312.160 Drugs for investigational use in laboratory research animals or in vitro tests. (a) Authorization to ship. (1)(i) A person...

Sirolimus induces apoptosis and reverses multidrug resistance in human osteosarcoma cells in vitro via increasing microRNA-34b expression.

PubMed

Zhou, Yan; Zhao, Rui-hua; Tseng, Kuo-fu; Li, Kun-peng; Lu, Zhi-gang; Liu, Yuan; Han, Kun; Gan, Zhi-hua; Lin, Shu-chen; Hu, Hai-yan; Min, Da-liu

2016-04-01

Multi-drug resistance poses a critical bottleneck in chemotherapy. Given the up-regulation of mTOR pathway in many chemoresistant cancers, we examined whether sirolimus (rapamycin), a first generation mTOR inhibitor, might induce human osteosarcoma (OS) cell apoptosis and increase the sensitivity of OS cells to anticancer drugs in vitro. Human OS cell line MG63/ADM was treated with sirolimus alone or in combination with doxorubicin (ADM), gemcitabine (GEM) or methotrexate (MTX). Cell proliferation and apoptosis were detected using CCK-8 assay and flow cytometry, respectively. MiRNAs in the cells were analyzed with miRNA microarray. The targets of miR-34b were determined based on TargetScan analysis and luciferase reporter assays. The expression of relevant mRNA and proteins was measured using qRT-PCR and Western blotting. MiR-34, PAK1 and ABCB1 levels in 40 tissue samples of OS patients were analyzed using qRT-PCR and in situ hybridization assays. Sirolimus (1-100 nmol/L) dose-dependently suppressed the cell proliferation (IC50=23.97 nmol/L) and induced apoptosis. Sirolimus (10 nmol/L) significantly sensitized the cells to anticancer drugs, leading to decreased IC50 values of ADM, GEM and MTX (from 25.48, 621.41 and 21.72 μmol/L to 4.93, 73.92 and 6.77 μmol/L, respectively). Treatment of with sirolimus increased miR-34b levels by a factor of 7.5 in the cells. Upregulation of miR-34b also induced apoptosis and increased the sensitivity of the cells to the anticancer drugs, whereas transfection with miR-34b-AMO, an inhibitor of miR-34b, reversed the anti-proliferation effect of sirolimus. Two key regulators of cell cycle, apoptosis and multiple drug resistance, PAK1 and ABCB1, were demonstrated to be the direct targets of miR-34b. In 40 tissue samples of OS patients, significantly higher miR-34 ISH score and lower PAK5 and ABCB1 scores were detected in the chemo-sensitive group. Sirolimus increases the sensitivity of human OS cells to anticancer drugs in vitro by up-regulating miR-34b interacting with PAK1 and ABCB1. A low miR-34 level is an indicator of poor prognosis in OS patients.

Identification of the Microtubule-Inhibitor Activated Bcl-xL Kinase: A Regulator of Breast Cancer Cell Chemosensitivity to Taxol

DTIC Science & Technology

2011-08-01

not shown). 1 5 Translational research study We continued the clinical protocol entitled “Alterations in the Bcl-2 Family Proteins...Bcl- 2 protein phosphorylation in hematopoietic cells may be more likely to have fever, neutropenia than others, for example. While effective...Alterations in the Bcl-2 Family Proteins in the Peripheral Blood Following Treatment with Taxanes in Patients with Breast Cancer.” Accepted by the UAMS

Minimal Residual Disease in Acute Myeloid Leukemia: Still a Work in Progress?

PubMed Central

Mosna, Federico; Capelli, Debora; Gottardi, Michele

2017-01-01

Minimal residual disease evaluation refers to a series of molecular and immunophenotypical techniques aimed at detecting submicroscopic disease after therapy. As such, its application in acute myeloid leukemia has greatly increased our ability to quantify treatment response, and to determine the chemosensitivity of the disease, as the final product of the drug schedule, dose intensity, biodistribution, and the pharmakogenetic profile of the patient. There is now consistent evidence for the prognostic power of minimal residual disease evaluation in acute myeloid leukemia, which is complementary to the baseline prognostic assessment of the disease. The focus for its use is therefore shifting to individualize treatment based on a deeper evaluation of chemosensitivity and residual tumor burden. In this review, we will summarize the results of the major clinical studies evaluating minimal residual disease in acute myeloid leukemia in adults in recent years and address the technical and practical issues still hampering the spread of these techniques outside controlled clinical trials. We will also briefly speculate on future developments and offer our point of view, and a word of caution, on the present use of minimal residual disease measurements in “real-life” practice. Still, as final standardization and diffusion of the methods are sorted out, we believe that minimal residual disease will soon become the new standard for evaluating response in the treatment of acute myeloid leukemia. PMID:28587190

Autologous stem cell transplantation for patients aged 60 years or older with refractory or relapsed classical Hodgkin's lymphoma: a retrospective analysis from the French Society of Bone Marrow Transplantation and Cell Therapies (SFGM-TC).

PubMed

Stamatoullas, A; Brice, P; Gueye, M S; Mareschal, S; Chevallier, P; Bouabdallah, R; Nguyenquoc, S; Francois, S; Turlure, P; Ceballos, P; Monjanel, H; Bourhis, J-H; Guillerm, G; Mohty, M; Biron, P; Cornillon, J; Belhadj, K; Bonmati, C; Dilhuydy, M-S; Huynh, A; Bernard, M; Chrétien, M-L; Peffault de Latour, R; Tilly, H

2016-07-01

This report retrospectively analyzed the outcome of 91 patients aged 60 years or older with refractory/relapsed (R/R) classical Hodgkin's lymphoma (cHL) who underwent autologous stem cell transplantation (ASCT) between 1992 and 2013 and were reported to the French Society of Bone Marrow Transplantation and Cell Therapies registry. The median age at transplant was 63 years. The majority of patients exhibited disease chemosensitivity to salvage treatment (57 complete responses, 30 partial responses, 1 progressive disease and 3 unknown). The most frequent conditioning regimen consisted of BCNU, cytarabine, etoposide, melphalan (BEAM) chemotherapy (93%). With a median follow-up of 54 months, 5-year estimates of overall survival (OS) and progression free survival (PFS) for the entire group were 67 and 54%, respectively. Despite the missing data, in univariate analysis, the number of salvage chemotherapy lines (1-2 versus ⩾3) significantly influenced the OS, unlike the other prognostic factors (stage III-IV at relapse, disease status before ASCT and negative positron emission tomography (PET) scan) encountered in younger patients. In spite of its limitations, this retrospective study with a long-term follow-up suggests that ASCT is a valid treatment option for chemosensitive R/R cHL in selected elderly patients, with an acceptable rate of toxicity.

Inhibition of CD147 expression by RNA interference reduces proliferation, invasion and increases chemosensitivity in cancer stem cell-like HT-29 cells.

PubMed

Chen, Jie; Pan, Yuqin; He, Bangshun; Ying, Houqun; Wang, Feng; Sun, Huiling; Deng, Qiwen; Liu, Xian; Lin, Kang; Peng, Hongxin; Cho, William C; Wang, Shukui

2015-10-01

The association between CD147 and cancer stem cells (CSCs) provides a new angle for cancer treatments. The aim of this study was to investigate the biological roles of CD147 in colorectal CSCs. The Oct4-green fluorescent protein (GFP) vector was used to isolate CSCs and pYr-mir30-shRNA was used to generate short hairpin RNA (shRNA) specifically for CD147. After RNA interference (RNAi), CD147 was evaluated by reverse transcription‑quantitative PCR and western blot analysis, and its biological functions were assessed by MTT and invasion assays. The results showed that the differentiation of isolated CSC-like HT-29 cells was blocked and these cells were highly positive for CD44 and CD147. RNAi-mediated CD147 silencing reduced the expression of CD147 at both mRNA and protein levels. Moreover, the activities of proliferation and invasion were decreased obviously in CSCs. Knockdown of CD147 increased the chemosensitivity of CSC-like cells to gemcitabine, cisplatin, docetaxel at 0.1, 1 and 10 µM respectively, however, there was no significant difference among the three groups to paclitaxel at 10 µM. In conclusion, these results suggest that CD147 plays an important role in colorectal CSCs and might be regarded as a novel CSC-specific targeted strategy against colorectal cancer.

Peripheral T-cell lymphoma: autologous hematopoietic cell transplantation as first-line therapy.

PubMed

Laport, Ginna G

2010-09-01

The peripheral T-cell lymphomas (PTCL) are a heterogeneous group of non-Hodgkin's lymphomas associated with an unfavorable prognosis compared with the B-cell non-Hodgkin's lymphomas. The PTCLs are characterized by high remission rates after frontline therapy, but relapse inevitably occurs. The impact of high-dose chemotherapy with autologous hematopoietic cell transplantation (AHCT) as early consolidation therapy will be the focus of this review. In several prospective trials, only PTCL patients with responsive disease after induction chemotherapy proceeded to AHCT. The progression-free survivals ranged from 30% to 40% with low toxicity. The outcomes in retrospective trials appear more favorable but such trials were affected by a selection bias because only chemosensitive patients actually proceeded to AHCT, whereas the prospective studies were intention-to-treat analyses. Most of the published trials demonstrated that prognostic models such as the International Prognostic Index and the Prognostic Index for T-cell lymphoma help predict outcome after AHCT. Current data support the use of AHCT as early consolidation therapy for PTCL patients who are chemosensitive after induction chemotherapy. However, approximately one-third of patients are early induction failures and thus are not able to proceed to AHCT. Additionally, disease relapse remains the leading cause of treatment failure after AHCT, and thus more intensive treatment strategies or better noncross-resistant therapies are greatly needed early in the course of the disease.

Ablation of MCL1 expression by virally induced microRNA-29 reverses chemoresistance in human osteosarcomas

PubMed Central

Osaki, Shuhei; Tazawa, Hiroshi; Hasei, Joe; Yamakawa, Yasuaki; Omori, Toshinori; Sugiu, Kazuhisa; Komatsubara, Tadashi; Fujiwara, Tomohiro; Sasaki, Tsuyoshi; Kunisada, Toshiyuki; Yoshida, Aki; Urata, Yasuo; Kagawa, Shunsuke; Ozaki, Toshifumi; Fujiwara, Toshiyoshi

2016-01-01

Osteosarcoma is a rare disease diagnosed as malignant bone tumor. It is generally refractory to chemotherapy, which contributes to its poor prognosis. The reversal of chemoresistance is a major clinical challenge to improve the prognostic outcome of osteosarcoma patients. We developed a tumor-specific replication-competent oncolytic adenovirus, OBP-301 (telomelysin) and assessed its synergistic effects with chemotherapeutic agents (cisplatin and doxorubicin) using human osteosarcoma cell lines and a xenograft tumor model. The molecular mechanism underlying the chemosensitizing effect of OBP-301 was evaluated in aspects of apoptosis induction. OBP-301 inhibits anti-apoptotic myeloid cell leukemia 1 (MCL1) expression, which in turn leads to chemosensitization in human osteosarcoma cells. The siRNA-mediated knockdown of MCL1 expression sensitized human osteosarcoma cells to common chemotherapeutic agents. We also found that upregulation of microRNA-29 targeting MCL1 via virally induced transcriptional factor E2F-1 activation was critical for the enhancement of chemotherapy-induced apoptosis in osteosarcoma cells. Telomerase-specific oncolytic adenovirus synergistically suppressed the viability of human osteosarcoma cells in combination with chemotherapeutic agents. The combination treatment also significantly inhibited tumor growth, as compared to monotherapy, in an osteosarcoma xenograft tumor model. Our data suggest that replicative virus-mediated tumor-specific MCL1 ablation may be a promising strategy to attenuate chemoresistance in osteosarcoma patients. PMID:27356624

Triggering of the TRPV2 channel by cannabidiol sensitizes glioblastoma cells to cytotoxic chemotherapeutic agents.

PubMed

Nabissi, Massimo; Morelli, Maria Beatrice; Santoni, Matteo; Santoni, Giorgio

2013-01-01

The aggressive behavior of Glioblastoma multiforme (GBM) is mainly due to high invasiveness and proliferation rate as well as to high resistance to standard chemotherapy. Several chemotherapeutic agents like temozolomide (TMZ), carmustine (BCNU) or doxorubicin (DOXO) have been employed for treatment of GBM, but they display limited efficacy. Therefore, it is important to identify new treatment modalities to improve therapeutic effects and enhance GBM chemosensitivity. Recently, activation of the transient receptor potential vanilloid type 2 (TRPV2) has been found to inhibit human GBM cell proliferation and overcome BCNU resistance of GBM cells. Herein, we evaluated the involvement of cannabidiol (CBD)-induced TRPV2 activation, in the modulation of glioma cell chemosensitivity to TMZ, BCNU and DOXO. We found that CBD increases TRPV2 expression and activity. CBD by triggering TRPV2-dependent Ca(2+) influx increases drug uptake and synergizes with cytotoxic agents to induce apoptosis of glioma cells, whereas no effects were observed in normal human astrocytes. Moreover, as the pore region of transient receptor potential (TRP) channels is critical for ion channel permeation, we demonstrated that deletion of TRPV2 poredomain inhibits CBD-induced Ca(2+) influx, drug uptake and cytotoxic effects. Overall, we demonstrated that co-administration of cytotoxic agents together with the TRPV2 agonist CBD increases drug uptake and parallelly potentiates cytotoxic activity in human glioma cells.

MicroRNA-224 is associated with colorectal cancer progression and response to 5-fluorouracil-based chemotherapy by KRAS-dependent and -independent mechanisms

PubMed Central

Amankwatia, E B; Chakravarty, P; Carey, F A; Weidlich, S; Steele, R J C; Munro, A J; Wolf, C R; Smith, G

2015-01-01

Background: Colorectal cancers arise from benign adenomas, although not all adenomas progress to cancer and there are marked interpatient differences in disease progression. We have previously associated KRAS mutations with disease progression and reduced survival in colorectal cancer patients. Methods: We used TaqMan low-density array (TLDA) qRT–PCR analysis to identify miRNAs differentially expressed in normal colorectal mucosa, adenomas and cancers and in isogeneic KRAS WT and mutant HCT116 cells, and used a variety of phenotypic assays to assess the influence of miRNA expression on KRAS activity, chemosensitivity, proliferation and invasion. Results: MicroRNA-224 was differentially expressed in dysplastic colorectal disease and in isogeneic KRAS WT and mutant HCT116 cells. Antagomir-mediated miR-224 silencing in HCT116 KRAS WT cells phenocopied KRAS mutation, increased KRAS activity and ERK and AKT phosphorylation. 5-FU chemosensitivity was significantly increased in miR-224 knockdown cells, and in NIH3T3 cells expressing KRAS and BRAF mutant proteins. Bioinformatics analysis of predicted miR-224 target genes predicted altered cell proliferation, invasion and epithelial–mesenchymal transition (EMT) phenotypes that were experimentally confirmed in miR-224 knockdown cells. Conclusions: We describe a novel mechanism of KRAS regulation, and highlight the clinical utility of colorectal cancer-specific miRNAs as disease progression or clinical response biomarkers. PMID:25919696

Good cell culture practices &in vitro toxicology.

PubMed

Eskes, Chantra; Boström, Ann-Charlotte; Bowe, Gerhard; Coecke, Sandra; Hartung, Thomas; Hendriks, Giel; Pamies, David; Piton, Alain; Rovida, Costanza

2017-12-01

Good Cell Culture Practices (GCCP) is of high relevance to in vitro toxicology. The European Society of Toxicology In Vitro (ESTIV), the Center for Alternatives for Animal Testing (CAAT) and the In Vitro Toxicology Industrial Platform (IVTIP) joined forces to address by means of an ESTIV 2016 pre-congress session the different aspects and applications of GCCP. The covered aspects comprised the current status of the OECD guidance document on Good In Vitro Method Practices, the importance of quality assurance for new technological advances in in vitro toxicology including stem cells, and the optimized implementation of Good Manufacturing Practices and Good Laboratory Practices for regulatory testing purposes. General discussions raised the duality related to the difficulties in implementing GCCP in an academic innovative research framework on one hand, and on the other hand, the need for such GCCP principles in order to ensure reproducibility and robustness of in vitro test methods for toxicity testing. Indeed, if good cell culture principles are critical to take into consideration for all uses of in vitro test methods for toxicity testing, the level of application of such principles may depend on the stage of development of the test method as well as on the applications of the test methods, i.e., academic innovative research vs. regulatory standardized test method. Copyright © 2017 Elsevier Ltd. All rights reserved.

Evaluation of the cytotoxicity of the Bithionol - cisplatin combination in a panel of human ovarian cancer cell lines.

PubMed

Ayyagari, Vijayalakshmi N; Hsieh, Tsung-Han Jeff; Diaz-Sylvester, Paula L; Brard, Laurent

2017-01-13

Combination drug therapy appears a promising approach to overcome drug resistance and reduce drug-related toxicities in ovarian cancer treatments. In this in vitro study, we evaluated the antitumor efficacy of cisplatin in combination with Bithionol (BT) against a panel of ovarian cancer cell lines with special focus on cisplatin-sensitive and cisplatin-resistant cell lines. The primary objectives of this study are to determine the nature of the interactions between BT and cisplatin and to understand the mechanism(s) of action of BT-cisplatin combination. The cytotoxic effects of drugs either alone or in combination were evaluated using presto-blue assay. Cellular reactive oxygen species were measured by flow cytometry. Immunoblot analysis was carried out to investigate changes in levels of cleaved PARP, XIAP, bcl-2, bcl-xL, p21 and p27. Luminescent and colorimetric assays were used to test caspases 3/7 and ATX activity. The efficacy of the BT-cisplatin combination depends upon the cell type and concentrations of cisplatin and BT. In cisplatin-sensitive cell lines, BT and cisplatin were mostly antagonistic except when used at low concentrations, where synergy was observed. In contrast, in cisplatin-resistant cells, BT-cisplatin combination treatment displayed synergistic effects at most of the drug ratios/concentrations. Our results further revealed that the synergistic interaction was linked to increased reactive oxygen species generation and apoptosis. Enhanced apoptosis was correlated with loss of pro-survival factors (XIAP, bcl-2, bcl-xL), expression of pro-apoptotic markers (caspases 3/7, PARP cleavage) and enhanced cell cycle regulators p21 and p27. In cisplatin-resistant cell lines, BT potentiated cisplatin-induced cytotoxicity at most drug ratios via enhanced ROS generation and modulation of key regulators of apoptosis. Low doses of BT and cisplatin enhanced efficiency of cisplatin treatment in all the ovarian cancer cell lines tested. Our results suggest that novel combinations such as BT and cisplatin might be an attractive therapeutic approach to enhance ovarian cancer chemosensitivity. Combining low doses of cisplatin with subtherapeutic doses of BT can ultimately lead to the development of an innovative combination therapy to reduce/prevent the side effects normally occurring when high doses of cisplatin are administered.

Curcumin loaded pH-sensitive hybrid lipid/block copolymer nanosized drug delivery systems.

PubMed

Jelezova, Ivelina; Drakalska, Elena; Momekova, Denitsa; Shalimova, Natalia; Momekov, Georgi; Konstantinov, Spiro; Rangelov, Stanislav; Pispas, Stergios

2015-10-12

Curcumin is a perspective drug candidate with pleiotropic antineoplastic activity, whose exceptionally low aqueous solubility and poor pharmacokinetic properties have hampered its development beyond the preclinical level. A possible approach to overcome these limitations is the encapsulation of curcumin into nano-carriers, incl. liposomes. The present contribution is focused on feasibility of using hybrid pH-sensitive liposomes, whereby curcumin is entrapped as a free drug and as a water soluble inclusion complex with PEGylated tert-butylcalix[4]arene, which allows the drug to occupy both the phospholipid membranes and the aqueous core of liposomes. The inclusion complexes were encapsulated in dipalmithoylphosphathydilcholine:cholesterol liposomes, whose membranes were grafted with a poly(isoprene-b-acrylic acid) diblock copolymer to confer pH-sensitivity. The liposomes were characterized by DLS, ζ-potential measurements, cryo-TEM, curcumin encapsulation efficacy, loading capacity, and in vitro release as a function of pH. Free and formulated curcumin were further investigated for cytotoxicity, apoptosis-induction and caspase-8, and 9 activation in chemosensitive HL-60 and its resistant sublines HL-60/Dox and HL-60/CDDP. Formulated curcumin was superior cytotoxic and apoptogenic agent vs. the free drug. The mechanistic assay demonstrated that the potent proapoptotic effects of pH-sensitive liposomal curcumin presumably mediated via recruitment of both extrinsic and intrinsic apoptotic pathways in both HL-60 and HL-60/CDDP cells. Copyright © 2015 Elsevier B.V. All rights reserved.

Potential risks associated with traditional herbal medicine use in cancer care: A study of Middle Eastern oncology health care professionals.

PubMed

Ben-Arye, Eran; Samuels, Noah; Goldstein, Lee Hilary; Mutafoglu, Kamer; Omran, Suha; Schiff, Elad; Charalambous, Haris; Dweikat, Tahani; Ghrayeb, Ibtisam; Bar-Sela, Gil; Turker, Ibrahim; Hassan, Azza; Hassan, Esmat; Saad, Bashar; Nimri, Omar; Kebudi, Rejin; Silbermann, Michael

2016-02-15

The authors assessed the use of herbal medicine by Middle Eastern patients with cancer, as reported by their oncology health care professionals (HCPs). Herbal products identified by the study HCPs were evaluated for potential negative effects. Oncology HCPs from 16 Middle Eastern countries received a 17-item questionnaire asking them to list 5 herbal products in use by their patients with cancer. A literature search (PubMed, Micromedex, AltMedDex, and the Natural Medicine Comprehensive Database) was conducted to identify safety-related concerns associated with the products listed. A total of 339 HCPs completed the study questionnaire (response rate of 80.3%), identifying 44 herbal and 3 nonherbal nutritional supplements. Safety-related concerns were associated with 29 products, including herb-drug interactions with altered pharmacodynamics (15 herbs), direct toxic effects (18 herbs), and increased in vitro response of cancer cells to chemotherapy (7 herbs). Herbal medicine use, which is prevalent in Middle Eastern countries, has several potentially negative effects that include direct toxic effects, negative interactions with anticancer drugs, and increased chemosensitivity of cancer cells, requiring a reduction in dose-density. Oncology HCPs working in countries in which herbal medicine use is prevalent need to better understand the implications of this practice. The presence of integrative physicians with training in complementary and traditional medicine can help patients and their HCPs reach an informed decision regarding the safety and effective use of these products. © 2015 American Cancer Society.

Ubiquitous Release Of Exosomal Tumor Suppressor miR-6126 from Ovarian Cancer Cells

PubMed Central

Kanlikilicer, Pinar; Rashed, Mohammed H.; Bayraktar, Recep; Mitra, Rahul; Ivan, Cristina; Aslan, Burcu; Zhang, Xinna; Filant, Justyna; Silva, Andreia M.; Rodriguez-Aguayo, Cristian; Bayraktar, Emine; Pichler, Martin; Ozpolat, Bulent; Calin, George A.; Sood, Anil K.; Lopez-Berestein, Gabriel

2017-01-01

Cancer cells actively promote their tumorigenic behavior by reprogramming gene expression. Loading intraluminal vesicles with specific miRNAs and releasing them into the tumor microenvironment as exosomes is one mechanism of reprogramming whose regulation remains to be elucidated. Here, we report that miR-6126 is ubiquitously released in high abundance from both chemosensitive and chemoresistant ovarian cancer cells via exosomes. Overexpression of miR-6126 was confirmed in healthy ovarian tissue compared to ovarian cancer patient samples and correlated with better overall survival in high-grade serous ovarian cancer patients. miR-6126 acted as a tumor suppressor by directly targeting integrin β1, a key regulator of cancer cell metastasis. miR-6126 mimic treatment of cancer cells resulted in increased miR-6126 and decreased integrin β1 mRNA levels in the exosome. Functional analysis showed that treatment of endothelial cells with miR-6126 mimic significantly reduced tube formation as well as invasion and migration capacities of ovarian cancer cells in vitro. Administration of miR-6126 mimic in an orthotopic mouse model of ovarian cancer elicited a relative reduction in tumor growth, proliferating cells and microvessel density. miR-6126 inhibition promoted oncogenic behavior by leading ovarian cancer cells to release more exosomes. Our findings provide new insights into the role of exosomal miRNA-mediated tumor progression and suggest a new therapeutic approach to disrupt oncogenic phenotypes in tumors. PMID:27742688

Proteasome inhibition mediates p53 reactivation and anti-cancer activity of 6-gingerol in cervical cancer cells.

PubMed

Rastogi, Namrata; Duggal, Shivali; Singh, Shailendra Kumar; Porwal, Konica; Srivastava, Vikas Kumar; Maurya, Rakesh; Bhatt, M L B; Mishra, Durga Prasad

2015-12-22

Human papilloma virus (HPV) expressing E6 and E7 oncoproteins, is known to inactivate the tumor suppressor p53 through proteasomal degradation in cervical cancers. Therefore, use of small molecules for inhibition of proteasome function and induction of p53 reactivation is a promising strategy for induction of apoptosis in cervical cancer cells. The polyphenolic alkanone, 6-Gingerol (6G), present in the pungent extracts of ginger (Zingiber officinale Roscoe) has shown potent anti-tumorigenic and pro-apoptotic activities against a variety of cancers. In this study we explored the molecular mechanism of action of 6G in human cervical cancer cells in vitro and in vivo. 6G potently inhibited proliferation of the HPV positive cervical cancer cells. 6G was found to: (i) inhibit the chymotrypsin activity of proteasomes, (ii) induce reactivation of p53, (iii) increase levels of p21, (iv) induce DNA damage and G2/M cell cycle arrest, (v) alter expression levels of p53-associated apoptotic markers like, cleaved caspase-3 and PARP, and (vi) potentiate the cytotoxicity of cisplatin. 6G treatment induced significant reduction of tumor volume, tumor weight, proteasome inhibition and p53 accumulation in HeLa xenograft tumor cells in vivo. The 6G treatment was devoid of toxic effects as it did not affect body weights, hematological and osteogenic parameters. Taken together, our data underscores the therapeutic and chemosensitizing effects of 6G in the management and treatment of cervical cancer.

SiRNA knockdown of the DEK nuclear protein mRNA enhances apoptosis and chemosensitivity of canine transitional cell carcinoma cells.

PubMed

Yamazaki, Hiroki; Iwano, Tomomi; Otsuka, Saori; Kagawa, Yumiko; Hoshino, Yuki; Hosoya, Kenji; Okumura, Masahiro; Takagi, Satoshi

2015-04-01

Transitional cell carcinoma (TCC) in dogs is an aggressive malignant neoplasm, originating in the epithelium of the urinary bladder. The DEK nuclear protein is overexpressed in several types of human bladder cancer, where it is involved in chromatin reconstruction, gene transcription and apoptosis. Since DEK represents a potential therapeutic target for canine TCC, this study was designed to investigate DEK expression in canine TCC and to determine the effects of DEK mRNA silencing on TCC cells in vitro. The gene expression profiles of seven selected cancer-associated genes was assessed in four canine TCC cell lines and expression of DEK protein was evaluated in bladder tissue biopsies from healthy dogs and those affected with cystitis or TCC. After transfection of four canine TCC cell lines with DEK-specific or scrambled siRNA, annexin V staining was performed to evaluate apoptosis, and methylthiazole tetrazolium assays were performed to assess both cell viability and sensitivity to carboplatin. DEK mRNA expression was relatively high in canine TCC cells and expression of the DEK protein was significantly greater in TCC tumours compared with the other tissue samples. After transfection with DEK-specific siRNA, apoptosis, cell growth inhibition, and enhanced sensitivity to carboplatin were observed in all TCC cells assessed. These research findings suggest that DEK could be a potential therapeutic target for canine TCC. Copyright © 2015 Elsevier Ltd. All rights reserved.

miR-188-5p inhibits tumour growth and metastasis in prostate cancer by repressing LAPTM4B expression.

PubMed

Zhang, Hongtuan; Qi, Shiyong; Zhang, Tao; Wang, Andi; Liu, Ranlu; Guo, Jia; Wang, Yuzhuo; Xu, Yong

2015-03-20

Elucidation of the molecular targets and pathways regulated by the tumour-suppressive miRNAs can shed light on the oncogenic and metastatic processes in prostate cancer (PCa). Using miRNA profiling analysis, we find that miR-188-5p was significantly down-regulated in metastatic PCa. Down-regulation of miR-188-5p is an independent prognostic factor for poor overall and biochemical recurrence-free survival. Restoration of miR-188-5p in PCa cells (PC-3 and LNCaP) significantly suppresses proliferation, migration and invasion in vitro and inhibits tumour growth and metastasis in vivo. We also find overexpression of miR-188-5p in PC-3 cells can significantly enhance the cells' chemosensitivity to adriamycin. LAPTM4B is subsequently identified as a direct target of miR-188-5p in PCa, and is found to be significantly over-expressed in PCa. Knockdown of LAPTM4B phenotypically copies miR-188-5p-induced phenotypes, whereas ectopic expression of LAPTM4B reverses the effects of miR-188-5p. We also find that restoration of miR-188-5p can inhibit the PI3K/AKT signaling pathway via the suppression of LAPTM4B. Taken together, this is the first report unveils that miR-188-5p acts as a tumour suppressor in PCa and may therefore serve as a useful therapeutic target for the development of new anticancer therapy.

IGFBP2 modulates the chemoresistant phenotype in esophageal adenocarcinoma

PubMed Central

Myers, Amy L.; Lin, Lin; Nancarrow, Derek J.; Wang, Zhuwen; Ferrer-Torres, Daysha; Thomas, Dafydd G.; Orringer, Mark B.; Lin, Jules; Reddy, Rishindra M.; Beer, David G.; Chang, Andrew C.

2015-01-01

Esophageal adenocarcinoma (EAC) patients commonly present with advanced stage disease and demonstrate resistance to therapy, with response rates below 40%. Understanding the molecular mechanisms of resistance is crucial for improvement of clinical outcomes. IGFBP2 is a member of the IGFBP family of proteins that has been reported to modulate both IGF and integrin signaling and is a mediator of cell growth, invasion and resistance in other tumor types. In this study, high IGFBP2 expression was observed in a subset of primary EACs and was found to be significantly higher in patients with shorter disease-free intervals as well as in treatment-resistant EACs as compared to chemonaive EACs. Modulation of IGFBP2 expression in EAC cell lines promoted cell proliferation, migration and invasion, implicating a role in the metastatic potential of these cells. Additionally, knockdown of IGFBP2 sensitized EAC cells to cisplatin in a serum-dependent manner. Further in vitro exploration into this chemosensitization implicated both the AKT and ERK pathways. Silencing of IGFBP2 enhanced IGF1-induced immediate activation of AKT and reduced cisplatin-induced ERK activation. Addition of MEK1/2 (selumetinib or trametinib) or AKT (AKT Inhibitor VIII) inhibitors enhanced siIGFBP2-induced sensitization of EAC cells to cisplatin. These results suggest that targeted inhibition of IGFBP2 alone or together with either the MAPK or PI3K/AKT signaling pathway in IGFBP2-overexpressing EAC tumors may be an effective approach for sensitizing resistant EACs to standard neoadjuvant chemotherapy. PMID:26317790

Inhibition of c-Myc by 10058-F4 induces growth arrest and chemosensitivity in pancreatic ductal adenocarcinoma.

PubMed

Zhang, Meng; Fan, Hai-Yan; Li, Sheng-Chao

2015-07-01

Pancreatic ductal adenocarcinoma (PDAC) is a formidable medical challenge due to its malignancies and the absence of effective treatment. c-Myc, as an important transcription factor, plays crucial roles in cell cycle progression, apoptosis and cellular transformation. The c-Myc inhibitor, 10058-F4, has been reported act as a tumor suppressor in several different tumors. In current study, the tumor-suppressive roles of 10058-F4 was observed in human pancreatic cancer cells in vitro as demonstrated by decreased cell viability, cell cycle arrest at the G1/S transition and increased caspase3/7 activity. And tumor responses to gemcitabine were also significantly enhanced by 10058-F4 in PANC-1 and SW1990 cells. In a subcutaneous xenograft model, however, 10058-F4 showed no significant influence on pancreatic tumorigenesis. When combined with gemcitabine, tumorigenesis was drastically attenuated compared with gemcitabine group or 10058-F4 group; this synergistic effect was accompanied with decreased PCNA-positive cells and reduced TUNEL-positive cells in the combined treated group. Subsequent studies revealed that decreased glycolysis may be involved in the inhibitory effect of 10058-F4 on PDAC. Taken together, this study demonstrates the roles of 10058-F4 in PDAC and provides evidence that 10058-F4 in combination with gemcitabine showed significant clinical benefit over the usage of gemcitabine alone. Copyright © 2015. Published by Elsevier Masson SAS.

The upper respiratory tract: mucous membrane irritation.

PubMed Central

Bascom, R

1991-01-01

Despite the widespread recognition that mucosal irritation is a cardinal feature of "sick-building syndrome," few data exist on the cause, natural history, or pathophysiology of upper respiratory mucous membrane irritation. The baseline prevalence of nasal symptoms among building occupants is often 20%, but in some studies it is as high as 50 to 60%. New techniques of nasal challenge and analysis of cells and mediators in nasal lavage fluid have proved useful in the assessment of rhinitis caused by antigens, cold air, and viruses, and these techniques are now being applied to the study the response to irritants. Human inhalation challenge studies have recently demonstrated a spectrum of sensitivity to environmental tobacco smoke, but the basis for this difference requires additional investigation. Animal and in vitro studies indicate that the chemosensitive neurons and airway epithelium may be critical targets for irritants that participate in the induction of inflammation. New research methods are needed, particularly to evaluate complaints of nasal congestion, drying, and irritation. Techniques should be developed that may be useful for field studies, where the health effects of a complex mixture are being assessed in a specific indoor environment. There exists a group of individuals who report a variety of symptoms on exposure to low levels of common volatile organic mixtures such as perfume, cigarette smoke, and cleaning agents. Some of these individuals report having occupied "sick buildings" during the time their symptoms began. Research is needed to understand the basis of their complaints, their etiology, and treatment. PMID:1821376

Proteasome inhibition mediates p53 reactivation and anti-cancer activity of 6-Gingerol in cervical cancer cells

PubMed Central

Rastogi, Namrata; Duggal, Shivali; Singh, Shailendra Kumar; Porwal, Konica; Srivastava, Vikas Kumar; Maurya, Rakesh; Bhatt, Madan L.B.; Mishra, Durga Prasad

2015-01-01

Human papilloma virus (HPV) expressing E6 and E7 oncoproteins, is known to inactivate the tumor suppressor p53 through proteasomal degradation in cervical cancers. Therefore, use of small molecules for inhibition of proteasome function and induction of p53 reactivation is a promising strategy for induction of apoptosis in cervical cancer cells. The polyphenolic alkanone, 6-Gingerol (6G), present in the pungent extracts of ginger (Zingiber officinale Roscoe) has shown potent anti-tumorigenic and pro-apoptotic activities against a variety of cancers. In this study we explored the molecular mechanism of action of 6G in human cervical cancer cells in vitro and in vivo. 6G potently inhibited proliferation of the HPV positive cervical cancer cells. 6G was found to: (i) inhibit the chymotrypsin activity of proteasomes, (ii) induce reactivation of p53, (iii) increase levels of p21, (iv) induce DNA damage and G2/M cell cycle arrest, (v) alter expression levels of p53-associated apoptotic markers like, cleaved caspase-3 and PARP, and (vi) potentiate the cytotoxicity of cisplatin. 6G treatment induced significant reduction of tumor volume, tumor weight, proteasome inhibition and p53 accumulation in HeLa xenograft tumor cells in vivo. The 6G treatment was devoid of toxic effects as it did not affect body weights, hematological and osteogenic parameters. Taken together, our data underscores the therapeutic and chemosensitizing effects of 6G in the management and treatment of cervical cancer. PMID:26621832

PARP1 impact on DNA repair of platinum adducts: preclinical and clinical read-outs.

PubMed

Olaussen, Ken A; Adam, Julien; Vanhecke, Elsa; Vielh, Philippe; Pirker, Robert; Friboulet, Luc; Popper, Helmut; Robin, Angélique; Commo, Fréderic; Thomale, Jürgen; Kayitalire, Louis; Filipits, Martin; Le Chevalier, Thierry; André, Fabrice; Brambilla, Elisabeth; Soria, Jean-Charles

2013-05-01

Evaluation of DNA repair proteins might provide meaningful information in relation to prognosis and chemotherapy efficacy in Non-Small Cell Lung Cancer (NSCLC) patients. The role of Poly(ADP-Ribose) Polymerase (PARP) in DNA repair of platinum adducts has not been firmly established. We used a DNA repair functional test based on antibody recognition of cisplatin intrastrand platinum adducts on DNA. We evaluated the effect of PARP inhibition on DNA repair functionality in a panel of cisplatin cell lines treated by the clinical-grade pharmacological inhibitor CEP8983 (a 4-methoxy-carbazole derivate) and the commercially available inhibitor PJ34 (phenanthridinone). We determined PARP1 protein expression in whole tumor sections from the International Adjuvant Lung cancer Trial (IALT)-bio study and tested a 3-marker PARP1/MSH2/ERCC1 algorithm combining PARP1 tumor status with previously published data. Chemosensitivity of cisplatin in NSCLC cell lines was correlated with the accumulation of cisplatin DNA adducts (P=0.0004). Further, the pharmacological inhibition of PARP induced a 1.7 to 2.3-fold increase in platinum adduct accumulation (24h) in A549 cell line suggesting a slow-down of platinum DNA-adduct repair capacity. In parallel, PARP1 inhibition increased the sensitivity to cisplatin treatment. In patient samples, PARP1 expression levels did not influence patient survival or the effect of platinum-based post-operative chemotherapy in the global IALT-bio population (interaction P=0.79). Among cases with high expression of all three markers (triple positive), untreated patients had prolonged survival with a median DFS of 7.8 years, (HR=0.34, 95%CI [0.19-0.61], adjusted P=0.0003) compared to triple negative patients (1.4 years). Remarkably, triple positive patients suffered from a detrimental effect (4.9-year reduction of median DFS) by post-operative cisplatin-based chemotherapy (HR=1.79, 95%CI [1.01-3.17], adjusted P=0.04, chemotherapy vs. control). Combinatorial sub-group analysis of the 3 markers further suggested that PARP1 tumor positivity might constitute a molecular context with high theranostic interest of ERCC1 and MSH2 in NSCLC. In conclusion, our data confirm that platinum DNA adduct accumulation is linked to chemosensitivity, which increase by pharmacological PARP inhibitors points to a role of PARP-dependent DNA repair in the process. We further suggest DNA repair biomarkers should be analyzed in a larger context of multiple DNA repair pathway regulation. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

77 FR 41406 - Evaluation of In Vitro Tests for Identifying Eye Injury Hazard Potential of Chemicals and...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-07-13

... DEPARTMENT OF HEALTH AND HUMAN SERVICES Evaluation of In Vitro Tests for Identifying Eye Injury...-animal testing strategies proposed for identifying eye injury hazard potential of chemicals and products... Panel and submission of data from substances tested in in vitro tests for identifying eye injury hazard...

Mechanisms of Resistance to Chemotherapies Targeting BRCA-Mutant Breast Cancer

DTIC Science & Technology

2015-12-01

limiting for mutagenic NHEJ but not for physiological CSR. An implication of our results is that deregulation of the RNF168/53BP1 pathway could alter the...resistance in BRCA-deficient tumors. We have also observed that deregulation of the RNF168/53BP1 pathway can alter the chemosensitivity of BRCA1 deficient...FASEB Summer Research Conference. Big Sky, Montana, 2015 g. Invited Speaker, Conference "Chromatin and Cell Fate", Essen, Germany , 2015 h. Invited

[Possible role of autotransplantation in small cel bronchial carcinoma].

PubMed

Tiefengraber, E; Sebesta, C; Kier, P; Ruckser, R; Habertheuer, K H; Hinterberger, W

1995-01-01

Autologous bone marrow transplantation (ABMT) performed with recent achievements plays yet no established role in the treatment of small cell lung cancer (SCLC). The majority of treatment results obtained so far do not clearly suggest a superiority of high-dose therapy with autologous transplantation over conventional polychemo/radiotherapy. It is unknown, whether or not a subgroup of patients with, e.g., "limited disease" and chemosensitive tumor may benefit from ABMT. Randomized trials will be necessary to clarify this question.

Metal Occupancy of Zinc Finger Motifs as Determinants for Zn2+-Mediated Chemosensitization of Prostate Cancer Cells

DTIC Science & Technology

2013-12-01

leukemia (AML) and glioblastoma ( GBM ). Our laboratory is interested in the potential of F10 for improved treatment of prostate cancer based upon...displays strong anti-cancer activity and minimal systemic toxicity in pre-clinical models of AML and GBM and that in previous studies demonstrated...of the low toxicity and strong anti-cancer activity of F10 in animal models of AML and GBM this combination is likely to be effective and well

Selective Chemosensitization of Rb Mutant Cells

DTIC Science & Technology

2001-07-01

MA). pLPC-12S coexpresses an E1A 12S cDNA with puromycin phosphotransferase (puro) and pWZL-12S coexpresses E1A with hygromycin phospho...expressing puromycin phosphotransferase (puro); LPC-12S, a 12S El A cDNA in LPC (McCurrach et al. 1997); LPC-12S.AN and LPC-12S.ACR2, El A mutants that...2, -3, conserved regions 1, 2, and 3; MEF, mouse embryonic fibroblast; puro, puromycin; hygro, hygromycin . To whom reprint requests should be

The Role of Mitochondrial TCA Cycle Enzymes in Determining Prostate Cancer Chemosensitivity

DTIC Science & Technology

2014-03-01

phosphorylation, Nat Rev Genet 2, 342-352. 17. Higgins , L. H., Withers, H. G., Garbens, A., Love, H. D., Magnoni, L., Hayward, S. W., and Moyes, C. D. (2009...MalateDehydrogenase 2ConfersDocetaxel Resistancevia Regulations of JNKSignaling andOxidativeMetabolism Qiong Liu, Chris T. Harvey, Hao Geng, Changhui...1036 Liuet al. The Prostate 40. Higgins LH, Withers HG, Garbens A, Love HD, Magnoni L, Hayward SW, Moyes CD. Hypoxia and the metabolic pheno- type of

Biorelevant in vitro performance testing of orally administered dosage forms-workshop report.

PubMed

Reppas, Christos; Friedel, Horst-Dieter; Barker, Amy R; Buhse, Lucinda F; Cecil, Todd L; Keitel, Susanne; Kraemer, Johannes; Morris, J Michael; Shah, Vinod P; Stickelmeyer, Mary P; Yomota, Chikako; Brown, Cynthia K

2014-07-01

Biorelevant in vitro performance testing of orally administered dosage forms has become an important tool for the assessment of drug product in vivo behavior. An in vitro performance test which mimics the intraluminal performance of an oral dosage form is termed biorelevant. Biorelevant tests have been utilized to decrease the number of in vivo studies required during the drug development process and to mitigate the risk related to in vivo bioequivalence studies. This report reviews the ability of current in vitro performance tests to predict in vivo performance and generate successful in vitro and in vivo correlations for oral dosage forms. It also summarizes efforts to improve the predictability of biorelevant tests. The report is based on the presentations at the 2013 workshop, Biorelevant In Vitro Performance Testing of Orally Administered Dosage Forms, in Washington, DC, sponsored by the FIP Dissolution/Drug Release Focus Group in partnership with the American Association of Pharmaceutical Scientists (AAPS) and a symposium at the AAPS 2012 Annual meeting on the same topic.

76 FR 4113 - Independent Scientific Peer Review Panel Meeting on an In Vitro

Federal Register 2010, 2011, 2012, 2013, 2014

2011-01-24

... Vitro Estrogen Receptor Transcriptional Activation Test Method for Endocrine Disruptor Chemical... Vitro Estrogen Receptor Transcriptional Activation Test Method for Endocrine Disruptor Chemical... the information included in the BRD supports ICCVAM's draft test method recommendations. NICEATM...

49 CFR 173.137 - Class 8-Assignment of packing group.

Code of Federal Regulations, 2011 CFR

2011-10-01

... the Testing of Chemicals, Number 435, “In Vitro Membrane Barrier Test Method for Skin Corrosion” (IBR... Guideline for the Testing of Chemicals, Number 430, “In Vitro Skin Corrosion: Transcutaneous Electrical Resistance Test (TER)” (IBR, see § 171.7 of this subchapter) or Number 431, “In Vitro Skin Corrosion: Human...

49 CFR 173.137 - Class 8-Assignment of packing group.

Code of Federal Regulations, 2012 CFR

2012-10-01

... the Testing of Chemicals, Number 435, “In Vitro Membrane Barrier Test Method for Skin Corrosion” (IBR... Guideline for the Testing of Chemicals, Number 430, “In Vitro Skin Corrosion: Transcutaneous Electrical Resistance Test (TER)” (IBR, see § 171.7 of this subchapter) or Number 431, “In Vitro Skin Corrosion: Human...

A core in vitro genotoxicity battery comprising the Ames test plus the in vitro micronucleus test is sufficient to detect rodent carcinogens and in vivo genotoxins.

PubMed

Kirkland, David; Reeve, Lesley; Gatehouse, David; Vanparys, Philippe

2011-03-18

In vitro genotoxicity testing needs to include tests in both bacterial and mammalian cells, and be able to detect gene mutations, chromosomal damage and aneuploidy. This may be achieved by a combination of the Ames test (detects gene mutations) and the in vitro micronucleus test (MNvit), since the latter detects both chromosomal aberrations and aneuploidy. In this paper we therefore present an analysis of an existing database of rodent carcinogens and a new database of in vivo genotoxins in terms of the in vitro genotoxicity tests needed to detect their in vivo activity. Published in vitro data from at least one test system (most were from the Ames test) were available for 557 carcinogens and 405 in vivo genotoxins. Because there are fewer publications on the MNvit than for other mammalian cell tests, and because the concordance between the MNvit and the in vitro chromosomal aberration (CAvit) test is so high for clastogenic activity, positive results in the CAvit test were taken as indicative of a positive result in the MNvit where there were no, or only inadequate data for the latter. Also, because Hprt and Tk loci both detect gene-mutation activity, a positive Hprt test was taken as indicative of a mouse-lymphoma Tk assay (MLA)-positive, where there were no data for the latter. Almost all of the 962 rodent carcinogens and in vivo genotoxins were detected by an in vitro battery comprising Ames+MNvit. An additional 11 carcinogens and six in vivo genotoxins would apparently be detected by the MLA, but many of these had not been tested in the MNvit or CAvit tests. Only four chemicals emerge as potentially being more readily detected in MLA than in Ames+MNvit--benzyl acetate, toluene, morphine and thiabendazole--and none of these are convincing cases to argue for the inclusion of the MLA in addition to Ames+MNvit. Thus, there is no convincing evidence that any genotoxic rodent carcinogens or in vivo genotoxins would remain undetected in an in vitro test battery consisting of Ames+MNvit. Copyright © 2011 Elsevier B.V. All rights reserved.

Synergistic Interactions of Eugenol-tosylate and Its Congeners with Fluconazole against Candida albicans.

PubMed

Ahmad, Aijaz; Wani, Mohmmad Younus; Khan, Amber; Manzoor, Nikhat; Molepo, Julitha

2015-01-01

We previously reported the antifungal properties of a monoterpene phenol "Eugenol" against different Candida strains and have observed that the addition of methyl group to eugenol drastically increased its antimicrobial potency. Based on the results and the importance of medicinal synthetic chemistry, we synthesized eugenol-tosylate and its congeners (E1-E6) and tested their antifungal activity against different clinical fluconazole (FLC)- susceptible and FLC- resistant C. albicans isolates alone and in combination with FLC by determining fractional inhibitory concentration indices (FICIs) and isobolograms calculated from microdilution assays. Minimum inhibitory concentration (MIC) results confirmed that all the tested C. albicans strains were variably susceptible to the semi-synthetic derivatives E1-E6, with MIC values ranging from 1-62 μg/ml. The test compounds in combination with FLC exhibited either synergy (36%), additive (41%) or indifferent (23%) interactions, however, no antagonistic interactions were observed. The MICs of FLC decreased 2-9 fold when used in combination with the test compounds. Like their precursor eugenol, all the derivatives showed significant impairment of ergosterol biosynthesis in all C. albicans strains coupled with down regulation of the important ergosterol biosynthesis pathway gene-ERG11. The results were further validated by docking studies, which revealed that the inhibitors snugly fitting the active site of the target enzyme, mimicking fluconazole, may well explain their excellent inhibitory activity. Our results suggest that these compounds have a great potential as antifungals, which can be used as chemosensitizing agents with the known antifungal drugs.

40 CFR 798.5375 - In vitro mammalian cytogenetics.

Code of Federal Regulations, 2014 CFR

2014-07-01

... mammalian cytogenetics. (a) Purpose. The in vitro cytogenetics test is a mutagenicity test system for the... first post-treatment mitosis and numerical aberrations require at least one cell division to be... chromatids. (c) Reference substances. Not applicable. (d) Test method—(1) Principle. In vitro cytogenetics...

The current limitations of in vitro genotoxicity testing and their relevance to the in vivo situation.

PubMed

Nesslany, Fabrice

2017-08-01

The standard regulatory core battery of genotoxicity tests generally includes 2 or 3 validated tests with at least one in vitro test in bacteria and one in vitro test on cell cultures. However, limitations in in vitro genotoxicity testing may exist at many levels. The knowledge of the underlying mechanisms of genotoxicity is particularly useful to assess the level of relevance for the in vivo situation. In order to avoid wrong conclusions regarding the actual genotoxicity status of any test substance, it appears very important to be aware of the various origins of related bias leading to 'false positives and negatives' by using in vitro methods. Among these, mention may be made on the metabolic activation system, experimental (extreme) conditions, specificities of the test systems implemented, cell type used etc. The knowledge of the actual 'limits' of the in vitro test systems used is clearly an advantage and may contribute to avoid some pitfalls in order to better assess the level of relevance for the in vivo situation. Copyright © 2016. Published by Elsevier Ltd.

The value of detection of S100A8 and ASAH1 in predicting the chemotherapy response for breast cancer patients.

PubMed

Li, Yu-Hong; Liu, Hai-Ting; Xu, Jing; Xing, Ai-Yan; Zhang, Jie; Wang, Ya-Wen; Yin, Gang; Gao, Peng

2018-04-01

Chemotherapy plays an important role in the treatment of breast cancer. However, chemoresistance remains the main obstacle for effective treatment, leading to poor prognosis. This study aims to investigate the value of detection of S100A8 and ASAH1 in predicting the chemotherapy response. Miller and Payne grades were used to assess the chemotherapy response in breast cancers. The expression of S100A8 and ASAH1, as well as ER, PR, HER2 and Ki-67 were assessed by immunohistochemical staining in 120 cases of non-special type invasive ductal carcinoma (IDC-NOS). S100A8 expression was higher in chemosensitive breast cancers than chemoresistant ones. Moreover, S100A8 expression was significantly correlated with the molecular subtypes and histological grade, but not with patients' age, tumor size and lymph nodes status. However, there was no significant difference in ASAH1 expression between chemoresistant and chemosensitive group. We also found that higher ASAH1 expression was correlated with positive lymph nodes status, but not with age, tumor size, molecular subtypes and histological grade. S100A8 was valuable in predicting chemotherapy response in breast cancers. The expression of ASAH1 was associated significantly with lymph nodes metastasis, indicating that ASAH1 may serve as a biomarker to predict patients' lymph nodes status in breast cancers. Copyright © 2018 Elsevier Inc. All rights reserved.

Hispidulin inhibits proliferation and enhances chemosensitivity of gallbladder cancer cells by targeting HIF-1α

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

Gao, Hui; Xie, Jing; Peng, Jianjun, E-mail: jianjunpeng@126.com

2015-03-15

Gallbladder cancer (GBC) is an aggressive malignancy of the bile duct, which is associated with a low (5-year) survival and poor prognosis. The transcription factor HIF-1α is implicated in the angiogenesis, cell survival, epithelial mesenchymal transition (EMT) and invasiveness of GBC. In this study, we have investigated the role of HIF-1α in the pathobilogy of GBC and effect of hispidulin on the molecular events controlled by this transcription factor. We observed that hispidulin caused induction of apoptosis, blockade of growth and cell cycle progression in GBC cells. Our results have demonstrated for the first time that hispidulin-exerted anti-tumor effect involvedmore » the suppression of HIF-1α signaling. Hispidulin was found to repress the expression of HIF-1α protein dose-dependently without affecting the HIF-1α mRNA expression. In addition, the inhibition of HIF-1α protein synthesis was revealed to be mediated through the activation of AMPK signaling. Hispidulin also sensitized the tumor cells to Gemcitabine and 5-Fluoroucil by down-regulating HIF-1α/P-gp signaling. Given the low cost and exceedingly safe profile, hispidulin appears to be a promising and novel chemosensitizer for GBC treatment. - Highlights: • Hispidulin inhibits proliferation of gallbladder cancer cells by targeting HIF-1α. • Hispidulin regulates HIF-1α via activating AMPK signaling. • Hispidulin sensitized the GBC cells to chemotherapeutics by down-regulating P-gp.« less

Coadministration of the FNIII14 Peptide Synergistically Augments the Anti-Cancer Activity of Chemotherapeutic Drugs by Activating Pro-Apoptotic Bim

PubMed Central

Akari, Shougo; Otsuka, Kazuki; Fujita, Motomichi; Itagaki, Keisuke; Takizawa, You-ichi; Orita, Hiroaki; Owaki, Toshiyuki; Taira, Jyunichi; Hayashi, Ryo; Kodama, Hiroaki; Fukai, Fumio

2016-01-01

The acquisition of drug resistance mediated by the interaction of tumor cells with the extracellular matrix (ECM), commonly referred to as cell adhesion-mediated drug resistance (CAM-DR), has been observed not only in hematopoietic tumor cells but also in solid tumor cells. We have previously demonstrated that a 22-mer peptide derived from fibronectin, FNIII14, can inhibit cell adhesion through the inactivation of β1 integrin; when coadministered with cytarabine, FNIII14 completely eradicates acute myelogenous leukemia by suppressing CAM-DR. In this study, we show that our FNIII14 peptide also enhances chemotherapy efficacy in solid tumors. Coadministration of FNIII14 synergistically enhances the cytotoxicity of doxorubicin and aclarubicin in mammary tumor and melanoma cells, respectively. The solid tumor cell chemosensitization induced by FNIII14 is dependent upon the upregulation and activation of the pro-apoptotic protein, Bim. Furthermore, the metastasis of tumor cells derived from ventrally transplanted mammary tumor grafts is suppressed by the coadministration of FNIII14 and doxorubicin. These results suggest that the coadministration of our FNIII14 peptide with chemotherapy could achieve efficient solid tumor eradication by increasing chemosensitivity and decreasing metastasis. The major causes of tumor recurrence are the existence of chemotherapy-resistant primary tumor cells and the establishment of secondary metastatic lesions. As such, coadministering FNIII14 with anti-cancer drugs could provide a promising new approach to improve the prognosis of patients with solid tumors. PMID:27622612

Zoledronic acid overcomes chemoresistance and immunosuppression of malignant mesothelioma

PubMed Central

Kopecka, Joanna; Gazzano, Elena; Sara, Orecchia; Ghigo, Dario; Riganti, Chiara

2015-01-01

The human malignant mesothelioma (HMM) is characterized by a chemoresistant and immunosuppressive phenotype. An effective strategy to restore chemosensitivity and immune reactivity against HMM is lacking. We investigated whether the use of zoledronic acid is an effective chemo-immunosensitizing strategy. We compared primary HMM samples with non-transformed mesothelial cells. HMM cells had higher rate of cholesterol and isoprenoid synthesis, constitutive activation of Ras/extracellular signal-regulated kinase1/2 (ERK1/2)/hypoxia inducible factor-1α (HIF-1α) pathway and up-regulation of the drug efflux transporter P-glycoprotein (Pgp). By decreasing the isoprenoid supply, zoledronic acid down-regulated the Ras/ERK1/2/HIF-1α/Pgp axis and chemosensitized the HMM cells to Pgp substrates. The HMM cells also produced higher amounts of kynurenine, decreased the proliferation of T-lymphocytes and expanded the number of T-regulatory (Treg) cells. Kynurenine synthesis was due to the transcription of the indoleamine 1,2 dioxygenase (IDO) enzyme, consequent to the activation of the signal transducer and activator of transcription-3 (STAT3). By reducing the activity of the Ras/ERK1/2/STAT3/IDO axis, zoledronic acid lowered the kyurenine synthesis and the expansion of Treg cells, and increased the proliferation of T-lymphocytes. Thanks to its ability to decrease Ras/ERK1/2 activity, which is responsible for both Pgp-mediated chemoresistance and IDO-mediated immunosuppression, zoledronic acid is an effective chemo-immunosensitizing agent in HMM cells. PMID:25544757

The rostral medulla of bullfrog tadpoles contains critical lung rhythmogenic and chemosensitive regions across metamorphosis.

PubMed

Reed, Mitchell D; Iceman, Kimberly E; Harris, Michael B; Taylor, Barbara E

2018-06-08

The development of amphibian breathing provides insight into vertebrate respiratory control mechanisms. Neural oscillators in the rostral and caudal medulla drive ventilation in amphibians, and previous reports describe ventilatory oscillators and CO 2 sensitive regions arise during different stages of amphibian metamorphosis. However, inconsistent findings have been enigmatic, and make comparisons to potential mammalian counterparts challenging. In the current study we assessed amphibian central CO 2 responsiveness and respiratory rhythm generation during two different developmental stages. Whole-nerve recordings of respiratory burst activity in cranial and spinal nerves were made from intact or transected brainstems isolated from tadpoles during early or late stages of metamorphosis. Brainstems were transected at the level of the trigeminal nerve, removing rostral structures including the nucleus isthmi, midbrain, and locus coeruleus, or transected at the level of the glossopharyngeal nerve, removing the putative buccal oscillator and caudal medulla. Removal of caudal structures stimulated the frequency of lung ventilatory bursts and revealed a hypercapnic response in normally unresponsive preparations derived from early stage tadpoles. In preparations derived from late stage tadpoles, removal of rostral or caudal structures reduced lung burst frequency, while CO 2 responsiveness was retained. Our results illustrate that structures within the rostral medulla are capable of sensing CO 2 throughout metamorphic development. Similarly, the region controlling lung ventilation appears to be contained in the rostral medulla throughout metamorphosis. This work offers insight into the consistency of rhythmic respiratory and chemosensitive capacities during metamorphosis. Copyright © 2018. Published by Elsevier Inc.

shRNA-mediated EMMPRIN silencing inhibits human leukemic monocyte lymphoma U937 cell proliferation and increases chemosensitivity to adriamycin.

PubMed

Gao, Hui; Jiang, Qixiao; Han, Yantao; Peng, Jianjun; Wang, Chunbo

2015-03-01

EMMPRIN is a widely distributed cell surface glycoprotein, which plays an important role in tumor progression and confers resistance to some chemotherapeutic drugs. Recent studies have shown that EMMPRIN overexpression indicates poor prognosis in acute myeloid leukemia (AML). However, little was known on the role of EMMPRIN in leukemia. Human leukemia cell line U937 was stably transfected with a EMMPRIN-targeted shRNA-containing vector to investigate the effect of EMMPRIN on cellular functions. EMMPRIN expression was monitored by qRT-PCR and Western blotting. Cell viability and proliferation were determined by trypan blue exclusion and BrdU labeling, respectively. Cell cycle and apoptosis were analyzed by flow cytometry. Cytotoxicity of chemotherapeutic agent adriamycin on cells was assessed by MTT assay. Knockdown of EMMPRIN gene significantly inhibited cell viability and decreased cell proliferation. Fluorescence-activated cell-sorting analysis revealed that the reduced EMMPRIN expression resulted in cell cycle arrest at G1 phase and induced apoptosis. Meanwhile, western blotting analysis showed that EMMPRIN knockdown was associated with downregulation of cell cycle- and apoptosis-related molecules including cyclin D1, cyclin E, as well as increase in cleavage of caspase-3 and PARP. This study also showed that silencing of EMMPRIN sensitized U937 cells to Adriamycin. EMMPRIN is involved in proliferation, growth, and chemosensitivity of human AML line U937, indicating that EMMPRIN may be a promising therapeutic target for AML.

MicroRNA-451 sensitizes lung cancer cells to cisplatin through regulation of Mcl-1.

PubMed

Cheng, Dezhi; Xu, Yi; Sun, Changzheng; He, Zhifeng

2016-12-01

As one of the most widely used chemotherapy drugs for lung cancer, chemoresistance of cisplatin (DPP) is one of the major hindrances in treatment of this malignancy. The microRNAs (miRNAs) have been identified to mediate chemotherapy drug resistance. MiR-451 as a tumor suppressor has been evaluated its potential effect on the sensitivity of cancer cells to DDP. However, the role of miR-451 in regulatory mechanism of chemosensitivity in lung cancer cells is still largely unknown. In this study, we first constructed a cisplatin-resistant A549 cell line (A549/DPP) accompanied with a decreased expression of miR-451 and an increased expression of Mcl-1in the drug resistant cells compared with the parental cells. Exogenous expression of miR-451 level in A549/DPP was found to sensitize their reaction to the treatment of cisplatin, which coincides with reduced expression of Mcl-1. Interestingly, Mcl-1 knockdown in A549/DPP cells increased the chemosensitivity to DPP, suggesting the dependence of Mcl-1 regulation in miR-451 activity. Moreover, miR-451 can restore cisplatin treatment response in cisplatin-resistant xenografts in vivo, while Mcl-1 protein levels were decreased. Thus, these findings provided that in lung cancer cells, tumor suppressor miR-451 enhanced DPP sensitivity via regulation of Mcl-1 expression, which could be served as a novel therapeutic target for the treatment of chemotherapy resistant in lung cancer.

Mifepristone sensitizing cisplatin for cervical adenocarcinoma HeLa cell sensitivity to chemotherapy and its mechanism.

PubMed

Li, Caihong; Ye, Hong

2013-01-01

The study was designed to investigate proliferation inhibition for cervical adenocarcinoma HeLa cell treated with cisplatin combined with mifepristone and access its possible mechanism. HeLa cell was processed by different concentrations of mifepristone, cisplatin, and their combination respectively. Cell's proliferation inhibition rate and induction apoptosis ability were detected by MTT assay, FCM; the expression of P53, survivin and HPV E6 protein were measured by Western Blot. The results showed that cisplatin inhibits proliferation of HeLa cells in different concentrations (p <0.01). Mifepristone had no effect on HeLa cell proliferation inhibition rate during 24 and 48 hours (p > 0.05). Mifepristone at low concentrations (< or = 10 micromol/l) combined with cisplatin can significantly enhance the inhibitory effect of cisplatin on HeLa cell line. Flow cytometry showed that mifepristone at low concentrations (< or = 10 micromol/l) combined with cisplatin can induce apparent apoptosis of HeLa cell line in concentration dependent manner. Western blotting demonstrated that the expression of P53 protein increased and the expression of HPV E6 survivin protein decreased in HeLa cells treated with MIF at low concentrations (< or = 10 micromol/l) combined with cisplatin. Mifepristone at low concentrations (< or = 10 micromol/1) can enhance chemosensitivity and capability of inducing apoptosis of cisplatin to HeLa cells. The strengthening effect of growth inhibition and chemosensitivity to cisplatin of mifepristone are associated with down-regulating HPV E6 survivin protein and upregulating p53 protein.

Accelerated in-vitro release testing methods for extended-release parenteral dosage forms.

PubMed

Shen, Jie; Burgess, Diane J

2012-07-01

This review highlights current methods and strategies for accelerated in-vitro drug release testing of extended-release parenteral dosage forms such as polymeric microparticulate systems, lipid microparticulate systems, in-situ depot-forming systems and implants. Extended-release parenteral dosage forms are typically designed to maintain the effective drug concentration over periods of weeks, months or even years. Consequently, 'real-time' in-vitro release tests for these dosage forms are often run over a long time period. Accelerated in-vitro release methods can provide rapid evaluation and therefore are desirable for quality control purposes. To this end, different accelerated in-vitro release methods using United States Pharmacopeia (USP) apparatus have been developed. Different mechanisms of accelerating drug release from extended-release parenteral dosage forms, along with the accelerated in-vitro release testing methods currently employed are discussed. Accelerated in-vitro release testing methods with good discriminatory ability are critical for quality control of extended-release parenteral products. Methods that can be used in the development of in-vitro-in-vivo correlation (IVIVC) are desirable; however, for complex parenteral products this may not always be achievable. © 2012 The Authors. JPP © 2012 Royal Pharmaceutical Society.

Accelerated in vitro release testing methods for extended release parenteral dosage forms

PubMed Central

Shen, Jie; Burgess, Diane J.

2012-01-01

Objectives This review highlights current methods and strategies for accelerated in vitro drug release testing of extended release parenteral dosage forms such as polymeric microparticulate systems, lipid microparticulate systems, in situ depot-forming systems, and implants. Key findings Extended release parenteral dosage forms are typically designed to maintain the effective drug concentration over periods of weeks, months or even years. Consequently, “real-time” in vitro release tests for these dosage forms are often run over a long time period. Accelerated in vitro release methods can provide rapid evaluation and therefore are desirable for quality control purposes. To this end, different accelerated in vitro release methods using United States Pharmacopoeia (USP) apparatus have been developed. Different mechanisms of accelerating drug release from extended release parenteral dosage forms, along with the accelerated in vitro release testing methods currently employed are discussed. Conclusions Accelerated in vitro release testing methods with good discriminatory ability are critical for quality control of extended release parenteral products. Methods that can be used in the development of in vitro-in vivo correlation (IVIVC) are desirable, however for complex parenteral products this may not always be achievable. PMID:22686344

Transferability and inter-laboratory variability assessment of the in vitro bovine oocyte fertilization test.

PubMed

Tessaro, Irene; Modina, Silvia C; Crotti, Gabriella; Franciosi, Federica; Colleoni, Silvia; Lodde, Valentina; Galli, Cesare; Lazzari, Giovanna; Luciano, Alberto M

2015-01-01

The dramatic increase in the number of animals required for reproductive toxicity testing imposes the validation of alternative methods to reduce the use of laboratory animals. As we previously demonstrated for in vitro maturation test of bovine oocytes, the present study describes the transferability assessment and the inter-laboratory variability of an in vitro test able to identify chemical effects during the process of bovine oocyte fertilization. Eight chemicals with well-known toxic properties (benzo[a]pyrene, busulfan, cadmium chloride, cycloheximide, diethylstilbestrol, ketoconazole, methylacetoacetate, mifepristone/RU-486) were tested in two well-trained laboratories. The statistical analysis demonstrated no differences in the EC50 values for each chemical in within (inter-runs) and in between-laboratory variability of the proposed test. We therefore conclude that the bovine in vitro fertilization test could advance toward the validation process as alternative in vitro method and become part of an integrated testing strategy in order to predict chemical hazards on mammalian fertility. Copyright © 2015 Elsevier Inc. All rights reserved.

Effects of movement and work load in patients with congenital central hypoventilation syndrome.

PubMed

Hager, Alfred; Koch, Walter; Stenzel, Heike; Hess, John; Schöber, Johannes

2007-04-01

Patients with congenital central hypoventilation syndrome lack ventilatory chemosensitivity and depend at least in part on the ergoreceptor function during exercise. In these patients a substantial increase of ventilation has been reported for passive movement during sleep as well as active movement on a treadmill. The aim of the study was to investigate ventilatory response to an increasing work load with constant movement. Eighteen patients and 17 healthy volunteers performed a cardiopulmonary exercise test on a bicycle pedaling at a constant rate of about 60 revolutions per minute throughout the entire test. The patients were able to exercise adequately and showed normal peak oxygen uptake. There was a steep rise in minute ventilation in both groups at the start of exercise, yet there was only a minor increase in both groups during the increase of workload up to the anaerobic threshold. After the anaerobic threshold, there was again an increase in ventilation in both groups, but the increase was less prominent in the patient group. Ventilation in patients with congenital central hypoventilation syndrome is increased during exercise caused both by movement (mechanoreceptors) and by anaerobic workload. This facilitates a normal ventilatory drive up to the anaerobic threshold and a normal exercise capacity in these patients.

Evaluation of the Ortho-Clinical Diagnostics Vitros ECi Anti-HCV test: comparison with three other methods.

PubMed

Watterson, Jeannette M; Stallcup, Paulina; Escamilla, David; Chernay, Patrick; Reyes, Alfred; Trevino, Sylvia C

2007-01-01

After observing a high incidence of low positive hepatitis C virus (HCV) antibody screens by the Ortho-Clinical Vitros ECi test (Orthoclinical Diagnostics, Raritan, NJ), we compared results against those obtained using another chemiluminescent analyzer, as well as two U.S. Food and Drug Administration (FDA)-approved confirmatory methodologies. To ascertain the true anti-HCV status of samples deemed low-positive by the Ortho-Clinical Vitros ECi test, we tested samples using the ADVIA Centaur HCV screen test (Siemens Medical Solutions Diagnostics), the Chiron recombinant immunoblot assay (RIBA) test (Chiron Corp., Emeryville, CA), and the Roche COBAS Amplicor HCV qualitative test (Roche Diagnostics, Indianapolis, IN) in a series of studies. Of 94 specimens positive by Vitros ECi, 19% were observed to be negative by Centaur. A separate study of 91 samples with signal-to-cutoff (s/co) values less than 8.0 showed that all but one was negative for HCV ribonucleic acid (RNA). In comparison with RIBA, 100% (77) samples positive by the Vitros ECi test with s/co values less than 12.0 were negative or indeterminate by RIBA. A final study comparing all four methods side-by-side showed 63% disagreement by Centaur for Vitros ECi low-positive samples, 75% disagreement by RIBA, and 97% disagreement by polymerase chain reaction (PCR). In conclusion, the Ortho-Clinical Vitros ECi Anti-HCV test yields a high rate of false-positive results in the low s/co range in our patient population. (c) 2007 Wiley-Liss, Inc.

Applying fiber optical methods for toxicological testing in vitro

NASA Astrophysics Data System (ADS)

Maerz, Holger K.; Buchholz, Rainer; Emmrich, Frank; Fink, Frank; Geddes, Clive L.; Pfeifer, Lutz; Raabe, Ferdinand; Scheper, Thomas-Helmut; Ulrich, Elizabeth; Marx, Uwe

1999-04-01

The new medical developments, e.g. immune therapy, patient oriented chemotherapy or even gene therapy, create a questionable doubt to the further requirement of animal test. Instead the call for humanitarian reproductive in vitro models becomes increasingly louder. Pharmaceutical usage of in vitro has a long proven history. In cancer research and therapy, the effect of chemostatica in vitro in the so-called oncobiogram is being tested; but the assays do not always correlate with in vivo-like drug resistance and sensitivity. We developed a drug test system in vitro, feasible for therapeutic drug monitoring by the combination of tissue cultivation in hollow fiber bioreactors and fiber optic sensors for monitoring the pharmaceutical effect. Using two fiber optic sensors - an optical oxygen sensor and a metabolism detecting Laserfluoroscope, we were able to successfully monitor the biological status of tissue culture and the drug or toxic effects of in vitro pharmaceutical testing. Furthermore, we developed and patented a system for monitoring the effect of minor toxic compounds which can induce Sick Building Syndrome.

The CTFA Evaluation of Alternatives Program: an evaluation of in vitro alternatives to the Draize primary eye irritation test. (Phase III) surfactant-based formulations.

PubMed

Gettings, S D; Lordo, R A; Hintze, K L; Bagley, D M; Casterton, P L; Chudkowski, M; Curren, R D; Demetrulias, J L; Dipasquale, L C; Earl, L K; Feder, P I; Galli, C L; Glaza, S M; Gordon, V C; Janus, J; Kurtz, P J; Marenus, K D; Moral, J; Pape, W J; Renskers, K J; Rheins, L A; Roddy, M T; Rozen, M G; Tedeschi, J P; Zyracki, J

1996-01-01

The CTFA Evaluation of Alternatives Program is an evaluation of the relationship between data from the Draize primary eye irritation test and comparable data from a selection of promising in vitro eye irritation tests. In Phase III, data from the Draize test and 41 in vitro endpoints on 25 representative surfactant-based personal care formulations were compared. As in Phase I and Phase II, regression modelling of the relationship between maximum average Draize score (MAS) and in vitro endpoint was the primary approach adopted for evaluating in vitro assay performance. The degree of confidence in prediction of MAS for a given in vitro endpoint is quantified in terms of the relative widths of prediction intervals constructed about the fitted regression curve. Prediction intervals reflect not only the error attributed to the model but also the material-specific components of variation in both the Draize and the in vitro assays. Among the in vitro assays selected for regression modeling in Phase III, the relationship between MAS and in vitro score was relatively well defined. The prediction bounds on MAS were most narrow for materials at the lower or upper end of the effective irritation range (MAS = 0-45), where variability in MAS was smallest. This, the confidence with which the MAS of surfactant-based formulations is predicted is greatest when MAS approaches zero or when MAS approaches 45 (no comment is made on prediction of MAS > 45 since extrapolation beyond the range of observed data is not possible). No single in vitro endpoint was found to exhibit relative superiority with regard to prediction of MAS. Variability associated with Draize test outcome (e.g. in MAS values) must be considered in any future comparisons of in vivo and in vitro test results if the purpose is to predict in vivo response using in vitro data.

EFFECTS OF TREATMENTS ON SOIL-LEAD BIOAVAILABILITY: IMPLICATIONS OF IN-VITRO EXTRACTION TESTING

EPA Science Inventory

A field-scale study on the use of phosphate amendments to reduce lead bioavailabity from soil is being conducted at the Joplin site. One of the tools used to evaluate whether lead bioavailability is being reduced is an in vitro extraction test. The in vitro test simulates the gas...

In vitro testing of biological control agents on A1 and A2 isolates of Phytophthora ramorum

Treesearch

Marianne Elliott; Simon Shamoun

2008-01-01

Biological control products were tested in vitro with six isolates of Phytophthora ramorum. These isolates were geographically diverse and were selected based on their pathogenicity to detached Rhododendron leaves. In addition to five commercially available biocontrol products, nine species of Trichoderma were tested. The in vitro...

Wee1 Kinase Inhibitor AZD1775 Radiosensitizes Hepatocellular Carcinoma Regardless of TP53 Mutational Status Through Induction of Replication Stress

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

Cuneo, Kyle C., E-mail: kcuneo@umich.edu; Morgan, Meredith A.; Davis, Mary A.

2016-06-01

Purpose: Wee1 kinase inhibitors are effective radiosensitizers in cells lacking a G{sub 1} checkpoint. In this study we examined the potential effect of Wee1 kinase inhibition on inducing replication stress in hepatocellular carcinoma (HCC). Methods and Materials: Five independent datasets from the Oncomine database comparing gene expression in HCC compared to normal tissue were combined and specific markers associated with Wee1 sensitivity were analyzed. We then performed a series of in vitro experiments to study the effect of Wee1 inhibition on irradiated HCC cell lines with varying p53 mutational status. Clonogenic survival assays and flow cytometry using anti-γH2AX and phospho-histone H3more » antibodies with propidium iodide were performed to study the effect of AZD1775 on survival, cell cycle, and DNA repair. Additionally, nucleoside enriched medium was used to examine the effect of altering nucleotide pools on Wee1 targeted radiation sensitization. Results: Our analysis of the Oncomine database found high levels of CDK1 and other cell cycle regulators indicative of Wee1 sensitivity in HCC. In our in vitro experiments, treatment with AZD1775 radiosensitized and chemosensitized Hep3B, Huh7, and HepG2 cell lines and was associated with delayed resolution of γH2AX foci and the induction of pan-nuclear γH2AX staining. Wee1 inhibition attenuated radiation-induced G{sub 2} arrest in the Hep3B (TP53 null) and Huh7 (TP53 mutant) cell lines but not in the TP53 wild-type cell line HepG2. Supplementation with nucleosides reversed the radiation-sensitizing effect of AZD1775 and reduced the amount of cells with pan-nuclear γH2AX staining after radiation. Conclusions: Radiation sensitization with Wee1 inhibition occurs in cells regardless of their p53 mutational status. In this study we show for the first time that replication stress via the overconsumption of nucleotides plays an important role in AZD1775-induced radiation sensitization.« less

How to assess the mutagenic potential of cosmetic products without animal tests?

PubMed

Speit, Günter

2009-08-01

Animal experiments (in vivo tests) currently play a key role in genotoxicity testing. Results from in vivo tests are, in many cases, decisive for the assessment of a mutagenic potential of a test compound. The Seventh Amendment to the European Cosmetics Directive will, however, ban the European marketing of cosmetic/personal care products that contain ingredients that have been tested in animal experiments. If genotoxicity testing is solely based on the currently established in vitro tests, the attrition rate for chemicals used in cosmetic products will greatly increase due to irrelevant positive in vitro test results. There is urgent need for new and/or improved in vitro genotoxicity tests and for modified test strategies. Test strategies should consider all available information on chemistry of the test substance/the chemical class (e.g. SAR, metabolic activation and dermal adsorption). Test protocols for in vitro genotoxicity tests should be sensitive and robust enough to ensure that negative results can be accepted with confidence. It should be excluded that positive in vitro test results are due to high cytotoxicity or secondary genotoxic effects which may be thresholded and/or only occur under in vitro test conditions. Consequently, further research is needed to establish the nature of thresholds in in vitro assays and to determine the potential for incorporation of mode of action data into future risk assessments. New/improved tests have to be established and validated, considering the use of (metabolically competent) primary (skin) cells, 3D skin models and cells with defined capacity for metabolic activation (e.g. genetically engineered cell lines). The sensitivity and specificity of new and improved genotoxicity tests has to be determined by testing a battery of genotoxic and non-genotoxic chemicals. New or adapted international guidelines will be needed for these tests. The establishment of such a new genotoxicity testing strategy will take time and the new in vitro genotoxicity testing will become much more complex and will require greater mechanistic understanding to build a weight of evidence decision, which will be demanding and time-consuming. At present, no validated alternative methods for the follow-up of positive results from the standard genotoxicity battery are available and an appropriate evaluation of the mutagenic potential of cosmetic ingredients without animal experiments is therefore not possible in many cases.

Validation of an In Vitro Sun Protection Factor (SPF) method in blinded ring-testing.

PubMed

Pissavini, M; Tricaud, C; Wiener, G; Lauer, A; Contier, M; Kolbe, L; Trullás Cabanas, C; Boyer, F; Nollent, V; Meredith, E; Dietrich, E; Matts, P J

2018-04-20

The objective of this work was to investigate the utility of a new in vitro SPF test method in blinded ring-testing, against new ISO acceptance criteria. 24 blinded, commercial, emulsion-type, primary sunscreen products, covering the full range of labelled SPF in Europe (SPF6 - 50+), were tested by 3 test institutes using the current ISO24444:2010 In Vivo SPF Test Method and simultaneously by 3 separate test laboratories using a new candidate in vitro SPF test method, developed under the leadership of Cosmetics Europe (CE). The resulting relationship between in vitro SPF and in vivo SPF values was then compared with acceptance criteria developed recently by the International Standards (ISO) TC217 / WG7 Sun Protection Test Methods Working Group. Analysis of the mean inter-laboratory in vitro and mean inter-institute in vivo SPF values revealed a strong correlation between in vitro and in vivo values, with a Pearson correlation coefficient of r 2 =0.88 (p<0.0001), a slope of 1.01 and a non-significant intercept (-1.48; p=0.62). When these data were compared to the new ISO WG7 acceptance criteria, method bias was found to be extremely low and over 95% of the coupled data lay within the model "funnel" (defined by upper and lower confidence intervals). In conclusion, the results of blinded ring testing and comparison to new ISO WG7 acceptance criteria indicate that a new in vitro SPF test method meets (and exceeds) these minimum criteria and is an interesting candidate for possible deployment as an industry test methodology. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Design, Multicomponent Synthesis, and Anticancer Activity of a Focused Histone Deacetylase (HDAC) Inhibitor Library with Peptoid-Based Cap Groups.

PubMed

Krieger, Viktoria; Hamacher, Alexandra; Gertzen, Christoph G W; Senger, Johanna; Zwinderman, Martijn R H; Marek, Martin; Romier, Christophe; Dekker, Frank J; Kurz, Thomas; Jung, Manfred; Gohlke, Holger; Kassack, Matthias U; Hansen, Finn K

2017-07-13

In this work, we report the multicomponent synthesis of a focused histone deacetylase (HDAC) inhibitor library with peptoid-based cap groups and different zinc-binding groups. All synthesized compounds were tested in a cellular HDAC inhibition assay and an MTT assay for cytotoxicity. On the basis of their noteworthy activity in the cellular HDAC assays, four compounds were further screened for their inhibitory activity against recombinant HDAC1-3, HDAC6, and HDAC8. All four compounds showed potent inhibition of HDAC1-3 as well as significant inhibition of HDAC6 with IC 50 values in the submicromolar concentration range. Compound 4j, the most potent HDAC inhibitor in the cellular HDAC assay, revealed remarkable chemosensitizing properties and enhanced the cisplatin sensitivity of the cisplatin-resistant head-neck cancer cell line Cal27CisR by almost 7-fold. Furthermore, 4j almost completely reversed the cisplatin resistance in Cal27CisR. This effect is related to a synergistic induction of apoptosis as seen in the combination of 4j with cisplatin.

Gold-Containing Indoles as Anti-Cancer Agents that Potentiate the Cytotoxic Effects of Ionizing Radiation

PubMed Central

Craig, Sandra; Gao, Lei; Lee, Irene; Gray, Thomas; Berdis, Anthony J.

2012-01-01

This report describes the design and application of several distinct gold-containing indoles as anti-cancer agents. When used individually, all gold-bearing compounds display cytostatic effects against leukemia and adherent cancer cell lines. However, two gold-bearing indoles show unique behavior by increasing the cytotoxic effects of clinically relevant levels of ionizing radiation. Quantifying the amount of DNA damage demonstrates that each gold-indole enhances apoptosis by inhibiting DNA repair. Both Au(I)-indoles were tested for inhibitory effects against various cellular targets including thioredoxin reductase, a known target of several gold compounds, and various ATP-dependent kinases. While neither compound significantly inhibits the activity of thioreoxin reductase, both showed inhibitory effects against several kinases associated with cancer initiation and progression. The inhibition of these kinases provides a possible mechanism for the ability of these Au(I)-indoles potentiate the cytotoxic effects of ionizing radiation. Clinical applications of combining Au(I)-indoles with ionizing radiation are discussed as a new strategy to achieve chemosensitization of cancer cells. PMID:22289037

Spectroscopic imaging system for high-throughput viability assessment of ovarian spheroids or microdissected tumor tissues (MDTs) in a microfluidic chip

NASA Astrophysics Data System (ADS)

St-Georges-Robillard, A.; Masse, M.; Kendall-Dupont, J.; Strupler, M.; Patra, B.; Jermyn, M.; Mes-Masson, A.-M.; Leblond, F.; Gervais, T.

2016-02-01

There is a growing effort in the biomicrosystems community to develop a personalized treatment response assay for cancer patients using primary cells, patient-derived spheroids, or live tissues on-chip. Recently, our group has developed a technique to cut tumors in 350 μm diameter microtissues and keep them alive on-chip, enabling multiplexed in vitro drug assays on primary tumor tissue. Two-photon microscopy, confocal microscopy and flow cytometry are the current standard to assay tissue chemosensitivity on-chip. While these techniques provide microscopic and molecular information, they are not adapted for high-throughput analysis of microtissues. We present a spectroscopic imaging system that allows rapid quantitative measurements of multiple fluorescent viability markers simultaneously by using a liquid crystal tunable filter to record fluorescence and transmittance spectra. As a proof of concept, 24 spheroids composed of ovarian cancer cell line OV90 were formed in a microfluidic chip, stained with two live cell markers (CellTrackerTM Green and Orange), and imaged. Fluorescence images acquired were normalized to the acquisition time and gain of the camera, dark noise was removed, spectral calibration was applied, and spatial uniformity was corrected. Spectral un-mixing was applied to separate each fluorophore's contribution. We have demonstrated that rapid and simultaneous viability measurements on multiple spheroids can be achieved, which will have a significant impact on the prediction of a tumor's response to multiple treatment options. This technique may be applied as well in drug discovery to assess the potential of a drug candidate directly on human primary tissue.

NANOG regulates epithelial-mesenchymal transition and chemoresistance in ovarian cancer.

PubMed

Qin, Shan; Li, Yanfang; Cao, Xuexia; Du, Jiexian; Huang, Xianghua

2017-02-28

A key transcription factor associated with poor prognosis and resistance to chemotherapy in ovarian cancer is NANOG. However, the mechanism by which NANOG functions remains undefined. It has been suggested that epithelial-to-mesenchymal transition (EMT) also contributes to development of drug resistance in different cancers. We thus determined whether NANOG expression was associated with EMT and chemoresistance in epithelial ovarian cancer cells. NANOG expression was increased in epithelial ovarian cancer cell lines compared with its expression in normal epithelial ovarian cell lines. NANOG expression in SKOV-3 or OV2008 cells directly correlated with high expression of mesenchymal cell markers and inversely with low expression of epithelial cell marker. RNAi-mediated silencing of NANOG in SKOV-3 reversed the expression of mesenchymal cell markers and restored expression of E-cadherin. Reversibly, stable overexpression of NANOG in Moody cells increased expression of N-cadherin whereas down-regulating expression of E-cadherin, cumulatively indicating that NANOG plays an important role in maintaining the mesenchymal cell markers. Modulating NANOG expression did not have any effect on proliferation or colony formation. Susceptibility to cisplatin increased in SKOV-3 cells on down-regulating NANOG and reversible results were obtained in Moody cells post-overexpression of NANOG. NANOG silencing in SKOV-3 and OV2008 robustly attenuated in vitro migration and invasion. NANOG expression exhibited a biphasic pattern in patients with ovarian cancer and expression was directly correlated to chemoresistance retrospectively. Cumulatively, our data demonstrate that NANOG expression modulates chemosensitivity and EMT resistance in ovarian cancer. © 2017 The Author(s).

Efficacy of adjuvant chemotherapy for non-small cell lung cancer assessed by metastatic potential associated with ACTN4.

PubMed

Miura, Nami; Kamita, Masahiro; Kakuya, Takanori; Fujiwara, Yutaka; Tsuta, Koji; Shiraishi, Hideaki; Takeshita, Fumitaka; Ochiya, Takahiro; Shoji, Hirokazu; Huang, Wilber; Ohe, Yuichiro; Yamada, Tesshi; Honda, Kazufumi

2016-05-31

Although several clinical trials have demonstrated the benefits of platinum-combined adjuvant chemotherapy for resected non-small cell lung cancer (NSCLC), predictive biomarkers for the efficacy of such therapy have not yet been identified. Selection of patients with high metastatic ability in the early stage of non-small cell lung cancer (NSCLC) has the potential to predict clinical benefit of adjuvant chemotherapy (ADJ).In order to develop a predictive biomarker for efficacy of ADJ, we reanalyzed patient data using a public database enrolled by JBR.10, which was a clinical trial to probe the clinical benefits of ADJ in stage-IB/II patients with NSCLC. The patients who were enrolled by JBR.10 were classified into 2 subgroups according to expression of the ACTN4 transcript: ACTN4 positive (ACTN4 (+)) and ACTN4 negative (ACTN4 (-)). In the ACTN4 (+) group, overall survival (OS) was significantly higher in the ADJ subgroup compared with the observation subgroup (OBS), indicating a significant survival benefit of ADJ. However, no difference in OS was found between ADJ and OBS groups in ACTN4 (-). Although ACTN4 expression level did not correlate with the chemosensitivity of cancer cell lines for cytotoxic drugs, the metastatic potential of A549 lung adenocarcinoma cells was significantly reduced by ACTN4 shRNA in in vitro assays and in an animal transplantation model. The clinical and preclinical data suggested that ACTN4 is a potential predictive biomarker for efficacy of ADJ in stage-IB/II patients with NSCLC, by reflecting the metastatic potential of tumor cells.

Proteomic identification of 14-3-3ϵ as a linker protein between pERK1/2 inhibition and BIM upregulation in human osteosarcoma cells.

PubMed

Kim, Kyung Ok; Hsu, Anny C; Lee, Heon Goo; Patel, Neel; Chandhanayingyong, Chandhanarat; Hickernell, Thomas; Lee, Francis Young-In

2014-06-01

Despite advancements in multimodality chemotherapy, conventional cytotoxic treatments still remain ineffective for a subset of patients with aggressive metastatic or multifocal osteosarcoma. It has been shown that pERK1/2 inhibition enhances chemosensitivity to doxorubicin and promotes osteosarcoma cell death in vivo and in vitro. One of the pro-apoptotic mechanisms is upregulation of Bim by pERK1/2 inhibitors. To this end, we examined proteomic changes of 143B human osteosarcoma cells with and without treatment of PD98059, pERK1/2 inhibitor. Specifically, we identified 14-3-3ϵ protein as a potential mediator of Bim expression in response to inhibition of pERK1/2. We hypothesized that 14-3-3ϵ mediates upregulation of Bim expression after pERK1/2 inhibition. We examined the expression of Bim after silencing 14-3-3ϵ using siRNA. The 14-3-3ϵ gene silencing resulted in downregulation of Bim expression after PD98059 treatment. These data indicate that 14-3-3ϵ is required for Bim expression and that it has an anti-cancer effect under pERK1/2 inhibition in 143B cells. By playing an essential role upstream of Bim, 14-3-3ϵ may potentially be a coadjuvant factor synergizing the effect of pERK1/2 inhibitors in addition to conventional cytotoxic agents for more effective osteosarcoma treatments. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

miR-188-5p inhibits tumour growth and metastasis in prostate cancer by repressing LAPTM4B expression

PubMed Central

Zhang, Hongtuan; Qi, Shiyong; Zhang, Tao; Wang, Andi; Liu, Ranlu; Guo, Jia; Wang, Yuzhuo; Xu, Yong

2015-01-01

Elucidation of the molecular targets and pathways regulated by the tumour-suppressive miRNAs can shed light on the oncogenic and metastatic processes in prostate cancer (PCa). Using miRNA profiling analysis, we find that miR-188-5p was significantly down-regulated in metastatic PCa. Down-regulation of miR-188-5p is an independent prognostic factor for poor overall and biochemical recurrence-free survival. Restoration of miR-188-5p in PCa cells (PC-3 and LNCaP) significantly suppresses proliferation, migration and invasion in vitro and inhibits tumour growth and metastasis in vivo. We also find overexpression of miR-188-5p in PC-3 cells can significantly enhance the cells' chemosensitivity to adriamycin. LAPTM4B is subsequently identified as a direct target of miR-188-5p in PCa, and is found to be significantly over-expressed in PCa. Knockdown of LAPTM4B phenotypically copies miR-188-5p-induced phenotypes, whereas ectopic expression of LAPTM4B reverses the effects of miR-188-5p. We also find that restoration of miR-188-5p can inhibit the PI3K/AKT signaling pathway via the suppression of LAPTM4B. Taken together, this is the first report unveils that miR-188-5p acts as a tumour suppressor in PCa and may therefore serve as a useful therapeutic target for the development of new anticancer therapy. PMID:25714029

CXCR4/Let-7a Axis Regulates Metastasis and Chemoresistance of Pancreatic Cancer Cells Through Targeting HMGA2.

PubMed

Xiao, Guangfa; Wang, Xitao; Yu, Yaqun

2017-01-01

Pancreatic cancer cells (PCC) is one of the most risky cancers and gemcitabine (GEM) is the standard first-line drug for treating PCC. The PCC will develop drug resistance to GEM after a period of treatment. However, the detailed molecular mechanism of pathogenesis and drug resistance remains unresolved. we employed qRT-PCR and western blot to examine the expression level of CXCR4, let-7a and HMGA2. In addition, we used MTT assay to detect cell proliferation and transwell assay to measure migration and invasiveness. The expression level of epithelial marker E-cadherin and mesenthymal marker N-cadherin was detected by western blot. The apoptosis was determined using annexin V-FITC/PI apoptosis detection kit by flow cytometry. we first proved that CXCR4 negatively regulated let-7a in PCC. Next, let-7a was confirmed to play crucial role in tumorigenesis, metastasis and drug resistance of pancreatic cancer cells Bxpc-3 and Panc-1 in vitro and in vivo. Finally, we identified HMGA2 as important downsteam target of let-7a in PCC and overexpression of HMGA2 restores cell proliferation, metastasis and chemosensitivity of GEM inhibited by let-7a. Conlusion: Taken together, we show an important signaling pathway involved in pathogenesis and drug resistance of PCC, thereby providing deeper insight into molecular mechanism by which CXCR4/let-7a regulates tumorigenesis and drug resistance of PCC. These findings will help us develop new strategies for diagnosis and treatment of PCC. The Author(s). Published by S. Karger AG, Basel.

CD133 antisense suppresses cancer cell growth and increases sensitivity to cisplatin in vitro.

PubMed

Blancas-Mosqueda, Marisol; Zapata-Benavides, Pablo; Zamora-Ávila, Diana; Saavedra-Alonso, Santiago; Manilla-Muñoz, Edgar; Franco-Molina, Moisés; DE LA Peña, Carmen Mondragón; Rodríguez-Padilla, Cristina

2012-11-01

The increased incidence of cancer in recent years is associated with a high rate of mortality. Numerous types of cancer have a low percentage of CD133(+) cells, which have similar features to stem cells. The CD133 molecule is involved in apoptosis and cell proliferation. The aim of this study was to determine the biological effect of CD133 suppression and its role in the chemosensitization of cancer cell lines. RT-PCR and immunocytochemical analyses indicated that CD133 was expressed in the cancer cell lines B16F10, MCF7 and INER51. Downregulation of CD133 by transfection with an antisense sequence (As-CD133) resulted in a decrease in cancer cell viability of up to 52, 47 and 22% in B16F10, MCF-7 and INER51 cancer cell lines, respectively. This decreased viability appeared to be due to the induction of apoptosis. In addition, treatment with As-CD133 in combination with cisplatin had a synergic effect in all of the cancer cell lines analyzed, and in particular, significantly decreased the viability of B16F10 cancer cells compared with each treatment separately (3.1% viability for the combined treatment compared with 48% for 0.4 μg As-CD133 and 25% for 5 ng/μl cisplatin; P<0.05). The results indicate that the downregulation of CD133 by antisense is a potential therapeutic target for cancer and has a synergistic effect when administered with minimal doses of the chemotherapeutic drug cisplatin, suggesting that this combination strategy may be applied in cancer treatment.

G3139, an Anti-Bcl-2 Antisense Oligomer that Binds Heparin-Binding Growth Factors and Collagen I, Alters In Vitro Endothelial Cell Growth and Tubular Morphogenesis

PubMed Central

Stein, C.A.; Wu, SiJian; Voskresenskiy, Anatoliy M.; Zhou, Jin-Feng; Shin, Joongho; Miller, Paul; Souleimanian, Naira; Benimetskaya, Luba

2009-01-01

Purpose We examined the effects of G3139 on the interaction of heparin-binding proteins (e.g., FGF2 and collagen I) with endothelial cells. G3139 is an 18mer phosphorothioate oligonucleotide targeted to the initiation codon region of the Bcl-2 mRNA. A randomized, prospective global Phase III trial in advanced melanoma (GM301) has evaluted G3139 in combination with dacarbazine. However, the mechanism of action of G3139 is incompletely understood, as it is unlikely that Bcl-2 silencing is the sole mechanism for chemo-sensitization in melanoma cells. Experimental Design The ability of G3139 to interact with and protect heparin-binding proteins was quantitated. The effects of G3139 on the binding of FGF2 to high affinity cell surface receptors, and the induction of cellular mitogenesis and tubular morphogenesis in HMEC-1 and HUVEC cells were determined. Results G3139 binds with picomolar affinity to collagen I. By replacing heparin, the drug can potentiate the binding of FGF2 to FGFR1 IIIc, and it protects FGF from oxidation and from proteolysis. G3139 can increase endothelial cell mitogenesis and tubular morphogenesis of HMEC-1 cells in 3D collagen gels, increases the mitogenesis of HUVEC cells similarly, and induces vessel sprouts in the rat aortic ring model. Conclusions G3139 dramatically affects the behavior of endothelial cells. There may be a correlation between this observation and the treatment interaction with LDH observed clinically. PMID:19351753

Pharmacokinetics and antitumor efficacy of DSPE-PEG2000 polymeric liposomes loaded with quercetin and temozolomide: Analysis of their effectiveness in enhancing the chemosensitization of drug-resistant glioma cells

PubMed Central

HU, JUN; WANG, JUNJIE; WANG, GANG; YAO, ZHONGJUN; DANG, XIAOQIAN

2016-01-01

In the present study, a new type of DSPE-PEG2000 polymeric liposome for the brain-targeted delivery of poorly water-soluble anticancer drugs was successfully prepared and characterized. The nanoparticles were formed by the self-assembly of an amphiphilic polymer consisting of hydrophilic 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[methoxy(polyethylene glycol)-2000] (DSPE-PEG2000). These nanoliposomes served as a safe delivery platform for the simultaneous delivery of quercetin (QUE) and temozolomide (TMZ) to rat brains. The 2-in-1 PEG2000-DSPE nanoliposomes containing QUE and TMZ (QUE/TMZ-NLs) were rapidly taken up by the U87 glioma cells in vitro, whereas at the same concentrations, the amounts of the free drugs taken up were minimal. The QUE/TMZ-NLs showed an enhanced potency in the U87 cells and the TMZ-resistant U87 cells (U87/TR cells), possibly due to the high intracellular drug concentration and the subsequent drug release. In vivo biodistribution experiments revealed a significant accumulation of QUE/TMZ-NLs in the brain, with significantly increased plasma concentrations of QUE and TMZ, as well as delayed clearance in our rat model of glioma. The results were not so significant for the QUE-loaded nanoliposomes (QUE-NLs) and free TMZ. The findings of our study establish the DSPE-PEG2000 polymeric liposome as a novel and effective nanocarrier for enhancing drug delivery to brain tumors. PMID:26782731

Apigenin suppresses GLUT-1 and p-AKT expression to enhance the chemosensitivity to cisplatin of laryngeal carcinoma Hep-2 cells: an in vitro study

PubMed Central

Xu, Ying-Ying; Wu, Ting-Ting; Zhou, Shui-Hong; Bao, Yang-Yang; Wang, Qin-Ying; Fan, Jun; Huang, Ya-Ping

2014-01-01

Glucose transporter-1 (GLUT-1) and PI3K/Akt are known to be closely involved in resistance to chemotherapy. Co-targeted therapy reducing GLUT-1 expression and PI3K/Akt pathway activity may overcome the chemoresistance of human cancers. Apigenin may inhibit the expression of GLUT-1 and the PI3K/Akt pathway. We hypothesized that over-expression of GLUT-1 and p-Akt was associated with the resistance to cisplatin of laryngeal carcinoma Hep-2 cells. We explored whether apigenin inhibited GLUT-1 and p-Akt, resulting in sensitization of laryngeal carcinoma Hep-2 cells to cisplatin. Real-time RT-PCR and Western blotting confirmed the presence of GLUT-1 mRNA, and GLUT-1 and p-Akt proteins in Hep-2 cells. We found that resistance or insensitivity of Hep-2 cells to cisplatin might be associated with such expression. Apigenin markedly enhanced the cisplatin-induced suppression of Hep-2 cell growth. This effect was concentration- and time-dependent. Thus apigenin may significantly reduce the levels of GLUT-1 mRNA, and GLUT-1 and p-Akt proteins, in cisplatin-treated Hep-2 cells, in a concentration- and time-dependent manner. To conclude, overexpression of GLUT-1 mRNA may be associated with the resistance to cisplatin of laryngeal carcinoma Hep-2 cells. Apigenin may enhance the sensitivity to cisplatin of laryngeal carcinoma cells via inhibition of GLUT-1 and p-Akt expression. PMID:25120770

10 CFR 31.11 - General license for use of byproduct material for certain in vitro clinical or laboratory testing.

Code of Federal Regulations, 2010 CFR

2010-01-01

... in vitro clinical or laboratory testing. 31.11 Section 31.11 Energy NUCLEAR REGULATORY COMMISSION... certain in vitro clinical or laboratory testing. (a) A general license is hereby issued to any physician, veterinarian in the practice of veterinary medicine, clinical laboratory or hospital to receive, acquire...

9 CFR 113.8 - In vitro tests for serial release.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false In vitro tests for serial release. 113... REQUIREMENTS Applicability § 113.8 In vitro tests for serial release. (a) Master Seed which has been established as pure, safe, and immunogenic shall be used for preparing seed for production as specified in the...

Absorbable magnesium-based stent: physiological factors to consider for in vitro degradation assessments

PubMed Central

Wang, Juan; Smith, Christopher E.; Sankar, Jagannathan; Yun, Yeoheung; Huang, Nan

2015-01-01

Absorbable metals have been widely tested in various in vitro settings using cells to evaluate their possible suitability as an implant material. However, there exists a gap between in vivo and in vitro test results for absorbable materials. A lot of traditional in vitro assessments for permanent materials are no longer applicable to absorbable metallic implants. A key step is to identify and test the relevant microenvironment and parameters in test systems, which should be adapted according to the specific application. New test methods are necessary to reduce the difference between in vivo and in vitro test results and provide more accurate information to better understand absorbable metallic implants. In this investigative review, we strive to summarize the latest test methods for characterizing absorbable magnesium-based stent for bioabsorption/biodegradation behavior in the mimicking vascular environments. Also, this article comprehensively discusses the direction of test standardization for absorbable stents to paint a more accurate picture of the in vivo condition around implants to determine the most important parameters and their dynamic interactions. PMID:26816631

40 CFR 799.9537 - TSCA in vitro mammalian chromosome aberration test.

Code of Federal Regulations, 2014 CFR

2014-07-01

... aberration test. 799.9537 Section 799.9537 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... MIXTURE TESTING REQUIREMENTS Health Effects Test Guidelines § 799.9537 TSCA in vitro mammalian chromosome aberration test. (a) Scope—(1) Applicability. This section is intended to meet testing requirements under...

A synthetic cryptochrome inhibitor induces anti-proliferative effects and increases chemosensitivity in human breast cancer cells

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

Chun, Sung Kook; Department of Biological Sciences, Seoul National University, Seoul, 151-747; Department of Brain & Cognitive Sciences, Seoul National University, Seoul, 151-747

Disruption of circadian rhythm is a major cause of breast cancer in humans. Cryptochrome (CRY), a circadian transcription factor, is a risk factor for initiation of breast cancer, and it is differentially expressed between normal and breast cancer tissues. Here, we evaluated the anti-proliferative and pro-apoptotic activity of KS15, a recently discovered small-molecule inhibitor of CRY, in human breast cancer cells. First, we investigated whether KS15 treatment could promote E-box-mediated transcription by inhibiting the activity of CRY in MCF-7 human breast cancer cells. Protein and mRNA levels of regulators of cell cycle and apoptosis, as well as core clock genes,more » were differentially modulated in response to KS15. Next, we investigated whether KS15 could inhibit proliferation and increase sensitivity to anti-tumor drugs in MCF-7 cells. We found that KS15 decreased the speed of cell growth and increased the chemosensitivity of MCF-7 cells to doxorubicin and tamoxifen, but had no effect on MCF-10A cells. These findings suggested that pharmacological inhibition of CRY by KS15 exerts an anti-proliferative effect and increases sensitivity to anti-tumor drugs in a specific type of breast cancer. - Highlights: • Cryptochrome inhibitor (KS15) has anti-tumor activity to human breast cancer cells. • KS15 induces differential changes in cell cycle regulators and pro-apoptotic genes. • KS15 inhibits MCF-7 cell growth and enhances susceptibility to anti-tumor drugs.« less

Acquisition of relative interstrand crosslinker resistance and PARP inhibitor sensitivity in Fanconi anemia head and neck cancers

PubMed Central

Lombardi, Anne J.; Hoskins, Elizabeth E.; Foglesong, Grant D.; Wikenheiser-Brokamp, Kathryn A.; Wiesmüller, Lisa; Hanenberg, Helmut; Andreassen, Paul R.; Jacobs, Allison J.; Olson, Susan B.; Keeble, Winifred W.; Hays, Laura E.; Wells, Susanne I.

2015-01-01

Purpose Fanconi anemia (FA) is an inherited disorder associated with a constitutional defect in the FA DNA repair machinery that is essential for resolution of DNA interstrand crosslinks. Individuals with FA are predisposed to formation of head and neck squamous cell carcinomas (HNSCCs) at a young age. Prognosis is poor, partly due to patient intolerance of chemotherapy and radiation requiring dose reduction, which may lead to early recurrence of disease. Experimental Design Using HNSCC cell lines derived from the tumors of FA patients, and murine HNSCC cell lines derived from the tumors of wild type and Fancc−/− mice, we sought to define FA-dependent chemosensitivity and DNA repair characteristics. We utilized DNA repair reporter assays to explore the preference of FA HNSCC cells for non-homologous end joining (NHEJ). Results Surprisingly, interstrand crosslinker (ICL) sensitivity was not necessarily FA-dependent in human or murine cell systems. Our results suggest that the increased Ku-dependent NHEJ that is expected in FA cells did not mediate relative ICL resistance. ICL exposure resulted in increased DNA damage sensing and repair by poly(ADP-ribose) polymerase (PARP) in FA-deficient cells. Moreover, human and murine FA HNSCC cells were sensitive to PARP inhibition, and sensitivity of human cells was attenuated by FA gene complementation. Conclusions The observed reliance upon PARP-mediated mechanisms reveals a means by which FA HNSCCs can acquire relative resistance to the ICL-based chemotherapy that is a foundation of HNSCC treatment, as well as a potential target for overcoming chemoresistance in the chemosensitive individual. PMID:25609062

Inhibition of P-glycoprotein and glutathione S-transferase-pi mediated resistance by fluoxetine in MCF-7/ADM cells.

PubMed

Zhang, Ye; Zhou, Ting; Duan, Jingjing; Xiao, Zhijun; Li, Guihua; Xu, Feng

2013-10-01

Chemotherapy is important in the systematic treatment of breast cancer. While multidrug resistance (MDR) is the main obstacle in chemotherapy, a reversal reagent with high reversal effect but low toxicity is the hotspot issue at present to overcome MDR. Antidepressant fluoxetine (FLX) is a potential new highly effective chemosensitizer, however, the possible mechanism is unclear. In this study, the effect of FLX on multidrug resistance mediated by P-glycoprotein (P-gp) and glutathione S-transferase-pi (GST-π) were researched in resistant/sensitive breast cancer cells. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) was used to determine the cells viability after being incubated with FLX/Adriamycin (ADM)/Paclitaxel (PTX) alone or FLX-ADM, FLX-PTX combination. Western blot was performed to assay the expression of P-gp and GST-π proteins. Reverse transcriptase polymerase chain reaction (RT-PCR) and quantitative real-time PCR (qRT-PCR) were performed to assay the level of MDR1 mRNA. The results showed that pre-treatment with FLX enhance cytotoxicity significantly both on resistant and sensitive cells, downregulated the expression of P-gp and GST-π proteins in resistance cells, decreased the MDR1 mRNA by FLX-PTX combination only. No P-gp and GST-π were detected in sensitive cells. Our research thus indicated that FLX reverse the breast cancer cell's resistance and enhance the chemosensitivity by regulating P-gp and GST-π levels. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

Differential chemosensitization of P-glycoprotein overexpressing K562/Adr cells by withaferin A and Siamois polyphenols

PubMed Central

2010-01-01

Background Multidrug resistance (MDR) is a major obstacle in cancer treatment and is often the result of overexpression of the drug efflux protein, P-glycoprotein (P-gp), as a consequence of hyperactivation of NFκB, AP1 and Nrf2 transcription factors. In addition to effluxing chemotherapeutic drugs, P-gp also plays a specific role in blocking caspase-dependent apoptotic pathways. One feature that cytotoxic treatments of cancer have in common is activation of the transcription factor NFκB, which regulates inflammation, cell survival and P-gp expression and suppresses the apoptotic potential of chemotherapeutic agents. As such, NFκB inhibitors may promote apoptosis in cancer cells and could be used to overcome resistance to chemotherapeutic agents. Results Although the natural withanolide withaferin A and polyphenol quercetin, show comparable inhibition of NFκB target genes (involved in inflammation, angiogenesis, cell cycle, metastasis, anti-apoptosis and multidrug resistance) in doxorubicin-sensitive K562 and -resistant K562/Adr cells, only withaferin A can overcome attenuated caspase activation and apoptosis in K562/Adr cells, whereas quercetin-dependent caspase activation and apoptosis is delayed only. Interestingly, although withaferin A and quercetin treatments both decrease intracellular protein levels of Bcl2, Bim and P-Bad, only withaferin A decreases protein levels of cytoskeletal tubulin, concomitantly with potent PARP cleavage, caspase 3 activation and apoptosis, at least in part via a direct thiol oxidation mechanism. Conclusions This demonstrates that different classes of natural NFκB inhibitors can show different chemosensitizing effects in P-gp overexpressing cancer cells with impaired caspase activation and attenuated apoptosis. PMID:20438634

MEG3 is a prognostic factor for CRC and promotes chemosensitivity by enhancing oxaliplatin-induced cell apoptosis.

PubMed

Li, Lixia; Shang, Jian; Zhang, Yupeng; Liu, Shi; Peng, Yanan; Zhou, Zhou; Pan, Huaqing; Wang, Xiaobing; Chen, Lipng; Zhao, Qiu

2017-09-01

A major reason for the failure of advanced colorectal cancer (CRC) treatment is the occurrence of chemoresistance to oxaliplatin-based chemotherapy. Recently, studies have shown that long non-coding RNAs (lncRNAs) play an important role in drug resistance. Using HiSeq sequencing methods, we identified that lncRNAs show differential expression levels in oxaliplatin-resistant (OxR) and non-resistant CRC patients. RT-qPCR was then performed in tissues and serum samples, and lncRNA MEG3 was verified to be downregulated in non-responding patients and to have considerable discriminating potential to identify responding patients from non-responding patients. Moreover, decreased serum MEG3 expression was associated with poor chemoresponse and low survival rate in CRC patients receiving oxaliplatin treatment. Subsequently, OxR cell lines were established, and MEG3 was significantly downregulated in HT29 OxR and SW480 OxR cells. In addition, overexpression of MEG3 with pMEG3 reversed oxaliplatin resistance in both CRC cell lines. Flow cytometric apoptosis analysis indicated that MEG3 promoted CRC cell apoptosis. More importantly, MEG3 enhanced oxaliplatin‑induced cell cytotoxicity in CRC. In conclusion, our integrated approach demonstrated that decreased expression of lncRNA MEG3 in CRC confers potent poor therapeutic efficacy, and that MEG3 promotes chemosensitivity by enhancing oxaliplatin-induced cell apoptosis. Thus, overexpression of MEG3 may be a future direction by which to develop a novel therapeutic strategy to overcome oxaliplatin resistance of CRC patients.

Flow cytometric chemosensitivity assay using JC‑1, a sensor of mitochondrial transmembrane potential, in acute leukemia.

PubMed

Yokosuka, Tomoko; Goto, Hiroaki; Fujii, Hisaki; Naruto, Takuya; Takeuchi, Masanobu; Tanoshima, Reo; Kato, Hiromi; Yanagimachi, Masakatsu; Kajiwara, Ryosuke; Yokota, Shumpei

2013-12-01

The purpose of the study is to establish a simple and relatively inexpensive flow cytometric chemosensitivity assay (FCCA) for leukemia to distinguish leukemic blasts from normal leukocytes in clinical samples. We first examined whether the FCCA with the mitochondrial membrane depolarization sensor, 5, 50, 6, 60-tetrachloro-1, 10, 3, 30 tetraethyl benzimidazolo carbocyanine iodide (JC-1), could detect drug-induced apoptosis as the conventional FCCA by annexin V/7-AAD detection did and whether it was applicable in the clinical samples. Second, we compared the results of the FCCA for prednisolone (PSL) with clinical PSL response in 18 acute lymphoblastic leukemia (ALL) patients to evaluate the reliability of the JC-1 FCCA. Finally, we performed the JC-1 FCCA for bortezomib (Bor) in 25 ALL or 11 acute myeloid leukemia (AML) samples as the example of the clinical application of the FCCA. In ALL cells, the results of the JC-1 FCCA for nine anticancer drugs were well correlated with those of the conventional FCCA using anti-annexin V antibody (P < 0.001). In the clinical samples from 18 children with ALL, the results of the JC-1 FCCA for PSL were significantly correlated with the clinical PSL response (P = 0.005). In ALL samples, the sensitivity for Bor was found to be significantly correlated with the sensitivity for PSL (P = 0.005). In AML samples, the Bor sensitivity was strongly correlated with the cytarabine sensitivity (P = 0.0003). This study showed the reliability of a relatively simple and the FCCA using JC-1, and the possibility for the further clinical application.

Allogeneic Transplantation for Relapsed Waldenström Macroglobulinemia and Lymphoplasmacytic Lymphoma

PubMed Central

Cornell, Robert F.; Bachanova, Veronika; D'Souza, Anita; Woo-Ahn, Kwang; Martens, Michael; Huang, Jiaxing; Al-Homsi, A. Samer; Chhabra, Saurabh; Copelan, Edward; Diaz, Miguel-Angel; Freytes, Cesar O.; Gale, Robert Peter; Ganguly, Siddhartha; Hamadani, Mehdi; Hildebrandt, Gerhard; Kamble, Rammurti T.; Kharfan-Dabaja, Mohamed; Kindwall-Keller, Tamila; Lazarus, Hillard M.; Marks, David I.; Nishihori, Taiga; Olsson, Richard F.; Saad, Ayman; Usmani, Saad; Vesole, David H.; Yared, Jean; Mark, Tomer; Nieto, Yago; Hari, Parameswaran

2016-01-01

Waldenström macroglobulinemia/lymphoplasmacytic lymphoma (WM/LPL) is characterized by lymphoplasmacytic proliferation, lymph node and spleen enlargement, bone marrow involvement, and immunoglobulin M production. Treatment varies based on the extent and biology of disease. In some patients, the use of allogeneic hematopoietic cell transplantation (alloHCT) may have curative potential. We evaluated long-term outcomes of 144 patients that received adult alloHCT for WM/LPL. Data was obtained from the Center for International Blood and Marrow Transplant Research database (2001-2013). Patients received myeloablative (n=67) or reduced intensity conditioning (RIC; n=67). Median age at alloHCT was 53 years, and median time from diagnosis to transplantation was 41 months. Thirteen percent (n=18) failed prior autologous hematopoietic cell transplantation. About half (n=82, 57%) had chemo-sensitive disease at the time of transplantation, while 22% had progressive disease. Progression free survival, overall survival, rate of relapse, and non-relapse mortality at 5-years were 46%, 52%, 24%, and 30% respectively. Patients with chemo-sensitive disease and better pre-transplant disease status experienced significantly superior overall survival. There were no significant differences in progression-free survival based on conditioning (myeloablative 50% vs. RIC 41%) or graft source. Conditioning intensity did not impact treatment-related mortality or relapse. The most common causes of death were primary disease and graft-versus-host disease (GVHD). AlloHCT yielded durable survival in select patients with WM/LPL. Strategies to reduce mortality from GVHD and post-transplant relapse are necessary to improve this approach. PMID:27789362

Metastatic non-gestational choriocarcinoma to the brain: a case report and proposed treatment recommendations.

PubMed

Duong, Jason; Ghanchi, Hammad; Miulli, Dan; Kahlon, Avneet

2018-04-17

Non-gestational choriocarcinoma (NGC) is a rare germ cell tumor, reported less than 0.6% of all gestational tumors, and has a poor prognosis when metastasized. NGC is even less reported with metastasis to the brain. Gestational choriocarcinoma (GC) when metastasized to the brain has a higher morbidity and mortality but has been known to be a chemosensitive and radiosensitive lesion, and NGC is chemoresistant with an even worse prognosis. Currently, there is no consensus for treatment for metastatic NGC to the brain. 66 year-old post-menopausal female presents with left upper extremity weakness more pronounced in her hand, and work up demonstrating a hemorrhagic lesion over the right frontal parietal lobe. Her metastatic work up was negative, leading to a craniotomy for resection of the mass. The pathology was consistent with metastatic gestational choriocarcinoma, non-gestational in origin. Because of its chemosensitive nature, reports of optimal metastatic GC treatment include radiation alone, chemotherapy without radiation, surgical resection, or combined multimodal therapy. No recommendations for NGC metastatic to the brain have been reported. We propose a systematic work up for hemorrhagic brain lesions to include the proposed imaging modalities and serum markers including β-hCG to aid with early diagnosis. With review of literature, we recommend surgical resection with adjuvant therapy for accessible symptomatic metastatic GC and NGC to the brain for optimal patient outcomes. Chemotherapy and radiation alone without surgical resection can be considered for asymptomatic GC metastasis to the brain. Copyright © 2018 Elsevier Inc. All rights reserved.

Pathogenesis of Central and Complex Sleep Apnoea

PubMed Central

Orr, Jeremy E.; Malhotra, Atul; Sands, Scott A.

2016-01-01

Central sleep apnoea (CSA)—the temporary absence or diminution of ventilator effort during sleep—is seen in a variety of forms including periodic breathing in infancy and healthy adults at altitude and Cheyne-Stokes respiration in heart failure. In most circumstances, the cyclic absence of effort is paradoxically a consequence of hypersensitive ventilatory chemoreflex responses to oppose changes in airflow, i.e. elevated loop gain, leading to overshoot/undershoot ventilatory oscillations. Considerable evidence illustrates overlap between CSA and obstructive sleep apnoea (OSA), including elevated loop gain in patients with OSA and the presence of pharyngeal narrowing during central apnoeas. Indeed, treatment of OSA, whether via CPAP, tracheostomy, or oral appliances, can reveal CSA, an occurrence referred to as complex sleep apnoea. Factors influencing loop gain include increased chemosensitivity (increased controller gain), reduced damping of blood gas levels (increased plant gain) and increased lung to chemoreceptor circulatory delay. Sleep-wake transitions and pharyngeal dilator muscle responses effectively raise the controller gain and therefore also contribute to total loop gain and overall instability. In some circumstances, for example apnoea of infancy and central congenital hypoventilation syndrome, central apnoeas are the consequence of ventilatory depression and defective ventilatory responses, i.e. low loop gain. The efficacy of available treatments for CSA can be explained in terms of their effects on loop gain, e.g. CPAP improves lung volume (plant gain), stimulants reduce the alveolar-inspired PCO2 difference, supplemental oxygen lowers chemosensitivity. Understanding the magnitude of loop gain and the mechanisms contributing to instability may facilitate personalised interventions for CSA. PMID:27797160

Pathogenesis of central and complex sleep apnoea.

PubMed

Orr, Jeremy E; Malhotra, Atul; Sands, Scott A

2017-01-01

Central sleep apnoea (CSA) - the temporary absence or diminution of ventilatory effort during sleep - is seen in a variety of forms including periodic breathing in infancy and healthy adults at altitude and Cheyne-Stokes respiration in heart failure. In most circumstances, the cyclic absence of effort is paradoxically a consequence of hypersensitive ventilatory chemoreflex responses to oppose changes in airflow, that is elevated loop gain, leading to overshoot/undershoot ventilatory oscillations. Considerable evidence illustrates overlap between CSA and obstructive sleep apnoea (OSA), including elevated loop gain in patients with OSA and the presence of pharyngeal narrowing during central apnoeas. Indeed, treatment of OSA, whether via continuous positive airway pressure (CPAP), tracheostomy or oral appliances, can reveal CSA, an occurrence referred to as complex sleep apnoea. Factors influencing loop gain include increased chemosensitivity (increased controller gain), reduced damping of blood gas levels (increased plant gain) and increased lung to chemoreceptor circulatory delay. Sleep-wake transitions and pharyngeal dilator muscle responses effectively raise the controller gain and therefore also contribute to total loop gain and overall instability. In some circumstances, for example apnoea of infancy and central congenital hypoventilation syndrome, central apnoeas are the consequence of ventilatory depression and defective ventilatory responses, that is low loop gain. The efficacy of available treatments for CSA can be explained in terms of their effects on loop gain, for example CPAP improves lung volume (plant gain), stimulants reduce the alveolar-inspired PCO 2 difference and supplemental oxygen lowers chemosensitivity. Understanding the magnitude of loop gain and the mechanisms contributing to instability may facilitate personalized interventions for CSA. © 2016 Asian Pacific Society of Respirology.

Importance of dose intensity in neuro-oncology clinical trials: summary report of the Sixth Annual Meeting of the Blood-Brain Barrier Disruption Consortium.

PubMed

Doolittle, N D; Anderson, C P; Bleyer, W A; Cairncross, J G; Cloughesy, T; Eck, S L; Guastadisegni, P; Hall, W A; Muldoon, L L; Patel, S J; Peereboom, D; Siegal, T; Neuwelt, E A

2001-01-01

Therapeutic options for the treatment of malignant brain tumors have been limited, in part, because of the presence of the blood-brain barrier. For this reason, the Sixth Annual Meeting of the Blood-Brain Barrier Disruption Consortium, the focus of which was the "Importance of Dose Intensity in Neuro-Oncology Clinical Trials," was convened in April 2000, at Government Camp, Mount Hood, Oregon. This meeting, which was supported by the National Cancer Institute, the National Institute of Neurological Disorders and Stroke, and the National Institute of Deafness and Other Communication Disorders, brought together clinicians and basic scientists from across the U.S. to discuss the role of dose intensity and enhanced chemotherapy delivery in the treatment of malignant brain tumors and to design multicenter clinical trials. Optimizing chemotherapy delivery to the CNS is crucial, particularly in view of recent progress identifying certain brain tumors as chemosensitive. The discovery that specific constellations of genetic alterations can predict which tumors are chemoresponsive, and can therefore more accurately predict prognosis, has important implications for delivery of intensive, effective chemotherapy regimens with acceptable toxicities. This report summarizes the discussions, future directions, and key questions regarding dose-intensive treatment of primary CNS lymphoma, CNS relapse of systemic non-Hodgkin's lymphoma, anaplastic oligodendroglioma, high-grade glioma, and metastatic cancer of the brain. The promising role of cytoenhancers and chemoprotectants as part of dose-intensive regimens for chemosensitive brain tumors and development of improved gene therapies for malignant gliomas are discussed.

Inhibition of Survivin Influences the Biological Activities of Canine Histiocytic Sarcoma Cell Lines

PubMed Central

Hoshino, Yuki; Hosoya, Kenji; Okumura, Masahiro

2013-01-01

Canine histiocytic sarcoma (CHS) is an aggressive malignant neoplasm that originates from histiocytic lineage cells, including dendritic cells and macrophages, and is characterized by progressive local infiltration and a very high metastatic potential. Survivin is as an apoptotic inhibitory factor that has major functions in cell proliferation, including inhibition of apoptosis and regulation of cell division, and is expressed in most types of human and canine malignant neoplasms, including melanoma and osteosarcoma. To investigate whether survivin was expressed at high levels in CHS and whether its expression was correlated with the aggressive biological behavior of CHS, we assessed relation between survivin expression and CHS progression, as well as the effects of survivin inhibition on the biological activities of CHS cells. We comparatively analyzed the expression of 6 selected anti-apoptotic genes, including survivin, in specimens from 30 dogs with histiocytic sarcoma and performed annexin V staining to evaluate apoptosis, methylthiazole tetrazolium assays to assess cell viability and chemosensitivity, and latex bead assays to measure changes in phagocytic activities in 4 CHS cell lines and normal canine fibroblasts transfected with survivin siRNA. Survivin gene expression levels in 30 specimens were significantly higher than those of the other 6 genes. After transfection with survivin siRNA, apoptosis, cell growth inhibition, enhanced chemosensitivity, and weakened phagocytic activities were observed in all CHS cell lines. In contrast, normal canine fibroblasts were not significantly affected by survivin knockdown. These results suggested that survivin expression may mediate the aggressive biological activities of CHS and that survivin may be an effective therapeutic target for the treatment of CHS. PMID:24260303

Treatment of Peripheral T-Cell Lymphoma: Many Shades of Gray.

PubMed

Lunning, Matthew A

2015-08-01

Previously obscured within other designations of aggressive lymphomas, peripheral T-cell lymphoma (PTCL) now represents 23 different subtypes of non-Hodgkin lymphoma (NHL). Despite the many subtypes now recognized, PTCL represents only approximately 10% of all NHL cases diagnosed. Positron emission tomography/computed tomography has become essential to accurate staging and response-evaluation for PTCL. In comparison to aggressive B-cell NHL, patients with PTCL will more often be refractory to initial therapy, and chemosensitive patients will have shorter disease-free periods. Anthracycline-based regimens, often with the inclusion of etoposide, are commonly used during induction therapy. Consolidation with high-dose therapy and autologous stem cell transplantation (ASCT) in first chemosensitive remission appears to provide the best outcome in common nodal PTCL subtypes. The commonly defined nodal subtypes are PTCL not otherwise specified, angioimmunoblastic T-cell lymphoma, and anaplastic lymphoma kinase (ALK)-positive or ALK-negative anaplastic large-cell lymphoma (ALCL). Four agents have been approved by the US Food and Drug Administration for use in the relapsed/refractory (rel/ref) setting, including belinostat (2014), romidepsin (2011), brentuximab vedotin (2011), and pralatrexate (2009). Brentuximab vedotin was approved only for the ALCL subtype. These agents continue to be studied as combinations in the rel/ref setting and as additions or substitutions for other agents in upfront multiagent chemotherapy regimens. Patients who have responded to treatment in the rel/ref setting and are considered transplant-eligible should be considered for allogeneic stem cell transplantation, especially those with previous ASCT. Upfront allogeneic stem cell transplantation remains a research question in the majority of PTCL subtypes, but data are emerging.

Aurora kinase A has a significant role as a therapeutic target and clinical biomarker in endometrial cancer

PubMed Central

UMENE, KIYOKO; YANOKURA, MEGUMI; BANNO, KOUJI; IRIE, HARUKO; ADACHI, MASATAKA; IIDA, MIHO; NAKAMURA, KANAKO; NOGAMI, YUYA; MASUDA, KENTA; KOBAYASHI, YUSUKE; TOMINAGA, EIICHIRO; AOKI, DAISUKE

2015-01-01

Aurora kinase A (AURKA) regulates the cell cycle checkpoint and maintains genomic integrity. AURKA is overexpressed in various malignant tumors and its upregulation induces chromosomal instability, which leads to aneuploidy and cell transformation. To investigate the role of AURKA in endometrial cancer, we evaluated the association of immunohistochemical expression of AURKA with clinicopathological factors. Furthermore, we examined the effects of AURKA inhibition by transfected siRNA in HEC-1B cells on colony-forming ability, invasion and migration capacity, and chemosensitivity. Immunohistochemical staining showed that overexpression of AURKA was significantly associated with tumor grade (P<0.05) and poor histologic differentiation (P<0.05). The recurrence rate also tended to be high in cases with overexpression of AURKA (P<0.1) and these cases also had a tendency for shorter disease-free survival (DFS) (P<0.1). AURKA inhibition in endometrial cancer cell lines significantly decreased cell growth, invasion and migration (P<0.05), and increased chemosensitivity to paclitaxel. We also evaluated the efficacy of a combination of AURKA siRNA and paclitaxel against subcutaneous tumors formed in a nude mouse. After treatment, the tumor volume shrank significantly compared to treatment with paclitaxel only (P<0.05). To our knowledge, this is the first study in endometrial carcinoma to show a correlation between overexpression of AURKA and tumor grade, histological type and sensitivity to paclitaxel. AURKA is a promising therapeutic target in endometrial cancer and the combination therapy with AURKA inhibitors and paclitaxel could be effective for endometrial cancer that is resistant to conventional treatment and has a poor prognosis. PMID:25625960

Metformin enhances cisplatin induced inhibition of cholangiocarcinoma cells via AMPK-mTOR pathway.

PubMed

Wandee, Jaroon; Prawan, Auemduan; Senggunprai, Laddawan; Kongpetch, Sarinya; Tusskorn, Ornanong; Kukongviriyapan, Veerapol

2018-05-27

AMP-activated protein kinase (AMPK) functions as a cellular energy sensor regulating various aspects of cellular metabolism. Metformin (Met), an activator of AMPK, has been reported to reduce the cancer risk and enhance antitumor effects in certain cancers. Cholangiocarcinoma (CCA) is an aggressive malignancy which rarely responds to chemotherapeutic agents. We investigated the chemosensitizing effects of Met in CCA cells. KKU-100 and KKU-452 cells were used in the study. Antiproliferation of Met and cisplatin (Cis) was analyzed by sulforhodamine B and colony forming assays. Apoptotic cell death was analyzed by acridine orange and ethidium bromide staining method. Cell cycle analysis was performed by flow cytometric method. Effects on cell migration and invasion were analyzed by wound healing assay and transwell chamber method. Expression of proteins was examined by western blot analysis. Met enhanced the antiproliferation of Cis, and conferred antimigration and anti-invasion in CCA cells, where Cis alone did not have two latter effects. This chemosensitizing effect is related to the activation of AMPK and suppression of Akt, mTOR and p70S6K. Met and Cis increased expression of p53 and p21 and suppressed expression of cyclin D1. This effect was associated with cell cycle arrest at S phase. The anti-invasion effect was casually associated with the suppression of FAK expression. The cytotoxic effect of the drug combination was mimicked by AICAR, an AMPK agonist. Met may be a novel agent to increase the efficacy of Cis to treat CCA. Copyright © 2017. Published by Elsevier Inc.

Way forward in case of a false positive in vitro genotoxicity result for a cosmetic substance?

PubMed

Doktorova, Tatyana Y; Ates, Gamze; Vinken, Mathieu; Vanhaecke, Tamara; Rogiers, Vera

2014-02-01

The currently used regulatory in vitro mutagenicity/genotoxicity test battery has a high sensitivity for detecting genotoxicants, but it suffers from a large number of irrelevant positive results (i.e. low specificity) thereby imposing the need for additional follow-up by in vitro and/or in vivo genotoxicity tests. This could have a major impact on the cosmetic industry in Europe, seen the imposed animal testing and marketing bans on cosmetics and their ingredients. Afflicted, but safe substances could therefore be lost. Using the example of triclosan, a cosmetic preservative, we describe here the potential applicability of a human toxicogenomics-based in vitro assay as a potential mechanistically based follow-up test for positive in vitro genotoxicity results. Triclosan shows a positive in vitro chromosomal aberration test, but is negative during in vivo follow-up tests. Toxicogenomics analysis unequivocally shows that triclosan is identified as a compound acting through non-DNA reactive mechanisms. This proof-of-principle study illustrates the potential of genome-wide transcriptomics data in combination with in vitro experimentation as a possible weight-of-evidence follow-up approach for de-risking a positive outcome in a standard mutagenicity/genotoxicity battery. As such a substantial number of cosmetic compounds wrongly identified as genotoxicants could be saved for the future. Copyright © 2013 Elsevier Ltd. All rights reserved.

Neuronal models for evaluation of proliferation in vitro using high content screening

EPA Science Inventory

In vitro test methods can provide a rapid approach for the screening of large numbers of chemicals for their potential to produce toxicity (hazard identification). In order to identify potential developmental neurotoxicants, a battery of in vitro tests for neurodevelopmental proc...

Identification of a unique hepatocellular carcinoma line, Li-7, with CD13(+) cancer stem cells hierarchy and population change upon its differentiation during culture and effects of sorafenib.

PubMed

Yamada, Takeshi; Abei, Masato; Danjoh, Inaho; Shirota, Ryoko; Yamashita, Taro; Hyodo, Ichinosuke; Nakamura, Yukio

2015-04-11

Cancer stem cell (CSC) research has highlighted the necessity of developing drugs targeting CSCs. We investigated a hepatocellular carcinoma (HCC) cell line that not only has CSC hierarchy but also shows phenotypic changes (population changes) upon differentiation of CSC during culture and can be used for screening drugs targeting CSC. Based on a hypothesis that the CSC proportion should decrease upon its differentiation into progenitors (population change), we tested HCC cell lines (HuH-7, Li-7, PLC/PRF/5, HLF, HLE) before and after 2 months culture for several markers (CD13, EpCAM, CD133, CD44, CD90, CD24, CD166). Tumorigenicity was tested using nude mice. To evaluate the CSC hierarchy, we investigated reconstructivity, proliferation, ALDH activity, spheroid formation, chemosensitivity and microarray analysis of the cell populations sorted by FACS. Only Li-7 cells showed a population change during culture: the proportion of CD13 positive cells decreased, while that of CD166 positive cells increased. The high tumorigenicity of the Li-7 was lost after the population change. CD13(+)/CD166(-) cells showed slow growth and reconstructed the bulk Li-7 populations composed of CD13(+)/CD166(-), CD13(-)/CD166(-) and CD13(-)/CD166(+) fractions, whereas CD13(-)/CD166(+) cells showed rapid growth but could not reproduce any other population. CD13(+)/CD166(-) cells showed high ALDH activity, spheroid forming ability and resistance to 5-fluorouracil. Microarray analysis demonstrated higher expression of stemness-related genes in CD166(-) than CD166(+) fraction. These results indicated a hierarchy in Li-7 cells, in which CD13(+)/CD166(-) and CD13(-)/CD166(+) cells serve as slow growing CSCs and rapid growing progenitors, respectively. Sorafenib selectively targeted the CD166(-) fraction, including CD13(+) CSCs, which exhibited higher mRNA expression for FGF3 and FGF4, candidate biomarkers for sorafenib. 5-fluorouracil followed by sorafenib inhibited the growth of bulk Li-7 cells more effectively than the reverse sequence or either alone. We identified a unique HCC line, Li-7, which not only shows heterogeneity for a CD13(+) CSC hierarchy, but also undergoes a "population change" upon CSC differentiation. Sorafenib targeted the CSC in vitro, supporting the use of this model for screening drugs targeting the CSC. This type of "heterogeneous, unstable" cell line may prove more useful in the CSC era than conventional "homogeneous, stable" cell lines.

76 FR 20672 - Recommendations on In Vitro Ocular Safety Testing Methods and Strategies and Routine Use of...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-04-13

... certain regulatory testing purposes without the need for animal testing. The Organisation for Economic Co... DEPARTMENT OF HEALTH AND HUMAN SERVICES Recommendations on In Vitro Ocular Safety Testing Methods... Ocular Safety Testing AGENCY: National Institute of Environmental Health Sciences (NIEHS), National...

Informing Selection of Nanomaterial Concentrations for ToxCast In Vitro Testing using the Multi-Path Particle Dosimetry Model

EPA Science Inventory

Currently, little justification is provided for nanomaterial testing concentrations in in vitro assays. The in vitro concentrations typically used may be higher than those experienced in exposed humans. Selection of concentration levels for hazard evaluation based on real-world ...

Use of external metabolizing systems when testing for endocrine disruption in the T-screen assay

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

Taxvig, Camilla, E-mail: camta@food.dtu.dk; Olesen, Pelle Thonning; Nellemann, Christine

2011-02-01

Although, it is well-established that information on the metabolism of a substance is important in the evaluation of its toxic potential, there is limited experience with incorporating metabolic aspects into in vitro tests for endocrine disrupters. The aim of the current study was a) to study different in vitro systems for biotransformation of ten known endocrine disrupting chemicals (EDs): five azole fungicides, three parabens and 2 phthalates, b) to determine possible changes in the ability of the EDs to bind and activate the thyroid receptor (TR) in the in vitro T-screen assay after biotransformation and c) to investigate the endogenousmore » metabolic capacity of the GH3 cells, the cell line used in the T-screen assay, which is a proliferation assay used for the in vitro detection of agonistic and antagonistic properties of compounds at the level of the TR. The two in vitro metabolizing systems tested the human liver S9 mix and the PCB-induced rat microsomes gave an almost complete metabolic transformation of the tested parabens and phthalates. No marked difference the effects in the T-screen assay was observed between the parent compounds and the effects of the tested metabolic extracts. The GH3 cells themselves significantly metabolized the two tested phthalates dimethyl phthalate (DMP) and diethyl phthalate (DEP). Overall the results and qualitative data from the current study show that an in vitro metabolizing system using liver S9 or microsomes could be a convenient method for the incorporation of metabolic and toxicokinetic aspects into in vitro testing for endocrine disrupting effects.« less

Protein Binding: Do We Ever Learn?▿

PubMed Central

Zeitlinger, Markus A.; Derendorf, Hartmut; Mouton, Johan W.; Cars, Otto; Craig, William A.; Andes, David; Theuretzbacher, Ursula

2011-01-01

Although the influence of protein binding (PB) on antibacterial activity has been reported for many antibiotics and over many years, there is currently no standardization for pharmacodynamic models that account for the impact of protein binding of antimicrobial agents in vitro. This might explain the somewhat contradictory results obtained from different studies. Simple in vitro models which compare the MIC obtained in protein-free standard medium versus a protein-rich medium are prone to methodological pitfalls and may lead to flawed conclusions. Within in vitro test systems, a range of test conditions, including source of protein, concentration of the tested antibiotic, temperature, pH, electrolytes, and supplements may influence the impact of protein binding. As new antibiotics with a high degree of protein binding are in clinical development, attention and action directed toward the optimization and standardization of testing the impact of protein binding on the activity of antibiotics in vitro become even more urgent. In addition, the quantitative relationship between the effects of protein binding in vitro and in vivo needs to be established, since the physiological conditions differ. General recommendations for testing the impact of protein binding in vitro are suggested. PMID:21537013

Comparison of human skin irritation patch test data with in vitro skin irritation assays and animal data.

PubMed

Jírová, Dagmar; Basketter, David; Liebsch, Manfred; Bendová, Hana; Kejlová, Kristina; Marriott, Marie; Kandárová, Helena

2010-02-01

Efforts to replace the rabbit skin irritation test have been underway for many years, encouraged by the EU Cosmetics Directive and REACH. Recently various in vitro tests have been developed, evaluated and validated. A key difficulty in confirming the validity of in vitro methods is that animal data are scarce and of limited utility for prediction of human effects, which adversely impacts their acceptance. This study examines whether in vivo or in vitro data most accurately predicted human effects. Using the 4-hr human patch test (HPT) we examined a number of chemicals whose EU classification of skin irritancy is known to be borderline, or where in vitro methods provided conflicting results. Of the 16 chemicals classified as irritants in the rabbit, only five substances were found to be significantly irritating to human skin. Concordance of the rabbit test with the 4-hr HPT was only 56%, whereas concordance of human epidermis models with human data was 76% (EpiDerm) and 70% (EPISKIN). The results confirm observations that rabbits overpredict skin effects in humans. Therefore, when validating in vitro methods, all available information, including human data, should be taken into account before making conclusions about their predictive capacity.

Adaptive therapy.

PubMed

Gatenby, Robert A; Silva, Ariosto S; Gillies, Robert J; Frieden, B Roy

2009-06-01

A number of successful systemic therapies are available for treatment of disseminated cancers. However, tumor response is often transient, and therapy frequently fails due to emergence of resistant populations. The latter reflects the temporal and spatial heterogeneity of the tumor microenvironment as well as the evolutionary capacity of cancer phenotypes to adapt to therapeutic perturbations. Although cancers are highly dynamic systems, cancer therapy is typically administered according to a fixed, linear protocol. Here we examine an adaptive therapeutic approach that evolves in response to the temporal and spatial variability of tumor microenvironment and cellular phenotype as well as therapy-induced perturbations. Initial mathematical models find that when resistant phenotypes arise in the untreated tumor, they are typically present in small numbers because they are less fit than the sensitive population. This reflects the "cost" of phenotypic resistance such as additional substrate and energy used to up-regulate xenobiotic metabolism, and therefore not available for proliferation, or the growth inhibitory nature of environments (i.e., ischemia or hypoxia) that confer resistance on phenotypically sensitive cells. Thus, in the Darwinian environment of a cancer, the fitter chemosensitive cells will ordinarily proliferate at the expense of the less fit chemoresistant cells. The models show that, if resistant populations are present before administration of therapy, treatments designed to kill maximum numbers of cancer cells remove this inhibitory effect and actually promote more rapid growth of the resistant populations. We present an alternative approach in which treatment is continuously modulated to achieve a fixed tumor population. The goal of adaptive therapy is to enforce a stable tumor burden by permitting a significant population of chemosensitive cells to survive so that they, in turn, suppress proliferation of the less fit but chemoresistant subpopulations. Computer simulations show that this strategy can result in prolonged survival that is substantially greater than that of high dose density or metronomic therapies. The feasibility of adaptive therapy is supported by in vivo experiments. [Cancer Res 2009;69(11):4894-903] Major FindingsWe present mathematical analysis of the evolutionary dynamics of tumor populations with and without therapy. Analytic solutions and numerical simulations show that, with pretreatment, therapy-resistant cancer subpopulations are present due to phenotypic or microenvironmental factors; maximum dose density chemotherapy hastens rapid expansion of resistant populations. The models predict that host survival can be maximized if "treatment-for-cure strategy" is replaced by "treatment-for-stability." Specifically, the models predict that an optimal treatment strategy will modulate therapy to maintain a stable population of chemosensitive cells that can, in turn, suppress the growth of resistant populations under normal tumor conditions (i.e., when therapy-induced toxicity is absent). In vivo experiments using OVCAR xenografts treated with carboplatin show that adaptive therapy is feasible and, in this system, can produce long-term survival.

[Combined inhibition of STAT3 and HIF-1α for enhancement of chemosensitivity in the model of human laryngeal squamous cacinoma in nude mice].

PubMed

Lu, Xiuying; Li, Xiaoming; Song, Qi; Ma, Xiuru; Jia, Lifeng

2016-02-01

To investigate the effects of combined inhibition of signal transducer and activator of transcription 3 (STAT3) and hypoxia-inducible factor-1α (HIF-1α) in the enhancement of chemosensitivity of the model of human laryngeal squamous cacinoma in nude mice. Model nude mice were divided into six groups randomly: control group(A) , cisplatin group(B) , cisplatin and AG490 group(C) , cisplatin and HIF-1α⁻/⁻ group (D), cisplatin combined AG490 and HIF-1α⁻/⁻ group (E), HIF-1α⁻/⁻ group (F) (only in calculating tumor inhibition rate). 3mg/kg cisplatin was administered by peritoneal injection for 3 days. Then cisplatin and 10 mg/kg AG490 were administered every other day for 12 days. The expression of Ki67 and HIF-1α was detected by immunocytochemical method. Western blot was used to detect the expression of p-STAT3. The expression of HIF-1α in group C and group D were lower than that in group B, and there were significant difference respectively (t₁ = 2.782, t₂ = 3.873, P < 0.05); The expression of HIF-1α in group E was lower than that in group C and group D respectively, and there were significant difference respectively (t₁ = 6.140, t₂ = 3.667, P < 0.01). The expression level of p-STAT3 in group C was markedly lower compared with that in group B, and there were significant difference between them (t = 17.840, P < 0.01); There were no difference between the expression level of p-STAT3 in group D and that in group B (t = 0.038, P > 0.05); The expression level of p-STAT3 in group E was significantly lower compared with that in group C and group D respectively (P < 0.01). Tumor inhibition rate of group E was higher than that in group B, group C , as well as group D respectively and there were significant difference respectively (t₁ = 5.509, P < 0.01; t₂ = 3.422, P < 0.05; t₃ = 2.718, P < 0.05 ). Ki67 index of group E was lower than that in group B, group C as well as group D respectively and there were significant difference respectively(t₁ = 8.307, P < 0.01; t₂ = 3.736, P < 0.05; t₃ = 4.524, P < 0.01). Combined inhibition of STAT3 and HIF-1α could enhance chemo-sensitivity in the model of human laryngeal squamous cacinoma in nude mice.

10 CFR 32.71 - Manufacture and distribution of byproduct material for certain in vitro clinical or laboratory...

Code of Federal Regulations, 2010 CFR

2010-01-01

... certain in vitro clinical or laboratory testing under general license. 32.71 Section 32.71 Energy NUCLEAR... certain in vitro clinical or laboratory testing under general license. An application for a specific... only by physicians, veterinarians in the practice of veterinary medicine, clinical laboratories or...

Human Exposure Estimates and Oral Equivalents of In Vitro Bioactivity for Prioritizing, Monitoring and Testing of Environmental Chemicals

EPA Science Inventory

High-throughput, lower-cost, in vitro toxicity testing is currently being evaluated for use in prioritization and eventually for predicting in vivo toxicity. Interpreting in vitro data in the context of in vivo human relevance remains a formidable challenge. A key component in us...

In Vivo and In Vitro Nitinol Corrosion Properties

NASA Astrophysics Data System (ADS)

Lonn, Melissa K.; Metcalf, Justin M.; Choules, Brian D.

2015-09-01

Regulatory authorities often require in vitro testing on medical devices prior to approval. Current standardized corrosion testing methods (ASTM F2129) require testing in a non-physiologic, de-oxygenated solution for a pre-exposure time of ≤1 h; however, no correlations between the prescribed simulated environment and whole blood conditions have been elucidated. This study compared open circuit potential (OCP), breakdown potentials (Eb), Eb - OCP, and cyclic polarization curves tested in vivo (OCP only) and in vitro in whole blood to those tested in phosphate-buffered saline (PBS). Two oxide thicknesses of Nitinol, two solution oxygen contents (deaerated and aerated solutions), and two pre-exposure durations (acute and chronic) were investigated. The in vitro OCP in whole blood was not significantly different than the in vivo OCP, suggesting that whole blood in vitro can be used to determine baseline corrosion behavior of medical implants. Eb - OCP tested per ASTM F2129 was comparable to acute whole blood and was conservative compared to chronic whole blood for both oxide thicknesses. However, OCP, Eb, and cyclic polarization curves were not always comparable to whole blood. Testing in aerated PBS achieved Eb, Eb - OCP, and cyclic polarization curves that were comparable to or more conservative than whole blood testing, regardless of pre-exposure duration and oxide thickness.

40 CFR 799.9537 - TSCA in vitro mammalian chromosome aberration test.

Code of Federal Regulations, 2013 CFR

2013-07-01

... demonstrates the sensitivity of the test system. Positive control concentrations should be chosen so that the.... et al. Report from Working Group on In Vitro Tests for Chromosomal Aberrations. Mutation Research 312... aberration test. 799.9537 Section 799.9537 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY...

Use of external metabolizing systems when testing for endocrine disruption in the T-screen assay.

PubMed

Taxvig, Camilla; Olesen, Pelle Thonning; Nellemann, Christine

2011-02-01

Although, it is well-established that information on the metabolism of a substance is important in the evaluation of its toxic potential, there is limited experience with incorporating metabolic aspects into in vitro tests for endocrine disrupters. The aim of the current study was a) to study different in vitro systems for biotransformation of ten known endocrine disrupting chemicals (EDs): five azole fungicides, three parabens and 2 phthalates, b) to determine possible changes in the ability of the EDs to bind and activate the thyroid receptor (TR) in the in vitro T-screen assay after biotransformation and c) to investigate the endogenous metabolic capacity of the GH3 cells, the cell line used in the T-screen assay, which is a proliferation assay used for the in vitro detection of agonistic and antagonistic properties of compounds at the level of the TR. The two in vitro metabolizing systems tested the human liver S9 mix and the PCB-induced rat microsomes gave an almost complete metabolic transformation of the tested parabens and phthalates. No marked difference the effects in the T-screen assay was observed between the parent compounds and the effects of the tested metabolic extracts. The GH3 cells themselves significantly metabolized the two tested phthalates dimethyl phthalate (DMP) and diethyl phthalate (DEP). Overall the results and qualitative data from the current study show that an in vitro metabolizing system using liver S9 or microsomes could be a convenient method for the incorporation of metabolic and toxicokinetic aspects into in vitro testing for endocrine disrupting effects. Copyright © 2010 Elsevier Inc. All rights reserved.

Sunscreen tests: correspondence between in vitro data and values reported by the manufacturers.

PubMed

Garoli, Denis; Pelizzo, Maria Guglielmina; Bernardini, Bianca; Nicolosi, Piergiorgio; Alaibac, Mauro

2008-12-01

In vitro sunscreen tests are diffusively used to test both the sun protection factor (SPF) and the photo-stability of filters. Spectrophotometric measurements of the absorbance of ultraviolet radiations through a sunscreen applied on a suitable substrate allow a rapid evaluation of its protection factor both at short and long wavelength ultraviolet radiation (UVB and UVA). The objective of this study has been to demonstrate if Teflon can be adopted as substrate both for SPF evaluation and photo-stability tests. Moreover, we have investigated if there is a correspondence between in vitro SPF measurements and values reported by manufacturers on sunscreens. Teflon has been used to perform several photo-stability tests by irradiating the filters with different wavebands and analyzing the combined effect of UV and infrared (IR) light. Similar analyses have been carried out using PMMA Plates, which is the standard substrate for UVA in vitro test. We have demonstrated that it is possible to establish a good correspondence between in vitro SPF and values reported by manufacturers on sunscreens. We have also verified that the in vitro/label SPF correlation curve depends on the quantity of product applied while this does not seem to be true for other parameters like Critical Wavelength and UVA ratio. With regard to photo-stability studies, our results indicate for the first time that IR irradiation may have a role on photo-degradation. The results show that there is a good correlation between the in vitro SPF determined by the present method and the SPF reported by the manufacturer. The compatibility of the results obtained using Teflon and PMMA Plates demonstrates that Teflon can be utilized for both SPF determination and photo-stability tests.

78 FR 65338 - Agency Information Collection Activities; Submission for Office of Management and Budget Review...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-10-31

..., other clinical studies, or in vitro testing. Reports from animal testing are not included. \\3\\ Includes... serious risks from clinical trials within 15 calendar days for findings from in vitro testing that suggest...

A reassessment of the in vitro RBC haemolysis assay with defibrinated sheep blood for the determination of the ocular irritation potential of cosmetic products: comparison with the in vivo Draize rabbit test.

PubMed

Alves, Eloísa Nunes; Presgrave, Rosaura de Farias; Presgrave, Octávio Augusto França; Sabagh, Fernanda Peres; de Freitas, João Carlos Borges Rolim; Corrado, Alexandre P

2008-07-01

We examined the correlation between results obtained from the in vivo Draize test for ocular irritation and in vitro results obtained from the sheep red blood cell (RBC) haemolytic assay, which assesses haemolysis and protein denaturation in erythrocytes, induced by cosmetic products. We sought to validate the haemolytic assay as a preliminary test for identifying highly-irritative products, and also to evaluate the in vitro test as alternative assay for replacement of the in vivo test. In vitro and in vivo analyses were carried out on 19 cosmetic products, in order to correlate the lesions in the ocular structures with three in vitro parameters: (i) the extent of haemolysis (H50); (ii) the protein denaturation index (DI); and (iii) the H50/DI ratio, which reflects the irritation potential (IP). There was significant correlation between maximum average scores (MAS) and the parameters determined in vitro (r = 0.752-0.764). These results indicate that the RBC assay is a useful and rapid test for use as a screening method to assess the IP of cosmetic products, and for predicting the IP value with a high level of concordance (94.7%). The assay showed high sensitivity and specificity rates of 91.6% and 100%, respectively.

Lacking applicability of in vitro eye irritation methods to identify seriously eye irritating agrochemical formulations: Results of bovine cornea opacity and permeability assay, isolated chicken eye test and the EpiOcular™ ET-50 method to classify according to UN GHS.

PubMed

Kolle, Susanne N; Van Cott, Andrew; van Ravenzwaay, Bennard; Landsiedel, Robert

2017-04-01

In vitro methods have gained regulatory acceptance for the prediction of serious eye damage (UN GHS Cat 1). However, the majority of in vitro methods do not state whether they are applicable to agrochemical formulations. This manuscript presents a study of up to 27 agrochemical formulations tested in three in vitro assays (three versions of the bovine corneal opacity and permeability test (BCOP, OECD TG 437) assay, the isolated chicken eye test (ICE, OECD TG 438) and the EpiOcular™ ET-50 assay). The results were compared with already-available in vivo data. In the BCOP only one of the four, one of five in the ICE and six of eleven tested formulations in the EpiOcular™ ET-50 Neat Protocol resulted in the correct UN GHS Cat 1 prediction. Overpredictions occurred in all assays. These data indicate a lack of applicability of the three in vitro methods to reliably predict UN GHS Cat 1 of agrochemical formulations. In order to ensure animal-free identification of seriously eye damaging agrochemical formulations testing protocols and/or prediction models need to be modified or classification rules should be tailored to in vitro testing rather than using in vivo Draize data as a standard. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Clinical evaluation of Pharmacia CAP System RAST FEIA amoxicilloyl and benzylpenicilloyl in patients with penicillin allergy.

PubMed

Blanca, M; Mayorga, C; Torres, M J; Reche, M; Moya, M C; Rodriguez, J L; Romano, A; Juarez, C

2001-09-01

The diagnosis of IgE-mediated immediate reactions to penicillins can be supported by in vivo or in vitro tests using classical benzylpenicillin determinants. The wide variety of beta-lactams and the description of new specificities requires a re-evaluation of the different tests available. The objective was to evaluate the diagnostic capacity of Pharmacia CAP System RAST FEIA amoxicilloyl c6 (AXO) and benzylpenicilloyl c1 (BPO) in patients with a documented IgE-mediated penicillin allergy. We studied 129 patients in five groups. Groups 1, 2, and 3 had developed an immediate reaction after penicillin treatment. Group 1 (n=19) were skin test positive to amoxicillin (AX) and/or BPO and/or minor determinant mixture (MDM); group 2 (n=29) were skin test positive to AX but negative to BPO and MDM; and group 3 (n=26) were skin test negative to all determinants, the diagnosis being confirmed by a previous repetitive history or controlled administration. Two control groups, one with nonimmediate reactions -- group 4 (n=25) -- and one with good tolerance to penicillin -- group 5 (n=30) -- were included. All samples were analyzed in vitro for AXO and BPO, and the results compared to the in vivo diagnosis. AX was the drug most often involved. In group 1, 53% were in vitro positive for AXO and 68% for BPO, but 74% had at least one positive test result. In group 2, only 10% had a positive in vitro test to BPO compared to 41% to AXO. In group 3, 42% had positive BPO and/or AXO in vitro tests. In the control groups 4 and 5, the negative in vitro results for AXO were 96% and 100%, and for BPO 100% and 97%, respectively. A positive correlation between specific IgE levels and the time interval from the reaction to the evaluation was found only for group 3. This in vitro assay is beneficial for evaluating subjects allergic to beta-lactams. It is necessary to test for specific IgE to AXO in addition to BPO in patients with immediate allergic reactions after AX. The combination of in vivo and in vitro tests for estimating IgE antibodies to penicillins is important because of the existence of patients with a positive history but negative skin test.

Efficacy of adjuvant chemotherapy for non-small cell lung cancer assessed by metastatic potential associated with ACTN4

PubMed Central

Miura, Nami; Kamita, Masahiro; Kakuya, Takanori; Fujiwara, Yutaka; Tsuta, Koji; Shiraishi, Hideaki; Takeshita, Fumitaka; Ochiya, Takahiro; Shoji, Hirokazu; Huang, Wilber; Ohe, Yuichiro; Yamada, Tesshi; Honda, Kazufumi

2016-01-01

Although several clinical trials have demonstrated the benefits of platinum-combined adjuvant chemotherapy for resected non-small cell lung cancer (NSCLC), predictive biomarkers for the efficacy of such therapy have not yet been identified. Selection of patients with high metastatic ability in the early stage of non-small cell lung cancer (NSCLC) has the potential to predict clinical benefit of adjuvant chemotherapy (ADJ). In order to develop a predictive biomarker for efficacy of ADJ, we reanalyzed patient data using a public database enrolled by JBR.10, which was a clinical trial to probe the clinical benefits of ADJ in stage-IB/II patients with NSCLC. The patients who were enrolled by JBR.10 were classified into 2 subgroups according to expression of the ACTN4 transcript: ACTN4 positive (ACTN4 (+)) and ACTN4 negative (ACTN4 (−)). In the ACTN4 (+) group, overall survival (OS) was significantly higher in the ADJ subgroup compared with the observation subgroup (OBS), indicating a significant survival benefit of ADJ. However, no difference in OS was found between ADJ and OBS groups in ACTN4 (−). Although ACTN4 expression level did not correlate with the chemosensitivity of cancer cell lines for cytotoxic drugs, the metastatic potential of A549 lung adenocarcinoma cells was significantly reduced by ACTN4 shRNA in in vitro assays and in an animal transplantation model. The clinical and preclinical data suggested that ACTN4 is a potential predictive biomarker for efficacy of ADJ in stage-IB/II patients with NSCLC, by reflecting the metastatic potential of tumor cells. PMID:27121206

Surface-Modification of Carbonate Apatite Nanoparticles Enhances Delivery and Cytotoxicity of Gemcitabine and Anastrozole in Breast Cancer Cells

PubMed Central

Mozar, Fitya Syarifa; Chowdhury, Ezharul Hoque

2017-01-01

pH sensitive nanoparticles of carbonate apatite (CA) have been proven to be effective delivery vehicles for DNA, siRNAs and proteins. More recently, conventional anti-cancer drugs, such as doxorubicin, methotrexate and cyclophosphamide have been successfully incorporated into CA for intracellular delivery to breast cancer cells. However, physical and chemical properties of drug molecules appeared to affect their interactions with CA, with hydrophillic drug so far exhibiting better binding affinity and cellular uptakes compared to hydrophobic drugs. In this study, anastrozole, a non-steroidal aromatase inhibitor which is largely hydrophobic, and gemcitabine, a hydrophilic nucleoside inhibitor were used as solubility models of chemotherapy drug. Aggregation tendency of poorly soluble drugs resulting in larger particle-drug complex size might be the main factor hindering their delivery effectiveness. For the first time, surface modification of CA with poly(ethylene glycol) (PEG) has shown promising result to drastically reduce anastrozole- loaded CA particle size, from approximately 1000 to 500 nm based on zeta sizer analysis. Besides PEG, a cell specific ligand, in this case fibronectin, was attached to the particles in order to facilitate receptor mediated endocytosis based on fibronectin–integrin interaction. High-performance liquid chromatography (HPLC) was performed to measure uptake of the drugs by breast cancer cells, revealing that surface modification increased the drug uptake, especially for the hydrophobic drug, compared to the uncoated particles and the free drug. In vitro chemosensitivity assay and in vivo tumor regression study also showed that coated apatite/drug nanoparticle complexes presented higher cytotoxicity and tumor regression effects than uncoated apatite/drug nanoparticles and free drugs, indicating that surface modification successfully created optimum particles size with the consequence of more effective uptake along with favorable pharmacokinetics of the particles. PMID:28590445

Structure/activity relationships for the enhancement by electron-affinic drugs of the anti-tumour effect of CCNU.

PubMed Central

Workman, P.; Twentyman, P. R.

1982-01-01

Using a regrowth-delay assay, we investigated structure/activity relationships for the enhancement by electron-affinic agents of the anti-tumour effect of the nitrosourea CCNU against the KHT sarcoma in C3H mice. A series of neutral 2-nitroimidazoles similar in electron affinity but varying in octanol/water partition coefficient (PC) over 4 orders of magnitude (0.016- greater than 200, Misonidazole = 0.43) were examined at a fixed dose of 2.5 mmol/kg. A parabolic (quadratic) dependence of activity on log PC was observed. Analogues more hydrophilic than misonidazole (MISO) were inactive as were those with very high PCs (greater than 20). Those with PC 0.43--20 were usually more active than MISO, some considerably so. The fairly lipophilic 5-nitroimidazoles nimorazole and metronidazole (METRO) had similar activity to MISO, despite their reduced electron affinity. Two basic 2-nitroimidazoles more efficient as radiosensitizers in vitro likewise showed activity comparable to MISO. We also investigated several agents more electron-affinic than MISO, including some non-nitro compounds. Most were inactive at maximum tolerated doses, but nitrofurazone showed reasonable activity. Sensitizer dose-response curves were obtained for MISO, METRO and two of the most effective agents, benznidazole (Ro 07-1051) and Ro 07-1902. The two latter agents were both considerably more active than MISO at low doses (0.1--0.9 mmol/kg). These studies indicate that the structural features of electron-affinic agents responsible for the enhancement of KHT tumour response to CCNU, are quite different from those affecting radiosensitization, lipophilicity being particularly important. The microsomal enzyme-inhibitor SKF 525A increased the anti-tumour effect of CCNU, suggesting inhibition of CCNU metabolism as one possible mechanism contributing to chemosensitization by lipophilic electron-affinic agents in mice. PMID:7150475

Feasibility and toxicity of concomitant radio/immunotherapy with MabThera (Rituximab®) for patients with non-Hodkin's Lymphoma: results of a prospective phase I/II study.

PubMed

Haidenberger, Alfred; Fromm-Haidenberger, Sabine; de Vries, Alexander; Popper, Bela-Andre; Steurer, Michael; Skvortsova, Ira; Kantner, Johanna; Gunsilius, Eberhard; Lukas, Peter

2011-05-01

Non-Hodgkin's lymphomas (NHL) have a high radio- and chemosensitivity. Although initially responsive, approximately 50% of low grade B-cell lymphomas relapse after 10-15 years. Besides chemo- and radiotherapy, rituximab, a mouse/human chimeric antibody targeting CD20 antigen on the surface of B-cell lymphoma cells, is another treatment approach. In vitro data showed potentiation of radiation-induced apoptosis by addition of rituximab. The purpose of this study was to evaluate the feasibility and toxicity of radiotherapy with concomitant application of rituximab in NHL patients. A total of 21 patients with B-cell lymphoma (stage I: n = 11; II: n = 5; III: n = 1; IV: n = 4) were included in this study, treated with radiotherapy of 30-40 Gy and weekly application of rituximab (375 mg/m²). Nine patients had R-CHOP chemotherapy previously, 1 patient leuceran chemotherapy, and 2 patients an initial treatment with 6 cycles of rituximab. Mean time of follow-up was 41.7 months. No grade 4 toxicity or treatment-related death was observed. In 1 patient, rituximab application had to be stopped after 3 cycles due to radiation-induced side effects. No late toxicities were reported. All patients were in complete remission after treatment. Progression or relapse was observed in 6 patients (28%); the mean time to progression was 27 months. The mean overall survival (OS) was 53 months. Combined radio/immunotherapy is feasible and safe. Treatment was well tolerated, no late toxicities were observed, and treatment outcome is promising. Randomized trials are necessary to clarify the benefit of this treatment approach and its applicability.

Antiangiogenic and Antitumor Effects of Src Inhibition in Ovarian Carcinoma

PubMed Central

Han, Liz Y.; Landen, Charles N.; Trevino, Jose G.; Halder, Jyotsnabaran; Lin, Yvonne G.; Kamat, Aparna A.; Kim, Tae-Jin; Merritt, William M.; Coleman, Robert L.; Gershenson, David M.; Shakespeare, William C.; Wang, Yihan; Sundaramoorth, Raji; Metcalf, Chester A.; Dalgarno, David C.; Sawyer, Tomi K.; Gallick, Gary E.; Sood, Anil K.

2011-01-01

Src, a nonreceptor tyrosine kinase, is a key mediator for multiple signaling pathways that regulate critical cellular functions and is often aberrantly activated in a number of solid tumors, including ovarian carcinoma. The purpose of this study was to determine the role of activated Src inhibition on tumor growth in an orthotopic murine model of ovarian carcinoma. In vitro studies on HeyA8 and SKOV3ip1 cell lines revealed that Src inhibition by the Src-selective inhibitor, AP23846, occurred within 1 hour and responded in a dose-dependent manner. Furthermore, Src inhibition enhanced the cytotoxicity of docetaxel in both chemosensitive and chemoresistant ovarian cancer cell lines, HeyA8 and HeyA8-MDR, respectively. In vivo, Src inhibition by AP23994, an orally bioavailable analogue of AP23846, significantly decreased tumor burden in HeyA8 (P = 0.02), SKOV3ip1 (P = 0.01), as well as HeyA8-MDR (P < 0.03) relative to the untreated controls. However, the greatest effect on tumor reduction was observed in combination therapy with docetaxel (P < 0.001, P = 0.002, and P = 0.01, for the above models, respectively). Proliferating cell nuclear antigen staining showed that Src inhibition alone (P = 0.02) and in combination with docetaxel (P = 0.007) significantly reduced tumor proliferation. In addition, Src inhibition alone and in combination with docetaxel significantly down-regulated tumoral production of vascular endothelial growth factor and interleukin 8, whereas combination therapy decreased the microvessel density (P = 0.02) and significantly affected vascular permeability (P < 0.05). In summary, Src inhibition with AP23994 has potent antiangiogenic effects and significantly reduces tumor burden in preclinical ovarian cancer models. Thus, Src inhibition may be an attractive therapeutic approach for patients with ovarian carcinoma. PMID:16951177

Fructose-bisphosphate aldolase A is a key regulator of hypoxic adaptation in colorectal cancer cells and involved in treatment resistance and poor prognosis.

PubMed

Kawai, Kenji; Uemura, Mamoru; Munakata, Koji; Takahashi, Hidekazu; Haraguchi, Naotsugu; Nishimura, Junichi; Hata, Taishi; Matsuda, Chu; Ikenaga, Masakazu; Murata, Kohei; Mizushima, Tsunekazu; Yamamoto, Hirofumi; Doki, Yuichiro; Mori, Masaki

2017-02-01

Hypoxia is an essential feature of cancer malignancy, but there are no methods for the routine detection of hypoxia-inducible prognostic factors and potential therapeutic targets. We reported previously that the hypoxic tumor cells of metastatic liver tissue from patients with colorectal cancer (CRC) could be used as an 'in vivo' hypoxia culture model. Several potential hypoxia-inducible genes were identified using this model. Among them, one glycolytic enzyme was of special interest. There is currently increasing attention on glycolytic enzymes as potential therapeutic targets due to their association with cancer-specific metabolism. To better understand the molecular mechanisms of cancer malignancy, we investigated the expression of fructose-bisphosphate aldolase A (ALDOA) and its relationship with cancer metabolism. We found that ALDOA was induced by hypoxia in CRC-derived cell lines, and univariate and multivariate analyses of microarray data from the resected CRC samples of 222 patients revealed that ALDOA was an independent prognostic factor for CRC. We also analyzed the malignant potential of ALDOA in vitro using overexpression and knockdown assays. We found that ALDOA was negatively related to chemosensitivity and radiosensitivity and positively associated with proliferation, sphere formation and invasion in both normoxia and hypoxia. These associations were due to the roles of ALDOA in regulating glycolysis, the epithelial-mesenchymal transition and the cell cycle. These findings demonstrate that ALDOA is a hypoxia-inducible prognostic factor that is closely related to CRC malignancy, and also provide new insights into the importance of ALDOA and glycolysis in cancer and suggest new targets for anticancer therapies.

CD133 antisense suppresses cancer cell growth and increases sensitivity to cisplatin in vitro

PubMed Central

BLANCAS-MOSQUEDA, MARISOL; ZAPATA-BENAVIDES, PABLO; ZAMORA-ÁVILA, DIANA; SAAVEDRA-ALONSO, SANTIAGO; MANILLA-MUÑOZ, EDGAR; FRANCO-MOLINA, MOISÉS; DE LA PEÑA, CARMEN MONDRAGÓN; RODRÍGUEZ-PADILLA, CRISTINA

2012-01-01

The increased incidence of cancer in recent years is associated with a high rate of mortality. Numerous types of cancer have a low percentage of CD133+ cells, which have similar features to stem cells. The CD133 molecule is involved in apoptosis and cell proliferation. The aim of this study was to determine the biological effect of CD133 suppression and its role in the chemosensitization of cancer cell lines. RT-PCR and immunocytochemical analyses indicated that CD133 was expressed in the cancer cell lines B16F10, MCF7 and INER51. Downregulation of CD133 by transfection with an antisense sequence (As-CD133) resulted in a decrease in cancer cell viability of up to 52, 47 and 22% in B16F10, MCF-7 and INER51 cancer cell lines, respectively. This decreased viability appeared to be due to the induction of apoptosis. In addition, treatment with As-CD133 in combination with cisplatin had a synergic effect in all of the cancer cell lines analyzed, and in particular, significantly decreased the viability of B16F10 cancer cells compared with each treatment separately (3.1% viability for the combined treatment compared with 48% for 0.4 μg As-CD133 and 25% for 5 ng/μl cisplatin; P<0.05). The results indicate that the downregulation of CD133 by antisense is a potential therapeutic target for cancer and has a synergistic effect when administered with minimal doses of the chemotherapeutic drug cisplatin, suggesting that this combination strategy may be applied in cancer treatment. PMID:23226746

Medullary 5-HT neurons: Switch from tonic respiratory drive to chemoreception during postnatal development

PubMed Central

Cerpa, Veronica J.; Wu, Yuanming; Bravo, Eduardo; Teran, Frida A.; Flynn, Rachel S.; Richerson, George B.

2016-01-01

Serotonin (5-HT) neurons contribute to respiratory chemoreception in adult mice, but it is unclear whether they play a similar role in neonatal mice. We studied breathing during development in Lmx1bf/f/p mice, which lack 5-HT neurons. From postnatal days 1–7 (P1–P7), ventilation of Lmx1bf/f/p mice breathing room air was 50% of WT mice (p < 0.001). By P12, baseline ventilation increased to a level equal to WT mice. In contrast, the hypercapnic ventilatory response (HCVR) of neonatal Lmx1bf/f/p and WT mice were equal to each other, but were both much less than adult WT mice. By P21 the HCVR of WT mice increased to near adult levels, but the HCVR of Lmx1bf/f/p mice had not changed, and was 42% less than WT mice. Primary cell cultures were prepared from the ventromedial medulla of neonatal mice, and patch-clamp recordings were made from neurons identified as serotonergic by expression of a reporter gene. In parallel with developmental changes of the HCVR in vivo, 5-HT neurons had little chemosensitivity to acidosis until 12 days in vitro (DIV), after which their response increased to reach a plateau around 25 DIV. Neonatal Lmx1bf/f/p mice displayed high mortality and decreased growth rate, and this worsened in hypoxia. Mortality was decreased in hyperoxia. These results indicate that maturation of 5-HT neurons contributes to development of respiratory CO2/pH chemoreception during the first few weeks of life in mice in vivo. A defect in the 5-HT system in early postnatal life decreases survival due in part to hypoxia. PMID:27619736

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

PubMed

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

2017-05-01

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

MiR-34a Chemo-Sensitizes Bladder Cancer Cells To Cisplatin Treatment Regardless Of P53-Rb Pathway Status

PubMed Central

Vinall, R.L.; ZRipoll, A.; Wang, S.; Pan, C-X.; White, R.W. deVere

2015-01-01

MiR-34a is a downstream effector of p53 that has been shown to target several molecules associated with cell cycle and cell survival pathways. As alterations in these pathways are frequent in muscle invasive transitional cell carcinoma of the bladder (MI-TCC), for example mutation or loss of p53 and Rb, the goal of this study was to determine whether manipulation of miR-34a expression levels could abrogate the effect of these alterations and sensitize bladder cancer cells to chemotherapy. We demonstrate that transfection of T24, TCCSUP and 5637 with pre-miR-34a followed by cisplatin treatment results in a dramatic reduction in clonogenic potential and induction of senescence compared to treatment with cisplatin alone. Molecular analyses identified Cdk6 and SIRT-1 as being targeted by miR-34a in MI-TCC cells, however, inhibition of Cdk6 and SIRT-1 was not as effective as pre-miR-34a in mediating chemosensitization. Analysis of 27 pre-neoadjuvant chemotherapy patient samples revealed many of the patients who subsequently did not respond to treatment (based on surgical resection post-chemotherapy and 5 year survival data) express lower levels of miR-34a, however, a statistically significant difference between the responder and non-responder groups was not observed (p=0.1174). Analysis of 8 sets of pre- and post-neoadjuvant chemotherapy patient samples determined miR-34a expression increased post-chemotherapy in only 2 of the 8 patients. The combined data indicate that elevation of miR-34a expression levels prior to chemotherapy would be of benefit to MI-TCC patients, particularly in a setting of low miR-34a expression. PMID:21702042

Acquisition of Relative Interstrand Crosslinker Resistance and PARP Inhibitor Sensitivity in Fanconi Anemia Head and Neck Cancers.

PubMed

Lombardi, Anne J; Hoskins, Elizabeth E; Foglesong, Grant D; Wikenheiser-Brokamp, Kathryn A; Wiesmüller, Lisa; Hanenberg, Helmut; Andreassen, Paul R; Jacobs, Allison J; Olson, Susan B; Keeble, Winifred W; Hays, Laura E; Wells, Susanne I

2015-04-15

Fanconi anemia is an inherited disorder associated with a constitutional defect in the Fanconi anemia DNA repair machinery that is essential for resolution of DNA interstrand crosslinks. Individuals with Fanconi anemia are predisposed to formation of head and neck squamous cell carcinomas (HNSCC) at a young age. Prognosis is poor, partly due to patient intolerance of chemotherapy and radiation requiring dose reduction, which may lead to early recurrence of disease. Using HNSCC cell lines derived from the tumors of patients with Fanconi anemia, and murine HNSCC cell lines derived from the tumors of wild-type and Fancc(-/-) mice, we sought to define Fanconi anemia-dependent chemosensitivity and DNA repair characteristics. We utilized DNA repair reporter assays to explore the preference of Fanconi anemia HNSCC cells for non-homologous end joining (NHEJ). Surprisingly, interstrand crosslinker (ICL) sensitivity was not necessarily Fanconi anemia-dependent in human or murine cell systems. Our results suggest that the increased Ku-dependent NHEJ that is expected in Fanconi anemia cells did not mediate relative ICL resistance. ICL exposure resulted in increased DNA damage sensing and repair by PARP in Fanconi anemia-deficient cells. Moreover, human and murine Fanconi anemia HNSCC cells were sensitive to PARP inhibition, and sensitivity of human cells was attenuated by Fanconi anemia gene complementation. The observed reliance upon PARP-mediated mechanisms reveals a means by which Fanconi anemia HNSCCs can acquire relative resistance to the ICL-based chemotherapy that is a foundation of HNSCC treatment, as well as a potential target for overcoming chemoresistance in the chemosensitive individual. ©2015 American Association for Cancer Research.

High content screening of patient-derived cell lines highlights the potential of non-standard chemotherapeutic agents for the treatment of glioblastoma.

PubMed

Yu, Kenny Kwok-Hei; Taylor, Jessica T; Pathmanaban, Omar N; Youshani, Amir Saam; Beyit, Deniz; Dutko-Gwozdz, Joanna; Benson, Roderick; Griffiths, Gareth; Peers, Ian; Cueppens, Peter; Telfer, Brian A; Williams, Kaye J; McBain, Catherine; Kamaly-Asl, Ian D; Bigger, Brian W

2018-01-01

Glioblastoma (GBM) is the most common primary brain malignancy in adults, yet survival outcomes remain poor. First line treatment is well established, however disease invariably recurs and improving prognosis is challenging. With the aim of personalizing therapy at recurrence, we have established a high content screening (HCS) platform to analyze the sensitivity profile of seven patient-derived cancer stem cell lines to 83 FDA-approved chemotherapy drugs, with and without irradiation. Seven cancer stem cell lines were derived from patients with GBM and, along with the established cell line U87-MG, each patient-derived line was cultured in tandem in serum-free conditions as adherent monolayers and three-dimensional neurospheres. Chemotherapeutics were screened at multiple concentrations and cells double-stained to observe their effect on both cell death and proliferation. Sensitivity was classified using high-throughput algorithmic image analysis. Cell line specific drug responses were observed across the seven patient-derived cell lines. Few agents were seen to have radio-sensitizing effects, yet some drug classes showed a marked difference in efficacy between monolayers and neurospheres. In vivo validation of six drugs suggested that cell death readout in a three-dimensional culture scenario is a more physiologically relevant screening model and could be used effectively to assess the chemosensitivity of patient-derived GBM lines. The study puts forward a number of non-standard chemotherapeutics that could be useful in the treatment of recurrent GBM, namely mitoxantrone, bortezomib and actinomycin D, whilst demonstrating the potential of HCS to be used for personalized treatment based on the chemosensitivity profile of patient tumor cells.

Curcumin Enhances the Efficacy of Chemotherapy by Tailoring p65NFκB-p300 Cross-talk in Favor of p53-p300 in Breast Cancer*

PubMed Central

Sen, Gouri Sankar; Mohanty, Suchismita; Hossain, Dewan Md Sakib; Bhattacharyya, Sankar; Banerjee, Shuvomoy; Chakraborty, Juni; Saha, Shilpi; Ray, Pallab; Bhattacharjee, Pushpak; Mandal, Debaprasad; Bhattacharya, Arindam; Chattopadhyay, Samit; Das, Tanya; Sa, Gaurisankar

2011-01-01

Breast cancer cells often develop multiple mechanisms of drug resistance during tumor progression, which is the major reason for the failure of breast cancer therapy. High constitutive activation of NFκB has been found in different cancers, creating an environment conducive for chemotherapeutic resistance. Here we report that doxorubicin-induced SMAR1-dependent transcriptional repression and SMAR1-independent degradation of IkBα resulted in nuclear translocation of p65NFκB and its association with p300 histone acetylase and subsequent transcription of Bcl-2 to impart protective response in drug-resistant cells. Consistently SMAR1-silenced drug-resistant cells exhibited IkBα-mediated inhibition of p65NFκB and induction of p53-dependent apoptosis. Interestingly, curcumin pretreatment of drug-resistant cells alleviated SMAR1-mediated p65NFκB activation and hence restored doxorubicin sensitivity. Under such anti-survival condition, induction of p53-p300 cross-talk enhanced the transcriptional activity of p53 and intrinsic death cascade. Importantly, promyelocyte leukemia-mediated SMAR1 sequestration that relieved the repression of apoptosis-inducing genes was indispensable for such chemo-sensitizing ability of curcumin. A simultaneous decrease in drug-induced systemic toxicity by curcumin might also have enhanced the efficacy of doxorubicin by improving the intrinsic defense machineries of the tumor-bearer. Overall, the findings of this preclinical study clearly demonstrate the effectiveness of curcumin to combat doxorubicin-resistance. We, therefore, suggest curcumin as a potent chemo-sensitizer to improve the therapeutic index of this widely used anti-cancer drug. Taken together, these results suggest that curcumin can be developed into an adjuvant chemotherapeutic drug. PMID:22013068

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

Kumar, Ajay; Kant, Shiva; Singh, Sukh Mahendra, E-mail: sukhmahendrasingh@yahoo.com

Targeting of tumor metabolism is emerging as a novel therapeutic strategy against cancer. Dichloroacetate (DCA), an inhibitor of pyruvate dehydrogenase kinase (PDK), has been shown to exert a potent tumoricidal action against a variety of tumor cells. The main mode of its antineoplastic action implicates a shift of glycolysis to oxidative metabolism of glucose, leading to generation of cytotoxic reactive oxygen intermediates. However, the effect of DCA on tumor microenvironment, which in turn regulates tumor cell survival; remains speculative to a large extent. It is also unclear if DCA can exert any modulatory effect on the process of hematopoiesis, whichmore » is in a compromised state in tumor-bearing hosts undergoing chemotherapy. In view of these lacunas, the present study was undertaken to investigate the so far unexplored aspects with respect to the molecular mechanisms of DCA-dependent tumor growth retardation and chemosensitization. BALB/c mice were transplanted with Dalton's lymphoma (DL) cells, a T cell lymphoma of spontaneous origin, followed by administration of DCA with or without cisplatin. DCA-dependent tumor regression and chemosensitization to cisplatin was found to be associated with altered repertoire of key cell survival regulatory molecules, modulated glucose metabolism, accompanying reconstituted tumor microenvironment with respect to pH homeostasis, cytokine balance and alternatively activated TAM. Moreover, DCA administration also led to an alteration in the MDR phenotype of tumor cells and myelopoietic differentiation of macrophages. The findings of this study shed a new light with respect to some of the novel mechanisms underlying the antitumor action of DCA and thus may have immense clinical applications. - Highlights: • DCA modulates tumor progression and chemoresistance. • DCA alters molecules regulating cell survival, glucose metabolism and MDR. • DCA reconstitutes biophysical and cellular composition of tumor microenvironment. • DCA augments BMC cellularity, differentiation and repolarization of macrophages.« less

Chaetominine reduces MRP1-mediated drug resistance via inhibiting PI3K/Akt/Nrf2 signaling pathway in K562/Adr human leukemia cells

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

Yao, Jingyun; Wei, Xing; Shanghai Collaborative Innovation Center for Biomanufacturing Technology, 130 Meilong Road, Shanghai

Drug resistance limits leukemia treatment and chaetominine, a cytotoxic alkaloid that promotes apoptosis in a K562 human leukemia cell line via the mitochondrial pathway was studied with respect to chemoresistance in a K562/Adr human resistant leukemia cell line. Cytotoxicity assays indicated that K562/Adr resistance to adriamycin (ADR) did not occur in the presence of chaetominine and that chaetominine increased chemosensitivity of K562/Adr to ADR. Data show that chaetominine enhanced ADR-induced apoptosis and intracellular ADR accumulation in K562/Adr cells. Accordingly, chaetominine induced apoptosis by upregulating ROS, pro-apoptotic Bax and downregulating anti-apoptotic Bcl-2. RT-PCR and western-blot confirmed that chaetominine suppressed highly expressedmore » MRP1 at mRNA and protein levels. But little obvious alternation of another drug transporter MDR1 mRNA was observed. Furthermore, inhibition of MRP1 by chaetominine relied on inhibiting Akt phosphorylation and nuclear Nrf2. In summary, chaetominine strongly reverses drug resistance by interfering with the PI3K/Akt/Nrf2 signaling, resulting in reduction of MRP1-mediated drug efflux and induction of Bax/Bcl-2-dependent apoptosis in an ADR-resistant K562/Adr leukemia cell line. - Highlights: • Chaetominine enhanced chemosensitivity of ADR against K562/Adr cells. • Chaetominine increased intracellular ADR levels via inhibiting MRP1. • Chaetominine induced apoptosis of K562/Adr cells through upregulation of ROS and modulation of Bax/Bcl-2. • Inhibition of MRP1 and Nrf2 by chaetominine treatment was correlative with blockade of PI3K/Akt signaling.« less

Bypassing multidrug resistant ovarian cancer using ultrasound responsive doxorubicin/curcumin co-deliver alginate nanodroplets.

PubMed

Baghbani, Fatemeh; Moztarzadeh, Fathollah

2017-05-01

Ultrasound-responsive perfluorocarbon nanoemulsions are a class of new multifunctional smart nanocarriers which combine diagnostic properties with therapeutic properties and release their drug payload in a controlled manner in response to ultrasound. Therefore, combination therapy using chemotherapeutic and chemosensitizing agents co-entrapped in these nanocarriers seems beneficial for cancer treatment. In the present study, multifunctional smart alginate/perfluorohexane nanodroplets were developed for co-delivery of doxorubicin and curcumin (a strong chemosensitizer). The nanodroplets with the average particle size of 55.1nm were synthesized via nanoemulsion process. The entrapment efficiency of doxorubicin was 92.3%. To improve curcumin entrapment into the alginate shell, Span 60 was added to the formulation as a co-surfactant and finally curcumin entrapment of about 40% was achieved. Ultrasound-mediated drug release kinetic was evaluated at two different frequencies of 28kHz (low frequency) and 1MHz (high frequency). Low frequency ultrasound resulted in higher triggered drug release from nanodroplets. The nanodroplets showed strong ultrasound contrast via droplet to bubble transition as confirmed via B-mode ultrasound imaging. Enhanced cytotoxicity in adriamycin-resistant A2780 ovarian cancer cells was observed for Dox-Cur-NDs compared to Dox-NDs because of the synergistic effects of doxorubicin and curcumin. However, ultrasound irradiation significantly increased the cytotoxicity of Dox-Cur-NDs. Finally, in vivo ovarian cancer treatment using Dox/Cur-NDs combined with ultrasound irradiation resulted in efficient tumor regression. According to the present study, nanotherapy of multidrug resistant human ovarian cancer using ultrasound responsive doxorubicin/curcumin co-loaded alginate-shelled nanodroplets combined with ultrasound irradiation could be a promising modality for the future of cancer treatment. Copyright © 2017 Elsevier B.V. All rights reserved.

Genetically heterogeneous glioblastoma recurring with disappearance of 1p/19q losses: case report.

PubMed

Ito, Motokazu; Wakabayashi, Toshihiko; Natsume, Atsushi; Hatano, Hisashi; Fujii, Masazumi; Yoshida, Jun

2007-07-01

Intratumor heterogeneity is of great importance in many clinical aspects of glioma biology, including tumor grading, therapeutic response, and recurrence. Modifications in the genetic features of a specific primary tumor recurring after chemo- and radiotherapy are poorly understood. We report a recurrent glioblastoma case exhibiting loss of heterozygosity (LOH) on chromosome 10q, while the primary tumor exhibited heterogeneity in the LOH status of 1p, 19q, and 10q. To determine the relationship between such modifications and heterogeneous chemosensitivity, primary cultured cells heterogeneously showing 1p/19q/10q losses were established from a surgical specimen of oligoastrocytoma and were treated with chemotherapeutic agents. A 46-year-old woman with a 1-month history of headache and visual disturbances presented to our institution. A right temporoparietal craniotomy and gross total resection were performed. The pathological diagnosis was glioblastoma multiforme with oligodendroglial components. Whereas LOH on 10q was identified at all tumor sites, only the oligodendroglial components exhibited LOH on 1p and 19q. The tumor recurred 6 months after postoperative chemotherapy using interferon-beta and ranimustine, as well as a course of fractionated external-beam radiotherapy (total dose, 60 Gy). Gene analysis revealed no 1p/19q allelic losses but only 10q LOH. Intratumor heterogeneity might be explained by the presence of more than one subclone in the primary tumor. Here, the tumor cells exhibiting 1p/19q LOH with high chemosensitivity might have been killed by the adjuvant therapy and those exhibiting 10q LOH with chemoresistance recurred. This study and our preliminary laboratory findings might suggest an approach to brain tumor physiology, diagnosis, and therapy.

Post-autologous transplant maintenance therapies in lymphoid malignancies: are we there yet?

PubMed

Epperla, N; Fenske, T S; Lazarus, H M; Hamadani, M

2015-11-01

Disease relapse after autologous hematopoietic transplant (auto-HCT) remains the number one cause of post-transplant therapy failure and mortality. The last decade has seen a proliferation of clinical studies looking at the prevention of post-auto-HCT therapy failure with various maintenance strategies. The benefit of such therapies is in turn dependent on disease histology and timing of transplantation. Although high dose therapy (HDT) provides durable responses in chemosensitive relapsed diffuse large B-cell lymphoma (DLBCL), a sizable subset experiences disease relapse. Unfortunately, the addition of rituximab as a post-auto-HCT maintenance strategy did not improve survival outcomes. The preliminary results with programmed death -1 (PD-1) Ab as post-auto maintenance in DLBCL is promising but requires randomized validation. In follicular lymphoma, the 5- and 10-year PFS rates are ~60% and 31%, respectively. Although the addition of rituximab improved PFS, there is no survival benefit, to date. Disease relapse after auto-HCT in mantle cell lymphoma (MCL) is not uncommon. Rituximab maintenance in this setting provides a PFS benefit. Given the poor prognosis of post-auto-HCT failures in MCL, maintenance can be considered on a case-by-case basis. In chemosensitive relapsed Hodgkin lymphoma, addition of brentuximab vedotin after auto-HCT improved 2-year PFS (65 vs 45%) and can be considered as an option for maintenance therapy post auto-HCT, in select higher risk patients. Ongoing trials evaluating the efficacy of post-auto-HCT maintenance with novel agents (for example, immunomodulators, proteasome inhibitors, PD-1 inhibitors, Bruton's tyrosine kinase inhibitors and so on) will likely change the practice landscape for lymphoma patients following HDT and auto-HCT.

Nutrition Modulation of Cardiotoxicity and Anticancer Efficacy Related to Doxorubicin Chemotherapy by Glutamine and ω-3 Polyunsaturated Fatty Acids

PubMed Central

Xue, Hongyu; Ren, Wenhua; Denkinger, Melanie; Schlotzer, Ewald; Wischmeyer, Paul E.

2015-01-01

Background Doxorubicin (DOX) has been one of the most effective antitumor agents against a broad spectrum of malignancies. However, DOX-induced cardiotoxicity forms the major cumulative dose-limiting factor. Glutamine and ω-3 polyunsaturated fatty acids (PUFAs) are putatively cardioprotective during various stresses and/or have potential chemosensitizing effects during cancer chemotherapy. Methods Antitumor activity and cardiotoxicity of DOX treatment were evaluated simultaneously in a MatBIII mammary adenocarcinoma tumor-bearing rat model treated with DOX (cumulative dose 12 mg/kg). Single or combined treatment of parenteral glutamine (0.35 g/kg) and ω-3 PUFAs (0.19 g/kg eicosapentaenoic acid and 0.18 g/kg docosahexaenoic acid) was administered every other day, starting 6 days before chemotherapy initiation until the end of study (day 50). Results Glutamine alone significantly prevented DOX-related deterioration of cardiac function, reduced serum cardiac troponin I levels, and diminished cardiac lipid peroxidation while not affecting tumor inhibition kinetics. Single ω-3 PUFA treatment significantly enhanced antitumor activity of DOX associated with intensified tumoral oxidative stress and enhanced tumoral DOX concentration while not potentiating cardiac dysfunction or increasing cardiac oxidative stress. Intriguingly, providing glutamine and ω-3 PUFAs together did not consistently confer a greater benefit; conversely, individual benefits on cardiotoxicity and chemosensitization were mostly attenuated or completely lost when combined. Conclusions Our data demonstrate an interesting differentiality or even dichotomy in the response of tumor and host to single parenteral glutamine and ω-3 PUFA treatments. The intriguing glutamine × ω-3 PUFA interaction observed draws into question the common assumption that there are additive benefits of combinations of nutrients that are beneficial on an individual basis. PMID:25888676

Anti-miR21 oligonucleotide enhances chemosensitivity of T98G cell line to doxorubicin by inducing apoptosis

PubMed Central

Giunti, Laura; da Ros, Martina; Vinci, Serena; Gelmini, Stefania; Iorio, Anna Lisa; Buccoliero, Anna Maria; Cardellicchio, Stefania; Castiglione, Francesca; Genitori, Lorenzo; de Martino, Maurizio; Giglio, Sabrina; Genuardi, Maurizio; Sardi, Iacopo

2015-01-01

Various signal transduction pathways seem to be involved in chemoresistance mechanism of glioblastomas (GBMs). miR-21 is an important oncogenic miRNA which modulates drug resistance of tumor cells. We analyzed the expression of 5 miRNAs, previously found to be dysregulated in high grade gliomas, in 9 pediatric (pGBM) and in 5 adult (aGBM) GBMs. miR-21 was over-expressed, with a significant difference between pGBMs and aGBMs represented by a 4 times lower degree of expression in the pediatric compared to the adult series (p = 0.001). Doxorubicin (Dox) seems to be an effective anti-glioma agent with high antitumor activity also against glioblastoma stem cells. We therefore evaluated the chemosensitivity to Dox in 3 GBM cell lines (A172, U87MG and T98G). Dox had a cytotoxic effect after 48 h of treatment in A172 and U87MG, while T98G cells were resistant. TUNEL assay verified that Dox induced apoptosis in A172 and U87MG but not in T98G. miR-21 showed a low basal expression in treated cells and was over-expressed in untreated cells. To validate the possible association of miR-21 with drug resistance of T98G cells, we transfected anti-miR-21 inhibitor into the cells. The expression level of miR-21 was significantly lower in T98G transfected cells (than in the parental control cells). Transfected cells showed a high apoptotic rate compared to control after Dox treatment by TUNEL assay, suggesting that combined Dox and miR-21 inhibitor therapy can sensitize GBM resistant cells to anthracyclines by enhancing apoptosis. PMID:25628933

Cabazitaxel Versus Topotecan in Patients with Small-Cell Lung Cancer with Progressive Disease During or After First-Line Platinum-Based Chemotherapy.

PubMed

Evans, Tracey L; Cho, Byoung Chul; Udud, Katalin; Fischer, Juergen R; Shepherd, Frances A; Martinez, Pablo; Ramlau, Rodryg; Syrigos, Konstantinos N; Shen, Liji; Chadjaa, Mustapha; Wolf, Martin

2015-08-01

Patients with small-cell lung cancer (SCLC) typically respond well to initial chemotherapy. However, relapse invariably occurs, and topotecan, the only approved second-line treatment option, has limited efficacy. Taxanes have activity in SCLC, and cabazitaxel is a second-generation taxane with potential for enhanced activity in chemorefractory malignancies. Patients with SCLC who relapsed after initial platinum-based chemotherapy were randomly assigned to receive cabazitaxel 25 mg/m every 21 days or topotecan 1.5 mg/m on days 1-5 every 21 days. Two patient subgroups, defined by chemosensitive and chemo-resistant/refractory disease, were assessed in combination and separately. The safety profile of cabazitaxel and topotecan was consistent with previous studies, and despite considerable toxicity in both arms, no new safety concerns were identified. Patients receiving cabazitaxel had inferior progression-free survival compared with topotecan (1.4 versus 3.0 months, respectively; two-sided p < 0.0001; hazard ratio = 2.17, 95% confidence interval = 1.563-3.010), and results were similar in both the chemosensitive and chemorefractory subgroups. No complete responses were observed in either arm, and no partial responses were observed in the cabazitaxel group. The partial response rate in the topotecan arm was 10%. Median overall survival was 5.2 months in the cabazitaxel arm and 6.8 months in the topotecan arm (two-sided p = 0.0125; hazard ratio = 1.57, 95% confidence interval = 1.10-2.25). Cabazitaxel, a next-generation taxane, had inferior efficacy when compared with standard-dose topotecan in the treatment of relapsed SCLC. Topotecan remains a suboptimal therapy, and continued efforts to develop improved second-line treatments are warranted.

Temozolomide downregulates P-glycoprotein expression in glioblastoma stem cells by interfering with the Wnt3a/glycogen synthase-3 kinase/β-catenin pathway

PubMed Central

Riganti, Chiara; Salaroglio, Iris Chiara; Caldera, Valentina; Campia, Ivana; Kopecka, Joanna; Mellai, Marta; Annovazzi, Laura; Bosia, Amalia; Ghigo, Dario; Schiffer, Davide

2013-01-01

Background Glioblastoma multiforme stem cells display a highly chemoresistant phenotype, whose molecular basis is poorly known. We aim to clarify this issue and to investigate the effects of temozolomide on chemoresistant stem cells. Methods A panel of human glioblastoma cultures, grown as stem cells (neurospheres) and adherent cells, was used. Results Neurospheres had a multidrug resistant phenotype compared with adherent cells. Such chemoresistance was overcome by apparently noncytotoxic doses of temozolomide, which chemosensitized glioblastoma cells to doxorubicin, vinblastine, and etoposide. This effect was selective for P-glycoprotein (Pgp) substrates and for stem cells, leading to an investigation of whether there was a correlation between the expression of Pgp and the activity of typical stemness pathways. We found that Wnt3a and ABCB1, which encodes for Pgp, were both highly expressed in glioblastoma stem cells and reduced by temozolomide. Temozolomide-treated cells had increased methylation of the cytosine–phosphate–guanine islands in the Wnt3a gene promoter, decreased expression of Wnt3a, disrupted glycogen synthase-3 kinase/β-catenin axis, reduced transcriptional activation of ABCB1, and a lower amount and activity of Pgp. Wnt3a overexpression was sufficient to transform adherent cells into neurospheres and to simultaneously increase proliferation and ABCB1 expression. On the contrary, glioblastoma stem cells silenced for Wnt3a lost the ability to form neurospheres and reduced at the same time the proliferation rate and ABCB1 levels. Conclusions Our work suggests that Wnt3a is an autocrine mediator of stemness, proliferation, and chemoresistance in human glioblastoma and that temozolomide may chemosensitize the stem cell population by downregulating Wnt3a signaling. PMID:23897632

Nutrition Modulation of Cardiotoxicity and Anticancer Efficacy Related to Doxorubicin Chemotherapy by Glutamine and ω-3 Polyunsaturated Fatty Acids.

PubMed

Xue, Hongyu; Ren, Wenhua; Denkinger, Melanie; Schlotzer, Ewald; Wischmeyer, Paul E

2016-01-01

Doxorubicin (DOX) has been one of the most effective antitumor agents against a broad spectrum of malignancies. However, DOX-induced cardiotoxicity forms the major cumulative dose-limiting factor. Glutamine and ω-3 polyunsaturated fatty acids (PUFAs) are putatively cardioprotective during various stresses and/or have potential chemosensitizing effects during cancer chemotherapy. Antitumor activity and cardiotoxicity of DOX treatment were evaluated simultaneously in a MatBIII mammary adenocarcinoma tumor-bearing rat model treated with DOX (cumulative dose 12 mg/kg). Single or combined treatment of parenteral glutamine (0.35 g/kg) and ω-3 PUFAs (0.19 g/kg eicosapentaenoic acid and 0.18 g/kg docosahexaenoic acid) was administered every other day, starting 6 days before chemotherapy initiation until the end of study (day 50). Glutamine alone significantly prevented DOX-related deterioration of cardiac function, reduced serum cardiac troponin I levels, and diminished cardiac lipid peroxidation while not affecting tumor inhibition kinetics. Single ω-3 PUFA treatment significantly enhanced antitumor activity of DOX associated with intensified tumoral oxidative stress and enhanced tumoral DOX concentration while not potentiating cardiac dysfunction or increasing cardiac oxidative stress. Intriguingly, providing glutamine and ω-3 PUFAs together did not consistently confer a greater benefit; conversely, individual benefits on cardiotoxicity and chemosensitization were mostly attenuated or completely lost when combined. Our data demonstrate an interesting differentiality or even dichotomy in the response of tumor and host to single parenteral glutamine and ω-3 PUFA treatments. The intriguing glutamine × ω-3 PUFA interaction observed draws into question the common assumption that there are additive benefits of combinations of nutrients that are beneficial on an individual basis. © 2015 American Society for Parenteral and Enteral Nutrition.

G6PD as a predictive marker for glioma risk, prognosis and chemosensitivity.

PubMed

Yang, Chin-An; Huang, Hsi-Yuan; Lin, Cheng-Li; Chang, Jan-Gowth

2018-05-29

Glucose-6-phosphate dehydrogenase (G6PD) is a key enzyme preventing cells from oxidative damage and has been reported to have tumor-promoting roles. This study aims to comprehensively evaluate the predictive values of G6PD on brain tumor risk, prognosis and chemo-resistance. A retrospective 13-year cohort study analyzing cancer risk using the Taiwan National Health Insurance Research Database (4066 G6PD deficiency patients and 16,264 controls) was conducted. Furthermore, RNAseq and clinical data of grade II-III glioma (LGG, n = 515) and glioblastoma (GBM, n = 155) were downloaded from The Cancer Genome Atlas (TCGA) and analyzed. Bioinformatics methods were applied to build a glioma prognostication model and to predict response to chemotherapy based on tumor G6PD-related gene expressions. The predicted results were validated in another glioma cohort GSE 16011 and in KALS1 cell line. G6PD-dificient patients were found to have an increased risk for cancers, especially for brain tumor (adjusted hazard ratio (HR) 10.5, 95% CI 1.03-7.60). Furthermore, higher tumor G6PD expression was associated with poor patient survival in LGG, but not in GBM. A prognostication model using expression levels of G6PD and 9 related genes (PSMA2, PSMB8, SHFM1, GSS, GSTK1, MGST2, POLD3, MSH2, MSH6) could independently predict LGG patient survival. Boosted decision tree analysis on 213 cancer cell line database revealed predictive values of G6PD expression on response to gemcitabine and bortezomib. Knockdown of G6PD in KALS1 cell line enhanced its sensitivity to both chemotherapeutic agents. Our study suggests that G6PD could be a marker predicting glioma risk, prognosis and chemo-sensitivity.

Chemohypersensitivity and autonomic modulation of venous capacitance in the pathophysiology of acute decompensated heart failure.

PubMed

Burchell, Amy E; Sobotka, Paul A; Hart, Emma C; Nightingale, Angus K; Dunlap, Mark E

2013-06-01

Heart failure is increasing in prevalence around the world, with hospitalization and re-hospitalization as a result of acute decompensated heart failure (ADHF) presenting a huge social and economic burden. The mechanism for this decompensation is not clear. Whilst in some cases it is due to volume expansion, over half of patients with an acute admission for ADHF did not experience an increase in total body weight. This calls into question the current treatment strategy of targeting salt and water retention in ADHF. An alternative hypothesis proposed by Fallick et al. is that an endogenous fluid shift from the splanchnic bed is implicated in ADHF, rather than an exogenous fluid gain. The hypothesis states further that this shift is triggered by an increase in sympathetic tone causing vasoconstriction in the splanchnic bed, a mechanism that can translocate blood rapidly into the effective circulating volume, generating the raised venous pressure and congestion seen in ADHF. This hypothesis encourages a new clinical paradigm which focuses on the underlying mechanisms of congestion, and highlights the importance of fluid redistribution and neurohormonal activation in its pathophysiology. In this article, we consider the concept that ADHF is attributable to episodic sympathetic hyperactivity, resulting in fluid shifts from the splanchnic bed. Chemosensitivity is a pathologic autonomic mechanism associated with mortality in patients with systolic heart failure. Tonic and episodic activity of the peripheral chemoreceptors may underlie the syndrome of acute decompensation without total body salt and water expansion. We suggest in this manuscript that chemosensitivity in response to intermittent hypoxia, such as experienced in sleep disordered breathing, may explain the intermittent sympathetic hyperactivity underlying renal sodium retention and acute volume redistribution from venous storage sites. This hypothesis provides an alternative structure to guide novel diagnostic and treatment strategies for ADHF.

The novel heterocyclic trioxirane [(1,3,5-tris oxiran-2-yl)methyl)-1,3,5-triazinane-2,4,6-trione (TATT)] exhibits a better anticancer effect than platinum-based chemotherapy by induction of apoptosis and curcumin further enhances its chemosensitivity.

PubMed

Su, Chun-Li; Wang, Ying-Ti; Chang, Mu-Hsin; Fang, Kang; Chen, Kwunmin

2014-04-01

The heterocyclic trioxirane compound [1,3,5-tris((oxiran-2-yl)methyl)-1,3,5-triazinane-2,4,6-trione (TATT)] is a synthetic compound which has been used as an experimental anticancer agent in human clinical trials. Curcumin, an active natural compound in turmeric and curry, is an ingredient commonly used in the traditional diet of many Asian countries. In the present study, we observed that TATT exhibited a better anticancer effect on chemoresistant human colorectal cancer HT-29 cells and displayed less cytotoxicity on normal human umbilical vein endothelial cells, compared with FDA-approved anticancer drugs (cisplatin, carboplatin, or oxaliplatin) using MTT assay. TATT also induced a stronger apoptotic effect than that seen with the three studied anticancer drugs, as characterized by externalization of phosphatidylserine using flow cytometry. Administration of caspase 8-specific inhibitor (z-IETD-fmk) and mitochondrial permeability transition pore inhibitor (cyclosporin A) demonstrated that TATT-induced apoptosis proceeded via both extrinsic and intrinsic signaling pathways. It is noteworthy that coadministration of curcumin further significantly increased TATT-induced cytotoxicity, externalization of phosphatidylserine (representing early apoptosis), and the percentages of cells at the sub-G1 phase (representing late apoptosis), producing an additivity and/or synergistic effect, and vice versa. Suppression of nuclear NF-κB was involved in curcumin-enhanced chemosensitivity of TATT. Overall, our data indicate that TATT exerts a chemotherapeutic effect on colorectal cancer cells and coadministration of curcumin enhances the treatment effect of TATT.

Characterization of LHY-821, a novel moderately differentiated endometrial carcinoma cell line.

PubMed

Hu, Qian; Yu, Li; Chen, Rui; Zhang, Yan; Xie, Ya; Liao, Qinping

2012-08-01

Endometrial cancer is a major problem for women but only a small number of comprehensively characterized cell models are available for studies. Here, we established a new cell line derived from a Stage IIIc(1) Grade 2 endometrial adenocarcinoma. The cell line, designated LHY-821, was characterized using growth curve, karyotyping, immunohistochemical staining, immunoblotting, drug sensitivity assay, invasion assay, and xenografting in nude mice. LHY-821 has a doubling time of about 46 h and a colony-forming efficiency of approximately 71 %. These cells expresse high levels of progesterone receptor but not estrogen receptor and are sensitive to medroxyprogesterone acetate (MPA). LHY-821 also expresses pan-cytokeratin, PTEN, p53, β-catenin, IGF-1, and IGF-2. In addition, karyotype analysis revealed that LHY-821 possessed a near diploid karyotype including 6q-, 10p-, Xq-, 13q+, 17p+, and Triplo-12. LHY-821 showed highly tumorigenicity in nude mice (100 %) and weak invasiveness. Chemosensitivity tests showed that LHY-821 was sensitive to both carboplatin and paclitaxel. LHY-821 is an immortalized cell line which had survived more than 80 serial passages; it may provide a novel tool to study the molecular mechanism and potential treatment for endometrial cancer.

A composite sensor array impedentiometric electronic tongue Part II. Discrimination of basic tastes.

PubMed

Pioggia, G; Di Francesco, F; Marchetti, A; Ferro, M; Leardi, R; Ahluwalia, A

2007-05-15

An impedentiometric electronic tongue based on the combination of a composite sensor array and chemometric techniques aimed at the discrimination of soluble compounds able to elicit different gustative perceptions is presented. A composite array consisting of chemo-sensitive layers based on carbon nanotubes or carbon black dispersed in polymeric matrices and doped polythiophenes was used. The electrical impedance of the sensor array was measured at a frequency of 150 Hz by means of an impedance meter. The experimental set-up was designed in order to allow the automatic selection of a test solution and dipping of the sensor array following a dedicated measurement protocol. Measurements were carried out on 15 different solutions eliciting 5 different tastes (sodium chloride, citric acid, glucose, glutamic acid and sodium dehydrocholate for salty, sour, sweet, umami and bitter, respectively) at 3 concentration levels comprising the human perceptive range. In order to avoid over-fitting, more than 100 repetitions for each sample were carried in a 4-month period. Principal component analysis (PCA) was used to detect and remove outliers. Classification was performed by linear discriminant analysis (LDA). A fairly good degree of discrimination was obtained.

Solitary chemoreceptor cell proliferation in adult nasal epithelium.

PubMed

Gulbransen, Brian D; Finger, Thomas E

2005-03-01

Nasal trigeminal chemosensitivity in mice and rats is mediated in part by solitary chemoreceptor cells (SCCs) in the nasal epithelium (Finger et al., 2003). Many nasal SCCs express the G-protein alpha-gustducin as well as other elements of the bitter-taste signaling cascade including phospholipase Cbeta2, TRPM5 and T2R bitter-taste receptors. While some populations of sensory cells are replaced throughout life (taste and olfaction), others are not (hair cells and carotid body chemoreceptors). These experiments were designed to test whether new SCCs are generated within the epithelium of adult mice. Wild type C57/B6 mice were injected with the thymidine analog 5-bromo-2'-deoxyuridine (BrdU) to label dividing cells. At various times after injection (1-40 days), the mice were perfused with 4% paraformaldehyde and prepared for dual-label immunocytochemistry. Double labeled cells were detected as early as 3 days post BrdU injection and remained for as long as 12 days post-injection suggesting that SCCs do undergo turnover like the surrounding nasal epithelium. No BrdU labeled cells were detected after 24 days suggesting relatively rapid replacement of the SCCs.

Solitary Chemoreceptor Cell Proliferation in Adult Nasal Epithelium

PubMed Central

Gulbransen, Brian D.; Finger, Thomas E.

2008-01-01

Nasal trigeminal chemosensitivity in mice and rats is mediated in part by solitary chemoreceptor cells (SCCs) in the nasal epithelium (Finger et al., 2003). Many nasal SCCs express the G-protein α-gustducin as well as other elements of the bitter-taste signaling cascade including phospholipase Cβ2, TRPM5 and T2R bitter-taste receptors. While some populations of sensory cells are replaced throughout life (taste and olfaction), others are not (hair cells and carotid body chemoreceptors). These experiments were designed to test whether new SCCs are generated within the epithelium of adult mice. Wild type C57/B6 mice were injected with the thymidine analog 5-bromo-2'-deoxyuridine (BrdU) to label dividing cells. At various times after injection (1-40 days), the mice were perfused with 4% paraformaldehyde and prepared for dual-label immunocytochemistry. Double labeled cells were detected as early as 3 days post BrdU injection and remained for as long as 12 days post-injection suggesting that SCCs do undergo turnover like the surrounding nasal epithelium. No BrdU labeled cells were detected after 24 days suggesting relatively rapid replacement of the SCCs. PMID:16374713

Multidrug resistance-selective antiproliferative activity of Piper amide alkaloids and synthetic analogues.

PubMed

Wang, Yue-Hu; Goto, Masuo; Wang, Li-Ting; Hsieh, Kan-Yen; Morris-Natschke, Susan L; Tang, Gui-Hua; Long, Chun-Lin; Lee, Kuo-Hsiung

2014-10-15

Twenty-five amide alkaloids (1-25) from Piper boehmeriifolium and 10 synthetic amide alkaloid derivatives (39-48) were evaluated for antiproliferative activity against eight human tumor cell lines, including chemosensitive and multidrug-resistant (MDR) cell lines. The results suggested tumor type-selectivity. 1-[7-(3,4,5-Trimethoxyphenyl)heptanoyl]piperidine (46) exhibited the best inhibitory activity (IC50=4.94 μM) against the P-glycoprotein (P-gp)-overexpressing KBvin MDR sub-line, while it and all other tested compounds, except 9, were inactive (IC50 >40 μM) against MDA-MB-231 and SK-BR-3. Structure-activity relationships (SARs) indicated that (i) 3,4,5-trimethoxy phenyl substitution is critical for selectivity against KBvin, (ii) the 4-methoxy group in this pattern is crucial for antiproliferative activity, (iii) double bonds in the side chain are not needed for activity, and (iv), in arylalkenylacyl amide alkaloids, replacement of an isobutylamino group with pyrrolidin-1-yl or piperidin-1-yl significantly improved activity. Further study on Piper amides is warranted, particularly whether side chain length affects the ability to overcome the MDR cancer phenotype. Copyright © 2014 Elsevier Ltd. All rights reserved.

TRPA1 Channels in Drosophila and Honey Bee Ectoparasitic Mites Share Heat Sensitivity and Temperature-Related Physiological Functions

PubMed Central

Peng, Guangda; Kashio, Makiko; Li, Tianbang; Dong, Xiaofeng; Tominaga, Makoto; Kadowaki, Tatsuhiko

2016-01-01

The transient receptor potential cation channel, subfamily A, member 1 (TRPA1) is conserved between many arthropods, and in some has been shown to function as a chemosensor for noxious compounds. Activation of arthropod TRPA1 channels by temperature fluctuations has been tested in only a few insect species, and all of them were shown to be activated by heat. The recent identification of chemosensitive TRPA1 channels from two honey bee ectoparasitic mite species (VdTRPA1 and TmTRPA1) have provided an opportunity to study the temperature-dependent activation and the temperature-associated physiological functions of TRPA1 channels in non-insect arthropods. We found that both mite TRPA1 channels are heat sensitive and capable of rescuing the temperature-related behavioral defects of a Drosophila melanogaster trpA1 mutant. These results suggest that heat-sensitivity of TRPA1 could be conserved between many arthropods despite its amino acid sequence diversity. Nevertheless, the ankyrin repeats (ARs) 6 and 7 are well-conserved between six heat-sensitive arthropod TRPA1 channels and have critical roles for the heat activation of VdTRPA1. PMID:27761115

In vitro pyrogen test for toxic or immunomodulatory drugs.

PubMed

Daneshian, Mardas; Guenther, Armin; Wendel, Albrecht; Hartung, Thomas; von Aulock, Sonja

2006-06-30

Pyrogenic contaminations of some classes of injectable drugs, e.g. toxic or immunomodulatory as well as false-positive drugs, represent a major risk which cannot yet be excluded due to the limitations of current tests. Here we describe a modification of the In vitro Pyrogen Test termed AWIPT (Adsorb, Wash, In vitro Pyrogen Test), which addresses this problem by introducing a pre-incubation step in which pyrogenic contaminations in the test sample are adsorbed to albumin-coated beads. After rinsing, the beads are incubated with human whole blood and the release of the endogenous pyrogen interleukin-1beta is measured as a marker of pyrogenic activity. Intentional contaminations with lipopolysaccharide were retrieved from the chemotherapeutic agents paclitaxel, cisplatin and liposomal daunorubicin, the antibiotic gentamicin, the antifungal agent liposomal amphotericin B, and the corticosteroid prednisolone at lower dilutions than in the standard in vitro pyrogen test. This represents a promising new approach for the detection of pyrogenic contamination in drugs or in drugs containing interfering additives and should lead to improved safety levels.

The use and interpretation of in vitro data in regulatory toxicology: cosmetics, toiletries and household products.

PubMed

Indans, Ian

2002-02-28

There is currently a drive to eliminate animal testing for cosmetics, toiletries and household products; indeed, the European Union Cosmetics Directive aims to prohibit the use of experimental animals for the testing of finished cosmetic products after 2002. At present, national prohibitions are in place in the UK, Germany, Austria and the Netherlands, for the testing of finished cosmetic products and cosmetic ingredients. In the USA animal testing for certain types of finished products is mandatory. Against this background, the currently available regulatory in vitro tests comprise methods for eye irritation, skin corrosivity, genotoxicity, dermal penetration and photoirritation. The draft updates to the Organisation for Economic Co-operation and Development guidelines for eye and skin irritation advocate the use of in vitro or ex vivo methods prior to the commencement of animal studies. At present, testing for these endpoints cannot be completed in vitro, but potentially corrosive substances and products can be classified without the need for animal studies. Regulatory genotoxicity testing can be completed using only in vitro methods, provided that a clear negative outcome is obtained for each test. Data from dermal penetration studies may be used to refine risk assessments. Current developments in areas such as skin sensitisation and skin irritation promise that in the reasonably near future such information may be generated without the use of animals.

Retrospective analysis of the mutagenicity/genotoxicity data of the cosmetic ingredients present on the Annexes of the Cosmetic EU legislation (2000-12).

PubMed

Ates, Gamze; Doktorova, Tatyana Y; Pauwels, Marleen; Rogiers, Vera

2014-03-01

To evaluate the mutagenicity/genotoxicity of cosmetic ingredients at the regulatory level, usually a battery of three in vitro tests is applied. This battery, designed to be very sensitive, produces a high number of positive results, imposing the need for in vivo follow-up testing to clear the substance under study. In Europe, the use of experimental animals has become impossible for cosmetic ingredients due to the implementation of animal testing and marketing bans. Consequently, the possibility to 'de-risk' substances with positive in vitro results disappear and potentially safe cosmetic substances will be lost for the EU market unless currently used in vitro assays can be adapted or new non-animal mutagenicity/genotoxicity studies become available. Described strategies to improve the specificity of existing in vitro assays include optimisation of the used cell type and cytotoxicity assay and lowering of the applied top concentration. A reduction of the number of tests in the battery from three to two also has been suggested. In this study, the performance of the 'standard' in vitro mutagenicity/genotoxicity testing battery is analysed for a number of cosmetic ingredients. We composed a database with toxicological information on 249 cosmetic ingredients, mainly present on the Annexes of the European cosmetic legislation. Results revealed that the in vitro mutagenicity/genotoxicity tests showed a low specificity for the cosmetic ingredients concerned, comparable to the specificity published for chemicals. Non-confirmed or 'misleading' positive results amounted up to 93% for the in vitro test batteries. The cell type and top concentrations did not have a major impact on the specificity. With respect to cytotoxicity determinations, different end points were used, potentially leading to different testing concentrations, suggesting the need for a consensus in this matter. Overall, the results of this retrospective analysis point to an urgent need of better regulatory strategies to assess the potential mutagenicity/genotoxicity of cosmetic ingredients.

Ventilatory effects of gap junction blockade in the RTN in awake rats.

PubMed

Hewitt, Amy; Barrie, Rachel; Graham, Michael; Bogus, Kara; Leiter, J C; Erlichman, Joseph S

2004-12-01

We tested the hypothesis that carbenoxolone, a pharmacological inhibitor of gap junctions, would reduce the ventilatory response to CO(2) when focally perfused within the retrotrapezoid nucleus (RTN). We tested this hypothesis by measuring minute ventilation (V(E)), tidal volume (V(T)), and respiratory frequency (F(R)) responses to increasing concentrations of inspired CO(2) (Fi(CO(2)) = 0-8%) in rats during wakefulness. We confirmed that the RTN was chemosensitive by perfusing the RTN unilaterally with either acetazolamide (AZ; 10 microM) or hypercapnic artificial cerebrospinal fluid equilibrated with 50% CO(2) (pH approximately 6.5). Focal perfusion of AZ or hypercapnic aCSF increased V(E), V(T), and F(R) during exposure to room air. Carbenoxolone (300 microM) focally perfused into the RTN decreased V(E) and V(T) in animals <11 wk of age, but V(E) and V(T) were increased in animals >12 wk of age. Glyzyrrhizic acid, a congener of carbenoxolone, did not change V(E), V(T), or F(R) when focally perfused into the RTN. Carbenoxolone binds to the mineralocorticoid receptor, but spironolactone (10 microM) did not block the disinhibition of V(E) or V(T) in older animals when combined with carbenoxolone. Thus the RTN is a CO(2) chemosensory site in all ages tested, but the function of gap junctions in the chemosensory process varies substantially among animals of different ages: gap junctions amplify the ventilatory response to CO(2) in younger animals, but appear to inhibit the ventilatory response to CO(2) in older animals.

Selection of a discriminant and biorelevant in vitro dissolution test for the development of fenofibrate self-emulsifying lipid-based formulations.

PubMed

Pestieau, Aude; Krier, Fabrice; Brouwers, Adeline; Streel, Bruno; Evrard, Brigitte

2016-09-20

Fenofibrate, a BCS class II compound, has a low bioavailability especially when taken orally on an empty stomach. The challenge to find a new formulation for providing bioavailability, independent of food, is still ongoing. If the development of a suitable oral delivery formulation of BCS class II compounds is a frequent and great challenge to formulation scientists, the in vitro evaluation of these new formulations is also a great challenge. The purpose of this study was therefore to select an in vitro dissolution test that would be useful and as biorelevant as possible for the development of fenofibrate self-emulsifying lipid-based formulations. In this context, three different fenofibrate formulations, for which in vivo data are available in the literature, were tested using different dissolution tests until we found the one that was the most suitable. As part of this approach, we started with the simplest in vitro dissolution tests and progressed to tests that were increasingly more complex. The first tests were different single phase dissolution tests: a test under sink conditions based on the USP monograph, and different tests under non-sink conditions in non-biorelevant and biorelevant media. Given the inconclusive results obtained with these tests, biphasic dissolution systems were then tested: one with USP apparatus type II alone and another which combined USP apparatus types II and IV. This last combined test seemed the most suitable in vitro dissolution test for the development of the future fenofibrate lipid-based formulations we intend to develop in our own laboratory. Copyright © 2016 Elsevier B.V. All rights reserved.

In vitro metabolism and bioavailability tests for the predictive toxicology of endocrine active substances

EPA Science Inventory

Legislation and prospective legislative proposals internationally (may) require that chemicals are tested for their ability to disrupt the hormonal systems of animals. Chemicals found to test positive in vitro are considered to be endocrine active substances (EAS) and may be puta...

Alginate based 3D hydrogels as an in vitro co-culture model platform for the toxicity screening of new chemical entities.

PubMed

Lan, Shih-Feng; Starly, Binil

2011-10-01

Prediction of human response to potential therapeutic drugs is through conventional methods of in vitro cell culture assays and expensive in vivo animal testing. Alternatives to animal testing require sophisticated in vitro model systems that must replicate in vivo like function for reliable testing applications. Advancements in biomaterials have enabled the development of three-dimensional (3D) cell encapsulated hydrogels as in vitro drug screening tissue model systems. In this study, we have developed an in vitro platform to enable high density 3D culture of liver cells combined with a monolayer growth of target breast cancer cell line (MCF-7) in a static environment as a representative example of screening drug compounds for hepatotoxicity and drug efficacy. Alginate hydrogels encapsulated with serial cell densities of HepG2 cells (10(5)-10(8) cells/ml) are supported by a porous poly-carbonate disc platform and co-cultured with MCF-7 cells within standard cell culture plates during a 3 day study period. The clearance rates of drug transformation by HepG2 cells are measured using a coumarin based pro-drug. The platform was used to test for HepG2 cytotoxicity 50% (CT(50)) using commercially available drugs which further correlated well with published in vivo LD(50) values. The developed test platform allowed us to evaluate drug dose concentrations to predict hepatotoxicity and its effect on the target cells. The in vitro 3D co-culture platform provides a scalable and flexible approach to test multiple-cell types in a hybrid setting within standard cell culture plates which may open up novel 3D in vitro culture techniques to screen new chemical entity compounds. Copyright © 2011 Elsevier Inc. All rights reserved.

National Cancer Institute Pediatric Preclinical Testing Program: Model Description for In Vitro Cytotoxicity Testing

PubMed Central

Kang, Min H.; Smith, Malcolm A.; Morton, Christopher L.; Keshelava, Nino; Houghton, Peter J.; Reynolds, C. Patrick

2010-01-01

Background The National Cancer Institute (NCI) has established the Pediatric Preclinical Testing Program (PPTP) for testing drugs against in vitro and in vivo childhood cancer models to aid in the prioritization of drugs considered for early phase pediatric clinical trials. Procedures In vitro cytotoxicity testing employs a semi-automated fluorescence-based digital imaging cytotoxicity assay (DIMSCAN) that has a 4-log dynamic range of detection. Curve fitting of the fractional survival data of the cell lines in response to various concentrations of the agents was used to calculate relative IC50, absolute IC50, and Ymin values The panel of 23 pediatric cancer cell lines included leukemia (n=6), lymphoma (n=2), rhabdomyosarcoma (n=4), brain tumors (n=3), Ewing family of tumors (EFT, n=4), and neuroblastoma (n=4). The doubling times obtained using DIMSCAN were incorporated into data analyses to estimate the relationship between input cell numbers and final cell number. Results We report in vitro activity data for three drugs (vincristine, melphalan, and etoposide) that are commonly used for pediatric cancer and for the mTOR inhibitor rapamycin, an agent that is currently under preclinical investigation for cancer. To date, the PPTP has completed in vitro testing of 39 investigational and approved agents for single drug activity and two investigational agents in combination with various “standard” chemotherapy drugs. Conclusions This robust in vitro cytotoxicity testing system for pediatric cancers will enable comparisons to response data for novel agents obtained from xenograft studies and from clinical trials. PMID:20922763

Critical research gaps and translational priorities for the successful prevention and treatment of breast cancer

PubMed Central

2013-01-01

Introduction Breast cancer remains a significant scientific, clinical and societal challenge. This gap analysis has reviewed and critically assessed enduring issues and new challenges emerging from recent research, and proposes strategies for translating solutions into practice. Methods More than 100 internationally recognised specialist breast cancer scientists, clinicians and healthcare professionals collaborated to address nine thematic areas: genetics, epigenetics and epidemiology; molecular pathology and cell biology; hormonal influences and endocrine therapy; imaging, detection and screening; current/novel therapies and biomarkers; drug resistance; metastasis, angiogenesis, circulating tumour cells, cancer ‘stem’ cells; risk and prevention; living with and managing breast cancer and its treatment. The groups developed summary papers through an iterative process which, following further appraisal from experts and patients, were melded into this summary account. Results The 10 major gaps identified were: (1) understanding the functions and contextual interactions of genetic and epigenetic changes in normal breast development and during malignant transformation; (2) how to implement sustainable lifestyle changes (diet, exercise and weight) and chemopreventive strategies; (3) the need for tailored screening approaches including clinically actionable tests; (4) enhancing knowledge of molecular drivers behind breast cancer subtypes, progression and metastasis; (5) understanding the molecular mechanisms of tumour heterogeneity, dormancy, de novo or acquired resistance and how to target key nodes in these dynamic processes; (6) developing validated markers for chemosensitivity and radiosensitivity; (7) understanding the optimal duration, sequencing and rational combinations of treatment for improved personalised therapy; (8) validating multimodality imaging biomarkers for minimally invasive diagnosis and monitoring of responses in primary and metastatic disease; (9) developing interventions and support to improve the survivorship experience; (10) a continuing need for clinical material for translational research derived from normal breast, blood, primary, relapsed, metastatic and drug-resistant cancers with expert bioinformatics support to maximise its utility. The proposed infrastructural enablers include enhanced resources to support clinically relevant in vitro and in vivo tumour models; improved access to appropriate, fully annotated clinical samples; extended biomarker discovery, validation and standardisation; and facilitated cross-discipline working. Conclusions With resources to conduct further high-quality targeted research focusing on the gaps identified, increased knowledge translating into improved clinical care should be achievable within five years. PMID:24286369

Paclitaxel and the dietary flavonoid fisetin: a synergistic combination that induces mitotic catastrophe and autophagic cell death in A549 non-small cell lung cancer cells.

PubMed

Klimaszewska-Wisniewska, Anna; Halas-Wisniewska, Marta; Tadrowski, Tadeusz; Gagat, Maciej; Grzanka, Dariusz; Grzanka, Alina

2016-01-01

The use of the dietary polyphenols as chemosensitizing agents to enhance the efficacy of conventional cytostatic drugs has recently gained the attention of scientists and clinicians as a plausible approach for overcoming the limitations of chemotherapy (e.g. drug resistance and cytotoxicity). The aim of this study was to investigate whether a naturally occurring diet-based flavonoid, fisetin, at physiologically attainable concentrations, could act synergistically with clinically achievable doses of paclitaxel to produce growth inhibitory and/or pro-death effects on A549 non-small cell lung cancer cells, and if it does, what mechanisms might be involved. The drug-drug interactions were analyzed based on the combination index method of Chou and Talalay and the data from MTT assays. To provide some insights into the mechanism underlying the synergistic action of fisetin and paclitaxel, selected morphological, biochemical and molecular parameters were examined, including the morphology of cell nuclei and mitotic spindles, the pattern of LC3-II immunostaining, the formation of autophagic vacuoles at the electron and fluorescence microscopic level, the disruption of cell membrane asymmetry/integrity, cell cycle progression and the expression level of LC3-II, Bax, Bcl-2 and caspase-3 mRNA. Here, we reported the first experimental evidence for the existence of synergism between fisetin and paclitaxel in the in vitro model of non-small cell lung cancer. This synergism was, at least partially, ascribed to the induction of mitotic catastrophe. The switch from the cytoprotective autophagy to the autophagic cell death was also implicated in the mechanism of the synergistic action of fisetin and paclitaxel in the A549 cells. In addition, we revealed that the synergism between fisetin and paclitaxel was cell line-specific as well as that fisetin synergizes with arsenic trioxide, but not with mitoxantrone and methotrexate in the A549 cells. Our results provide rationale for further testing of fisetin in the combination with paclitaxel or arsenic trioxide to obtain detailed insights into the mechanism of their synergistic action as well as to evaluate their toxicity towards normal cells in an animal model in vivo. We conclude that this study is potentially interesting for the development of novel chemotherapeutic approach to non-small cell lung cancer.

Influence of drug loading and type of ointment base on the in vitro performance of acyclovir ophthalmic ointment.

PubMed

Al-Ghabeish, Manar; Xu, Xiaoming; Krishnaiah, Yellela S R; Rahman, Ziyaur; Yang, Yang; Khan, Mansoor A

2015-11-30

The availability of in vitro performance tests such as in vitro drug release testing (IVRT) and in vitro permeation testing (IVPT) are critical to comprehensively assure consistent delivery of the active component(s) from semisolid ophthalmic drug products. The objective was to study the impact of drug loading and type of ointment base on the in vitro performance (IVRT and IVPT) of ophthalmic ointments using acyclovir as a model drug candidate. The in vitro drug release for the ointments was evaluated using a modified USP apparatus 2 with Enhancer cells. The transcorneal permeation was carried out using rabbit cornea on modified vertical Franz cells. The drug retention in cornea (DRC) was also determined at the end of transcorneal drug permeation study. The in vitro drug release, transcorneal drug permeation as well as DRC exhibited a proportional increase with increasing drug loading in the ointment. On comparing the in vitro drug release profile with transcorneal permeation profile, it appears that drug release from the ointment is controlling acyclovir transport through the cornea. Furthermore, enhanced in vitro transcorneal permeation relative to the in vitro drug release underscores the importance of the interplay between the physiology of the ocular tissue and ointment formulation. The results indicated that IVRT and IVPT could be used to discriminate the impact of changes in drug load and formulation composition of ophthalmic ointments. Copyright © 2015. Published by Elsevier B.V.

Malignancy in Children with Trisomy 21

PubMed Central

Rabin, Karen R.; Whitlock, James A.

2009-01-01

Patients with Down syndrome (DS) display a unique spectrum of malignancies, with a 10 to 20-fold increased risk of acute leukemias, and a markedly decreased incidence of solid tumors. This review discusses current understanding of the basis for this distinctive pattern of cancer incidence, and the clinical and biologic features of the malignant disorders most frequent in DS: transient myeloproliferative disease, acute megakaryoblastic leukemia, and acute lymphoblastic leukemia. We also review distinctive pharmacogenetic issues, highlighting the differential chemosensitivity and toxicity profiles of DS patients compared to the general population; and epidemiologic studies of protective and adverse environmental risk factors for development of leukemia. PMID:19176633

A rational approach to the management of recurrent or persistent ovarian carcinoma.

PubMed

Thigpen, Tate

2012-03-01

Evidence supports the current paradigm for the management of patients with recurrent or persistent ovarian carcinoma. The paradigm requires that patients be classified as platinum-sensitive or platinum-resistant. Patients who achieve a complete response with platinum-based therapy and experience at least 6 months free from recurrence should be categorized as having chemosensitive disease and should be retreated with carboplatin-based doublets. Patients who progress while receiving treatment, whose best response is stable disease, or who experience a complete response of <6 months duration should be categorized as having chemoresistant disease and should be treated with a nonplatinum single agent.

Chemotherapy in metastatic retinoblastoma.

PubMed

Kingston, J E; Hungerford, J L; Plowman, P N

1987-03-01

Eleven children with metastatic retinoblastoma diagnosed during the period 1970-1984 were treated with chemotherapy. Short-term complete responses were observed in three children treated with a four-drug combination which included cisplatinum, and in one child treated with vincristine and cyclophosphamide. The median duration of survival of the 11 children receiving chemotherapy was nine months, whilst the median survival of 13 children with metastatic retinoblastoma who were not given chemotherapy was only 2.3 months (p = 0.06). This suggests that retinoblastoma is a chemosensitive tumour and therefore adjuvant chemotherapy may have a role in children with retinoblastoma who at diagnosis are thought to be at high risk of developing metastatic disease.

Growth factors and renal cancer: characterization and therapeutic implications.

PubMed

Mydlo, J H

1995-01-01

The heterogeneiety renal-cell carcinoma can lead to unpredictable behavior: the ability to achieve a large volume yet not metastasize, the ability to demonstrate late recurrence or spontaneous regression, or the capability to metastasize at a relatively small volume. One-third of all patients who undergo radical nephrectomy for presumed localized disease will eventually have metastasis. Since renal-cell carcinoma is not significantly radio- or chemosensitive, it is important to investigate new avenues for treatment of this tumor once it has spread, specifically at the molecular level. This review discusses the most recent work on growth factors and renal cancer and proposes possible modalities for treatment.

Epigenetic alterations as cancer diagnostic, prognostic, and predictive biomarkers.

PubMed

Deng, Dajun; Liu, Zhaojun; Du, Yantao

2010-01-01

Alterations of DNA methylation and transcription of microRNAs (miRNAs) are very stable phenomena in tissues and body fluids and suitable for sensitive detection. These advantages enable us to translate some important discoveries on epigenetic oncology into biomarkers for control of cancer. A few promising epigenetic biomarkers are emerging. Clinical trials using methylated CpG islands of p16, Septin9, and MGMT as biomarkers are carried out for predication of cancer development, diagnosis, and chemosensitivity. Circulating miRNAs are promising biomarkers, too. Breakthroughs in the past decade imply that epigenetic biomarkers may be useful in reducing the burden of cancer. Copyright © 2010 Elsevier Inc. All rights reserved.

Cephalosporins inhibit human metallo β-lactamase fold DNA repair nucleases SNM1A and SNM1B/apollo.

PubMed

Lee, Sook Y; Brem, Jürgen; Pettinati, Ilaria; Claridge, Timothy D W; Gileadi, Opher; Schofield, Christopher J; McHugh, Peter J

2016-05-10

Bacterial metallo-β-lactamases (MBLs) are involved in resistance to β-lactam antibiotics including cephalosporins. Human SNM1A and SNM1B are MBL superfamily exonucleases that play a key role in the repair of DNA interstrand cross-links, which are induced by antitumour chemotherapeutics, and are therefore targets for cancer chemosensitization. We report that cephalosporins are competitive inhibitors of SNM1A and SNM1B exonuclease activity; both the intact β-lactam and their hydrolysed products are active. This discovery provides a lead for the development of potent and selective SNM1A and SNM1B inhibitors.

Potential countersample materials for in vitro simulation wear testing.

PubMed

Shortall, Adrian C; Hu, Xiao Q; Marquis, Peter M

2002-05-01

Any laboratory investigation of the wear resistance of dental materials needs to consider oral conditions so that in vitro wear results can be correlated with in vivo findings. The choice of the countersample is a critical factor in establishing the pattern of tribological wear and in achieving an efficient in vitro wear testing system. This research investigated the wear behavior and surface characteristics associated with three candidate countersample materials used for in vitro wear testing in order to identify a possible suitable substitute for human dental enamel. Three candidate materials, stainless steel, steatite and dental porcelain were evaluated and compared to human enamel. A variety of factors including hardness, wear surface evolution and frictional coefficients were considered, relative to the tribology of the in vivo situation. The results suggested that the dental porcelain investigated bore the closest similarity to human enamel of the materials investigated. Assessment of potential countersample materials should be based on the essential tribological simulation supported by investigations of mechanical, chemical and structural properties. The selected dental porcelain had the best simulating ability among the three selected countersample materials and this class of material may be considered as a possible countersample material for in vitro wear test purposes. Further studies are required, employing a wider range of dental ceramics, in order to optimise the choice of countersample material for standardized in vitro wear testing.

In vitro metabolism and bioavailability tests for endocrine active substances: What is needed next for regulatory purposes?

EPA Science Inventory

Legistation and prospective legislative proposals internationally (may) require that chemicals be tested for their ability to disrupt the hormonal systems of mammals. Chemicals found to test positive in vitro are considered to be endocrine active substances (EAS) and may be puta...

Application of in vitro extraction studies to evaluate element bioaccessibility in soils from a transect across the United States and Canada

USGS Publications Warehouse

Morman, S.A.; Plumlee, G.S.; Smith, D.B.

2009-01-01

In vitro bioaccessibility tests (IVBA) are inexpensive, physiologically-based extraction tests designed to estimate the bioaccessibility of elements along ingestion exposure pathways. Published IVBA protocols call for the testing to be done on the Pb > Ni > As > Cr.

Correlation of In Vivo Versus In Vitro Benchmark Doses (BMDs) Derived From Micronucleus Test Data: A Proof of Concept Study.

PubMed

Soeteman-Hernández, Lya G; Fellows, Mick D; Johnson, George E; Slob, Wout

2015-12-01

In this study, we explored the applicability of using in vitro micronucleus (MN) data from human lymphoblastoid TK6 cells to derive in vivo genotoxicity potency information. Nineteen chemicals covering a broad spectrum of genotoxic modes of action were tested in an in vitro MN test using TK6 cells using the same study protocol. Several of these chemicals were considered to need metabolic activation, and these were administered in the presence of S9. The Benchmark dose (BMD) approach was applied using the dose-response modeling program PROAST to estimate the genotoxic potency from the in vitro data. The resulting in vitro BMDs were compared with previously derived BMDs from in vivo MN and carcinogenicity studies. A proportional correlation was observed between the BMDs from the in vitro MN and the BMDs from the in vivo MN assays. Further, a clear correlation was found between the BMDs from in vitro MN and the associated BMDs for malignant tumors. Although these results are based on only 19 compounds, they show that genotoxicity potencies estimated from in vitro tests may result in useful information regarding in vivo genotoxic potency, as well as expected cancer potency. Extension of the number of compounds and further investigation of metabolic activation (S9) and of other toxicokinetic factors would be needed to validate our initial conclusions. However, this initial work suggests that this approach could be used for in vitro to in vivo extrapolations which would support the reduction of animals used in research (3Rs: replacement, reduction, and refinement). © The Author 2015. Published by Oxford University Press on behalf of the Society of Toxicology.

MicroRNA-29b-1 impairs in vitro cell proliferation, self‑renewal and chemoresistance of human osteosarcoma 3AB-OS cancer stem cells.

PubMed

Di Fiore, Riccardo; Drago-Ferrante, Rosa; Pentimalli, Francesca; Di Marzo, Domenico; Forte, Iris Maria; D'Anneo, Antonella; Carlisi, Daniela; De Blasio, Anna; Giuliano, Michela; Tesoriere, Giovanni; Giordano, Antonio; Vento, Renza

2014-11-01

Osteosarcoma (OS) is the most common type of bone cancer, with a peak incidence in the early childhood. Emerging evidence suggests that treatments targeting cancer stem cells (CSCs) within a tumor can halt cancer and improve patient survival. MicroRNAs (miRNAs) have been implicated in the maintenance of the CSC phenotype, thus, identification of CSC-related miRNAs would provide information for a better understanding of CSCs. Downregulation of miRNA-29 family members (miR-29a/b/c; miR‑29s) was observed in human OS, however, little is known about the functions of miR-29s in human OS CSCs. Previously, during the characterization of 3AB-OS cells, a CSC line selected from human OS MG63 cells, we showed a potent downregulation of miR-29b. In this study, after stable transfection of 3AB-OS cells with miR-29b-1, we investigated the role of miR-29b-1 in regulating cell proliferation, sarcosphere-forming ability, clonogenic growth, chemosensitivity, migration and invasive ability of 3AB-OS cells, in vitro. We found that, miR-29b-1 overexpression consistently reduced both, 3AB-OS CSCs growth in two- and three-dimensional culture systems and their sarcosphere- and colony-forming ability. In addition, while miR-29b-1 overexpression sensitized 3AB-OS cells to chemotherapeutic drug-induced apoptosis, it did not influence their migratory and invasive capacities, thus suggesting a context-depending role of miR-29b-1. Using publicly available databases, we proceeded to identify potential miR-29b target genes, known to play a role in the above reported functions. Among these targets we analyzed CD133, N-Myc, CCND2, E2F1 and E2F2, Bcl-2 and IAP-2. We also analyzed the most important stemness markers as Oct3/4, Sox2 and Nanog. Real-time RT-PCR and western-blot analyses showed that miR-29b-1 negatively regulated the expression of these markers. Overall, the results show that miR-29b-1 suppresses stemness properties of 3AB-OS CSCs and suggest that developing miR-29b-1 as a novel therapeutic agent might offer benefits for OS treatment.

A new alternative method for testing skin irritation using a human skin model: a pilot study.

PubMed

Miles, A; Berthet, A; Hopf, N B; Gilliet, M; Raffoul, W; Vernez, D; Spring, P

2014-03-01

Studies assessing skin irritation to chemicals have traditionally used laboratory animals; however, such methods are questionable regarding their relevance for humans. New in vitro methods have been validated, such as the reconstructed human epidermis (RHE) model (Episkin®, Epiderm®). The comparison (accuracy) with in vivo results such as the 4-h human patch test (HPT) is 76% at best (Epiderm®). There is a need to develop an in vitro method that better simulates the anatomo-pathological changes encountered in vivo. To develop an in vitro method to determine skin irritation using human viable skin through histopathology, and compare the results of 4 tested substances to the main in vitro methods and in vivo animal method (Draize test). Human skin removed during surgery was dermatomed and mounted on an in vitro flow-through diffusion cell system. Ten chemicals with known non-irritant (heptylbutyrate, hexylsalicylate, butylmethacrylate, isoproturon, bentazon, DEHP and methylisothiazolinone (MI)) and irritant properties (folpet, 1-bromohexane and methylchloroisothiazolinone (MCI/MI)), a negative control (sodiumchloride) and a positive control (sodiumlaurylsulphate) were applied. The skin was exposed at least for 4h. Histopathology was performed to investigate irritation signs (spongiosis, necrosis, vacuolization). We obtained 100% accuracy with the HPT model; 75% with the RHE models and 50% with the Draize test for 4 tested substances. The coefficients of variation (CV) between our three test batches were <0.1, showing good reproducibility. Furthermore, we reported objectively histopathological irritation signs (irritation scale): strong (folpet), significant (1-bromohexane), slight (MCI/MI at 750/250ppm) and none (isoproturon, bentazon, DEHP and MI). This new in vitro test method presented effective results for the tested chemicals. It should be further validated using a greater number of substances; and tested in different laboratories in order to suitably evaluate reproducibility. Copyright © 2013 Elsevier Ltd. All rights reserved.

Assessment of the predictive capacity of the optimized in vitro comet assay using HepG2 cells.

PubMed

Hong, Yoon-Hee; Jeon, Hye Lyun; Ko, Kyung Yuk; Kim, Joohwan; Yi, Jung-Sun; Ahn, Ilyoung; Kim, Tae Sung; Lee, Jong Kwon

2018-03-01

Evaluation of DNA damage is critical during the development of new drugs because it is closely associated with genotoxicity and carcinogenicity. The in vivo comet assay to assess DNA damage is globally harmonized as OECD TG 489. However, a comet test guideline that evaluates DNA damage without sacrificing animals does not yet exist. The goal of this study was to select an appropriate cell line for optimization of the in vitro comet assay to assess DNA damage. We then evaluated the predictivity of the in vitro comet assay using the selected cell line. In addition, the effect of adding S9 was evaluated using 12 test chemicals. For cell line selection, HepG2, Chinese hamster lung (CHL/IU), and TK6 cell lines were evaluated. We employed a method for the in vitro comet assay based on that for the in vivo comet assay. The most appropriate cell line was determined by% tail DNA increase after performing in vitro comet assays with 6 test chemicals. The predictivity of the in vitro comet assay using the selected cell line was measured with 10 test chemicals (8 genotoxins and 2 non-genotoxic chemicals). The HepG2 cell line was found to be the most appropriate, and in vitro comet assays using HepG2 cells exhibited a high accuracy of 90% (9/10). This study suggests that HepG2 is an optimal cell line for the in vitro comet assay to assess DNA damage. Copyright © 2018 Elsevier B.V. All rights reserved.

Influence of niobium pentoxide addition on the properties of glass ionomer cements

PubMed Central

Garcia, Isadora Martini; Leitune, Vicente Castelo Branco; Balbinot, Gabriela De Souza; Samuel, Susana Maria Werner; Collares, Fabrício Mezzomo

2016-01-01

Abstract Objective: To determine the influence of niobium pentoxide (Nb2O5) addition on the physical and chemical properties of glass ionomer cements (GICs). Materials and methods: Five, 10 or 20 wt.% of Nb2O5 were incorporated into commercial GICs (Maxxion R, Vitro Molar, Vitro Fil R) and one group of each GIC remained without Nb2O5 (control groups). The GICs were evaluated by Knoop hardness, compressive strength, acid erosion, particle size and radiopacity. Data were analyzed by two-way ANOVA followed by Tukey's test. Results: The addition of 10% and 20% reduced the microhardness of two GICs (p < .05). Compressive strength showed no difference among groups (p > .05). Nb2O5 did not influence Maxxion R and Vitro Fil R regarding the acid erosion test (p > .05). Vitro Molar increased its acid erosion with 10% of Nb2O5 (p < .05). Maxxion R presented 15.78 μm, while Vitro Molar and Vitro Fil R showed 5.14 μm and 6.18 μm, respectively. As the Nb2O5 concentration increased, the radiopacity increased for all groups. Vitro Molar and Vitro Fil R did not present significant difference to at least 1 mm aluminum (p > .05). Conclusion: The addition of 5 wt.% Nb2O5 did not affect the tested physical and chemical properties of the GICs and improved the radiopacity of one of the cements. These materials are therefore suitable for further testing of biomimetic remineralization properties. PMID:28642924

Development of biomimetic in vitro fatigue assessment for UHMWPE implant materials.

PubMed

Scholz, Ronja; Knyazeva, Marina; Porchetta, Dario; Wegner, Nils; Senatov, Fedor; Salimon, Alexey; Kaloshkin, Sergey; Walther, Frank

2018-05-26

An important research goal in the field of biomaterials lies in the progressive amendment of in vivo tests with suitable in vitro experiments. Such approaches are gaining more significance nowadays because of an increasing demand on life sciences and the ethical issues bound to the sacrifice of animals for the sake of scientific research. Another advantage of transferring the experiments to the in vitro field is the possibility of accurately control the boundary conditions and experimental parameters in order to reduce the need of validation tests involving animals. With the aim to reduce the amount of needed in vivo studies for this cause, a short-time in vitro test procedure using instrumented load increase tests with superimposed environmental loading has been developed at TUD to assess the mechanical long-term durability of ultra-high molecular weight polyethylene (UHMWPE) under fatigue loading in a biological environment. Copyright © 2018 Elsevier Ltd. All rights reserved.

Phototoxicity to sulphonamide-derived oral antidiabetics and diuretics: comparative in-vitro and in-vivo investigations

NASA Astrophysics Data System (ADS)

Selvaag, Edgar; Anholt, Helle; Moan, Johan; Thune, Per

1997-12-01

Seven oral antidiabetics (chlorpropamide, glibenclamide, glipizide, gliquidone, glymidine, tolazamide, and tolbutamide), and 14 diuretics (bemetizide, bendroflumethiazide, benzylhydrochlorothiazide, bumetanide, butizide, chlortalidone, furosemide, hydrochlorothiazide, hydroflumethiazide, indapamide, piretanide, polythiazide, trichlormethiazide, and xipamide) were investigated for potential phototoxicity in vitro using a cell culture model and in vivo in hairless mice. After exposure to broad band UVA, the majority of the substances tested in vitro yielded phototoxic action leading to loss of culture forming ability. In vivo, all tested substances induced edema or ulceration, and lead to a significant increase in skin fold thickness of the mouse skin. In all a number of substances not described to induce clinical photosensitivity nor phototoxicity in vitro or in vivo were detected in our testing. In determining potential photosensitizers, it seems important to utilize different test methods, as not all substances will exhibit action in a given assay.

Informing Selection of Nanomaterial Concentrations for ToxCast In Vitro Testing using the Multiple-Path Particle Dosimetry Model - 3rd Annual International Conference on the Environmental Implications of NanoTechnology (ICEIN) & EPA Nano Grantees Meeting (2011)

EPA Science Inventory

Currently, little justification is provided for nanomaterial testing concentrations in in vitro assays. The in vitro concentrations typically used may be higher than those experienced by exposed humans. Selection of concentration levels for hazard evaluation based on real-world e...

Compounds used to produce cloned animals are genotoxic and mutagenic in mammalian assays in vitro and in vivo

PubMed Central

Oliveira, R.J.; Mantovani, M.S.; da Silva, A.F.; Pesarini, J.R.; Mauro, M.O.; Ribeiro, L.R.

2014-01-01

The compounds 6-dimethylaminopurine and cycloheximide promote the successful production of cloned mammals and have been used in the development of embryos produced by somatic cell nuclear transfer. This study investigated the effects of 6-dimethylaminopurine and cycloheximide in vitro, using the thiazolyl blue tetrazolium bromide colorimetric assay to assess cytotoxicity, the trypan blue exclusion assay to assess cell viability, the comet assay to assess genotoxicity, and the micronucleus test with cytokinesis block to test mutagenicity. In addition, the comet assay and the micronucleus test were also performed on peripheral blood cells of 54 male Swiss mice, 35 g each, to assess the effects of the compounds in vivo. The results indicated that both 6-dimethylaminopurine and cycloheximide, at the concentrations and doses tested, were cytotoxic in vitro and genotoxic and mutagenic in vitro and in vivo, altered the nuclear division index in vitro, but did not diminish cell viability in vitro. Considering that alterations in DNA play important roles in mutagenesis, carcinogenesis, and morphofunctional teratogenesis and reduce embryonic viability, this study indicated that 6-dimethylaminopurine and cycloheximide utilized in the process of mammalian cloning may be responsible for the low embryo viability commonly seen in nuclear transfer after implantation in utero. PMID:24714812

Compounds used to produce cloned animals are genotoxic and mutagenic in mammalian assays in vitro and in vivo.

PubMed

Oliveira, R J; Mantovani, M S; Silva, A F da; Pesarini, J R; Mauro, M O; Ribeiro, L R

2014-04-01

The compounds 6-dimethylaminopurine and cycloheximide promote the successful production of cloned mammals and have been used in the development of embryos produced by somatic cell nuclear transfer. This study investigated the effects of 6-dimethylaminopurine and cycloheximide in vitro, using the thiazolyl blue tetrazolium bromide colorimetric assay to assess cytotoxicity, the trypan blue exclusion assay to assess cell viability, the comet assay to assess genotoxicity, and the micronucleus test with cytokinesis block to test mutagenicity. In addition, the comet assay and the micronucleus test were also performed on peripheral blood cells of 54 male Swiss mice, 35 g each, to assess the effects of the compounds in vivo. The results indicated that both 6-dimethylaminopurine and cycloheximide, at the concentrations and doses tested, were cytotoxic in vitro and genotoxic and mutagenic in vitro and in vivo, altered the nuclear division index in vitro, but did not diminish cell viability in vitro. Considering that alterations in DNA play important roles in mutagenesis, carcinogenesis, and morphofunctional teratogenesis and reduce embryonic viability, this study indicated that 6-dimethylaminopurine and cycloheximide utilized in the process of mammalian cloning may be responsible for the low embryo viability commonly seen in nuclear transfer after implantation in utero.

In vitro pituitary and thyroid cell proliferation assays and their relevance as alternatives to animal testing.

PubMed

Jomaa, Barae; Aarts, Jac M M J G; de Haan, Laura H J; Peijnenburg, Ad A C M; Bovee, Toine F H; Murk, Albertinka J; Rietjens, Ivonne M C M

2013-01-01

This study investigates the in vitro effect of eleven thyroid-active compounds known to affect pituitary and/or thyroid weights in vivo, using the proliferation of GH3 rat pituitary cells in the so-called "T-screen," and of FRTL-5 rat thyroid cells in a newly developed test denoted "TSH-screen" to gain insight into the relative value of these in vitro proliferation tests for an integrated testing strategy (ITS) for thyroid activity. Pituitary cell proliferation in the T-screen was stimulated by three out of eleven tested compounds, namely thyrotropin releasing hormone (TRH), triiodothyronine (T3) and thyroxine (T4). Of these three compounds, only T4 causes an increase in relative pituitary weight, and thus T4 was the only compound for which the effect in the in vitro assay correlated with a reported in vivo effect. As to the newly developed TSH-screen, two compounds had an effect, namely, thyroid-stimulating hormone (TSH) induced and T4 antagonized FRTL-5 cell proliferation. These effects correlated with in vivo changes induced by these compounds on thyroid weight. Altogether, the results indicate that most of the selected compounds affect pituitary and thyroid weights by modes of action different from a direct thyroid hormone receptor (THR) or TSH receptor (TSHR)-mediated effect, and point to the need for additional in vitro tests for an ITS. Additional analysis of the T-screen revealed a positive correlation between the THR-mediated effects of the tested compounds in vitro and their effects on relative heart weight in vivo, suggesting that the T-screen may directly predict this THR-mediated in vivo adverse effect.

76 FR 29752 - Nomination of In Vitro Test Methods for Detection and Quantification of Botulinum Neurotoxins and...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-23

... DEPARTMENT OF HEALTH AND HUMAN SERVICES Nomination of In Vitro Test Methods for Detection and... Evaluated by These Test Methods AGENCY: Division of National Toxicology Program (NTP), National Institute of... Methods (ICCVAM), the NTP Interagency Center for the Evaluation of Alternative Toxicological Methods...

77 FR 8258 - Availability of ICCVAM Evaluation Report and Recommendations on the Usefulness and Limitations of...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-02-14

... development of BG1Luc ER TA test method performance standards. ICCVAM assigned the activities a high priority... Vitro Test Methods for Detecting Potential Endocrine Disruptors. Research Triangle Park, NC: National...Final.pdf . ICCVAM. 2003a. ICCVAM Evaluation of In Vitro Test Methods For Detecting Potential Endocrine...

Possible strategies for EDC testing in the future: exploring roles of pathway-based in silico, in vitro and in vivo methods

EPA Science Inventory

Current methods for screening, testing and monitoring endocrine-disrupting chemicals (EDCs) rely relatively substantially upon moderate- to long-term assays that can, in some instances, require significant numbers of animals. Recent developments in the areas of in vitro testing...

The resolving power of in vitro genotoxicity assays for cigarette smoke particulate matter.

PubMed

Scott, K; Saul, J; Crooks, I; Camacho, O M; Dillon, D; Meredith, C

2013-06-01

In vitro genotoxicity assays are often used to compare tobacco smoke particulate matter (PM) from different cigarettes. The quantitative aspect of the comparisons requires appropriate statistical methods and replication levels, to support the interpretation in terms of power and significance. This paper recommends a uniform statistical analysis for the Ames test, mouse lymphoma mammalian cell mutation assay (MLA) and the in vitro micronucleus test (IVMNT); involving a hierarchical decision process with respect to slope, fixed effect and single dose comparisons. With these methods, replication levels of 5 (Ames test TA98), 4 (Ames test TA100), 10 (Ames test TA1537), 6 (MLA) and 4 (IVMNT) resolved a 30% difference in PM genotoxicity. Copyright © 2013 Elsevier Ltd. All rights reserved.

In vitro tests for drug hypersensitivity reactions: an ENDA/EAACI Drug Allergy Interest Group position paper.

PubMed

Mayorga, C; Celik, G; Rouzaire, P; Whitaker, P; Bonadonna, P; Rodrigues-Cernadas, J; Vultaggio, A; Brockow, K; Caubet, J C; Makowska, J; Nakonechna, A; Romano, A; Montañez, M I; Laguna, J J; Zanoni, G; Gueant, J L; Oude Elberink, H; Fernandez, J; Viel, S; Demoly, P; Torres, M J

2016-08-01

Drug hypersensitivity reactions (DHRs) are a matter of great concern, both for outpatient and in hospital care. The evaluation of these patients is complex, because in vivo tests have a suboptimal sensitivity and can be time-consuming, expensive and potentially risky, especially drug provocation tests. There are several currently available in vitro methods that can be classified into two main groups: those that help to characterize the active phase of the reaction and those that help to identify the culprit drug. The utility of these in vitro methods depends on the mechanisms involved, meaning that they cannot be used for the evaluation of all types of DHRs. Moreover, their effectiveness has not been defined by a consensus agreement between experts in the field. Thus, the European Network on Drug Allergy and Drug Allergy Interest Group of the European Academy of Allergy and Clinical Immunology has organized a task force to provide data and recommendations regarding the available in vitro methods for DHR diagnosis. We have found that although there are many in vitro tests, few of them can be given a recommendation of grade B or above mainly because there is a lack of well-controlled studies, most information comes from small studies with few subjects and results are not always confirmed in later studies. Therefore, it is necessary to validate the currently available in vitro tests in a large series of well-characterized patients with DHR and to develop new tests for diagnosis. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Cytosine arabinoside, vinblastine, 5-fluorouracil and 2-aminoanthracene testing in the in vitro micronucleus assay with L5178Y mouse lymphoma cells at Sanofi Aventis, with different cytotoxicity measurements, in support of the draft OECD Test Guideline on In Vitro Mammalian Cell Micronucleus Test.

PubMed

Cariou, Olivier; Laroche-Prigent, Nathalie; Ledieu, Sandrine; Guizon, Isabelle; Paillard, Françoise; Thybaud, Véronique

2010-10-29

Cytosine arabinoside (a nucleoside analogue that inhibits the gap-filling step of excision repair), vinblastine (an aneugen that inhibits tubulin polymerisation), 5-fluorouracil (a nucleoside analogue with a steep response profile), and 2-aminoanthracene (a metabolism-dependent reference genotoxin) were tested in the in vitro micronucleus assay with L5178Y mouse lymphoma cells, without cytokinesis block. The four chemicals were independently evaluated in two Sanofi Aventis laboratories, one of which used an image analyser to score micronuclei, while the other scored micronucleated cells manually. Very similar results were obtained in the two laboratories, highlighting the robustness of the assay. The four test chemicals induced significant increases in the incidence of micronucleated cells at concentrations that produced no more than a 55±5% reduction in survival growth, as measured with the three parameters recommended in the draft OECD Test Guideline on In Vitro Mammalian Cell Micronucleus Test (MNvit) for chemical testing, namely the relative increase in cell counts, relative population doubling, and the relative cell count. These results support the premise that the relative increase in cell counts and relative population doubling, that take into account both cell death and cytostasis, are appropriate measures of survival growth reduction in the in vitro micronucleus test conducted in the absence of cytokinesis block, as recommended in MNvit. Copyright © 2010 Elsevier B.V. All rights reserved.

Comparison of in vivo and in vitro survival and fecundity rates of the poultry red mite, Dermanyssus gallinae.

PubMed

Arkle, S; George, D R; Guy, J H; Sparagano, O A E

2010-04-01

To assist in the testing of possible antigens in developing a vaccine against the poultry red mite (Dermanyssus gallinae De Geer), a rapid and reliable in vitro screening method is critical. This short paper describes how D. gallinae survival and fecundity rates in an in vivo feeding device compared to that of mites fed using an in vitro method. Results showed that survival of fed D. gallinae females and mites overall was greater in vitro, although there was no difference between male survival and fecundity between in vivo and in vitro designs. The in vitro feeding device described therefore has the potential to provide reliable results, comparable to those obtained by in vivo testing, to allow for the rapid screening of D. gallinae antigens. Copyright 2009 Elsevier Ltd. All rights reserved.

Evaluation of the sensitivity and specificity of in vivo erythrocyte micronucleus and transgenic rodent gene mutation tests to detect rodent carcinogens.

PubMed

Morita, Takeshi; Hamada, Shuichi; Masumura, Kenichi; Wakata, Akihiro; Maniwa, Jiro; Takasawa, Hironao; Yasunaga, Katsuaki; Hashizume, Tsuneo; Honma, Masamitsu

2016-05-01

Sensitivity and/or specificity of the in vivo erythrocyte micronucleus (MN) and transgenic rodent mutation (TGR) tests to detect rodent carcinogens and non-carcinogens were investigated. The Carcinogenicity and Genotoxicity eXperience (CGX) dataset created by Kirkland et al. was used for the carcinogenicity and in vitro genotoxicity data, i.e., Ames and chromosome aberration (CA) tests. Broad literature surveys were conducted to gather in vivo MN or TGR test data to add to the CGX dataset. Genotoxicity data in vitro were also updated slightly. Data on 379 chemicals (293 carcinogens and 86 non-carcinogens) were available for the in vivo MN test; sensitivity, specificity or concordances were calculated as 41.0%, 60.5% or 45.4%, respectively. For the TGR test, data on 80 chemicals (76 carcinogens and 4 non-carcinogens) were available; sensitivity was calculated as 72.4%. Based on the recent guidance on genotoxicity testing strategies, performance (sensitivity/specificity) of the following combinations was calculated; Ames+in vivo MN (68.7%/45.3%), Ames+TGR (83.8%/not calculated (nc)), Ames+in vitro CA+in vivo MN (80.8%/21.3%), Ames+in vitro CA+TGR (89.1%/nc), Ames+in vivo MN+TGR (87.5%/nc), Ames+in vitro CA+in vivo MN+TGR (89.3%/nc). Relatively good balance in performance was shown by the Ames+in vivo MN in comparison with Ames+in vitro CA (74.3%/37.5%). Ames+TGR and Ames+in vivo MN+TGR gave even higher sensitivity, but the specificity could not be calculated (too few TGR data on non-carcinogens). This indicates that in vivo MN and TGR tests are both useful as in vivo tests to detect rodent carcinogens. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Recent advances in testing of microsphere drug delivery systems.

PubMed

Andhariya, Janki V; Burgess, Diane J

2016-01-01

This review discusses advances in the field of microsphere testing. In vitro release-testing methods such as sample and separate, dialysis membrane sacs and USP apparatus IV have been used for microspheres. Based on comparisons of these methods, USP apparatus IV is currently the method of choice. Accelerated in vitro release tests have been developed to shorten the testing time for quality control purposes. In vitro-in vivo correlations using real-time and accelerated release data have been developed, to minimize the need to conduct in vivo performance evaluation. Storage stability studies have been conducted to investigate the influence of various environmental factors on microsphere quality throughout the product shelf life. New tests such as the floating test and the in vitro wash-off test have been developed along with advancement in characterization techniques for other physico-chemical parameters such as particle size, drug content, and thermal properties. Although significant developments have been made in microsphere release testing, there is still a lack of guidance in this area. Microsphere storage stability studies should be extended to include microspheres containing large molecules. An agreement needs to be reached on the use of particle sizing techniques to avoid inconsistent data. An approach needs to be developed to determine total moisture content of microspheres.

In vitro genotoxicity testing strategy for nanomaterials and the adaptation of current OECD guidelines

PubMed Central

Doak, S.H.; Manshian, B.; Jenkins, G.J.S.; Singh, N.

2012-01-01

There is a pressing requirement to define a hazard identification and risk management strategy for nanomaterials due to the rapid growth in the nanotechnology industry and their promise of life-style revolutions through the development of wide-ranging nano-containing consumer products. Consequently, a battery of well defined and appropriate in vitro assays to assess a number of genotoxicity endpoints is required to minimise extensive and costly in vivo testing. However, the validity of the established protocols in current OECD recognised genotoxicity assays for nanomaterials is currently being questioned. In this report, we therefore consider the in vitro OECD genotoxicity test battery including the Ames, micronucleus and HPRT forward mutation assays, and their potential role in the safety assessment of nanomaterial induced DNA damage in vitro. PMID:21971291

Trends in the development of microfluidic cell biochips for in vitro hepatotoxicity.

PubMed

Baudoin, Régis; Corlu, Anne; Griscom, Laurent; Legallais, Cécile; Leclerc, Eric

2007-06-01

Current developments in the technological fields of liver tissue engineering, bioengineering, biomechanics, microfabrication and microfluidics have lead to highly complex and pertinent new tools called "cell biochips" for in vitro toxicology. The purpose of "cell biochips" is to mimic organ tissues in vitro in order to partially reduce the amount of in vivo testing. These "cell biochips" consist of microchambers containing engineered tissue and living cell cultures interconnected by a microfluidic network, which allows the control of microfluidic flows for dynamic cultures, by continuous feeding of nutrients to cultured cells and waste removal. Cell biochips also allow the control of physiological contact times of diluted molecules with the tissues and cells, for rapid testing of sample preparations or specific addressing. Cell biochips can be situated between in vitro and in vivo testing. These types of systems can enhance functionality of cells by mimicking the tissue architecture complexities when compared to in vitro analysis but at the same time present a more rapid and simple process when compared to in vivo testing procedures. In this paper, we first introduce the concepts of microfluidic and biochip systems based on recent progress in microfabrication techniques used to mimic liver tissue in vitro. This includes progress and understanding in biomaterials science (cell culture substrate), biomechanics (dynamic cultures conditions) and biology (tissue engineering). The development of new "cell biochips" for chronic toxicology analysis of engineered tissues can be achieved through the combination of these research domains. Combining these advanced research domains, we then present "cell biochips" that allow liver chronic toxicity analysis in vitro on engineered tissues. An extension of the "cell biochip" idea has also allowed "organ interactions on chip", which can be considered as a first step towards the replacement of animal testing using a combined liver/lung organ model.

Cytotoxicity assays with fish cells as an alternative to the acute lethality test with fish.

PubMed

Segner, Helmut

2004-10-01

In ecotoxicology, in vitro assays with fish cells are currently applied for mechanistic studies, bioanalytical purposes and toxicity screening. This paper discusses the potential of cytotoxicity assays with fish cells to reduce, refine or replace acute lethality tests using fish. Basal cytotoxicity data obtained with fish cell lines or fish primary cell cultures show a reasonable to good correlation with lethality data from acute toxicity tests, with the exception of compounds that exert a specific mode of toxic action. Basal cytotoxicity data from fish cell lines also correlate well with cytotoxicity data from mammalian cell lines. However, both the piscine and mammalian in vitro assays are clearly less sensitive than the fish test. Therefore, in vivo LC50 values (concentrations of the test compounds that are lethal to 50% of the fish in the experiment within 96 hours) currently cannot be predicted from in vitro values. This in vitro-in vivo difference in sensitivity appears to be true for both fish cell lines and mammalian cell lines. Given the good in vitro-in vivo correlation in toxicity ranking, together with the clear-cut difference in sensitivity, the role of cytotoxicity assays in a tiered alternative testing strategy could be in priority setting in relation to toxic hazard and in the toxicity classification of chemicals and environmental samples.

In vitro validation of a novel mechanical model for testing the anchorage capacity of pedicle screws using physiological load application.

PubMed

Liebsch, Christian; Zimmermann, Julia; Graf, Nicolas; Schilling, Christoph; Wilke, Hans-Joachim; Kienle, Annette

2018-01-01

Biomechanical in vitro tests analysing screw loosening often include high standard deviations caused by high variabilities in bone mineral density and pedicle geometry, whereas standardized mechanical models made of PU foam often do not integrate anatomical or physiological boundary conditions. The purpose of this study was to develop a most realistic mechanical model for the standardized and reproducible testing of pedicle screws regarding the resistance against screw loosening and the holding force as well as to validate this model by in vitro experiments. The novel mechanical testing model represents all anatomical structures of a human vertebra and is consisting of PU foam to simulate cancellous bone, as well as a novel pedicle model made of short carbon fibre filled epoxy. Six monoaxial cannulated pedicle screws (Ø6.5 × 45mm) were tested using the mechanical testing model as well as human vertebra specimens by applying complex physiological cyclic loading (shear, tension, and bending; 5Hz testing frequency; sinusoidal pulsating forces) in a dynamic materials testing machine with stepwise increasing load after each 50.000 cycles (100.0N shear force + 20.0N per step, 51.0N tension force + 10.2N per step, 4.2Nm bending moment + 0.8Nm per step) until screw loosening was detected. The pedicle screw head was fixed on a firmly clamped rod while the load was applied in the vertebral body. For the in vitro experiments, six human lumbar vertebrae (L1-3, BMD 75.4 ± 4.0mg/cc HA, pedicle width 9.8 ± 0.6mm) were tested after implanting pedicle screws under X-ray control. Relative motions of pedicle screw, specimen fixture, and rod fixture were detected using an optical motion tracking system. Translational motions of the mechanical testing model experiments in the point of load introduction (0.9-2.2mm at 240N shear force) were reproducible within the variation range of the in vitro experiments (0.6-3.5mm at 240N shear force). Screw loosening occurred continuously in each case between 140N and 280N, while abrupt failures of the specimen were observed only in vitro. In the mechanical testing model, no translational motion was detected in the screw entry point, while in vitro, translational motions of up to 2.5mm in inferior direction were found, leading to a slight shift of the centre of rotation towards the screw tip. Translational motions of the screw tip of about 5mm in superior direction were observed both in vitro and in the mechanical testing model, while they were continuous in the mechanical testing model and rapidly increasing after screw loosening initiation in vitro. The overall pedicle screw loosening characteristics were qualitatively and quantitatively similar between the mechanical testing model and the human vertebral specimens as long as there was no translation of the screw at the screw entrance point. Therefore, the novel mechanical testing model represents a promising method for the standardized testing of pedicle screws regarding screw loosening for cases where the screw rotates around a point close to the screw entry point. Copyright © 2017 Elsevier Ltd. All rights reserved.

Prevalidation of an Acute Inhalation Toxicity Test Using the EpiAirway In Vitro Human Airway Model

PubMed Central

Jackson, George R.; Maione, Anna G.; Klausner, Mitchell

2018-01-01

Abstract Introduction: Knowledge of acute inhalation toxicity potential is important for establishing safe use of chemicals and consumer products. Inhalation toxicity testing and classification procedures currently accepted within worldwide government regulatory systems rely primarily on tests conducted in animals. The goal of the current work was to develop and prevalidate a nonanimal (in vitro) test for determining acute inhalation toxicity using the EpiAirway™ in vitro human airway model as a potential alternative for currently accepted animal tests. Materials and Methods: The in vitro test method exposes EpiAirway tissues to test chemicals for 3 hours, followed by measurement of tissue viability as the test endpoint. Fifty-nine chemicals covering a broad range of toxicity classes, chemical structures, and physical properties were evaluated. The in vitro toxicity data were utilized to establish a prediction model to classify the chemicals into categories corresponding to the currently accepted Globally Harmonized System (GHS) and the Environmental Protection Agency (EPA) system. Results: The EpiAirway prediction model identified in vivo rat-based GHS Acute Inhalation Toxicity Category 1–2 and EPA Acute Inhalation Toxicity Category I–II chemicals with 100% sensitivity and specificity of 43.1% and 50.0%, for GHS and EPA acute inhalation toxicity systems, respectively. The sensitivity and specificity of the EpiAirway prediction model for identifying GHS specific target organ toxicity-single exposure (STOT-SE) Category 1 human toxicants were 75.0% and 56.5%, respectively. Corrosivity and electrophilic and oxidative reactivity appear to be the predominant mechanisms of toxicity for the most highly toxic chemicals. Conclusions: These results indicate that the EpiAirway test is a promising alternative to the currently accepted animal tests for acute inhalation toxicity. PMID:29904643

Prevalidation of an Acute Inhalation Toxicity Test Using the EpiAirway In Vitro Human Airway Model.

PubMed

Jackson, George R; Maione, Anna G; Klausner, Mitchell; Hayden, Patrick J

2018-06-01

Introduction: Knowledge of acute inhalation toxicity potential is important for establishing safe use of chemicals and consumer products. Inhalation toxicity testing and classification procedures currently accepted within worldwide government regulatory systems rely primarily on tests conducted in animals. The goal of the current work was to develop and prevalidate a nonanimal ( in vitro ) test for determining acute inhalation toxicity using the EpiAirway™ in vitro human airway model as a potential alternative for currently accepted animal tests. Materials and Methods: The in vitro test method exposes EpiAirway tissues to test chemicals for 3 hours, followed by measurement of tissue viability as the test endpoint. Fifty-nine chemicals covering a broad range of toxicity classes, chemical structures, and physical properties were evaluated. The in vitro toxicity data were utilized to establish a prediction model to classify the chemicals into categories corresponding to the currently accepted Globally Harmonized System (GHS) and the Environmental Protection Agency (EPA) system. Results: The EpiAirway prediction model identified in vivo rat-based GHS Acute Inhalation Toxicity Category 1-2 and EPA Acute Inhalation Toxicity Category I-II chemicals with 100% sensitivity and specificity of 43.1% and 50.0%, for GHS and EPA acute inhalation toxicity systems, respectively. The sensitivity and specificity of the EpiAirway prediction model for identifying GHS specific target organ toxicity-single exposure (STOT-SE) Category 1 human toxicants were 75.0% and 56.5%, respectively. Corrosivity and electrophilic and oxidative reactivity appear to be the predominant mechanisms of toxicity for the most highly toxic chemicals. Conclusions: These results indicate that the EpiAirway test is a promising alternative to the currently accepted animal tests for acute inhalation toxicity.

Proof of concept testing of a positive reference material for in vivo and in vitro skin irritation testing.

PubMed

Nomura, Yusuke; Lee, Michelle; Fukui, Chie; Watanabe, Kayo; Olsen, Daniel; Turley, Audrey; Morishita, Yuki; Kawakami, Tsuyoshi; Yuba, Toshiyasu; Fujimaki, Hideo; Inoue, Kaoru; Yoshida, Midori; Ogawa, Kumiko; Haishima, Yuji

2017-12-11

In vivo and in vitro irritation testing is important for evaluating the biological safety of medical devices. Here, the performance of positive reference materials for skin irritation testing was evaluated. Four reference standards, referred to as Y-series materials, were analyzed: a polyvinyl chloride (PVC) sheet spiked with 0 (Y-1), 1.0 (Y-2), 1.5 (Y-3), or 10 (Y-4) parts of Genapol X-080 per 100 parts of PVC by weight. Y-1, Y-2, and Y-3 did not induce skin irritation responses in an in vitro reconstructed human epidermis (RhE) tissue model, as measured by tissue viability or interleukin-1α release, or in an in vivo intracutaneous response test using rabbits. In contrast, Y-4 extracts prepared with saline or sesame oil at 37°C and 50°C clearly elicited positive irritation responses, including reduced viability (< 50%) and significantly higher interleukin-1α release compared with the solvent alone group, in the RhE tissue model and an intracutaneous response test, where substantial necrosis was observed by histopathology. The positive skin irritation responses induced in vitro under various extraction conditions, as well as those elicited in vivo, indicate that Y-4 is an effective extractable positive control material for in vivo and in vitro skin irritation tests of medical devices. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2017. © 2017 Wiley Periodicals, Inc.

A tiered approach to the use of alternatives to animal testing for the safety assessment of cosmetics: genotoxicity. A COLIPA analysis.

PubMed

Pfuhler, Stefan; Kirst, Annette; Aardema, Marilyn; Banduhn, Norbert; Goebel, Carsten; Araki, Daisuke; Costabel-Farkas, Margit; Dufour, Eric; Fautz, Rolf; Harvey, James; Hewitt, Nicola J; Hibatallah, Jalila; Carmichael, Paul; Macfarlane, Martin; Reisinger, Kerstin; Rowland, Joanna; Schellauf, Florian; Schepky, Andreas; Scheel, Julia

2010-01-01

For the assessment of genotoxic effects of cosmetic ingredients, a number of well-established and regulatory accepted in vitro assays are in place. A caveat to the use of these assays is their relatively low specificity and high rate of false or misleading positive results. Due to the 7th amendment to the EU Cosmetics Directive ban on in vivo genotoxicity testing for cosmetics that was enacted March 2009, it is no longer possible to conduct follow-up in vivo genotoxicity tests for cosmetic ingredients positive in in vitro genotoxicity tests to further assess the relevance of the in vitro findings. COLIPA, the European Cosmetics Association, has initiated a research programme to improve existing and develop new in vitro methods. A COLIPA workshop was held in Brussels in April 2008 to analyse the best possible use of available methods and approaches to enable a sound assessment of the genotoxic hazard of cosmetic ingredients. Common approaches of cosmetic companies are described, with recommendations for evaluating in vitro genotoxins using non-animal approaches. A weight of evidence approach was employed to set up a decision-tree for the integration of alternative methods into tiered testing strategies. Copyright 2010 Elsevier Inc. All rights reserved.