WorldWideScience

Sample records for cancer cell sensitivity

  1. Gene sensitizes cancer cells to chemotherapy drugs

    Science.gov (United States)

    NCI scientists have found that a gene, Schlafen-11 (SLFN11), sensitizes cells to substances known to cause irreparable damage to DNA.  As part of their study, the researchers used a repository of 60 cell types to identify predictors of cancer cell respons

  2. PCTAIRE1-knockdown sensitizes cancer cells to TNF family cytokines.

    Directory of Open Access Journals (Sweden)

    Teruki Yanagi

    Full Text Available While PCTAIRE1/PCTK1/Cdk16 is overexpressed in malignant cells and is crucial in tumorigenesis, its function in apoptosis remains unclear. Here we investigated the role of PCTAIRE1 in apoptosis, especially in the extrinsic cell death pathway. Gene-knockdown of PCTAIRE1 sensitized prostate cancer PPC1 and Du145 cells, and breast cancer MDA-MB-468 cells to TNF-family cytokines, including TNF-related apoptosis-inducing ligand (TRAIL. Meanwhile, PCTAIRE1-knockdown did not sensitize non-malignant cells, including diploid fibroblasts IMR-90 and the immortalized prostate epithelial cell line 267B1. PCTAIRE1-knockdown did not up-regulate death receptor expression on the cell surface or affect caspase-8, FADD and FLIP expression levels. PCTAIRE1-knockdown did promote caspase-8 cleavage and RIPK1 degradation, while RIPK1 mRNA knockdown sensitized PPC1 cells to TNF-family cytokines. Furthermore, the kinase inhibitor SNS-032, which inhibits PCTAIRE1 kinase activity, sensitized PPC1 cells to TRAIL-induced apoptosis. Together these results suggest that PCTAIRE1 contributes to the resistance of cancer cell lines to apoptosis induced by TNF-family cytokines, which implies that PCTAIRE1 inhibitors could have synergistic effects with TNF-family cytokines for cytodestruction of cancer cells.

  3. PCTAIRE1-knockdown sensitizes cancer cells to TNF family cytokines.

    Science.gov (United States)

    Yanagi, Teruki; Shi, Ranxin; Aza-Blanc, Pedro; Reed, John C; Matsuzawa, Shu-ichi

    2015-01-01

    While PCTAIRE1/PCTK1/Cdk16 is overexpressed in malignant cells and is crucial in tumorigenesis, its function in apoptosis remains unclear. Here we investigated the role of PCTAIRE1 in apoptosis, especially in the extrinsic cell death pathway. Gene-knockdown of PCTAIRE1 sensitized prostate cancer PPC1 and Du145 cells, and breast cancer MDA-MB-468 cells to TNF-family cytokines, including TNF-related apoptosis-inducing ligand (TRAIL). Meanwhile, PCTAIRE1-knockdown did not sensitize non-malignant cells, including diploid fibroblasts IMR-90 and the immortalized prostate epithelial cell line 267B1. PCTAIRE1-knockdown did not up-regulate death receptor expression on the cell surface or affect caspase-8, FADD and FLIP expression levels. PCTAIRE1-knockdown did promote caspase-8 cleavage and RIPK1 degradation, while RIPK1 mRNA knockdown sensitized PPC1 cells to TNF-family cytokines. Furthermore, the kinase inhibitor SNS-032, which inhibits PCTAIRE1 kinase activity, sensitized PPC1 cells to TRAIL-induced apoptosis. Together these results suggest that PCTAIRE1 contributes to the resistance of cancer cell lines to apoptosis induced by TNF-family cytokines, which implies that PCTAIRE1 inhibitors could have synergistic effects with TNF-family cytokines for cytodestruction of cancer cells.

  4. Silencing of Taxol-Sensitizer Genes in Cancer Cells: Lack of Sensitization Effects

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Shang-Lang [Department of Biochemistry and Molecular Biology, College of Medicine, Chang Gung University, Taoyuan 333, Taiwan (China); Chao, Chuck C.-K., E-mail: cckchao@mail.cgu.edu.tw [Department of Biochemistry and Molecular Biology, College of Medicine, Chang Gung University, Taoyuan 333, Taiwan (China); Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan 333, Taiwan (China); Department of Medical Research and Development, Chang Gung Memorial Hospital, Taoyuan 333, Taiwan (China)

    2015-06-16

    A previous genome-wide screening analysis identified a panel of genes that sensitize the human non-small-cell lung carcinoma cell line NCI-H1155 to taxol. However, whether the identified genes sensitize other cancer cells to taxol has not been examined. Here, we silenced the taxol-sensitizer genes identified (acrbp, atp6v0d2, fgd4, hs6st2, psma6, and tubgcp2) in nine other cancer cell types (including lung, cervical, ovarian, and hepatocellular carcinoma cell lines) that showed reduced cell viability in the presence of a sub-lethal concentration of taxol. Surprisingly, none of the genes studied increased sensitivity to taxol in the tested panel of cell lines. As observed in H1155 cells, SKOV3 cells displayed induction of five of the six genes studied in response to a cell killing dose of taxol. The other cell types were much less responsive to taxol. Notably, four of the five inducible taxol-sensitizer genes tested (acrbp, atp6v0d2, psma6, and tubgcp2) were upregulated in a taxol-resistant ovarian cancer cell line. These results indicate that the previously identified taxol-sensitizer loci are not conserved genetic targets involved in inhibiting cell proliferation in response to taxol. Our findings also suggest that regulation of taxol-sensitizer genes by taxol may be critical for acquired cell resistance to the drug.

  5. Trastuzumab Sensitizes Ovarian Cancer Cells to EGFR-targeted Therapeutics

    Directory of Open Access Journals (Sweden)

    Wilken Jason A

    2010-03-01

    Full Text Available Abstract Background Early studies have demonstrated comparable levels of HER2/ErbB2 expression in both breast and ovarian cancer. Trastuzumab (Herceptin, a therapeutic monoclonal antibody directed against HER2, is FDA-approved for the treatment of both early and late stage breast cancer. However, clinical studies of trastuzumab in epithelial ovarian cancer (EOC patients have not met the same level of success. Surprisingly, however, no reports have examined either the basis for primary trastuzumab resistance in ovarian cancer or potential ways of salvaging trastuzumab as a potential ovarian cancer therapeutic. Methods An in vitro model of primary trastuzumab-resistant ovarian cancer was created by long-term culture of HER2-positive ovarian carcinoma-derived cell lines with trastuzumab. Trastuzumab treated vs. untreated parental cells were compared for HER receptor expression, trastuzumab sensitivity, and sensitivity to other HER-targeted therapeutics. Results In contrast to widely held assumptions, here we show that ovarian cancer cells that are not growth inhibited by trastuzumab are still responsive to trastuzumab. Specifically, we show that responsiveness to alternative HER-targeted inhibitors, such as gefitinib and cetuximab, is dramatically potentiated by long-term trastuzumab treatment of ovarian cancer cells. HER2-positive ovarian carcinoma-derived cells are, therefore, not "unresponsive" to trastuzumab as previously assumed, even when they not growth inhibited by this drug. Conclusions Given the recent success of EGFR-targeted therapeutics for the treatment of other solid tumors, and the well-established safety profile of trastuzumab, results presented here provide a rationale for re-evaluation of trastuzumab as an experimental ovarian cancer therapeutic, either in concert with, or perhaps as a "primer" for EGFR-targeted therapeutics.

  6. Glucose-deprivation increases thyroid cancer cells sensitivity to metformin.

    Science.gov (United States)

    Bikas, Athanasios; Jensen, Kirk; Patel, Aneeta; Costello, John; McDaniel, Dennis; Klubo-Gwiezdzinska, Joanna; Larin, Olexander; Hoperia, Victoria; Burman, Kenneth D; Boyle, Lisa; Wartofsky, Leonard; Vasko, Vasyl

    2015-12-01

    Metformin inhibits thyroid cancer cell growth. We sought to determine if variable glucose concentrations in medium alter the anti-cancer efficacy of metformin. Thyroid cancer cells (FTC133 and BCPAP) were cultured in high-glucose (20 mM) and low-glucose (5 mM) medium before treatment with metformin. Cell viability and apoptosis assays were performed. Expression of glycolytic genes was examined by real-time PCR, western blot, and immunostaining. Metformin inhibited cellular proliferation in high-glucose medium and induced cell death in low-glucose medium. In low-, but not in high-glucose medium, metformin induced endoplasmic reticulum stress, autophagy, and oncosis. At micromolar concentrations, metformin induced phosphorylation of AMP-activated protein kinase and blocked p-pS6 in low-glucose medium. Metformin increased the rate of glucose consumption from the medium and prompted medium acidification. Medium supplementation with glucose reversed metformin-inducible morphological changes. Treatment with an inhibitor of glycolysis (2-deoxy-d-glucose (2-DG)) increased thyroid cancer cell sensitivity to metformin. The combination of 2-DG with metformin led to cell death. Thyroid cancer cell lines were characterized by over-expression of glycolytic genes, and metformin decreased the protein level of pyruvate kinase muscle 2 (PKM2). PKM2 expression was detected in recurrent thyroid cancer tissue samples. In conclusion, we have demonstrated that the glucose concentration in the cellular milieu is a factor modulating metformin's anti-cancer activity. These data suggest that the combination of metformin with inhibitors of glycolysis could represent a new strategy for the treatment of thyroid cancer.

  7. EPS8 inhibition increases cisplatin sensitivity in lung cancer cells.

    Directory of Open Access Journals (Sweden)

    Lidija K Gorsic

    Full Text Available Cisplatin, a commonly used chemotherapeutic, is associated with ototoxicity, renal toxicity and neurotoxicity, thus identifying means to increase the therapeutic index of cisplatin may allow for improved outcomes. A SNP (rs4343077 within EPS8, discovered through a genome wide association study of cisplatin-induced cytotoxicity and apoptosis in lymphoblastoid cell lines (LCLs, provided impetus to further study this gene. The purpose of this work was to evaluate the role of EPS8 in cellular susceptibility to cisplatin in cancerous and non-cancerous cells. We used EPS8 RNA interference to determine the effect of decreased EPS8 expression on LCL and A549 lung cancer cell sensitivity to cisplatin. EPS8 knockdown in LCLs resulted in a 7.9% increase in cisplatin-induced survival (P = 1.98 × 10(-7 and an 8.7% decrease in apoptosis (P = 0.004 compared to control. In contrast, reduced EPS8 expression in lung cancer cells resulted in a 20.6% decrease in cisplatin-induced survival (P = 5.08 × 10(-5. We then investigated an EPS8 inhibitor, mithramycin A, as a potential agent to increase the therapeutic index of cisplatin. Mithramycin A decreased EPS8 expression in LCLs resulting in decreased cellular sensitivity to cisplatin as evidenced by lower caspase 3/7 activation following cisplatin treatment (42.7% ± 6.8% relative to control P = 0.0002. In 5 non-small-cell lung carcinoma (NSCLC cell lines, mithramycin A also resulted in decreased EPS8 expression. Adding mithramycin to 4 NSCLC cell lines and a bladder cancer cell line, resulted in increased sensitivity to cisplatin that was significantly more pronounced in tumor cell lines than in LCL lines (p<0.0001. An EGFR mutant NSCLC cell line (H1975 showed no significant change in sensitivity to cisplatin with the addition of mithramycin treatment. Therefore, an inhibitor of EPS8, such as mithramycin A, could improve cisplatin treatment by increasing sensitivity of tumor relative to normal cells.

  8. Propranolol sensitizes thyroid cancer cells to cytotoxic effect of vemurafenib.

    Science.gov (United States)

    Wei, Wei-Jun; Shen, Chen-Tian; Song, Hong-Jun; Qiu, Zhong-Ling; Luo, Quan-Yong

    2016-09-01

    Treatment options for advanced metastatic or progressive thyroid cancers are limited. Although targeted therapy specifically inhibiting intracellular kinase signaling pathways has markedly changed the therapeutic landscape, side-effects and resistance of single agent targeted therapy often leads to termination of the treatment. The objective of the present study was to identify the antitumor property of the non-selective β-adrenergic receptor antagonist propranolol for thyroid cancers. Human thyroid cancer cell lines 8505C, K1, BCPAP and BHP27 were used in the present study. Broad β-blocker propranolol and β2-specific antagonist ICI118551, but not β1-specific antagonist atenolol, inhibited the growth of 8505C and K1 cells. Propranolol treatment inhibited growth and induced apoptosis of 8505C cells in vitro and in vivo, which are closely associated with decreased expressions of cyclin D1 and anti-apoptotic Bcl-2. Expression of hexokinase 2 (HK2) and glucose transporter 1 (GLUT1) also decreased following propranolol intervention. 18F-FDG PET/CT imaging of the 8505C xenografts validated shrinkage of the tumors in the propranolol-treated group when compared to the phosphate‑buffered saline treated group. Finally, we found that propranolol can amplify the cytotoxicity of vemurafenib and sensitize thyroid cancer cells to cytotoxic effect of vemurafenib. Our present results suggest that propranolol has potential activity against thyroid cancers and investigation of the combination with targeted molecular therapy for progressive thyroid cancers could be beneficial.

  9. Syrosingopine sensitizes cancer cells to killing by metformin

    Science.gov (United States)

    Benjamin, Don; Colombi, Marco; Hindupur, Sravanth K.; Betz, Charles; Lane, Heidi A.; El-Shemerly, Mahmoud Y. M.; Lu, Min; Quagliata, Luca; Terracciano, Luigi; Moes, Suzette; Sharpe, Timothy; Wodnar-Filipowicz, Aleksandra; Moroni, Christoph; Hall, Michael N.

    2016-01-01

    We report that the anticancer activity of the widely used diabetic drug metformin is strongly potentiated by syrosingopine. Synthetic lethality elicited by combining the two drugs is synergistic and specific to transformed cells. This effect is unrelated to syrosingopine’s known role as an inhibitor of the vesicular monoamine transporters. Syrosingopine binds to the glycolytic enzyme α-enolase in vitro, and the expression of the γ-enolase isoform correlates with nonresponsiveness to the drug combination. Syrosingopine sensitized cancer cells to metformin and its more potent derivative phenformin far below the individual toxic threshold of each compound. Thus, combining syrosingopine and codrugs is a promising therapeutic strategy for clinical application for the treatment of cancer. PMID:28028542

  10. Identification of transporters associated with Etoposide sensitivity of stomach cancer cell lines and methotrexate sensitivity of breast cancer cell lines by quantitative targeted absolute proteomics.

    Science.gov (United States)

    Obuchi, Wataru; Ohtsuki, Sumio; Uchida, Yasuo; Ohmine, Ken; Yamori, Takao; Terasaki, Tetsuya

    2013-02-01

    Membrane transporter proteins may influence the sensitivity of cancer cells to anticancer drugs that can be recognized as substrates. The purpose of this study was to identify proteins that play a key role in the drug sensitivity of stomach and breast cancer cell lines by measuring the absolute protein expression levels of multiple transporters and other membrane proteins and examining their correlation to drug sensitivity. Absolute protein expression levels of 90 membrane proteins were examined by quantitative targeted absolute proteomics using liquid chromatography-linked tandem mass spectrometry. Among them, 11 and 14 membrane proteins, including transporters, were present in quantifiable amounts in membrane fraction of stomach cancer and breast cancer cell lines, respectively. In stomach cancer cell lines, the protein expression level of multidrug resistance-associated protein 1 (MRP1) was inversely correlated with etoposide sensitivity. MK571, an MRP inhibitor, increased both the cell-to-medium ratio of etoposide and the etoposide sensitivity of MRP1-expressing stomach cancer cell lines. In breast cancer cell lines, the protein expression level of reduced folate carrier 1 (RFC1) was directly correlated with methotrexate (MTX) sensitivity. Initial uptake rate and steady-state cell-to-medium ratio of [(3)H]MTX were correlated with both RFC1 expression level and MTX sensitivity. These results suggest that MRP1 modulates the etoposide sensitivity of stomach cancer cell lines and RFC1 modulates the MTX sensitivity of breast cancer cell lines. Our results indicate that absolute quantification of multiple membrane proteins could be a useful strategy for identification of candidate proteins involved in drug sensitivity.

  11. Breast cancer cells with acquired antiestrogen resistance are sensitized to cisplatin-induced cell death

    DEFF Research Database (Denmark)

    Yde, Christina Westmose; Gyrd-Hansen, Mads; Lykkesfeldt, Anne E

    2007-01-01

    for future breast cancer treatment. In this study, we have investigated the effect of the chemotherapeutic compound cisplatin using a panel of antiestrogen-resistant breast cancer cell lines established from the human breast cancer cell line MCF-7. We show that the antiestrogen-resistant cells...... with parental MCF-7 cells. Our data show that Bcl-2 can protect antiestrogen-resistant breast cancer cells from cisplatin-induced cell death, indicating that the reduced expression of Bcl-2 in the antiestrogen-resistant cells plays a role in sensitizing the cells to cisplatin treatment.......Antiestrogens are currently used for treating breast cancer patients who have estrogen receptor-positive tumors. However, patients with advanced disease will eventually develop resistance to the drugs. Therefore, compounds effective on antiestrogen-resistant tumors will be of great importance...

  12. KRAS Genomic Status Predicts the Sensitivity of Ovarian Cancer Cells to Decitabine | Office of Cancer Genomics

    Science.gov (United States)

    Decitabine, a cancer therapeutic that inhibits DNA methylation, produces variable antitumor response rates in patients with solid tumors that might be leveraged clinically with identification of a predictive biomarker. In this study, we profiled the response of human ovarian, melanoma, and breast cancer cells treated with decitabine, finding that RAS/MEK/ERK pathway activation and DNMT1 expression correlated with cytotoxic activity. Further, we showed that KRAS genomic status predicted decitabine sensitivity in low-grade and high-grade serous ovarian cancer cells.

  13. Resveratrol Sensitizes Selectively Thyroid Cancer Cell to 131-Iodine Toxicity

    Directory of Open Access Journals (Sweden)

    Seyed Jalal Hosseinimehr

    2014-01-01

    Full Text Available Background. In this study, the radiosensitizing effect of resveratrol as a natural product was investigated on cell toxicity induced by 131I in thyroid cancer cell. Methods. Human thyroid cancer cell and human nonmalignant fibroblast cell (HFFF2 were treated with 131I and/or resveratrol at different concentrations for 48 h. The cell proliferation was measured by determination of the percent of the survival cells using 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide (MTT assay. Results. Findings of this study show that resveratrol enhanced the cell death induced by 131I on thyroid cancer cell. Also, resveratrol exhibited a protective effect on normal cells against 131I toxicity. Conclusion. This result indicates a promising effect of resveratrol on improvement of cellular toxicity during iodine therapy.

  14. IL-35 over-expression increases apoptosis sensitivity and suppresses cell growth in human cancer cells.

    Science.gov (United States)

    Long, Jun; Zhang, Xulong; Wen, Mingjie; Kong, Qingli; Lv, Zhe; An, Yunqing; Wei, Xiao-Qing

    2013-01-01

    Interleukin (IL)-35 is a novel heterodimeric cytokine in the IL-12 family and is composed of two subunits: Epstein-Barr virus-induced gene 3 (EBI3) and IL-12p35. IL-35 is expressed in T regulatory (Treg) cells and contributes to the immune suppression function of these cells. In contrast, we found that both IL-35 subunits were expressed concurrently in most human cancer cell lines compared to normal cell lines. In addition, we found that TNF-α and IFN-γ stimulation led to increased IL-35 expression in human cancer cells. Furthermore, over-expression of IL-35 in human cancer cells suppressed cell growth in vitro, induced cell cycle arrest at the G1 phase, and mediated robust apoptosis induced by serum starvation, TNF-α, and IFN-γ stimulation through the up-regulation of Fas and concurrent down-regulation of cyclinD1, survivin, and Bcl-2 expression. In conclusion, our results reveal a novel functional role for IL-35 in suppressing cancer activity, inhibiting cancer cell growth, and increasing the apoptosis sensitivity of human cancer cells through the regulation of genes related to the cell cycle and apoptosis. Thus, this research provides new insights into IL-35 function and presents a possible target for the development of novel cancer therapies.

  15. Losartan sensitizes selectively prostate cancer cell to ionizing radiation.

    Science.gov (United States)

    Yazdannejat, H; Hosseinimehr, S J; Ghasemi, A; Pourfallah, T A; Rafiei, A

    2016-01-11

    Losartan is an angiotensin II receptor (AT-II-R) blocker that is widely used by human for blood pressure regulation. Also, it has antitumor property. In this study, we investigated the radiosensitizing effect of losartan on cellular toxicity induced by ionizing radiation on prostate cancer and non-malignant fibroblast cells. Human prostate cancer (DU-145) and human non-malignant fibroblast cells (HFFF2) were treated with losartan at different concentrations (0.5, 1, 10, 50 and 100 µM) and then these cells were exposed to ionizing radiation. The cell proliferation was determined using MTT assay. Our results showed that losartan exhibited antitumor effect on prostate cancer cells; it was reduced cell survival to 66% at concentration 1 µM. Losartan showed an additive killing effect in combination with ionizing radiation on prostate cancer cell. The cell proliferation was reduced to 54% in the prostate cancer cells treated with losartan at concentration 1 µM in combination with ionizing radiation. Losartan did not exhibit any toxicity on HFFF2 cell. This result shows a promising effect of losartan on enhancement of therapeutic effect of ionizing radiation in patients during therapy.

  16. Sensitizing cancer cells to TRAIL-induced death by micellar delivery of mitoxantrone.

    Science.gov (United States)

    Grandhi, Taraka Sai Pavan; Potta, Thrimoorthy; Taylor, David J; Tian, Yanqing; Johnson, Roger H; Meldrum, Deirdre R; Rege, Kaushal

    2014-01-01

    TNFα-related apoptosis-inducing ligand (TRAIL) induces death selectively in cancer cells. However, subpopulations of cancer cells are either resistant to or can develop resistance to TRAIL-induced death. As a result, strategies that overcome this resistance are currently under investigation. We have recently identified several US FDA-approved drugs with TRAIL-sensitization activity against prostate, breast and pancreatic cancer cells. Mitoxantrone, a previously unknown TRAIL sensitizer identified in the screen, was successfully encapsulated in methoxy-, amine- and carboxyl-terminated PEG-DSPE micelles in order to facilitate delivery of the drug to cancer cells. All three micelle types were extensively characterized for their physicochemical properties and evaluated for their ability to sensitize cancer cells to TRAIL-induced death. Our results indicate that micelle-encapsulated mitoxantrone can be advantageously employed in synergistic treatments with TRAIL, leading to a biocompatible delivery system and amplified cell killing activity for combination chemotherapeutic cancer treatments.

  17. Co-treatment of Salinomycin Sensitizes AZD5363-treated Cancer Cells Through Increased Apoptosis.

    Science.gov (United States)

    Choi, Ae-Ran; Jung, Myung-Ji; Kim, Ju-Hwa; Yoon, Sungpil

    2015-09-01

    AZD5363, an inhibitor of protein kinase B (AKT), is currently in clinical trials assessing the potential of the phosphoinositide 3-kinase (PI3K)/AKT/mammalian target of rapamycin (mTOR) pathway. The purpose of the present study was to identify conditions that increase the sensitivity of cancer cells to AZD5363. Microscopic examination revealed that treatment of cancer cells with a low concentration of salinomycin reduced cellular growth of AZD5363-treated breast cancer cells. Furthermore, fluorescence-activated cell sorting (FACS) analysis, Hoechst staining, and annexin V staining revealed that co-treatment with salinomycin sensitizes AZD5363-treated cancer cells via increased apoptosis with S-phase arrest. These results suggest that salinomycin can be applied to increase treatment efficacy for AZD5363-treated cancer cells. Our findings may contribute to improving the efficacy of the development of AZD5363-based sensitization therapies for patients with cancer.

  18. Collateral sensitivity to cisplatin in KB-8-5-11 drug-resistant cancer cells.

    LENUS (Irish Health Repository)

    Doherty, Ben

    2014-01-01

    KB-8-5-11 cells are a drug-resistant cervical cell model that overexpresses ABCB1 (P-glycoprotein). KB-8-5-11 has become sensitive to non-ABCB1 substrate cisplatin. Understanding the mechanism of collateral sensitivity to cisplatin may lead to biomarker discovery for platinum sensitivity in patients with cancer.

  19. Curcumin induces chemo/radio-sensitization in ovarian cancer cells and curcumin nanoparticles inhibit ovarian cancer cell growth

    Directory of Open Access Journals (Sweden)

    Yallapu Murali M

    2010-04-01

    Full Text Available Abstract Background Chemo/radio-resistance is a major obstacle in treating advanced ovarian cancer. The efficacy of current treatments may be improved by increasing the sensitivity of cancer cells to chemo/radiation therapies. Curcumin is a naturally occurring compound with anti-cancer activity in multiple cancers; however, its chemo/radio-sensitizing potential is not well studied in ovarian cancer. Herein, we demonstrate the effectiveness of a curcumin pre-treatment strategy for chemo/radio-sensitizing cisplatin resistant ovarian cancer cells. To improve the efficacy and specificity of curcumin induced chemo/radio sensitization, we developed a curcumin nanoparticle formulation conjugated with a monoclonal antibody specific for cancer cells. Methods Cisplatin resistant A2780CP ovarian cancer cells were pre-treated with curcumin followed by exposure to cisplatin or radiation and the effect on cell growth was determined by MTS and colony formation assays. The effect of curcumin pre-treatment on the expression of apoptosis related proteins and β-catenin was determined by Western blotting or Flow Cytometry. A luciferase reporter assay was used to determine the effect of curcumin on β-catenin transcription activity. The poly(lactic acid-co-glycolic acid (PLGA nanoparticle formulation of curcumin (Nano-CUR was developed by a modified nano-precipitation method and physico-chemical characterization was performed by transmission electron microscopy and dynamic light scattering methods. Results Curcumin pre-treatment considerably reduced the dose of cisplatin and radiation required to inhibit the growth of cisplatin resistant ovarian cancer cells. During the 6 hr pre-treatment, curcumin down regulated the expression of Bcl-XL and Mcl-1 pro-survival proteins. Curcumin pre-treatment followed by exposure to low doses of cisplatin increased apoptosis as indicated by annexin V staining and cleavage of caspase 9 and PARP. Additionally, curcumin pre

  20. Study of gemcitabine-sensitive/resistant cancer cells by cell cloning and synchrotron FTIR microspectroscopy.

    Science.gov (United States)

    Rutter, Abigail V; Siddique, Muhammad R; Filik, Jacob; Sandt, Christophe; Dumas, Paul; Cinque, Gianfelice; Sockalingum, Ganesh D; Yang, Ying; Sulé-Suso, Josep

    2014-08-01

    Over the last few years, significant scientific insight on the effects of chemotherapy drugs at cellular level using synchrotron-based FTIR (S-FTIR) microspectroscopy has been obtained. The work carried out so far has identified spectral differences in cancer cells before and after the addition of drugs. However, this had to account for the following issues. First, chemotherapy agents cause both chemical and morphological changes in cells, the latter being responsible for changes in the spectral profile not correlated with biochemical characteristics. Second, as the work has been carried out in mixed populations of cells (resistant and sensitive), it is important to distinguish the spectral differences which are due to sensitivity/resistance to those due to cell morphology and/or cell mixture. Here, we successfully cloned resistant and sensitive lung cancer cells to a chemotherapy drug. This allowed us to study a more uniform population and, more important, allowed us to study sensitive and resistant cells prior to the addition of the drug with S-FTIR microscopy. Principal component analysis (PCA) did not detect major differences in resistant cells prior to and after adding the drug. However, PCA separated sensitive cells prior to and after the addition of the drug. This would indicate that the spectral differences between cells prior to and after adding a drug might reside on those more or less sensitive cells that have been able to remain alive when they were collected to be studied with S-FTIR microspectroscopy. This is a proof of concept and a feasibility study showing a methodology that opens a new way to identify the effects of drugs on more homogeneous cell populations using vibrational spectroscopy.

  1. REV3L modulates cisplatin sensitivity of non-small cell lung cancer H1299 cells.

    Science.gov (United States)

    Wang, Wenjie; Sheng, Wenjiong; Yu, Chenxiao; Cao, Jianping; Zhou, Jundong; Wu, Jinchang; Zhang, Huojun; Zhang, Shuyu

    2015-09-01

    Lung cancer remains the leading cause of cancer-related mortality worldwide and non-small cell lung cancer (NSCLC) accounts for approximately 80-85% of all cases of lung cancer. Cisplatin plays a significant role in the management of human lung cancer. Translesion DNA synthesis (TLS) is involved in DNA damage repair. DNA polymerase ζ (Pol ζ) is able to mediate the DNA replication bypass of DNA damage, which is suggested to be involved in chemoresistance. REV3L is the catalytic subunit of Pol ζ. Due to its critical role in translesion DNA synthesis, whether REV3L modulates cisplatin response in NSCLC cells remains unknown. In this study, REV3L overexpression and silencing H1299 cell lines were established. The reports showed that cisplatin induced the expression of REV3L by recruiting Sp1 to its promoter. Similar results were obtained when the ability of the cells to express luciferase from a platinated plasmid was measured. Co-transfection of the reporter with the REV3L overexpression vector or REV3L plus REV7L significantly enhanced the reporter activity. Nuclear condensation and fragmentation of shRNA-REV3L H1299 cells were more pronounced than shRNA-NC H1299 cells after cisplatin exposure, indicating that REV3L overexpression abolished cisplatin-induced DNA damage. Moreover, a forced expression of REV3L conferred the resistance of H1299 cells to cisplatin, whereas the knockdown of REV3L sensitized cisplatin efficacy in H1299 cells. Taken together, we demonstrated that inhibition of REV3L sensitized lung cancer H1299 cells to cisplatin treatment. Thus, REV3L may be a novel target for the chemotherapy of NSCLC.

  2. Signatures of Drug Sensitivity in Nonsmall Cell Lung Cancer

    Directory of Open Access Journals (Sweden)

    Hua C. Gong

    2011-01-01

    Full Text Available We profiled receptor tyrosine kinase pathway activation and key gene mutations in eight human lung tumor cell lines and 50 human lung tumor tissue samples to define molecular pathways. A panel of eight kinase inhibitors was used to determine whether blocking pathway activation affected the tumor cell growth. The HER1 pathway in HER1 mutant cell lines HCC827 and H1975 were found to be highly activated and sensitive to HER1 inhibition. H1993 is a c-MET amplified cell line showing c-MET and HER1 pathway activation and responsiveness to c-MET inhibitor treatment. IGF-1R pathway activated H358 and A549 cells are sensitive to IGF-1R inhibition. The downstream PI3K inhibitor, BEZ-235, effectively inhibited tumor cell growth in most of the cell lines tested, except the H1993 and H1650 cells, while the MEK inhibitor PD-325901 was effective in blocking the growth of KRAS mutated cell line H1734 but not H358, A549 and H460. Hierarchical clustering of primary tumor samples with the corresponding tumor cell lines based on their pathway signatures revealed similar profiles for HER1, c-MET and IGF-1R pathway activation and predict potential treatment options for the primary tumors based on the tumor cell lines response to the panel of kinase inhibitors.

  3. Mortalin sensitizes human cancer cells to MKT-077-induced senescence.

    Science.gov (United States)

    Deocaris, Custer C; Widodo, Nashi; Shrestha, Bhupal G; Kaur, Kamaljit; Ohtaka, Manami; Yamasaki, Kazuhiko; Kaul, Sunil C; Wadhwa, Renu

    2007-07-18

    Mortalin is a chaperone protein that functions in many cellular processes such as mitochondrial biogenesis, intracellular trafficking, cell proliferation and signaling. Its upregulation in many human cancers makes it a candidate target for therapeutic intervention by small molecule drugs. In continuation to our earlier studies showing mortalin as a cellular target of MKT-077, a mitochondrion-seeking delocalized cationic dye that causes selective death of cancer cells, in this work, we report that MKT-077 binds to the nucleotide-binding domain of mortalin, causes tertiary structural changes in the protein, inactivates its chaperone function, and induces senescence in human tumor cell lines. Interestingly, in tumor cells with elevated level of mortalin expression, fairly low drug doses were sufficient to induce senescence. Guided by molecular screening for mortalin in tumor cells, our results led to the idea that working at low doses of the drug could be an alternative senescence-inducing cancer therapeutic strategy that could, in theory, avoid renal toxicities responsible for the abortion of MKT-077 clinical trials. Our work may likely translate to a re-appraisal of the therapeutic benefits of low doses of several classes of anti-tumor drugs, even of those that had been discontinued due to adverse effects.

  4. Epicatechin stimulates mitochondrial activity and selectively sensitizes cancer cells to radiation.

    Directory of Open Access Journals (Sweden)

    Hosam A Elbaz

    Full Text Available Radiotherapy is the treatment of choice for solid tumors including pancreatic cancer, but the effectiveness of treatment is limited by radiation resistance. Resistance to chemotherapy or radiotherapy is associated with reduced mitochondrial respiration and drugs that stimulate mitochondrial respiration may decrease radiation resistance. The objectives of this study were to evaluate the potential of (--epicatechin to stimulate mitochondrial respiration in cancer cells and to selectively sensitize cancer cells to radiation. We investigated the natural compound (--epicatechin for effects on mitochondrial respiration and radiation resistance of pancreatic and glioblastoma cancer cells using a Clark type oxygen electrode, clonogenic survival assays, and Western blot analyses. (--Epicatechin stimulated mitochondrial respiration and oxygen consumption in Panc-1 cells. Human normal fibroblasts were not affected. (--Epicatechin sensitized Panc-1, U87, and MIA PaCa-2 cells with an average radiation enhancement factor (REF of 1.7, 1.5, and 1.2, respectively. (--Epicatechin did not sensitize normal fibroblast cells to ionizing radiation with a REF of 0.9, suggesting cancer cell selectivity. (--Epicatechin enhanced Chk2 phosphorylation and p21 induction when combined with radiation in cancer, but not normal, cells. Taken together, (--epicatechin radiosensitized cancer cells, but not normal cells, and may be a promising candidate for pancreatic cancer treatment when combined with radiation.

  5. Establishment of a drug sensitivity panel using human lung cancer cell lines.

    Directory of Open Access Journals (Sweden)

    Matsushita A

    1999-04-01

    Full Text Available We established a drug sensitivity panel consisting of 24 human lung cancer cell lines. Using this panel, we evaluated 26 anti-cancer agents: three alkylators, three platinum compounds, four antimetabolites, one topoisomerase I inhibitor, five topoisomerase II inhibitors, seven antimitotic agents and three tyrosine kinase inhibitors. This panel showed the following: a Drug sensitivity patterns reflected their clinically-established patterns of action. For example, doxorubicin and etoposide were shown to be active against small cell lung cancer cell lines and mitomycin-C and 5-fluorouracil were active against non-small cell lung cancer cell lines, in agreement with clinical data. b Correlation analysis of the mean graphs derived from the logarithm of IC50 values of the drugs gave insight into the mechanism of each drug's action. Thus, two drug combinations with reverse or no correlation, such as the combination of cisplatin and vinorelbine, might be good candidates for the ideal two drug combination in the treatment of lung cancer, as is being confirmed in clinical trials. c Using cluster analysis of the cell lines in the panel with their drug sensitivity patterns, we could classify the cell lines into four groups depending on the drug sensitivity similarity. This classification will be useful to elucidate the cellular mechanism of action and drug resistance. Thus, our drug sensitivity panel will be helpful to explore new drugs or to develop a new combination of anti-cancer agents for the treatment of lung cancer.

  6. ATM-Deficient Colorectal Cancer Cells Are Sensitive to the PARP Inhibitor Olaparib.

    Science.gov (United States)

    Wang, Chen; Jette, Nicholas; Moussienko, Daniel; Bebb, D Gwyn; Lees-Miller, Susan P

    2017-02-06

    The ataxia telangiectasia mutated (ATM) protein kinase plays a central role in the cellular response to DNA damage. Loss or inactivation of both copies of the ATM gene (ATM) leads to ataxia telangiectasia, a devastating childhood condition characterized by neurodegeneration, immune deficiencies, and cancer predisposition. ATM is also absent in approximately 40% of mantle cell lymphomas (MCLs), and we previously showed that MCL cell lines with loss of ATM are sensitive to poly-ADP ribose polymerase (PARP) inhibitors. Next-generation sequencing of patient tumors has revealed that ATM is altered in many human cancers including colorectal, lung, prostate, and breast. Here, we show that the colorectal cancer cell line SK-CO-1 lacks detectable ATM protein expression and is sensitive to the PARP inhibitor olaparib. Similarly, HCT116 colorectal cancer cells with shRNA depletion of ATM are sensitive to olaparib, and depletion of p53 enhances this sensitivity. Moreover, HCT116 cells are sensitive to olaparib in combination with the ATM inhibitor KU55933, and sensitivity is enhanced by deletion of p53. Together our studies suggest that PARP inhibitors may have potential for treating colorectal cancer with ATM dysfunction and/or colorectal cancer with mutation of p53 when combined with an ATM kinase inhibitor.

  7. Metabolic determinants of cancer cell sensitivity to glucose limitation and biguanides

    Science.gov (United States)

    Birsoy, Kıvanç; Possemato, Richard; Lorbeer, Franziska K.; Bayraktar, Erol C.; Thiru, Prathapan; Yucel, Burcu; Wang, Tim; Chen, Walter W.; Clish, Clary B.; Sabatini, David M.

    2014-04-01

    As the concentrations of highly consumed nutrients, particularly glucose, are generally lower in tumours than in normal tissues, cancer cells must adapt their metabolism to the tumour microenvironment. A better understanding of these adaptations might reveal cancer cell liabilities that can be exploited for therapeutic benefit. Here we developed a continuous-flow culture apparatus (Nutrostat) for maintaining proliferating cells in low-nutrient media for long periods of time, and used it to undertake competitive proliferation assays on a pooled collection of barcoded cancer cell lines cultured in low-glucose conditions. Sensitivity to low glucose varies amongst cell lines, and an RNA interference (RNAi) screen pinpointed mitochondrial oxidative phosphorylation (OXPHOS) as the major pathway required for optimal proliferation in low glucose. We found that cell lines most sensitive to low glucose are defective in the OXPHOS upregulation that is normally caused by glucose limitation as a result of either mitochondrial DNA (mtDNA) mutations in complex I genes or impaired glucose utilization. These defects predict sensitivity to biguanides, antidiabetic drugs that inhibit OXPHOS, when cancer cells are grown in low glucose or as tumour xenografts. Notably, the biguanide sensitivity of cancer cells with mtDNA mutations was reversed by ectopic expression of yeast NDI1, a ubiquinone oxidoreductase that allows bypass of complex I function. Thus, we conclude that mtDNA mutations and impaired glucose utilization are potential biomarkers for identifying tumours with increased sensitivity to OXPHOS inhibitors.

  8. Effects of bortezomib in sensitizing human prostate cancer cell lines to NK-mediated cytotoxicity

    Institute of Scientific and Technical Information of China (English)

    Wei Hu; Rui-Rui Zheng; Hui-Xia Cui; Dan Yue; Yong Wang; You-Hong Jiang

    2012-01-01

    The proteasome inhibitor,bortezomib,has been demonstrated to sensitize tumor cells to tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-mediated apoptosis.Natural killer (NK) cells represent potent antitumor effector cells.They also express TRAIL.Therefore.we investigated whether bortezomib could sensitize tumor cells to NK cell-mediated killing,and have the same effect in human prostate cancer cell lines (LNCaP and DU145).We found that bortezomib strongly inhibits proliferation in both cell lines.Furthermore,compared with LNCaP cells,DU 145 cells are more sensitive to bortezomib-induced apoptosis.However,bortezomib is unable to sensitize these two cell lines to NK cell-mediated killing in short-term assays.In long-term assays,we found that killing mediated by activated NK cells following bortezornib treatment leads to greater antitumor effects than either treatment alone.In addition,treatment with bortezomib causes these cells to upregulate apoptosis-related mRNA as well as death receptors and downregulate the major histocompatibility class (MHC)-Ⅰ molecule on the cell surface of DU145 cells.In contrast,LNCaP cells are not sensitized by this treatment.Death receptors and the MHC-Ⅰ molecule did not change in this cell line.These-data suggest that bortezomib can be used to sensitize prostate cancer cells to NK cell-mediated killing and improve current cancer therapies.This therapeutic strategy may be more effective in patients with androgen-insensitive prostate cancer.

  9. Alpinetin inhibits lung cancer progression and elevates sensitization drug-resistant lung cancer cells to cis-diammined dichloridoplatium

    Directory of Open Access Journals (Sweden)

    Wu L

    2015-11-01

    Full Text Available Lin Wu, Wei Yang, Su-ning Zhang, Ji-bin Lu Department of Thoracic Surgery, Sheng Jing Hospital of China Medical University, Shenyang, People’s Republic of China Objective: Alpinetin is a novel flavonoid that has demonstrated potent antitumor activity in previous studies. However, the efficacy and mechanism of alpinetin in treating lung cancer have not been determined. Methods: We evaluated the impact of different doses and durations of alpinetin treatment on the cell proliferation, the apoptosis of lung cancer cells, as well as the drug-resistant lung cancer cells. Results: This study showed that the alpinetin inhibited the cell proliferation, enhanced the apoptosis, and inhibited the PI3K/Akt signaling in lung cancer cells. Moreover, alpinetin significantly increased the sensitivity of drug-resistant lung cancer cells to the chemotherapeutic effect of cis-diammined dichloridoplatium. Taken together, this study demonstrated that alpinetin significantly suppressed the development of human lung cancer possibly by influencing mitochondria and the PI3K/Akt signaling pathway and sensitized drug-resistant lung cancer cells. Conclusion: Alpinetin may be used as a potential compound for combinatorial therapy or as a complement to other chemotherapeutic agents when multiple lines of treatments have failed to reduce lung cancer. Keywords: alpinetin, cell proliferation and apoptosis, drug resistance reversal, PI3K/Akt, lung cancer

  10. Identification of a panel of sensitive and specific DNA methylation markers for squamous cell lung cancer

    Directory of Open Access Journals (Sweden)

    Laird Peter W

    2008-07-01

    Full Text Available Abstract Background Lung cancer is the leading cause of cancer death in men and women in the United States and Western Europe. Over 160,000 Americans die of this disease every year. The five-year survival rate is 15% – significantly lower than that of other major cancers. Early detection is a key factor in increasing lung cancer patient survival. DNA hypermethylation is recognized as an important mechanism for tumor suppressor gene inactivation in cancer and could yield powerful biomarkers for early detection of lung cancer. Here we focused on developing DNA methylation markers for squamous cell carcinoma of the lung. Using the sensitive, high-throughput DNA methylation analysis technique MethyLight, we examined the methylation profile of 42 loci in a collection of 45 squamous cell lung cancer samples and adjacent non-tumor lung tissues from the same patients. Results We identified 22 loci showing significantly higher DNA methylation levels in tumor tissue than adjacent non-tumor lung. Of these, eight showed highly significant hypermethylation in tumor tissue (p Conclusion We have identified 22 DNA methylation markers for squamous cell lung cancer, several of which have not previously been reported to be methylated in any type of human cancer. The top eight markers show great promise as a sensitive and specific DNA methylation marker panel for squamous cell lung cancer.

  11. Curcumin Sensitizes Silymarin to Exert Synergistic Anticancer Activity in Colon Cancer Cells

    Science.gov (United States)

    Montgomery, Amanda; Adeyeni, Temitope; San, KayKay; Heuertz, Rita M.; Ezekiel, Uthayashanker R.

    2016-01-01

    We studied combinatorial interactions of two phytochemicals, curcumin and silymarin, in their action against cancer cell proliferation. Curcumin is the major component of the spice turmeric. Silymarin is a bioactive component of milk thistle used as a protective supplement against liver disease. We studied antiproliferative effects of curcumin alone, silymarin alone and combinations of curcumin and silymarin using colon cancer cell lines (DLD-1, HCT116, LoVo). Curcumin inhibited colon cancer cell proliferation in a concentration-dependent manner, whereas silymarin showed significant inhibition only at the highest concentrations assessed. We found synergistic effects when colon cancer cells were treated with curcumin and silymarin together. The combination treatment led to inhibition of colon cancer cell proliferation and increased apoptosis compared to single compound treated cells. Combination treated cells exhibited marked cell rounding and membrane blebbing of apoptotic cells. Curcumin treated cells showed 3-fold more caspase3/7 activity whereas combination treated cells showed 5-fold more activity compared to control and silymarin treated cells. When DLD-1 cells were pre-exposed to curcumin, followed by treatment with silymarin, the cells underwent a high amount of cell death. The pre-exposure studies indicated curcumin sensitization of silymarin effect. Our results indicate that combinatorial treatments using phytochemicals are effective against colorectal cancer. PMID:27390600

  12. Systematic identification of genomic markers of drug sensitivity in cancer cells.

    Science.gov (United States)

    Garnett, Mathew J; Edelman, Elena J; Heidorn, Sonja J; Greenman, Chris D; Dastur, Anahita; Lau, King Wai; Greninger, Patricia; Thompson, I Richard; Luo, Xi; Soares, Jorge; Liu, Qingsong; Iorio, Francesco; Surdez, Didier; Chen, Li; Milano, Randy J; Bignell, Graham R; Tam, Ah T; Davies, Helen; Stevenson, Jesse A; Barthorpe, Syd; Lutz, Stephen R; Kogera, Fiona; Lawrence, Karl; McLaren-Douglas, Anne; Mitropoulos, Xeni; Mironenko, Tatiana; Thi, Helen; Richardson, Laura; Zhou, Wenjun; Jewitt, Frances; Zhang, Tinghu; O'Brien, Patrick; Boisvert, Jessica L; Price, Stacey; Hur, Wooyoung; Yang, Wanjuan; Deng, Xianming; Butler, Adam; Choi, Hwan Geun; Chang, Jae Won; Baselga, Jose; Stamenkovic, Ivan; Engelman, Jeffrey A; Sharma, Sreenath V; Delattre, Olivier; Saez-Rodriguez, Julio; Gray, Nathanael S; Settleman, Jeffrey; Futreal, P Andrew; Haber, Daniel A; Stratton, Michael R; Ramaswamy, Sridhar; McDermott, Ultan; Benes, Cyril H

    2012-03-28

    Clinical responses to anticancer therapies are often restricted to a subset of patients. In some cases, mutated cancer genes are potent biomarkers for responses to targeted agents. Here, to uncover new biomarkers of sensitivity and resistance to cancer therapeutics, we screened a panel of several hundred cancer cell lines--which represent much of the tissue-type and genetic diversity of human cancers--with 130 drugs under clinical and preclinical investigation. In aggregate, we found that mutated cancer genes were associated with cellular response to most currently available cancer drugs. Classic oncogene addiction paradigms were modified by additional tissue-specific or expression biomarkers, and some frequently mutated genes were associated with sensitivity to a broad range of therapeutic agents. Unexpected relationships were revealed, including the marked sensitivity of Ewing's sarcoma cells harbouring the EWS (also known as EWSR1)-FLI1 gene translocation to poly(ADP-ribose) polymerase (PARP) inhibitors. By linking drug activity to the functional complexity of cancer genomes, systematic pharmacogenomic profiling in cancer cell lines provides a powerful biomarker discovery platform to guide rational cancer therapeutic strategies.

  13. Arsenic trioxide enhances the radiation sensitivity of androgen-dependent and -independent human prostate cancer cells.

    Directory of Open Access Journals (Sweden)

    Hui-Wen Chiu

    Full Text Available Prostate cancer is the most common malignancy in men. In the present study, LNCaP (androgen-sensitive human prostate cancer cells and PC-3 cells (androgen-independent human prostate cancer cells were used to investigate the anti-cancer effects of ionizing radiation (IR combined with arsenic trioxide (ATO and to determine the underlying mechanisms in vitro and in vivo. We found that IR combined with ATO increases the therapeutic efficacy compared to individual treatments in LNCaP and PC-3 human prostate cancer cells. In addition, combined treatment showed enhanced reactive oxygen species (ROS generation compared to treatment with ATO or IR alone in PC-3 cells. Combined treatment induced autophagy and apoptosis in LNCaP cells, and mainly induced autophagy in PC-3 cells. The cell death that was induced by the combined treatment was primarily the result of inhibition of the Akt/mTOR signaling pathways. Furthermore, we found that the combined treatment of cells pre-treated with 3-MA resulted in a significant change in AO-positive cells and cytotoxicity. In an in vivo study, the combination treatment had anti-tumor growth effects. These novel findings suggest that combined treatment is a potential therapeutic strategy not only for androgen-dependent prostate cancer but also for androgen-independent prostate cancer.

  14. KRAS mutation is a predictor of oxaliplatin sensitivity in colon cancer cells.

    Directory of Open Access Journals (Sweden)

    Yu-Lin Lin

    Full Text Available Molecular biomarkers to determine the effectiveness of targeted therapies in cancer treatment have been widely adopted in colorectal cancer (CRC, but those to predict chemotherapy sensitivity remain poorly defined. We tested our hypothesis that KRAS mutation may be a predictor of oxaliplatin sensitivity in CRC. KRAS was knocked-down in KRAS-mutant CRC cells (DLD-1(G13D and SW480(G12V by small interfering RNAs (siRNA and overexpressed in KRAS-wild-type CRC cells (COLO320DM by KRAS-mutant vectors to generate paired CRC cells. These paired CRC cells were tested by oxaliplatin, irinotecan and 5FU to determine the change in drug sensitivity by MTT assay and flow cytometry. Reasons for sensitivity alteration were further determined by western blot and real-time quantitative reverse transcriptase polymerase chain reaction (qRT -PCR. In KRAS-wild-type CRC cells (COLO320DM, KRAS overexpression by mutant vectors caused excision repair cross-complementation group 1 (ERCC1 downregulation in protein and mRNA levels, and enhanced oxaliplatin sensitivity. In contrast, in KRAS-mutant CRC cells (DLD-1(G13D and SW480(G12V, KRAS knocked-down by KRAS-siRNA led to ERCC1 upregulation and increased oxaliplatin resistance. The sensitivity of irinotecan and 5FU had not changed in the paired CRC cells. To validate ERCC1 as a predictor of sensitivity for oxaliplatin, ERCC1 was knocked-down by siRNA in KRAS-wild-type CRC cells, which restored oxaliplatin sensitivity. In contrast, ERCC1 was overexpressed by ERCC1-expressing vectors in KRAS-mutant CRC cells, and caused oxaliplatin resistance. Overall, our findings suggest that KRAS mutation is a predictor of oxaliplatin sensitivity in colon cancer cells by the mechanism of ERCC1 downregulation.

  15. Chemical biology drug sensitivity screen identifies sunitinib as synergistic agent with disulfiram in prostate cancer cells.

    Directory of Open Access Journals (Sweden)

    Kirsi Ketola

    Full Text Available BACKGROUND: Current treatment options for castration- and treatment-resistant prostate cancer are limited and novel approaches are desperately needed. Our recent results from a systematic chemical biology sensitivity screen covering most known drugs and drug-like molecules indicated that aldehyde dehydrogenase inhibitor disulfiram is one of the most potent cancer-specific inhibitors of prostate cancer cell growth, including TMPRSS2-ERG fusion positive cancers. However, the results revealed that disulfiram alone does not block tumor growth in vivo nor induce apoptosis in vitro, indicating that combinatorial approaches may be required to enhance the anti-neoplastic effects. METHODS AND FINDINGS: In this study, we utilized a chemical biology drug sensitivity screen to explore disulfiram mechanistic details and to identify compounds potentiating the effect of disulfiram in TMPRSS2-ERG fusion positive prostate cancer cells. In total, 3357 compounds including current chemotherapeutic agents as well as drug-like small molecular compounds were screened alone and in combination with disulfiram. Interestingly, the results indicated that androgenic and antioxidative compounds antagonized disulfiram effect whereas inhibitors of receptor tyrosine kinase, proteasome, topoisomerase II, glucosylceramide synthase or cell cycle were among compounds sensitizing prostate cancer cells to disulfiram. The combination of disulfiram and an antiangiogenic agent sunitinib was studied in more detail, since both are already in clinical use in humans. Disulfiram-sunitinib combination induced apoptosis and reduced androgen receptor protein expression more than either of the compounds alone. Moreover, combinatorial exposure reduced metastatic characteristics such as cell migration and 3D cell invasion as well as induced epithelial differentiation shown as elevated E-cadherin expression. CONCLUSIONS: Taken together, our results propose novel combinatorial approaches to inhibit

  16. Chemical Biology Drug Sensitivity Screen Identifies Sunitinib as Synergistic Agent with Disulfiram in Prostate Cancer Cells

    Science.gov (United States)

    Ketola, Kirsi; Kallioniemi, Olli; Iljin, Kristiina

    2012-01-01

    Background Current treatment options for castration- and treatment-resistant prostate cancer are limited and novel approaches are desperately needed. Our recent results from a systematic chemical biology sensitivity screen covering most known drugs and drug-like molecules indicated that aldehyde dehydrogenase inhibitor disulfiram is one of the most potent cancer-specific inhibitors of prostate cancer cell growth, including TMPRSS2-ERG fusion positive cancers. However, the results revealed that disulfiram alone does not block tumor growth in vivo nor induce apoptosis in vitro, indicating that combinatorial approaches may be required to enhance the anti-neoplastic effects. Methods and Findings In this study, we utilized a chemical biology drug sensitivity screen to explore disulfiram mechanistic details and to identify compounds potentiating the effect of disulfiram in TMPRSS2-ERG fusion positive prostate cancer cells. In total, 3357 compounds including current chemotherapeutic agents as well as drug-like small molecular compounds were screened alone and in combination with disulfiram. Interestingly, the results indicated that androgenic and antioxidative compounds antagonized disulfiram effect whereas inhibitors of receptor tyrosine kinase, proteasome, topoisomerase II, glucosylceramide synthase or cell cycle were among compounds sensitizing prostate cancer cells to disulfiram. The combination of disulfiram and an antiangiogenic agent sunitinib was studied in more detail, since both are already in clinical use in humans. Disulfiram-sunitinib combination induced apoptosis and reduced androgen receptor protein expression more than either of the compounds alone. Moreover, combinatorial exposure reduced metastatic characteristics such as cell migration and 3D cell invasion as well as induced epithelial differentiation shown as elevated E-cadherin expression. Conclusions Taken together, our results propose novel combinatorial approaches to inhibit prostate cancer cell

  17. The EGFR family of receptors sensitizes cancer cells towards UV light

    DEFF Research Database (Denmark)

    Petersen, Steffen B.; Neves Petersen, Teresa; Olsen, Birgitte

    2008-01-01

    A combination of bioinformatics, biophysical, advanced laser studies and cell biology lead to the realization that laser-pulsed UV light stops cancer growth and induces apoptosis. We have previously shown that laser-pulsed UV (LP-UV) illumination of two different skin-derived cancer cell lines both...... bridges. The EGF receptor is often overexpressed in cancers and other proliferative skin disorders, it might be possible to significantly reduce the proliferative potential of these cells making them good targets for laser-pulsed UV-light treatment. The discovery that UV light can be used to open...... that are sensitive to UV light lead to the prediction that UV light could modify these receptors permanently and stop cancer proliferation. We hereby show that the EGFR family of receptors has the necessary structural motifs that make this family of proteins highly sensitive to UV light....

  18. Ag nanoparticles sensitize IR-induced killing of cancer cells

    Institute of Scientific and Technical Information of China (English)

    Ruizhi Xu; Jun Ma; Xinchen Sun; Zhongping Chen; Xiaoli Jiang; Zhirui Guo; Lan Huang; Yang Li; Meng Wang; Changling Wang; Jiwei Liu; Xu Fan; Jiayu Gu; Xi Chen; Yu Zhang; Ning Gu

    2009-01-01

    @@ Dear Editor, Nanosized particulate systems combining better can-cer diagnosis with therapeutic effect are being designed based on the merging of nanotechnology with cellular and molecular techniques.

  19. Inhibition of Hec1 expression enhances the sensitivity of human ovarian cancer cells to paclitaxel

    Institute of Scientific and Technical Information of China (English)

    Qing-qing MO; Ping-bo CHEN; Xin JIN; Qian CHEN; Lan TANG; Bei-bei WANG; Ke-zhen LI

    2013-01-01

    Aim:Hec1,a member of the Ndc80 kinetochore complex,is highly expressed in cancers.The aim of this study was to explore the role and mechanism of action of Hec1 with respect to the cytotoxicity of paclitaxel in ovarian cancer.Methods:Thirty ovarian cancer samples and 6 normal ovarian samples were collected.Hec1 expression in these samples was determined with immunohistochemistry.Ovarian cancer cell lines A2780,OV2008,C13K,SKOV3,and CAOV3 and A2780/Taxol were examined.Cell apoptosis and cell cycle analysis were detected with flow cytometric technique.siRNA was used to delete Hec1 in the cells.The expression of related mRNAs and proteins was measured using RT-PCR and Western blot analysis,respectively.Results:Hec1 expression was significantly higher in ovarian cancer samples than in normal ovarian samples,and was associated with paclitaxel-resistance and poor prognosis.Among the 6 ovarian cancer cell lines examined,Hec1 expression was highest in paclitaxelresistant A2780/Taxol cells,and lowest in A2780 cells.Depleting Hec1 in A2780/Taxol cells with siRNA decreased the IC5o value of paclitaxel by more than 10-fold (from 590±26.7 to 45.6±19.4 nmol/L).Depleting Hec1 in A2780 cells had no significant effect on the paclitaxel sensitivity.In paclitaxel-treated A2780/Taxol cells,depleting Hec1 significantly increased the cleaved PARP and Bax protein levels,and decreased the Bcl-xL protein level.Conclusion:Hec1 overexpression is associated with the progression and poor prognosis of ovarian cancer.Inhibition of Hec1 expression can sensitize ovarian cancer cells to paclitaxel.

  20. Targeting cyclin B1 inhibits proliferation and sensitizes breast cancer cells to taxol

    Directory of Open Access Journals (Sweden)

    Strebhardt Klaus

    2008-12-01

    Full Text Available Abstract Background Cyclin B1, the regulatory subunit of cyclin-dependent kinase 1 (Cdk1, is essential for the transition from G2 phase to mitosis. Cyclin B1 is very often found to be overexpressed in primary breast and cervical cancer cells as well as in cancer cell lines. Its expression is correlated with the malignancy of gynecological cancers. Methods In order to explore cyclin B1 as a potential target for gynecological cancer therapy, we studied the effect of small interfering RNA (siRNA on different gynecological cancer cell lines by monitoring their proliferation rate, cell cycle profile, protein expression and activity, apoptosis induction and colony formation. Tumor formation in vivo was examined using mouse xenograft models. Results Downregulation of cyclin B1 inhibited proliferation of several breast and cervical cancer cell lines including MCF-7, BT-474, SK-BR-3, MDA-MB-231 and HeLa. After combining cyclin B1 siRNA with taxol, we observed an increased apoptotic rate accompanied by an enhanced antiproliferative effect in breast cancer cells. Furthermore, control HeLa cells were progressively growing, whereas the tumor growth of HeLa cells pre-treated with cyclin B1 siRNA was strongly inhibited in nude mice, indicating that cyclin B1 is indispensable for tumor growth in vivo. Conclusion Our data support the notion of cyclin B1 being essential for survival and proliferation of gynecological cancer cells. Concordantly, knockdown of cyclin B1 inhibits proliferation in vitro as well as in vivo. Moreover, targeting cyclin B1 sensitizes breast cancer cells to taxol, suggesting that specific cyclin B1 targeting is an attractive strategy for the combination with conventionally used agents in gynecological cancer therapy.

  1. Simultaneous inhibition of ATR and PARP sensitizes colon cancer cell lines to irinotecan

    Directory of Open Access Journals (Sweden)

    Atlal eAbu-Sanad

    2015-07-01

    Full Text Available Enhanced DNA damage repair is one mechanism involved in colon cancer drug resistance. Thus, targeting molecular components of repair pathways with specific small molecule inhibitors may improve the efficacy of chemotherapy. ABT-888 and VE-821, inhibitors of poly-ADP-ribose-polymerase (PARP and the serine/threonine-kinase Ataxia telangiectasia related (ATR, respectively, were used to treat colon cancer cell lines in combination with the topoisomerase-I inhibitor irinotecan (SN38. Our findings show that each of these DNA repair inhibitors utilized alone at nontoxic single agent concentrations resulted in sensitization to SN38 producing a 1.4 to 3 fold reduction in the 50% inhibitory concentration (IC50 of SN38 in three colon cancer cell lines. When combined together, nontoxic concentrations of ABT-888 and VE-821 produced a 4.5 to 27 fold reduction in the IC50 of SN38 with the HCT-116 colon cancer cells demonstrating the highest sensitization as compared to LoVo and HT-29 colon cancer cells. Furthermore, the combination of all three agents was associated with maximal G2-M arrest and enhanced DNA-damage (γH2AX in all three colon cancer cell lines. The mechanism of this enhanced sensitization was associated with: (a maximal suppression of SN38 induced PARP activity in the presence of both inhibitors and (b ABT-888 producing partial abrogation of the VE-821 enhancement of SN38 induced DNA-PK phosphorylation, resulting in more unrepaired DNA damage; these alterations were only present in the HCT-116 cells which have reduced levels of ATM. This novel combination of DNA repair inhibitors may be useful to enhance the activity of DNA damaging chemotherapies such as irinotecan and help produce sensitization to this drug in colon cancer.

  2. Regulation of GLUT transporters by flavonoids in androgen-sensitive and -insensitive prostate cancer cells.

    Science.gov (United States)

    Gonzalez-Menendez, Pedro; Hevia, David; Rodriguez-Garcia, Aida; Mayo, Juan C; Sainz, Rosa M

    2014-09-01

    Cancer cells show different metabolic requirements from normal cells. In prostate cancer, particularly, glycolytic metabolism differs in androgen-responsive and nonresponsive cells. In addition, some natural compounds with antiproliferative activities are able to modify glucose entry into cells by either modulating glucose transporter (GLUT) expression or by altering glucose binding. The aim of this work was to study the regulation of some GLUTs (GLUT1 and GLUT4) in both androgen-sensitive (LNCaP) and -insensitive (PC-3) prostate cancer cells by 4 structurally different flavonoids (ie, genistein, phloretin, apigenin, and daidzein). Glucose uptake was measured using nonradiolabeled 2-deoxyglucose. The evaluation of protein levels as well as subcellular distribution of GLUT1/4 were analyzed by Western blot and immunocytochemistry, respectively. Androgen-insensitive LNCaP-R and androgen-sensitive PC-3-AR cells were used to study the effect of androgen signaling. Additionally, a docking simulation was employed to compare interactions between flavonoids and XylE, a bacterial homolog of GLUT1 to -4. Results show for the first time the presence of functionally relevant GLUT4 in prostate cancer cells. Furthermore, differences in GLUT1 and GLUT4 levels and glucose uptake were found, without differences on subcellular distribution, after incubation with flavonoids. Docking simulation showed that all compounds interact with the same location of transporters. More importantly, differences between androgen-sensitive and -insensitive prostate cancer cells were found in both GLUT protein levels and glucose uptake. Thus, phenotypic characteristics of prostate cancer cells are responsible for the different effects of these flavonoids in glucose uptake and in GLUT expression rather than their structural differences, with the most effective in reducing cell growth being the highest in modifying glucose uptake and GLUT levels.

  3. The Cancer Cell Line Encyclopedia enables predictive modelling of anticancer drug sensitivity.

    Science.gov (United States)

    Barretina, Jordi; Caponigro, Giordano; Stransky, Nicolas; Venkatesan, Kavitha; Margolin, Adam A; Kim, Sungjoon; Wilson, Christopher J; Lehár, Joseph; Kryukov, Gregory V; Sonkin, Dmitriy; Reddy, Anupama; Liu, Manway; Murray, Lauren; Berger, Michael F; Monahan, John E; Morais, Paula; Meltzer, Jodi; Korejwa, Adam; Jané-Valbuena, Judit; Mapa, Felipa A; Thibault, Joseph; Bric-Furlong, Eva; Raman, Pichai; Shipway, Aaron; Engels, Ingo H; Cheng, Jill; Yu, Guoying K; Yu, Jianjun; Aspesi, Peter; de Silva, Melanie; Jagtap, Kalpana; Jones, Michael D; Wang, Li; Hatton, Charles; Palescandolo, Emanuele; Gupta, Supriya; Mahan, Scott; Sougnez, Carrie; Onofrio, Robert C; Liefeld, Ted; MacConaill, Laura; Winckler, Wendy; Reich, Michael; Li, Nanxin; Mesirov, Jill P; Gabriel, Stacey B; Getz, Gad; Ardlie, Kristin; Chan, Vivien; Myer, Vic E; Weber, Barbara L; Porter, Jeff; Warmuth, Markus; Finan, Peter; Harris, Jennifer L; Meyerson, Matthew; Golub, Todd R; Morrissey, Michael P; Sellers, William R; Schlegel, Robert; Garraway, Levi A

    2012-03-28

    The systematic translation of cancer genomic data into knowledge of tumour biology and therapeutic possibilities remains challenging. Such efforts should be greatly aided by robust preclinical model systems that reflect the genomic diversity of human cancers and for which detailed genetic and pharmacological annotation is available. Here we describe the Cancer Cell Line Encyclopedia (CCLE): a compilation of gene expression, chromosomal copy number and massively parallel sequencing data from 947 human cancer cell lines. When coupled with pharmacological profiles for 24 anticancer drugs across 479 of the cell lines, this collection allowed identification of genetic, lineage, and gene-expression-based predictors of drug sensitivity. In addition to known predictors, we found that plasma cell lineage correlated with sensitivity to IGF1 receptor inhibitors; AHR expression was associated with MEK inhibitor efficacy in NRAS-mutant lines; and SLFN11 expression predicted sensitivity to topoisomerase inhibitors. Together, our results indicate that large, annotated cell-line collections may help to enable preclinical stratification schemata for anticancer agents. The generation of genetic predictions of drug response in the preclinical setting and their incorporation into cancer clinical trial design could speed the emergence of 'personalized' therapeutic regimens.

  4. Blockage of IGF-1R signaling sensitizes urinary bladder cancer cells to mitomycin-mediated cytotoxicity

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A major problem which is poorly understood in the management of bladder cancer is low sensitivity to chemotherapy and high recurrence after transurethral resection.Insulin-like growth factor 1 receptor(IGF-1R)signaling plays a very important role in progression,invasion and metastasis of bladder cancer cells.In this study,we investigated whether IGF-1R was involved in the growth stimulating activity and drug resistance of bladder cancer cells.The results showed: The mRNAs of IGF-1,IGF-2 and IGF-1R were strongly expressed in serum-free cultured T24 cell line,whereas normal urothelial cells did not express these factors/receptors or only in trace levels; T24 cell responded far better to growth stimulation by IGF-1 than did normal urothelial cells; blockage of IGF1R by antisense oligodeoxynucleotide(ODN)significantly inhibited the growth of T24 cell and enhanced sensitivity and apoptosis of T24 cells to mitomycin(MMC).These results suggested that blockage of IGF-IR signaling might potentially contribute to the treatment of bladder cancer cells which are insensitive to chemotherapy.

  5. Noscapine sensitizes chemoresistant ovarian cancer cells to cisplatin through inhibition of HIF-1α.

    Science.gov (United States)

    Su, Wenjing; Huang, Lei; Ao, Qilin; Zhang, Qinghua; Tian, Xun; Fang, Yong; Lu, Yunping

    2011-06-01

    Hypoxia-inducible factor 1 alpha (HIF-1α) is closely related with chemoresistance of solid tumors. The purpose of this study was to investigate the ability of noscapine to inhibit HIF-1α and sensitize ovarian cancer cells to cisplatin (DDP) under hypoxic conditions. Herein, we report that noscapine sensitized cobalt-induced chemoresistant ovarian cancer cells to DDP-induced apoptosis and inhibition of cell proliferation. Noscapine also promoted proteasome-mediated degradation of cobalt-stabilized HIF-1α protein, with subsequent inhibition of HIF-1 transcriptional activity. These data establish noscapine as a small molecule inhibitor of HIF-1α and provide an evidence for its combination with DDP in combating ovarian cancer chemoresistance.

  6. The molecular mechanism of different sensitivity of breast cancer cell lines to TRAIL

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jindan; LIU Yanxin; LIU Shilian; ZHENG Dexian

    2004-01-01

    Although Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) selectively induces apoptosis of various cancer cells, some caner cell lines are resistant to TRAIL-induced cell death. To investigate the molecular mechanisms underlying TRAIL-resistance, two human breast cancer cell lines, MCF-7 (resistant to TRAIL) and MDA-MB-231 (sensitive to TRAIL), were used as a model system to analyze the different sensitivities to TRAIL cytotoxicity. PKCδ inhibitor rottlerin, but not MEK and ERK1/2 inhibitor U0126 nor PI3K inhibitor LY294002, was shown to enhance TRAIL-induced apoptosis in MCF-7 cells significantly, suggesting that PKCδ might play an important role in the resistance of MCF-7 cells to TRAIL. In contrast, rottlerin, U0126, and Ly294002 had no effect on MDA-MB-231 apoptosis induced by TRAIL under the same conditions. Further experiment showed that the combination of rottlerin and TRAIL cleaved PARP in the MCF-7 cells synergistically, but not in the MDA-MB-231 cells. The role of PKCδ in TRAIL-resistant MCF-7 cells was confirmed by knocking down the endogenous PKCδ expression using RNAi technology. Furthermore, caspase-3 reconstitution in MCF-7 cells was unable to alter PKCδ expression, suggesting that innate caspase-3 deficient in the cells does not cause PKCδ high expression. These data provide evidence for the first time that PKCδ plays a critical role in breast cancer cell lines to TRAIL cytotoxicity.

  7. BRCA1 deficiency increases the sensitivity of ovarian cancer cells to auranofin

    Energy Technology Data Exchange (ETDEWEB)

    Oommen, Deepu [School of Biological Sciences, Plymouth University, Plymouth PL4 8AA (United Kingdom); Yiannakis, Dennis [Plymouth Oncology Centre, Derriford Hospital, Plymouth Hospitals NHS Trust, Plymouth PL6 8DH (United Kingdom); Jha, Awadhesh N., E-mail: a.jha@plymouth.ac.uk [School of Biological Sciences, Plymouth University, Plymouth PL4 8AA (United Kingdom)

    2016-02-15

    Highlights: • BRCA1 deficient cancer cells exhibit increased DNA damage upon auranofin treatment. • Auranofin induces apoptosis in BRCA1 deficient cancer cells despite the activation of Nrf2. • Antioxidant protects BRCA1 deficient cancer cells from auranofin. - Abstract: Auranofin, a thioredoxin reductase inhibitor and an anti-rheumatic drug is currently undergoing phase 2 clinical studies for repurposing to treat recurrent epithelial ovarian cancer. Previous studies have established that auranofin exerts its cytotoxic activity by increasing the production of reactive oxygen species (ROS). Breast cancer 1, early onset (BRCA1) is a DNA repair protein whose functional status is critical in the prognosis of ovarian cancer. Apart from its key role in DNA repair, BRCA1 is also known to modulate cellular redox homeostasis by regulating the stability of anti-oxidant transcription factor, nuclear factor erythroid 2—related factor 2 (Nrf2) via direct protein–protein interaction. However, it is currently unknown whether BRCA1 modulates the sensitivity of ovarian cancer cells to auranofin. Here we report that BRCA1-depleted cells exhibited increased DNA double strand breaks (DSBs) and decreased clonogenic cell survival upon auranofin treatment. Interestingly, auranofin induced the expression of Nrf2 in BRCA1-depleted cells suggesting its regulation independent of BRCA1. Furthermore, anti-oxidant agent, N-acetyl cysteine (NAC) protected BRCA1-depleted cells from DNA damage and apoptosis induced by auranofin. Our study suggests that accumulated lethal DSBs resulting from the oxidative damage render BRCA1 deficient cells more sensitive to auranofin despite the activation of Nrf2.

  8. Survivin gene silencing sensitizes prostate cancer cells to selenium growth inhibition

    Directory of Open Access Journals (Sweden)

    Liu Xichun

    2010-08-01

    Full Text Available Abstract Background Prostate cancer is a leading cause of cancer-related death in men worldwide. Survivin is a member of the inhibitor of apoptosis (IAP protein family that is expressed in the majority of human tumors including prostate cancer, but is barely detectable in terminally differentiated normal cells. Downregulation of survivin could sensitize prostate cancer cells to chemotherapeutic agents in vitro and in vivo. Selenium is an essential trace element. Several studies have shown that selenium compounds inhibit the growth of prostate cancer cells. The objective of this study is to investigate whether survivin gene silencing in conjunction with selenium treatment could enhance the therapeutic efficacy for prostate cancer and to elucidate the underlying mechanisms. Methods Expression of survivin was analyzed in a collection of normal and malignant prostatic tissues by immunohistochemical staining. In vitro studies were conducted in PC-3M, C4-2B, and 22Rv1 prostate cancer cells. The effect of selenium on survivin expression was analyzed by Western blotting and semi-quantitative RT-PCR. Survivin gene knockdown was carried out by transfecting cells with a short hairpin RNA (shRNA designed against survivin. Cell proliferation was quantitated by the 3-(4,5-Dimethylthiazol-2-yl- 2,5-Diphenyltetrazolium Bromide (MTT assay and apoptosis by propidium iodide staining followed by flow cytometry analysis. Finally, in vivo tumor growth assay was performed by establishing PC-3M xenograft in nude mice and monitoring tumor growth following transfection and treatment. Results We found that survivin was undetectable in normal prostatic tissues but was highly expressed in prostate cancers. Survivin knockdown or selenium treatment inhibited the growth of prostate cancer cells, but the selenium effect was modest. In contrast to what have been observed in other cell lines, selenium treatment had little or no effect on survivin expression in several androgen

  9. Methylseleninic acid sensitizes Notch3-activated OVCA429 ovarian cancer cells to carboplatin.

    Directory of Open Access Journals (Sweden)

    Tiffany J Tzeng

    Full Text Available Ovarian cancer, the deadliest of gynecologic cancers, is usually not diagnosed until advanced stages. Although carboplatin has been popular for treating ovarian cancer for decades, patients eventually develop resistance to this platinum-containing drug. Expression of neurogenic locus notch homolog 3 (Notch3 is associated with chemoresistance and poor overall survival in ovarian cancer patients. Overexpression of NICD3 (the constitutively active form of Notch3 in OVCA429 ovarian cancer cells (OVCA429/NICD3 renders them resistance to carboplatin treatment compared to OVCA429/pCEG cells expressing an empty vector. We have previously shown that methylseleninic acid (MSeA induces oxidative stress and activates ataxia-telangiectasia mutated and DNA-dependent protein kinase in cancer cells. Here we tested the hypothesis that MSeA and carboplatin exerted a synthetic lethal effect on OVCA429/NICD3 cells. Co-treatment with MSeA synergistically sensitized OVCA429/NICD3 but not OVCA429/pCEG cells to the killing by carboplatin. This synergism was associated with a cell cycle exit at the G2/M phase and the induction of NICD3 target gene HES1. Treatment of N-acetyl cysteine or inhibitors of the above two kinases did not directly impact on the synergism in OVCA429/NICD3 cells. Taken together, these results suggest that the efficacy of carboplatin in the treatment of high grade ovarian carcinoma can be enhanced by a combinational therapy with MSeA.

  10. rAd-p53 enhances the sensitivity of human gastric cancer cells to chemotherapy

    Institute of Scientific and Technical Information of China (English)

    Guang-Xia Chen; Li-Hong Zheng; Shi-Yu Liu; Xiao-Hua He

    2011-01-01

    AIM:To investigate potential antitumor effects of rAd-p53 by determining if it enhanced sensitivity of gastric cancer cells to chemotherapy.METHODS:Three gastric cancer cell lines with distinct levels of differentiation were treated with various doses of rAd-p53 alone,oxaliplatin (OXA) alone,or a combination of both.Cell growth was assessed with an 3-(4,5)-dimethylthiahiazo (-z-yl)-3,5-diphenytetrazoli-umromide assay and the expression levels of p53,Bax and Bcl-2 were determined by immunohistochemistry.The presence of apoptosis and the expression of cas-pase-3 were determined using flow cytometry.RESULTS:Treatment with rAd-p53 or OXA alone inhibited gastric cancer cell growth in a time- and dose-dependent manner;moreover,significant synergistic effects were observed when these treatments were combined.Immunohistochemical analysis demonstrated that treatment with rAd-p53 alone,OXA alone or combined treatment led to decreased Bcl-2 expression and increased Bax expression in gastric cancer cells.Furthermore,flow cytometry showed that rAd-p53 alone,OXA alone or combination treatment induced apoptosis of gastric cancer cells,which was accompanied by increased expression of caspase-3.CONCLUSION:rAd-p53 enhances the sensitivity of gastric cancer cells to chemotherapy by promoting apoptosis.Thus,our results suggest that p53 gene therapy combined with chemotherapy represents a novel avenue for gastric cancer treatment.

  11. Docosahexaenoic acid sensitizes colon cancer cells to sulindac sulfide-induced apoptosis.

    Science.gov (United States)

    Lim, Soo-Jeong; Lee, Eunmyong; Lee, Eun-Hye; Kim, Soo-Yeon; Cha, Jun Hyung; Choi, Hwanho; Park, Wanseo; Choi, Hyeon Kyeom; Ko, Seong-Hee; Kim, So Hee

    2012-06-01

    Sulindac analogs represent one of the most efficacious groups of NSAIDs reducing the risk of colon cancer. Recent studies have shown that sulindac sulfide, a sulindac analog effective at lower doses compared to its parent compound, triggers the death receptor (DR)5-dependent extrinsic apoptotic pathway. Induction of apoptosis via activation of the DR-mediated pathway would be an ideal therapeutic strategy to eliminate cancer cells. In this study, we investigated the possibility that colon cancer cells are sensitized to sulindac sulfide-induced apoptosis by docosahexaenoic acid (DHA), via activation of the DR/extrinsic apoptotic pathway. Our data demonstrated that DHA combination sensitized colon cancer cells to sulindac sulfide-induced apoptosis, leading to enhanced growth suppression of human colon cancer xenografts. The combination effect was primarily attributed to increased cleavage of poly(ADP-ribose) polymerase (PARP) and caspase-8 activation. Moreover, pretreatment with z-IETD-FMK (caspase-8 inhibitor) or stable expression of dominant negative caspase-8 genes blocked DHA/sulindac sulfide cotreatment-induced apoptosis. In view of the finding that DR5 silencing abrogated the combination-stimulated apoptosis, we propose that apoptotic synergy induced by sulindac sulfide plus DHA is mediated via DR5. Our findings collectively support the utility of a combination of sulindac sulfide and DHA in the effective prevention and treatment of colon cancer.

  12. Dynamic modulation of thymidylate synthase gene expression and fluorouracil sensitivity in human colorectal cancer cells.

    Directory of Open Access Journals (Sweden)

    Kentaro Wakasa

    Full Text Available Biomarkers have revolutionized cancer chemotherapy. However, many biomarker candidates are still in debate. In addition to clinical studies, a priori experimental approaches are needed. Thymidylate synthase (TS expression is a long-standing candidate as a biomarker for 5-fluorouracil (5-FU treatment of cancer patients. Using the Tet-OFF system and a human colorectal cancer cell line, DLD-1, we first constructed an in vitro system in which TS expression is dynamically controllable. Quantitative assays have elucidated that TS expression in the transformant was widely modulated, and that the dynamic range covered 15-fold of the basal level. 5-FU sensitivity of the transformant cells significantly increased in response to downregulated TS expression, although being not examined in the full dynamic range because of the doxycycline toxicity. Intriguingly, our in vitro data suggest that there is a linear relationship between TS expression and the 5-FU sensitivity in cells. Data obtained in a mouse model using transformant xenografts were highly parallel to those obtained in vitro. Thus, our in vitro and in vivo observations suggest that TS expression is a determinant of 5-FU sensitivity in cells, at least in this specific genetic background, and, therefore, support the possibility of TS expression as a biomarker for 5-FU-based cancer chemotherapy.

  13. Non-specific chemical inhibition of the Fanconi anemia pathway sensitizes cancer cells to cisplatin

    Directory of Open Access Journals (Sweden)

    Jacquemont Céline

    2012-04-01

    Full Text Available Abstract Background Platinum compounds such as cisplatin and carboplatin are DNA crosslinking agents widely used for cancer chemotherapy. However, the effectiveness of platinum compounds is often tempered by the acquisition of cellular drug resistance. Until now, no pharmacological approach has successfully overcome cisplatin resistance in cancer treatment. Since the Fanconi anemia (FA pathway is a DNA damage response pathway required for cellular resistance to DNA interstrand crosslinking agents, identification of small molecules that inhibit the FA pathway may reveal classes of chemicals that sensitize cancer cells to cisplatin. Results Through a cell-based screening assay of over 16,000 chemicals, we identified 26 small molecules that inhibit ionizing radiation and cisplatin-induced FANCD2 foci formation, a marker of FA pathway activity, in multiple human cell lines. Most of these small molecules also compromised ionizing radiation-induced RAD51 foci formation and homologous recombination repair, indicating that they are not selective toward the regulation of FANCD2. These compounds include known inhibitors of the proteasome, cathepsin B, lysosome, CHK1, HSP90, CDK and PKC, and several uncharacterized chemicals including a novel proteasome inhibitor (Chembridge compound 5929407. Isobologram analyses demonstrated that half of the identified molecules sensitized ovarian cancer cells to cisplatin. Among them, 9 demonstrated increased efficiency toward FA pathway-proficient, cisplatin-resistant ovarian cancer cells. Six small molecules, including bortezomib (proteasome inhibitor, CA-074-Me (cathepsin B inhibitor and 17-AAG (HSP90 inhibitor, synergized with cisplatin specifically in FA-proficient ovarian cancer cells (2008 + FANCF, but not in FA-deficient isogenic cells (2008. In addition, geldanamycin (HSP90 inhibitor and two CHK1 inhibitors (UCN-01 and SB218078 exhibited a significantly stronger synergism with cisplatin in FA

  14. Silver nanocrystals sensitize magnetic-nanoparticle-mediated thermo-induced killing of cancer cells

    Institute of Scientific and Technical Information of China (English)

    Lianke Liu; Fang Ni; Jianchao Zhang; Xiaoli Jiang; Xiang Lu; Zhirui Guo; Ruizhi Xu

    2011-01-01

    Magnetic nanoparticles (MNPs) can heat up tumor tissues and induce killing of cancer cells under external AC magnetic field. However, magnetic nanoparticles hyperthermia (MNPH) requires high concentration of MNPs that are injected into the tumor in order to obtain clinically needed thermal dose because of the complicated heat transfer in v/vo and the limited heat quality of MNPs. To cut down the dose of MNPs and enhance the effect of this Nanotherapy, we prepared silver nanoparticles (AgNPs) with different sizes and investigated the effects of these AgNPs on cancer cells in MNPH treatment. It was found that AgNPs could enhance thermo-sensitivity of glioma cells and this effect was size dependent. AgNPs could induce cell cycles arrested in G2/M phase and enhanced the apoptosis rate of cancer cells after hyperthermia. In glioma bearing rats model, MNPH combined with AgNPs could enhance Bax expression in cancer cells. Our results suggested that AgNPs could be a potential thermo-sensitizer and could be further developed for the design of Ag nanostructurebased thermal seeds for MNPH therapy.

  15. Prediction of cancer cell sensitivity to natural products based on genomic and chemical properties

    Directory of Open Access Journals (Sweden)

    Zhenyu Yue

    2015-11-01

    Full Text Available Natural products play a significant role in cancer chemotherapy. They are likely to provide many lead structures, which can be used as templates for the construction of novel drugs with enhanced antitumor activity. Traditional research approaches studied structure-activity relationship of natural products and obtained key structural properties, such as chemical bond or group, with the purpose of ascertaining their effect on a single cell line or a single tissue type. Here, for the first time, we develop a machine learning method to comprehensively predict natural products responses against a panel of cancer cell lines based on both the gene expression and the chemical properties of natural products. The results on two datasets, training set and independent test set, show that this proposed method yields significantly better prediction accuracy. In addition, we also demonstrate the predictive power of our proposed method by modeling the cancer cell sensitivity to two natural products, Curcumin and Resveratrol, which indicate that our method can effectively predict the response of cancer cell lines to these two natural products. Taken together, the method will facilitate the identification of natural products as cancer therapies and the development of precision medicine by linking the features of patient genomes to natural product sensitivity.

  16. Prediction of cancer cell sensitivity to natural products based on genomic and chemical properties.

    Science.gov (United States)

    Yue, Zhenyu; Zhang, Wenna; Lu, Yongming; Yang, Qiaoyue; Ding, Qiuying; Xia, Junfeng; Chen, Yan

    2015-01-01

    Natural products play a significant role in cancer chemotherapy. They are likely to provide many lead structures, which can be used as templates for the construction of novel drugs with enhanced antitumor activity. Traditional research approaches studied structure-activity relationship of natural products and obtained key structural properties, such as chemical bond or group, with the purpose of ascertaining their effect on a single cell line or a single tissue type. Here, for the first time, we develop a machine learning method to comprehensively predict natural products responses against a panel of cancer cell lines based on both the gene expression and the chemical properties of natural products. The results on two datasets, training set and independent test set, show that this proposed method yields significantly better prediction accuracy. In addition, we also demonstrate the predictive power of our proposed method by modeling the cancer cell sensitivity to two natural products, Curcumin and Resveratrol, which indicate that our method can effectively predict the response of cancer cell lines to these two natural products. Taken together, the method will facilitate the identification of natural products as cancer therapies and the development of precision medicine by linking the features of patient genomes to natural product sensitivity.

  17. Androgen receptor signaling is required for androgen-sensitive human prostate cancer cell proliferation and survival

    Directory of Open Access Journals (Sweden)

    Day Wanda V

    2005-04-01

    Full Text Available Abstract Background Androgens and androgen receptors (AR regulate normal prostate development and growth. They also are involved in pathological development of prostatic diseases, including benign prostatic hyperplasia (BPH and prostate cancer (PCa. Antiandrogen therapy for PCa, in conjunction with chemical or surgical castration, offers initial positive responses and leads to massive prostate cell death. However, cancer cells later appear as androgen-independent PCa. To investigate the role of AR in prostate cell proliferation and survival, we introduced a vector-based small interfering RNA (siRNA. This siRNA targeted 5'-untranslated region of AR mRNA for extended suppression of AR expression in androgen-sensitive human prostate LNCaP cells. Results The siRNA design successfully suppressed endogenous AR expression, as revealed by western blotting and immunofluorescence staining in LNCaP cells. LNCaP cells did not proliferate in the absence of AR and underwent apoptosis, based on elevated phospho-Histone H2B expression and higher number of apoptotic body as compared to control cells. Conclusion We demonstrated that AR is vital for prostate cell proliferation and survival in this androgen-sensitive prostate cell line. These results further strengthen the hypothesis that AR can be a therapeutic target for treating androgen-sensitive stages of PCa. Unlike antiandorgens, however, siRNA targeting AR provides a direct inactivation of AR function through the suppression of AR protein expression.

  18. Zinc inhibits nuclear factor-kappa B activation and sensitizes prostate cancer cells to cytotoxic agents.

    Science.gov (United States)

    Uzzo, Robert G; Leavis, Paul; Hatch, William; Gabai, Vladimir L; Dulin, Nickolai; Zvartau, Nadezhda; Kolenko, Vladimir M

    2002-11-01

    Prostate carcinogenesis involves transformation of zinc-accumulating normal epithelial cells to malignant cells, which do not accumulate zinc. In this study, we demonstrate by immunoblotting and immunohistochemistry that physiological levels of zinc inhibit activation of nuclear factor (NF)-kappa B transcription factor in PC-3 and DU-145 human prostate cancer cells, reduce expression of NF-kappa B-controlled antiapoptotic protein c-IAP2, and activate c-Jun NH(2)-terminal kinases. Preincubation of PC-3 cells with physiological concentrations of zinc sensitized tumor cells to tumor necrosis factor (TNF)-alpha, and paclitaxel mediated cell death as defined by terminal deoxynucleotidyl transferase-mediated nick end labeling assay. These results suggest one possible mechanism for the inhibitory effect of zinc on the development and progression of prostate malignancy and might have important consequences for the prevention and treatment of prostate cancer.

  19. Inhibition of JNK Sensitizes Hypoxic Colon Cancer Cells to DNA Damaging Agents

    Science.gov (United States)

    Vasilevskaya, Irina A.; Selvakumaran, Muthu; Hierro, Lucia Cabal; Goldstein, Sara R.; Winkler, Jeffrey D.; O'Dwyer, Peter J.

    2015-01-01

    Purpose We showed previously that in HT29 colon cancer cells, modulation of hypoxia-induced stress signaling affects oxaliplatin cytotoxicity. To further study the significance of hypoxia-induced signaling through JNK, we set out to investigate how modulation of kinase activities influences cellular responses of hypoxic colon cancer cells to cytotoxic drugs. Experimental design In a panel of cell lines we investigated effects of pharmacological and molecular inhibition of JNK on sensitivity to oxaliplatin, SN-38 and 5-FU. Combination studies for the drugs and JNK inhibitor CC-401 were carried out in vitro and in vivo. Results Hypoxia-induced JNK activation was associated with resistance to oxaliplatin. CC-401 in combination with chemotherapy demonstrates synergism in colon cancer cell lines, though synergy is not always hypoxia-specific. A more detailed analysis focused on HT29 and SW620 (responsive), and HCT116 (non-responsive) lines. In HT29 and SW620 cells CC-401 treatment results in greater DNA damage in the sensitive cells. In vivo, potentiation of bevacizumab, oxaliplatin, and the combination by JNK inhibition was confirmed in HT29-derived mouse xenografts, where tumor growth delay was greater in the presence of CC-401. Finally, stable introduction of a dominant negative JNK1, but not JNK2, construct into HT29 cells rendered them more sensitive to oxaliplatin under hypoxia, suggesting differing input of JNK isoforms in cellular responses to chemotherapy. Conclusions These findings demonstrate that signaling through JNK is a determinant of response to therapy in colon cancer models, and support the testing of JNK inhibition to sensitize colon tumors in the clinic. PMID:26023085

  20. Salinomycin sensitizes antimitotic drugs-treated cancer cells by increasing apoptosis via the prevention of G2 arrest

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ju-Hwa; Yoo, Hye-In; Kang, Han Sung; Ro, Jungsil [Research Institute, National Cancer Center, Ilsan-gu, Goyang-si, Gyeonggi-do (Korea, Republic of); Yoon, Sungpil, E-mail: yoons@ncc.re.kr [Research Institute, National Cancer Center, Ilsan-gu, Goyang-si, Gyeonggi-do (Korea, Republic of)

    2012-02-03

    Highlights: Black-Right-Pointing-Pointer Sal sensitizes antimitotic drugs-treated cancer cells. Black-Right-Pointing-Pointer Sal sensitizes them by prevention of G2 arrest and reduced cyclin D1 levels. Black-Right-Pointing-Pointer Sal also sensitizes them by increasing DNA damage and reducing p21 level. Black-Right-Pointing-Pointer A low concentration of Sal effectively sensitized the cancer cells to antimitotic drugs. -- Abstract: Here, we investigated whether Sal could sensitize cancer cells to antimitotic drugs. We demonstrated that Sal sensitized paclitaxcel (PAC)-, docetaxcel (DOC)-, vinblastin (VIN)-, or colchicine (COL)-treated cancer cell lines, suggesting that Sal has the ability to sensitize the cells to any form of microtubule-targeting drugs. Sensitization to the antimitotic drugs could be achieved with very low concentrations of Sal, suggesting that there is a possibility to minimize Sal toxicity associated with human cancer patient treatments. Sensitization by Sal increased apoptosis, which was observed by C-PARP production. Sal sensitized the cancer cells to antimitotic drugs by preventing G2 arrest, suggesting that Sal contributes to the induction of mitotic catastrophe. Sal generally reduced cyclin D1 levels in PAC-, DOC-, and VIN-treated cells. In addition, Sal treatment increased pH2AX levels and reduced p21 levels in antimitotic drugs-treated cells. These observations suggest that the mechanisms underlying Sal sensitization to DNA-damaging compounds, radiation, and microtubule-targeting drugs are similar. Our data demonstrated that Sal sensitizes cancer cells to antimitotic drugs by increasing apoptosis through the prevention of G2 arrest via conserved Sal-sensitization mechanisms. These results may contribute to the development of Sal-based chemotherapy for cancer patients treated with antimitotic drugs.

  1. miRNAs associated with chemo-sensitivity in cell lines and in advanced bladder cancer

    DEFF Research Database (Denmark)

    Nordentoft, Iver; Birkenkamp-Demtroder, Karin; Agerbæk, Mads;

    2012-01-01

    Background MicroRNA is a naturally occurring class of non-coding RNA molecules that mediate posttranscriptional gene regulation and are strongly implicated in cellular processes such as cell proliferation, carcinogenesis, cell survival and apoptosis. Consequently there is increasing focus on mi......RNA expression as prognostic factors for outcome and chemotherapy response. Only approximately 50% of patients with bladder cancer respond to chemotherapy. Therefore, predictive markers, such as miRNAs, that can identify subgroups of patients who will benefit from chemotherapy will have great value for treatment...... with progressive disease and in tumors form patients with short and long overall survival time. Furthermore, we studied the effect of up- and down regulation of key miRNAs on the cisplatin sensitivity in eight bladder cancer cell lines with different sensitivities to cisplatin. Results miRNA expression profiling...

  2. Highly sensitive detection of cancer cells with an electrochemical cytosensor based on boronic acid functional polythiophene.

    Science.gov (United States)

    Dervisevic, Muamer; Senel, Mehmet; Sagir, Tugba; Isik, Sevim

    2017-04-15

    The detection of cancer cells through important molecular recognition target such as sialic acid is significant for the clinical diagnosis and treatment. There are many electrochemical cytosensors developed for cancer cells detection but most of them have complicated fabrication processes which results in poor reproducibility and reliability. In this study, a simple, low-cost, and highly sensitive electrochemical cytosensor was designed based on boronic acid-functionalized polythiophene. In cytosensors fabrication simple single-step procedure was used which includes coating pencil graphite electrode (PGE) by means of electro-polymerization of 3-Thienyl boronic acid and Thiophen. Electrochemical impedance spectroscopy and cyclic voltammetry were used as an analytical methods to optimize and measure analytical performances of PGE/P(TBA0.5Th0.5) based electrode. Cytosensor showed extremely good analytical performances in detection of cancer cells with linear rage of 1×10(1) to 1×10(6) cellsmL(-1) exhibiting low detection limit of 10 cellsmL(-1) and incubation time of 10min. Next to excellent analytical performances, it showed high selectivity towards AGS cancer cells when compared to HEK 293 normal cells and bone marrow mesenchymal stem cells (BM-hMSCs). This method is promising for future applications in early stage cancer diagnosis.

  3. Overexpression of Bax sensitizes prostate cancer cells to TGF-β induced apoptosis

    Institute of Scientific and Technical Information of China (English)

    Pei Hui LIN; Zui PAN; Lin ZHENG; Na LI; David DANIELPOUR; Jian Jie MA

    2005-01-01

    NRP-154 is a tumorigenic epithelial cell line derived from the preneoplastic dorsal-lateral prostate of rats. These cells are exquisitely sensitive to TGF-β induced apoptosis. In contrast, we find that NRP-154 cells can sustain overexpression of exogenous Bax protein, which is different from non-tumor cells where Bax functions as a ubiquitous stimulator of apoptosis. NRP-154 cells stably overexpressing Bax show increased sensitivity to TGF-β induced apoptosis. The degree of TGF-β induced apoptosis displays high correlation with cleavage of Bax at the amino-terminus. Our data indicate that prostate cancer cells can host high levels of latent Bax which can be activated through post-translational modification.

  4. Constitutively activated ERK sensitizes cancer cells to doxorubicin: Involvement of p53-EGFR-ERK pathway

    Indian Academy of Sciences (India)

    RATNA KUMARI; SURBHI CHOUHAN; SNAHLATA SINGH; RISHI RAJ CHHIPA; AMRENDRA KUMAR AJAY; MANOJ KUMAR BHAT

    2017-03-01

    The tumour suppressor gene p53 is mutated in approximately 50% of the human cancers. p53 is involved in genotoxicstress-induced cellular responses. The role of EGFR and ERK in DNA-damage-induced apoptosis is well known. Weinvestigated the involvement of activation of ERK signalling as a consequence of non-functional p53, in sensitivity ofcells to doxorubicin. We performed cell survival assays in cancer cell lines with varying p53 status: MCF-7 (wild-typep53, WTp53), MDA MB-468 (mutant p53, MUTp53), H1299 (absence of p53, NULLp53) and an isogenic cell lineMCF-7As (WTp53 abrogated). Our results indicate that enhanced chemosensitivity of cells lacking wild-type p53function is because of elevated levels of EGFR which activates ERK. Additionally, we noted that independent of p53status, pERK contributes to doxorubicin-induced cell death.

  5. Reduction of Orc6 expression sensitizes human colon cancer cells to 5-fluorouracil and cisplatin.

    Directory of Open Access Journals (Sweden)

    Elaine J Gavin

    Full Text Available Previous studies from our group have shown that the expression levels of Orc6 were highly elevated in colorectal cancer patient specimens and the induction of Orc6 was associated with 5-fluorouracil (5-FU treatment. The goal of this study was to investigate the molecular and cellular impact of Orc6 in colon cancer. In this study, we use HCT116 (wt-p53 and HCT116 (null-p53 colon cancer cell lines as a model system to investigate the impact of Orc6 on cell proliferation, chemosensitivity and pathways involved with Orc6. We demonstrated that the down regulation of Orc6 sensitizes colon cancer cells to both 5-FU and cisplatin (cis-pt treatment. Decreased Orc6 expression in HCT-116 (wt-p53 cells by RNA interference triggered cell cycle arrest at G1 phase. Prolonged inhibition of Orc6 expression resulted in multinucleated cells in HCT-116 (wt-p53 cell line. Western immunoblot analysis showed that down regulation of Orc6 induced p21 expression in HCT-116 (wt-p53 cells. The induction of p21 was mediated by increased level of phosphorylated p53 at ser-15. By contrast, there is no elevated expression of p21 in HCT-116 (null-p53 cells. Orc6 down regulation also increased the expression of DNA damaging repair protein GADD45beta and reduced the expression level of JNK1. Orc6 may be a potential novel target for future anti cancer therapeutic development in colon cancer.

  6. Magnetic fluid hyperthermia enhances cytotoxicity of bortezomib in sensitive and resistant cancer cell lines.

    Science.gov (United States)

    Alvarez-Berríos, Merlis P; Castillo, Amalchi; Rinaldi, Carlos; Torres-Lugo, Madeline

    2014-01-01

    The proteasome inhibitor bortezomib (BZ) has shown promising results in some types of cancer, but in others it has had minimal activity. Recent studies have reported enhanced efficacy of BZ when combined with hyperthermia. However, the use of magnetic nanoparticles to induce hyperthermia in combination with BZ has not been reported. This novel hyperthermia modality has shown better potentiation of chemotherapeutics over other types of hyperthermia. We hypothesized that inducing hyperthermia via magnetic nanoparticles (MFH) would enhance the cytotoxicity of BZ in BZ-sensitive and BZ-resistant cancer cells more effectively than hyperthermia using a hot water bath (HWH). Studies were conducted using BZ in combination with MFH in two BZ-sensitive cell lines (MDA-MB-468, Caco-2), and one BZ-resistant cell line (A2780) at two different conditions, ie, 43°C for 30 minutes and 45°C for 30 minutes. These experiments were compared with combined application of HWH and BZ. The results indicate enhanced potentiation between hyperthermic treatment and BZ. MFH combined with BZ induced cytotoxicity in sensitive and resistant cell lines to a greater extent than HWH under the same treatment conditions. The observation that MFH sensitizes BZ-resistant cell lines makes this approach a potentially effective anticancer therapy platform.

  7. Pancreatic cancer cell lines deficient in argininosuccinate synthetase are sensitive to arginine deprivation by arginine deiminase.

    Science.gov (United States)

    Bowles, Tawnya L; Kim, Randie; Galante, Joseph; Parsons, Colin M; Virudachalam, Subbulakshmi; Kung, Hsing-Jien; Bold, Richard J

    2008-10-15

    Eukaryotic cells can synthesize the non-essential amino acid arginine from aspartate and citrulline using the enzyme argininosuccinate synthetase (ASS). It has been observed that ASS is underexpressed in various types of cancers ASS, for which arginine become auxotrophic. Arginine deiminase (ADI) is a prokaryotic enzyme that metabolizes arginine to citrulline and has been found to inhibit melanoma and hepatoma cancer cells deficient of ASS. We tested the hypothesis that pancreatic cancers have low ASS expression and therefore arginine deprivation by ADI will inhibit cell growth. ASS expression was examined in 47 malignant and 20 non-neoplastic pancreatic tissues as well as a panel of human pancreatic cancer cell lines. Arginine deprivation was achieved by treatment with a recombinant form of ADI formulated with polyethylene glycol (PEG-ADI). Effects on caspase activation, cell growth and cell death were examined. Furthermore, the effect of PEG-ADI on the in vivo growth of pancreatic xenografts was examined. Eighty-seven percent of the tumors lacked ASS expression; 5 of 7 cell lines similarly lacked ASS expression. PEG-ADI specifically inhibited growth of those cell lines lacking ASS. PEG-ADI treatment induced caspase activation and induction of apoptosis. PEG-ADI was well tolerated in mice despite complete elimination of plasma arginine; tumor growth was inhibited by approximately 50%. Reduced expression of ASS occurs in pancreatic cancer and predicts sensitivity to arginine deprivation achieved by PEG-ADI treatment. Therefore, these findings suggest that arginine deprivation by ADI could provide a beneficial strategy for the treatment of pancreatic cancer, a malignancy in which new therapy is desperately needed.

  8. Influence of Mesenchymal Stem Cells Conditioned Media on Proliferation of Urinary Tract Cancer Cell Lines and Their Sensitivity to Ciprofloxacin.

    Science.gov (United States)

    Maj, Malgorzata; Bajek, Anna; Nalejska, Ewelina; Porowinska, Dorota; Kloskowski, Tomasz; Gackowska, Lidia; Drewa, Tomasz

    2017-06-01

    Mesenchymal stem cells (MSCs) are known to interact with cancer cells through direct cell-to-cell contact and secretion of paracrine factors, although their exact influence on tumor progression in vivo remains unclear. To better understand how fetal and adult stem cells affect tumors, we analyzed viability of human renal (786-0) and bladder (T24) carcinoma cell lines cultured in conditioned media harvested from amniotic fluid-derived stem cells (AFSCs) and adipose-derived stem cells (ASCs). Both media reduced metabolic activity of 786-0 cells, however, decreased viability of T24 cells was noted only after incubation with conditioned medium from ASCs. To test the hypothesis that MSCs-secreted factors might be involved in chemoresistance acquisition, we further analyzed influence of mesenchymal stem cell conditioned media (MSC-CM) on cancer cells sensitivity to ciprofloxacin, that is considered as potential candidate agent for urinary tract cancers treatment. Significantly increased resistance to tested drug indicates that MSCs may protect cancer cells from chemotherapy. J. Cell. Biochem. 118: 1361-1368, 2017. © 2016 Wiley Periodicals, Inc.

  9. PES1 regulates sensitivity of colorectal cancer cells to anticancer drugs

    Energy Technology Data Exchange (ETDEWEB)

    Xie, Wei [Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Biochemistry and Molecular Biology, Peking University Cancer Hospital and Institute, Beijing 100142 (China); Qu, Like, E-mail: qulike@bjcancer.org [Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Biochemistry and Molecular Biology, Peking University Cancer Hospital and Institute, Beijing 100142 (China); Meng, Lin; Liu, Caiyun; Wu, Jian [Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Biochemistry and Molecular Biology, Peking University Cancer Hospital and Institute, Beijing 100142 (China); Shou, Chengchao, E-mail: scc@bjcancer.org [Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Biochemistry and Molecular Biology, Peking University Cancer Hospital and Institute, Beijing 100142 (China)

    2013-02-15

    Highlights: ► PES1 was overexpressed in diverse cancer cell lines. ► PES1-ablation enhances DNA damage response by decreasing DNA repair. ► PES1-ablation increases the sensitivity of HCT116 cells to chemotherapeutic agents. ► PES1-ablation is associated with diminished nuclear entry of RAD51. -- Abstract: PES1 (also known as Pescadillo), a nucleolar protein, was involved in biogenesis of ribosomal RNA. Up-regulation of PES1 has been documented in some human cancers, indicating that PES1 may play some crucial roles in tumorigenesis. In our previous study, it was found that silencing of PES1 resulted in decreased proliferation of colorectal cancer cells. We also noticed that depletion of PES1 altered expression profiles of diverse genes. In the present study, we validated the expression changes of a subset of genotoxic stress-related genes in PES1-silenced HCT116 cells by quantitative RT-PCR. The steady and etoposide-induced phosphorylated H2AX (γ-H2AX) were higher in PES1-silenced cells than in control cells. Besides, etoposide-induced γ-H2AX persisted longer in PES1-silenced cells after removing the etoposide. Next, results of comet assay revealed decreased DNA repair after PES1-ablation. PES1-ablated cells were more sensitive to chemotherapeutic agents, which could be reversed by reconstitution with exogenous PES1. Furthermore, deletion of PES1 diminished steady and DNA damage-induced levels of nuclear RAD51. Our results uncover a potential role of PES1 in chemoresistance by regulating DNA damage response in colorectal cancer cells.

  10. Differentially expressed proteins in human breast cancer cells sensitive and resistant to paclitaxel.

    Science.gov (United States)

    Pavlikova, Nela; Bartonova, Irena; Dincakova, Lucia; Halada, Petr; Kovar, Jan

    2014-08-01

    The resistance of cancer cells to chemotherapeutic drugs represents a major problem in cancer treatment. Despite all efforts, mechanisms of resistance have not yet been elucidated. To reveal proteins that could be involved in resistance to taxanes, we compared protein expression in whole cell lysates of SK-BR-3 breast cancer cells sensitive to paclitaxel and in lysates of the same line with acquired resistance to paclitaxel. The resistant SK-BR-3 cell line was established in our lab. Protein separation was achieved using high-resolution 2D-electrophoresis, computer analysis and mass spectro-metry. With these techniques we identified four proteins with different expression in resistant SK-BR-3 cells, i.e., serpin B3, serpin B4, heat shock protein 27 (all three upregulated) and cytokeratin 18 (downregulated). Observed changes were confirmed using western blot analysis. This study suggests new directions worthy of further study in the effort to reveal the mechanism of resistance to paclitaxel in breast cancer cells.

  11. Identification of eight genes that are potentially involved in tamoxifen sensitivity in breast cancer cells

    Institute of Scientific and Technical Information of China (English)

    Tyler ZARUBIN; Qing JING; Liguo NEW; Jiahuai HAN

    2005-01-01

    Although the antiestrogen agent tamoxifen has long been used to treat women with hormone receptor positive invasive breast carcinoma, the mechanisms of its action and acquired resistance to tamoxifen during treatment are largely unknown. A number of studies have revealed that over-activation of some signaling pathways can cause tamoxifen resistance; however, very little information is available regarding the genes whose loss-of-function alternation contribute to tamoxifen resistance. Here we used a forward genetic approach in vitro to generate tamoxifen resistant cells from the tamoxifen sensitive breast cancer cell line ZR-75-1, and further identified the disrupted gene in different tamoxifen resistant clones. Retinol binding protein 7, DNA polymerase-transactivated protein 3, γ-glutamyltransferase-like activity 1,slit-robo RhoGTPase-activating protein, tetraspan NET-4, HSPC 194, amiloride-sensitive epithelial sodium channel gene,and Notch2, were the eight mutated genes identified in different tamoxifen resistant clones, suggesting their requirement for tamoxifen sensitivity in ZR-75-1 cells. Since the functions of these genes are not related to each other, it suggests that multiple pathways can influence tamoxifen sensitivity in breast cancer cells.

  12. The natural flavonoid apigenin sensitizes human CD44(+) prostate cancer stem cells to cisplatin therapy.

    Science.gov (United States)

    Erdogan, Suat; Turkekul, Kader; Serttas, Rıza; Erdogan, Zeynep

    2017-04-01

    Prostate cancer (PCa) is the second most common type of cancer and the fifth leading cause of cancer-related death among men. Development of chemoresistance, tumor relapse and metastasis remain major barriers to effective treatment and all been identified to be associated with cancer stem cells (CSCs). Natural flavonoids such as apigenin have been shown to have the ability to improve the therapeutic efficacy of common chemotherapy agents through CSCs sensitization. Thus, the aim of this study was to evaluate the combination of apigenin with cisplatin on CD44(+) PCa stem cell growth and migration. Platinum-based anti-neoplastic drugs have been used to treat a number of malignancies including PCa. However, acquired resistance and side effects unfortunately have limited cisplatin's use. A CD44(+) subpopulation was isolated from human androgen-independent PC3 PCa cells by using human CD44-PE antibody. IC50 values were determined by MTT test. RT-qPCR, Western blot analyses and image-based cytometer were used to investigate apoptosis, cell cycle and their underlying molecular mechanisms. Cell migration was evaluated by wound healing test. The combination of the IC50 doses of apigenin (15μM) and cisplatin (7.5μM) for 48h significantly enhanced cisplatin's cytotoxic and apoptotic effects through downregulation of Bcl-2, sharpin and survivin; and upregulation of caspase-8, Apaf-1 and p53 mRNA expression. The combined therapy suppressed the phosphorylation of p-PI3K and p-Akt, inhibited the protein expression of NF-κB, and downregulated the cell cycle by upregulating p21, as well as cyclin dependent kinases CDK-2, -4, and -6. Apigenin significantly increased the inhibitory effects of cisplatin on cell migration via downregulation of Snail expression. In conclusion, our study showed the possible therapeutic approach of using apigenin to potentially increase the effects of cisplatin by targeting CSCs subset in prostate cancer.

  13. Nonlinear quantitative radiation sensitivity prediction model based on NCI-60 cancer cell lines.

    Science.gov (United States)

    Zhang, Chunying; Girard, Luc; Das, Amit; Chen, Sun; Zheng, Guangqiang; Song, Kai

    2014-01-01

    We proposed a nonlinear model to perform a novel quantitative radiation sensitivity prediction. We used the NCI-60 panel, which consists of nine different cancer types, as the platform to train our model. Important radiation therapy (RT) related genes were selected by significance analysis of microarrays (SAM). Orthogonal latent variables (LVs) were then extracted by the partial least squares (PLS) method as the new compressive input variables. Finally, support vector machine (SVM) regression model was trained with these LVs to predict the SF2 (the surviving fraction of cells after a radiation dose of 2 Gy γ-ray) values of the cell lines. Comparison with the published results showed significant improvement of the new method in various ways: (a) reducing the root mean square error (RMSE) of the radiation sensitivity prediction model from 0.20 to 0.011; and (b) improving prediction accuracy from 62% to 91%. To test the predictive performance of the gene signature, three different types of cancer patient datasets were used. Survival analysis across these different types of cancer patients strongly confirmed the clinical potential utility of the signature genes as a general prognosis platform. The gene regulatory network analysis identified six hub genes that are involved in canonical cancer pathways.

  14. Nonlinear Quantitative Radiation Sensitivity Prediction Model Based on NCI-60 Cancer Cell Lines

    Directory of Open Access Journals (Sweden)

    Chunying Zhang

    2014-01-01

    Full Text Available We proposed a nonlinear model to perform a novel quantitative radiation sensitivity prediction. We used the NCI-60 panel, which consists of nine different cancer types, as the platform to train our model. Important radiation therapy (RT related genes were selected by significance analysis of microarrays (SAM. Orthogonal latent variables (LVs were then extracted by the partial least squares (PLS method as the new compressive input variables. Finally, support vector machine (SVM regression model was trained with these LVs to predict the SF2 (the surviving fraction of cells after a radiation dose of 2 Gy γ-ray values of the cell lines. Comparison with the published results showed significant improvement of the new method in various ways: (a reducing the root mean square error (RMSE of the radiation sensitivity prediction model from 0.20 to 0.011; and (b improving prediction accuracy from 62% to 91%. To test the predictive performance of the gene signature, three different types of cancer patient datasets were used. Survival analysis across these different types of cancer patients strongly confirmed the clinical potential utility of the signature genes as a general prognosis platform. The gene regulatory network analysis identified six hub genes that are involved in canonical cancer pathways.

  15. S100A10 protein expression is associated with oxaliplatin sensitivity in human colorectal cancer cells

    Directory of Open Access Journals (Sweden)

    Suzuki Sayo

    2011-12-01

    Full Text Available Abstract Background Individual responses to oxaliplatin (L-OHP-based chemotherapy remain unpredictable. The objective of our study was to find candidate protein markers for tumor sensitivity to L-OHP from intracellular proteins of human colorectal cancer (CRC cell lines. We performed expression difference mapping (EDM analysis of whole cell lysates from 11 human CRC cell lines with different sensitivities to L-OHP by using surface-enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF MS, and identified a candidate protein by liquid chromatography/mass spectrometry ion trap time-of-flight (LCMS-IT-TOF. Results Of the qualified mass peaks obtained by EDM analysis, 41 proteins were differentially expressed in 11 human colorectal cancer cell lines. Among these proteins, the peak intensity of 11.1 kDa protein was strongly correlated with the L-OHP sensitivity (50% inhibitory concentrations (P R2 = 0.80. We identified this protein as Protein S100-A10 (S100A10 by MS/MS ion search using LCMS-IT-TOF. We verified its differential expression and the correlation between S100A10 protein expression levels in drug-untreated CRC cells and their L-OHP sensitivities by Western blot analyses. In addition, S100A10 protein expression levels were not correlated with sensitivity to 5-fluorouracil, suggesting that S100A10 is more specific to L-OHP than to 5-fluorouracil in CRC cells. S100A10 was detected in cell culture supernatant, suggesting secretion out of cells. Conclusions By proteomic approaches including SELDI technology, we have demonstrated that intracellular S100A10 protein expression levels in drug-untreated CRC cells differ according to cell lines and are significantly correlated with sensitivity of CRC cells to L-OHP exposure. Our findings provide a new clue to searching predictive markers of the response to L-OHP, suggesting that S100A10 is expected to be one of the candidate protein markers.

  16. siRNA-mediated downregulation of TC21 sensitizes esophageal cancer cells to cisplatin

    Institute of Scientific and Technical Information of China (English)

    Md.Raghibul Hasan; Shyam Singh Chauhan; Rinu Sharma; Ranju Ralhan

    2012-01-01

    AIM:To determine the functional significance of TC21 in esophageal squamous cell carcinoma (ESCC).METHODS:TC21 siRNA transfection was carried out using Hyperfectamine to knock down TC21,and transcripts were analyzed by reverse transcription-polymerase chain reaction and protein by Western blotting.We demonstrated the effect of TC21 downregulation of cell signaling in esophageal cancer cells by assessing the phosphorylation status of its downstream targets,phosphoinositide 3-kinase (PI3K),phosphatase and tensin homolog (PTEN),protein kinase B (pAkt),nuclear factor-κB (NF-κB) and cyclinD1 using specific antibodies.Cell survival analysis after cisplatin treatment was carried out by cell viability assay and cell cycle analysis using flow cytometry.RESULTS:TC21 knockdown in human ESCC cell line TE13 cells,showed only a marginal increase (14.2%) in cell death compared with control cells.The expressions of the signaling proteins PI3K and pAkt,transcription factor NF-κB,and cell cycle protein cyclin D1 were markedly decreased in response to TC21 downregulation,whereas the level of pPTEN,an antagonist of PI3K,was increased.In addition,we evaluated the potential of TC21 as a putative target for sensitizing ESCC cells to the chemotherapeutic agent dsplatin.Increased cell death (38.4%) was observed in cells treated with cisplatin after TC21 knockdown compared with cells which were treated with cisplatin alone (20% cell death).CONCLUSION:Results suggest that TC21 mediates its effects via the PI3K-Akt pathway,NF-κB and cydin D1,and enhances chemoresistance in esophageal cancer cells.

  17. Vitamin B₂ Sensitizes Cancer Cells to Vitamin-C-Induced Cell Death via Modulation of Akt and Bad Phosphorylation.

    Science.gov (United States)

    Chen, Ni; Yin, Shutao; Song, Xinhua; Fan, Lihong; Hu, Hongbo

    2015-08-01

    Vitamin C is an essential dietary nutrient that has a variety of biological functions. Recent studies have provided promising evidence for its additional health benefits, including anticancer activity. Vitamin B2, another essential dietary nutrient, often coexists with vitamin C in some fruits, vegetables, or dietary supplements. The objective of the present study is to determine whether the combination of vitamin C and B2 can achieve a synergistic anticancer activity. MDA-MB-231, MCF-7, and A549 cells were employed to evaluate the combinatory effects of vitamin C and B2. We found that the combination of vitamin C and B2 resulted in a synergistic cell death induction in all cell lines tested. Further mechanistic investigations revealed that vitamin B2 sensitized cancer cells to vitamin C through inhibition of Akt and Bad phosphorylation. Our findings identified vitamin B2 as a promising sensitizer for improving the efficacy of vitamin-C-based cancer chemoprevention and chemotherapy.

  18. Expression of cyclooxygenase-2 mRNA in drug-sensitive cell and drug-resistant strains of ovarian cancer cell lines

    Institute of Scientific and Technical Information of China (English)

    Xiaoyan Li; Zehua Wang

    2006-01-01

    Objective: To investigate the expression of cyclooxygenase-2 (COX-2) mRNA in drug-sensitive cell and drugresistant clones of ovarian cancer cell lines. Methods: RT-PCR and immunocytochemistry were used to investigate the expression of cyclooxygenase-2 in 3 clones drug-sensitive and 5 clones drug-resistant ovarian cancer cell. Results: Strong COX-2 mRNA expressions were detected in 3 clones of drug-sensitive cell and weak expressions were detected in 5 clones of drug-resistant cell. The protein expression of COX-2 in drug-sensitive cell was strongly positive reaction in immunocytochemistry stain and there was a weak positive reaction in 5clones of drug-resistant cell. Conclusion: The expression of COX-2 mRNA in drug-sensitive cell strains is much higher than that in drugresistant strains of ovarian cancer cell lines, providing a basis of the chemoprevention for ovarian cancer.

  19. Pharmacogenomics of Cisplatin Sensitivity in Non-small Cell Lung Cancer

    Institute of Scientific and Technical Information of China (English)

    Maimon C Rose; Elina Kostyanovskaya; R Stephanie Huang

    2014-01-01

    Cisplatin, a platinum-based chemotherapeutic drug, has been used for over 30 years in a wide variety of cancers with varying degrees of success. In particular, cisplatin has been used to treat late stage non-small cell lung cancer (NSCLC) as the standard of care. However, therapeutic outcomes vary from patient to patient. Considerable efforts have been invested to identify biomark-ers that can be used to predict cisplatin sensitivity in NSCLC. Here we reviewed current evidence for cisplatin sensitivity biomarkers in NSCLC. We focused on several key pathways, including nucleotide excision repair, drug transport and metabolism. Both expression and germline DNA variation were evaluated in these key pathways. Current evidence suggests that cisplatin-based treatment could be improved by the use of these biomarkers.

  20. Pharmacogenomics of Cisplatin Sensitivity in Non-small Cell Lung Cancer

    Directory of Open Access Journals (Sweden)

    Maimon C. Rose

    2014-10-01

    Full Text Available Cisplatin, a platinum-based chemotherapeutic drug, has been used for over 30 years in a wide variety of cancers with varying degrees of success. In particular, cisplatin has been used to treat late stage non-small cell lung cancer (NSCLC as the standard of care. However, therapeutic outcomes vary from patient to patient. Considerable efforts have been invested to identify biomarkers that can be used to predict cisplatin sensitivity in NSCLC. Here we reviewed current evidence for cisplatin sensitivity biomarkers in NSCLC. We focused on several key pathways, including nucleotide excision repair, drug transport and metabolism. Both expression and germline DNA variation were evaluated in these key pathways. Current evidence suggests that cisplatin-based treatment could be improved by the use of these biomarkers.

  1. Differentially expressed proteins in human MCF-7 breast cancer cells sensitive and resistant to paclitaxel.

    Science.gov (United States)

    Pavlíková, Nela; Bartoňová, Irena; Balušíková, Kamila; Kopperova, Dana; Halada, Petr; Kovář, Jan

    2015-04-10

    Resistance of cancer cells to chemotherapeutic agents is one of the main causes of treatment failure. In order to detect proteins potentially involved in the mechanism of resistance to taxanes, we assessed differences in protein expression in MCF-7 breast cancer cells that are sensitive to paclitaxel and in the same cells with acquired resistance to paclitaxel (established in our lab). Proteins were separated using two-dimensional electrophoresis. Changes in their expression were determined and proteins with altered expression were identified using mass spectrometry. Changes in their expression were confirmed using western blot analysis. With these techniques, we found three proteins expressed differently in resistant MCF-7 cells, i.e., thyroid hormone-interacting protein 6 (TRIP6; upregulated to 650%), heat shock protein 27 (HSP27; downregulated to 50%) and cathepsin D (downregulated to 28%). Silencing of TRIP6 expression by specific siRNA leads to decreased number of grown resistant MCF-7 cells. In the present study we have pointed at some new directions in the studies of the mechanism of resistance to paclitaxel in breast cancer cells.

  2. Synthetic Smac Peptide Enhances Chemo-sensitivity of Bladder Cancer Cells

    Institute of Scientific and Technical Information of China (English)

    Jing WANG; Fuqing ZENG; Liang WANG; Zhaohui ZHU; Guosong JIANG

    2008-01-01

    The effects of synthetic Smac peptide (SmacN7) on chemotherapeutic sensitivity of bladder cancer cells were investigated. SmacN7 penetratin peptide was synthesized and delivered into T24 cells. MTT assay was used to evaluate the viability of T24 cells induced by low-dosage of MMC. Flow cytometry was used to analyze the proportions of apoptosis. Western blot was used to detect the expression of XIAP and Caspase-3. The activity of Caspase-3 was measured and the effect of SmacN7 combined with MMC on T24 cell lines was also determined. The results showed that SmacN7 penetratin peptide could successfully interact with endogenous XIAP, increase the proportions of apoptosis of T24 cell lines induced by low-dosage of MMC in a dose-and time-dependent manner. An obvious down-regulation of XIAP expression and up-regulation of Caspase-3 was identified by Western blot. The activity of Caspase-3 in experimental group was significantly increased as compared with that in the control group. As compared with MMC group, the viability of T24 cells in SmacN7 penetratin peptide + MMC group was markedly decreased to 2.22 and 3.61 folds at 24h and 48h respectively. It was concluded that SmacN7 penetratin peptide could act as a cell-permeable IAP inhibitor, inhibit the proliferation, induce apoptosis and enhance the chemo-sensitivity of bladder cancer cells to MMC. These findings indicate that SmacN7 penetratin peptide may be a very promising ageut for bladder cancer treatment when used in combination with chemotherapy.

  3. Inhibition of PKM2 sensitizes triple-negative breast cancer cells to doxorubicin

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Feng [Department of Gastroenterology, The Tenth People’s Hospital of Shanghai, Tongji University, Shanghai 200072 (China); Department of Nanomedicine, Houston Methodist Research Institute, Houston, TX 77030 (United States); Yang, Yong, E-mail: yyang@houstonmethodist.org [Department of Nanomedicine, Houston Methodist Research Institute, Houston, TX 77030 (United States); Department of Medicine, Weill Cornell Medical College, New York, NY 10065 (United States)

    2014-11-21

    Highlights: • Suppression of PKM2 sensitizes triple-negative breast cancer cells to doxorubicin. • Repression of PKM2 affects the glycolysis and decreases ATP production. • Downregulation of PKM2 increases the intracellular accumulation of doxorubicin. • Inhibition of PKM2 enhances the antitumor efficacy of doxorubicin in vivo. - Abstract: Cancer cells alter regular metabolic pathways in order to sustain rapid proliferation. One example of metabolic remodeling in cancerous tissue is the upregulation of pyruvate kinase isoenzyme M2 (PKM2), which is involved in aerobic glycolysis. Indeed, PKM2 has previously been identified as a tumor biomarker and as a potential target for cancer therapy. Here, we examined the effects of combined treatment with doxorubicin and anti-PKM2 small interfering RNA (siRNA) on triple-negative breast cancer (TNBC). The suppression of PKM2 resulted in changes in glucose metabolism, leading to decreased synthesis of adenosine triphosphate (ATP). Reduced levels of ATP resulted in the intracellular accumulation of doxorubicin, consequently enhancing the therapeutic efficacy of this drug in several triple-negative breast cancer cell lines. Furthermore, the combined effect of PKM2 siRNA and doxorubicin was evaluated in an in vivo MDA-MB-231 orthotopic breast cancer model. The siRNA was systemically administered through a polyethylenimine (PEI)-based delivery system that has been extensively used. We demonstrate that the combination treatment showed superior anticancer efficacy as compared to doxorubicin alone. These findings suggest that targeting PKM2 can increase the efficacy of chemotherapy, potentially providing a new approach for improving the outcome of chemotherapy in patients with TNBC.

  4. Targeting Notch, a key pathway for ovarian cancer stem cells, sensitizes tumors to platinum therapy.

    Science.gov (United States)

    McAuliffe, Shannon M; Morgan, Stefanie L; Wyant, Gregory A; Tran, Lieu T; Muto, Katherine W; Chen, Yu Sarah; Chin, Kenneth T; Partridge, Justin C; Poole, Barish B; Cheng, Kuang-Hung; Daggett, John; Cullen, Kristen; Kantoff, Emily; Hasselbatt, Kathleen; Berkowitz, Julia; Muto, Michael G; Berkowitz, Ross S; Aster, Jon C; Matulonis, Ursula A; Dinulescu, Daniela M

    2012-10-23

    Chemoresistance to platinum therapy is a major obstacle that needs to be overcome in the treatment of ovarian cancer patients. The high rates and patterns of therapeutic failure seen in patients are consistent with a steady accumulation of drug-resistant cancer stem cells (CSCs). This study demonstrates that the Notch signaling pathway and Notch3 in particular are critical for the regulation of CSCs and tumor resistance to platinum. We show that Notch3 overexpression in tumor cells results in expansion of CSCs and increased platinum chemoresistance. In contrast, γ-secretase inhibitor (GSI), a Notch pathway inhibitor, depletes CSCs and increases tumor sensitivity to platinum. Similarly, a Notch3 siRNA knockdown increases the response to platinum therapy, further demonstrating that modulation of tumor chemosensitivity by GSI is Notch specific. Most importantly, the cisplatin/GSI combination is the only treatment that effectively eliminates both CSCs and the bulk of tumor cells, indicating that a dual combination targeting both populations is needed for tumor eradication. In addition, we found that the cisplatin/GSI combination therapy has a synergistic cytotoxic effect in Notch-dependent tumor cells by enhancing the DNA-damage response, G(2)/M cell-cycle arrest, and apoptosis. Based on these results, we conclude that targeting the Notch pathway could significantly increase tumor sensitivity to platinum therapy. Our study suggests important clinical applications for targeting Notch as part of novel treatment strategies upon diagnosis of ovarian cancer and at recurrence. Both platinum-resistant and platinum-sensitive relapses may benefit from such an approach as clinical data suggest that all relapses after platinum therapy are increasingly platinum resistant.

  5. Screening the Drug Sensitivity Genes Related to GEM and CDDP in the Lung Cancer Cell-lines

    Directory of Open Access Journals (Sweden)

    Chunyu YANG

    2009-10-01

    Full Text Available Background and objective Screening of small-cell lung cancer (SCLC and non-small cell lung cancer (NSCLC cell lines with gemcitabine hydrochloride (GEM and cisplatin (CDDP related to drug sensitivity gene might clarify the action mechanism of anti-cancer drugs and provide a new clue for overcoming drug resistance and the development of new anti-cancer drugs, and also provide theoretical basis for the clinical treatment of individual. Methods The drug sensitivity of CDDP and GEM in 4 SCLC cell lines and 6 NSCLC cell lines was determined using MTT colorimetric assay, while the cDNA macroarray was applied to detect the gene expression state related to drug sensitivity of 10 lung cancer cell line in 1 291, and the correlation between the two was analysized. Results There were 6 genes showing significant positive correlation (r≥0.632, P < 0.05 with GEM sensitivity; 45 genes positively related to CDDP; another 41 genes related to both GEM and CDDP (r≥± 0.4. Lung cancer with GEM and CDDP sensitivity of two types of drugs significantly related genes were Metallothinein (Signal transduction molecules, Cathepsin B (Organization protease B and TIMP1 (Growth factor; the GEM, CDDP sensitivity associated genes of lung cancer cell lines mainly distributed in Metallothinein, Cathepsin B, growth factor TIMP1 categories. Conclusion There existed drug-related sensitive genes of GEM, CDDP in SCLC and NSCLC cell lines; of these genes, Metallothinein, Cathepsin B and TIMP1 genes presented a significant positive correlation with GEM drug sensitivity, a significant negative correlation with CDDP drug sensitivity.

  6. Roscovitine sensitizes breast cancer cells to TRAIL-induced apoptosis through a pleiotropic mechanism

    Institute of Scientific and Technical Information of China (English)

    Gustavo Ortiz-Ferrón; Rosario Yerbes; Adriana Eramo; Ana I López-Pérez; Ruggero De Maria; Abelardo López-Rivas

    2008-01-01

    The tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL/APO2L) is a member of the TNF gene superfamily that induces apoptosis upon engagement of cognate death receptors.While TRAIL is relatively non-toxic to normal cells,it selectively induces apoptosis in many transformed cells.Nevertheless,breast tumor cells are particularly resistant to the effects of TRAIL.Here we report that,in combination with the cyclin-dependent kinase inhibitor roscovitine,exposure to TRAIL induced marked apoptosis in the majority of TRAIL-resistant breast cancer cell Iines examined.Roscovitine facilitated TRAIL death-inducing signaling complex formation and the activation of caspase-8.The cFLIPL and eFLIPs FLICE-inhibitory proteins were significantly down-regulated following exposure to roscovitine and,indeed,the knockdown of cFLIP isoforms by siRNA sensitized breast tumor cells to TRAIL-induced apoptosis.In addition,we demonstrate that roscovitine strongly suppressed Mcl-1 expression and up-regulated E2F1 protein levels in breast tumor cells.Significantly,the silencing of Mcl-1 by siRNA sensitized breast tumor cells to TRAIL-induced apoptosis.Furthermore,the knockdown of E2F1 protein by siRNA reduced the sensitizing effect of roscovitine in TRAIL-induced apoptosis.In summary,our results reveal a pleitropic mechanism for the pro-apoptotic influence of roscovitine,highlighting its potential as an antitumor agent in breast cancer in combination with TRAIL.

  7. Conserved features of cancer cells define their sensitivity to HAMLET-induced death; c-Myc and glycolysis.

    Science.gov (United States)

    Storm, P; Aits, S; Puthia, M K; Urbano, A; Northen, T; Powers, S; Bowen, B; Chao, Y; Reindl, W; Lee, D Y; Sullivan, N L; Zhang, J; Trulsson, M; Yang, H; Watson, J D; Svanborg, C

    2011-12-01

    HAMLET is the first member of a new family of tumoricidal protein-lipid complexes that kill cancer cells broadly, while sparing healthy, differentiated cells. Many and diverse tumor cell types are sensitive to the lethal effect, suggesting that HAMLET identifies and activates conserved death pathways in cancer cells. Here, we investigated the molecular basis for the difference in sensitivity between cancer cells and healthy cells. Using a combination of small-hairpin RNA (shRNA) inhibition, proteomic and metabolomic technology, we identified the c-Myc oncogene as one essential determinant of HAMLET sensitivity. Increased c-Myc expression levels promoted sensitivity to HAMLET and shRNA knockdown of c-Myc suppressed the lethal response, suggesting that oncogenic transformation with c-Myc creates a HAMLET-sensitive phenotype. Furthermore, HAMLET sensitivity was modified by the glycolytic state of tumor cells. Glucose deprivation sensitized tumor cells to HAMLET-induced cell death and in the shRNA screen, hexokinase 1 (HK1), 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 1 and hypoxia-inducible factor 1α modified HAMLET sensitivity. HK1 was shown to bind HAMLET in a protein array containing ∼8000 targets, and HK activity decreased within 15 min of HAMLET treatment, before morphological signs of tumor cell death. In parallel, HAMLET triggered rapid metabolic paralysis in carcinoma cells. Tumor cells were also shown to contain large amounts of oleic acid and its derivatives already after 15 min. The results identify HAMLET as a novel anti-cancer agent that kills tumor cells by exploiting unifying features of cancer cells such as oncogene addiction or the Warburg effect.

  8. Highly sensitive quantitative imaging for monitoring single cancer cell growth kinetics and drug response.

    Directory of Open Access Journals (Sweden)

    Mustafa Mir

    Full Text Available The detection and treatment of cancer has advanced significantly in the past several decades, with important improvements in our understanding of the fundamental molecular and genetic basis of the disease. Despite these advancements, drug-screening methodologies have remained essentially unchanged since the introduction of the in vitro human cell line screen in 1990. Although the existing methods provide information on the overall effects of compounds on cell viability, they are restricted by bulk measurements, large sample sizes, and lack capability to measure proliferation kinetics at the individual cell level. To truly understand the nature of cancer cell proliferation and to develop personalized adjuvant therapies, there is a need for new methodologies that provide quantitative information to monitor the effect of drugs on cell growth as well as morphological and phenotypic changes at the single cell level. Here we show that a quantitative phase imaging modality known as spatial light interference microscopy (SLIM addresses these needs and provides additional advantages over existing proliferation assays. We demonstrate these capabilities through measurements on the effects of the hormone estradiol and the antiestrogen ICI182,780 (Faslodex on the growth of MCF-7 breast cancer cells. Along with providing information on changes in the overall growth, SLIM provides additional biologically relevant information. For example, we find that exposure to estradiol results in rapidly growing cells with lower dry mass than the control population. Subsequently blocking the estrogen receptor with ICI results in slower growing cells, with lower dry masses than the control. This ability to measure changes in growth kinetics in response to environmental conditions provides new insight on growth regulation mechanisms. Our results establish the capabilities of SLIM as an advanced drug screening technology that provides information on changes in proliferation

  9. Colorectal cancer stem cell and chemoresistant colorectal cancer cell phenotypes and increased sensitivity to Notch pathway inhibitor.

    Science.gov (United States)

    Huang, Rui; Wang, Guiyu; Song, Yanni; Tang, Qingchao; You, Qi; Liu, Zheng; Chen, Yinggang; Zhang, Qian; Li, Jiaying; Muhammand, Shan; Wang, Xishan

    2015-08-01

    Colorectal cancer stem cells (Co-CSCs) are a small subpopulation of tumor cells which have been proposed to be tumor-initiating cells in colorectal cancer (CRC) and to be implicated in resistance to standard chemotherapy. Chemoresistance is a common problem in the clinic. However, the interrelation between Co-CSCs and chemoresistant cells has yet to be elucidated. The present study investigated the Co-CSC phenotype in colonospheres and chemoresistant CRC cell lines and aimed to identify targets for therapy. Colonospheres and chemoresistant CRC cells were found to be enriched with the CSC markers CD133 and CD44, and exhibited similar phenotypes. Furthermore, it was found that Notch signaling may simultaneously regulate Co-CSCs and chemoresistant cells and may represent a novel strategy for targeting this pathway in CRC.

  10. The EGFR family of receptors sensitizes cancer cells towards UV light

    Science.gov (United States)

    Petersen, Steffen; Neves-Petersen, Maria Teresa; Olsen, Birgitte

    2008-02-01

    A combination of bioinformatics, biophysical, advanced laser studies and cell biology lead to the realization that laser-pulsed UV light stops cancer growth and induces apoptosis. We have previously shown that laser-pulsed UV (LP-UV) illumination of two different skin-derived cancer cell lines both over expressing the EGF receptor, lead to arrest of the EGFR signaling pathway. We have investigated the available sequence and experimental 3D structures available in the Protein Data Bank. The EGF receptor contains a Furin like cystein rich extracellular domain. The cystein content is highly unusual, 25 disulphide bridges supports the 621 amino acid extracellular protein domain scaffold (1mb6.pdb). In two cases a tryptophan is neighboring a cystein in the primary sequence, which in itself is a rare observation. Aromatic residues is observed to be spatially close to all observed 25 disulphide bridges. The EGF receptor is often overexpressed in cancers and other proliferative skin disorders, it might be possible to significantly reduce the proliferative potential of these cells making them good targets for laser-pulsed UV-light treatment. The discovery that UV light can be used to open disulphide bridges in proteins upon illumination of nearby aromatic amino acids was the first step that lead to the hypothesis that UV light could modulate the structure and therefore the function of these key receptor proteins. The observation that membrane receptors (EGFR) contained exactly the motifs that are sensitive to UV light lead to the prediction that UV light could modify these receptors permanently and stop cancer proliferation. We hereby show that the EGFR family of receptors has the necessary structural motifs that make this family of proteins highly sensitive to UV light.

  11. Sensitive detection of cancer cells using light-mediated apta-PCR.

    Science.gov (United States)

    Civit, Laia; Pinto, Alessandro; Rodrigues-Correia, Alexandre; Heckel, Alexander; O'Sullivan, Ciara K; Mayer, Günter

    2016-03-15

    Apta-PCR is an ultrasensitive assay in which aptamers are exploited not only as biomolecular recognition elements, but also as reporter labels for amplification via real-time PCR. This methodology has been successfully applied to the detection of proteins, achieving limits of detection in the picomolar range. The introduction of caged aptamers that bear photo-labile groups, so called cages, at strategic positions so that their tertiary structure and thus their binding properties can be controlled by light, facilitates a more robust and attractive assay in terms of sample conservation and reusability. In this work, we report for the first time the use of caged aptamers for cell detection in an apta-PCR assay. Specifically, a sandwich format is used combining the capture of B-cells by an antibody with the specific detection of Burkitt's lymphoma cancer cells by a caged aptamer, acting as a reporter probe. Elution of the aptamer bound to the cancer cells is performed by light and the number of cells is then correlated with the amount of eluted caged aptamer using real-time PCR analysis. The reported technique shows an excellent sensitivity, achieving detection of as few as 77 cells, and due to the inherent robustness of the assay, this detection platform can be reused for further analyses, demonstrating potential applicability in proteomics and clinical diagnostics.

  12. An Epigenetic Pathway Regulates Sensitivity of Breast Cancer Cells to HER2 Inhibition via FOXO/c-Myc Axis

    Science.gov (United States)

    Matkar, Smita; Sharma, Paras; Gao, Shubin; Gurung, Buddha; Katona, Bryson W; Liao, Jennifer; Muhammad, Abdul Bari; Kong, Xiang-Cheng; Wang, Lei; Jin, Guanghui; Dang, Chi; Hua, Xianxin

    2016-01-01

    SUMMARY Human epidermal growth factor receptor 2 (HER2) is upregulated in a subset of human breast cancers. However, the cancer cells often quickly develop an adaptive response to HER2 kinase inhibitors. We found that an epigenetic pathway involving MLL2 is crucial for growth of HER2+ cells and MLL2 reduces sensitivity of the cancer cells to a HER2 inhibitor, Lapatinib. Lapatinib-induced FOXO transcription factors, normally tumor-suppressing, paradoxically upregulate c-Myc epigenetically, in concert with a cascade of MLL2-associating epigenetic regulators, to dampen sensitivity of the cancer cells to Lapatinib. An epigenetic inhibitor suppressing c-Myc synergizes with Lapatinib to suppress cancer growth in vivo, partly by repressing the FOXO/c-Myc axis, unraveling an epigenetically regulated FOXO/c-Myc axis as a potential target to improve therapy. PMID:26461093

  13. Glutamine deprivation sensitizes human breast cancer MDA-MB-231 cells to TRIAL-mediated apoptosis.

    Science.gov (United States)

    Dilshara, Matharage Gayani; Jeong, Jin-Woo; Prasad Tharanga Jayasooriya, Rajapaksha Gedara; Neelaka Molagoda, Ilandarage Menu; Lee, Seungheon; Park, Sang Rul; Choi, Yung Hyun; Kim, Gi-Young

    2017-02-13

    Tumor cell metabolism is a promising target for various cancer treatments. Apart from aerobic glycolysis, cancer cell growth is dependent on glutamine (Gln) supply, leading to their survival and differentiation. Therefore, we examined whether treatment with TNF-related apoptosis-inducing ligand (TRAIL) sensitizes MDA-MB-231 cells to apoptosis under Gln deprivation condition (TRAIL/Gln deprivation). Gln deprivation decreased cell proliferation as expected, but did not induce remarkable cell death. TRAIL/Gln deprivation, however, significantly increased growth inhibition and morphological shrinkage of MDA-MB-231 cells compared to those induced by treatment with either Gln deprivation or TRAIL alone. Moreover, TRAIL/Gln deprivation upregulated the apoptotic sub-G1 phase accompanied with a remarkable decrease of pro-caspase-3, pro-caspase-9, and anti-apoptotic xIAP, and Bcl-2. Increased cleavage of PARP and pro-apoptotic Bid protein expression suggests that TRAIL/Gln deprivation triggers mitochondrion-mediated apoptosis in MDA-MB-231 cells. Additionally, TRAIL/Gln deprivation upregulated the expression of endoplasmic reticulum (ER) stress markers such as ATF4 and phosphorylated eIF2α, thereby enhancing the C/EBP homologous protein (CHOP) protein level. Transient knockdown of CHOP partically reversed TRAIL/Gln deprivation-mediated apoptosis. Accordingly, TRAIL/Gln deprivation enhanced the expression of death receptor 5 (DR5) and transient knockdown of DR5 completely restored TRAIL/Gln deprivation-mediated apoptosis. Taken together, our results suggest that Gln deprivation conditions can be used for the development of new therapies for TRAIL-resistant cancers.

  14. Risk group, skin lesion history, and sun sensitivity reliability in squamous cell skin cancer progression.

    Science.gov (United States)

    Clouser, Mary C; Harris, Robin B; Roe, Denise J; Saboda, Kathylynn; Ranger-Moore, James; Duckett, Laura; Alberts, David S

    2006-11-01

    In studies of skin cancer, participants are often classified into risk groups based on self-reported history of sun exposure or skin characteristics. We sought to determine the reliability of self-reported skin characteristics among participants of a study to evaluate markers for nonmelanoma skin cancer (NMSC). Multiple questionnaires and screening protocols were administered over a 3-month period to individuals from three risk groups: existing sun damage on forearms but no visible actinic keratoses (n = 91), visible actinic keratoses (n = 38), and history of resected squamous cell skin cancer in the last 12 months (n = 35). We assessed consistency of risk group assignment between telephone screen and study dermatologist assignment, self-reported sun sensitivity (telephone recruitment form versus participant completed profile), and self-reported history of NMSC skin lesions (telephone recruitment form versus health history). There was substantial agreement between probable risk group and final assignment (kappa = 0.76; 95% confidence interval, 0.65-0.85) and agreement did not differ by gender. Agreement for self-reported sun sensitivity was moderate (kappa weighted = 0.46; 95% confidence interval, 0.36-0.56) with higher agreement for women. For self-reported NMSC lesion history between two interviews, 24 days apart, kappa estimates ranged from 0.66 to 0.78 and were higher for women than men. Overall, there was evidence for substantial reproducibility related to risk group assignment and self-reported history of NMSC, with self-reported sun sensitivity being less reliable. In all comparisons, women had higher kappa values than men. These results suggest that self-reported measures of skin cancer risk are reasonably reliable for use in screening subjects into studies.

  15. YAP Inhibition by Resveratrol via Activation of AMPK Enhances the Sensitivity of Pancreatic Cancer Cells to Gemcitabine

    Directory of Open Access Journals (Sweden)

    Zhengdong Jiang

    2016-09-01

    Full Text Available Resveratrol, a natural polyphenol present in most plants, inhibits the growth of numerous cancers both in vitro and in vivo. Aberrant expression of YAP has been reported to activate multiple growth-regulatory pathways and confer anti-apoptotic abilities to many cancer cells. However, the role of resveratrol in YES-activated protein (YAP expression and that of YAP in pancreatic cancer cells’ response to gemcitabine resistance remain elusive. In this study, we found that resveratrol suppressed the proliferation and cloning ability and induced the apoptosis of pancreatic cancer cells. These multiple biological effects might result from the activation of AMP-activation protein kinase (AMPK (Thr172 and, thus, the induction of YAP cytoplasmic retention, Ser127 phosphorylation, and the inhibition of YAP transcriptional activity by resveratrol. YAP silencing by siRNA or resveratrol enhanced the sensitivity of gemcitabine in pancreatic cancer cells. Taken together, these findings demonstrate that resveratrol could increase the sensitivity of pancreatic cancer cells to gemcitabine by inhibiting YAP expression. More importantly, our work reveals that resveratrol is a potential anticancer agent for the treatment of pancreatic cancer, and YAP may serve as a promising target for sensitizing pancreatic cancer cells to chemotherapy.

  16. Afatinib increases sensitivity to radiation in non-small cell lung cancer cells with acquired EGFR T790M mutation.

    Science.gov (United States)

    Zhang, Shirong; Zheng, Xiaoliang; Huang, Haixiu; Wu, Kan; Wang, Bing; Chen, Xufeng; Ma, Shenglin

    2015-03-20

    Afatinib is a second-generation of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor and has shown a significant clinical benefit in non-small cell lung cancer (NSCLC) patients with EGFR-activating mutations. However, the potential therapeutic effects of afatinib combining with other modalities, including ionizing radiation (IR), are not well understood. In this study, we developed a gefitinib-resistant cell subline (PC-9-GR) with a secondary EGFR mutation (T790M) from NSCLC PC-9 cells after chronic exposures to increasing doses of gefitinib. The presence of afatinib significantly increases the cell killing effect of radiation in PC-9-GR cells harboring acquired T790M, but not in H1975 cells with de novo T790M or in H460 cells that express wild-type EGFR. In PC-9-GR cells, afatinib remarkable blocks baseline of EGFR and ERK phosphorylations, and causes delay of IR-induced AKT phosphorylation. Afatinib treatment also leads to increased apoptosis and suppressed DNA damage repair in irradiated PC-9-GR cells, and enhanced tumor growth inhibition when combined with IR in PC-9-GR xenografts. Our findings suggest a potential therapeutic impact of afatinib as a radiation sensitizer in lung cancer cells harboring acquired T790M mutation, providing a rationale for a clinical trial with combination of afatinib and radiation in NSCLCs with EGFR T790M mutation.

  17. Inhibition of c-Abl kinase activity renders cancer cells highly sensitive to mitoxantrone.

    Directory of Open Access Journals (Sweden)

    Kemal Alpay

    Full Text Available Although c-Abl has increasingly emerged as a key player in the DNA damage response, its role in this context is far from clear. We studied the effect of inhibition of c-Abl kinase activity by imatinib with chemotherapy drugs and found a striking difference in cell survival after combined mitoxantrone (MX and imatinib treatment compared to a panel of other chemotherapy drugs. The combinatory treatment induced apoptosis in HeLa cells and other cancer cell lines but not in primary fibroblasts. The difference in MX and doxorubicin was related to significant augmentation of DNA damage. Transcriptionally active p53 accumulated in cells in which human papillomavirus E6 normally degrades p53. The combination treatment resulted in caspase activation and apoptosis, but this effect did not depend on either p53 or p73 activity. Despite increased p53 activity, the cells arrested in G2 phase became defective in this checkpoint, allowing cell cycle progression. The effect after MX treatment depended partially on c-Abl: Short interfering RNA knockdown of c-Abl rendered HeLa cells less sensitive to MX. The effect of imatinib was decreased by c-Abl siRNA suggesting a role for catalytically inactive c-Abl in the death cascade. These findings indicate that MX has a unique cytotoxic effect when the kinase activity of c-Abl is inhibited. The treatment results in increased DNA damage and c-Abl-dependent apoptosis, which may offer new possibilities for potentiation of cancer chemotherapy.

  18. Detecting the effect of targeted anti-cancer medicines on single cancer cells using a poly-silicon wire ion sensor integrated with a confined sensitive window.

    Science.gov (United States)

    Wu, You-Lin; Hsu, Po-Yen; Hsu, Chung-Ping; Lin, Jing-Jenn

    2012-10-01

    A mold-cast polydimethylsiloxane (PDMS) confined window was integrated with a poly-silicon wire (PSW) ion sensor. The PSW sensor surface inside the confined window was coated with a 3-aminopropyltriethoxysilane (γ-APTES) sensitive layer which allowed a single living cell to be cultivated. The change in the microenvironment due to the extracellular acidification of the single cell could then be determined by measuring the current flowing through the PSW channel. Based on this, the PSW sensor integrated with a confined sensitive window was used to detect the apoptosis as well as the effect of anti-cancer medicines on the single living non-small-lung-cancer (NSLC) cells including lung adenocarcinoma cancer cells A549 and H1299, and lung squamous-cell carcinoma CH27 cultivated inside the confined window. Single human normal cells including lung fibroblast cells WI38, lung fibroblast cells MRC5, and bronchial epithelium cell Beas-2B were tested for comparison. Two targeted anti-NSCLC cancer medicines, Iressa and Staurosporine, were used in the present study. It was found that the PSW sensor can be used to accurately detect the apoptosis of single cancer cells after the anti-cancer medicines were added. It was also found that Staurosporine is more effective than Iressa in activating the apoptosis of cancer cells.

  19. Zerumbone inhibits growth of hormone refractory prostate cancer cells by inhibiting JAK2/STAT3 pathway and increases paclitaxel sensitivity.

    Science.gov (United States)

    Jorvig, Jessica E; Chakraborty, Arup

    2015-02-01

    Zerumbone, a phytochemical isolated from Zingiber zerumbet has been shown previously to exhibit antineoplastic activity. But, the effect of zerumbone in prostate cancer has not been evaluated. Prostate cancer is frequently associated with elevated levels of interleukin-6 (IL-6), which exerts its oncogenic effects through activation of Janus kinase 2 (JAK2) followed by activation of the transcription factor STAT3 (signal transducer and activator of transcription 3). Here, we investigated whether the anticancer effects of zerumbone are mediated through inhibition of the JAK2/STAT3 signaling pathway and whether zerumbone can increase the paclitaxel (PTX) sensitivity of prostate cancer cells. Zerumbone exerted significant cytotoxicity of DU145 versus PC3 prostate cancer cells through cell cycle arrest at G0/G1 phase followed by apoptosis. Zerumbone selectively inhibited JAK2 in both DU145 and PC3 cells. However, the biological axis of IL-6/JAK2/STAT3 was inhibited only in DU145 cells as no STAT3 phosphorylation was detected in PC3 cells even after IL-6 stimulation. Other signaling pathways in DU145 cells remained unaffected. The expression of prostate cancer-associated genes, including cyclin D1, IL-6, COX2, and ETV1, was blocked. Zerumbone also synergistically increased the sensitivity to PTX. Further preclinical study might reveal the potential use of zerumbone as a chemotherapeutic agent for hormone refractory prostate cancer where IL-6/JAK2/STAT3 signaling is aberrantly active and may be combined with PTX.

  20. Inhibition of Autophagy by Deguelin Sensitizes Pancreatic Cancer Cells to Doxorubicin

    Science.gov (United States)

    Xu, Xiao Dong; Zhao, Yan; Zhang, Min; He, Rui Zhi; Shi, Xiu Hui; Guo, Xing Jun; Shi, Cheng Jian; Peng, Feng; Wang, Min; Shen, Min; Wang, Xin; Li, Xu; Qin, Ren Yi

    2017-01-01

    Pancreatic cancer is the fourth most common cause of cancer mortality worldwide. Furthermore, patients with pancreatic cancer experience limited benefit from current chemotherapeutic approaches because of drug resistance. Therefore, an effective therapeutic strategy for patients with pancreatic cancer is urgently required. Deguelin is a natural chemopreventive drug that exerts potent antiproliferative activity in solid tumors by inducing cell death. However, the molecular mechanisms underlying this activity have not been fully elucidated. Here we show that deguelin blocks autophagy and induces apoptosis in pancreatic cancer cells in vitro. Autophagy induced by doxorubicin plays a protective role in pancreatic cancer cells, and suppressing autophagy by chloroquine or silencing autophagy protein 5 enhanced doxorubicin-induced cell death. Similarly, inhibition of autophagy by deguelin also chemosensitized pancreatic cancer cell lines to doxorubicin. These findings suggest that deguelin has potent anticancer effects against pancreatic cancer and potentiates the anti-cancer effects of doxorubicin. These findings provide evidence that combined treatment with deguelin and doxorubicin represents an effective strategy for treating pancreatic cancer. PMID:28208617

  1. Pancreatic cancer cell lines deficient in argininosuccinate synthetase are sensitive to arginine deprivation by arginine deiminase

    OpenAIRE

    Bowles, Tawnya L.; Kim, Randie; Galante, Joseph; Parsons, Colin M.; Virudachalam, Subbulakshmi; Kung, Hsing-Jien; Bold, Richard J.

    2008-01-01

    Eukaryotic cells can synthesize the non-essential amino acid arginine from aspartate and citrulline using the enzyme argininosuccinate synthetase (ASS). It has been observed that ASS is under-expressed in various types of cancers ASS, for which arginine become auxotrophic. Arginine deiminase (ADI) is a prokaryotic enzyme that metabolizes arginine to citrulline and has been found to inhibit melanoma and hepatoma cancer cells deficient of ASS. We tested the hypothesis that pancreatic cancers ha...

  2. 30. Knockdown of IGF-IR by Antisense Oligodeoxynucleotide auguments the sensitivity of bladder cancer cells to MMC

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    AND AIM: Transitional cell carcinoma (TCC) of the bladder represents the fifth most prevalent malignancy in Western population, with peak incidence found in males of the 50-to 70- year-old age group. A major problem in the management of bladder cancer is the low sensitivity of a large proportion (approximately 40%) among bladder tumors to chemotherapy and the high risk for recurrence of bladder tumors after transurethral resection. So drug resistance, especially in its multiple type forms, remains a major and difficult problem to resolve in bladder cancer therapy. This phenomenon has often been ascribed to strictly pharmacolo-gic factors, such as the overexpression of multidrug transporters P-glycoprotein, multidrug resistance related protein (MRP), and other variables closely implicated DNA repair and induction/modulation of apoptosis, such as P53 and the Bcl-protein family. Furthermore, it has been recently shown that certain growth factors(IGFs etc) may be involved in the mechanism of drug resistance. Clearly, these findings suggest the design of new strategies that might improve bladder tumor response to chemotherapy. Results have previously shown that human bladder tumor cell lines may be adapted to grow in the complete absence of serum or any other growth supplement and that this can be explained on the basis of autocrine stimulation. The acquirement of autonomous growth capacity was likely to be an important element in the oncogenesis of bladder tumors. Furthermore, criss-cross experiments showed that supernatants stimulated not only proliferation of the autologous cell line of bladder cancer, but also growth of the other bladder cancer cell lines, suggesting the production of common autocrine factors in bladder tumor cells. Some factors or their receptors involved in autocrine loop mechanism of bladder tumor cells have been confirmed, such as IL-6, the epidermal growth factor receptor, IFN-beta, transferrins-like substance etc. But certain factors which may

  3. Targeting Breast Cancer Recurrence via Hedgehog-Mediated Sensitization of Breast Cancer Stem Cells

    Science.gov (United States)

    2012-07-01

    epithelium is carried out via symmetric mitosis that is parallel to the outer surface of the sphere. By contrast the elaboration and expansion of...Nature  439,  84  (Jan  5,  2006).   12.   J.  Debnath,  J.  S.  Brugge,  Modelling   glandular  epithelial  cancers  in

  4. Effects of stathmin 1 silencing by siRNA on sensitivity of esophageal cancer cells Eca-109 to paclitaxel.

    Science.gov (United States)

    Zhu, H W; Jiang, D; Xie, Z Y; Zhou, M H; Sun, D Y; Zhao, Y G

    2015-12-29

    We investigated the effects of stathmin 1 (STMN1) silencing by small interfering (siRNA) on the sensitivity of esophageal cancer cells Eca-109 to paclitaxel. STMN1 siRNA was transiently transfected into Eca-109 cells. The effects of transfection were detected by quantitative polymerase chain reaction and western blotting. The effects of STMN1 silencing by siRNA on the sensitivity of esophageal cancer cells Eca-109 to paclitaxel was tested by MTT and colony formation assays. Hoechst 33258 nuclear staining was used to investigate the differences in Eca-109 cell apoptosis induced by paclitaxel. STMN1 siRNA was successfully transfected and the expression of STMN1 was inhibited. The sensitivity of STMN1 siRNA-transfected Eca-109 cells to paclitaxel was significantly increased (P < 0.01). The apoptosis of Eca-109 cells significantly increased following treatment with paclitaxel (P < 0.01). STMN1 silencing by siRNA may enhance the sensitivity of esophageal cancer cells Eca-109 to paclitaxel and induce apoptosis.

  5. RNA interference of argininosuccinate synthetase restores sensitivity to recombinant arginine deiminase (rADI in resistant cancer cells

    Directory of Open Access Journals (Sweden)

    Yo Hao-Hsin

    2011-04-01

    Full Text Available Abstract Background Sensitivity of cancer cells to recombinant arginine deiminase (rADI depends on expression of argininosuccinate synthetase (AS, a rate-limiting enzyme in synthesis of arginine from citrulline. To understand the efficiency of RNA interfering of AS in sensitizing the resistant cancer cells to rADI, the down regulation of AS transiently and permanently were performed in vitro, respectively. Methods We studied the use of down-regulation of this enzyme by RNA interference in three human cancer cell lines (A375, HeLa, and MCF-7 as a way to restore sensitivity to rADI in resistant cells. The expression of AS at levels of mRNA and protein was determined to understand the effect of RNA interference. Cell viability, cell cycle, and possible mechanism of the restore sensitivity of AS RNA interference in rADI treated cancer cells were evaluated. Results AS DNA was present in all cancer cell lines studied, however, the expression of this enzyme at the mRNA and protein level was different. In two rADI-resistant cell lines, one with endogenous AS expression (MCF-7 cells and one with induced AS expression (HeLa cells, AS small interference RNA (siRNA inhibited 37-46% of the expression of AS in MCF-7 cells. ASsiRNA did not affect cell viability in MCF-7 which may be due to the certain amount of residual AS protein. In contrast, ASsiRNA down-regulated almost all AS expression in HeLa cells and caused cell death after rADI treatment. Permanently down-regulated AS expression by short hairpin RNA (shRNA made MCF-7 cells become sensitive to rADI via the inhibition of 4E-BP1-regulated mTOR signaling pathway. Conclusions Our results demonstrate that rADI-resistance can be altered via AS RNA interference. Although transient enzyme down-regulation (siRNA did not affect cell viability in MCF-7 cells, permanent down-regulation (shRNA overcame the problem of rADI-resistance due to the more efficiency in AS silencing.

  6. Targeting Breast Cancer Recurrence via Hedgehog-mediated Sensitization of Breast Cancer Stem Cells

    Science.gov (United States)

    2011-07-01

    mammary stem cell from wt mice and Ptch1+/- to give rise to luminal, myoepithelial or mixed colonies. MECs were isolated and cultured under low...attachment conditions and the resulting mammospheres disaggregated and plated at clonogenic density for 8 days, then stained for luminal and myoepithelial ...cells compare to wt was observed. The decrease in the number of myoepithelial cells in the heterozygous mice is also in accordance with the role

  7. Human cancer cells with stem cell-like phenotype exhibit enhanced sensitivity to the cytotoxicity of IL-2 and IL-15 activated natural killer cells.

    Science.gov (United States)

    Yin, Tao; Wang, Guoping; He, Sisi; Liu, Qin; Sun, Jianhong; Wang, Yongsheng

    2016-02-01

    Tumors harbor a population of cancer stem cells (CSCs) which can drive tumor progression and therapeutical resistance. Nature killer (NK) cells are best known for their ability to directly recognize and kill malignant cells. However, the susceptibility of cancer stem cells to NK cells is not fully understood. Here we demonstrated that human CD44+CD24- breast CSCs were shown enhanced sensitivity to IL-2 and IL-15 activated NK cells. CD44+CD24- CSCs expressed higher levels of NKG2D ligands ULBP1, ULBP2 and MICA. Blockade assay showed that the sensitivity of CSCs to NK cells-mediated lysis was mainly dependent on NKG2D. Furthermore, redox oxygen species (ROS)-low tumor cells were more sensitive to NK cells. The presence of antioxidant enzymes inhibitor L-S,R-buthionine sulfoximine or H2O2 retarded the cytotoxicity of NK cells to CD44+CD24- CSCs. In addition, NK cells could readily target CD133+ colonal CSCs. Our findings provide novel targets for NK cells-based immunotherapy and are of great importance for translational medicine.

  8. MEK5/ERK5 signaling inhibition increases colon cancer cell sensitivity to 5-fluorouracil through a p53-dependent mechanism

    Science.gov (United States)

    Pereira, Diane M.; Simões, André E. S.; Gomes, Sofia E.; Castro, Rui E.; Carvalho, Tânia; Rodrigues, Cecília M. P.; Borralho, Pedro M.

    2016-01-01

    The MEK5/ERK5 signaling pathway is emerging as an important contributor to colon cancer onset, progression and metastasis; however, its relevance to chemotherapy resistance remains unknown. Here, we evaluated the impact of the MEK5/ERK5 cascade in colon cancer cell sensitivity to 5-fluorouracil (5-FU). Increased ERK5 expression was correlated with poor overall survival in colon cancer patients. In colon cancer cells, 5-FU exposure impaired endogenous KRAS/MEK5/ERK5 expression and/or activation. In turn, MEK5 constitutive activation reduced 5-FU-induced cytotoxicity. Using genetic and pharmacological approaches, we showed that ERK5 inhibition increased caspase-3/7 activity and apoptosis following 5-FU exposure. Mechanistically, this was further associated with increased p53 transcriptional activation of p21 and PUMA. In addition, ERK5 inhibition increased the response of HCT116 p53+/+ cells to 5-FU, but failed to sensitize HCT116 p53−/− cells to the cytotoxic effects of this chemotherapeutic agent, suggesting a p53-dependent axis mediating 5-FU sensitization. Finally, ERK5 inhibition using XMD8-92 was shown to increase the antitumor effects of 5-FU in a murine subcutaneous xenograft model, enhancing apoptosis while markedly reducing tumor growth. Collectively, our results suggest that ERK5-targeted in hibition provides a promising therapeutic approach to overcome resistance to 5-FU-based chemotherapy and improve colon cancer treatment. PMID:27144434

  9. Ursolic acid sensitized colon cancer cells to chemotherapy under hypoxia by inhibiting MDR1 through HIF-1α*

    Science.gov (United States)

    Shan, Jian-zhen; Xuan, Yan-yan; Zhang, Qi; Huang, Jian-jin

    2016-01-01

    Objective: To explore the efficacy of ursolic acid in sensitizing colon cancer cells to chemotherapy under hypoxia and its underlying mechanisms. Methods: Three colon cancer cell lines (RKO, LoVo, and SW480) were used as in vitro models. 5-Fluorouracil (5-FU) and oxaliplatin were used as chemotherapeutic drugs. Cell viability and apoptosis were tested to evaluate the sensitivity of colon cancer cells to chemotherapy. The transcription and expression levels of hypoxia-inducible factor-1α (HIF-1α), multidrug resistance gene 1 (MDR1), and vascular endothelial growth factors (VEGF) were assessed by quantitative real-time polymerase chain reaction (qRT-PCR) and immunoblotting. Cycloheximide and MG132 were used to inhibit protein synthesis and degradation, respectively. In vitro tube formation assay was used to evaluate angiogenesis. Results: We demonstrated the chemosensitizing effects of ursolic acid with 5-FU and oxaliplatin in three colon cancer cell lines under hypoxia. This effect was correlated to its inhibition of MDR1 through HIF-1α. Moreover, ursolic acid was capable of inhibiting HIF-1α accumulation with little effects on its constitutional expression in normoxia. In addition, ursolic acid also down-regulated VEGF and inhibited tumor angiogenesis. Conclusions: Ursolic acid exerted chemosensitizing effects in colon cancer cells under hypoxia by inhibiting HIF-1α accumulation and the subsequent expression of the MDR1 and VEGF. PMID:27604859

  10. Identification of the determinants of 2-deoxyglucose sensitivity in cancer cells by shRNA library screening.

    Science.gov (United States)

    Kobayashi, Hiroki; Nishimura, Haruna; Matsumoto, Ken; Yoshida, Minoru

    2015-11-06

    Combining glycolytic inhibition with other anti-cancer therapies is a potential approach to treating cancer. In this context, we attempted to identify genes that determine sensitivity to 2-deoxyglucose (2DG), a glycolytic inhibitor, in cancer cells using pooled shRNA libraries targeting ∼15,000 genes. The screen revealed that COPB1 and ARCN1, which are essential in retrograde transport, as determinants of sensitivity to 2DG: silencing of COPB1 or ARCN1 expression sensitized cells to 2DG toxicity. To address the mechanism of potentiation of 2DG toxicity by inhibition of COPI-mediated transport, we focused on the role of lipolysis as an alternate source of energy upon inhibition of glycolysis. In the process of lipolysis, COPI-mediated transport is required for localization to lipid droplets of adipose triglyceride lipase (ATGL), a key enzyme that produces fatty acids from triacylglycerol as a substrate for β-oxidation. The ATGL inhibitor atglistatin potentiated 2DG toxicity, consistent with a model in which a defect in COPI-mediated transport of ATGL to lipid droplets inhibits energy supply, thereby sensitizing cells to glycolytic inhibition. Collectively, our data demonstrated that a defect in COPI-mediated transport or pharmacological inhibition of ATGL potentiates 2DG toxicity in cancer cells, possibly due to a reduction in the energy supply.

  11. High specificity but low sensitivity of mutation-specific antibodies against EGFR mutations in non-small-cell lung cancer

    DEFF Research Database (Denmark)

    Bondgaard, Anna-Louise; Høgdall, Estrid; Mellemgaard, Anders;

    2014-01-01

    Determination of epidermal growth factor receptor (EGFR) mutations has a pivotal impact on treatment of non-small-cell lung cancer (NSCLC). A standardized test has not yet been approved. So far, Sanger DNA sequencing has been widely used. Its rather low sensitivity has led to the development...

  12. Breast cancer stem cells rely on fermentative glycolysis and are sensitive to 2-deoxyglucose treatment.

    Science.gov (United States)

    Ciavardelli, D; Rossi, C; Barcaroli, D; Volpe, S; Consalvo, A; Zucchelli, M; De Cola, A; Scavo, E; Carollo, R; D'Agostino, D; Forlì, F; D'Aguanno, S; Todaro, M; Stassi, G; Di Ilio, C; De Laurenzi, V; Urbani, A

    2014-07-17

    A number of studies suggest that cancer stem cells are essential for tumour growth, and failure to target these cells can result in tumour relapse. As this population of cells has been shown to be resistant to radiation and chemotherapy, it is essential to understand their biology and identify new therapeutic approaches. Targeting cancer metabolism is a potential alternative strategy to counteract tumour growth and recurrence. Here we applied a proteomic and targeted metabolomic analysis in order to point out the main metabolic differences between breast cancer cells grown as spheres and thus enriched in cancer stem cells were compared with the same cells grown in adherent differentiating conditions. This integrated approach allowed us to identify a metabolic phenotype associated with the stem-like condition and shows that breast cancer stem cells (BCSCs) shift from mitochondrial oxidative phosphorylation towards fermentative glycolysis. Functional validation of proteomic and metabolic data provide evidences for increased activities of key enzymes of anaerobic glucose fate such as pyruvate kinase M2 isoform, lactate dehydrogenase and glucose 6-phopshate dehydrogenase in cancer stem cells as well as different redox status. Moreover, we show that treatment with 2-deoxyglucose, a well known inhibitor of glycolysis, inhibits BCSC proliferation when used alone and shows a synergic effect when used in combination with doxorubicin. In conclusion, we suggest that inhibition of glycolysis may be a potentially effective strategy to target BCSCs.

  13. miR-409-3p sensitizes colon cancer cells to oxaliplatin by inhibiting Beclin-1-mediated autophagy.

    Science.gov (United States)

    Tan, Shifan; Shi, Huijuan; Ba, Mingchen; Lin, Shengqv; Tang, Hongsheng; Zeng, Xiaoqi; Zhang, Xiangliang

    2016-04-01

    The chemoresistance of colon cancer cells limits the efficacy of chemotherapy. miR-409-3p has been shown to be downregulated in various types of cancer. In the present study, we examined the role of miR-409-3p in colon cancer as well as the effects of miR‑409-3p on the sensitivity of colon cancer cells to oxaliplatin. The expression of miR-409 was significantly downregulated in the human colon cancer cell lines compared with the normal colon epithelial cells. Importantly, the miR-409-3p expression levels were lower in human colon cancer patient samples than in normal colon tissues. Moreover, we observed a negative correlation between the miR‑409-3p levels and resistance to oxaliplatin: the oxaliplatin-resistant colon cancer cells exhibited significantly downregulated miR‑409-3p levels, but higher autophagic activity than the oxaliplatin-sensitive cells. Using bioinformatics analysis, we predicted that miR‑409-3p miRNA binds to the key autophagy gene encoding Beclin-1. Our findings indicated that the overexpression of miR‑409-3p inhibited Beclin-1 expression and autophagic activity by binding to the 3'-untranslated region of Beclin-1 mRNA. In addition, the overexpression of miR‑409-3p enhanced the chemosensitivity of the oxaliplatin-sensitive and oxaliplatin-resistant colon cancer cells. The restoration of Beclin-1 abrogated these effects of miR‑409-3p. In a xenograft model using nude mice, we examined the effects of miR‑409-3p on tumor growth during chemotherapy. miR‑409-3p overexpression sensitized the tumor to chemotherapy, while inhibiting chemotherapy-induced autophagy in a manner dependent on Beclin-1. The findings of our study suggest that miR-409-3p is capable of enhancing the chemosensitivity of colon cancer cells by inhibiting Beclin-1-mediated autophagy.

  14. NOXA-induced alterations in the Bax/Smac axis enhance sensitivity of ovarian cancer cells to cisplatin.

    Directory of Open Access Journals (Sweden)

    Chao Lin

    Full Text Available 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.

  15. NOXA-induced alterations in the Bax/Smac axis enhance sensitivity of ovarian cancer cells to cisplatin.

    Science.gov (United States)

    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.

  16. Sulforaphane Preconditioning Sensitizes Human Colon Cancer Cells towards the Bioreductive Anticancer Prodrug PR-104A.

    Directory of Open Access Journals (Sweden)

    Melanie M Erzinger

    Full Text Available The chemoprotective properties of sulforaphane (SF, derived from cruciferous vegetables, are widely acknowledged to arise from its potent induction of xenobiotic-metabolizing and antioxidant enzymes. However, much less is known about the impact of SF on the efficacy of cancer therapy through the modulation of drug-metabolizing enzymes. To identify proteins modulated by a low concentration of SF, we treated HT29 colon cancer cells with 2.5 μM SF. Protein abundance changes were detected by stable isotope labeling of amino acids in cell culture. Among 18 proteins found to be significantly up-regulated, aldo-keto reductase 1C3 (AKR1C3, bioactivating the DNA cross-linking prodrug PR-104A, was further characterized. Preconditioning HT29 cells with SF reduced the EC50 of PR-104A 3.6-fold. The increase in PR-104A cytotoxicity was linked to AKR1C3 abundance and activity, both induced by SF in a dose-dependent manner. This effect was reproducible in a second colon cancer cell line, SW620, but not in other colon cancer cell lines where AKR1C3 abundance and activity were absent or barely detectable and could not be induced by SF. Interestingly, SF had no significant influence on PR-104A cytotoxicity in non-cancerous, immortalized human colonic epithelial cell lines expressing either low or high levels of AKR1C3. In conclusion, the enhanced response of PR-104A after preconditioning with SF was apparent only in cancer cells provided that AKR1C3 is expressed, while its expression in non-cancerous cells did not elicit such a response. Therefore, a subset of cancers may be susceptible to combined food-derived component and prodrug treatments with no harm to normal tissues.

  17. Myxoma Virus Sensitizes Cancer Cells to Gemcitabine and Is an Effective Oncolytic Virotherapeutic in Models of Disseminated Pancreatic Cancer

    OpenAIRE

    Wennier, Sonia Tusell; Liu, Jia; Li, Shoudong; Rahman, Masmudur M.; Mona, Mahmoud; McFadden, Grant

    2012-01-01

    Myxoma virus (MYXV) is a novel oncolytic virus that has been shown to replicate in pancreatic cancer cells, but its efficacy in animal models of pancreatic cancer has not been determined. The efficacy of MYXV as monotherapy or in combination with gemcitabine was evaluated in intraperitoneal dissemination (IPD) models of pancreatic cancer. The effects of an intact immune system on the efficacy of MYXV therapy was tested by comparing immunodeficient versus immunocompetent murine models and comb...

  18. Mutational landscape determines sensitivity to PD-1 blockade in non–small cell lung cancer

    Science.gov (United States)

    Rizvi, Naiyer A.; Hellmann, Matthew D.; Snyder, Alexandra; Kvistborg, Pia; Makarov, Vladimir; Havel, Jonathan J.; Lee, William; Yuan, Jianda; Wong, Phillip; Ho, Teresa S.; Miller, Martin L.; Rekhtman, Natasha; Moreira, Andre L.; Ibrahim, Fawzia; Bruggeman, Cameron; Gasmi, Billel; Zappasodi, Roberta; Maeda, Yuka; Sander, Chris; Garon, Edward B.; Merghoub, Taha; Wolchok, Jedd D.; Schumacher, Ton N.; Chan, Timothy A.

    2016-01-01

    Immune checkpoint inhibitors, which unleash a patient’s own T cells to kill tumors, are revolutionizing cancer treatment. To unravel the genomic determinants of response to this therapy, we used whole-exome sequencing of non–small cell lung cancers treated with pembrolizumab, an antibody targeting programmed cell death-1 (PD-1). In two independent cohorts, higher nonsynonymous mutation burden in tumors was associated with improved objective response, durable clinical benefit, and progression-free survival. Efficacy also correlated with the molecular smoking signature, higher neoantigen burden, and DNA repair pathway mutations; each factor was also associated with mutation burden. In one responder, neoantigen-specific CD8+ T cell responses paralleled tumor regression, suggesting that anti–PD-1 therapy enhances neoantigen-specific T cell reactivity. Our results suggest that the genomic landscape of lung cancers shapes response to anti–PD-1 therapy. PMID:25765070

  19. Andrographolide sensitizes cisplatin-induced apoptosis via suppression of autophagosome-lysosome fusion in human cancer cells.

    Science.gov (United States)

    Zhou, Jing; Hu, Shuai-Er; Tan, Shi-Hao; Cao, Ruoxi; Chen, Yiyang; Xia, Dajing; Zhu, Xinqiang; Yang, Xing-Fen; Ong, Choon-Nam; Shen, Han-Ming

    2012-03-01

    Suppression of autophagy has been increasingly recognized as a novel cancer therapeutic approach. Andrographolide (Andro), a diterpenoid lactone isolated from an herbal plant Andrographis paniculata, is known to possess anti-inflammatory and anticancer activity. In this study, we sought to examine the effect of Andro on autophagy, and to evaluate whether such effect is relevant to the sensitization effect of Andro on apoptosis induced by DNA damage agents in cancer cells. First, we found that Andro is able to significantly enhance autophagic markers in various cancer cell lines, including GFP-LC3 puncta and LC3-II level. Interestingly, Andro treatment also led to marked increase of p62 protein level and addition of chloroquine (CQ) failed to further enhance either LC3-II or p62 level, indicating that Andro is likely to suppress autophagic flux at the maturation and degradation stage. Next, we provided evidence that Andro inhibits autophagosome maturation not by affecting the lysosomal function, but by impairing autophagosome-lysosome fusion. Lastly, we demonstrated that treatment with cisplatin, a DNA damage agent, induces autophagy in cancer cells. Importantly, Andro is capable of sensitizing cisplatin-induced cell killing determined with both short-term apoptosis assays and long-term clonogenic test, via suppression of autophagy, a process independent of p53. In summary, these observations collectively suggest that Andro could be a promising anti-cancer agent in combination therapy via its potent inhibitory effect on autophagy by disrupting autophagosome-lysosome fusion.

  20. The antipsychotic drug chlorpromazine enhances the cytotoxic effect of tamoxifen in tamoxifen-sensitive and tamoxifen-resistant human breast cancer cells

    DEFF Research Database (Denmark)

    Yde, Christina Westmose; Clausen, Mathias Porsmose; Bennetzen, Martin

    2009-01-01

    -glycoprotein in cancer cells. In this study, we have investigated the effect of chlorpromazine on tamoxifen response of human breast cancer cells. We found that chlorpromazine worked synergistically together with tamoxifen with respect to reduction of cell growth and metabolic activity, both in the antiestrogen......-sensitive breast cancer cell line, MCF-7, and in a tamoxifen-resistant cell line, established from the MCF-7 cells. Tamoxifen-sensitive and tamoxifen-resistant cells were killed equally well by combined treatment with chlorpromazine and tamoxifen. This synergistic effect could be prevented by addition of estrogen...

  1. Selective ALDH3A1 inhibition by benzimidazole analogues increase mafosfamide sensitivity in cancer cells.

    Science.gov (United States)

    Parajuli, Bibek; Fishel, Melissa L; Hurley, Thomas D

    2014-01-23

    Aldehyde dehydrogenase enzymes irreversibly oxidize aldehydes generated from metabolism of amino acids, fatty acids, food, smoke, additives, and xenobiotic drugs. Cyclophosphamide is one such xenobiotic used in cancer therapies. Upon activation, cyclophosphamide forms an intermediate, aldophosphamide, which can be detoxified to carboxyphosphamide by aldehyde dehydrogenases (ALDH), especially ALDH1A1 and ALDH3A1. Consequently, selective inhibition of ALDH3A1 could increase chemosensitivity toward cyclophosphamide in ALDH3A1 expressing tumors. Here, we report detailed kinetics and structural characterization of a highly selective submicromolar inhibitor of ALDH3A1, 1-[(4-fluorophenyl)sulfonyl]-2-methyl-1H-benzimidazole (CB7, IC50 of 0.2 μM). CB7 does not inhibit ALDH1A1, ALDH1A2, ALDH1A3, ALDH1B1, or ALDH2 activity. Structural, kinetics, and mutagenesis studies show that CB7 binds to the aldehyde binding pocket of ALDH3A1. ALDH3A1-expressing lung adenocarcinoma and glioblastoma cell lines are sensitized toward mafosfamide (MF) treatment in the presence analogues of CB7, whereas primary lung fibroblasts lacking ALDH3A1 expression, are not.

  2. Gambogic acid sensitizes ovarian cancer cells to doxorubicin through ROS-mediated apoptosis.

    Science.gov (United States)

    Wang, Jianxia; Yuan, Zhixiang

    2013-09-01

    Ovarian cancer is one human malignancy which has response portly to doxorubicin. The anti-cancer activity of gambogic acid has been tested in in vitro and in vivo studies. In this study, we showed that gambogic acid, a natural compound, could potentiate the anticancer activity of doxorubicin in ovarian cancer through ROS-mediated apoptosis. Platinum-resistant human ovarian cancer cell line (SKOV-3) was treated with gambogic acid, doxorubicin, or the combination of both to investigate cell proliferation and apoptosis. We found that the combination of gambogic acid and doxorubicin causes synergistic loss of cell viability in SKOV-3 cells and this synergistic effect correlated with increased cellular ROS accumulation. Moreover, in vivo results showed that gambogic acid and doxorubicin combination resulted in a synergistic suppressing effect on tumor growth in ovarian cancer mice model. Taken together, the results suggested that doxorubicin in combination with gambogic acid might provide a promising therapeutic strategy to enhance chemosensitivity of ovarian cancer to doxorubicin.

  3. Calpain activation through galectin-3 inhibition sensitizes prostate cancer cells to cisplatin treatment

    Science.gov (United States)

    Wang, Y; Nangia-Makker, P; Balan, V; Hogan, V; Raz, A

    2010-01-01

    Prostate cancer will develop chemoresistance following a period of chemotherapy. This is due, in part, to the acquisition of antiapoptotic properties by the cancer cells and, therefore, development of novel strategies for treatment is of critical need. Here, we attempt to clarify the role of the antiapoptotic molecule galectin-3 in prostate cancer cells using siRNA and antagonist approaches. The data showed that Gal-3 inhibition by siRNA or its antagonist GCS-100/modified citrus pectin (MCP) increased cisplatin-induced apoptosis of PC3 cells. Recent studies have indicated that cisplatin-induced apoptosis may be mediated by calpain, a calcium-dependent protease, as its activation leads to cleavage of androgen receptor into an androgen-independent isoform in prostate cancer cells. Thus, we examined whether calpain activation is associated with the Gal-3 function of regulating apoptosis. Here, we report that Gal-3 inhibition by siRNA or GCS-100/MCP enhances calpain activation, whereas Gal-3 overexpression inhibits it. Inhibition of calpain using its inhibitor and/or siRNA attenuated the proapoptotic effect of Gal-3 inhibition, suggesting that calpain activation may be a novel mechanism for the proapoptotic effect of Gal-3 inhibition. Thus, a paradigm shift for treating prostate cancer is suggested whereby a combination of a non-toxic anti-Gal-3 drug together with a toxic chemotherapeutic agent could serve as a novel therapeutic modality for chemoresistant prostate cancers. PMID:21368866

  4. Enhancement of Capture Sensitivity for Circulating Tumor Cells in a Breast Cancer Patient's Blood by Silicon Nanowire Platform.

    Science.gov (United States)

    Kim, Dong-Joo; Choi, Mun-Ki; Jeong, Jin-Tak; Lim, Jung-Taek; Lee, Han-Byoel; Han, Wonshik; Lee, Sang-Kwon

    2016-04-01

    The separation of circulating tumor cells (CTCs) from the blood of cancer patients with high sensitivity is an essential technique for selecting chemotherapeutic agents at a patient-by-patient level. Recently, various research groups have reported a nanostructure-based platform for rare cell capture due to its high surface area and 3D nanotopographic features. However, evaluation of capture sensitivity based on chemical modification of the nanostructure surface has not yet been performed. Here, we evaluated the capture sensitivity for CTCs from the blood of three patients diagnosed with stage IV metastatic breast cancer by using the following three platforms: streptavidin-conjugated silicon nanowire (STR-SiNW), poly-l-lysine-coated silicon nanowire (PLL-SiNW), and poly-l-lysine-coated glass (PLL-glass). The number of evaluated CTCs on STR-SiNW, PLL-SiNW, and PLL-glass were 16.2 ± 5.5 cells, 7.3 ± 2.9 cells, and 4.7 ± 1.5 cells, respectively, per 0.5 ml. Therefore, we suggest that the STR-SiNW platform is highly adaptable for the quantitative evaluation of CTCs from the blood of cancer patients in the clinical setting.

  5. Environment Dictates Dependence on Mitochondrial Complex I for NAD+ and Aspartate Production and Determines Cancer Cell Sensitivity to Metformin.

    Science.gov (United States)

    Gui, Dan Y; Sullivan, Lucas B; Luengo, Alba; Hosios, Aaron M; Bush, Lauren N; Gitego, Nadege; Davidson, Shawn M; Freinkman, Elizaveta; Thomas, Craig J; Vander Heiden, Matthew G

    2016-11-08

    Metformin use is associated with reduced cancer mortality, but how metformin impacts cancer outcomes is controversial. Although metformin can act on cells autonomously to inhibit tumor growth, the doses of metformin that inhibit proliferation in tissue culture are much higher than what has been described in vivo. Here, we show that the environment drastically alters sensitivity to metformin and other complex I inhibitors. We find that complex I supports proliferation by regenerating nicotinamide adenine dinucleotide (NAD)+, and metformin's anti-proliferative effect is due to loss of NAD+/NADH homeostasis and inhibition of aspartate biosynthesis. However, complex I is only one of many inputs that determines the cellular NAD+/NADH ratio, and dependency on complex I is dictated by the activity of other pathways that affect NAD+ regeneration and aspartate levels. This suggests that cancer drug sensitivity and resistance are not intrinsic properties of cancer cells, and demonstrates that the environment can dictate sensitivity to therapies that impact cell metabolism.

  6. Cancer immunology. Mutational landscape determines sensitivity to PD-1 blockade in non-small cell lung cancer.

    Science.gov (United States)

    Rizvi, Naiyer A; Hellmann, Matthew D; Snyder, Alexandra; Kvistborg, Pia; Makarov, Vladimir; Havel, Jonathan J; Lee, William; Yuan, Jianda; Wong, Phillip; Ho, Teresa S; Miller, Martin L; Rekhtman, Natasha; Moreira, Andre L; Ibrahim, Fawzia; Bruggeman, Cameron; Gasmi, Billel; Zappasodi, Roberta; Maeda, Yuka; Sander, Chris; Garon, Edward B; Merghoub, Taha; Wolchok, Jedd D; Schumacher, Ton N; Chan, Timothy A

    2015-04-03

    Immune checkpoint inhibitors, which unleash a patient's own T cells to kill tumors, are revolutionizing cancer treatment. To unravel the genomic determinants of response to this therapy, we used whole-exome sequencing of non-small cell lung cancers treated with pembrolizumab, an antibody targeting programmed cell death-1 (PD-1). In two independent cohorts, higher nonsynonymous mutation burden in tumors was associated with improved objective response, durable clinical benefit, and progression-free survival. Efficacy also correlated with the molecular smoking signature, higher neoantigen burden, and DNA repair pathway mutations; each factor was also associated with mutation burden. In one responder, neoantigen-specific CD8+ T cell responses paralleled tumor regression, suggesting that anti-PD-1 therapy enhances neoantigen-specific T cell reactivity. Our results suggest that the genomic landscape of lung cancers shapes response to anti-PD-1 therapy.

  7. Inhibition of glucose turnover by 3-bromopyruvate counteracts pancreatic cancer stem cell features and sensitizes cells to gemcitabine

    OpenAIRE

    Isayev, Orkhan; Rausch, Vanessa; Bauer, Nathalie; Liu, Li; Fan, Pei; Zhang, Yiyao; Gladkich, Jury; Nwaeburu, Clifford C.; Mattern, Jürgen; Mollenhauer, Martin; Rückert, Felix; Zach, Sebastian; Haberkorn, Uwe; Gross, Wolfgang; Schönsiegel, Frank

    2014-01-01

    According to the cancer stem cell (CSC) hypothesis, the aggressive growth and early metastasis of pancreatic ductal adenocarcinoma (PDA) is due to the activity of CSCs, which are not targeted by current therapies. Otto Warburg suggested that the growth of cancer cells is driven by a high glucose metabolism. Here, we investigated whether glycolysis inhibition targets CSCs and thus may enhance therapeutic efficacy. Four established and 3 primary PDA cell lines, non-malignant cells, and 3 patien...

  8. A cell-permeable dominant-negative survivin protein induces apoptosis and sensitizes prostate cancer cells to TNF-α therapy

    Directory of Open Access Journals (Sweden)

    Kanwar Jagat R

    2010-10-01

    Full Text Available Abstract Background Survivin is a member of the inhibitor-of-apoptosis (IAP family which is widely expressed by many different cancers. Overexpression of survivin is associated with drug resistance in cancer cells, and reduced patient survival after chemotherapy and radiotherapy. Agents that antagonize the function of survivin hold promise for treating many forms of cancer. The purpose of this study was to investigate whether a cell-permeable dominant-negative survivin protein would demonstrate bioactivity against prostate and cervical cancer cells grown in three dimensional culture. Results A dominant-negative survivin (C84A protein fused to the cell penetrating peptide poly-arginine (R9 was expressed in E. coli and purified by affinity chromatography. Western blot analysis revealed that dNSurR9-C84A penetrated into 3D-cultured HeLa and DU145 cancer cells, and a cell viability assay revealed it induced cancer cell death. It increased the activities of caspase-9 and caspase-3, and rendered DU145 cells sensitive to TNF-α via by a mechanism involving activation of caspase-8. Conclusions The results demonstrate that antagonism of survivin function triggers the apoptosis of prostate and cervical cancer cells grown in 3D culture. It renders cancer cells sensitive to the proapoptotic affects of TNF-α, suggesting that survivin blocks the extrinsic pathway of apoptosis. Combination of the biologically active dNSurR9-C84A protein or other survivin antagonists with TNF-α therapy warrants consideration as an approach to cancer therapy.

  9. Reduced PAK1 activity sensitizes FA/BRCA-proficient breast cancer cells to PARP inhibition.

    Science.gov (United States)

    Villamar Cruz, Olga; Prudnikova, Tatiana Y; Araiza-Olivera, Daniela; Perez-Plasencia, Carlos; Johnson, Neil; Bernhardy, Andrea J; Slifker, Michael; Renner, Catherine; Chernoff, Jonathan; Arias-Romero, Luis E

    2016-11-22

    Cells that are deficient in homologous recombination, such as those that have mutations in any of the Fanconi Anemia (FA)/BRCA genes, are hypersensitive to inhibition of poly(ADP-ribose) polymerase (PARP). However, FA/BRCA-deficient tumors represent a small fraction of breast cancers, which might restrict the therapeutic utility of PARP inhibitor monotherapy. The gene encoding the serine-threonine protein kinase p21-activated kinase 1 (PAK1) is amplified and/or overexpressed in several human cancer types including 25-30% of breast tumors. This enzyme controls many cellular processes by phosphorylating both cytoplasmic and nuclear substrates. Here, we show that depletion or pharmacological inhibition of PAK1 down-regulated the expression of genes involved in the FA/BRCA pathway and compromised the ability of cells to repair DNA by Homologous Recombination (HR), promoting apoptosis and reducing colony formation. Combined inhibition of PAK1 and PARP in PAK1 overexpressing breast cancer cells had a synergistic effect, enhancing apoptosis, suppressing colony formation, and delaying tumor growth in a xenograft setting. Because reduced PAK1 activity impaired FA/BRCA function, inhibition of this kinase in PAK1 amplified and/or overexpressing breast cancer cells represents a plausible strategy for expanding the utility of PARP inhibitors to FA/BRCA-proficient cancers.

  10. Genipin-induced inhibition of uncoupling protein-2 sensitizes drug-resistant cancer cells to cytotoxic agents.

    Directory of Open Access Journals (Sweden)

    Ryan J Mailloux

    Full Text Available Uncoupling protein-2 (UCP2 is known to suppress mitochondrial reactive oxygen species (ROS production and is employed by drug-resistant cancer cells to mitigate oxidative stress. Using the drug-sensitive HL-60 cells and the drug-resistant MX2 subline as model systems, we show that genipin, a UCP2 inhibitor, sensitizes drug-resistant cells to cytotoxic agents. Increased MX2 cell death was observed upon co-treatment with genipin and different doses of menadione, doxorubicin, and epirubicin. DCFH-DA fluorimetry revealed that the increase in MX2 cell death was accompanied by enhanced cellular ROS levels. The drug-induced increase in ROS was linked to genipin-mediated inhibition of mitochondrial proton leak. State 4 and resting cellular respiratory rates were higher in the MX2 cells in comparison to the HL-60 cells, and the increased respiration was readily suppressed by genipin in the MX2 cells. UCP2 accounted for a remarkable 37% of the resting cellular oxygen consumption indicating that the MX2 cells are functionally reliant on this protein. Higher amounts of UCP2 protein were detected in the MX2 versus the HL-60 mitochondria. The observed effects of genipin were absent in the HL-60 cells pointing to the selectivity of this natural product for drug-resistant cells. The specificity of genipin for UCP2 was confirmed using CHO cells stably expressing UCP2 in which genipin induced an ∼22% decrease in state 4 respiration. These effects were absent in empty vector CHO cells expressing no UCP2. Thus, the chemical inhibition of UCP2 with genipin sensitizes multidrug-resistant cancer cells to cytotoxic agents.

  11. Effects of a novel porphyrin-based photosensitizer on sensitive and multidrug-resistant human gastric cancer cell lines.

    Science.gov (United States)

    Chen, Jingjing; Mao, Lina; Liu, Shuping; Liang, Yanling; Wang, Sicheng; Wang, Yeyu; Zhao, Qiang; Zhang, Xiaojing; Che, Yanjun; Gao, Lijing; Liu, Tianjun

    2015-10-01

    Photodynamic therapy (PDT) has been considered to be a possible candidate approach in combating multidrug resistance (MDR) phenomenon during the treatment of cancer. To investigate the photocytotoxicity of a novel porphyrin-based photosensitizer, meso-5-[ρ-DTPA-aminophenyl]-10, 15, 20-triphenyl-porhyrin (DTP) (Fig. 1A), on MDR cells, the intracellular DTP uptake, phototoxicity and subcellular DTP localization were studied by using a human gastric cancer MGC803 cell line and its paclitaxel selected subline MGC803/PA expressing MDR phenotype. No significant difference was observed in intracellular DTP accumulation between sensitive and resistant cell lines after exposure to 1.56 μM concentration for 6h. DTP-PDT induced significant photocytotoxicity on both MGC803 and MGC803/PA cell lines and the photokilling was greater in MGC803 cell line in comparison to MGC803/PA. The fluence that caused 50% cell death was 4.42 and 6.29 J/cm(2) in MGC803 and MGC803/PA cell lines, respectively. The presence of Pgp inhibitors verapamil and cyclosporin A could not modify the intracellular DTP level in MGC803/PA cell line and the phototoxic effects. DTP was localized at lysosomes of MGC803 cell line but at lysosomes and mitochondria of MGC803/PA. Our results indicated that DTP-mediated PDT could eradicate gastric cancer cells whether or not they express MDR although the efficacy is slightly reduced in the MDR cells. The photokilling in MDR cells could not be altered by MDR inhibitor verapamil. The slightly different photocytotoxicity between sensitive and resistant cell lines could not explained by classical Pgp MDR and might be attributed to the differential intracellular DTP localization sites.

  12. A sensitive test for the detection of specific DSB repair defects in primary cells from breast cancer specimens.

    Science.gov (United States)

    Keimling, Marlen; Kaur, Jatinder; Bagadi, Sarangadhara Appala Raju; Kreienberg, Rolf; Wiesmüller, Lisa; Ralhan, Ranju

    2008-08-01

    Increasing evidence indicates that breast cancer pathogenesis is linked with DNA double-strand break (DSB) repair dysfunction. This conclusion is based on advances in the study of functions of breast cancer susceptibility genes such as BRCA1 and BRCA2, on the identification of breast cancer-associated changes regarding the genetics, expression, and localization of multiple DSB repair factors, and on observations indicating enhanced radiation-induced chromosomal damage in cells from predisposed individuals and sporadic breast cancer patients. In this pilot study, we describe a sensitive method for the analysis of DSB repair functions in mammary carcinomas. Using this method we firstly document alterations in pathway-specific DSB repair activities in primary cells originating from familial as well as sporadic breast cancer. In particular, we identified increases in the mutagenic nonhomologous end joining and single-strand annealing mechanisms in sporadic breast cancers with wild-type BRCA1 and BRCA2, and, thus, similar phenotypes to tumors with mutant alleles of BRCA1 and BRCA2. This suggests that detection of error-prone DSB repair activities may be useful to extend the limits of genotypic characterization of high-risk susceptibility genes. This method may, therefore, serve as a marker for breast cancer risk assessment and, even more importantly, for the prediction of responsiveness to targeted therapies such as to inhibitors of poly(ADP-ribose)polymerase (PARP1).

  13. Targeting miR-21 enhances the sensitivity of human colon cancer HT-29 cells to chemoradiotherapy in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Deng, Jun; Lei, Wan; Fu, Jian-Chun; Zhang, Ling; Li, Jun-He; Xiong, Jian-Ping, E-mail: jpxiong@medmail.com.cn

    2014-01-17

    Highlight: •MiR-21 plays a significant role in 5-FU resistance. •This role might be attributed to targeting of hMSH2 as well as TP and DPD via miR-21 targeted hMSH2. •Indirectly targeted TP and DPD to influence 5-FU chemotherapy sensitivity. -- Abstract: 5-Fluorouracil (5-FU) is a classic chemotherapeutic drug that has been widely used for colorectal cancer treatment, but colorectal cancer cells are often resistant to primary or acquired 5-FU therapy. Several studies have shown that miR-21 is significantly elevated in colorectal cancer. This suggests that this miRNA might play a role in this resistance. In this study, we investigated this possibility and the possible mechanism underlying this role. We showed that forced expression of miR-21 significantly inhibited apoptosis, enhanced cell proliferation, invasion, and colony formation ability, promoted G1/S cell cycle transition and increased the resistance of tumor cells to 5-FU and X radiation in HT-29 colon cancer cells. Furthermore, knockdown of miR-21 reversed these effects on HT-29 cells and increased the sensitivity of HT-29/5-FU to 5-FU chemotherapy. Finally, we showed that miR-21 targeted the human mutS homolog2 (hMSH2), and indirectly regulated the expression of thymidine phosphorylase (TP) and dihydropyrimidine dehydrogenase (DPD). These results demonstrate that miR-21 may play an important role in the 5-FU resistance of colon cancer cells.

  14. Discrimination of bladder cancer cells from normal urothelial cells with high specificity and sensitivity: combined application of atomic force microscopy and modulated Raman spectroscopy.

    Science.gov (United States)

    Canetta, Elisabetta; Riches, Andrew; Borger, Eva; Herrington, Simon; Dholakia, Kishan; Adya, Ashok K

    2014-05-01

    Atomic force microscopy (AFM) and modulated Raman spectroscopy (MRS) were used to discriminate between living normal human urothelial cells (SV-HUC-1) and bladder tumour cells (MGH-U1) with high specificity and sensitivity. MGH-U1 cells were 1.5-fold smaller, 1.7-fold thicker and 1.4-fold rougher than normal SV-HUC-1 cells. The adhesion energy was 2.6-fold higher in the MGH-U1 cells compared to normal SV-HUC-1 cells, which possibly indicates that bladder tumour cells are more deformable than normal cells. The elastic modulus of MGH-U1 cells was 12-fold lower than SV-HUC-1 cells, suggesting a higher elasticity of the bladder cancer cell membranes. The biochemical fingerprints of cancer cells displayed a higher DNA and lipid content, probably due to an increase in the nuclear to cytoplasm ratio. Normal cells were characterized by higher protein contents. AFM studies revealed a decrease in the lateral dimensions and an increase in thickness of cancer cells compared to normal cells; these studies authenticate the observations from MRS. Nanostructural, nanomechanical and biochemical profiles of bladder cells provide qualitative and quantitative markers to differentiate between normal and cancerous cells at the single cellular level. AFM and MRS allow discrimination between adhesion energy, elasticity and Raman spectra of SV-HUC-1 and MGH-U1 cells with high specificity (83, 98 and 95%) and sensitivity (97, 93 and 98%). Such single-cell-level studies could have a pivotal impact on the development of AFM-Raman combined methodologies for cancer profiling and screening with translational significance.

  15. Inhibitor-sensitive FGFR1 amplification in human non-small cell lung cancer.

    Directory of Open Access Journals (Sweden)

    Amit Dutt

    Full Text Available BACKGROUND: Squamous cell lung carcinomas account for approximately 25% of new lung carcinoma cases and 40,000 deaths per year in the United States. Although there are multiple genomically targeted therapies for lung adenocarcinoma, none has yet been reported in squamous cell lung carcinoma. METHODOLOGY/PRINCIPAL FINDINGS: Using SNP array analysis, we found that a region of chromosome segment 8p11-12 containing three genes-WHSC1L1, LETM2, and FGFR1-is amplified in 3% of lung adenocarcinomas and 21% of squamous cell lung carcinomas. Furthermore, we demonstrated that a non-small cell lung carcinoma cell line harboring focal amplification of FGFR1 is dependent on FGFR1 activity for cell growth, as treatment of this cell line either with FGFR1-specific shRNAs or with FGFR small molecule enzymatic inhibitors leads to cell growth inhibition. CONCLUSIONS/SIGNIFICANCE: These studies show that FGFR1 amplification is common in squamous cell lung cancer, and that FGFR1 may represent a promising therapeutic target in non-small cell lung cancer.

  16. Genetic disruption of oncogenic Kras sensitizes lung cancer cells to Fas receptor-mediated apoptosis.

    Science.gov (United States)

    Mou, Haiwei; Moore, Jill; Malonia, Sunil K; Li, Yingxiang; Ozata, Deniz M; Hough, Soren; Song, Chun-Qing; Smith, Jordan L; Fischer, Andrew; Weng, Zhiping; Green, Michael R; Xue, Wen

    2017-04-04

    Genetic lesions that activate KRAS account for ∼30% of the 1.6 million annual cases of lung cancer. Despite clinical need, KRAS is still undruggable using traditional small-molecule drugs/inhibitors. When oncogenic Kras is suppressed by RNA interference, tumors initially regress but eventually recur and proliferate despite suppression of Kras Here, we show that tumor cells can survive knockout of oncogenic Kras, indicating the existence of Kras-independent survival pathways. Thus, even if clinical KRAS inhibitors were available, resistance would remain an obstacle to treatment. Kras-independent cancer cells exhibit decreased colony formation in vitro but retain the ability to form tumors in mice. Comparing the transcriptomes of oncogenic Kras cells and Kras knockout cells, we identified 603 genes that were specifically up-regulated in Kras knockout cells, including the Fas gene, which encodes a cell surface death receptor involved in physiological regulation of apoptosis. Antibodies recognizing Fas receptor efficiently induced apoptosis of Kras knockout cells but not oncogenic Kras-expressing cells. Increased Fas expression in Kras knockout cells was attributed to decreased association of repressive epigenetic marks at the Fas promoter. Concordant with this observation, treating oncogenic Kras cells with histone deacetylase inhibitor and Fas-activating antibody efficiently induced apoptosis, thus bypassing the need to inhibit Kras. Our results suggest that activation of Fas could be exploited as an Achilles' heel in tumors initiated by oncogenic Kras.

  17. Cell Line Derived 5-FU and Irinotecan Drug-Sensitivity Profiles Evaluated in Adjuvant Colon Cancer Trial Data

    DEFF Research Database (Denmark)

    Buhl, Ida Kappel; Gerster, Sarah; Delorenzi, Mauro

    2016-01-01

    PURPOSE: This study evaluates whether gene signatures for chemosensitivity for irinotecan and 5-fluorouracil (5-FU) derived from in vitro grown cancer cell lines can predict clinical sensitivity to these drugs. METHODS: To test if an irinotecan signature and a SN-38 signature could identify...... patients who benefitted from the addition of irinotecan to 5-FU, we used gene expression profiles based on cell lines and clinical tumor material. These profiles were applied to expression data obtained from pretreatment formalin fixed paraffin embedded (FFPE) tumor tissue from 636 stage III colon cancer...... patients enrolled in the PETACC-3 prospective randomized clinical trial. A 5-FU profile developed similarly was assessed by comparing the PETACC-3 cohort with a cohort of 359 stage II colon cancer patients who underwent surgery but received no adjuvant therapy. RESULTS: There was no statistically...

  18. Novel psammaplin A derivatives sensitize human cancer cells to x-ray irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jin Ho; Kim, Hak Jae; Wee, Chan Woo; Suh, Soo Youn; Kim, Il Han [Seoul National University College of Medicine, Seoul (Korea, Republic of); Ma, Eun Sook; Shin, Beom Soo [College of Pharmacy, Catholic University of Daegu. Daegu (Korea, Republic of)

    2015-04-15

    Since therapeutics such as temozolomide (TMZ) showed survival benefit in a particular subgroup of patients whose cancer cells carried methylated O6-methylguanin-DNA methyltransferase genes, the field of developing novel epigenic anticancer agents seems promising. DNA methylation and histone modifications are the two principal factors in epigenetic phenomena. These two mechanisms perform a crucial function in carcinogenesis and tumor progression. DNA methylation is controlled by DNA methyltransferase (DNMT), which have been detected to be over expressed in a variety of malignancies. As a nucleoside or a non-nucleoside, DNMT inhibitors demonstrate anticancer effects by directly trapping DNMTs or by blocking DNMTs at a proper site, respectively. Psammaplin A (PsA) is an inhibitor of both DNA methyltransferase (DNMT) and histone deacetylase inhibitor, and as previously reported from our institution, enhances radiation cell killing by increasing the sub-G1 fraction of cancer cells compared to cells exposed to radiation alone.

  19. Evaluation of candidate biomarkers to predict cancer cell sensitivity or resistance to PARP-1 inhibitor treatment

    DEFF Research Database (Denmark)

    Oplustilova, L.; Wolanin, K.; Bartkova, J.

    2012-01-01

    resistance efux transporters and its reversibility. More importantly, we demonstrated that shRNA lentivirus-mediated depletion of 53Bp1 in human BRCA1-mutant breast cancer cells increased their resistance to PARP-1i. Given the preferential loss of 53Bp1 in BRCA-defective and triple-negative breast carcinomas...

  20. Myxoma virus sensitizes cancer cells to gemcitabine and is an effective oncolytic virotherapeutic in models of disseminated pancreatic cancer.

    Science.gov (United States)

    Wennier, Sonia Tusell; Liu, Jia; Li, Shoudong; Rahman, Masmudur M; Mona, Mahmoud; McFadden, Grant

    2012-04-01

    Myxoma virus (MYXV) is a novel oncolytic virus that has been shown to replicate in pancreatic cancer cells, but its efficacy in animal models of pancreatic cancer has not been determined. The efficacy of MYXV as monotherapy or in combination with gemcitabine was evaluated in intraperitoneal dissemination (IPD) models of pancreatic cancer. The effects of an intact immune system on the efficacy of MYXV therapy was tested by comparing immunodeficient versus immunocompetent murine models and combination therapy with gemcitabine was also evaluated. In cell culture, MYXV replication was robust in a broad range of pancreatic cancer cells and also showed increased oncolysis in combination with gemcitabine. In animal models, MYXV treatment conferred survival benefits over control or gemcitabine-treated cohorts regardless of the cell line or animal model used. MYXV monotherapy was most effective in an immunocompetent IPD model, and resulted in 60% long-term survivors. In Pan02 engrafted immunocompetent IPD models, sequential treatment in which MYXV was administered first, followed by gemcitabine, was the most effective and resulted in 100% long-term survivors. MYXV is an effective oncolytic virus for pancreatic cancer and can be combined with gemcitabine to enhance survival, particularly in the presence of an intact host immune system.

  1. Effects of Smac gene over-expression on the radiotherapeutic sensitivities of cervical cancer cell line HeLa

    Institute of Scientific and Technical Information of China (English)

    ZHENG Li-duan; XIONG Zhou-fang; ZHU Jian-wen; WANG Ze-hua

    2005-01-01

    Background The second mitochondria-derived activator of caspases (Smac) is a novel proapoptotic gene, which plays an important role in the apoptosis-inducing effects of irradiation on tumor cells. The purpose of this study was to investigate the effects of extrinsic Smac gene transfer and its over-expression in radiotherapeutic sensitivities of cervical cancer cells. Methods After the Smac gene was transferred into the cervical cancer cell line HeLa, subcloned cells were obtained by persistent G418 selection. Cellular Smac gene expression was detected by RT-PCR and Western blot, while in vitro cell viabilities were detected by trypan blue staining assay. After treatment with X-ray irradiation, cellular radiotherapeutic sensitivities were investigated by tetrazolium bromide colorimetry. Cellular apoptosis and its rate were determined by electronic microscopy, annexin V-FITC and propidium iodide staining flow cytometry. The expression and activities of cellular caspase-3 were assayed by Western blot and colorimetry. Results Smac mRNA and protein levels in HeLa/Smac cells and the selected subclone cell line of cervical cancer were significantly higher than those of HeLa (P0.05). However, after irradiation with 8 Gy X-ray, growth activities of HeLa/Smac were reduced by 22.42% (P<0.01). When compared with those of HeLa, partial HeLa/Smac cells presented characteristic morphological changes of apoptosis under electronic microscope, with higher apoptosis rates (16.4% vs. 6.2%, P<0.01); the caspase-3 expression levels in HeLa/Smac cells were improved significantly (P<0.01), while its activities were increased by 3.42 times (P<0.01).Conclusions Stable transfer of the extrinsic Smac gene and its over-expression in cervical cancer cell line could significantly enhance the expression and activities of cellular caspase-3 and ameliorate apoptosis-inducing effects of irradiation on cancer cells, which was a novel strategy to improve radiotherapeutic effects on cervical cancer.

  2. Label-free electrochemical aptasensor constructed by layer-by-layer technology for sensitive and selective detection of cancer cells.

    Science.gov (United States)

    Wang, Tianshu; Liu, Jiyang; Gu, Xiaoxiao; Li, Dan; Wang, Jin; Wang, Erkang

    2015-07-02

    Here, a cytosensor was constructed with ferrocene-appended poly(allylamine hydrochloride) (Fc-PAH) functionalized graphene (Fc-PAH-G), poly(sodium-p-styrenesulfonate) (PSS) and aptamer (AS1411) by layer-by-layer assembly technology. The hybrid nanocomposite Fc-PAH-G not only brings probes on the electrode and also promotes electron transfer between the probes and the substrate electrode. Meanwhile, LBL technology provides more effective probes to enhance amplified signal for improving the sensitivity of the detection. While AS1411 forming G-quardruplex structure and binding cancer cells, the current response of the sensing electrode decreased due to the insulating properties of cellular membrane. Differential pulse voltammetry (DPV) was performed to investigate the electrochemical detection of HeLa cells attributing to its sensitivity of the current signal change. The as-prepared aptasensor showed a high sensitivity and good stability, a widely detection range from 10 to 10(6) cells/mL with a detection limit as low as 10 cells/mL for the detection of cancer cells.

  3. The resistance of breast cancer stem cells to conventional hyperthermia and their sensitivity to nanoparticle-mediated photothermal therapy.

    Science.gov (United States)

    Burke, Andrew R; Singh, Ravi N; Carroll, David L; Wood, James C S; D'Agostino, Ralph B; Ajayan, Pulickel M; Torti, Frank M; Torti, Suzy V

    2012-04-01

    Breast tumors contain a small population of tumor initiating stem-like cells, termed breast cancer stem cells (BCSCs). These cells, which are refractory to chemotherapy and radiotherapy, are thought to persist following treatment and drive tumor recurrence. We examined whether BCSCs are similarly resistant to hyperthermic therapy, and whether nanoparticles could be used to overcome this resistance. Using a model of triple-negative breast cancer stem cells, we show that BCSCs are markedly resistant to traditional hyperthermia and become enriched in the surviving cell population following treatment. In contrast, BCSCs are sensitive to nanotube-mediated thermal treatment and lose their long-term proliferative capacity after nanotube-mediated thermal therapy. Moreover, use of this therapy in vivo promotes complete tumor regression and long-term survival of mice bearing cancer stem cell-driven breast tumors. Mechanistically, nanotube thermal therapy promotes rapid membrane permeabilization and necrosis of BCSCs. These data suggest that nanotube-mediated thermal treatment can simultaneously eliminate both the differentiated cells that constitute the bulk of a tumor and the BCSCs that drive tumor growth and recurrence.

  4. Radio-sensitization of Prostate Cancer Cells by Monensin Treatment and its associated Gene Expression Profiling Changes

    Science.gov (United States)

    Zhang Ye; Rohde, Larry H.; Wu, Honglu

    2008-01-01

    Radio-resistant or recurrent prostate cancer represents a serious health risk for approximately 20%-30% of patients treated with primary radiation therapy for clinically localized prostate cancer. Here, we investigated the effect of monensin on sensitizing radiation mediated cell killing of two radio-resistant prostate cell lines Lncap (P53+ and AR+) and PC3 (P53- and AR-). Treatment with monensin alone (5 micromoles-20 micromoles) showed a significant direct cell killing of Lncap (10-30%), but not PC3 cells. Monensin was also shown to successfully sensitize Lncap cells to X-ray radiation (2Gy-10Gy) mediated cell death, up to 50% of killing with the combined treatment. To better understand the mechanisms of radio-resistance of these two cell lines and their different response to monensin, the apoptosis related gene expression profiles in both cell lines were analyzed using cDNA PCR array. Without any treatment, PC3 showed a much higher expression level of antiapoptosis genes than Lncap in the BCL2 family, the caspase/card family and the TNF ligand/receptor family. At 2 hr after 20 micormolar monensin treatment alone, only the TRAF and CIDE family showed a greater induction in Lncap cells than in PC3. Exposures to 10 Gy X-rays alone of Lncap cells significantly induced gene expression levels in the death and death receptor domain family, the TNF ligand and receptor family, and apoptotic group of BCL2 family; whereas exposures of PC3 induced only the expression of genes in the anti-apoptosis group of CASP and CARD family. Furthermore, we selectively suppressed the expression of several anti-apoptosis genes (BCL-xl, Bcl2A1, BIRC2, BIRC3 and CASP2) in PC3 cells by using the siRNA treatment. Exposure to 10Gy X-rays alone showed an enhanced cell killing (about 15%) in BCL-x1 silenced cells, but not in cells with siRNA treatment targeting other anti-apoptosis genes. We also exposed PC3 cells to protons in the Bragg peak region to compare the effectiveness of cell killing

  5. Phellinus linteus extract sensitizes advanced prostate cancer cells to apoptosis in athymic nude mice.

    Science.gov (United States)

    Tsuji, Takanori; Du, Wei; Nishioka, Takashi; Chen, Lihua; Yamamoto, Daisuke; Chen, Chang Yan

    2010-03-31

    Phellinus linteus (PL) mushroom possesses anti-tumor property. We previously reported that the treatment with PL caused cultured human prostate cancer cells to undergo apoptosis. To further studying the mechanisms of PL-mediated apoptosis, we performed xenograft assay, together with in vitro assays, to evaluate the effect of PL on the genesis and progression of the tumors formed from the inoculation of prostate cancer PC3 or DU145 cells. After the inoculation, nude mice were injected with PL every two days for 12 days. Although PL treatment did not prevent the formation of the inoculated tumors, the growth rate of the tumors after PL treatment was dramatically attenuated. We then tested the effect of PL on the tumors 12 days after the inoculation. After inoculated tumors reached a certain size, PL was administrated to the mice by subcutaneous injection. The histochemistry or immunochemistry analysis showed that apoptosis occurred with the activation of caspase 3 in the tumors formed by inoculating prostate cancer DU145 or PC3 cells. The data was in a good agreement with that from cultured cells. Thus, our in vivo study suggests that PL not only is able to attenuate tumor growth, but also to cause tumor regression by inducing apoptosis.

  6. Phellinus linteus extract sensitizes advanced prostate cancer cells to apoptosis in athymic nude mice.

    Directory of Open Access Journals (Sweden)

    Takanori Tsuji

    Full Text Available Phellinus linteus (PL mushroom possesses anti-tumor property. We previously reported that the treatment with PL caused cultured human prostate cancer cells to undergo apoptosis. To further studying the mechanisms of PL-mediated apoptosis, we performed xenograft assay, together with in vitro assays, to evaluate the effect of PL on the genesis and progression of the tumors formed from the inoculation of prostate cancer PC3 or DU145 cells. After the inoculation, nude mice were injected with PL every two days for 12 days. Although PL treatment did not prevent the formation of the inoculated tumors, the growth rate of the tumors after PL treatment was dramatically attenuated. We then tested the effect of PL on the tumors 12 days after the inoculation. After inoculated tumors reached a certain size, PL was administrated to the mice by subcutaneous injection. The histochemistry or immunochemistry analysis showed that apoptosis occurred with the activation of caspase 3 in the tumors formed by inoculating prostate cancer DU145 or PC3 cells. The data was in a good agreement with that from cultured cells. Thus, our in vivo study suggests that PL not only is able to attenuate tumor growth, but also to cause tumor regression by inducing apoptosis.

  7. Cucurbitacin B Causes Increased Radiation Sensitivity of Human Breast Cancer Cells via G2/M Cell Cycle Arrest

    Directory of Open Access Journals (Sweden)

    Suwit Duangmano

    2012-01-01

    Full Text Available Purpose. To explore the effects of cucurbitacin B on the radiation survival of human breast cancer cells and to elucidate the cellular mechanism of radiosensitization if any. Materials and Methods. Human breast carcinoma cell lines were treated with cucurbitacin B before irradiation with 0–10 Gy of C137s gamma rays. The effect of cucurbitacin B on cell-survival following irradiation was evaluated by colony-forming assay. Cell cycle distributions were investigated using flow cytometry. Real-time PCR and western blots were performed to investigate the expression of cell cycle checkpoints. Results. Cucurbitacin B inhibited breast cancer cell proliferation in a dose-dependent manner. Only MDA-MB-231 and MCF7:5C cells but not SKBR-3 cells were radiosensitized by cucurbitacin B. Flow cytometric analysis for DNA content indicated that cucurbitacin B resulted in G2/M arrest in MDA-MB-231 and MCF7:5C but not SKBR-3 cells. Moreover, Real-time PCR and western blot analysis demonstrated upregulated p21 expression before irradiation, a likely cause of the cell cycle arrest. Conclusion. Taken together, these findings suggest that cucurbitacin B causes radiosensitization of some breast cancer cells, and that cucurbitacin B induced G2/M arrest is an important mechanism. Therefore, combinations of cucurbitacin B with radiotherapy may be appropriate for experimental breast cancer treatment.

  8. Chromatin status of apoptosis genes correlates with sensitivity to chemo-, immune- and radiation therapy in colorectal cancer cell lines.

    Science.gov (United States)

    Benard, Anne; Janssen, Connie M; van den Elsen, Peter J; van Eggermond, Marja C J A; Hoon, Dave S B; van de Velde, Cornelis J H; Kuppen, Peter J K

    2014-12-01

    The apoptosis pathway of programmed cell death is frequently deregulated in cancer. An intact apoptosis pathway is required for proper response to anti-cancer treatment. We investigated the chromatin status of key apoptosis genes in the apoptosis pathway in colorectal cancer cell lines in relation to apoptosis induced by chemo-, immune- or radiation therapy. Using chromatin immunoprecipitation (ChIP), we measured the presence of transcription-activating histone modifications H3Ac and H3K4me3 and silencing modifications H3K9me3 and H3K27me3 at the gene promoter regions of key apoptosis genes Bax, Bcl2, Caspase-9, Fas (CD95) and p53. Cell lines DLD1, SW620, Colo320, Caco2, Lovo and HT29 were treated with cisplatin, anti-Fas or radiation. The apoptotic response was measured by flow cytometry using propidium iodide and annexin V-FITC. The chromatin status of the apoptosis genes reflected the activation status of the intrinsic (Bax, Bcl2, Caspase-9 and p53) and extrinsic (Fas) pathways. An active intrinsic apoptotic pathway corresponded to sensitivity to cisplatin and radiation treatment of cell lines DLD1, SW620 and Colo320. An active Fas promoter corresponded to an active extrinsic apoptotic pathway in cell line DLD1. mRNA expression data correlated with the chromatin status of the apoptosis genes as measured by ChIP. In conclusion, the results presented in this study indicate that the balance between activating and silencing histone modifications, reflecting the chromatin status of apoptosis genes, can be used to predict the response of tumor cells to different anti-cancer therapies and could provide a novel target to sensitize tumors to obtain adequate treatment responses.

  9. Sensitive and Specific Biomimetic Lipid Coated Microfluidics to Isolate Viable Circulating Tumor Cells and Microemboli for Cancer Detection.

    Directory of Open Access Journals (Sweden)

    Jia-Yang Chen

    Full Text Available Here we presented a simple and effective membrane mimetic microfluidic device with antibody conjugated supported lipid bilayer (SLB "smart coating" to capture viable circulating tumor cells (CTCs and circulating tumor microemboli (CTM directly from whole blood of all stage clinical cancer patients. The non-covalently bound SLB was able to promote dynamic clustering of lipid-tethered antibodies to CTC antigens and minimized non-specific blood cells retention through its non-fouling nature. A gentle flow further flushed away loosely-bound blood cells to achieve high purity of CTCs, and a stream of air foam injected disintegrate the SLB assemblies to release intact and viable CTCs from the chip. Human blood spiked cancer cell line test showed the ~95% overall efficiency to recover both CTCs and CTMs. Live/dead assay showed that at least 86% of recovered cells maintain viability. By using 2 mL of peripheral blood, the CTCs and CTMs counts of 63 healthy and colorectal cancer donors were positively correlated with the cancer progression. In summary, a simple and effective strategy utilizing biomimetic principle was developed to retrieve viable CTCs for enumeration, molecular analysis, as well as ex vivo culture over weeks. Due to the high sensitivity and specificity, it is the first time to show the high detection rates and quantity of CTCs in non-metastatic cancer patients. This work offers the values in both early cancer detection and prognosis of CTC and provides an accurate non-invasive strategy for routine clinical investigation on CTCs.

  10. Knockdown of NAPA using short-hairpin RNA sensitizes cancer cells to cisplatin: implications to overcome chemoresistance.

    Science.gov (United States)

    Wu, Zchong-Zcho; Chao, Chuck C-K

    2010-09-15

    Cisplatin is a widely used anti-cancer drug which targets DNA in replicating cells. In the present study, we found that NAPA--a protein found in the endoplasmic reticulum (ER) and implicated in protein trafficking--protects cells against cisplatin. Accordingly, knockdown of NAPA using lentivirus-encoded shRNA (shNAPA) induced ER stress similar to cisplatin treatment in HEK293 cells. A low dose of cisplatin also elicited a mild ER stress response associated with the accumulation of the protective proteins BiP and NAPA. Remarkably, knockdown of NAPA induced apoptosis and enhanced cisplatin-induced cytotoxicity/apoptosis, thereby sensitizing cancer cells to cisplatin. On the other hand, overexpression of NAPA increased resistance to cisplatin by reducing cisplatin-induced ER stress and apoptosis. The modulatory effects of shNAPA required the tumor suppressor p53 since the effects of NAPA knockdown were reduced by the p53 inhibitor PFT-alpha and in H1299 cells which are p53-null. A partial reversal of cisplatin resistance was also observed in cisplatin-resistant HeLa cells following knockdown of NAPA. Our results also indicated that calpain is required for ER-mediated apoptosis. Importantly, combined cisplatin/shNAPA treatment suppressed tumor growth in vivo in xenograph experiments performed in nude mice. Taken together, these observations suggest that NAPA represents a target of cisplatin, and that knockdown of NAPA may improve cisplatin-based cancer therapy.

  11. Multifunctional oval-shaped gold-nanoparticle-based selective detection of breast cancer cells using simple colorimetric and highly sensitive two-photon scattering assay.

    Science.gov (United States)

    Lu, Wentong; Arumugam, Sri Ranjini; Senapati, Dulal; Singh, Anant K; Arbneshi, Tahir; Khan, Sadia Afrin; Yu, Hongtao; Ray, Paresh Chandra

    2010-03-23

    Breast cancer is the most common cancer among women, and it is the second leading cause of cancer deaths in women today. The key to the effective and ultimately successful treatment of diseases such as cancer is early and accurate diagnosis. Driven by the need, in this article, we report for the first time a simple colorimetric and highly sensitive two-photon scattering assay for highly selective and sensitive detection of breast cancer SK-BR-3 cell lines at a 100 cells/mL level using a multifunctional (monoclonal anti-HER2/c-erb-2 antibody and S6 RNA aptamer-conjugated) oval-shaped gold-nanoparticle-based nanoconjugate. When multifunctional oval-shaped gold nanoparticles are mixed with the breast cancer SK-BR-3 cell line, a distinct color change occurs and two-photon scattering intensity increases by about 13 times. Experimental data with the HaCaT noncancerous cell line, as well as with MDA-MB-231 breast cancer cell line, clearly demonstrated that our assay was highly sensitive to SK-BR-3 and it was able to distinguish from other breast cancer cell lines that express low levels of HER2. The mechanism of selectivity and the assay's response change have been discussed. Our experimental results reported here open up a new possibility of rapid, easy, and reliable diagnosis of cancer cell lines by monitoring the colorimetric change and measuring TPS intensity from multifunctional gold nanosystems.

  12. TERRA Expression Levels Do Not Correlate With Telomere Length and Radiation Sensitivity in Human Cancer Cell Lines

    Directory of Open Access Journals (Sweden)

    Alexandra eSmirnova

    2013-05-01

    Full Text Available Mammalian telomeres are transcribed into long non-coding telomeric RNA molecules (TERRA that seem to play a role in the maintenance of telomere stability. In human cells, CpG island promoters drive TERRA transcription and are regulated by methylation. It was suggested that the amount of TERRA may be related to telomere length. To test this hypothesis we measured telomere length and TERRA levels in single clones isolated from five human cell lines: HeLa (cervical carcinoma, BRC-230 (breast cancer, AKG and GK2 (gastric cancers and GM847 (SV40 immortalized skin fibroblasts. We observed great clonal heterogeneity both in TRF (Terminal Restriction Fragment length and in TERRA levels. However, these two parameters did not correlate with each other. Moreover, cell survival to γ-rays did not show a significant variation among the clones, suggesting that, in this cellular system, the intra-population variability in telomere length and TERRA levels does not influence sensitivity to ionizing radiation. This conclusion was supported by the observation that in a cell line in which telomeres were greatly elongated by the ectopic expression of telomerase, TERRA expression levels and radiation sensitivity were similar to the parental HeLa cell line.

  13. miR-320 enhances the sensitivity of human colon cancer cells to chemoradiotherapy in vitro by targeting FOXM1

    Energy Technology Data Exchange (ETDEWEB)

    Wan, Lu-Ying; Deng, Jun; Xiang, Xiao-Jun; Zhang, Ling; Yu, Feng; Chen, Jun; Sun, Zhe; Feng, Miao; Xiong, Jian-Ping, E-mail: jpxiong@medmail.com.cn

    2015-02-06

    Highlights: • miR-320 plays a significant role in chemoresistance. • This role might be attribute to targeting FOXM1. • The Wnt/β-catenin pathway also involves in this chemotherapy sensitivity. - Abstract: miR-320 expression level is found to be down-regulated in human colon cancer. To date, however, its underlying mechanisms in the chemo-resistance remain largely unknown. In this study, we demonstrated that ectopic expression of miR-320 led to inhibit HCT-116 cell proliferation, invasion and hypersensitivity to 5-Fu and Oxaliplatin. Also, knockdown of miR-320 reversed these effects in HT-29 cells. Furthermore, we identified an oncogene, FOXM1, as a direct target of miR-320. In addition, miR-320 could inactive the activity of Wnt/β-catenin pathway. Finally, we found that miR-320 and FOXM1 protein had a negative correlation in colon cancer tissues and adjacent normal tissues. These findings implied that miR-320–FOXM1 axis may overcome chemo-resistance of colon cancer cells and provide a new therapeutic target for the treatment of colon cancer.

  14. Down-regulation of ALKBH2 increases cisplatin sensitivity in H1299 lung cancer cells

    Institute of Scientific and Technical Information of China (English)

    Shuang-shuang WU; Wei XU; Shan LIU; Bo CHEN; Xue-li WANG; Yan WANG; Shi-feng LIU; Jian-qing WU

    2011-01-01

    Aim: To elucidate the combined effect of alkylated DNA repair protein alkB homolog 2 (ALKBH2)-targeting gene therapy and cisplatin (cDDP) chemotherapy on the non-small cell lung cancer (NSCLC)H1299 cell line.Methods: ALKBH2 was down-regulated in H1299 cells by lentivirus-mediated RNA interference (RNAi). Changes in ALKBH2 expression were determined using real-time RT-PCR and Western blotting. Cell viability was evaluated using MTT assay. DNA synthesis in proliferating cells was determined using BrdU incorporation assay. Cell apoptosis was determined using flow cytometry.Results: Lentivirus-mediated ALKBH2 silencing alone did not induce apoptosis or attenuate the growth potential of H1299 cells within five days post-infection. Combined treatment modalities with lentivirus-mediated ALKBH2 down-regulation and cDDP (333 μmol/L)were significantly more potent in inhibiting cell growth and inducing apoptosis than mono-chemotherapy.Conclusion: Combined treatment modalities of ALKBH2 knockdown and cDDP chemotherapy have the potential to improve the efficacy in the treatment of NSCLC.

  15. Downregulation of microRNA-196a enhances the sensitivity of non-small cell lung cancer cells to cisplatin treatment.

    Science.gov (United States)

    Li, Qian; Yang, Zailiang; Chen, Mingyan; Liu, Ying

    2016-04-01

    MicroRNAs (miRNAs or miRs) are a class of small, non-coding RNA molecules that play an important role in the pathogenesis of human diseases through the regulation of gene expression. Although miRNA-196a has been implicated in the progression of human lung cancer, its role in enhancing the sensitivity of non‑small cell lung cancer (NSCLC) cells to cisplatin has not yet been confirmed. The aim of this study was to evaluate the effects of miRNA‑196a on the sensitivity of NSCLC cells to cisplatin in vitro and in vivo. RT-qPCR was used to detect miRNA-196a expression. Synthesized locked nucleic acid (LNA)-anti‑miRNA-196a oligonucleotide was transiently transfected into the SPC‑A‑1 and A549 lung cancer cells to examine the effects of miRNA‑196a on the growth of and colony formation inthe cisplatin‑treated cells. The effects of miRNA-196a on the sensitivity of SPC‑A-1 cells to cisplatin in vivo were determined using BALB/c nude mice. The expression of miRNA‑196a was significantly higher in both the lung cancer tissues and cell lines. The LNA-based knockdown of miRNA-196a significantly inhibited SPC‑A‑1 and A549 cell growth and induced apoptosis. Moreover, the downregulation of miRNA-196a sensitized the SPC‑A‑1 and A549 NSCLC cells to cisplatin in vitro and in vivo, by inducing apoptosis. The findings of this study demonstrate that the administration of cisplatin in combination with miRNA-196a-targeted therapy may be a potential therapeutic strategy for the treatment of NSCLC.

  16. Curcumin Induces Cell Death and Restores Tamoxifen Sensitivity in the Antiestrogen-Resistant Breast Cancer Cell Lines MCF-7/LCC2 and MCF-7/LCC9

    Directory of Open Access Journals (Sweden)

    Min Jiang

    2013-01-01

    Full Text Available Curcumin, a principal component of turmeric (Curcuma longa, has potential therapeutic activities against breast cancer through multiple signaling pathways. Increasing evidence indicates that curcumin reverses chemo-resistance and sensitizes cancer cells to chemotherapy and targeted therapy in breast cancer. To date, few studies have explored its potential antiproliferation effects and resistance reversal in antiestrogen-resistant breast cancer. In this study, we therefore investigated the efficacy of curcumin alone and in combination with tamoxifen in the established antiestrogen-resistant breast cancer cell lines MCF-7/LCC2 and MCF-7/LCC9. We discovered that curcumin treatment displayed anti-proliferative and pro-apoptotic activities and induced cell cycle arrest at G2/M phase. Of note, the combination of curcumin and tamoxifen resulted in a synergistic survival inhibition in MCF-7/LCC2 and MCF-7/LCC9 cells. Moreover, we found that curcumin targeted multiple signals involved in growth maintenance and resistance acquisition in endocrine resistant cells. In our cell models, curcumin could suppress expression of pro-growth and anti-apoptosis molecules, induce inactivation of NF-κB, Src and Akt/mTOR pathways and downregulate the key epigenetic modifier EZH2. The above findings suggested that curcumin alone and combinations of curcumin with endocrine therapy may be of therapeutic benefit for endocrine-resistant breast cancer.

  17. Label-free electrochemical aptasensor constructed by layer-by-layer technology for sensitive and selective detection of cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Tianshu [College of Physics, Jilin University, Changchun, Jilin 130012 (China); State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022 (China); Liu, Jiyang; Gu, Xiaoxiao; Li, Dan [State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022 (China); Wang, Jin, E-mail: jin.wang.1@stonybrook.edu [College of Physics, Jilin University, Changchun, Jilin 130012 (China); State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022 (China); Department of Chemistry, Physics and Applied Mathematics, State University of New York at Stony Brook, Stony Brook, NY 11794-3400 (United States); Wang, Erkang, E-mail: ekwang@ciac.jl.cn [State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022 (China)

    2015-07-02

    Highlights: • Fc-PAH was modified on the surface of graphene to prepare hybid nanocomposite (Fc-PAH-G). • A cytosensor was constructed with Fc-PAH-G, PSS and aptamer AS1411 by LBL technology. • The sensing interface introduced more redox probe and enhanced current signal on electrode. • The sensor showed a detection range of 10–10{sup 6} cells/mL with a detection limit of 10 cells/mL. - Abstract: Here, a cytosensor was constructed with ferrocene-appended poly(allylamine hydrochloride) (Fc-PAH) functionalized graphene (Fc-PAH-G), poly(sodium-p-styrenesulfonate) (PSS) and aptamer (AS1411) by layer-by-layer assembly technology. The hybrid nanocomposite Fc-PAH-G not only brings probes on the electrode and also promotes electron transfer between the probes and the substrate electrode. Meanwhile, LBL technology provides more effective probes to enhance amplified signal for improving the sensitivity of the detection. While AS1411 forming G-quardruplex structure and binding cancer cells, the current response of the sensing electrode decreased due to the insulating properties of cellular membrane. Differential pulse voltammetry (DPV) was performed to investigate the electrochemical detection of HeLa cells attributing to its sensitivity of the current signal change. The as-prepared aptasensor showed a high sensitivity and good stability, a widely detection range from 10 to 10{sup 6} cells/mL with a detection limit as low as 10 cells/mL for the detection of cancer cells.

  18. Proteomic profiling reveals that resveratrol inhibits HSP27 expression and sensitizes breast cancer cells to doxorubicin therapy.

    Directory of Open Access Journals (Sweden)

    José Díaz-Chávez

    Full Text Available The use of chemopreventive natural compounds represents a promising strategy in the search for novel therapeutic agents in cancer. Resveratrol (3,4',5-trans-trihydroxystilbilene is a dietary polyphenol found in fruits, vegetables and medicinal plants that exhibits chemopreventive and antitumor effects. In this study, we searched for modulated proteins with preventive or therapeutic potential in MCF-7 breast cancer cells exposed to resveratrol. Using two-dimensional electrophoresis we found significant changes (FC >2.0; p≤0.05 in the expression of 16 proteins in resveratrol-treated MCF-7 cells. Six down-regulated proteins were identified by tandem mass spectrometry (ESI-MS/MS as heat shock protein 27 (HSP27, translationally-controlled tumor protein, peroxiredoxin-6, stress-induced-phosphoprotein-1, pyridoxine-5'-phosphate oxidase-1 and hypoxanthine-guanine phosphoribosyl transferase; whereas one up-regulated protein was identified as triosephosphate isomerase. Particularly, HSP27 overexpression has been associated to apoptosis inhibition and resistance of human cancer cells to therapy. Consistently, we demonstrated that resveratrol induces apoptosis in MCF-7 cells. Apoptosis was associated with a significant increase in mitochondrial permeability transition, cytochrome c release in cytoplasm, and caspases -3 and -9 independent cell death. Then, we evaluated the chemosensitization effect of increasing concentrations of resveratrol in combination with doxorubicin anti-neoplastic agent in vitro. We found that resveratrol effectively sensitize MCF-7 cells to cytotoxic therapy. Next, we evaluated the relevance of HSP27 targeted inhibition in therapy effectiveness. Results evidenced that HSP27 inhibition using RNA interference enhances the cytotoxicity of doxorubicin. In conclusion, our data indicate that resveratrol may improve the therapeutic effects of doxorubicin in part by cell death induction. We propose that potential modulation of HSP27

  19. PUMA gene transfection can enhance the sensitivity of epirubicin-induced apoptosis of MCF-7 breast cancer cells.

    Science.gov (United States)

    Sun, C-G; Zhuang, J; Teng, W-J; Wang, Z; Du, S-S

    2015-05-29

    We explored whether p53 upregulated modulator of apoptosis (PUMA) gene transfection could enhance the sensitivity of epirubicin-induced apoptosis of MCF-7 breast cancer cells. The liposome-mediated recombinant eukaryotic expression vector PU-MA-pCDNA3 and empty vector plasmid were stably transfected into MCF-7 cells. Epirubicin (0.01-100 μM) was applied to MCF-7, MCF-7/PUMA, and MCF-7/pCDNA3 cells for 72 h. The MTT assay was used to calculate the cell survival rate in each group, and the 50% inhibitory concentration (IC50) was calculated. The IC50 values of epirubicin in MCF-7, MCF-7/PUMA, and MCF-7/pCDNA3 cells were 13 ± 1.4, 1.8 ± 0.2, and 10.7 ± 1.3 μM, respectively. The sensitivity of MCF-7/PUMA cells to epirubicin increased 7.2-fold. Epirubicin induced apoptosis in MCF-7 cells dose-dependently, but MCF-7/PUMA cell-induced apoptosis was more significant compared to controls. Low concentrations of epirubicin (0.1 μM) caused low levels of apoptosis of MCF-7/pCDNA3 (1.15 ± 0.26%) and MCF-7 cells (0.9 ± 0.24%), but significantly induced apoptosis of MCF-7/PUMA cells (6.44 ± 1.46%). High epirubicin concentration (1 μM) induced apoptosis in each group, but the epirubicin MCF-7/PUMA apoptosis rate (35.47 ± 9.36%) was significantly higher than that of MCF-7 (12.6 ± 3.73%) and MCF-7/ pCDNA3 (15.2 ± 5.17%) cells (P PUMA protein expression in MCF-7/PUMA cells was significantly higher than that in MCF-7 and MCF-7/pCDNA3 cells by Western blot analysis. There-fore, stable transfection of PUMA can significantly enhance epirubicin-induced apoptosis sensitivity of MCF-7 breast cancer cells.

  20. Rational design of multifunctional micelles against doxorubicin-sensitive and doxorubicin-resistant MCF-7 human breast cancer cells

    Science.gov (United States)

    Hong, Wei; Shi, Hong; Qiao, Mingxi; Gao, Xiang; Yang, Jie; Tian, Chunlian; Zhang, Dexian; Niu, Shengli; Liu, Mingchun

    2017-01-01

    Even though a tremendous number of multifunctional nanocarriers have been developed to tackle heterogeneous cancer cells, little attention has been paid to elucidate how to rationally design a multifunctional nanocarrier. In this study, three individual functions (active targeting, stimuli-triggered release and endo-lysosomal escape) were evaluated in doxorubicin (DOX)-sensitive MCF-7 cells and DOX-resistant MCF-7/ADR cells by constructing four kinds of micelles with active-targeting (AT-M), passive targeting, pH-triggered release (pHT-M) and endo-lysosomal escape (endoE-M) function, respectively. AT-M demonstrated the strongest cytotoxicity against MCF-7 cells and the highest cellular uptake of DOX due to the folate-mediated endocytosis. However, AT-M failed to exhibit the best efficacy against MCF-7/ADR cells, while endoE-M exhibited the strongest cytotoxicity against MCF-7/ADR cells and the highest cellular uptake of DOX due to the lowest elimination of DOX from the cells. This was attributed to the carrier-facilitated endo-lysosomal escape of DOX, which avoided exocytosis by lysosome secretion, resulting in an effective accumulation of DOX in the cytoplasm. The enhanced elimination of DOX from the MCF-7/ADR cells also accounted for the remarkable decrease in cytotoxicity against the cells of AT-M. Three micelles were further evaluated with MCF-7 cells and MCF-7/ADR-resistant cells xenografted mice model. In accordance with the in vitro results, AT-M and endoE-M demonstrated the strongest inhibition on the MCF-7 and MCF-7/ADR xenografted tumor, respectively. Active targeting and active targeting in combination with endo-lysosomal escape have been demonstrated to be the primary function for a nanocarrier against doxorubicin-sensitive and doxorubicin-resistant MCF-7 cells, respectively. These results indicate that the rational design of multifunctional nanocarriers for cancer therapy needs to consider the heterogeneous cancer cells and the primary function needs

  1. Fibulin-3 negatively regulates ALDH1 via c-MET suppression and increases γ-radiation-induced sensitivity in some pancreatic cancer cell lines

    Energy Technology Data Exchange (ETDEWEB)

    Kim, In-Gyu, E-mail: igkim@kaeri.re.kr [Department of Radiation Biology, Environmental Radiation Research Group, Korea Atomic Energy Research Institute, 989-111 Daedeok-daero, Yuseong-gu, Daejeon 305-353 (Korea, Republic of); Department of Radiation Biotechnology and Applied Radioisotope, Korea University of Science and Technology (UST), 989-111 Daedeok-daero, Yusong-gu, Daejeon 305-353 (Korea, Republic of); Lee, Jae-Ha [Department of Radiation Biology, Environmental Radiation Research Group, Korea Atomic Energy Research Institute, 989-111 Daedeok-daero, Yuseong-gu, Daejeon 305-353 (Korea, Republic of); Department of Radiation Biotechnology and Applied Radioisotope, Korea University of Science and Technology (UST), 989-111 Daedeok-daero, Yusong-gu, Daejeon 305-353 (Korea, Republic of); Kim, Seo-Yoen; Kim, Jeong-Yul [Department of Radiation Biology, Environmental Radiation Research Group, Korea Atomic Energy Research Institute, 989-111 Daedeok-daero, Yuseong-gu, Daejeon 305-353 (Korea, Republic of); Cho, Eun-Wie [Epigenomics Research Center, Korea Research Institute of Bioscience and Biotechnology, 125 Gwahak-ro, Yuseong-gu, Daejeon 305-806 (Korea, Republic of)

    2014-11-21

    Highlights: • FBLN-3 gene was poorly expressed in some pancreatic cancer lines. • FBLN-3 promoter region was highly methylated in some pancreatic cancer cell lines. • FBLN-3 inhibited c-MET activation and expression and reduced cellular level of ALDH1. • FBLN-3/c-Met/ALDH1 axis modulates stemness and EMT in pancreatic cancer cells. - Abstract: Fibulin-3 (FBLN-3) has been postulated to be either a tumor suppressor or promoter depending on the cell type, and hypermethylation of the FBLN-3 promoter is often associated with human disease, especially cancer. We report that the promoter region of the FBLN-3 was significantly methylated (>95%) in some pancreatic cancer cell lines and thus FBLN-3 was poorly expressed in pancreatic cancer cell lines such as AsPC-1 and MiaPaCa-2. FBLN-3 overexpression significantly down-regulated the cellular level of c-MET and inhibited hepatocyte growth factor-induced c-MET activation, which were closely associated with γ-radiation resistance of cancer cells. Moreover, we also showed that c-MET suppression or inactivation decreased the cellular level of ALDH1 isozymes (ALDH1A1 or ALDH1A3), which serve as cancer stem cell markers, and subsequently induced inhibition of cell growth in pancreatic cancer cells. Therefore, forced overexpression of FBLN-3 sensitized cells to cytotoxic agents such as γ-radiation and strongly inhibited the stemness and epithelial to mesenchymal transition (EMT) property of pancreatic cancer cells. On the other hand, if FBLN3 was suppressed in FBLN-3-expressing BxPC3 cells, the results were opposite. This study provides the first demonstration that the FBLN-3/c-MET/ALDH1 axis in pancreatic cancer cells partially modulates stemness and EMT as well as sensitization of cells to the detrimental effects of γ-radiation.

  2. MiR-490-3p sensitizes ovarian cancer cells to cisplatin by directly targeting ABCC2

    Science.gov (United States)

    Tian, Jing; Xu, Yan-Ying; Li, Lian; Hao, Quan

    2017-01-01

    Cisplatin (CDDP) resistance becomes a large obstacle of the beneficial therapy for patients with ovarian cancer. MicroRNAs (miRNAs) act as post-transcriptional regulators of multiple genes’ expression and have been reported to be involved in multi-drug resistance. The purpose of this study was to determine the roles and molecular mechanism of miR-490-3p in the CDDP resistance in ovarian cancer. We found that miR-490-3p was downregulated in CDDP-resistant OVCAR3/CDDP and SKOV3/CDDP cells, which was due to the hypermethylation of miR-490-3p promoter. Functional studies demonstrated that miR-490-3p increased the cell response to CDDP in OVCAR3, SKOV3 and CDDP-resistant cells, while miR-490-3p inhibition resulted in opposite effects. Luciferase assay, real-time PCR and Western blot as well as immunohistochemistry validated that ABCC2 was a direct target of miR-490-3p and miR-490-3p downregulated ABCC2 expression via binding to its 3’UTR. Importantly, silencing of ABCC2 alleviated CDDP resistance induced by miR-490-3p inhibition, while ABCC2 overexpression restored CDDP resistance inhibited by miR-490-3p. In vivo study showed that miR-490-3p enhanced the cytotoxicity of CDDP. Finally, we found that miR-490-3p was downregulated in CDDP-resistant ovarian cancer tissues, while ABCC2 was upregulated. In conclusion, our data indicate that miR-490-3p enhances CDDP sensitivity of ovarian cancer cells through downregulating ABCC2 expression, and suggest that delivery of miR-490-3p might be a potential therapeutic strategy for patients with CDP-resistant ovarian cancer.

  3. Depletion of OLFM4 gene inhibits cell growth and increases sensitization to hydrogen peroxide and tumor necrosis factor-alpha induced-apoptosis in gastric cancer cells

    Directory of Open Access Journals (Sweden)

    Liu Rui-hua

    2012-04-01

    Full Text Available Abstract Background Human olfactomedin 4 (OLFM4 gene is a secreted glycoprotein more commonly known as the anti-apoptotic molecule GW112. OLFM4 is found to be frequently up-regulated in many types of human tumors including gastric cancer and it was believed to play significant role in the progression of gastric cancer. Although the function of OLFM4 has been indicated in many studies, recent evidence strongly suggests a cell or tissue type-dependent role of OLFM4 in cell growth and apoptosis. The aim of this study is to examine the role of gastric cancer-specific expression of OLFM4 in cell growth and apoptosis resistance. Methods OLFM4 expression was eliminated by RNA interference in SGC-7901 and MKN45 cells. Cell proliferation, anchorage-independent growth, cell cycle and apoptosis were characterized in vitro. Tumorigenicity was analyzed in vivo. The apoptosis and caspase-3 activation in response to hydrogen peroxide (H2O2 or tumor necrosis factor-alpha (TNF α were assessed in the presence or absence of caspase inhibitor Z-VAD-fmk. Results The elimination of OLFM4 protein by RNA interference in SGC-7901 and MKN45 cells significantly inhibits tumorigenicity both in vitro and in vivo by induction of cell G1 arrest (all P 2O2 or TNF α-induced apoptosis and caspase-3 activity (all P 2O2 or TNF α-induced apoptosis in OLFM4 knockdown cells (all P Conclusion Our study suggests that depletion of OLFM4 significantly inhibits tumorigenicity of the gastric cancer SGC-7901 and MKN45 cells. Blocking OLFM4 expression can sensitize gastric cancer cells to H2O2 or TNF α treatment by increasing caspase-3 dependent apoptosis. A combination strategy based on OLFM4 inhibition and anticancer drugs treatment may provide therapeutic potential in gastric cancer intervention.

  4. Homozygous mdm2 SNP309 cancer cells with compromised transcriptional elongation at p53 target genes are sensitive to induction of p53-independent cell death.

    Science.gov (United States)

    Rosso, Melissa; Polotskaia, Alla; Bargonetti, Jill

    2015-10-27

    A single nucleotide polymorphism (T to G) in the mdm2 P2 promoter, mdm2 SNP309, leads to MDM2 overexpression promoting chemotherapy resistant cancers. Two mdm2 G/G SNP309 cancer cell lines, MANCA and A875, have compromised wild-type p53 that co-localizes with MDM2 on chromatin. We hypothesized that MDM2 in these cells inhibited transcription initiation at the p53 target genes p21 and puma. Surprisingly, following etoposide treatment transcription initiation occurred at the compromised target genes in MANCA and A875 cells similar to the T/T ML-1 cell line. In all cell lines tested there was equally robust recruitment of total and initiated RNA polymerase II (Pol II). We found that knockdown of MDM2 in G/G cells moderately increased expression of subsets of p53 target genes without increasing p53 stability. Importantly, etoposide and actinomycin D treatments increased histone H3K36 trimethylation in T/T, but not G/G cells, suggesting a G/G correlated inhibition of transcription elongation. We therefore tested a chemotherapeutic agent (8-amino-adenosine) that induces p53-independent cell death for higher clinically relevant cytotoxicity. We demonstrated that T/T and G/G mdm2 SNP309 cells were equally sensitive to 8-amino-adenosine induced cell death. In conclusion for cancer cells overexpressing MDM2, targeting MDM2 may be less effective than inducing p53-independent cell death.

  5. Sinomenine sensitizes multidrug-resistant colon cancer cells (Caco-2 to doxorubicin by downregulation of MDR-1 expression.

    Directory of Open Access Journals (Sweden)

    Zhen Liu

    Full Text Available Chemoresistance in multidrug-resistant (MDR cells over expressing P-glycoprotein (P-gp encoded by the MDR1 gene, is a major obstacle to successful chemotherapy for colorectal cancer. Previous studies have indicated that sinomenine can enhance the absorption of various P-gp substrates. In the present study, we investigated the effect of sinomenine on the chemoresistance in colon cancer cells and explored the underlying mechanism. We developed multidrug-resistant Caco-2 (MDR-Caco-2 cells by exposure of Caco-2 cells to increasing concentrations of doxorubicin. We identified overexpression of COX-2 and MDR-1 genes as well as activation of the NF-κB signal pathway in MDR-Caco-2 cells. Importantly, we found that sinomenine enhances the sensitivity of MDR-Caco-2 cells towards doxorubicin by downregulating MDR-1 and COX-2 expression through inhibition of the NF-κB signaling pathway. These findings provide a new potential strategy for the reversal of P-gp-mediated anticancer drug resistance.

  6. Nanoparticle induced cell magneto-rotation: monitoring morphology, stress and drug sensitivity of a suspended single cancer cell.

    Directory of Open Access Journals (Sweden)

    Remy Elbez

    Full Text Available Single cell analysis has allowed critical discoveries in drug testing, immunobiology and stem cell research. In addition, a change from two to three dimensional growth conditions radically affects cell behavior. This already resulted in new observations on gene expression and communication networks and in better predictions of cell responses to their environment. However, it is still difficult to study the size and shape of single cells that are freely suspended, where morphological changes are highly significant. Described here is a new method for quantitative real time monitoring of cell size and morphology, on single live suspended cancer cells, unconfined in three dimensions. The precision is comparable to that of the best optical microscopes, but, in contrast, there is no need for confining the cell to the imaging plane. The here first introduced cell magnetorotation (CM method is made possible by nanoparticle induced cell magnetization. By using a rotating magnetic field, the magnetically labeled cell is actively rotated, and the rotational period is measured in real-time. A change in morphology induces a change in the rotational period of the suspended cell (e.g. when the cell gets bigger it rotates slower. The ability to monitor, in real time, cell swelling or death, at the single cell level, is demonstrated. This method could thus be used for multiplexed real time single cell morphology analysis, with implications for drug testing, drug discovery, genomics and three-dimensional culturing.

  7. Targeting of apoptotic pathways by SMAC or BH3 mimetics distinctly sensitizes paclitaxel-resistant triple negative breast cancer cells.

    Science.gov (United States)

    Panayotopoulou, Effrosini G; Müller, Anna-Katharina; Börries, Melanie; Busch, Hauke; Hu, Guohong; Lev, Sima

    2017-02-06

    Standard chemotherapy is the only systemic treatment for triple-negative breast cancer (TNBC), and despite the good initial response, resistance remains a major therapeutic obstacle. Here, we employed a High-Throughput Screen to identify targeted therapies that overcome chemoresistance in TNBC. We applied short-term paclitaxel treatment and screened 320 small-molecule inhibitors of known targets to identify drugs that preferentially and efficiently target paclitaxel-treated TNBC cells. Among these compounds the SMAC mimetics (BV6, Birinapant) and BH3-mimetics (ABT-737/263) were recognized as potent targeted therapy for multiple paclitaxel-residual TNBC cell lines. However, acquired paclitaxel resistance through repeated paclitaxel pulses result in desensitization to BV6, but not to ABT-263, suggesting that short- and long-term paclitaxel resistance are mediated by distinct mechanisms. Gene expression profiling of paclitaxel-residual, -resistant and naïve MDA-MB-231 cells demonstrated that paclitaxel-residual, as opposed to -resistant cells, were characterized by an apoptotic signature, with downregulation of anti-apoptotic genes (BCL2, BIRC5), induction of apoptosis inducers (IL24, PDCD4), and enrichment of TNFα/NF-κB pathway, including upregulation of TNFSF15, coupled with cell-cycle arrest. BIRC5 and FOXM1 downregulation and IL24 induction was also evident in breast cancer patient datasets following taxane treatment. Exposure of naïve or paclitaxel-resistant cells to supernatants of paclitaxel-residual cells sensitized them to BV6, and treatment with TNFα enhanced BV6 potency, suggesting that sensitization to BV6 is mediated, at least partially, by secreted factor(s). Our results suggest that administration of SMAC or BH3 mimetics following short-term paclitaxel treatment could be an effective therapeutic strategy for TNBC, while only BH3-mimetics could effectively overcome long-term paclitaxel resistance.

  8. NAC1 modulates sensitivity of ovarian cancer cells to cisplatin by altering the HMGB1-mediated autophagic response.

    Science.gov (United States)

    Zhang, Y; Cheng, Y; Ren, X; Zhang, L; Yap, K L; Wu, H; Patel, R; Liu, D; Qin, Z-H; Shih, I-M; Yang, J-M

    2012-02-23

    Nucleus accumbens-1 (NAC1), a nuclear factor belonging to the BTB/POZ gene family, is known to have important roles in proliferation and growth of tumor cells and in chemotherapy resistance. Yet, the mechanisms underlying how NAC1 contributes to drug resistance remain largely unclear. We report here that autophagy was involved in NAC1-mediated resistance to cisplatin, a commonly used chemotherapeutic drug in the treatment of ovarian cancer. We found that treatment with cisplatin caused an activation of autophagy in ovarian cancer cell lines, A2780, OVCAR3 and SKOV3. We further demonstrated that knockdown of NAC1 by RNA interference or inactivation of NAC1 by inducing the expression of a NAC1 deletion mutant that contains only the BTB/POZ domain significantly inhibited the cisplatin-induced autophagy, resulting in increased cisplatin cytotoxicity. Moreover, inhibition of autophagy and sensitization to cisplatin by NAC1 knockdown or inactivation were accompanied by induction of apoptosis. To confirm that the sensitizing effect of NAC1 inhibition on the cytotoxicity of cisplatin was attributed to suppression of autophagy, we assessed the effects of the autophagy inhibitors 3-methyladenosine and chloroquine, and small interfering RNAs (siRNAs) targeting beclin 1 or Atg5 on the cytotoxicity of cisplatin. Treatment with 3-methyladenosine, chloroquine or beclin 1 and Atg5-targeted siRNA also enhanced the sensitivity of SKOV3, A2780 and OVCAR3 cells to cisplatin, indicating that suppression of autophagy indeed renders tumor cells more sensitive to cisplatin. Regulation of autophagy by NAC1 was mediated by the high-mobility group box 1 (HMGB1), as the functional status of NAC1 was associated with the expression, translocation and release of HMGB1. The results of our study not only revealed a new mechanism determining cisplatin sensitivity but also identified NAC1 as a novel regulator of autophagy. Thus, the NAC1-mediated autophagy may be exploited as a new target for

  9. SIRT1 Influences the Sensitivity of A549 Non-small Cell Lung Cancer Cell Line to 
Cisplatin via Modulating the Noxa Expression

    Directory of Open Access Journals (Sweden)

    Bin CAO

    2016-02-01

    Full Text Available Background and objective The resistance of non-small cell lung cancer cells to cisplant is a common clinical phenomenon which could induce a poor therapeutic effect and should be difficult problem to be solved. SIRT1 and Noxa expression are associated with the chemotherapy for tumors. The present study focused on how SIRT1 expression influence the senstivity of non-small cell lung cancer cells and dissected the potential mechanism involved with Noxa. Methods The difference of SIRT1 and Noxa expression between A549 cells and A549/DDP cells was detected by real-time quantitative PCR (qRT-PCR and Western blot. SIRT1 targeted siRNA was uesed to inhibit the SIRT1 expression in A549/DDP, after transfection, Cell Titer Blue assay, flow cytometry were performed to analyze the cell viability, cell cycle and cell apoptosis in order to reveal the effect of inhibition of SIRT1 on sensitivity of A549/DDP cells to cisplant. Moreover, the expression changes of Noxa in A549/DDP cells after siRNA treatment were detected by qRT-PCR and Western blot. Results There was a significant difference in senstivity to cisplant between A549 and A549/DDP cells. Compared with A549 cells, the A549/DDP cells showed a higher SIRT1 expression and lower Noxa expression. After transfected with SIRT1 targeted siRNA, the cell viability decreased accompanied with a increasing apoptosis rate, meanwhile, higher percent of G2/M phase was detected after the 4 μg/mL cisplant treatment. Further more, inhibition of SIRT1 could induce the Noxa expression in A549/DDP cells. Conclusion Higher SIRT1 expression may induce resistance to cisplant in A549 cells. SIRT1 inhibition may improve the sensitivity of A549/DDP cells to cisplantin though modulating the Noxa expression.

  10. Efficient inhibition of human telomerase activity by antisense oligonucleotides sensitizes cancer cells to radiotherapy

    Institute of Scientific and Technical Information of China (English)

    Xue-mei JI; Cong-hua XIE; Ming-hao FANG; Fu-xiang ZHOU; Wen-jie ZHANG; Ming-sheng ZHANG; Yun-feng ZHOU

    2006-01-01

    Aim: To investigate the effect of the antisense oligonucleotides (ASODN) specific for human telomerase RNA (hTR) on radio sensitization and proliferation inhibition in human neurogliocytoma cells (U251). Methods: U251 cells were transfected with hTR ASODN or nonspecific oligonucleotides (NSODN). Before and after irradiation of 60Co-γray, telomerase activity was assayed by telomeric repeat amplification protocol (TRAP-PCR-ELISA), and DNA damage and repair were examined by the comet assay. The classical colony assay was used to plot the cell-survival curve, to detect the D0 value. Results: hTR antisense oligonucleotides could downregulate the telomerase activity, increase radiation induced DNA damage and reduce the subsequent repair. Furthermore, it could inhibit the proliferation and decrease the D0 value which demonstrates rising radiosensitivity. However, telomere length was unchanged over a short period of time. Conclusion: These findings suggest that an ASODN-based strategy may be used to develop telomerase inhibitors, which can efficiently sensitize radiotherapy.

  11. Patterns Prediction of Chemotherapy Sensitivity in Cancer Cell lines Using FTIR Spectrum, Neural Network and Principal Components Analysis.

    Science.gov (United States)

    Zendehdel, Rezvan; Masoudi-Nejad, Ali; H Shirazi, Farshad

    2012-01-01

    Drug resistance enables cancer cells to break away from cytotoxic effect of anticancer drugs. Identification of resistant phenotype is very important because it can lead to effective treatment plan. There is an interest in developing classifying models of resistance phenotype based on the multivariate data. We have investigated a vibrational spectroscopic approach in order to characterize a sensitive human ovarian cell line, A2780, and its cisplatin-resistant derivative, A2780-cp. In this study FTIR method have been evaluated via the use of principal components analysis (PCA), ANN (artificial neuronal network) and LDA (linear discriminate analysis). FTIR spectroscopy on these cells in the range of 400-4000 cm(-1) showed alteration in the secondary structure of proteins and a CH stretching vibration. We have found that the ANN models correctly classified more than 95% of the cell lines, while the LDA models with the same data sets could classify 85% of cases. In the process of different ranges of spectra, the best classification of data set in the range of 1000-2000 cm(-1) was done using ANN model, while the data set between 2500-3000 cm(-1) was more correctly classified with the LDA model. PCA of the spectral data also provide a good separation for representing the variety of cell line spectra. Our work supports the promise of ANN analysis of FTIR spectrum as a supervised powerful approach and PCA as unsupervised modeling for the development of automated methods to determine the resistant phenotype of cancer classification.

  12. Systematic assessment of multi-gene predictors of pan-cancer cell line sensitivity to drugs exploiting gene expression data

    Science.gov (United States)

    Nguyen, Linh; Dang, Cuong C; Ballester, Pedro J.

    2017-01-01

    Background: Selected gene mutations are routinely used to guide the selection of cancer drugs for a given patient tumour. Large pharmacogenomic data sets, such as those by Genomics of Drug Sensitivity in Cancer (GDSC) consortium, were introduced to discover more of these single-gene markers of drug sensitivity. Very recently, machine learning regression has been used to investigate how well cancer cell line sensitivity to drugs is predicted depending on the type of molecular profile. The latter has revealed that gene expression data is the most predictive profile in the pan-cancer setting. However, no study to date has exploited GDSC data to systematically compare the performance of machine learning models based on multi-gene expression data against that of widely-used single-gene markers based on genomics data. Methods: Here we present this systematic comparison using Random Forest (RF) classifiers exploiting the expression levels of 13,321 genes and an average of 501 tested cell lines per drug. To account for time-dependent batch effects in IC 50 measurements, we employ independent test sets generated with more recent GDSC data than that used to train the predictors and show that this is a more realistic validation than standard k-fold cross-validation. Results and Discussion: Across 127 GDSC drugs, our results show that the single-gene markers unveiled by the MANOVA analysis tend to achieve higher precision than these RF-based multi-gene models, at the cost of generally having a poor recall (i.e. correctly detecting only a small part of the cell lines sensitive to the drug). Regarding overall classification performance, about two thirds of the drugs are better predicted by the multi-gene RF classifiers. Among the drugs with the most predictive of these models, we found pyrimethamine, sunitinib and 17-AAG. Conclusions: Thanks to this unbiased validation, we now know that this type of models can predict in vitro tumour response to some of these drugs. These models

  13. Selective Intracellular Delivery of Recombinant Arginine Deiminase (ADI) Using pH-Sensitive Cell Penetrating Peptides To Overcome ADI Resistance in Hypoxic Breast Cancer Cells.

    Science.gov (United States)

    Yeh, Tzyy-Harn; Chen, Yun-Ru; Chen, Szu-Ying; Shen, Wei-Chiang; Ann, David K; Zaro, Jennica L; Shen, Li-Jiuan

    2016-01-04

    Arginine depletion strategies, such as pegylated recombinant arginine deiminase (ADI-PEG20), offer a promising anticancer treatment. Many tumor cells have suppressed expression of a key enzyme, argininosuccinate synthetase 1 (ASS1), which converts citrulline to arginine. These tumor cells become arginine auxotrophic, as they can no longer synthesize endogenous arginine intracellularly from citrulline, and are therefore sensitive to arginine depletion therapy. However, since ADI-PEG20 only depletes extracellular arginine due to low internalization, ASS1-expressing cells are not susceptible to treatment since they can synthesize arginine intracellularly. Recent studies have found that several factors influence ASS1 expression. In this study, we evaluated the effect of hypoxia, frequently encountered in many solid tumors, on ASS1 expression and its relationship to ADI-resistance in human MDA-MB-231 breast cancer cells. It was found that MDA-MB-231 cells developed ADI resistance in hypoxic conditions with increased ASS1 expression. To restore ADI sensitivity as well as achieve tumor-selective delivery under hypoxia, we constructed a pH-sensitive cell penetrating peptide (CPP)-based delivery system to carry ADI inside cells to deplete both intra- and extracellular arginine. The delivery system was designed to activate the CPP-mediated internalization only at the mildly acidic pH (6.5-7) associated with the microenvironment of hypoxic tumors, thus achieving better selectivity toward tumor cells. The pH sensitivity of the CPP HBHAc was controlled by recombinant fusion to a histidine-glutamine (HE) oligopeptide, generating HBHAc-HE-ADI. The tumor distribution of HBHAc-HE-ADI was comparable to ADI-PEG20 in a mouse xenograft model of human breast cancer cells in vivo. In addition, HBHAc-HE-ADI showed increased in vitro cellular uptake in cells incubated in a mildly acidic pH (hypoxic conditions) compared to normal pH (normoxic conditions), which correlated with pH-sensitive

  14. SiRNA-mediated IGF-1R inhibition sensitizes human colon cancer SW480 cells to radiation

    Energy Technology Data Exchange (ETDEWEB)

    Yavari, Kamal; Taghikhani, Mohammad; Mesbah-Namin, Seyed A. (Dept. of Clinical Biochemistry, Faculty of Medical Sciences, Tarbiat Modares Univ., Tehran (Iran)); Maragheh, Mohammad Ghannadi (Nuclear Fuel Cycle Research Center, Nuclear Sciences and Technology Research Inst., Tehran (Iran)); Babaei, Mohammad Hosein (Radioisotope Quality Control Center, Nuclear Sciences and Technology Research Inst., Tehran (Iran)); Arfaee, Ali Jabbary; Madani, Hossein; Mirzaei, Hamid Reza (Radiation Oncology Dept., Shohada Hospital, Shahid Beheshti Medical Sciences Univ., Tehran (Iran))

    2010-01-15

    Purpose. Insulin like growth factor receptor 1 (IGF-1R) is well-documented to play a key role in radiation response and tumor radiosensitivity, thus offering an attractive clinic drug target to enhance tumor sensitivity to anti-cancer radiotherapy. Material and methods. Human colon carcinoma SW480 cells were transfected with the specific small interference RNA (siRNA) expression vector (pkD-shRNA-IGF-1R-V2) designed to target IGF-1R mRNA. The expression of IGF-1R mRNA and its protein among the transfected and untransfected cells were detected by semi-quantitative RT-PCR and ELISA assay. The changes in cell radiosensitivity were examined by MTT assay. Results. Transfection of mammalian expression vector pkD containing IGF-1R siRNA was shown to reduce IGF-1R mRNA levels by up to 95%. ELISA assay detected a similar inhibition of IGF-1R protein levels in cells transfected with IGF-1R siRNA. SW480 cells transfected with the expression vector for siRNA significantly rendered cells more sensitive to radiation and the highest radiation enhancement ratio was 2.02 +- 0.08. Conclusion. These data provide the first evidence that specific siRNA fragment (pkD-shRNA-IGF-1R-V2) targeting human IGF-1R mRNA is able to enhance colon cancer radiosensitivity. Also results indicated that, combining IGF-1R siRNA and radiation significantly enhances antitumor efficacy compared with either modality alone

  15. Noxa determines localization and stability of MCL-1 and consequently ABT-737 sensitivity in small cell lung cancer.

    Science.gov (United States)

    Nakajima, W; Hicks, M A; Tanaka, N; Krystal, G W; Harada, H

    2014-02-13

    The sensitivity to ABT-737, a prototype BH3 mimetic drug, varies in a broad range in small cell lung cancer (SCLC) cells. We have previously shown that the expression of Noxa, a BH3-only pro-apoptotic BCL-2 family protein, is the critical determinant of ABT-737 sensitivity. We show here that Noxa regulates the localization and stability of MCL-1, an anti-apoptotic member, which results in modulating ABT-737 sensitivity. Mutations in Noxa within the BH3 domain, the carboxyl terminus mitochondrial targeting domain, or of ubiquitinated lysines not only change the localization and stability of Noxa itself but also affect the mitochondrial localization and phosphorylation/ubiquitination status of MCL-1 and consequently modulate sensitivity to ABT-737. Results of studies utilizing these mutant proteins indicate that Noxa recruits MCL-1 from the cytosol to the mitochondria. Translocation of MCL-1 initiates its phosphorylation and subsequent ubiquitination, which triggers proteasome-mediated degradation. The precise regulatory mechanisms of Noxa/MCL-1 expression and stability could provide alternative targets to modulate apoptosis induced by BH3 mimetic drugs or other chemotherapeutic reagents.

  16. FG020326 Sensitized Multidrug Resistant Cancer Cells to Docetaxel-Mediated Apoptosis via Enhancement of Caspases Activation

    Directory of Open Access Journals (Sweden)

    Li-Wu Fu

    2012-05-01

    Full Text Available Apoptotic resistance is the main obstacle for treating cancer patients with chemotherapeutic drugs. Multidrug resistance (MDR is often characterized by the expression of P-glycoprotein (P-gp, a 170-KD ATP-dependent drug efflux protein. Functional P-gp can confer resistance to activate caspase-8 and -3 dependent apoptosis induced by a range of different stimuli, including tumor necrosis and chemotherapeutic drugs such as docetaxel and vincristine. We demonstrated here that comparison of sensitive KB cells, P-gp positive (P-gp+ve KBv200 cells were extremely resistant to apoptosis induced by docetaxel. FG020326, a pharmacological inhibitor of P-gp function, could enhance concentration-dependently the effect of docetaxel on cell apoptosis and sensitize caspase-8, -9 and -3 activation in P-gp overexpressing KBv200 cells, but not in KB cells. Therefore, the enhancement of caspase-8, -9 and -3 activation induced by docetaxel may be one of the key mechanisms of the reversal of P-gp mediated docetaxel resistance by FG020326.

  17. Sensitization of Radioresistant Prostate Cancer Cells by Resveratrol Isolated from Arachis hypogaea Stems

    Science.gov (United States)

    Kao, Min-Chuan; Lo, U-Ging; Lin, Li-Chiung; Lin, Chun-Jung; Chang, Sheau-Jiun; Chen, Chia-Chang; Hsieh, Jer-Tsong; Lin, Ho; Tang, Chih-Hsin; Lai, Chih-Ho

    2017-01-01

    Resveratrol (RV, 3,4ʹ,5-trihydroxystilbene) is naturally produced by a wide variety of plants including grapes and peanuts (Arachis hypogaea). However, the yield of RV from peanut stem and its potential radiosensitizing effects in prostate cancer (PCa) have not been well investigated. In this study, we characterized RV in peanut stem extract (PSE) for the first time and showed that both RV and PSE dose-dependently induced cell death in DOC-2/DAB2 interactive protein (DAB2IP)-deficient PCa cells with the radioresistant phenotype. Furthermore, the combination of radiation with either RV or PSE induced the death of radioresistant PCa cells through delayed repair of radiation-induced DNA double-strand break (DSB) and prolonged G2/M arrest, which induced apoptosis. The administration of RV and PSE effectively enhanced radiation therapy in the shDAB2IP PCa xenograft mouse model. These results demonstrate the promising synergistic effect of RV and PSE combined with radiation in the treatment of radioresistant PCa. PMID:28081154

  18. Targeting FLIP and Mcl-1 using a combination of aspirin and sorafenib sensitizes colon cancer cells to TRAIL

    NARCIS (Netherlands)

    Pennarun, Bodvael; Kleibeuker, Jan H.; Boersma-van Ek, Wytske; Kruyt, Frank A. E.; Hollema, Harry; de Vries, Elisabeth G. E.; de Jong, Steven

    2013-01-01

    The multikinase inhibitor sorafenib is highly effective against certain types of cancer in the clinic and prevents colon cancer cell proliferation in vitro. Non-steroidal anti-inflammatory drugs, such as acetylsalicylic acid (aspirin), have shown activity against colon cancer cells. The aims of this

  19. Ribavirin restores ESR1 gene expression and tamoxifen sensitivity in ESR1 negative breast cancer cell lines

    Directory of Open Access Journals (Sweden)

    Sappok Anne

    2011-12-01

    Full Text Available Abstract Tumor growth is estrogen independent in approximately one-third of all breast cancers, which makes these patients unresponsive to hormonal treatment. This unresponsiveness to hormonal treatment may be explained through the absence of the estrogen receptor alpha (ESR1. The ESR1 gene re-expression through epigenetic modulators such as DNA methyltransferase inhibitors and/or histone deacetylase inhibitors restores tamoxifen sensitivity in ESR1 negative breast cancer cell lines and opens new treatment horizons in patients who were previously associated with a poor prognosis. In the study presented herein, we tested the ability of ribavirin, which shares some structural similarities with the DNA-methyltransferase inhibitor 5-azacytidine and which is widely known as an anti-viral agent in the treatment of hepatitis C, to restore ESR1 gene re-expression in ESR1 negative breast cancer cell lines. In our study we identified ribavirin to restore ESR1 gene re-expression alone and even more in combination with suberoylanilide hydroxamic acid (SAHA - up to 276 fold induction. Ribavirin and analogs could pave the way to novel translational research projects that aim to restore ESR1 gene re-expression and thus the susceptibility to tamoxifen-based endocrine treatment strategies.

  20. Arctigenin suppresses unfolded protein response and sensitizes glucose deprivation-mediated cytotoxicity of cancer cells.

    Science.gov (United States)

    Sun, Shengrong; Wang, Xiong; Wang, Changhua; Nawaz, Ahmed; Wei, Wen; Li, Juanjuan; Wang, Lijun; Yu, De-Hua

    2011-01-01

    The involvement of unfolded protein response (UPR) activation in tumor survival and resistance to chemotherapies suggests a new anticancer strategy targeting UPR pathway. Arctigenin, a natural product, has been recently identified for its antitumor activity with selective toxicity against cancer cells under glucose starvation with unknown mechanism. Here we found that arctigenin specifically blocks the transcriptional induction of two potential anticancer targets, namely glucose-regulated protein-78 (GRP78) and its analog GRP94, under glucose deprivation, but not by tunicamycin. The activation of other UPR pathways, e.g., XBP-1 and ATF4, by glucose deprivation was also suppressed by arctigenin. A further transgene experiment showed that ectopic expression of GRP78 at least partially rescued arctigenin/glucose starvation-mediated cell growth inhibition, suggesting the causal role of UPR suppression in arctigenin-mediated cytotoxicity under glucose starvation. These observations bring a new insight into the mechanism of action of arctigenin and may lead to the design of new anticancer therapeutics.

  1. Carcinoma-associated fibroblasts affect sensitivity to oxaliplatin and 5FU in colorectal cancer cells.

    Science.gov (United States)

    Gonçalves-Ribeiro, Samuel; Díaz-Maroto, Natalia Guillen; Berdiel-Acer, Mireia; Soriano, Antonio; Guardiola, Jordi; Martínez-Villacampa, Mercedes; Salazar, Ramon; Capellà, Gabriel; Villanueva, Alberto; Martínez-Balibrea, Eva; Molleví, David G

    2016-09-13

    The importance of tumor microenvironment (TME) as a relevant contributor to cancer progression and its role in the development of de novo resistance to targeted therapies has become increasingly apparent. However, the mechanisms of microenvironment-mediated drug resistance for nonspecific conventional chemotherapeutic agents, such as platinum compounds or antimetabolites, are still unclear.Here we describe a mechanism induced by soluble factors released by carcinoma-associated fibroblasts (CAFs) that induce the translocation of AKT, Survivin and P38 to the nucleus of tumor cells. These changes are guided to ensure DNA repair and the correct entrance and exit from mitosis in the presence of chemotherapy. We used conditioned media (CM) from normal-colonic fibroblasts and paired CAFs to assess dose response curves of oxaliplatin and 5-fluorouracil, separately or combined, compared with standard culture medium. We also evaluated a colony-forming assay and cell death to demonstrate the protective role of CAF-CM. Immunofluorescence confirmed the translocation of AKT, P38 and Survivin to the nucleus induced by CAF-soluble factors. We also have shown that STAT3 or P38 inhibition provides a promising strategy for overcoming microenvironment-mediated resistance. Conversely, pharmacologic AKT inhibition induces an antagonistic effect that relieves a cMET and STAT3-mediated compensatory feedback that might explain the failure of AKT inhibitors in the clinic so far.

  2. Co-treatment with the anti-malarial drugs mefloquine and primaquine highly sensitizes drug-resistant cancer cells by increasing P-gp inhibition.

    Science.gov (United States)

    Kim, Ju-Hwa; Choi, Ae-Ran; Kim, Yong Kee; Yoon, Sungpil

    2013-11-22

    The purpose of this study was to identify conditions that will increase the sensitivity of resistant cancer cells to anti-mitotic drugs. Currently, atovaquine (ATO), chloroquine (CHL), primaquine (PRI), mefloquine (MEF), artesunate (ART), and doxycycline (DOY) are the most commonly used anti-malarial drugs. Herein, we tested whether anti-malarial drugs can sensitize drug-resistant KBV20C cancer cells. None of the six tested anti-malarial drugs was found to better sensitize the drug-resistant cells compared to the sensitive KB cells. With an exception of DOY, all other anti-malarial drugs tested could sensitize both KB and KBV20C cells to a similar extent, suggesting that anti-malarial drugs could be used for sensitive as well as resistant cancer cells. Furthermore, we examined the effects of anti-malarial drugs in combination with an antimitotic drug, vinblastine (VIN) on the sensitisation of resistant KBV20C cells. Using viability assay, microscopic observation, assessment of cleaved PARP, and Hoechst staining, we identified that two anti-malarial drugs, PRI and MEF, highly sensitized KBV20C-resistant cells to VIN treatment. Moreover, PRI- or MEF-induced sensitisation was not observed in VIN-treated sensitive KB parent cells, suggesting that the observed effect is specific to resistant cancer cells. We demonstrated that the PRI and MEF sensitisation mechanism mainly depends on the inhibition of p-glycoprotein (P-gp). Our findings may contribute to the development of anti-malarial drug-based combination therapies for patients resistant to anti-mitotic drugs.

  3. Methylseleninic acid sensitizes Notch3-activated OVCA429 ovarian cancer cells to carboplatin

    Science.gov (United States)

    Ovarian cancer, the deadliest of gynecologic cancers, is usually diagnosed at advanced stage due to invalidated screening test and non-specific symptoms presented. Although carboplatin has been popular for treating ovarian cancer for decades, patients eventually develop resistance to this platinum-c...

  4. Lunasin Sensitivity in Non-Small Cell Lung Cancer Cells Is Linked to Suppression of Integrin Signaling and Changes in Histone Acetylation

    Directory of Open Access Journals (Sweden)

    Junichi Inaba

    2014-12-01

    Full Text Available Lunasin is a plant derived bioactive peptide with both cancer chemopreventive and therapeutic activity. We recently showed lunasin inhibits non-small cell lung cancer (NSCLC cell proliferation in a cell-line-specific manner. We now compared the effects of lunasin treatment of lunasin-sensitive (H661 and lunasin-insensitive (H1299 NSCLC cells with respect to lunasin uptake, histone acetylation and integrin signaling. Both cell lines exhibited changes in histone acetylation, with H661 cells showing a unique increase in H4K16 acetylation. Proximity ligation assays demonstrated lunasin interacted with integrins containing αv, α5, β1 and β3 subunits to a larger extent in the H661 compared to H1299 cells. Moreover, lunasin specifically disrupted the interaction of β1 and β3 subunits with the downstream signaling components phosphorylated Focal Adhesion Kinase (pFAK, Kindlin and Intergrin Linked Kinase in H661 cells. Immunoblot analyses demonstrated lunasin treatment of H661 resulted in reduced levels of pFAK, phosphorylated Akt and phosphorylated ERK1/2 whereas no changes were observed in H1299 cells. Silencing of αv expression in H661 cells confirmed signaling through integrins containing αv is essential for proliferation. Moreover, lunasin was unable to further inhibit proliferation in αv-silenced H661 cells. This indicates antagonism of integrin signaling via αv-containing integrins is an important component of lunasin’s mechanism of action.

  5. Inhibition of glucose turnover by 3-bromopyruvate counteracts pancreatic cancer stem cell features and sensitizes cells to gemcitabine.

    Science.gov (United States)

    Isayev, Orkhan; Rausch, Vanessa; Bauer, Nathalie; Liu, Li; Fan, Pei; Zhang, Yiyao; Gladkich, Jury; Nwaeburu, Clifford C; Mattern, Jürgen; Mollenhauer, Martin; Rückert, Felix; Zach, Sebastian; Haberkorn, Uwe; Gross, Wolfgang; Schönsiegel, Frank; Bazhin, Alexandr V; Herr, Ingrid

    2014-07-15

    According to the cancer stem cell (CSC) hypothesis, the aggressive growth and early metastasis of pancreatic ductal adenocarcinoma (PDA) is due to the activity of CSCs, which are not targeted by current therapies. Otto Warburg suggested that the growth of cancer cells is driven by a high glucose metabolism. Here, we investigated whether glycolysis inhibition targets CSCs and thus may enhance therapeutic efficacy. Four established and 3 primary PDA cell lines, non-malignant cells, and 3 patient-tumor-derived CSC-enriched spheroidal cultures were analyzed by glucose turnover measurements, MTT and ATP assays, flow cytometry of ALDH1 activity and annexin positivity, colony and spheroid formation, western blotting, electrophoretic mobility shift assay, xenotransplantation, and immunohistochemistry. The effect of siRNA-mediated inhibition of LDH-A and LDH-B was also investigated. The PDA cells exhibited a high glucose metabolism, and glucose withdrawal or LDH inhibition by siRNA prevented growth and colony formation. Treatment with the anti-glycolytic agent 3-bromopyruvate almost completely blocked cell viability, self-renewal potential, NF-κB binding activity, and stem cell-related signaling and reverted gemcitabine resistance. 3-bromopyruvate was less effective in weakly malignant PDA cells and did not affect non-malignant cells, predicting minimal side effects. 3-bromopyruvate inhibited in vivo tumor engraftment and growth on chicken eggs and mice and enhanced the efficacy of gemcitabine by influencing the expression of markers of proliferation, apoptosis, self-renewal, and metastasis. Most importantly, primary CSC-enriched spheroidal cultures were eliminated by 3-bromopyruvate. These findings propose that CSCs may be specifically dependent on a high glucose turnover and suggest 3-bromopyruvate for therapeutic intervention.

  6. The lignan, (-)-sesamin reveals cytotoxicity toward cancer cells: pharmacogenomic determination of genes associated with sensitivity or resistance.

    Science.gov (United States)

    Saeed, Mohamed; Khalid, Hassan; Sugimoto, Yoshikazu; Efferth, Thomas

    2014-04-15

    (-)-Sesamin is a lignan present in sesam oil and a number of medicinal plants. It exerts various pharmacological effects, such as prevention of hyperlipidemia, hypertension, and carcinogenesis. Moreover, (-)-sesamin has chemopreventive and anticancer activity in vitro and in vivo. Multidrug resistance (MDR) of tumors leads to fatal treatment outcome in many patients and novel drugs able to kill multidrug-resistant cells are urgently needed. P-glycoprotein (MDR1/ABCB1) is the best known ATP-binding cassette (ABC) drug transporter mediating MDR. ABCB5 is a close relative to ABCB1, which also mediates MDR. We found that the mRNA expressions of ABCB1 and ABCB5 were not related to the 50% inhibition concentrations (IC50) for (-)-sesamin in a panel of 55 cell lines of the National Cancer Institute, USA. Furthermore, (-)-sesamin inhibited ABCB1- or ABCB5-overexpressing cells with similar efficacy than their drug-sensitive parental counterparts. In addition to ABC transporter-mediated MDR, we attempted to identify other molecular determinants of (-)-sesamin resistance. For this reason, we performed COMPARE and hierarchical cluster analyses of the transcriptome-wide microarray-based mRNA expression of the NCI cell panel. Twenty-three genes were identified, whose mRNA expression correlated with the IC50 values for (-)-sesamin. These genes code for proteins of different biological functions, i.e. ribosomal proteins, components of the mitochondrial respiratory chain, proteins involved in RNA metabolism, protein biosynthesis, or glucose and fatty acid metabolism. Subjecting this set of genes to cluster analysis showed that the cell lines were assembled in the resulting dendrogram according to their responsiveness to (-)-sesamin. In conclusion, (-)-sesamin is not involved in MDR mediated by ABCB1 or ABCB5 and may be valuable to bypass chemoresistance of refractory tumors. The microarray expression profile, which predicted sensitivity or resistance of tumor cells to (-)-sesamin

  7. Copy number variations of HLA-I and activation of NKp30 pathway determine the sensitivity of gastric cancer cells to the cytotoxicity of natural killer cells.

    Science.gov (United States)

    Xing, R; Li, L; Chen, L; Gao, Z; Wang, H; Li, W; Cui, J; Tian, G; Liang, Q; Yu, J; Sung, J J; Luo, G; Gao, H; Xu, X; Yang, H; Wang, J; Zhang, X; Wang, J M; Huang, J; Yu, Y; Wang, J; Lu, Y

    2016-05-19

    Nude mice are important in vivo model for characterization of cell malignancy behavior; however, many cancer cells fail to form tumors in it. Understanding this defective mechanism may provide novel insights into tumorigenesis and how tumor cells escape innate immunity. Whole-genome sequencing was conducted on two gastric cancer (GC) cells, BGC823 and AGS, which do and do not form tumors in nude mice, to identify their genomic differences relevant to natural killer (NK) cells. We found that the tumorigenic capacity of human GC cell lines was dependent on the recruitment and activation of NK cells in xenograft tumors. We used whole-genome sequence (WGS) on GC cell lines to identify potential genes controlling susceptibility to NK-mediated killing. The tumorigenic cell line BGC823 expressed high levels of HLA-I because of copy gain and was resistant to NK cell killing. In contrast, another cell line AGS expressing low levels of HLA-I with activated NKp30/MAPK/IL-12 (interleukin-12) or IL-2 (interleukin-2) pathway was susceptible to NK lysis. Treatment of tumor bearing mice with systemic administration of IL-12 in combination with intratumor injection of anti-HLA-I antibody significantly increased NK cell recruitment into xenograft tumors, which became sensitive to NK killing, resulting in reduced tumor progression. In human GC specimens, decreased HLA-I expression and increased NK cells surrounding tumor cells were correlated with decreased metastasis potential and better prognosis of patients. Our results provide a mechanistic basis for GC cells to escape NK lysis and a promising prospect of NK immunotherapy for GC cells.

  8. Graphene oxide-encoded Ag nanoshells with single-particle detection sensitivity towards cancer cell imaging based on SERRS.

    Science.gov (United States)

    Yim, DaBin; Kang, Homan; Jeon, Su-Ji; Kim, Hye-In; Yang, Jin-Kyoung; Kang, Tae Wook; Lee, Sangyeop; Choo, Jaebum; Lee, Yoon-Sik; Kim, Jin Woong; Kim, Jong-Ho

    2015-05-21

    Developing ultrasensitive Raman nanoprobes is one of the emerging interests in the field of biosensing and bioimaging. Herein, we constructed a new type of surface-enhanced resonance Raman scattering nanoprobe composed of an Ag nanoshell as a surface-enhanced Raman scattering-active nanostructure, which was encapsulated with 4,7,10-trioxa-1,13-tridecanediamine-functionalized graphene oxide as an ultrasensitive Raman reporter exhibiting strong resonance Raman scattering including distinct D and G modes. The designed nanoprobe was able to produce much more intense and simpler Raman signals even at a single particle level than the Ag nanoshell bearing a well-known Raman reporter, which is beneficial for the sensitive detection of a target in a complex biological system. Finally, this ultrasensitive nanoprobe successfully demonstrated its potential for bioimaging of cancer cells using Raman spectroscopy.

  9. ATM Expression Predicts Veliparib and Irinotecan Sensitivity in Gastric Cancer by Mediating P53-Independent Regulation of Cell Cycle and Apoptosis.

    Science.gov (United States)

    Subhash, Vinod Vijay; Tan, Shi Hui; Yeo, Mei Shi; Yan, Fui Leng; Peethala, Praveen C; Liem, Natalia; Krishnan, Vaidehi; Yong, Wei Peng

    2016-12-01

    Identification of synthetically lethal cellular targets and synergistic drug combinations is important in cancer chemotherapy as they help to overcome treatment resistance and increase efficacy. The Ataxia Telangiectasia Mutated (ATM) kinase is a nuclear protein that plays a major role in the initiation of DNA repair signaling and cell-cycle check points during DNA damage. Although ATM was shown to be associated with poor prognosis in gastric cancer, its implications as a predictive biomarker for cancer chemotherapy remain unexplored. The present study evaluated ATM-induced synthetic lethality and its role in sensitization of gastric cancer cells to PARP and TOP1 inhibitors, veliparib (ABT-888) and irinotecan (CPT-11), respectively. ATM expression was detected in a panel of gastric cell lines, and the IC50 against each inhibitors was determined. The combinatorial effect of ABT-888 and CPT-11 in gastric cancer cells was also determined both in vitro and in vivo ATM deficiency was found to be associated with enhanced sensitivity to ABT-888 and CPT-11 monotherapy, hence suggesting a mechanism of synthetic lethality. Cells with high ATM expression showed reduced sensitivity to monotherapy; however, they showed a higher therapeutic effect with ABT-888 and CPT-11 combinatorial therapy. Furthermore, ATM expression was shown to play a major role in cellular homeostasis by regulating cell-cycle progression and apoptosis in a P53-independent manner. The present study highlights the clinical utility of ATM expression as a predictive marker for sensitivity of gastric cancer cells to PARP and TOP1 inhibition and provides a deeper mechanistic insight into ATM-dependent regulation of cellular processes. Mol Cancer Ther; 15(12); 3087-96. ©2016 AACR.

  10. A Blockade of IGF Signaling Sensitizes Human Ovarian Cancer Cells to the Anthelmintic Niclosamide-Induced Anti-Proliferative and Anticancer Activities

    Directory of Open Access Journals (Sweden)

    Youlin Deng

    2016-08-01

    Full Text Available Background/Aims: Ovarian cancer is the most lethal gynecologic malignancy, and there is an unmet clinical need to develop new therapies. Although showing promising anticancer activity, Niclosamide may not be used as a monotherapy. We seek to investigate whether inhibiting IGF signaling potentiates Niclosamide's anticancer efficacy in human ovarian cancer cells. Methods: Cell proliferation and migration are assessed. Cell cycle progression and apoptosis are analyzed by flow cytometry. Inhibition of IGF signaling is accomplished by adenovirus-mediated expression of siRNAs targeting IGF-1R. Cancer-associated pathways are assessed using pathway-specific reporters. Subcutaneous xenograft model is used to determine anticancer activity. Results: We find that Niclosamide is highly effective on inhibiting cell proliferation, cell migration, and cell cycle progression, and inducing apoptosis in human ovarian cancer cells, possibly by targeting multiple signaling pathways involved in ELK1/SRF, AP-1, MYC/MAX and NFkB. Silencing IGF-1R exert a similar but weaker effect than that of Niclosamide's. However, silencing IGF-1R significantly sensitizes ovarian cancer cells to Niclosamide-induced anti-proliferative and anticancer activities both in vitro and in vivo. Conclusion: Niclosamide as a repurposed anticancer agent may be more efficacious when combined with agents that target other signaling pathways such as IGF signaling in the treatment of human cancers including ovarian cancer.

  11. The Mechanism of Gefitinib Resistance Induced by Hepatocyte Growth Factor 
in Sensitive Non-small Cell Lung Cancer Cells in Vitro

    Directory of Open Access Journals (Sweden)

    Xianglan XUAN

    2013-01-01

    Full Text Available Background and objective Previous studies have reported that Met might be related to gefitinib resistance in non-small cell lung cancer (NSCLC. The present study aims to explore the mechanism of hepatocyte growth factor (HGF-induced gefitinib resistance in different gene types of sensitive NSCLC in vitro. Methods The PC-9 and H292 cell lines were chosen and induced by HGF. The cell survival was measured using MTT assay, the cell cycle distribution was measured using PI assay, and cell apoptosis with an Annexin V-PE assay, respectively. The c-Met and p-Met protein expression was determined via Western blot analysis. Results Gefitinib inhibited the growth of PC-9 and H292 cells in a dose-dependent manner. The concentration-survival curves of both cell lines shifted to the right when induced with HGF. HGF did not affect PC-9 and H292 cell proliferation. The cell also had a higher cell survival rate when treated with HGF and gefitinib compared with that under gefitinib alone (P<0.05. The apoptotic rate and cell cycle progression showed no significant difference between the HG and G group (P>0.05. HGF stimulated Met phosphorylation in the PC-9 and H292 cells. Gefitinib inhibited the HGF-induced Met phosphorylation in PC-9 cells, but not in H292 cells. Conclusion HGF induces gefitinib resistance in PC-9 and H292 cells. HGF-induced Met phosphorylation may be an important mechanism of gefitinib resistance in sensitive NSCLC.

  12. Sensitization of prostate cancer cell lines to 5-fluorocytosine induced by a replication incompetent adenoviral vector carrying a cytosine deaminase transcription unit

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    AIM: To investigate the efficiency of cytosine deaminase adenoviral/5-fluorocytosine system on prostate cancer cell lines. METHODS: Cell culture, infectivity test and sensitivity test, observing the bystander effect and animal model experiment were carried out. RESULTS: All the established prostate cancer cell lines were eventually infectable, but ratio of vector/cell and time of exposed at which infection occurs was dependent on the cell lines. The expression of transfered cytosine deaminase gene peaked at different days, but persisted beyond 11 days. The prostate cell lines were sensitized to the 5-fluorocytosine by infection with the cytosine deaminase gene adenoviral vector, and only 5% of the LNCap and 10% of the RM-1 cells infected were required for 100% cell death. In the animal model, there was significant eradiation of tumor growth at the ratio of 400 vector particles/cell and with the systematic treatment of 5-fluorocytosine. CONCLUSION: The adenoviral vector carrying a cytosine deaminase transcription unit can sensitize the prostate cancer cell lines to 5-fluorocytosine, and the system can significantly inhibit the growth of prostatic tumor in mice.

  13. Quantum dot-based quantification revealed differences in subcellular localization of EGFR and E-cadherin between EGFR-TKI sensitive and insensitive cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Huang Donghai; Su Ling; Peng Xianghong; Zhang Hongzheng; Khuri, Fadlo R; Shin, Dong M; Chen Zhuo [Department of Hematology and Medical Oncology, Winship Cancer Institute, Emory University School of Medicine, Atlanta, GA (United States)], E-mail: gzchen@emory.edu

    2009-06-03

    Nanoparticle quantum dots (QDs) provide sharper and more photostable fluorescent signals than organic dyes, allowing quantification of multiple biomarkers simultaneously. In this study, we quantified the expression of epidermal growth factor receptor (EGFR) and E-cadherin (E-cad) in the same cells simultaneously by using secondary antibody-conjugated QDs with two different emission wavelengths (QD605 and QD565) and compared the cellular distribution of EGFR and E-cad between EGFR-tyrosine kinase inhibitor (TKI)-insensitive and -sensitive lung and head and neck cancer cell lines. Relocalization of EGFR and E-cad upon treatment with the EGFR-TKI erlotinib in the presence of EGF was visualized and analyzed quantitatively. Our results showed that QD-immunocytochemistry (ICC)-based technology can not only quantify basal levels of multiple biomarkers but also track the localization of the biomarkers upon biostimulation. With this new technology we found that in EGFR-TKI-insensitive cells, EGFR and E-cad were located mainly in the cytoplasm; while in sensitive cells, they were found mainly on the cell membrane. After induction with EGF, both EGFR and E-cad internalized to the cytoplasm, but the internalization capability in sensitive cells was greater than that in insensitive cells. Quantification also showed that inhibition of EGF-induced EGFR and E-cad internalization by erlotinib in the sensitive cells was stronger than that in the insensitive cells. These studies demonstrate substantial differences between EGFR-TKI-insensitive and -sensitive cancer cells in EGFR and E-cad expression and localization both at the basal level and in response to EGF and erlotinib. QD-based analysis facilitates the understanding of the features of EGFR-TKI-insensitive versus -sensitive cancer cells and may be used in the prediction of patient response to EGFR-targeted therapy.

  14. Bleomycin induced sensitivity to TRAIL/Apo-2L-mediated apoptosis in human seminomatous testicular cancer cells is correlated with upregulation of death receptors.

    Science.gov (United States)

    Timur, Mujgan; Cort, Aysegul; Ozdemir, Evrim; Sarikcioglu, Sureyya Bilmen; Sanlioglu, Salih; Sanlioglu, Ahter Dilsad; Ozben, Tomris

    2015-01-01

    The most common solid tumor is testicular cancer among young men. Bleomycin is an antitumor antibiotic used for the therapy of testicular cancer. TRAIL is a proapoptotic cytokine that qualified as an apoptosis inducer in cancer cells. Killing cancer cells selectively via apoptosis induction is an encouraging therapeutic strategy in clinical settings. Combination of TRAIL with chemotherapeutics has been reported to enhance TRAIL-mediated apoptosis of different kinds of cancer cell lines. The molecular ground for sensitization of tumour cells to TRAIL by chemotherapeutics might involve upregulation of TRAIL-R1 (TR/1, DR4) and/or TRAIL-R2 (TR/2, DR5) receptors or activation of proapoptotic proteins including caspases. The curative potential of TRAIL to eradicate cancer cells selectively in testicular cancer has not been studied before. In this study, we investigated apoptotic effects of bleomycin, TRAIL, and their combined application in NTera-2 and NCCIT testicular cancer cell lines. We measured caspase 3 levels as an apoptosis indicator, and TRAIL receptor expressions using flow cytometry. Both NTera-2 and NCCIT cells were fairly resistant to TRAIL's apoptotic effect. Incubation of bleomycin alone caused a significant increase in caspase 3 activity in NCCIT. Combined incubation with bleomycin and TRAIL lead to elevated caspase 3 activity in Ntera-2. Exposure to 72 h of bleomycin increased TR/1, TR/2, and TR/3 cell-surface expressions in NTera-2. Elevation in TR/1 cell-surface expression was evident only at 24 h of bleomycin application in NCCIT. It can be concluded that TRAIL death receptor expressions in particular are increased in testicular cancer cells via bleomycin treatment, and TRAIL-induced apoptosis is initiated.

  15. Apoptosis-related molecular differences for response to tyrosin kinase inhibitors in drug-sensitive and drug-resistant human bladder cancer cells

    Directory of Open Access Journals (Sweden)

    Jixia Li

    2013-01-01

    Full Text Available Context: The epidermal growth factor receptor (EGFR family is reportedly overexpressed in bladder cancer, and tyrosine kinaseinhibitors (TKIs have been suggested as treatment. Gefitinib is a selective inhibitor of the EGFR and lapatinib is a dual inhibitor of both the EGFR and HER2 (human EGFR type 2 receptor. Both compounds compete with the binding of adenosine triphosphate (ATP to the tyrosine kinase domain of the respective receptors to inhibit receptor autophosphorylation causing suppression of signal transduction. Unfortunately, resistance to these inhibitors is a major clinical problem. Aims: To compare the apoptosis signaling pathway(s induced by gefitinib and lapatinib, in UM-UC-5 (drug-sensitive and UM-UC-14 (drug-resistant bladder cancer cells and to identify molecular differences that might be useful predictors of their efficacy. Materials and Methods: Cell proliferation, cell cycle and apoptosis assay were used to detect the effect of TKIs on UM-UC-5 and UM-UC-14 cells. Molecular differences for response to TKIs were examined by protein array. Results: TKIs strongly inhibited cell proliferation and induced cell cycle G1 arrest and apoptosis in UM-UC-5 cells. Most notable apoptosis molecular differences included decreased claspin, trail, and survivin by TKIs in the sensitive cells. In contrast, TKIs had no effect on resistant cells. Conclusions: Claspin, trail, and survivin might be used to determine the sensitivity of bladder cancers to TKIs.

  16. TOP1 gene copy numbers in colorectal cancer samples and cell lines and their association to in vitro drug sensitivity

    DEFF Research Database (Denmark)

    Rømer, Maria Unni; Jensen, Niels Frank; Nielsen, Signe Lykke;

    2012-01-01

    Background and aims: A positive relationship between topoisomerase-1 (TOP1) protein and sensitivity towards the TOP1 inhibitor irinotecan has been reported in patients with metastatic colorectal cancer (mCRC). The aim of this study was to analyse TOP1 gene copy number variation in tumor tissue from...... epithelium 84% of the samples demonstrated an increased TOP1 gene copy number and 66% had an increased TOP1/CEN-20 ratio compared to the non-affected mucosa. Sixteen (32%) of the tumors had a ratio = 1.5 and 9 of these had a ratio of = 2.0. A positive association was observed between the TOP1 gene copy...... CRC patients and CRC cell lines with different sensitivities to the TOP1 inhibitor SN-38 and oxaliplatin. Methods: A TOP1 gene probe with a chromosome 20 centromere (CEN-20) reference probe was tested on tumor tissue from 50 stage III CRC patients. Additionally, associations between TOP1/CEN-20 ratio...

  17. miR-337-3p and its targets STAT3 and RAP1A modulate taxane sensitivity in non-small cell lung cancers.

    Directory of Open Access Journals (Sweden)

    Liqin Du

    Full Text Available NSCLC (non-small cell lung cancer often exhibits resistance to paclitaxel treatment. Identifying the elements regulating paclitaxel response will advance efforts to overcome such resistance in NSCLC therapy. Using in vitro approaches, we demonstrated that over-expression of the microRNA miR-337-3p sensitizes NCI-H1155 cells to paclitaxel, and that miR-337-3p mimic has a general effect on paclitaxel response in NSCLC cell lines, which may provide a novel adjuvant strategy to paclitaxel in the treatment of lung cancer. By combining in vitro and in silico approaches, we identified STAT3 and RAP1A as direct targets that mediate the effect of miR-337-3p on paclitaxel sensitivity. Further investigation showed that miR-337-3p mimic also sensitizes cells to docetaxel, another member of the taxane family, and that STAT3 levels are significantly correlated with taxane resistance in lung cancer cell lines, suggesting that endogenous STAT3 expression is a determinant of intrinsic taxane resistance in lung cancer. The identification of a miR-337-3p as a modulator of cellular response to taxanes, and STAT3 and RAP1A as regulatory targets which mediate that response, defines a novel regulatory pathway modulating paclitaxel sensitivity in lung cancer cells, which may provide novel adjuvant strategies along with paclitaxel in the treatment of lung cancer and may also provide biomarkers for predicting paclitaxel response in NSCLC.

  18. ERK inhibition sensitizes cancer cells to oleanolic acid-induced apoptosis through ERK/Nrf2/ROS pathway.

    Science.gov (United States)

    Liu, Jia; Ma, Leina; Chen, Xiao; Wang, Jianxun; Yu, Tao; Gong, Ying; Ma, Aiguo; Zheng, Lanhong; Liang, Hui

    2016-06-01

    Oleanolic acid (OA) is a natural triterpenoid that is widely distributed in edible and medicinal plants. OA exerts anti-tumor activity on a wide range of cancer cells primarily through inducing apoptosis. Dysregulated ERK signaling is closely complicated in the biology of cancer, such as metastasis, proliferation, and survival, and it can be activated by various stimuli. In this study, we found that OA induced the activation of ERK in cancer cells. ERK activation compromised the apoptosis induced by OA. Blocking ERK activation by U0126 or siRNAs was able to potentiate the pro-apoptotic activity of OA on cancer cells. OA was shown to promote ERK-dependent Nrf2 expression in cancer cells, and in turn, Nrf2 expression was able to suppress OA-induced ROS generation. Blockade of Nrf2 expression was able to increase ROS levels and apoptotic death in cancer cells. In conclusion, we provided evidences that ERK activation is a mechanism underlying the resistance of cancer cells to OA-induced apoptosis and targeting ERK is a promising strategy to enhance the anti-tumor efficacy of OA.

  19. Dihydrofolate reductase amplification and sensitization to methotrexate of methotrexate-resistant colon cancer cells

    DEFF Research Database (Denmark)

    Morales Torres, Christina; García, Maria J; Ribas, Maria;

    2009-01-01

    Gene amplification is one of the most frequent manifestations of genomic instability in human tumors and plays an important role in tumor progression and acquisition of drug resistance. To better understand the factors involved in acquired resistance to cytotoxic drugs via gene amplification, we ...... to a second round of treatment if left untreated during a sufficient period of time. [Mol Cancer Ther 2009;8(2):424-32]....

  20. miR-15a/16 Enhances Radiation Sensitivity of Non-Small Cell Lung Cancer Cells by Targeting the TLR1/NF-κB Signaling Pathway

    Energy Technology Data Exchange (ETDEWEB)

    Lan, Fengming [Radiation Oncology Department, PLA Airforce General Hospital, Beijing (China); Radiation Oncology Department, Tianjin Hospital, Tianjin (China); Yue, Xiao [Tianjin Huanhu Hospital, Tianjin Neurosurgery Institute, Tianjin (China); Ren, Gang; Li, Hongqi; Ping, Li; Wang, Yingjie [Radiation Oncology Department, PLA Airforce General Hospital, Beijing (China); Xia, Tingyi, E-mail: xiatingyi1959@163.com [Radiation Oncology Department, PLA Airforce General Hospital, Beijing (China)

    2015-01-01

    Purpose: Many miRNAs have been identified as essential issues and core determining factors in tumor radiation. Recent reports have demonstrated that miRNAs and Toll-like receptors could exert reciprocal effects to control cancer development in various ways. However, a novel role of miR-15a/16 in enhancing radiation sensitivity by directly targeting TLR1 has not been reported, to our knowledge. Methods and Materials: Bioinformatic analyses, luciferase reporter assay, biochemical assays, and subcutaneous tumor establishment were used to characterize the signaling pathways of miRNA-15a/16 in response to radiation treatment. Results: First, an inverse correlation between the expression of miR-15a/16 and TLR1 protein was revealed in non-small cell lung cancer (NSCLC) and normal lung tissues. Next, we corroborated that miR-15a/16 specifically bound to TLR1 3′UTR and inhibited the expression of TLR1 in H358 and A549 cells. Furthermore, miR-15a/16 downregulated the activity of the NF-κB signaling pathway through TLR1. In addition, overexpression of miR-15a/16 inhibited survival capability and increased radiation-induced apoptosis, resulting in enhancement of radiosensitivity in H358 and A549 cells. Finally, subcutaneous tumor bearing NSCLC cells in a nude mice model was established, and the results showed that combined groups (miR-15a/16 + radiation) inhibited tumor growth more significantly than did radiation alone. Conclusions: We mainly elucidate that miRNA-15a/16 can enhance radiation sensitivity by regulating the TLR1/NF-κB signaling pathway and act as a potential therapeutic approach to overcome radioresistance for lung cancer treatment.

  1. The Role of AR- and VDR-Modulated miRNAs in Sensitization of Prostate Cancer Cells to Therapy

    Science.gov (United States)

    2012-10-01

    100 U/mL penicillin and 100 μg/mL streptomycin. Cells were maintained at 37°C in a humi- dified atmosphere of 95% air/5% CO2. For all the experi...Mohler JL, et al. Androgen receptor stabilization in recurrent prostate cancer is associated with hypersensitivity to low androgen. Cancer Res 2001; 61

  2. Lung cancer - small cell

    Science.gov (United States)

    Cancer - lung - small cell; Small cell lung cancer; SCLC ... About 15% of all lung cancer cases are SCLC. Small cell lung cancer is slightly more common in men than women. Almost all cases of SCLC are ...

  3. Alterations in the Noxa/Mcl-1 axis determine sensitivity of small cell lung cancer to the BH3 mimetic ABT-737.

    Science.gov (United States)

    Hauck, Paula; Chao, Bo H; Litz, Julie; Krystal, Geoffrey W

    2009-04-01

    To understand the molecular basis for variable sensitivity to the BH3 mimetic drug ABT-737, the abundance of Bcl-2 family members was assayed in a panel of small cell lung cancer cell lines whose sensitivity varied over a 2-log range. Elevated Noxa and Bcl-2 levels directly correlated with sensitivity to ABT-737, whereas Mcl-1 levels were similar in all cell lines tested regardless of sensitivity. Transgenically enforced expression of Noxa but not Bcl-2 resulted in increased sensitivity to ABT-737 in multiple cell lines. This increase was especially pronounced in the H209 cell line in which expression of Noxa resulted in a proportionate decline in Mcl-1 expression. Although overexpression of Noxa enhanced sensitivity of the H526 and H82 cell lines to ABT-737, it did not result in altered Mcl-1 levels. Similarly, small interfering RNA-mediated knockdown of Noxa expression in the H146 cell line, which increased resistance to ABT-737, did not result in altered Mcl-1 levels. Therefore, three of four cell lines studied failed to show Noxa-mediated regulation of Mcl-1 expression. However, despite failure to regulate Mcl-1 levels, Noxa blocked binding of Bim to Mcl-1 following its release from Bcl-2 by ABT-737. Finally, we observed that a 24-hour incubation of the H526 and WBA cell lines with ABT-737 resulted in increased Noxa expression, suggesting that Noxa may play a direct role in ABT-737-mediated apoptosis. These results indicate that Noxa expression is the critical determinant of ABT-737 sensitivity and loss of Noxa-mediated regulation of Mcl-1 expression may be an important feature of small cell lung cancer biology.

  4. Radiation Sensitization in Cancer Therapy.

    Science.gov (United States)

    Greenstock, Clive L.

    1981-01-01

    Discusses various aspects of radiation damage to biological material, including free radical mechanisms, radiation sensitization and protection, tumor hypoxia, mechanism of hypoxic cell radiosensitization, redox model for radiation modification, sensitizer probes of cellular radiation targets, pulse radiolysis studies of free radical kinetics,…

  5. Impact of the putative cancer stem cell markers and growth factor receptor expression on the sensitivity of ovarian cancer cells to treatment with various forms of small molecule tyrosine kinase inhibitors and cytotoxic drugs

    Science.gov (United States)

    Puvanenthiran, Soozana; Essapen, Sharadah; Seddon, Alan M.; Modjtahedi, Helmout

    2016-01-01

    Increased expression and activation of human epidermal growth factor receptor (EGFR) and HER-2 have been reported in numerous cancers. The aim of this study was to determine the sensitivity of a large panel of human ovarian cancer cell lines (OCCLs) to treatment with various forms of small molecule tyrosine kinase inhibitors (TKIs) and cytotoxic drugs. The aim was to see if there was any association between the protein expression of various biomarkers including three putative ovarian cancer stem cell (CSC) markers (CD24, CD44, CD117/c-Kit), P-glycoprotein (P-gp), and HER family members and response to treatment with these agents. The sensitivity of 10 ovarian tumour cell lines to the treatment with various forms of HER TKIs (gefitinib, erlotinib, lapatinib, sapitinib, afatinib, canertinib, neratinib), as well as other TKIs (dasatinib, imatinib, NVP-AEW541, crizotinib) and cytotoxic agents (paclitaxel, cisplatin and doxorubicin), as single agents or in combination, was determined by SRB assay. The effect on these agents on the cell cycle distribution, and downstream signaling molecules and tumour migration were determined using flow cytometry, western blotting, and the IncuCyte Clear View cell migration assay respectively. Of the HER inhibitors, the irreversible pan-TKIs (canertinib, neratinib and afatinib) were the most effective TKIs for inhibiting the growth of all ovarian cancer cells, and for blocking the phosphorylation of EGFR, HER-2, AKT and MAPK in SKOV3 cells. Interestingly, while the majority of cancer cells were highly sensitive to treatment with dasatinib, they were relatively resistant to treatment with imatinib (i.e., IC50 >10 μM). Of the cytotoxic agents, paclitaxel was the most effective for inhibiting the growth of OCCLs, and of various combinations of these drugs, only treatment with a combination of NVP-AEW541 and paclitaxel produced a synergistic or additive anti-proliferative effect in all three cell lines examined (i.e., SKOV3, Caov3, ES2

  6. Differential sensitivity of hormone-responsive and unresponsive human prostate cancer cells (LNCaP) to tumor necrosis factor

    NARCIS (Netherlands)

    X. Zhao (X.); G.J. van Steenbrugge (Gert Jan); F.H. Schröder (Fritz)

    1992-01-01

    textabstractTwo sublines, the hormone-sensitive LNCaP-FGC and the insensitive LNCaP-r (resistant) carcinoma cell lines, originating from the parental human prostatic carcinoma cell line LNCaP were tested for sensitivity to human tumor necrosis factor-α (TNF) using the MTT assay. Irrespective of the

  7. Sensitivity of Breast Cancer Stem Cells to TRA-8 Anti-DR5 Monoclonal Antibody

    Science.gov (United States)

    2013-08-01

    Science 2002-2006 Major: Genetics Graduated May 2006 GPA: 3.5/4.0 Dean’s List 2003, 2004, 2005, 2006 Study Abroad- Universidad Complutense, Madrid...Dickinson-LSRIITM flow cytometer (Chicago, IL). Data was evaluated using FlowJo software (Tree Star, Inc., Ashland, OR). DR5 expression and functional...analysis was carried out with Statistical Analysis Software (SAS) version 9.2. Breast Cancer Res Treat (2012) 133:437–445 439 123 Author’s personal copy

  8. A novel role for peptidylarginine deiminases in microvesicle release reveals therapeutic potential of PAD inhibition in sensitizing prostate cancer cells to chemotherapy

    Directory of Open Access Journals (Sweden)

    Sharad Kholia

    2015-06-01

    Full Text Available Introduction: Protein deimination, defined as the post-translational conversion of protein-bound arginine to citrulline, is carried out by a family of 5 calcium-dependent enzymes, the peptidylarginine deiminases (PADs and has been linked to various cancers. Cellular microvesicle (MV release, which is involved in cancer progression, and deimination have not been associated before. We hypothesize that elevated PAD expression, observed in cancers, causes increased MV release in cancer cells and contributes to cancer progression. Background: We have previously reported that inhibition of MV release sensitizes cancer cells to chemotherapeutic drugs. PAD2 and PAD4, the isozymes expressed in patients with malignant tumours, can be inhibited with the pan-PAD-inhibitor chloramidine (Cl-am. We sought to investigate whether Cl-am can inhibit MV release and whether this pathway could be utilized to further increase the sensitivity of cancer cells to drug-directed treatment. Methods: Prostate cancer cells (PC3 were induced to release high levels of MVs upon BzATP stimulation of P2X7 receptors. Western blotting with the pan-protein deimination antibody F95 was used to detect a range of deiminated proteins in cells stimulated to microvesiculate. Changes in deiminated proteins during microvesiculation were revealed by immunoprecipitation and immunoblotting, and mass spectrometry identified deiminated target proteins with putative roles in microvesiculation. Conclusion: We report for the first time a novel function of PADs in the biogenesis of MVs in cancer cells. Our results reveal that during the stimulation of prostate cancer cells (PC3 to microvesiculate, PAD2 and PAD4 expression levels and the deimination of cytoskeletal actin are increased. Pharmacological inhibition of PAD enzyme activity using Cl-am significantly reduced MV release and abrogated the deimination of cytoskeletal actin. We demonstrated that combined Cl-am and methotrexate (MTX treatment of

  9. Downregulation of ATG14 by EGR1-MIR152 sensitizes ovarian cancer cells to cisplatin-induced apoptosis by inhibiting cyto-protective autophagy.

    Science.gov (United States)

    He, Jun; Yu, Jing-Jie; Xu, Qing; Wang, Lin; Zheng, Jenny Z; Liu, Ling-Zhi; Jiang, Bing-Hua

    2015-01-01

    Cisplatin is commonly used in ovarian cancer treatment by inducing apoptosis in cancer cells as a result of lethal DNA damage. However, the intrinsic and acquired resistance to cisplatin in cancer cells remains a big challenge for improving overall survival. The cyto-protective functions of autophagy in cancer cells have been suggested as a potential mechanism for chemoresistance. Here, we reported MIR152 as a new autophagy-regulating miRNA that plays a role in cisplatin-resistance. We showed that MIR152 expression was dramatically downregulated in the cisplatin-resistant cell lines A2780/CP70, SKOV3/DDP compared with their respective parental cells, and in ovarian cancer tissues associated with cisplatin-resistance. Overexpression of MIR152 sensitized cisplatin-resistant ovarian cancer cells by reducing cisplatin-induced autophagy, enhancing cisplatin-induced apoptosis and inhibition of cell proliferation. A mouse subcutaneous xenograft tumor model using A2780/CP70 cells with overexpressing MIR152 was established and displayed decreased tumor growth in response to cisplatin. We also identified that ATG14 is a functional target of MIR152 in regulating autophagy inhibition. Furthermore, we found that EGR1 (early growth response 1) regulated the MIR152 gene at the transcriptional level. Ectopic expression of EGR1 enhanced efficacy of chemotherapy in A2780/CP70 cells. More importantly, these findings were relevant to clinical cases. Both EGR1 and MIR152 expression levels were significantly lower in ovarian cancer tissues with high levels of ERCC1 (excision repair cross-complementation group 1), a marker for cisplatin-resistance. Collectively, these data provide insights into novel mechanisms for acquired cisplatin-resistance. Activation of EGR1 and MIR152 may be a useful therapeutic strategy to overcome cisplatin-resistance by preventing cyto-protective autophagy in ovarian cancer.

  10. PI3K/Akt inhibition and down-regulation of BCRP re-sensitize MCF7 breast cancer cell line to mitoxantrone chemotherapy

    Directory of Open Access Journals (Sweden)

    Tahereh Komeili-Movahhed

    2015-05-01

    Full Text Available Objective(s:Multidrug resistance (MDR of cancer cells is a major obstacle to successful chemotherapy. Overexpression of breast cancer resistance protein (BCRP is one of the major causes of MDR. In addition, it has been shown that PI3K/Akt signaling pathway involves in drug resistance. Therefore, we evaluated the effects of novel approaches including siRNA directed against BCRP and targeted therapy against PI3K/Akt signaling pathway using LY294002 (LY to re-sensitize breast cancer MCF7 cell line to mitoxantrone (MTX chemotherapy. Materials and Methods: Anticancer effects of MTX, siRNA, and LY alone and in combination were evaluated in MCF7 cells using MTT cytotoxicity assay and flow cytometry analysis of cell cycle distribution and apoptosis induction. Results: MTT and apoptosis assays showed that both MTX and LY inhibited cell proliferation and induced apoptosis in MCF7 cells. Results indicated that inhibition of BCRP by siRNA or PI3K/Akt signaling pathway by LY significantly increased sensitivity of MCF7 cells to antiproliferation and apoptosis induction of MTX. Furthermore, MTX showed G2/M arrest, whereas LY induced G0/G1 arrest in cell cycle distribution of MCF7 cells. Combination of siRNA or LY with MTX chemotherapy significantly increased accumulation of MCF7 cells in the G2/M phase of cell cycle. Conclusion: Combination of MTX chemotherapy with BCRP siRNA and PI3K/Akt inhibition can overcome MDR in breast cancer cells. This study furthermore suggests that novel therapeutic approaches are needed to enhance anticancer effects of available drugs in breast cancer

  11. PI3K/Akt inhibition and down-regulation of BCRP re-sensitize MCF7 breast cancer cell line to mitoxantrone chemotherapy

    Science.gov (United States)

    Komeili-Movahhed, Tahereh; Fouladdel, Shamileh; Barzegar, Elmira; Atashpour, Shekoufeh; Hossein Ghahremani, Mohammad; Nasser Ostad, Seyed; Madjd, Zahra; Azizi, Ebrahim

    2015-01-01

    Objective(s): Multidrug resistance (MDR) of cancer cells is a major obstacle to successful chemotherapy. Overexpression of breast cancer resistance protein (BCRP) is one of the major causes of MDR. In addition, it has been shown that PI3K/Akt signaling pathway involves in drug resistance. Therefore, we evaluated the effects of novel approaches including siRNA directed against BCRP and targeted therapy against PI3K/Akt signaling pathway using LY294002 (LY) to re-sensitize breast cancer MCF7 cell line to mitoxantrone (MTX) chemotherapy. Materials and Methods: Anticancer effects of MTX, siRNA, and LY alone and in combination were evaluated in MCF7 cells using MTT cytotoxicity assay and flow cytometry analysis of cell cycle distribution and apoptosis induction. Results: MTT and apoptosis assays showed that both MTX and LY inhibited cell proliferation and induced apoptosis in MCF7 cells. Results indicated that inhibition of BCRP by siRNA or PI3K/Akt signaling pathway by LY significantly increased sensitivity of MCF7 cells to antiproliferation and apoptosis induction of MTX. Furthermore, MTX showed G2/M arrest, whereas LY induced G0/G1 arrest in cell cycle distribution of MCF7 cells. Combination of siRNA or LY with MTX chemotherapy significantly increased accumulation of MCF7 cells in the G2/M phase of cell cycle. Conclusion: Combination of MTX chemotherapy with BCRP siRNA and PI3K/Akt inhibition can overcome MDR in breast cancer cells. This study furthermore suggests that novel therapeutic approaches are needed to enhance anticancer effects of available drugs in breast cancer. PMID:26124933

  12. Simulating hypoxia-induced acidic environment in cancer cells facilitates mobilization and redox-cycling of genomic copper by daidzein leading to pro-oxidant cell death: implications for the sensitization of resistant hypoxic cancer cells to therapeutic challenges.

    Science.gov (United States)

    Ullah, Mohammad F; Ahmad, Aamir; Bhat, Showket H; Khan, Husain Y; Zubair, Haseeb; Sarkar, Fazlul H; Hadi, Sheikh M

    2016-04-01

    This study was conducted to investigate the mechanism of action involved in the anti-cancer activity of daidzein and identification of cancer specific micro-environment as therapeutic target of this secondary metabolite derived from soy. Our data indicated that daidzein induces cellular DNA breakage, anti-proliferative effects and apoptosis in a concentration-dependent manner. We demonstrated that such a daidzein-induced anti-cancer action involves a copper-dependant pathway in which endogenous copper is mobilized by daidzein and redox-cycled to generate reactive oxygen species which act as an upstream signal leading to pro-oxidant cell death. Further in the context of hypoxia being a resistant factor against standard therapies and that an effect secondary to hypoxia is the intracellular acidification, we show that the anticancer activity of daidzein is modulated positively in acidic pH but copper-specific chelator is still able to inhibit daidzein activity. Moreover, an experimental setup of hypoxia mimic (cobalt chloride) revealed an enhanced sensitivity of cancer cells to the cytotoxic effects of daidzein which was neutralized in the presence of neocuproine. The findings support a paradigm shift from the conventional antioxidant property of dietary isoflavones to molecules capable of initiating a pro-oxidant signaling mediated by reactive oxygen species. Further, the clinical relevance of such an action mechanism in cancer chemoprevention is also proposed. This study identified endogenous copper as a molecular target and acidic pH as a modulating factor for the therapeutic activity of daidzein against cancer. The evidence presented highlights the potential of dietary agents as adjuvants to standard therapeutic regimens.

  13. Disruption of BASIGIN decreases lactic acid export and sensitizes non-small cell lung cancer to biguanides independently of the LKB1 status.

    Science.gov (United States)

    Granja, Sara; Marchiq, Ibtissam; Le Floch, Renaud; Moura, Conceição Souto; Baltazar, Fátima; Pouysségur, Jacques

    2015-03-30

    Most cancers rely on aerobic glycolysis to generate energy and metabolic intermediates. To maintain a high glycolytic rate, cells must efficiently export lactic acid through the proton-coupled monocarboxylate transporters (MCT1/4). These transporters require a chaperone, CD147/BASIGIN (BSG) for trafficking to the plasma membrane and function.To validate the key role of these transporters in lung cancer, we first analysed the expression of MCT1/4 and BSG in 50 non-small lung cancer (NSCLC) cases. These proteins were specifically upregulated in tumour tissues. We then disrupted BSG in three NSCLC cell lines (A549, H1975 and H292) via 'Zinc-Finger Nucleases'. The three homozygous BSG-/- cell lines displayed a low MCT activity (10- to 5-fold reduction, for MCT1 and MCT4, respectively) compared to wild-type cells. Consequently, the rate of glycolysis, compared to the wild-type counterpart, was reduced by 2.0- to 3.5-fold, whereas the rate of respiration was stimulated in BSG-/- cell lines. Both wild-type and BSG-null cells were extremely sensitive to the mitochondria inhibitor metformin/phenformin in normoxia. However, only BSG-null cells, independently of their LKB1 status, remained sensitive to biguanides in hypoxia in vitro and tumour growth in nude mice. Our results demonstrate that inhibiting glycolysis by targeting lactic acid export sensitizes NSCLC to phenformin.

  14. Cancerous epithelial cell lines shed extracellular vesicles with a bimodal size distribution that is sensitive to glutamine inhibition

    Science.gov (United States)

    Santana, Steven Michael; Antonyak, Marc A.; Cerione, Richard A.; Kirby, Brian J.

    2014-12-01

    Extracellular shed vesicles (ESVs) facilitate a unique mode of cell-cell communication wherein vesicle uptake can induce a change in the recipient cell's state. Despite the intensity of ESV research, currently reported data represent the bulk characterization of concentrated vesicle samples with little attention paid to heterogeneity. ESV populations likely represent diversity in mechanisms of formation, cargo and size. To better understand ESV subpopulations and the signaling cascades implicated in their formation, we characterize ESV size distributions to identify subpopulations in normal and cancerous epithelial cells. We have discovered that cancer cells exhibit bimodal ESV distributions, one small-diameter and another large-diameter population, suggesting that two mechanisms may govern ESV formation, an exosome population and a cancer-specific microvesicle population. Altered glutamine metabolism in cancer is thought to fuel cancer growth but may also support metastatic niche formation through microvesicle production. We describe the role of a glutaminase inhibitor, compound 968, in ESV production. We have discovered that inhibiting glutamine metabolism significantly impairs large-diameter microvesicle production in cancer cells.

  15. CDK5 Regulates Paclitaxel Sensitivity in Ovarian Cancer Cells by Modulating AKT Activation, p21Cip1- and p27Kip1-Mediated G1 Cell Cycle Arrest and Apoptosis.

    Directory of Open Access Journals (Sweden)

    Shu Zhang

    Full Text Available Cyclin-dependent kinase 5 (CDK5 is a cytoplasmic serine/ threonine kinase. Knockdown of CDK5 enhances paclitaxel sensitivity in human ovarian cancer cells. This study explores the mechanisms by which CDK5 regulates paclitaxel sensitivity in human ovarian cancers. Multiple ovarian cancer cell lines and xenografts were treated with CDK5 small interfering RNA (siRNA with or without paclitaxel to examine the effect on cancer cell viability, cell cycle arrest and tumor growth. CDK5 protein was measured by immunohistochemical staining of an ovarian cancer tissue microarray to correlate CDK5 expression with overall patient survival. Knockdown of CDK5 with siRNAs inhibits activation of AKT which significantly correlates with decreased cell growth and enhanced paclitaxel sensitivity in ovarian cancer cell lines. In addition, CDK5 knockdown alone and in combination with paclitaxel induced G1 cell cycle arrest and caspase 3 dependent apoptotic cell death associated with post-translational upregulation and nuclear translocation of TP53 and p27(Kip1 as well as TP53-dependent transcriptional induction of p21(Cip1 in wild type TP53 cancer cells. Treatment of HEYA8 and A2780 wild type TP53 xenografts in nu/nu mice with CDK5 siRNA and paclitaxel produced significantly greater growth inhibition than either treatment alone. Increased expression of CDK5 in human ovarian cancers correlates inversely with overall survival. CDK5 modulates paclitaxel sensitivity by regulating AKT activation, the cell cycle and caspase-dependent apoptosis. CDK5 inhibition can potentiate paclitaxel activity in human ovarian cancer cells.

  16. HSP90 inhibition downregulates thymidylate synthase and sensitizes colorectal cancer cell lines to the effect of 5FU-based chemotherapy.

    Science.gov (United States)

    Nagaraju, Ganji Purnachandra; Alese, Olatunji B; Landry, Jerome; Diaz, Roberto; El-Rayes, Bassel F

    2014-10-30

    Cell cycle progression and DNA synthesis are essential steps in cancer cell growth. Thymidylate synthase (TS) is a therapeutic target for 5FU. We tested the hypothesis that HSP90 transcriptional and functional inhibition can inhibit cell cycle progression, downregulate TS levels and sensitize colorectal cancer (CRC) cell lines to the effects of 5FU. Treatment with ganetespib (50 nM) for 24 hours inhibited cyclin D1 and pRb at the transcriptional and translational levels and induced p21, leading to G0/G1 cell cycle arrest in both CRC cell lines (HCT-116 and HT-29). This was associated with downregulation of E2F1 and its target gene TS. In addition, ganetespib inhibited PI3K/Akt and ERK signalling pathways. Similar effects were observed with HSP90 knockdown in both cell lines. Ganetespib sensitized CRC cell lines to the effects of oxaliplatin and 5FU. Similar effects were also observed in tumors from animals treated with ganetespib, oxaliplatin and 5FU. In this study, we present in vitro and animal data supporting that the targeting of HSP90 decreases CRC cell survival and proliferation. Ganetespib sensitizes CRC cell lines to the effects of 5FU-based chemotherapy. Combining HSP90 inhibitors with chemotherapy is a rational approach for future drug development in CRC.

  17. Tumor Suppression and Sensitization to Taxol Induces Apoptosis of EIA in Breast Cancer Cells

    Science.gov (United States)

    2005-06-01

    JG, Losa JH, Sanchez-Arevalo VJ et al. Modulation of PI3K/Akt pathway by Ela omedi- ates sensitivity to cisplatin. Oncogene 2002; 21:7131-7136. 37...ElA. Oncogene 15:953-960. induced JNK/p38 and Bax activation by phosphorylation of ASKI: implica- 54. Viniegra, J. G., J. H. Losa , V. J. Sanchez...3398. 7. Steeg P, Bevilacqua G, Pozzatti R, Liotta LA, Sobel ME. 25. Viniegra JG, Losa JH, Sanchez-Arevalo VJ, et al. Modula- Altered expression of

  18. Suppression of microRNA-31 increases sensitivity to 5-FU at an early stage, and affects cell migration and invasion in HCT-116 colon cancer cells

    Directory of Open Access Journals (Sweden)

    Sun Xiao-Feng

    2010-11-01

    Full Text Available Abstract Background MicroRNAs (miRNAs are endogenously expressed noncoding RNAs with important biological and pathological functions. Although several studies have shown that microRNA-31 (miR-31 is obviously up-regulated in colorectal cancer (CRC, there is no study on the functional roles of miR-31 in CRC. Methods Anti-miR™ miRNA 31 inhibitor (anti-miR-31 is a sequence-specific and chemically modified oligonucleotide to specifically target and knockdown miR-31 molecule. The effect of anti-miR-31 transfection was investigated by real-time PCR. HCT-116p53+/+ and HCT-116p53-/-colon cancer cells were treated by anti-miR-31 with or without 5-fluorouracil (5-FU, cell proliferation was determined by MTT assay; apoptosis was detected by DAPI staining; cell cycle was evaluated by flow cytometry; colony formation, migration and invasion assays were performed to investigate the effect of suppression of miR-31 on the cell lines. Results Real-time PCR results showed that anti-miR-31 was efficiently introduced into the cells and reduced miR-31 levels to 44.1% in HCT-116p53+/+ and 67.8% in HCT-116p53-/-cell line (p = 0.042 and 0.046. MTT results showed that anti-miR-31 alone had no effect on the proliferation of HCT-116p53+/+ or HCT-116p53-/-. However, when combined with 5-FU, anti-miR-31 inhibited the proliferation of the two cell lines as early as 24 h after exposure to 5-FU (p = 0.038 and 0.044. Suppression of miR-31 caused a reduction of the migratory cells by nearly 50% compared with the negative control in both HCT-116p53+/+ and HCT-116p53-/-(p = 0.040 and 0.001. The invasive ability of the cells were increased by 8-fold in HCT-116p53+/+ and 2-fold in HCT-116p53-/- (p = 0.045 and 0.009. Suppression of miR-31 had no effect on cell cycle and colony formation (p > 0.05. Conclusions Suppression of miR-31 increases sensitivity to 5-FU at an early stage, and affects cell migration and invasion in HCT-116 colon cancer cells.

  19. Crude alkaloid extract of Rhazya stricta inhibits cell growth and sensitizes human lung cancer cells to cisplatin through induction of apoptosis

    Directory of Open Access Journals (Sweden)

    Ayman I. Elkady

    2013-01-01

    Full Text Available There is an urgent need to improve the clinical management of non-small cell lung cancer (NSCLC, one of the most frequent causes of cancer-related deaths in men and women worldwide. Rhazya stricta, an important medicinal plant used in traditional Oriental medicine, possesses anti-oxidant, anti-carcinogenic and free radical scavenging properties. This study was done to explore the potential anticancer activity of a crude alkaloid extract of R. stricta (CAERS against the NSCLC line A549. CAERS markedly suppressed the growth of A549 cells and considerably enhanced the anti-proliferative potential of cisplatin. CAERS-mediated inhibition of A549 cell growth correlated with the induction of apoptosis that was accompanied by numerous morphological changes, DNA fragmentation, an increase in the Bax/Bcl-2 ratio, the release of mitochondrial cytochrome c, activation of caspases 3 and 9 and cleavage of poly(ADP-ribose-polymerase. CAERS reduced the constitutive expression of anti-apoptotic proteins (Bcl-2, Bcl-X L, Mcl-1 and Survivin and cell cycle regulating proteins (cyclin D1 and c-Myc, but enhanced expression of the proapoptotic proteins Noxa and BAD. These observations indicate that CAERS induced apoptosis and sensitized NSCLC to cisplatin via a mitochondria-mediated apoptotic pathway. These data provide a rationale for using a combination of CAERS and CDDP to treat NSCLC and other CDDP-resistant tumors.

  20. LeftyA sensitive cytosolic pH regulation and glycolytic flux in Ishikawa human endometrial cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Salker, Madhuri S.; Zhou, Yuetao; Singh, Yogesh [Department of Physiology, University of Tuebingen, 72076 Tuebingen (Germany); Brosens, Jan [Division of Reproductive Health, Warwick Medical School, Clinical Sciences Research Laboratories, University Hospital, Coventry CV2 2DX (United Kingdom); Lang, Florian, E-mail: florian.lang@uni-tuebingen.de [Department of Physiology, University of Tuebingen, 72076 Tuebingen (Germany)

    2015-05-08

    Objective: LeftyA, a powerful regulator of stemness, embryonic differentiation, and reprogramming of cancer cells, counteracts cell proliferation and tumor growth. Key properties of tumor cells include enhanced glycolytic flux, which is highly sensitive to cytosolic pH and thus requires export of H{sup +} and lactate. H{sup +} extrusion is in part accomplished by Na{sup +}/H{sup +} exchangers, such as NHE1. An effect of LeftyA on transport processes has, however, never been reported. The present study thus explored whether LeftyA modifies regulation of cytosolic pH (pHi) in Ishikawa cells, a well differentiated endometrial carcinoma cell model. Methods: NHE1 transcript levels were determined by qRT-PCR, NHE1 protein abundance quantified by Western blotting, pH{sub i} estimated utilizing (2',7'-bis-(2-carboxyethyl)-5-(and-6)-carboxyfluorescein [BCECF] fluorescence, Na{sup +}/H{sup +} exchanger activity from Na{sup +} dependent realkalinization after an ammonium pulse, and lactate concentration in the supernatant utilizing an enzymatic assay and subsequent colorimetry. Results: A 2 h treatment with LeftyA (8 ng/ml) significantly decreased NHE1 transcript levels (by 99.6%), NHE1 protein abundance (by 71%), Na{sup +}/H{sup +} exchanger activity (by 55%), pHi (from 7.22 ± 0.02 to 7.05 ± 0.02), and lactate release (by 41%). Conclusions: LeftyA markedly down-regulates NHE1 expression, Na{sup +}/H{sup +} exchanger activity, pHi, and lactate release in Ishikawa cells. Those effects presumably contribute to cellular reprogramming and growth inhibition. - Highlights: • LeftyA, an inhibitor of tumor growth, reduces Na{sup +}/H{sup +}-exchanger activity by 55%. • LeftyA decreases NHE1 transcripts by 99.6% and NHE1 protein by 71%. • LeftyA decreases cytosolic pH from 7.22 ± 0.02 to 7.05 ± 0.02. • Cytosolic acidification by Lefty A decreases glycolysis by 41%. • Cytosolic acidification by Lefty A compromises energy production of tumor cells.

  1. Monascuspiloin enhances the radiation sensitivity of human prostate cancer cells by stimulating endoplasmic reticulum stress and inducing autophagy.

    Directory of Open Access Journals (Sweden)

    Hui-Wen Chiu

    Full Text Available Prostate cancer is a very common cancer among males. Traditional treatments for prostate cancer have limited efficacy; therefore, new therapeutic strategies and/or new adjuvant drugs must be explored. Red yeast rice (RYR is a traditional food spice made in Asia by fermenting white rice with Monascus purpureus Went yeast. Accumulating evidence indicates that RYR has antitumor activity. In this study, PC-3 cells (human prostate cancer cells were used to investigate the anti-cancer effects of ionizing radiation (IR combined with monascuspiloin (MP, a yellow pigment isolated from Monascus pilosus M93-fermented rice and to determine the underlying mechanisms of these effects in vitro and in vivo. We found that IR combined with MP showed increased therapeutic efficacy when compared with either treatment alone in PC-3 cells. In addition, the combined treatment enhanced DNA damage and endoplasmic reticulum (ER stress. The combined treatment induced primarily autophagy in PC-3 cells, and the cell death that was induced by the combined treatment was chiefly the result of inhibition of the Akt/mTOR signaling pathways. In an in vivo study, the combination treatment showed greater anti-tumor growth effects. These novel findings suggest that the combined treatment could be a potential therapeutic strategy for prostate cancer.

  2. Depletion of CABYR-a/b sensitizes lung cancer cells to TRAIL-induced apoptosis through YAP/p73-mediated DR5 upregulation.

    Science.gov (United States)

    Xiao, Qianqian; Qian, Zunlei; Zhang, Weiqing; Liu, Jin; Hu, Enze; Zhang, Jinsan; Li, Mingying; Wang, Junhao; Kong, Fei; Li, Yunguang; Wang, Rui; Tan, Xiaohua; He, Dacheng; Xiao, Xueyuan

    2016-02-23

    Our previous study revealed that knockdown of CABYR-a/b increases the chemosensitivity of lung cancer cells through inactivation of Akt. Here, we demonstrated that depletion of CABYR-a/b significantly increased DR5 expression and sensitized lung cancer cells to TRAIL-induced apoptosis in vitro and/or in vivo. Importantly, treatment with AD5-10, a DR5-specific agonistic monoclonal antibody, was able to mimic TRAIL-induced apoptosis in CABYR-a/b-silenced cells. Strikingly, we identified that depletion of CABYR-a/b not only increased the expressions of p73 and DR5 but also decreased the phosphorylation of YAP S127. Loss- or gain-of-function studies of YAP and p73 revealed that double deletions of YAP and p73 effectively decreased the expression of DR5 and abolished TRAIL-induced apoptosis in CABYR-a/b knockdown cells. Conversely, the co-overexpression of YAP and p73 promoted the expression of DR5 and sensitized cells to TRAIL-induced apoptosis. Taken together, our results demonstrate that depletion of CABYR-a/b sensitizes lung cancer cells to TRAIL-induced apoptosis through YAP/p73-mediated DR5 upregulation.

  3. Autophagy inhibition sensitizes bladder cancer cells to the photodynamic effects of the novel photosensitizer chlorophyllin e4.

    Science.gov (United States)

    Du, Lihuan; Jiang, Ning; Wang, Guozeng; Chu, Yiwei; Lin, Wei; Qian, Jing; Zhang, Yuanfang; Zheng, Jingcun; Chen, Gang

    2014-04-05

    We previously developed a novel photosensitizer, chlorophyllin e4, and found that chlorophyllin e4 mediated-PDT could kill 5637 and T24 cells by inducing apoptotic cell death. Here, we further investigated the new mechanism of autophagy and determined its relevance to apoptosis in e4-PDT. We demonstrated that chlorophyllin e4 was located in both lysosome and mitochondria, and autophagy also occurred in bladder cancer cells upon e4-PDT. More importantly, autophagy played a pro-survival role, and its inhibition enhanced e4-PDT-associated apoptotic cell death because cells pretreated with the typical autophagy inhibitor either 3-methyladenine or Bafilomycin A1 exhibited much lower cell viability and higher apoptotic cell death. Thus, these data imply that the combination of PDT, when mediated by our new photosensitizer chlorophyllin e4, and an autophagy inhibitor might be a promising approach to the eliminationof non-muscle invasive bladder cancer.

  4. Dye sensitized solar cells.

    Science.gov (United States)

    Wei, Di

    2010-03-16

    Dye sensitized solar cell (DSSC) is the only solar cell that can offer both the flexibility and transparency. Its efficiency is comparable to amorphous silicon solar cells but with a much lower cost. This review not only covers the fundamentals of DSSC but also the related cutting-edge research and its development for industrial applications. Most recent research topics on DSSC, for example, applications of nanostructured TiO(2), ZnO electrodes, ionic liquid electrolytes, carbon nanotubes, graphene and solid state DSSC have all been included and discussed.

  5. Dye Sensitized Solar Cells

    Directory of Open Access Journals (Sweden)

    Di Wei

    2010-03-01

    Full Text Available Dye sensitized solar cell (DSSC is the only solar cell that can offer both the flexibility and transparency. Its efficiency is comparable to amorphous silicon solar cells but with a much lower cost. This review not only covers the fundamentals of DSSC but also the related cutting-edge research and its development for industrial applications. Most recent research topics on DSSC, for example, applications of nanostructured TiO2, ZnO electrodes, ionic liquid electrolytes, carbon nanotubes, graphene and solid state DSSC have all been included and discussed.

  6. Breast cancer stem cell-like cells are more sensitive to ionizing radiation than non-stem cells: role of ATM.

    Directory of Open Access Journals (Sweden)

    Seog-Young Kim

    Full Text Available There are contradictory observations about the different radiosensitivities of cancer stem cells and cancer non-stem cells. To resolve these contradictory observations, we studied radiosensitivities by employing breast cancer stem cell (CSC-like MDA-MB231 and MDA-MB453 cells as well as their corresponding non-stem cells. CSC-like cells proliferate without differentiating and have characteristics of tumor-initiating cells [1]. These cells were exposed to γ-rays (1.25-8.75 Gy and survival curves were determined by colony formation. A final slope, D(0, of the survival curve for each cell line was determined to measure radiosensitivity. The D(0 of CSC-like and non-stem MDA-MB-453 cells were 1.16 Gy and 1.55 Gy, respectively. Similar results were observed in MDA-MB-231 cells (0.94 Gy vs. 1.56 Gy. After determination of radiosensitivity, we investigated intrinsic cellular determinants which influence radiosensitivity including cell cycle distribution, free-radical scavengers and DNA repair. We observed that even though cell cycle status and antioxidant content may contribute to differential radiosensitivity, differential DNA repair capacity may be a greater determinant of radiosensitivity. Unlike non-stem cells, CSC-like cells have little/no sublethal damage repair, a low intracellular level of ataxia telangiectasia mutated (ATM and delay of γ-H2AX foci removal (DNA strand break repair. These results suggest that low DNA repair capacity is responsible for the high radiosensitivity of these CSC-like cells.

  7. Angiogenic and signalling proteins correlate with sensitivity to sequential treatment in renal cell cancer

    Science.gov (United States)

    Rosa, R; Damiano, V; Nappi, L; Formisano, L; Massari, F; Scarpa, A; Martignoni, G; Bianco, R; Tortora, G

    2013-01-01

    Background: We aimed to study key signalling proteins involved in angiogenesis and proliferation on the response to inhibitors of tyrosine kinases and mammalian target of rapamycin in first- and in second-line treatment of renal cell carcinoma (RCC). Methods: In a panel of human RCC tumours, in vitro and in nude mice, we evaluated the effect of sunitinib, sorafenib and everolimus, alone and in sequence, on tumour growth and expression of signalling proteins involved in proliferation and resistance to treatment. Results: We demonstrated that, as single agents, sunitinib, sorafenib and everolimus share similar activity in inhibiting cell proliferation, signal transduction and vascular endothelial growth factor (VEGF) secretion in different RCC models, both in vitro and in tumour xenografts. Pre-treatment with sunitinib reduced the response to subsequent sunitinib and sorafenib but not to everolimus. Inability by sunitinib to persistently inhibit HIF-1, VEGF and pMAPK anticipated treatment resistance in xenografted tumours. After first-line sunitinib, second-line treatment with everolimus was more effective than either sorafenib or rechallenge with sunitinib in interfering with signalling proteins, VEGF and interleukin-8, translating into a significant advantage in tumour growth inhibition and mice survival. Conclusion: We demonstrated that a panel of angiogenic and signalling proteins can correlate with the onset of resistance to sunitinib and the activity of everolimus in second line. PMID:23839492

  8. Amiloride sensitizes human pancreatic cancer cells to erlotinib in vitro through inhibition of the PI3K/AKT signaling pathway

    Science.gov (United States)

    Zheng, Yuan-ting; Yang, Hui-ying; Li, Tao; Zhao, Bei; Shao, Teng-fei; Xiang, Xiao-qiang; Cai, Wei-min

    2015-01-01

    Aim: Blockade of EGFR by EGFR tyrosine kinase inhibitors such as erlotinib is insufficient for effective treatment of human pancreatic cancer due to independent activation of the Akt pathway, while amiloride, a potassium-sparing diuretic, has been found as a potential Akt inhibitor. The aim of this study was to investigate the anticancer effects of combined amiloride with erlotinib against human pancreatic cancer cells in vitro. Methods: Cell proliferation, colony formation, cell cycle and apoptosis were analyzed in 4 human pancreatic cancer cell lines Bxpc-3, PANC-1, Aspc-1 and CFPAC-1 treated with erlotinib or amiloride alone, or in their combination. The synergistic analysis for the effects of combinations of amiloride and erlotinib was performed using Chou-Talalay's combination index isobolographic method. Results: Amiloride (10, 30, and 100 μmol/L) concentration-dependently potentiated erlotinib-induced inhibition of cell proliferation and colony formation in the 4 pancreatic cancer cell lines. Isobolographic analysis confirmed that combinations of amiloride and erlotinib produced synergistic cytotoxic effects. Amiloride significantly potentiated erlotinib-induced G0/G1 cell-cycle arrest and apoptosis in Bxpc-3 and PANC-1 cells. Amiloride inhibited EGF-stimulated phorsphorylation of AKT, and significantly enhanced erlotinib-induced downregulation of phorsphorylation of EGFR, AKT, PI3K P85 and GSK 3β in Bxpc-3 and PANC-1 cells. Conclusion: Amiloride sensitizes human pancreatic cancer cells to erlotinib in vitro through inhibition of the PI3K/AKT signaling pathway. Treatment of pancreatic cancer patients with combination of erlotinib and amiloride merits further investigation. PMID:25864651

  9. Knockdown of Ki-67 by dicer-substrate small interfering RNA sensitizes bladder cancer cells to curcumin-induced tumor inhibition.

    Directory of Open Access Journals (Sweden)

    Sivakamasundari Pichu

    Full Text Available Transitional cell carcinoma (TCC of the urinary bladder is the most common cancer of the urinary tract. Most of the TCC cases are of the superficial type and are treated with transurethral resection (TUR. However, the recurrence rate is high and the current treatments have the drawback of inducing strong systemic toxicity or cause painful cystitis. Therefore, it would be of therapeutic value to develop novel concepts and identify novel drugs for the treatment of bladder cancer. Ki-67 is a large nucleolar phosphoprotein whose expression is tightly linked to cell proliferation, and curcumin, a phytochemical derived from the rhizome Curcuma longa, has been shown to possess powerful anticancer properties. In this study, we evaluated the combined efficacy of curcumin and a siRNA against Ki-67 mRNA (Ki-67-7 in rat (AY-27 and human (T-24 bladder cancer cells. The anticancer effects were assessed by the determination of cell viability, apoptosis and cell cycle analysis. Ki-67-7 (10 nM and curcumin (10 µM, when treated independently, were moderately effective. However, in their combined presence, proliferation of bladder cancer cells was profoundly (>85% inhibited; the rate of apoptosis in the combined presence of curcumin and Ki-67-7 (36% was greater than that due to Ki-67-7 (14% or curcumin (13% alone. A similar synergy between curcumin and Ki-67-7 in inducing cell cycle arrest was also observed. Western blot analysis suggested that pretreatment with Ki-67-7 sensitized bladder cancer cells to curcumin-mediated apoptosis and cell cycle arrest by p53- and p21-independent mechanisms. These data suggest that a combination of anti-Ki-67 siRNA and curcumin could be a viable treatment against the proliferation of bladder cancer cells.

  10. Ginsenoside Rg3 sensitizes human non-small cell lung cancer cells to γ-radiation by targeting the nuclear factor-κB pathway.

    Science.gov (United States)

    Wang, Lei; Li, Xiankui; Song, Yi-Min; Wang, Bin; Zhang, Fu-Rui; Yang, Rui; Wang, Hua-Qi; Zhang, Guo-Jun

    2015-07-01

    At present, it is elusive how non-small cell lung cancer (NSCLC) develops resistance to γ-radiation; however, the transcription factor nuclear factor-κB (NF-κB) and NF-κB-regulated gene products have been proposed as mediators. Ginsenoside Rg3 is a steroidal saponin, which was isolated from Panax ginseng. Ginsenoside Rg3 possesses high pharmacological activity and has previously been shown to suppress NF-κB activation in various types of tumor cell. Therefore, the present study aimed to determine whether Rg3 could suppress NF-κB activation in NSCLC cells and sensitize NSCLC to γ-radiation, using an NSCLC cell line and NSCLC xenograft. A clone formation assay and lung tumor xenograft experiment were used to assess the radiosensitizing effects of ginsenoside Rg3. NF-κB/inhibitor of NF-κB (IκB) modulation was ascertained using an electrophoretic mobility shift assay and western blot analysis. NF-κB-regulated gene products were monitored by western blot analysis. The present study demonstrated that ginsenoside Rg3 was able to sensitize A549 and H1299 lung carcinoma cells to γ-radiation and significantly enhance the efficacy of radiation therapy in C57BL/6 mice bearing a Lewis lung carcinoma cell xenograft tumor. Furthermore, ginsenoside Rg3 suppressed NF-κB activation, phosphorylation of IκB protein and expression of NF-κB-regulated gene products (cyclin D1, c-myc, B-cell lymphoma 2, cyclooxygenase-2, matrix metalloproteinase-9 and vascular endothelial growth factor), a number of which were induced by radiation therapy and mediate radioresistance. In conclusion, the results of the present study suggested that ginsenoside Rg3 may potentiate the antitumor effects of radiation therapy in NSCLC by suppressing NF-κB activity and NF-κB-regulated gene products, leading to the inhibition of tumor progression.

  11. Metabolomic Profiling of the Effects of Melittin on Cisplatin Resistant and Cisplatin Sensitive Ovarian Cancer Cells Using Mass Spectrometry and Biolog Microarray Technology

    Directory of Open Access Journals (Sweden)

    Sanad Alonezi

    2016-10-01

    Full Text Available In the present study, liquid chromatography-mass spectrometry (LC-MS was employed to characterise the metabolic profiles of two human ovarian cancer cell lines A2780 (cisplatin-sensitive and A2780CR (cisplatin-resistant in response to their exposure to melittin, a cytotoxic peptide from bee venom. In addition, the metabolomics data were supported by application of Biolog microarray technology to examine the utilisation of carbon sources by the two cell lines. Data extraction with MZmine 2.14 and database searching were applied to provide metabolite lists. Principal component analysis (PCA gave clear separation between the cisplatin-sensitive and resistant strains and their respective controls. The cisplatin-resistant cells were slightly more sensitive to melittin than the sensitive cells with IC50 values of 4.5 and 6.8 μg/mL respectively, although the latter cell line exhibited the greatest metabolic perturbation upon treatment. The changes induced by melittin in the cisplatin-sensitive cells led mostly to reduced levels of amino acids in the proline/glutamine/arginine pathway, as well as to decreased levels of carnitines, polyamines, adenosine triphosphate (ATP and nicotinamide adenine dinucleotide (NAD+. The effects on energy metabolism were supported by the data from the Biolog assays. The lipid compositions of the two cell lines were quite different with the A2780 cells having higher levels of several ether lipids than the A2780CR cells. Melittin also had some effect on the lipid composition of the cells. Overall, this study suggests that melittin might have some potential as an adjuvant therapy in cancer treatment.

  12. Id4 Promotes Senescence and Sensitivity to Doxorubicin-induced Apoptosis in DU145 Prostate Cancer Cells

    OpenAIRE

    Carey, Jason P; Knowell, Ashley Evans; Chinaranagari, Swathi; Chaudhary, Jaideep

    2013-01-01

    Inhibitor of differentiation proteins (Id1, 2, 3 and 4) are dominant negative regulators of basic helix loop helix transcription factors and play dominant roles in cancer cells, spanning several molecular pathways including senescence, invasion, metastasis, proliferation and apoptosis. In contrast to high Id1, Id2 and Id3 expression, the expression of Id4 is epigenetically silenced in prostate cancer. In the present study we demonstrated a novel role of Id4, that of promotion of cellular sene...

  13. Highly sensitive proximity mediated immunoassay reveals HER2 status conversion in the circulating tumor cells of metastatic breast cancer patients

    Directory of Open Access Journals (Sweden)

    Kim Phillip

    2011-12-01

    Full Text Available Abstract Background The clinical benefits associated with targeted oncology agents are generally limited to subsets of patients. Even with favorable biomarker profiles, many patients do not respond or acquire resistance. Existing technologies are ineffective for treatment monitoring as they provide only static and limited information and require substantial amounts of tissue. Therefore, there is an urgent need to develop methods that can profile potential therapeutic targets with limited clinical specimens during the course of treatment. Methods We have developed a novel proteomics-based assay, Collaborative Enzyme Enhanced Reactive-immunoassay (CEER that can be used for analyzing clinical samples. CEER utilizes the formation of unique immuno-complex between capture-antibodies and two additional detector-Abs on a microarray surface. One of the detector-Abs is conjugated to glucose oxidase (GO, and the other is conjugated to Horse Radish Peroxidase (HRP. Target detection requires the presence of both detector-Abs because the enzyme channeling event between GO and HRP will not occur unless both Abs are in close proximity. Results CEER was able to detect single-cell level expression and phosphorylation of human epidermal growth factor receptor 2 (HER2 and human epidermal growth factor receptor 1 (HER1 in breast cancer (BCa systems. The shift in phosphorylation profiles of receptor tyrosine kinases (RTKs and other signal transduction proteins upon differential ligand stimulation further demonstrated extreme assay specificity in a multiplexed array format. HER2 analysis by CEER in 227 BCa tissues showed superior accuracy when compared to the outcome from immunohistochemistry (IHC (83% vs. 96%. A significant incidence of HER2 status alteration with recurrent disease was observed via circulating tumor cell (CTC analysis, suggesting an evolving and dynamic disease progression. HER2-positive CTCs were found in 41% (7/17 while CTCs with significant HER2

  14. Cytotoxicity of 5-fluorouracil-loaded pH-sensitive liposomal nanoparticles in colorectal cancer cell lines

    OpenAIRE

    Udofot, Ofonime; Affram, Kevin; Israel, Bridg'ette; Agyare, Edward

    2015-01-01

    5-Fluorouracil (5-FU) is widely used in cancer therapy, either alone or in combination with other anti-cancer drugs. However, poor membrane permeability and a short half-life (5-20 min) due to rapid metabolism in the body necessitate the continuous administration of high doses of 5-FU to maintain the minimum therapeutic serum concentration. This is associated with significant side effects and a possibility of severe toxic effects. This study aimed to formulate 5-FU-loaded pH-sensitive liposom...

  15. Inhibition of human 67-kDa laminin receptor sensitizes multidrug resistance colon cancer cell line SW480 for apoptosis induction.

    Science.gov (United States)

    Lu, Chun-Lei; Xu, Jian; Yao, Hao-Jie; Luo, Kun-Lun; Li, Jie-Ming; Wu, Tao; Wu, Guo-Zhong

    2016-01-01

    The adhesion mediated drug resistance in cancer cells resulted from adhesion of the extracellular matrix is a major cause for multidrug resistance (MDR) and leads chemotherapeutic failure for colon cancer. In this study, we explored the role of 67-kDa laminin receptor (67LR) in chemotherapeutic drug resistance in colon cancer cells. SiRNA-mediated knockdown of 67LR decreased the cell adhesion when laminins were applied. Moreover, 67LR knockdown increased the expression of pro-apoptotic gene Bax but inhibited the expression of anti-apoptotic gene Bcl-2. Enhanced apoptosis was observed in 67LR siRNA-transfected SW480 cell when the cell was treated with doxorubicin for apoptosis induction. Furthermore, MTT assay revealed that the IC50 of chemotherapeutic toward SW480 cell adhesion to laminins was reduced after 67LR knockdown, indicating there was a significant increase of drug sensitivity in SW480 cell. In conclusion, our study demonstrated that 67LR plays a considerable role in the development of colon cancer MDR.

  16. Disturbance of DKK1 level is partly involved in survival of lung cancer cells via regulation of ROMO1 and γ-radiation sensitivity

    Energy Technology Data Exchange (ETDEWEB)

    Kim, In Gyu, E-mail: igkim@kaeri.re.kr [Department of Radiation Biology, Environmental Radiation Research Group, Korea Atomic Energy Research Institute, P.O. Box 105, Yuseong, Daejeon 305-600 (Korea, Republic of); Department of Radiation Biotechnology and Applied Radioisotope, University of Science and Technology (UST), 989-111 Daedeok-daero, Yuseong-gu, Daejeon 305-353 (Korea, Republic of); Kim, Seo Yoen [Department of Radiation Biology, Environmental Radiation Research Group, Korea Atomic Energy Research Institute, P.O. Box 105, Yuseong, Daejeon 305-600 (Korea, Republic of); Biomedical Translational Research Center, Korea Research Institute of Bioscience and Biotechnology, 125 Gwahak-ro, Yuseong-gu, Daejeon 305-806 (Korea, Republic of); Kim, Hyun A; Kim, Jeong Yul [Department of Radiation Biology, Environmental Radiation Research Group, Korea Atomic Energy Research Institute, P.O. Box 105, Yuseong, Daejeon 305-600 (Korea, Republic of); Lee, Jae Ha; Choi, Soo Im [Department of Radiation Biology, Environmental Radiation Research Group, Korea Atomic Energy Research Institute, P.O. Box 105, Yuseong, Daejeon 305-600 (Korea, Republic of); Department of Radiation Biotechnology and Applied Radioisotope, University of Science and Technology (UST), 989-111 Daedeok-daero, Yuseong-gu, Daejeon 305-353 (Korea, Republic of); Han, Jeong Ran; Kim, Kug Chan [Department of Radiation Biology, Environmental Radiation Research Group, Korea Atomic Energy Research Institute, P.O. Box 105, Yuseong, Daejeon 305-600 (Korea, Republic of); Cho, Eun Wie [Biomedical Translational Research Center, Korea Research Institute of Bioscience and Biotechnology, 125 Gwahak-ro, Yuseong-gu, Daejeon 305-806 (Korea, Republic of)

    2014-01-03

    Highlights: •DKK1 was expressed differently among non-small-cell lung cancer cell lines. •DKK1 negatively regulated ROMO1 gene expression. •Disturbance of DKK1 level induced the imbalance of cellular ROS. •DKK1/ROMO1-induced ROS imbalance is involved in cell survival in NSCLC. -- Abstract: Dickkopf1 (DKK1), a secreted protein involved in embryonic development, is a potent inhibitor of the Wnt signaling pathway and has been postulated to be a tumor suppressor or tumor promoter depending on the tumor type. In this study, we showed that DKK1 was expressed differently among non-small-cell lung cancer cell lines. The DKK1 expression level was much higher in A549 cells than in H460 cells. We revealed that blockage of DKK1 expression by silencing RNA in A549 cells caused up-regulation of intracellular reactive oxygen species (ROS) modulator (ROMO1) protein, followed by partial cell death, cell growth inhibition, and loss of epithelial–mesenchymal transition property caused by ROS, and it also increased γ-radiation sensitivity. DKK1 overexpression in H460 significantly inhibited cell survival with the decrease of ROMO1 level, which induced the decrease of cellular ROS. Thereafter, exogenous N-acetylcysteine, an antioxidant, or hydrogen peroxide, a pro-oxidant, partially rescued cells from death and growth inhibition. In each cell line, both overexpression and blockage of DKK1 not only elevated p-RB activation, which led to cell growth arrest, but also inactivated AKT/NF-kB, which increased radiation sensitivity and inhibited cell growth. This study is the first to demonstrate that strict modulation of DKK1 expression in different cell types partially maintains cell survival via tight regulation of the ROS-producing ROMO1 and radiation resistance.

  17. Sensitization of multidrug-resistant human cancer cells to Hsp90 inhibitors by down-regulation of SIRT1.

    Science.gov (United States)

    Kim, Hak-Bong; Lee, Su-Hoon; Um, Jee-Hyun; Oh, Won Keun; Kim, Dong-Wan; Kang, Chi-Dug; Kim, Sun-Hee

    2015-11-03

    The effectiveness of Hsp90 inhibitors as anticancer agents was limited in multidrug-resistant (MDR) human cancer cells due to induction of heat shock proteins (Hsps) such as Hsp70/Hsp27 and P-glycoprotein (P-gp)-mediated efflux. In the present study, we showed that resistance to Hsp90 inhibitors of MDR human cancer cells could be overcome with SIRT1 inhibition. SIRT1 knock-down or SIRT1 inhibitors (amurensin G and EX527) effectively suppressed the resistance to Hsp90 inhibitors (17-AAG and AUY922) in several MDR variants of human lymphoblastic leukemia and human breast cancer cell lines. SIRT1 inhibition down-regulated the expression of heat shock factor 1 (HSF1) and subsequently Hsps and facilitated Hsp90 multichaperone complex disruption via hyperacetylation of Hsp90/Hsp70. These findings were followed by acceleration of ubiquitin ligase CHIP-mediated mutant p53 (mut p53) degradation and subsequent down-regulation of P-gp in 17-AAG-treated MDR cancer cells expressing P-gp and mut p53 after inhibition of SIRT1. Therefore, combined treatment with Hsp90 inhibitor and SIRT1 inhibitor could be a more effective therapeutic approach for Hsp90 inhibitor-resistant MDR cells via down-regulation of HSF1/Hsps, mut p53 and P-gp.

  18. The anti-obesity drug orlistat promotes sensitivity to TRAIL by two different pathways in hormone-refractory prostate cancer cells.

    Science.gov (United States)

    Fujiwara, Jun; Sowa, Yoshihiro; Horinaka, Mano; Koyama, Makoto; Wakada, Miki; Miki, Tsuneharu; Sakai, Toshiyuki

    2012-05-01

    The administration of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is one of the expected cancer therapeutics. However, improvements are required in therapies against TRAIL-resistant tumor cells. We report, here, that the anti-obesity drug orlistat enhances the sensitivity to TRAIL in hormone-refractory prostate cancer (HRPC) cells through two different pathways. The combination of orlistat and TRAIL remarkably induced apoptosis in TRAIL-resistant HRPC, DU145 and PC3 cells. Orlistat induced the expression of death receptor (DR) 5, which is one of the TRAIL receptors, at both the mRNA and protein levels. The suppression of DR5 with siRNA reduced the apoptosis induced by the combination of orlistat and TRAIL, suggesting that the apoptosis was at least partially due to the upregulation of DR5. Although the upregulation by orlistat of CHOP at both mRNA and protein levels was observed in both cell lines, the activation of the DR5 promoter in DU145 cells was CHOP-dependent, but that in PC3 cells was CHOP-independent. Moreover, orlistat induced reactive oxygen species (ROS), and a ROS scavenger diminished the sensitivity to TRAIL through the suppression of CHOP and DR5 expression in both cell lines. These results suggest that there are two pathways of upregulation of DR5 by orlistat, which are the ROS-CHOP pathway and the ROS-direct pathway. In conclusion, orlistat promotes the sensitivity to TRAIL by ROS-mediated pathways in prostate cancer cells, especially in TRAIL-resistant cells. We believe that the combination of orlistat and TRAIL in HRPC is promising as a new chemotherapeutic strategy.

  19. Sensitization of cancer cells to radiation by selenadiazole derivatives by regulation of ROS-mediated DNA damage and ERK and AKT pathways

    Energy Technology Data Exchange (ETDEWEB)

    Xie, Qiang [Department of Chemistry, Jinan University, Guangzhou 510632 (China); Wu Jing Zong Dui Hospital of Guangdong Province, Guangzhou (China); Zhou, Yangliang; Lan, Guoqiang; Yang, Liye; Zheng, Wenjie; Liang, Yuanwei [Department of Chemistry, Jinan University, Guangzhou 510632 (China); Chen, Tianfeng, E-mail: tchentf@jnu.edu.cn [Department of Chemistry, Jinan University, Guangzhou 510632 (China)

    2014-06-20

    Highlights: • Selenadiazole derivatives could be used as an effective and low toxic sensitizer for radiotherapy. • Selenadiazole derivatives enhances radiation-induced growth inhibition on A375 cells through induction of G2/M arrest. • ROS-mediated signaling pathways play important roles in radiosensitization of selenadiazole derivatives. - Abstract: X-ray-based radiotherapy represents one of the most effective ways in treating human cancers. However, radioresistance and side effect remain as the most challenging issue. This study describes the design and application of novel selenadiazole derivatives as radiotherapy sensitizers to enhance X-ray-induced inhibitory effects on A375 human melanoma and Hela human cervical carcinoma cells. The results showed that, pretreatment of the cells with selenadiazole derivatives dramatically enhance X-ray-induced growth inhibition and colony formation. Flow cytometry analysis indicates that the sensitization by selenadiazole derivatives was mainly caused by induction of G2/M cell cycle arrest. Results of Western blotting demonstrated that the combined treatment-induced A375 cells growth inhibition was achieved by triggering reactive oxygen species-mediated DNA damage involving inactivation of AKT and MAPKs. Further investigation revealed that selenadiazole derivative in combination with X-ray could synergistically inhibit the activity of thioredoxin reductase-1 in A375 cells. Taken together, these results suggest that selenadiazole derivatives can act as novel radiosensitizer with potential application in combating human cancers.

  20. Enhanced sensitivity to mitomycin C by abating heat shock protein 70 expression in human bladder cancer cell line of BIU-87

    Institute of Scientific and Technical Information of China (English)

    HE Ling-feng; GUAN Kao-peng; YAN Zheng; YE Hai-yun; XU Ke-xin; REN Liang; HOU Shu-kun

    2005-01-01

    Background Bladder cancer is a relatively common tumor in the urinary system, in which mitomycin C (MMC)-based chemotherapy or combination chemotherapy has been mainly used to treat patients with advanced bladder cancer. The prognosis of patients with advanced bladder cancer is still extremely poor in spite of recent therapeutic advances. To improve the prognosis, the sensitivity of tumor cells to mitomycin C by the induction of apoptosis with the abating heat shock protein 70 (HSP70) expression in human bladder cancer cell lines of BIU-87 was investigated. Methods HSP70 expression was abated in BIU-87 cells by HSP mRNA antisense oligomers. MTT assay and the clone-forming test were used for evaluating the sensitivity of cells to MMC. Apoptosis was assessed using both fluorescent microscopy after staining the cells with Hoechst 33258 and DNA fragment ladder agarose electrophoresis. Thirty-two male six-week-old BALB/c nude mice, at the beginning of the experiment, were used to evaluate the effect of antisense oligomers (ASO) on the tumor formation in vivo. Results HSP70 expression in BIU-87 was effectively abated by HSP70 mRNA antisense oligomers. The percentage of apoptotic cells in ASO group was greater than in sense oligomers (SO) [P50%) was more than that of ASO or MMC group alone (all P<0.05). Conclusions The abating level of HSP70 expression can strengthen the sensitivity of BIU-87 to MMC. One of this effect might be related to the induction of apoptosis by abating HSP70 expression.

  1. TIMP-1 overexpression does not affect sensitivity to HER2-targeting drugs in the HER2-gene-amplified SK-BR-3 human breast cancer cell line.

    Science.gov (United States)

    Deng, Xiaohong; Fogh, Louise; Lademann, Ulrik; Jensen, Vibeke; Stenvang, Jan; Yang, Huanming; Brünner, Nils; Schrohl, Anne-Sofie

    2013-04-01

    Tissue inhibitor of metalloproteinases-1 (TIMP-1) has been suggested as a marker of prognosis and response to treatment in breast cancer. In vitro, TIMP-1 can regulate shedding of the extracellular domain of HER2 and signalling via the Akt pathway, and we hypothesize that TIMP-1 therefore can affect sensitivity to the HER2-targeting drugs trastuzumab and lapatinib. SK-BR-3 human breast cancer cells were stably transfected with TIMP-1, characterized with regard to TIMP-1 protein expression, proliferation, and functionality of the secreted TIMP-1, and the sensitivity to trastuzumab and lapatinib was studied in five selected single-cell subclones expressing TIMP-1 protein at various levels plus the parental SK-BR-3 cell line. Both trastuzumab and lapatinib reduced cell viability, as determined by MTT assay, but the sensitivity to the drugs was not associated with the expression level of TIMP-1 protein. Western blotting showed that the activation of Akt, PTEN, and HER2 as well as ADAM10 was similar in all clones. In conclusion, in this model, TIMP-1 overexpression does not affect HER2 cleavage by ADAM10 or signalling via the Akt pathway, and TIMP-1 does not influence sensitivity to trastuzumab and lapatinib.

  2. Squamous cell skin cancer

    Science.gov (United States)

    ... that reflect light more, such as water, sand, concrete, and areas that are painted white. The higher ... - skin - squamous cell; Skin cancer - squamous cell; Nonmelanoma skin cancer - squamous ...

  3. Role of the Chemokine MCP-1 in Sensitization of PKC-Medicated Apoptosis in Prostate Cancer Cells

    Science.gov (United States)

    2008-02-01

    prostate cancer cells. Lack of proteolytic cleavage of PKCδ. J. Biol. Chem. 275: 7574-7582 (2000). 5. Garcia -Bermejo, M.L., Leskow, F.C., Fujii, T., Wang...Q., Blumberg, P.M., Ohba, M., Kuroki, T., 5 Han, K.C., Lee, J., Marquez , V.E., and Kazanietz, M.G. Diacylglycerol (DAG)-lactones, a new class of

  4. Mitotic slippage and expression of survivin are linked to differential sensitivity of human cancer cell-lines to the Kinesin-5 inhibitor monastrol.

    Directory of Open Access Journals (Sweden)

    Hila Asraf

    Full Text Available The mitotic Kinesin-5 motor proteins crosslink and slide apart antiparallel spindle microtubules, thus performing essential functions in mitotic spindle dynamics. Specific inhibition of their function by monastrol-like small molecules has been examined in clinical trials as anticancer treatment, with only partial success. Thus, strategies that improve the efficiency of monastrol-like anticancer drugs are required. In the current study, we examined the link between sensitivity to monastrol and occurrence of mitotic slippage in several human cell-lines. We found that the rank of sensitivity to monastrol, from most sensitive to least sensitive, is: AGS > HepG2 > Lovo > Du145 ≥ HT29. We show correlation between the sensitivity of a particular cell-line to monastrol and the tendency of the same cell-line to undergo mitotic slippage. We also found that in the monastrol resistant HT29 cells, prolonged monastrol treatments increase mRNA and protein levels of the chromosomal passenger protein survivin. In contrast, survivin levels are not increased by this treatment in the monastrol-sensitive AGS cells. We further show that over-expression of survivin in the monastrol-sensitive AGS cells reduces mitotic slippage and increases resistance to monastrol. Finally, we show that during short exposure to monastrol, Si RNA silencing of survivin expression reduces cell viability in both AGS and HT29 cells. Our data suggest that the efficiency of anti-cancer treatment with specific kinesin-5 inhibitors may be improved by modulation of expression levels of survivin.

  5. The BRAF{sup T1799A} mutation confers sensitivity of thyroid cancer cells to the BRAF{sup V600E} inhibitor PLX4032 (RG7204)

    Energy Technology Data Exchange (ETDEWEB)

    Xing, Joanna [Division of Head and Neck Cancer Research, Department of Otolaryngology and Head and Neck Surgery, The Johns Hopkins University School of Medicine, Baltimore, MD 21231 (United States); Liu, Ruixin; Xing, Mingzhao [Laboratory for Cellular and Molecular Thyroid Research, Division of Endocrinology and Metabolism, The Johns Hopkins University School of Medicine, Baltimore, MD 21287 (United States); Trink, Barry, E-mail: btrink@jhmi.edu [Division of Head and Neck Cancer Research, Department of Otolaryngology and Head and Neck Surgery, The Johns Hopkins University School of Medicine, Baltimore, MD 21231 (United States)

    2011-01-28

    Research highlights: {yields} Exciting therapeutic potential has been recently reported for the BRAF{sup V600E} inhibitor PLX4032 in melanoma. {yields} We tested the effects of PLX4032 on the growth of thyroid cancer cells which often harbor the BRAF{sup V600E} mutation. {yields} We observed a potent BRAF{sup V600E}-dependent inhibition of thyroid cancer cells by PLX4032. {yields} We thus demonstrated an important therapeutic potential of PLX4032 for thyroid cancer. -- Abstract: Aberrant signaling of the Ras-Raf-MEK-ERK (MAP kinase) pathway driven by the mutant kinase BRAF{sup V600E}, as a result of the BRAF{sup T1799A} mutation, plays a fundamental role in thyroid tumorigenesis. This study investigated the therapeutic potential of a BRAF{sup V600E}-selective inhibitor, PLX4032 (RG7204), for thyroid cancer by examining its effects on the MAP kinase signaling and proliferation of 10 thyroid cancer cell lines with wild-type BRAF or BRAF{sup T1799A} mutation. We found that PLX4032 could effectively inhibit the MAP kinase signaling, as reflected by the suppression of ERK phosphorylation, in cells harboring the BRAF{sup T1799A} mutation. PLX4032 also showed a potent and BRAF mutation-selective inhibition of cell proliferation in a concentration-dependent manner. PLX4032 displayed low IC{sub 50} values (0.115-1.156 {mu}M) in BRAF{sup V600E} mutant cells, in contrast with wild-type BRAF cells that showed resistance to the inhibitor with high IC{sub 50} values (56.674-1349.788 {mu}M). Interestingly, cells with Ras mutations were also sensitive to PLX4032, albeit moderately. Thus, this study has confirmed that the BRAF{sup T1799A} mutation confers cancer cells sensitivity to PLX4032 and demonstrated its specific potential as an effective and BRAF{sup T1799A} mutation-selective therapeutic agent for thyroid cancer.

  6. Improvement of gemcitabine sensitivity of p53-mutated pancreatic cancer MiaPaCa-2 cells by RUNX2 depletion-mediated augmentation of TAp73-dependent cell death

    Science.gov (United States)

    Nakamura, M; Sugimoto, H; Ogata, T; Hiraoka, K; Yoda, H; Sang, M; Sang, M; Zhu, Y; Yu, M; Shimozato, O; Ozaki, T

    2016-01-01

    Pancreatic cancer exhibits the worst prognostic outcome among human cancers. Recently, we have described that depletion of RUNX2 enhances gemcitabine (GEM) sensitivity of p53-deficient pancreatic cancer AsPC-1 cells through the activation of TAp63-mediated cell death pathway. These findings raised a question whether RUNX2 silencing could also improve GEM efficacy on pancreatic cancer cells bearing p53 mutation. In the present study, we have extended our study to p53-mutated pancreatic cancer MiaPaCa-2 cells. Based on our current results, MiaPaCa-2 cells were much more resistant to GEM as compared with p53-proficient pancreatic cancer SW1990 cells, and there existed a clear inverse relationship between the expression levels of TAp73 and RUNX2 in response to GEM. Forced expression of TAp73α in MiaPaCa-2 cells significantly promoted cell cycle arrest and/or cell death, indicating that a large amount of TAp73 might induce cell death even in the presence of mutant p53. Consistent with this notion, overexpression of TAp73α stimulated luciferase activity driven by p53/TAp73-target gene promoters in MiaPaCa-2 cells. Similar to AsPC-1 cells, small interfering RNA-mediated knockdown of RUNX2 remarkably enhanced GEM sensitivity of MiPaCa-2 cells. Under our experimental conditions, TAp73 further accumulated in RUNX2-depleted MiaPaCa-2 cells exposed to GEM relative to GEM-treated non-silencing control cells. As expected, silencing of p73 reduced GEM sensitivity of MiPaCa-2 cells. Moreover, GEM-mediated Tyr phosphorylation level of TAp73 was much more elevated in RUNX2-depleted MiaPaCa-2 cells. Collectively, our present findings strongly suggest that knockdown of RUNX2 contributes to a prominent enhancement of GEM sensitivity of p53-mutated pancreatic cancer cells through the activation of TAp73-mediated cell death pathway, and also provides a promising strategy for the treatment of patients with pancreatic cancer bearing p53 mutation. PMID:27294865

  7. Histone deacetylase inhibitors sensitize lung cancer cells to hyperthermia: involvement of Ku70/SirT-1 in thermo-protection.

    Science.gov (United States)

    Hassan, Mohamed K; Watari, Hidemichi; Salah-Eldin, Alaa-Eldin; Sultan, Ahmed S; Mohamed, Zainab; Fujioka, Yoichiro; Ohba, Yusuke; Sakuragi, Noriaki

    2014-01-01

    This study describes the sensitization mechanism to thermal stress by histone deacetylase inhibitors (HDACIs) in lung cancer cells and shows that Ku70, based on its acetylation status, mediates the protection of lung cancer from hyperthermia (42.5°C, 1-6 hrs). Ku70 regulates apoptosis by sequestering pro-apoptotic Bax. However, its role in thermal stress is not fully understood. The findings showed that, pre-treating lung cancer cells with HDACIs, nicotinamide (NM) or Trichostatin A (TsA) or both significantly enhanced hyperthermia-induced Bax-dependent apoptosis in PC-10 cells. We found that hyperthermia induces SirT-1, Sirtuin, upregulation but not HDAC6 or SirT-3, therefore transfection with dominant negative SirT-1 (Y/H) also eliminated the protection and resulted in more cell death by hyperthermia, in H1299 cells through Bax activation. Hyperthermia alone primed lung cancer cells to apoptosis without prominent death. After hyperthermia Bax was upregulated, Bcl-2 was downregulated, the Bax/Bcl-2 ratio was inversed and Bax/Bcl-2 heterodimer was dissociated. Although hyperthermia did not affect total Ku70 expression level, it stimulated Ku70 deacetylation, which in turn could bind more Bax in the PC-10 cells. These findings suggest an escape mechanism from hyperthermia-induced Bax activation. To verify the role of Ku70 in this protection mechanism, Ku70 was silenced by siRNA. Ku70 silencing significantly sensitized the lung cancer cells to hyperthermia. The Ku70 KD cells underwent cytotoxic G1 arrest and caspase-dependant apoptosis when compared to scrambled transfectants which showed only G2/M cytostatic arrest in the cell lines investigated, suggesting an additional cell cycle-dependent, novel, role of Ku70 in protection from hyperthermia. Taken together, our data show a Ku70-dependent protection mechanism from hyperthermia. Targeting Ku70 and/or its acetylation during hyperthermia may represent a promising therapeutic approach for lung cancer.

  8. Histone deacetylase inhibitors sensitize lung cancer cells to hyperthermia: involvement of Ku70/SirT-1 in thermo-protection.

    Directory of Open Access Journals (Sweden)

    Mohamed K Hassan

    Full Text Available This study describes the sensitization mechanism to thermal stress by histone deacetylase inhibitors (HDACIs in lung cancer cells and shows that Ku70, based on its acetylation status, mediates the protection of lung cancer from hyperthermia (42.5°C, 1-6 hrs. Ku70 regulates apoptosis by sequestering pro-apoptotic Bax. However, its role in thermal stress is not fully understood. The findings showed that, pre-treating lung cancer cells with HDACIs, nicotinamide (NM or Trichostatin A (TsA or both significantly enhanced hyperthermia-induced Bax-dependent apoptosis in PC-10 cells. We found that hyperthermia induces SirT-1, Sirtuin, upregulation but not HDAC6 or SirT-3, therefore transfection with dominant negative SirT-1 (Y/H also eliminated the protection and resulted in more cell death by hyperthermia, in H1299 cells through Bax activation. Hyperthermia alone primed lung cancer cells to apoptosis without prominent death. After hyperthermia Bax was upregulated, Bcl-2 was downregulated, the Bax/Bcl-2 ratio was inversed and Bax/Bcl-2 heterodimer was dissociated. Although hyperthermia did not affect total Ku70 expression level, it stimulated Ku70 deacetylation, which in turn could bind more Bax in the PC-10 cells. These findings suggest an escape mechanism from hyperthermia-induced Bax activation. To verify the role of Ku70 in this protection mechanism, Ku70 was silenced by siRNA. Ku70 silencing significantly sensitized the lung cancer cells to hyperthermia. The Ku70 KD cells underwent cytotoxic G1 arrest and caspase-dependant apoptosis when compared to scrambled transfectants which showed only G2/M cytostatic arrest in the cell lines investigated, suggesting an additional cell cycle-dependent, novel, role of Ku70 in protection from hyperthermia. Taken together, our data show a Ku70-dependent protection mechanism from hyperthermia. Targeting Ku70 and/or its acetylation during hyperthermia may represent a promising therapeutic approach for lung cancer.

  9. hMena+11a Isoform Serves as a Marker of Epithelial Phenotype and Sensitivity to EGFR Inhibition in Human Pancreatic Cancer Cell Lines

    Science.gov (United States)

    Pino, Maria S.; Balsamo, Michele; Di Modugno, Francesca; Mottolese, Marcella; Alessio, Massimo; Melucci, Elisa; Milella, Michele; McConkey, David J.; Philippar, Ulrike; Gertler, Frank B.; Natali, Pier Giorgio; Nistico, Paola

    2008-01-01

    Purpose hMena, member of the Ena/VASP protein family, is a cytoskeletal protein that is involved in the regulation of cell motility and adhesion. The aim of this study was to determine whether or not the expression of hMena isoforms correlated with sensitivity to EGFR tyrosine kinase inhibitors and could serve as markers with potential clinical use. Experimental design Human pancreatic ductal adenocarcinoma (PDAC) cell lines were characterized for in vitro sensitivity to erlotinib, expression of HER family receptors, markers of epithelial to mesenchymal transition (EMT), and expression of hMena and its isoform hMena+11a. The effects of EGF and erlotinib on hMena expression as well as the effect of hMena knock-down on cell proliferation were also evaluated. Results hMena was detected in all of the pancreatic tumor cell lines tested as well as in the majority of the human tumor samples [primary (92%) and metastatic (86%)]. Intriguingly, in vitro hMena+11a isoform was specifically associated with an epithelial phenotype, EGFR dependency and sensitivity to erlotinib. In epithelial BxPC3 cells EGF upregulated hMena/hMena+11a and erlotinib downregulated expression. hMena knock-down reduced cell proliferation and MAPK and AKT activation in BxPC3 cells and promoted the growth inhibitory effects of erlotinib. Conclusions Collectively, our data indicate that the hMena+11a isoform is associated with an epithelial phenotype and identifies EGFR dependent cell lines that are sensitive to the EGFR inhibitor erlotinib. The availability of anti-hMena+11a specific probes may offer a new tool in pancreatic cancer management if these results can be verified prospectively in cancer patients. PMID:18676769

  10. SMARCA4-inactivating mutations increase sensitivity to Aurora kinase A inhibitor VX-680 in non-small cell lung cancers

    Science.gov (United States)

    Tagal, Vural; Wei, Shuguang; Zhang, Wei; Brekken, Rolf A.; Posner, Bruce A.; Peyton, Michael; Girard, Luc; Hwang, TaeHyun; Wheeler, David A.; Minna, John D.; White, Michael A.; Gazdar, Adi F.; Roth, Michael G.

    2017-01-01

    Mutations in the SMARCA4/BRG1 gene resulting in complete loss of its protein (BRG1) occur frequently in non-small cell lung cancer (NSCLC) cells. Currently, no single therapeutic agent has been identified as synthetically lethal with SMARCA4/BRG1 loss. We identify AURKA activity as essential in NSCLC cells lacking SMARCA4/BRG1. In these cells, RNAi-mediated depletion or chemical inhibition of AURKA induces apoptosis and cell death in vitro and in xenograft mouse models. Disc large homologue-associated protein 5 (HURP/DLGAP5), required for AURKA-dependent, centrosome-independent mitotic spindle assembly is essential for the survival and proliferation of SMARCA4/BRG1 mutant but not of SMARCA4/BRG1 wild-type cells. AURKA inhibitors may provide a therapeutic strategy for biomarker-driven clinical studies to treat the NSCLCs harbouring SMARCA4/BRG1-inactivating mutations. PMID:28102363

  11. Inhibition of AKT with the orally active allosteric AKT inhibitor, MK-2206, sensitizes endometrial cancer cells to progestin.

    Directory of Open Access Journals (Sweden)

    Alok Pant

    Full Text Available Progestin resistance is a major obstacle to treating early stage, well-differentiated endometrial cancer as well as recurrent endometrial cancer. The mechanism behind the suboptimal response to progestin is not well understood. The PTEN tumor suppressor gene is frequently mutated in type I endometrial cancers and this mutation results in hyperactivation of the PI3K/AKT pathway. We hypothesized that increased activation of AKT promotes an inadequate response to progestins in endometrial cancer cells. Ishikawa cells stably transfected with progesterone receptor B (PRB23 cells were treated with the AKT inhibitor, MK-2206, which effectively decreased levels of p(Ser473-AKT in a dose-dependent (10 nM to 1 uM and time-dependent manner (0.5 h to 24 h. MK-2206 inhibited levels of p(Thr308-AKT and a downstream target, p(Thr246-PRAS40, but did not change levels of p(Thr202/Tyr204ERK or p(Thr13/Tyr185SAPK/JNK, demonstrating specificity of MK-2206 for AKT. Additionally, MK-2206 treatment of PRB23 cells resulted in a significant increase in levels of progesterone receptor B (PRB protein. Microarray analysis of PRB23 cells identified PDK4 as the most highly upregulated gene among 70 upregulated genes in response to R5020. Inhibition of AKT further upregulated progestin-mediated expression of PDK4 but did not affect another progestin-responsive gene, SGK1. Treatment of PRB23 cells with R5020 and MK-2206 independently decreased viability of cells while the combination of R5020 and MK-2206 caused the greatest decrease in cell viability. Furthermore, mice with xenografted tumors treated with MK-2206 alone or with progesterone alone exhibited modest reductions in their tumor volume. The largest decrease in tumor size was observed in the mice treated with both MK-2206 and progesterone; these tumors exhibited the least proliferation (Ki67 and the most apoptosis (cleaved caspase-3 of all the treatment groups. In summary, inhibition of AKT stabilizes the Progesterone

  12. 4-IBP, a σ1 Receptor Agonist, Decreases the Migration of Human Cancer Cells, Including Glioblastoma Cells, In Vitro and Sensitizes Them In Vitro and In Vivo to Cytotoxic Insults of Proapoptotic and Proautophagic Drugs

    Directory of Open Access Journals (Sweden)

    Veronique Mégalizzi

    2007-05-01

    Full Text Available Although the molecular function of cr receptors has not been fully defined and the natural ligand(s is still not known, there is increasing evidence that these receptors and their ligands might play a significant role in cancer biology. 4-(N-tibenzylpiperidin-4-yl-4iodobenzamide (4-IBP, a selective σ1, agonist, has been used to investigate whether this compound is able to modify: 1 in vitro the migration and proliferation of human cancer cells; 2 in vitro the sensitivity of human glioblastoma cells to cytotoxic drugs; and 3 in vivo in orthotopic glioblastoma and non-small cell lung carcinoma (NSCLC models the survival of mice coadministered cytotoxic agents. 4-IBP has revealed weak anti proliferative effects on human U373-MG glioblastoma and C32 melanoma cells but induced marked concentration-dependent decreases in the growth of human A549 NSCLC and PC3 prostate cancer cells. The compound was also significantly antimigratory in all four cancer cell lines. This may result, at least in U373-MG cells, from modifications to the actin cytoskeleton. 4-IBP modified the sensitivity of U373-MG cells in vitro to proapoptotic lomustin and proautophagic temozolomide, and markedly decreased the expression of two proteins involved in drug resistance: glucosylceramide synthase and Rho guanine nucleotide dissociation inhibitor. In vivo, 4-IBP increased the antitumor effects of temozolomide and irinotecan in immunodeficient mice that were orthotopically grafted with invasive cancer cells.

  13. BRCA1-deficient breast cancer cell lines are resistant to MEK inhibitors and show distinct sensitivities to 6-thioguanine.

    Science.gov (United States)

    Gu, Yuexi; Helenius, Mikko; Väänänen, Kristiina; Bulanova, Daria; Saarela, Jani; Sokolenko, Anna; Martens, John; Imyanitov, Evgeny; Kuznetsov, Sergey

    2016-06-17

    Germ-line or somatic inactivation of BRCA1 is a defining feature for a portion of human breast cancers. Here we evaluated the anti-proliferative activity of 198 FDA-approved and experimental drugs against four BRCA1-mutant (HCC1937, MDA-MB-436, SUM1315MO2, and SUM149PT) and four BRCA1-wild-type (MDA-MB-231, SUM229PE, MCF10A, and MCF7) breast cancer cell lines. We found that all BRCA1-mutant cell lines were insensitive to inhibitors of mitogen-activated protein kinase kinase 1 and 2 (MEK1/2) Selumetinib and Pimasertib in contrast to BRCA1-wildtype control cell lines. However, unexpectedly, only two BRCA1-mutant cell lines, HCC1937 and MDA-MB-436, were hypersensitive to a nucleotide analogue 6-thioguanine (6-TG). SUM149PT cells readily formed radiation-induced RAD51-positive nuclear foci indicating a functional homologous recombination, which may explain their resistance to 6-TG. However, the reason underlying 6-TG resistance of SUM1315MO2 cells remains unclear. Our data reveal a remarkable heterogeneity among BRCA1-mutant cell lines and provide a reference for future studies.

  14. Novel CD44 receptor targeting multifunctional “nano-eggs” based on double pH-sensitive nanoparticles for co-delivery of curcumin and paclitaxel to cancer cells and cancer stem cells

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Daquan, E-mail: cdq1981@126.com [Peking University, School of Pharmaceutical Sciences, Health Science Center (China); Wang, Guohua [China Academy of Chinese Medical Sciences, Institute of Chinese Materia Madica (China); Song, Weiguo [Shouguang Fukang Pharmceutial Co., Ltd. (China); Zhang, Qiang, E-mail: zqdodo@bjmu.edu.cn [Peking University, School of Pharmaceutical Sciences, Health Science Center (China)

    2015-10-15

    Most anticancer drugs cannot kill cancer stem cells (CSCs) effectively, which lead to the failure of anticancer chemotherapy, such as relapse and metastasis. In this study, we prepared a multifunctional oligosaccharides of hyaluronan (oHA) conjugates, oHA-histidine-menthone 1,2-glycerol ketal (oHM). The oHM conjugates possess pH-sensitive menthone 1,2-glycerol ketal (MGK) as hydrophobic moieties and oHA as the target of CD44 receptor. Anticancer drugs, curcumin(Cur) and paclitaxel(PTX), were loaded into oHM micelles via self-assembly. Then, oHM micelles were mineralized through controlled deposition of inorganic calcium and phosphate ions on the nanoparticular shell via a sequential addition method to fabricate the “nano-eggs.” The formed nano-eggs had a smaller size (120.6 ± 4.5 nm) than oHM micelles (158.6 ± 6.4 nm), indicating that mineralization made the appearance of compact nanoparticles. Interestingly, when the nano-eggs were put into the acidic conditions (pH 6.5), their outer shell(inorganic minerals) will be destroyed with the larger size, while the “nano-eggs” were stable under pH 7.4. For both nano-eggs and oHM micelles, the Cur and PTX were released in a sustained manner depending on the pH of the solution. However, the nano-eggs showed much lower released than the oHM micelles due to the dissolution of the inorganic minerals and pH-sensitive ketal at mildly acidic environments (pH 6.5). In vivo study, the nano-eggs could get to the tumor site more effectively than oHM micelles. CSCs were sorted by a side population assay from MDA-MB-231 breast cancer cell lines over-expressing CD44 receptors. Antitumor activity was also evaluated on MDA-MB-231 xenografts in nude mice. The antitumor efficacy indicated that nano-eggs with co-delivery of Cur and PTX produced the strongest antitumor efficacy, and nano-eggs showed strong activity against cancer stem cells. These double pH-sensitive nano-eggs may provide a promising strategy for drug

  15. Cancer stem cells and personalized cancer nanomedicine.

    Science.gov (United States)

    Gener, Petra; Rafael, Diana Fernandes de Sousa; Fernández, Yolanda; Ortega, Joan Sayós; Arango, Diego; Abasolo, Ibane; Videira, Mafalda; Schwartz, Simo

    2016-02-01

    Despite the progress in cancer treatment over the past years advanced cancer is still an incurable disease. Special attention is pointed toward cancer stem cell (CSC)-targeted therapies, because this minor cell population is responsible for the treatment resistance, metastatic growth and tumor recurrence. The recently described CSC dynamic phenotype and interconversion model of cancer growth hamper even more the possible success of current cancer treatments in advanced cancer stages. Accordingly, CSCs can be generated through dedifferentiation processes from non-CSCs, in particular, when CSC populations are depleted after treatment. In this context, the use of targeted CSC nanomedicines should be considered as a promising tool to increase CSC sensitivity and efficacy of specific anti-CSC therapies.

  16. Silencing of the SNARE protein NAPA sensitizes cancer cells to cisplatin by inducing ERK1/2 signaling, synoviolin ubiquitination and p53 accumulation.

    Science.gov (United States)

    Wu, Zchong-Zcho; Sun, Nian-Kang; Chien, Kun-Yi; Chao, Chuck C-K

    2011-12-01

    We found earlier that NAPA represents an anti-apoptotic protein that promotes resistance to cisplatin in cancer cells by inducing the degradation of the tumor suppressor p53. In the present study, we investigated the cellular mechanism underlying the degradation of p53 by NAPA. Knockdown of NAPA using short-hairpin RNA was shown to induce p53 accumulation and to sensitize HEK293 cells to cisplatin. On the other hand, this sensitization effect was not found in H1299 lung carcinoma cells which lack p53. Expression of exogenous p53 in H1299 cells was increased following knockdown of NAPA and these cells showed increased sensitivity to cisplatin-induced apoptosis. Notably, knockdown of NAPA induced the ubiquitination and degradation of the E3 ubiquitin ligase synoviolin and the accumulation of p53 in unstressed HEK293 cells. Conversely, NAPA overexpression decreased the ubiquitination and degradation of synoviolin, and reduced p53 protein level. Knockdown of NAPA disrupted the interaction between synoviolin and proteins that form the endoplasmic reticulum-associated degradation (ERAD) complex and in turn decreased the ability of this complex to ubiquitinate p53. In addition, knockdown of NAPA induced the activation of the MAPK kinases ERK, JNK and p38, but only inhibition of ERK reduced synoviolin ubiquitination and p53 accumulation. These results indicate that NAPA promotes resistance to cisplatin through synoviolin and the ERAD complex which together induce the degradation of p53 and thus prevent apoptosis. Based on these findings, we propose that the combination of cisplatin and knockdown of NAPA represents a novel and attractive strategy to eradicate p53-sensitive cancer cells.

  17. MicroRNA-143 replenishment re-sensitizes colorectal cancer cells harboring mutant, but not wild-type, KRAS to paclitaxel treatment.

    Science.gov (United States)

    Fei, Bing-Yuan; Wang, Xiu-Ying; Fang, Xue-Dong

    2016-05-01

    Colorectal cancer (CRC) global incidence is one of the highest among cancers. The KRAS gene has been shown as a robust biomarker for poor prognosis and drug resistance. MicroRNA-143 (miR-143) and let-7 are families of tumor suppressor microRNAs that are often downregulated in CRC, especially with coexistent KRAS mutations. In order to evaluate if miR-143 and/or let-7b replenishment would re-sensitize CRC cells to paclitaxel treatment, we investigated in effect of miR-143 and let-7b replenishments on sensitivity to paclitaxel treatment in KRAS mutant LoVo and wild-type SW48 CRC cell lines. Our results showed that miR-143, but not let-7b, increased sensitization of KRAS mutant tumor cells to paclitaxel. Furthermore, transfection of miR-143, but not let-7b, mimic negatively regulated the expression of mutant but not wild-type KRAS. Combination of miR-143 mimic and paclitaxel induced the onset of apoptosis, and reverted in vitro metastatic properties (migration and invasion) in KRAS mutant tumor cells. MiR-143 thus can be used as a chemosensitizer for the treatment of KRAS mutant tumors and warrants further investigations in in vitro and pre-clinical in vivo models.

  18. Sensitization of Cervical Cancer Cells to Cisplatin by Genistein: The Role of NFB and Akt/mTOR Signaling Pathways

    Directory of Open Access Journals (Sweden)

    K. Sahin

    2012-01-01

    Full Text Available Cervical cancer is among the top causes of death from cancer in women. Cisplatin-based chemotherapy has been shown to improve survival; however, cisplatin treatment is associated with toxicity to healthy cells. Genistein has been used as an adjunct to chemotherapy to enhance the activity of chemotherapeutic agents without causing increased toxicity. The present study was designed to investigate the effect of genistein (25 μM on antitumor activity of cisplatin (250 nM on HeLa cervical cancer cells. We have examined the alterations in expression of NF-B, p-mTOR, p-p70S6K1, p-4E-BP1, and p-Akt protein levels in response to treatment. The combination of 25 μM genistein with 250 nM cisplatin resulted in significantly greater growth inhibition (. Genistein enhanced the antitumor activity of cisplatin and reduced the expression of NF-B, p-mTOR, p-p70S6K1, p-4E-BP1, and p-Akt. The results in the present study suggest that genistein could enhance the activity of cisplatin via inhibition of NF-κB and Akt/mTOR pathways. Genistein is a promising nontoxic nutritional agent that may enhance treatment outcome in cervical cancer patients when given concomitantly with cisplatin. Clinical trials of genistein and cisplatin combination are warranted to test this hypothesis.

  19. Hispolon from Phellinus linteus induces apoptosis and sensitizes human cancer cells to the tumor necrosis factor-related apoptosis-inducing ligand through upregulation of death receptors.

    Science.gov (United States)

    Kim, Ji-Hun; Kim, Yu Chul; Park, Byoungduck

    2016-02-01

    The tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a potent anticancer agent possessing the ability to induce apoptosis in various cancer cells but not in non‑malignant cells. However, certain type of cancer cells are resistant to TRAIL‑induced apoptosis and some acquire resistance after the first treatment. So development of an agent that can reduce or avoid resistance in TRAIL‑induced apoptosis has garnered significant attention. The present study evaluated the anticancer potential of hispolon in TRAIL‑induced apoptosis and indicated hispolon can sensitize cancer cells to TRAIL. As the mechanism of action was examined, hispolon was found to activate caspase‑3, caspase‑8 and caspase‑9, while downregulating the expression of cell survival proteins such as cFLIP, Bcl‑2 and Bcl‑xL and upregulating the expression of Bax and truncated Bid. We also found hispolon induced death receptors in a non‑cell type‑specific manner. Upregulation of death receptors by hispolon was found to be p53-independent but linked to the induction of CAAT enhancer binding protein homologous protein (CHOP). Overall, hispolon was demonstrated to potentiate the apoptotic effects of TRAIL through downregulation of anti‑apoptotic proteins and upregulation of death receptors linked with CHOP and pERK elevation.

  20. 5. MUTAGEN SENSITIVITY AND DNA REPAIR CAPACITY (DRC) AS RISK FACTORS FOR NON-SMALL CELL LUNG CANCER

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@An alkaline single cell gel electrophoresis assay has been standardised by which mutagen sensitivity and DNA repair capacity (DRC) can be measured in cryopreserved peripheral blood lymphocytes following induction and repair of DNA damage induced by bleomycin. In an ongoing case-control study, we have applied this assay to Caucasian

  1. Size-based enrichment of exfoliated tumor cells in urine increases the sensitivity for DNA-based detection of bladder cancer.

    Directory of Open Access Journals (Sweden)

    Elin Andersson

    Full Text Available Bladder cancer is diagnosed by cystoscopy, a costly and invasive procedure that is associated with patient discomfort. Analysis of tumor-specific markers in DNA from sediments of voided urine has the potential for non-invasive detection of bladder cancer; however, the sensitivity is limited by low fractions and small numbers of tumor cells exfoliated into the urine from low-grade tumors. The purpose of this study was to improve the sensitivity for non-invasive detection of bladder cancer by size-based capture and enrichment of tumor cells in urine. In a split-sample set-up, urine from a consecutive series of patients with primary or recurrent bladder tumors (N = 189 was processed by microfiltration using a membrane filter with a defined pore-size, and sedimentation by centrifugation, respectively. DNA from the samples was analyzed for seven bladder tumor-associated methylation markers using MethyLight and pyrosequencing assays. The fraction of tumor-derived DNA was higher in the filter samples than in the corresponding sediments for all markers (p<0.000001. Across all tumor stages, the number of cases positive for one or more markers was 87% in filter samples compared to 80% in the corresponding sediments. The largest increase in sensitivity was achieved in low-grade Ta tumors, with 82 out of 98 cases positive in the filter samples (84% versus 74 out of 98 in the sediments (75%. Our results show that pre-analytic processing of voided urine by size-based filtration can increase the sensitivity for DNA-based detection of bladder cancer.

  2. Sensitization of Cancer Cells through Reduction of Total Akt and Downregulation of Salinomycin-Induced pAkt, pGSk3β, pTSC2, and p4EBP1 by Cotreatment with MK-2206

    Directory of Open Access Journals (Sweden)

    Ae-Ran Choi

    2014-01-01

    Full Text Available MK-2206 is an inhibitor of Akt activation. It has been investigated as an anticancer drug in clinical trials assessing the potential of pAkt targeting therapy. The purpose of this study was to identify conditions that increase the sensitivity of cancer cells to MK-2206. We found that the treatment of cancer cells with a high concentration of salinomycin (Sal reduced total Akt protein levels but increased activated Akt levels. When cancer cells were cotreated with MK-2206 and Sal, both pAkt and total Akt levels were reduced. Using microscopic observation, an assessment of cleaved PARP, FACS analysis of pre-G1 region, and Hoechst staining, we found that Sal increased apoptosis of MK-2206-treated cancer cells. These results suggest that cotreatment with MK-2206 and Sal sensitizes cancer cells via reduction of both pAkt and total Akt. Furthermore, cotreatment of cancer cells with Sal and MK-2206 reduced pp70S6K, pmTOR, and pPDK1 levels. In addition, Sal-induced activation of GSK3β, TSC2, and 4EBP1 was abolished by MK-2206 cotreatment. These results suggest that cotreatment using MK-2206 and Sal could be used as a therapeutic method to sensitize cancer cells through targeting of the PI3K/Akt/mTOR pathway. Our findings may contribute to the development of MK-2206-based sensitization therapies for cancer patients.

  3. Multifunctional gold coated thermo-sensitive liposomes for multimodal imaging and photo-thermal therapy of breast cancer cells

    Science.gov (United States)

    Rengan, Aravind Kumar; Jagtap, Madhura; de, Abhijit; Banerjee, Rinti; Srivastava, Rohit

    2013-12-01

    Plasmon resonant gold nanoparticles of various sizes and shapes have been extensively researched for their applications in imaging, drug delivery and photothermal therapy (PTT). However, their ability to degrade after performing the required function is essential for their application in healthcare. When combined with biodegradable liposomes, they appear to have better degradation capabilities. They degrade into smaller particles of around 5 nm that are eligible candidates for renal clearance. Distearoyl phosphatidyl choline : cholesterol (DSPC : CHOL, 8 : 2 wt%) liposomes have been synthesized and coated with gold by in situ reduction of chloro-auric acid. These particles of size 150-200 nm are analyzed for their stability, degradation capacity, model drug-release profile, biocompatibility and photothermal effects on cancer cells. It is observed that when these particles are subjected to low power continuous wave near infra-red (NIR) laser for more than 10 min, they degrade into small gold nanoparticles of size 5 nm. Also, the gold coated liposomes appear to have excellent biocompatibility and high efficiency to kill cancer cells through photothermal transduction. These novel materials are also useful in imaging using specific NIR dyes, thus exhibiting multifunctional properties for theranostics of cancer.Plasmon resonant gold nanoparticles of various sizes and shapes have been extensively researched for their applications in imaging, drug delivery and photothermal therapy (PTT). However, their ability to degrade after performing the required function is essential for their application in healthcare. When combined with biodegradable liposomes, they appear to have better degradation capabilities. They degrade into smaller particles of around 5 nm that are eligible candidates for renal clearance. Distearoyl phosphatidyl choline : cholesterol (DSPC : CHOL, 8 : 2 wt%) liposomes have been synthesized and coated with gold by in situ reduction of chloro-auric acid. These

  4. Genistein and daidzein induce cell proliferation and their metabolites cause oxidative DNA damage in relation to isoflavone-induced cancer of estrogen-sensitive organs.

    Science.gov (United States)

    Murata, Mariko; Midorikawa, Kaoru; Koh, Masashi; Umezawa, Kazuo; Kawanishi, Shosuke

    2004-03-09

    The soy isoflavones, genistein (5,7,4'-trihydroxyisoflavone) and daidzein (7,4'-dihydroxyisoflavone), are representative phytoestrogens that function as chemopreventive agents against cancers, cardiovascular disease, and osteoporosis. However, recent studies indicated that genistein and/or daidzein induced cancers of reproductive organs in rodents, such as the uterus and vulva. To clarify the molecular mechanisms underlying the induction of carcinogenesis by soy isoflavones, we examined the ability of genistein, daidzein, and their metabolites, 5,7,3',4'-tetrahydroxyisoflavone (orobol), 7,3',4'-trihydroxyisoflavone (7,3',4'-OH-IF), and 6,7,4'-trihydroxyisoflavone (6,7,4'-OH-IF), to cause DNA damage and cell proliferation. An E-screen assay revealed that genistein and daidzein enhanced proliferation of estrogen-sensitive breast cancer MCF-7 cells, while their metabolites had little or no effect. A surface plasmon resonance sensor showed that binding of isoflavone-liganded estrogen receptors (ER) to estrogen response elements (ERE) was largely consistent with cell proliferative activity of isoflavones. Orobol and 7,3',4'-OH-IF significantly increased 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG) formation in human mammary epithelial MCF-10A cells, while genistein, daidzein, and 6,7,4'-OH-IF did not. Experiments using isolated DNA revealed a metal-dependent mechanism of oxidative DNA damage induced by orobol and 7,3',4'-OH-IF. DNA damage was enhanced by the addition of endogenous reductant NADH, formed via the redox cycle. These findings suggest that oxidative DNA damage by isoflavone metabolites plays a role in tumor initiation and that cell proliferation by isoflavones via ER-ERE binding induces tumor promotion and/or progression, resulting in cancer of estrogen-sensitive organs.

  5. Differential sensitivities of trastuzumab (Herceptin)-resistant human breast cancer cells to phosphoinositide-3 kinase (PI-3K) and epidermal growth factor receptor (EGFR) kinase inhibitors.

    Science.gov (United States)

    Chan, Carmel T; Metz, Marianne Z; Kane, Susan E

    2005-05-01

    Her2 (erbB2/neu) is overexpressed in 25-30% of human breast cancers. Herceptin is a recombinant humanized Her2 antibody used to treat breast cancer patients with Her2 overexpression. Over a 5-month selection process, we isolated clones of BT474 (BT) human breast carcinoma cells (BT/Her(R)) that were resistant to Herceptin in vitro. In BT/Her(R) subclones, cell-surface, phosphorylated and total cellular Her2 protein remained high in the continuous presence of Herceptin. Likewise, the levels of cell-surface, phosphorylated, and total cellular Her3 and EGFR were either unchanged or only slightly elevated in BT/Her(R) subclones relative to BT cells. One BT/Her(R) subclone had substantially upregulated cell-surface EGFR, but this did not correlate with a higher relative resistance to Herceptin. In looking at the downstream PI-3K/Akt signaling pathway, phosphorylated and total Akt levels and Akt kinase activities were all sustained in BT/Her(R) subclones in the presence of Herceptin, but significantly downregulated in BT cells exposed to Herceptin. Whereas BT cells lost sensitivity to the PI-3K inhibitor LY294002 in the presence of Herceptin, BT/Her(R) subclones were equally sensitive to this agent in the presence and absence of Herceptin. This suggests that BT/Her(R) subclones acquired a Herceptin-resistant mechanism of PI-3K signaling. BT/Her(R) subclones were also sensitive to the EGFR kinase inhibitor AG1478 in the presence of Herceptin, to the same extent as BT cells. The BT/Her(R) subclones provide new insights into mechanisms of Herceptin resistance and suggest new treatment strategies in combination with other inhibitors targeted to signal transduction pathways.

  6. The AhR Ligand, TCDD, Regulates Androgen Receptor Activity Differently in Androgen-Sensitive versus Castration-Resistant Human Prostate Cancer Cells.

    Science.gov (United States)

    Ghotbaddini, Maryam; Powell, Joann B

    2015-07-06

    The reported biological effects of TCDD include induction of drug metabolizing enzymes, wasting syndrome and tumor promotion. TCDD elicits most of its effects through binding the aryl hydrocarbon receptor (AhR). TCDD induced degradation of AhR has been widely reported and requires ubiquitination of the protein. The rapid depletion of AhR following TCDD activation serves as a mechanism to modulate AhR mediated gene induction. In addition to inducing AhR degradation, TCDD has been reported to induce degradation of hormone receptors. The studies reported here, evaluate the effect of TCDD exposure on androgen receptor (AR) expression and activity in androgen-sensitive LNCaP and castration-resistant C4-2 prostate cancer cells. Our results show that TCDD exposure does not induce AhR or AR degradation in C4-2 cells. However, both AhR and AR are degraded in LNCaP cells following TCDD exposure. In addition, TCDD enhances AR phosphorylation and induces expression of AR responsive genes in LNCaP cells. Our data reveals that TCDD effect on AR expression and activity differs in androgen-sensitive and castration-resistant prostate cancer cell models.

  7. The AhR Ligand, TCDD, Regulates Androgen Receptor Activity Differently in Androgen-Sensitive versus Castration-Resistant Human Prostate Cancer Cells

    Directory of Open Access Journals (Sweden)

    Maryam Ghotbaddini

    2015-07-01

    Full Text Available The reported biological effects of TCDD include induction of drug metabolizing enzymes, wasting syndrome and tumor promotion. TCDD elicits most of its effects through binding the aryl hydrocarbon receptor (AhR. TCDD induced degradation of AhR has been widely reported and requires ubiquitination of the protein. The rapid depletion of AhR following TCDD activation serves as a mechanism to modulate AhR mediated gene induction. In addition to inducing AhR degradation, TCDD has been reported to induce degradation of hormone receptors. The studies reported here, evaluate the effect of TCDD exposure on androgen receptor (AR expression and activity in androgen-sensitive LNCaP and castration-resistant C4-2 prostate cancer cells. Our results show that TCDD exposure does not induce AhR or AR degradation in C4-2 cells. However, both AhR and AR are degraded in LNCaP cells following TCDD exposure. In addition, TCDD enhances AR phosphorylation and induces expression of AR responsive genes in LNCaP cells. Our data reveals that TCDD effect on AR expression and activity differs in androgen-sensitive and castration-resistant prostate cancer cell models.

  8. Prostate apoptosis response protein 4 sensitizes human colon cancer cells to chemotherapeutic 5-FU through mediation of an NFκB and microRNA network

    Directory of Open Access Journals (Sweden)

    Weirauch Matthew T

    2010-04-01

    BCL2 down-regulation and apoptosis by 5-FU. Conversely, bypassing Par-4 overexpression by direct knockdown of DROSHA expression in native HT29 cells increased miR-34a expression and 5-FU sensitivity. Conclusion Our findings suggest that the initiation of apoptotic sensitivity in colon cancer cells can be mediated by Par-4 binding to NFκB in the cytoplasm with consequential changes in the expression of microRNA pathway components.

  9. Regulation of deoxycytidine kinase expression and sensitivity to gemcitabine by micro-RNA 330 and promoter methylation in cancer cells.

    Science.gov (United States)

    Hodzic, Jasmina; Giovannetti, Elisa; Diosdado, Begoňa; Calvo, Begona Diosdado; Adema, A D; Peters, G J

    2011-12-01

    Deoxycytidine kinase (dCK) is essential for phosphorylation of natural deoxynucleosides and analogs, such as gemcitabine and cytarabine, two widely used anticancer compounds. Regulation of dCK is complex, including Ser-74 phosphorylation. We hypothesized that dCK could be regulated by two additional mechanisms: micro-RNA (miRNA) and promoter methylation. Methylation-specific PCR (MSP) revealed methylation of the 3' GC box in three out of six cancer cell lines. The 3' GC box is located at the dCK promoter region. The methylation status was related to dCK mRNA expression. TargetScan and miRanda prediction algorithms revealed several possible miRNAs targeting dCK and identified miR-330 (micro-RNA 330) as the one conserved between the human, the chimpanzee, and the rhesus monkey genomes. Expression of miR-330 in various colon and lung cancer cell lines, as measured by QRT-PCR, varied five-fold between samples and correlated with in-vitro gemcitabine resistance (R = 0.82, p = 0.04). Exposure to gemcitabine also appeared to influence miR-330 levels in these cell lines. Furthermore, in our cell line panel, miR-330 expression negatively correlated with dCK mRNA expression (R = 0.74), suggesting a role of miR-330 in post-transcriptional regulation of dCK. In conclusion, the 3' GC box and miR-330 may regulate dCK expression in cancer cells.

  10. Curcumin sensitizes human gastric cancer cells to 5-fluorouracil through inhibition of the NFκB survival-signaling pathway

    Directory of Open Access Journals (Sweden)

    Kang Y

    2016-12-01

    Full Text Available Yanting Kang,1,2,* Wanle Hu,3,* Encheng Bai,1,2 Hailun Zheng,1 Zhiguo Liu,1 Jianzhang Wu,1 Rong Jin,2 Chengguang Zhao,1 Guang Liang1 1Chemical Biology Research Center, School of Pharmaceutical Sciences, 2Department of Epidemiology, First Affiliated Hospital, 3Department of Coloproctology, Second Affiliated Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China *These authors contributed equally to this work Abstract: Fluorouracil (5-FU is the most commonly used chemotherapeutic agent for gastric cancer (GC. However, the occurrence of resistance to 5-FU treatment poses a major problem for its clinical efficacy. In this study, we found that the NFκB-signaling pathway can mediate 5-FU resistance in GC cells. We developed a 5-FU-resistant GC cell line named SGCR/5-FU and found that the 5-FU-induced resistance increased cytosolic IκBα degradation and promoted NFκB nuclear translocation in GC cells. These findings were further confirmed by the activation of the NFκB survival-signaling pathway in clinical specimens. Curcumin, a natural compound, can reverse 5-FU resistance and inhibits proliferation in GC cells by downregulating the NFκB-signaling pathway. Moreover, it can also decrease the expression level of TNFα messenger RNA. Flow cytometry and Western blot analysis results showed that the combination of curcumin and 5-FU caused synergistic inhibition of growth and induction of potent apoptosis in the resistant cancer cell lines in vitro. In conclusion, our results demonstrate that the combination of 5-FU and curcumin could be further developed as a potential therapy for human GC. Keywords: 5-FU, curcumin, NFκB, drug resistance, gastric cancer

  11. Use of metformin alone is not associated with survival outcomes of colorectal cancer cell but AMPK activator AICAR sensitizes anticancer effect of 5-fluorouracil through AMPK activation.

    Directory of Open Access Journals (Sweden)

    Xinbing Sui

    Full Text Available Colorectal cancer (CRC is still the third most common cancer and the second most common causes of cancer-related death around the world. Metformin, a biguanide, which is widely used for treating diabetes mellitus, has recently been shown to have a suppressive effect on CRC risk and mortality, but not all laboratory studies suggest that metformin has antineoplastic activity. Here, we investigated the effect of metformin and AMPK activator AICAR on CRC cells proliferation. As a result, metformin did not inhibit cell proliferation or induce apoptosis for CRC cell lines in vitro and in vivo. Different from metformin, AICAR emerged antitumor activity and sensitized anticancer effect of 5-FU on CRC cells in vitro and in vivo. In further analysis, we show that AMPK activation may be a key molecular mechanism for the additive effect of AICAR. Taken together, our results suggest that metformin has not antineoplastic activity for CRC cells as a single agent but AMPK activator AICAR can induce apoptosis and enhance the cytotoxic effect of 5-FU through AMPK activation.

  12. p53 and p21 determine the sensitivity of noscapine-induced apoptosis in colon cancer cells.

    Science.gov (United States)

    Aneja, Ritu; Ghaleb, Amr M; Zhou, Jun; Yang, Vincent W; Joshi, Harish C

    2007-04-15

    We have previously discovered the naturally occurring antitussive alkaloid noscapine as a tubulin-binding agent that attenuates microtubule dynamics and arrests mammalian cells at mitosis via activation of the c-Jun NH(2)-terminal kinase pathway. It is well established that the p53 protein plays a crucial role in the control of tumor cell response to chemotherapeutic agents and DNA-damaging agents; however, the relationship between p53-driven genes and drug sensitivity remains controversial. In this study, we compared chemosensitivity, cell cycle distribution, and apoptosis on noscapine treatment in four cell lines derived from the colorectal carcinoma HCT116 cells: p53(+/+) (p53-wt), p53(-/-) (p53-null), p21(-/-) (p21-null), and BAX(-/-) (BAX-null). Using these isogenic variants, we investigated the roles of p53, BAX, and p21 in the cellular response to treatment with noscapine. Our results show that noscapine treatment increases the expression of p53 over time in cells with wild-type p53 status. This increase in p53 is associated with an increased apoptotic BAX/Bcl-2 ratio consistent with increased sensitivity of these cells to apoptotic stimuli. Conversely, loss of p53 and p21 alleles had a counter effect on both BAX and Bcl-2 expression and the p53-null and p21-null cells were significantly resistant to the antiproliferative and apoptotic effects of noscapine. All but the p53-null cells displayed p53 protein accumulation in a time-dependent manner on noscapine treatment. Interestingly, despite increased levels of p53, p21-null cells were resistant to apoptosis, suggesting a proapoptotic role of p21 and implying that p53 is a necessary but not sufficient condition for noscapine-mediated apoptosis.

  13. Radiation survival parameters of antineoplastic drug-sensitive and -resistant human ovarian cancer cell lines and their modification by buthionine sulfoximine

    Energy Technology Data Exchange (ETDEWEB)

    Louie, K.G.; Behrens, B.C.; Kinsella, T.J.; Hamilton, T.C.; Grotzinger, K.R.; McKoy, W.M.; Winker, M.A.; Ozols, R.F.

    1985-05-01

    The optimum integration of chemotherapy and irradiation is of potential clinical significance in the treatment of ovarian cancer. A series of human ovarian cancer cell lines have been developed in which dose-response relationships to standard anticancer drugs have been determined, and the patterns of cross-resistance between these drugs and irradiation have been established. By stepwise incubation with drugs, sublines of A2780, a drug-sensitive cell line, have been made 100-fold, 10-fold, and 10-fold more resistant to Adriamycin (2780AD), melphalan (2780ME), and cisplatin (2780CP). Two additional cell lines, NIH:OVCAR-3nu(Ag+) and NIH:OVCAR-4(Ag+), were established from drug-refractory patients. 2780ME, 2780CP, OVCAR-3nu(Ag+), and OVCAR-4(Ag+) are all cross-resistant to irradiation, with DOS of 146, 187, 143, and 203, respectively. However, 2780AD remains sensitive to radiation, with a DO of 111, which is similar to that of A2780 (101). Glutathione (GSH) levels are elevated in 2780ME, 2780CP, OVCAR-3nu(Ag+), and OVCAR-4(Ag+) to 4.58, 6.13, 12.10, and 15.14 nmol/10(6) cells as compared to A2780, with 1.89 nmol/10(6) cells. However, the GSH level in 2780AD is only minimally higher than that in A2780 (2.94 nmol/10(6) cells). Buthionine sulfoximine, a specific inhibitor of GSH synthesis, significantly increases the radiation sensitivity of 2780ME (changing the DO from 143 to 95) and 2780CP to a lesser extent, suggesting that intracellular GSH levels may play an important role in the radiation response of certain neoplastic cells.

  14. Wild-type and specific mutant androgen receptor mediates transcription via 17β-estradiol in sex hormone-sensitive cancer cells.

    Science.gov (United States)

    Susa, Takao; Ikaga, Reina; Kajitani, Takashi; Iizuka, Masayoshi; Okinaga, Hiroko; Tamamori-Adachi, Mimi; Okazaki, Tomoki

    2015-07-01

    We previously encountered regulatory processes wherein dihydrotestosterone (DHT) exerted its inhibitory effect on parathyroid hormone-related protein (PTHrP) gene repression through the estrogen receptor (ER)α, but not the androgen receptor (AR), in breast cancer MCF-7 cells. Here, we investigated whether such aberrant ligand-nuclear receptor (NR) interaction is present in prostate cancer LNCaP cells. First, we confirmed that LNCaP cells expressed large amounts of AR at negligible levels of ERα/β or progesterone receptor. Both suppression of PTHrP and activation of prostate-specific antigen genes were observed after independent administration of 17β-estradiol (E2), DHT, or R5020. Consistent with the notion that the LNCaP AR lost its ligand specificity due to a mutation (Thr-Ala877), experiments with siRNA targeting the respective NR revealed that the AR monopolized the role of the mediator of shared hormone-dependent regulation, which was invariably associated with nuclear translocation of this mutant AR. Microarray analysis of gene regulation by DHT, E2, or R5020 disclosed that more than half of the genes downstream of the AR (Thr-Ala877) overlapped in the LNCaP cells. Of particular interest, we realized that the AR (wild-type [wt]) and AR (Thr-Ala877) were equally responsible for the E2-AR interactions. Fluorescence microscopy experiments demonstrated that both EGFP-AR (wt) and EGFP-AR (Thr-Ala877) were exclusively localized within the nucleus after E2 or DHT treatment. Furthermore, reporter assays revealed that some other cancer cells exhibited aberrant E2-AR (wt) signaling similar to that in the LNCaP cells. We herein postulate the presence of entangled interactions between wt AR and E2 in certain hormone-sensitive cancer cells.

  15. Inhibition of mitogen activated protein kinases increases the sensitivity of A549 lung cancer cells to the cytotoxicity induced by a kava chalcone analog.

    Science.gov (United States)

    Warmka, Janel K; Solberg, Eric L; Zeliadt, Nicholette A; Srinivasan, Balasubramanian; Charlson, Aaron T; Xing, Chengguo; Wattenberg, Elizabeth V

    2012-08-03

    We are interested in investigating the biological activity of chalcones, a major class of compounds found in the beverage kava, in order to develop potent and selective chemopreventive candidates. Consumption of kava in the South Pacific Islands is inversely correlated with cancer incidence, even among smokers. Accordingly, chalcones have anti-cancer activities in animal and cell culture models. To investigate signaling pathways that affect chalcone action we studied a potent analog, (E)-3-(3-hydroxy-4-methoxyphenyl)-1-(3,4,5-trimethoxyphenyl)prop-2-en-1-one (chalcone-24). Chalcone-24 was selected from a series of chalcone analogs that were synthesized based on the structures derived from flavokawain compounds found in kava, and screened in A549 lung cancer cells for induction of cytotoxicity and inhibition of NF-κB, a transcription factor associated with cell survival. Incubation of A549 cells with chalcone-24 resulted in a dose-dependent inhibition of cell viability, inhibition of NF-κB, activation of caspases, and activation of extracellular signal regulated kinase 1/2 (ERK1/2) and c-Jun N-terminal kinase (JNK); ERK1/2 and JNK are mitogen activated protein kinases that play central roles in regulating cell fate. Pharmacological inhibitors of ERK1/2 or JNK increased the sensitivity of A549 cells to chalcone-24-induced cytotoxicity, without affecting NF-κB or caspase activity. These results will help refine the synthesis of chalcone analogs to maximize the combination of actions required to prevent and treat cancer.

  16. Sensitization of human colon cancer cells to sodium butyrate-induced apoptosis by modulation of sphingosine kinase 2 and protein kinase D

    Energy Technology Data Exchange (ETDEWEB)

    Xiao, Min [Department of Occupational Health and Occupational Medicine, School of Public Health and Tropical Medicine, Southern Medical University, Guangzhou 510515 (China); Liu, Yungang [Department of Toxicology, School of Public Health and Tropical Medicine, Southern Medical University, Guangzhou 510515 (China); Zou, Fei, E-mail: ZouFeiMed@gmail.com [Department of Occupational Health and Occupational Medicine, School of Public Health and Tropical Medicine, Southern Medical University, Guangzhou 510515 (China)

    2012-01-01

    Sphingosine kinases (SphKs) have been recognized as important proteins regulating cell proliferation and apoptosis. Of the two isoforms of SphK (SphK1 and SphK2), little is known about the functions of SphK2. Sodium butyrate (NaBT) has been established as a promising chemotherapeutic agent, but the precise mechanism for its effects is unknown. In this study, we investigated the role of SphK2 in NaBT-induced apoptosis of HCT116 colon cancer cells. The results indicated that following NaBT treatment SphK2 was translocated from the nucleus to the cytoplasm, leading to its accumulation in the cytoplasm; in the meantime, only mild apoptosis occurred. However, downregulation of SphK2 resulted in sensitized apoptosis, and overexpression of SphK2 led to even lighter apoptosis; these strongly indicate an inhibitory role of SphK2 in cell apoptosis induced by NaBT. After knocking down protein kinase D (PKD), another protein reported to be critical in cell proliferation/apoptosis process, by using siRNA, blockage of cytoplasmic accumulation of SphK2 and sensitized apoptosis following NaBT treatment were observed. The present study suggests that PKD and SphK2 may form a mechanism for the resistance of cancer cells to tumor chemotherapies, such as HCT116 colon cancer cells to NaBT, and these two proteins may become molecular targets for designation of new tumor-therapeutic drugs. -- Highlights: Black-Right-Pointing-Pointer In the present study sodium butyrate (10 mM) induced mild apoptosis of cancer cells. Black-Right-Pointing-Pointer The apoptosis was negatively regulated by cytoplasmic Sphingosine Kinase 2 (SphK2). Black-Right-Pointing-Pointer Translocation of SphK2 from nucleus to cytoplasm was mediated by protein kinase D. Black-Right-Pointing-Pointer Downregulation of SphK2 or protein kinase D leads to sensitized cell apoptosis.

  17. Sensitive electrochemical aptamer cytosensor for highly specific detection of cancer cells based on the hybrid nanoelectrocatalysts and enzyme for signal amplification.

    Science.gov (United States)

    Sun, Duanping; Lu, Jing; Zhong, Yuwen; Yu, Yanyan; Wang, Yu; Zhang, Beibei; Chen, Zuanguang

    2016-01-15

    Human cancer is becoming a leading cause of death in the world and the development of a straightforward strategy for early detection of cancer is urgently required. Herein, a sandwich-type electrochemical aptamer cytosensor was developed for detection of human liver hepatocellular carcinoma cells (HepG2) based on the hybrid nanoelectrocatalysts and enzyme for signal amplification. The thiolated TLS11a aptamers were used as a selective bio-recognition element, attached to the gold nanoparticles (AuNPs) modified the glassy carbon electrode (GCE) surface. Meanwhile, the electrochemical nanoprobes were fabricated through the G-quadruplex/hemin/aptamer complexes and horseradish peroxidase (HRP) immobilized on the surfaces of Au@Pd core-shell nanoparticle-modified magnetic Fe3O4/MnO2 beads (Fe3O4/MnO2/Au@Pd). After the target cells were captured, the hybrid nanoprobes were further assembled to form an aptamer-cell-nanoprobes sandwich-like system on the electrode surface. Then, hybrid Fe3O4/MnO2/Au@Pd nanoelectrocatalysts, G-quadruplex/hemin HRP-mimicking DNAzymes and the natural HRP enzyme efficiently catalyzed the oxidation of hydroquinone (HQ) with H2O2, amplifying the electrochemical signals and improving the detection sensitivity. This electrochemical cytosensor delivered a wide detection range of 1×10(2)-1×10(7)cellsmL(-1), high sensitivity with a low detection limit of 15cellsmL(-1), good selectivity and repeatability. Finally, an electrochemical reductive desorption method was performed to break gold-thiol bond and desorb the components on the AuNPs/GCE for regenerating the cytosensor. These results have demonstrated that the electrochemical cytosensor has the potential to be a feasible tool for cost-effective cancer cell detection in early cancer diagnosis.

  18. Differential cellular responses induced by dorsomorphin and LDN-193189 in chemotherapy-sensitive and chemotherapy-resistant human epithelial ovarian cancer cells.

    Science.gov (United States)

    Ali, Jennifer L; Lagasse, Brittany J; Minuk, Ainsley J; Love, Allison J; Moraya, Amani I; Lam, Linda; Arthur, Gilbert; Gibson, Spencer B; Morrison, Ludivine Coudière; Werbowetski-Ogilvie, Tamra E; Fu, Yangxin; Nachtigal, Mark W

    2015-03-01

    Inherent or acquired drug resistance is a major contributor to epithelial ovarian cancer (EOC) mortality. Novel drugs or drug combinations that produce EOC cell death or resensitize drug resistant cells to standard chemotherapy may improve patient treatment. After conducting drug tolerability studies for the multikinase inhibitors dorsomorphin (DM) and it is structural analogue LDN-193189 (LDN), these drugs were tested in a mouse intraperitoneal xenograft model of EOC. DM significantly increased survival, whereas LDN showed a trend toward increased survival. In vitro experiments using cisplatin (CP)-resistant EOC cell lines, A2780-cp or SKOV3, we determined that pretreatment or cotreatment with DM or LDN resensitized cells to the killing effect of CP or carboplatin (CB). DM was capable of blocking EOC cell cycle and migration, whereas LDN produced a less pronounced effect on cell cycle and no effect on migration. Subsequent analyses using primary human EOC cell samples or additional established EOC cells lines showed that DM or LDN induced a dose-dependent autophagic or cell death response, respectively. DM induced a characteristic morphological change with the appearance of numerous LC3B-containing acidic vacuoles and an increase in LC3BII levels. This was coincident with a decrease in cell growth and the altered cell cycle consistent with DM-induced cytostasis. By contrast, LDN produced a caspase 3-independent, reactive oxygen species-dependent cell death. Overall, DM and LDN possess drug characteristics suitable for adjuvant agents used to treat chemotherapy-sensitive and -resistant EOC.

  19. Sensitization of human colon cancer cells to sodium butyrate-induced apoptosis by modulation of sphingosine kinase 2 and protein kinase D.

    Science.gov (United States)

    Xiao, Min; Liu, Yungang; Zou, Fei

    2012-01-01

    Sphingosine kinases (SphKs) have been recognized as important proteins regulating cell proliferation and apoptosis. Of the two isoforms of SphK (SphK1 and SphK2), little is known about the functions of SphK2. Sodium butyrate (NaBT) has been established as a promising chemotherapeutic agent, but the precise mechanism for its effects is unknown. In this study, we investigated the role of SphK2 in NaBT-induced apoptosis of HCT116 colon cancer cells. The results indicated that following NaBT treatment SphK2 was translocated from the nucleus to the cytoplasm, leading to its accumulation in the cytoplasm; in the meantime, only mild apoptosis occurred. However, downregulation of SphK2 resulted in sensitized apoptosis, and overexpression of SphK2 led to even lighter apoptosis; these strongly indicate an inhibitory role of SphK2 in cell apoptosis induced by NaBT. After knocking down protein kinase D (PKD), another protein reported to be critical in cell proliferation/apoptosis process, by using siRNA, blockage of cytoplasmic accumulation of SphK2 and sensitized apoptosis following NaBT treatment were observed. The present study suggests that PKD and SphK2 may form a mechanism for the resistance of cancer cells to tumor chemotherapies, such as HCT116 colon cancer cells to NaBT, and these two proteins may become molecular targets for designation of new tumor-therapeutic drugs.

  20. Silencing of MicroRNA-21 confers the sensitivity to tamoxifen and fulvestrant by enhancing autophagic cell death through inhibition of the PI3K-AKT-mTOR pathway in breast cancer cells.

    Science.gov (United States)

    Yu, Xinfeng; Li, Ruilian; Shi, Wenna; Jiang, Tao; Wang, Yufei; Li, Cong; Qu, Xianjun

    2016-02-01

    Tamoxifen (TAM) and fulvestrant (FUL) represent the major adjuvant therapy to estrogen receptor-alpha positive (ER(+)) breast cancer patients. However, endocrine resistance to TAM and FUL is a great impediment for successful treatment. We hypothesized that miR-21 might alter the sensitivity of breast cancer cells to TAM or FUL by regulating cell autophagy. Using the ER(+) breast cancer cells, we knockdown miR-21.by transfection with miR-21 inhibitor, then the cells were exposed to TAM or FUL and the percentages of apoptosis and autophagy were determined. Knockdown of miR-21 significantly increased the TAM or FUL-induced apoptosis in ER(+) breast cancer cells. Further, silencing of miR-21 in MCF-7 cells enhanced cell autophagy at both basal and TAM or FUL-induced level. The increase of autophagy in miR-21-knockdown MCF-7 cells was also indicated by increase of beclin-1, LC3-II and increased GFP-LC3 dots. Importantly, knockdown of miR-21 contributed to autophagic cell death, which is responsible for part of TAM induced cell death in miR-21 inhibitor-transfected cells. Further analysis suggested that miR-21 inhibitor enhance autophagic cell death through inhibition of PI3K-AKT-mTOR pathway. MiR-21 coordinated the function of autophagy and apoptosis by targeting Phosphatase and tensin homolog (PTEN) through inhibition of PI3K-AKT-mTOR pathway. In conclusion, silencing of miR-21 increased the sensitivity of ER(+) breast cancer cells to TAM or FUL by increasing autophagic cell death. Targeting autophagy-related miRNAs is a potential strategy for overcoming endocrine resistance to TAM and FUL.

  1. Expression of domains for protein-protein interaction of nucleotide excision repair proteins modifies cancer cell sensitivity to platinum derivatives and genomic stability.

    Science.gov (United States)

    Jordheim, Lars Petter; Cros-Perrial, Emeline; Matera, Eva-Laure; Bouledrak, Karima; Dumontet, Charles

    2014-10-01

    Nucleotide excision repair (NER) is involved in the repair of DNA damage caused by platinum derivatives and has been shown to decrease the cytotoxic activity of these drugs. Because protein-protein interactions are essential for NER activity, we transfected human cancer cell lines (A549 and HCT116) with plasmids coding the amino acid sequences corresponding to the interacting domains between excision repair cross-complementation group 1 (ERCC1) and xeroderma pigmentosum, complementation group A (XPA), as well as ERCC1 and xeroderma pigmentosum, complementation group F (XPF), all NER proteins. Using the 3-(4,5-dimethyl-2 thiazoyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay and annexin V staining, we showed that transfected A549 cells were sensitized 1.2-2.2-fold to carboplatin and that transfected HCT116 cells were sensitized 1.4-5.4-fold to oxaliplatin in vitro. In addition, transfected cells exhibited modified in vivo sensitivity to the same drugs. Finally, in particular cell models of the interaction between ERCC1 and XPF, DNA repair was decreased, as evidenced by increased phosphorylation of the histone 2AX after exposure to mitomycin C, and genomic instability was increased, as determined by comparative genomic hybridization studies. The results indicate that the interacting peptides act as dominant negatives and decrease NER activity through inhibition of protein-protein interactions.

  2. Integrated proteomic and N-glycoproteomic analyses of doxorubicin sensitive and resistant ovarian cancer cells reveal glycoprotein alteration in protein abundance and glycosylation.

    Science.gov (United States)

    Ji, Yanlong; Wei, Shasha; Hou, Junjie; Zhang, Chengqian; Xue, Peng; Wang, Jifeng; Chen, Xiulan; Guo, Xiaojing; Yang, Fuquan

    2017-01-06

    Ovarian cancer is one of the most common cancer among women in the world, and chemotherapy remains the principal treatment for patients. However, drug resistance is a major obstacle to the effective treatment of ovarian cancers and the underlying mechanism is not clear. An increased understanding of the mechanisms that underline the pathogenesis of drug resistance is therefore needed to develop novel therapeutics and diagnostic. Herein, we report the comparative analysis of the doxorubicin sensitive OVCAR8 cells and its doxorubicin-resistant variant NCI/ADR-RES cells using integrated global proteomics and N-glycoproteomics. A total of 1525 unique N-glycosite-containing peptides from 740 N-glycoproteins were identified and quantified, of which 253 N-glycosite-containing peptides showed significant change in the NCI/ADR-RES cells. Meanwhile, stable isotope labeling by amino acids in cell culture (SILAC) based comparative proteomic analysis of the two ovarian cancer cells led to the quantification of 5509 proteins. As about 50% of the identified N-glycoproteins are low-abundance membrane proteins, only 44% of quantified unique N-glycosite-containing peptides had corresponding protein expression ratios. The comparison and calibration of the N-glycoproteome versus the proteome classified 14 change patterns of N-glycosite-containing peptides, including 8 up-regulated N-glycosite-containing peptides with the increased glycosylation sites occupancy, 35 up-regulated N-glycosite-containing peptides with the unchanged glycosylation sites occupancy, 2 down-regulated N-glycosite-containing peptides with the decreased glycosylation sites occupancy, 46 down-regulated N-glycosite-containing peptides with the unchanged glycosylation sites occupancy. Integrated proteomic and N-glycoproteomic analyses provide new insights, which can help to unravel the relationship of N-glycosylation and multidrug resistance (MDR), understand the mechanism of MDR, and discover the new diagnostic and

  3. Intracellular delivery of recombinant arginine deiminase (rADI) by heparin-binding hemagglutinin adhesion peptide restores sensitivity in rADI-resistant cancer cells.

    Science.gov (United States)

    Wu, Fe-Lin Lin; Yeh, Tzyy-Harn; Chen, Ying-Luen; Chiu, Yu-Chin; Cheng, Ju-Chen; Wei, Ming-Feng; Shen, Li-Jiuan

    2014-08-04

    Recombinant arginine deiminase (rADI) has been used in clinical trials for arginine-auxotrophic cancers. However, the emergence of rADI resistance, due to the overexpression of argininosuccinate synthetase (AS), has introduced an obstacle in its clinical application. Here, we have proposed a strategy for the intracellular delivery of rADI, which depletes both extracellular and intracellular arginine, to restore the sensitivity of rADI-resistant cancer cells. In this study, the C terminus of heparin-binding hemagglutinin adhesion protein from Mycobacterium tuberculosis (HBHAc), which contains 23 amino acids, was used to deliver rADI into rADI-resistant human breast adenocarcinoma cells (MCF-7). Chemical conjugates (l- and d-HBHAc-SPDP-rADI) and a recombinant fusion protein (rHBHAc-ADI) were produced. l- and d-HBHAc-SPDP-rADI showed a significantly higher cellular uptake of rADI by MCF-7 cells compared to that of rADI alone. Cell viability was significantly decreased in a dose-dependent manner in response to l- and d-HBHAc-SPDP-rADI treatments. In addition, the ratio of intracellular concentration of citrulline to arginine in cells treated with l- and d-HBHAc-SPDP-rADI was significantly increased by 1.4- and 1.7-fold, respectively, compared with that obtained in cells treated with rADI alone (p < 0.001). Similar results were obtained with the recombinant fusion protein rHBHAc-ADI. Our study demonstrates that the increased cellular uptake of rADI by HBHAc modification can restore the sensitivity of rADI treatment in MCF-7 cells. rHBHAc-ADI may represent a novel class of antitumor enzyme with an intracellular mechanism that is independent of AS expression.

  4. Silencing Prx1 and/or Prx5 sensitizes human esophageal cancer cells to ionizing radiation and increases apoptosis via intracellular ROS accumulation

    Institute of Scientific and Technical Information of China (English)

    Mai-cang GAO; Xiao-di JIA; Qi-fei WU; Yan CHENG; Fen-rong CHEN; Jun ZHANG

    2011-01-01

    Aim:To investigate whether down-regulation of peroxiredoxin 1(Prx1)and/or peroxiredoxin 5(Prx5)sensitizes human esophageal cancer cells to ionizing radiation(IR).Methods:Human esophageal carcinoma celllines Eca-109 and TE-1 were used.Prx mRNA expression profiles in Eca-109 and TE-1cells were determined using RT-PCR.Two highly expressed isoforms of Prxs,Prx1 and Prx5,were silenced by RNA interference(RNAi).Following IR,intracellular reactive oxygen species(ROS)and apoptosis were measured using flow cytometry,the activities of catalase,superoxide dismutase and glutathione peroxidase were measured,and the radiosensjtjzjng effect of RNAi was observed.Tumor xenograft model was also used to examine the radiOsensitizing effect of RNAi in vivo.Results:Down-regulation of Prx1 and/or Prx5 by RNAi does not alter the activities of catalase, superoxide dismutase and glutathione peroxidase,but made human tumor cells more sensitive to IR-induced apoptosis both fn vitro and in vivO.When the two isoforms were decreased simultaneously,intracellular ROS and apoptosis significantly increased after IR.Conclusion:Silencing Prx1 and/or Prx5 by RNAi sensitizes human Eca-109 and TE-1 cells to IR, and the intracellular ROS accumulation may contribute to the radiosensitizing effect of the RNAi.

  5. Insulin-Sensitizers, Polycystic Ovary Syndrome and Gynaecological Cancer Risk

    Directory of Open Access Journals (Sweden)

    Rosa Lauretta

    2016-01-01

    Full Text Available Preclinical, early phase clinical trials and epidemiological evidence support the potential role of insulin-sensitizers in cancer prevention and treatment. Insulin-sensitizers improve the metabolic and hormonal profile in PCOS patients and may also act as anticancer agents, especially in cancers associated with hyperinsulinemia and oestrogen dependent cancers. Several lines of evidence support the protection against cancer exerted by dietary inositol, in particular inositol hexaphosphate. Metformin, thiazolidinediones, and myoinositol postreceptor signaling may exhibit direct inhibitory effects on cancer cell growth. AMPK, the main molecular target of metformin, is emerging as a target for cancer prevention and treatment. PCOS may be correlated to an increased risk for developing ovarian and endometrial cancer (up to threefold. Several studies have demonstrated an increase in mortality rate from ovarian cancer among overweight/obese PCOS women compared with normal weight women. Long-term use of metformin has been associated with lower rates of ovarian cancer. Considering the evidence supporting a higher risk of gynaecological cancer in PCOS women, we discuss the potential use of insulin-sensitizers as a potential tool for chemoprevention, hypothesizing a possible rationale through which insulin-sensitizers may inhibit tumourigenesis.

  6. Insulin-Sensitizers, Polycystic Ovary Syndrome and Gynaecological Cancer Risk

    Science.gov (United States)

    Lauretta, Rosa; Lanzolla, Giulia; Vici, Patrizia; Mariani, Luciano; Moretti, Costanzo

    2016-01-01

    Preclinical, early phase clinical trials and epidemiological evidence support the potential role of insulin-sensitizers in cancer prevention and treatment. Insulin-sensitizers improve the metabolic and hormonal profile in PCOS patients and may also act as anticancer agents, especially in cancers associated with hyperinsulinemia and oestrogen dependent cancers. Several lines of evidence support the protection against cancer exerted by dietary inositol, in particular inositol hexaphosphate. Metformin, thiazolidinediones, and myoinositol postreceptor signaling may exhibit direct inhibitory effects on cancer cell growth. AMPK, the main molecular target of metformin, is emerging as a target for cancer prevention and treatment. PCOS may be correlated to an increased risk for developing ovarian and endometrial cancer (up to threefold). Several studies have demonstrated an increase in mortality rate from ovarian cancer among overweight/obese PCOS women compared with normal weight women. Long-term use of metformin has been associated with lower rates of ovarian cancer. Considering the evidence supporting a higher risk of gynaecological cancer in PCOS women, we discuss the potential use of insulin-sensitizers as a potential tool for chemoprevention, hypothesizing a possible rationale through which insulin-sensitizers may inhibit tumourigenesis. PMID:27725832

  7. Dye Sensitized Solar Cell, DSSC

    Directory of Open Access Journals (Sweden)

    Pongsatorn Amornpitoksuk

    2003-07-01

    Full Text Available A dye sensitized solar cell is a new type of solar cell. The operating system of this solar cell type is similar to plant’s photosynthesis process. The sensitizer is available for absorption light and transfer electrons to nanocrystalline metal oxide semiconductor. The ruthenium(II complexes with polypyridyl ligands are usually used as the sensitizers in solar cell. At the present time, the complex of [Ru(2,2',2'’-(COOH3- terpy(NCS3] is the most efficient sensitizer. The total photon to current conversion efficiency was approximately 10% at AM = 1.5.

  8. Hormone resistance in two MCF-7 breast cancer cell lines is associated with reduced mTOR signaling, decreased glycolysis and increased sensitivity to cytotoxic drugs

    Directory of Open Access Journals (Sweden)

    Euphemia Yee Leung

    2014-09-01

    Full Text Available The mTOR pathway is a key regulator of multiple cellular signaling pathways and is a potential target for therapy. We have previously developed two hormone-resistant sub-lines of the MCF-7 human breast cancer line, designated TamC3 and TamR3, which were characterized by reduced mTOR signaling, reduced cell volume and resistance to mTOR inhibition. Here we show that these lines exhibit increased sensitivity to carboplatin, oxaliplatin, 5-fluorouracil, camptothecin, doxorubicin, paclitaxel, docetaxel and hydrogen peroxide. The mechanisms underlying these changes have not yet been characterized but may include a shift from glycolysis to mitochondrial respiration. If this phenotype is found in clinical hormone-resistant breast cancers, conventional cytotoxic therapy may be a preferred option for treatment.

  9. Interference with Activator Protein-2 transcription factors leads to induction of apoptosis and an increase in chemo- and radiation- sensitivity in breast cancer cells

    LENUS (Irish Health Repository)

    Thewes, Verena

    2010-05-11

    Abstract Background Activator Protein-2 (AP-2) transcription factors are critically involved in a variety of fundamental cellular processes such as proliferation, differentiation and apoptosis and have also been implicated in carcinogenesis. Expression of the family members AP-2α and AP-2γ is particularly well documented in malignancies of the female breast. Despite increasing evaluation of single AP-2 isoforms in mammary tumors the functional role of concerted expression of multiple AP-2 isoforms in breast cancer remains to be elucidated. AP-2 proteins can form homo- or heterodimers, and there is growing evidence that the net effect whether a cell will proliferate, undergo apoptosis or differentiate is partly dependent on the balance between different AP-2 isoforms. Methods We simultaneously interfered with all AP-2 isoforms expressed in ErbB-2-positive murine N202.1A breast cancer cells by conditionally over-expressing a dominant-negative AP-2 mutant. Results We show that interference with AP-2 protein function lead to reduced cell number, induced apoptosis and increased chemo- and radiation-sensitivity. Analysis of global gene expression changes upon interference with AP-2 proteins identified 139 modulated genes (90 up-regulated, 49 down-regulated) compared with control cells. Gene Ontology (GO) investigations for these genes revealed Cell Death and Cell Adhesion and Migration as the main functional categories including 25 and 12 genes, respectively. By using information obtained from Ingenuity Pathway Analysis Systems we were able to present proven or potential connections between AP-2 regulated genes involved in cell death and response to chemo- and radiation therapy, (i.e. Ctgf, Nrp1, Tnfaip3, Gsta3) and AP-2 and other main apoptosis players and to create a unique network. Conclusions Expression of AP-2 transcription factors in breast cancer cells supports proliferation and contributes to chemo- and radiation-resistance of tumor cells by impairing the

  10. Piperine, a piperidine alkaloid from Piper nigrum re-sensitizes P-gp, MRP1 and BCRP dependent multidrug resistant cancer cells.

    Science.gov (United States)

    Li, Sen; Lei, Yu; Jia, Yingjie; Li, Na; Wink, Michael; Ma, Yonggang

    2011-12-15

    Over-expression of P-gp, MRP1 and BCRP in tumor cells is one of the important mechanisms leading to multidrug resistance (MDR), which impairs the efficacy of chemotherapy. P-gp, MRP1 and BCRP are ABC (ATP-Binding Cassette) transporters, which can expel a variety of lipophilic anti-cancer drugs and protect tumor cells. During a screening of MDR reversal agents among alkaloids of various structural types, a piperidine alkaloid, piperine (a main piperidine alkaloid in Piper nigurm) was identified as an inhibitor. Piperine can potentiate the cytotoxicity of anti-cancer drugs in resistant sublines, such as MCF-7/DOX and A-549/DDP, which were derived from MCF-7 and A-549 cell lines. At a concentration of 50 μM piperine could reverse the resistance to doxorubicin 32.16 and 14.14 folds, respectively. It also re-sensitized cells to mitoxantrone 6.98 folds. In addition, long-term treatment of cells by piperine inhibits transcription of the corresponding ABC transporter genes. These results suggest that piperine can reverse MDR by multiple mechanisms and it may be a promising lead compound for future studies.

  11. Noscapine Increases the Sensitivity of Drug-Resistant Ovarian Cancer Cell Line SKOV3/DDP to Cisplatin by Regulating Cell Cycle and Activating Apoptotic Pathways.

    Science.gov (United States)

    Shen, Wei; Liang, Bingfeng; Yin, Jie; Li, Xiurong; Cheng, Jianxin

    2015-05-01

    Cisplatin is a first-line chemotherapy drug against ovarian cancer. However, its strong toxic side effects and the development of cisplatin resistance in human cancer cells seriously influence the effects of chemotherapy and quality of life in patients. Noscapine (Nos), a non-toxic benzylisoquinoline alkaloid extracted from opium, has been recently reported to have anti-cancer activity, but the mechanism of that effect has not been clearly established. In the present study, we investigated cytotoxicity of Nos in combination with cisplatin (DDP) in drug-resistant human ovarian cancer cell line SKOV3/DDP in vitro and in vivo null mice xenograft model. Cell proliferation was measured by MTT assay, flow cytometry was used to analyze cell cycle and apoptosis, protein expression of several apoptotic factors was investigated by flow cytometry and immunohistochemical method, and their mRNA expression levels were determined by real-time PCR. In vitro experiments showed that Nos significantly inhibited proliferation of SKOV3/DDP cells. DDP/Nos-combined treatment notably enhanced DDP-induced inhibition of cell proliferation and increased the pro-apoptotic effect of DDP in SKOV3/DDP cells. DDP/Nos administration increased the proportion of G2/M cells, reduced both protein and mRNA expression of anti-apoptotic factors XIAP, surviving and NF-kB, and augmented protein and mRNA levels of pro-apoptotic caspase-3. In vivo experiments revealed that Nos/DDP treatment increased the apoptotic rate of xenograft tumors in null mice. Tumor volume decreased from 1.733 ± 0.155 g in mice treated with DDP alone to 1.191 ± 0.106 g in animals treated with Nos/DDP. These observations suggest that Nos increases the anti-cancer activity of DDP against the drug-resistant ovarian cancer cell line SKOV3/DDP by modulating the cell cycle and activating apoptotic pathways. The study provides a new chemotherapy strategy for the treatment of DDP-resistant human ovarian cancer.

  12. Targeting the DNA replication checkpoint by pharmacologic inhibition of Chk1 kinase: a strategy to sensitize APC mutant colon cancer cells to 5-fluorouracil chemotherapy.

    Science.gov (United States)

    Martino-Echarri, Estefania; Henderson, Beric R; Brocardo, Mariana G

    2014-10-30

    5-fluorouracil (5-FU) is the first line component used in colorectal cancer (CRC) therapy however even in combination with other chemotherapeutic drugs recurrence is common. Mutations of the adenomatous polyposis coli (APC) gene are considered as the initiating step of transformation in familial and sporadic CRCs. We have previously shown that APC regulates the cellular response to DNA replication stress and recently hypothesized that APC mutations might therefore influence 5-FU resistance. To test this, we compared CRC cell lines and show that those expressing truncated APC exhibit a limited response to 5-FU and arrest in G1/S-phase without undergoing lethal damage, unlike cells expressing wild-type APC. In SW480 APC-mutant CRC cells, 5-FU-dependent apoptosis was restored after transient expression of full length APC, indicating a direct link between APC and drug response. Furthermore, we could increase sensitivity of APC truncated cells to 5-FU by inactivating the Chk1 kinase using drug treatment or siRNA-mediated knockdown. Our findings identify mutant APC as a potential tumor biomarker of resistance to 5-FU, and importantly we show that APC-mutant CRC cells can be made more sensitive to 5-FU by use of Chk1 inhibitors.

  13. Guizhi Fuling Wan, a Traditional Chinese Herbal Formula, Sensitizes Cisplatin-Resistant Human Ovarian Cancer Cells through Inactivation of the PI3K/AKT/mTOR Pathway

    Directory of Open Access Journals (Sweden)

    Li Han

    2016-01-01

    Full Text Available The aim of the study was to explore the possible mechanisms that Guizhi Fuling Wan (GFW enhances the sensitivity of the SKOV3/DDP ovarian cancer cells and the resistant xenograft tumours to cisplatin. Rat medicated sera containing GFW were prepared by administering GFW to rats, and the primary bioactive constituents of the sera were gallic acid, paeonol, and paeoniflorin analysed by HPLC/QqQ MS. Cell counting kit-8 analysis was shown that coincubation of the sera with cisplatin/paclitaxel enhanced significantly the cytotoxic effect of cisplatin or paclitaxel in SKOV3/DDP cells. The presence of the rat medicated sera containing GFW resulted in an increase in rhodamine 123 accumulation by flow cytometric assays and a decrease in the protein levels of P-gp, phosphorylation of AKT at Ser473, and mTOR in a dose-dependent manner in SKOV3/DDP cells by western blot analysis, but the sera had no effect on the protein levels of PI3K p110α and total AKT. The low dose of GFW enhanced the anticancer efficacy of cisplatin and paclitaxel treatment in resistant SKOV3/DDP xenograft tumours. GFW could sensitize cisplatin-resistant SKOV3/DDP cells by inhibiting the protein level and function of P-gp, which may be medicated through inactivation of the PI3K/AKT/mTOR pathway.

  14. The immunomodulatory drug lenalidomide restores a vitamin D sensitive phenotype to the vitamin D resistant breast cancer cell line MDA-MB-231 through inhibition of BCL-2: potential for breast cancer therapeutics.

    Science.gov (United States)

    Brosseau, Carole; Colston, Kay; Dalgleish, Angus George; Galustian, Christine

    2012-02-01

    1α,25-Dihydroxyvitamin D3, (1,25-D3) the biologically active form of vitamin-D, is well established as a cancer cell growth inhibitor in addition to maintaining bone mineralization. In breast cancer cells, inhibitory effects on angiogenesis, and metastasis have been observed together with enhancement of apoptosis and induction of cell cycle arrest. There is a correlation between vitamin-D receptor expression on breast cancer cells and patient survival. However vitamin-D resistance and hypercalcaemia are key limiting factors in clinical use. The IMiD(®) immunomodulatory drug lenalidomide, (Revlimid(®), CC-5013) used in myeloma, can also modulate apoptotic and growth signalling. We studied whether lenalidomide treated breast cancer cells would acquire sensitivity to 1,25-D3 with resulting growth inhibition. The cell lines MCF-12A, MCF-7 and MDA-MB-231, representing non-tumorogenic, tumorogenic, and vitamin-D resistant lines respectively were treated with lenalidomide and/or 1,25-D3(at 100 nM). Whereas lenalidomide alone had no effect on cell growth, a 50% inhibition of cell growth by 1,25-D3 was achieved with additional 1 μM lenalidomide in resistant cells. This effect was through apoptosis measured by PARP cleavage and annexin-V expression. An apoptosis protein array showed that the 1,25-D3 and lenalidomide combination increased pro-apoptotic proteins (phosphorylated p53) and decreased BCL-2 expression. BCL-2 inhibition is proposed as a mechanism of action for the combined drugs in the MDA-MB-231 cell line. In vitamin D resistant cell lines MCF-7VDR and HBL-100 where the combination does not affect BCL-2-no inhibitory effect is observed. These results demonstrate the potential for the combinatorial use of lenalidomide and 1,25-D3 for vitamin D refractory tumours.

  15. Cell phones and cancer

    Science.gov (United States)

    Cancer and cell phones; Do cell phones cause cancer? ... Several major studies show no link between cell phones and cancer at this time. However, since the information available is based on short-term studies, the impact of many years of ...

  16. Lung Cancer Stem Cells

    Directory of Open Access Journals (Sweden)

    Sharon R. Pine

    2008-01-01

    Full Text Available Lung cancer remains a major cause of cancer-related lethality because of high incidence and recurrence in spite of significant advances in staging and therapies. Recent data indicates that stem cells situated throughout the airways may initiate cancer formation. These putative stem cells maintain protumorigenic characteristics including high proliferative capacity, multipotent differentiation, drug resistance and long lifespan relative to other cells. Stem cell signaling and differentiation pathways are maintained within distinct cancer types, and destabilization of this machinery may participate in maintenance of cancer stem cells. Characterization of lung cancer stem cells is an area of active research and is critical for developing novel therapies. This review summarizes the current knowledge on stem cell signaling pathways and cell markers used to identify the lung cancer stem cells.

  17. Difference in Expression of Bcl-2 and Bcl-xl Genes in Cisplatin- sensitive and Cisplatin-resistant Human in Ovarian Cancer Cell Lines

    Institute of Scientific and Technical Information of China (English)

    于利利; 王泽华

    2004-01-01

    To investigate the expression of Bcl-2 and Bcl-xl gene in sensitive (A2780) and drug-resistance (AD6) human ovarian cancer cell lines and explore the molecular mechanism of multidrug resistance, A2780 and AD6 were detected by using DNA gel electrophoresis, flow cytometry and RT-PCR. Our results showed that (1)"DNA ladder" was observed in A2780 and AD6 after cisplatin treatment; (2) after 3.0, 6.0, 9.9 μg/ml of cisplatin treatment, a significant difference was noted in the rate of apoptosis between in A2780 and AD6 (P<0.05); (3) Bcl-2 and Bcl-xl genes were overexpressed in AD6. After cisplatin treatment, the expression of Bcl-2 and Bcl-xl genes was down-regulated in A2780 and AD6. It is concluded that cisplatin could induce the apoptosis of ovarian cancer cells, and the over-expression of Bcl-2 and Bcl-xl genes may contribute to apoptotic inhibition and the development of multidrug-resistance of human ovarian cancer.

  18. BMX acts downstream of PI3K to promote colorectal cancer cell survival and pathway inhibition sensitizes to the BH3 mimetic ABT-737.

    Science.gov (United States)

    Potter, Danielle S; Kelly, Paul; Denneny, Olive; Juvin, Veronique; Stephens, Len R; Dive, Caroline; Morrow, Christopher J

    2014-02-01

    Evasion of apoptosis is a hallmark of cancer, and reversing this process by inhibition of survival signaling pathways is a potential therapeutic strategy. Phosphoinositide 3-kinase (PI3K) signaling can promote cell survival and is upregulated in solid tumor types, including colorectal cancer (CRC), although these effects are context dependent. The role of PI3K in tumorigenesis combined with their amenability to specific inhibition makes them attractive drug targets. However, we observed that inhibition of PI3K in HCT116, DLD-1, and SW620 CRC cells did not induce apoptotic cell death. Moreover, these cells were relatively resistant to the Bcl-2 homology domain 3 (BH3) mimetic ABT-737, which directly targets the Bcl-2 family of apoptosis regulators. To test the hypothesis that PI3K inhibition lowers the apoptotic threshold without causing apoptosis per se, PI3K inhibitors were combined with ABT-737. PI3K inhibition enhanced ABT-737-induced apoptosis by 2.3- to 4.5-fold and reduced expression levels of MCL-1, the resistance biomarker for ABT-737. PI3K inhibition enhanced ABT-737-induced apoptosis a further 1.4- to 2.4-fold in CRC cells with small interfering RNA-depleted MCL-1, indicative of additional sensitizing mechanisms. The observation that ABT-737-induced apoptosis was unaffected by inhibition of PI3K downstream effectors AKT and mTOR, implicated a novel PI3K-dependant pathway. To elucidate this, an RNA interference (RNAi) screen of potential downstream effectors of PI3K signaling was conducted, which demonstrated that knockdown of the TEC kinase BMX sensitized to ABT-737. This suggests that BMX is an antiapoptotic downstream effector of PI3K, independent of AKT.

  19. BMX Acts Downstream of PI3K to Promote Colorectal Cancer Cell Survival and Pathway Inhibition Sensitizes to the BH3 Mimetic ABT-737

    Directory of Open Access Journals (Sweden)

    Danielle S. Potter

    2014-02-01

    Full Text Available Evasion of apoptosis is a hallmark of cancer, and reversing this process by inhibition of survival signaling pathways is a potential therapeutic strategy. Phosphoinositide 3-kinase (PI3K signaling can promote cell survival and is upregulated in solid tumor types, including colorectal cancer (CRC, although these effects are context dependent. The role of PI3K in tumorigenesis combined with their amenability to specific inhibition makes them attractive drug targets. However, we observed that inhibition of PI3K in HCT116, DLD-1, and SW620 CRC cells did not induce apoptotic cell death. Moreover, these cells were relatively resistant to the Bcl-2 homology domain 3 (BH3 mimetic ABT-737, which directly targets the Bcl-2 family of apoptosis regulators. To test the hypothesis that PI3K inhibition lowers the apoptotic threshold without causing apoptosis per se, PI3K inhibitors were combined with ABT-737. PI3K inhibition enhanced ABT-737-induced apoptosis by 2.3- to 4.5-fold and reduced expression levels of MCL-1, the resistance biomarker for ABT-737. PI3K inhibition enhanced ABT-737-induced apoptosis a further 1.4- to 2.4-fold in CRC cells with small interfering RNA-depleted MCL-1, indicative of additional sensitizing mechanisms. The observation that ABT-737-induced apoptosis was unaffected by inhibition of PI3K downstream effectors AKT and mTOR, implicated a novel PI3K-dependant pathway. To elucidate this, an RNA interference (RNAi screen of potential downstream effectors of PI3K signaling was conducted, which demonstrated that knockdown of the TEC kinase BMX sensitized to ABT-737. This suggests that BMX is an antiapoptotic downstream effector of PI3K, independent of AKT.

  20. Cinnamaldehyde Derivative (CB-PIC Sensitizes Chemo-Resistant Cancer Cells to Drug-Induced Apoptosis via Suppression of MDR1 and its Upstream STAT3 and AKT Signalling

    Directory of Open Access Journals (Sweden)

    Jianzhong Xi

    2015-03-01

    Full Text Available Background/Aims: Our group reported that cinnamaldehyde derivative, (E-4-((2-(3-oxopop-1-enylphenoxymethylpyridinium malonic acid (CB-PIC induced apoptosis in hypoxic SW620 colorectal cancer cells via activation of AMP-activated protein kinase (AMPK and extracellular signal regulated kinase (ERK. Herein, sensitizing effect of CB-PIC was investigated in resistant cancer cells such as paclitaxel (PT resistant lung cancer cells (H460/PT, and Adriamycin (Adr resistant breast cancer (MCF7/Adr and colon cancer (HCT15/cos cells. Methods: Various drug resistant cell lines were treated with CB-PIC, and the signalling pathway and functional assay were explored by Western blot, Rhodamine assay, FACS, RT-PCR and MTT assay. Results: We found that CB-PIC effectively exerted cytotoxicity, increased sub G1 population and the cleaved form of poly (ADP-ribose polymerase (PARP and caspase 9 in drug resistant cancer cells. Furthermore, CB-PIC sensitized resistant cancer cells to adriamycin via downregulation of survival proteins such as survivin, Bcl-xL and Bcl-2, along with MDR1 suppression leading to accumulation of drug in the intracellular region. Of note, CB-PIC transcriptionally decreased MDR1 expression via suppression of STAT3 and AKT signalling in three resistant cancer cells with highly expressed P-glycoprotein. Nonetheless, CB-PIC did not affect transport activity of P-glycoprotein in a short time efflux assay, while epigallocatechin gallate (EGCG accumulated Rhodamine 123 into intracellular region of cell by direct inhibition of MDR1 transport activity. Conclusions: These data demonstrate that CB-PIC suppresses the P-glycoprotein expression through inhibition of STAT3 and AKT signalling to overcome drug resistance in chemo-resistant cancer cells as a potent chemotherapeutic sensitizer.

  1. MicroRNA-133b targets glutathione S-transferase π expression to increase ovarian cancer cell sensitivity to chemotherapy drugs

    Directory of Open Access Journals (Sweden)

    Chen S

    2015-09-01

    Full Text Available Shuo Chen,1 Jin-Wen Jiao,2 Kai-Xuan Sun,1 Zhi-Hong Zong,3 Yang Zhao1 1Department of Gynecology, The First Affiliated Hospital of China Medical University, Shenyang, People’s Republic of China; 2Department of Gynecology, The Affiliated Hospital of Medical College, Qingdao University, Qingdao, People’s Republic of China; 3Department of Biochemistry and Molecular Biology, College of Basic Medicine, China Medical University, Shenyang, People’s Republic of China Background: Accumulating studies reveal that aberrant microRNA (miRNA expression can affect the development of chemotherapy drug resistance by modulating the expression of relevant target proteins. The aim of this study was to investigate the role of miR-133b in the development of drug resistance in ovarian cancer cells. Methods: We examined the levels of miR-133b expression in ovarian carcinoma tissues and the human ovarian carcinoma cell lines (A2780, A2780/DDP and A2780/Taxol, respectively. We determined the cell viability of these cell lines treated with cisplatin or paclitaxel in the presence or absence of miR-133b or anti-miR-133b transfection using the MTT assay. Reverse transcription polymerase chain reaction and Western blotting were used to assess the mRNA and protein expression levels of two drug-resistance-related genes: glutathione S-transferase (GST-π and multidrug resistance protein 1 (MDR1. The dual-luciferase reporter assay was used to detect the promoter activity of GST-π in the presence and absence of miR-133b. Results: The expression of miR-133b was significantly lower in primary resistant ovarian carcinomas than in the chemotherapy-sensitive carcinomas (P<0.05, and the same results were found in primary resistant ovarian cell lines (A2780/Taxol and A2780/DDP compared to the chemotherapy-sensitive cell line (A2780; P<0.05. Following miR-133b transfection, four cell lines showed increased sensitivity to paclitaxel and cisplatin, while anti-miR-133b transfection

  2. Protolichesterinic acid, isolated from the lichen Cetraria islandica, reduces LRRC8A expression and volume-sensitive release of organic osmolytes in human lung epithelial cancer cells

    DEFF Research Database (Denmark)

    Thorsteinsdottir, Unnur Arna; Thorsteinsdottir, Margret; Lambert, Ian Henry

    2016-01-01

    We have tested the effect of protolichesterinic acid (PA) on the activity of the volume-sensitive release pathway for the organic osmolyte taurine (VSOAC) and the expression of the leucine-rich-repeat-channel 8A (LRRC8A) protein, which constitutes an essential VSOAC component. Exposing human lung...... of apoptosis) and p21 (regulator of cell cycle progression), respectively. PA reduces cell viability by 30% but has no effect on p21/Bax expression. This excludes PA as a pro-apoptotic drug in A549 cells....... cancer cells (A549) to PA (20 μg/mL, 24 h) reduces LRRC8A protein expression by 25% and taurine release following osmotic cell swelling (320 → 200 mOsm) by 60%. C75 (20 μg/mL, 24 h), a γ-lactone with a C8 carbon fatty acid chain, reduces VSOAC activity by 30%, i.e. less than PA. Stearic acid (20 μg......, excluding that PA mediated inhibition of VSOAC involves 5-LO inhibition. A549 cells exposed to the chemotherapeutic drug cisplatin (10 μM, 24 h) reveal signs of apoptosis, i.e. 25% reduction in cell viability as well as 1.3-, 1.5- and 3.3-fold increase in the expression of LRRC8A, Bax (regulator...

  3. Inhibition of the Proteasome β2 Site Sensitizes Triple-Negative Breast Cancer Cells to β5 Inhibitors and Suppresses Nrf1 Activation.

    Science.gov (United States)

    Weyburne, Emily S; Wilkins, Owen M; Sha, Zhe; Williams, David A; Pletnev, Alexandre A; de Bruin, Gerjan; Overkleeft, Hermann S; Goldberg, Alfred L; Cole, Michael D; Kisselev, Alexei F

    2017-02-16

    The proteasome inhibitors carfilzomib (Cfz) and bortezomib (Btz) are used successfully to treat multiple myeloma, but have not shown clinical efficacy in solid tumors. Here we show that clinically achievable inhibition of the β5 site of the proteasome by Cfz and Btz does not result in loss of viability of triple-negative breast cancer cell lines. We use site-specific inhibitors and CRISPR-mediated genetic inactivation of β1 and β2 to demonstrate that inhibiting a second site of the proteasome, particularly the β2 site, sensitizes cell lines to Btz and Cfz in vitro and in vivo. Inhibiting both β5 and β2 suppresses production of the soluble, active form of the transcription factor Nrf1 and prevents the recovery of proteasome activity through induction of new proteasomes. These findings provide a strong rationale for the development of dual β5 and β2 inhibitors for the treatment of solid tumors.

  4. MicroRNA-149 Increases the Sensitivity of Colorectal Cancer Cells to 5-Fluorouracil by Targeting Forkhead Box Transcription Factor FOXM1

    Directory of Open Access Journals (Sweden)

    Xiaobei Liu

    2016-07-01

    Full Text Available Background/Aims: Previously, we have shown that microRNA (miR-149 suppresses the migration and invasion of colorectal cancer (CRC cells by targeting forkhead box transcription factor (FOXM1. However, the roles of miR-149 in the chemoresistance of CRC cells to 5-Fluorouracil (5-FU is unclear. The aim of this study is to investigate whether miR-149 targets FOXM1 to regulate the 5-FU resistance of CRC. Methods: The qRT-PCR assay was performed to detect the expression of miR-149 in 5-FU-resistant CRC cells (HCT-8/5-FU and LoVo/5-FU and their parental CRC cells (HCT-8 and LoVo. Also, the effects of miR-149 expression on the sensitivity of CRC cells to 5-FU were determined by gain- and loss-of-function assays. Finally, whether miR-149 regulates the 5-FU resistance of CRC cells by targeting the mammalian Forkhead Box M1 (FOXM1 was investigated. Results: The expression of miR-149 was significantly downregulated in 5-FU-resistant CRC cells in comparison with their parental CRC cells. Re-expression of miR-149 could enhance the 5-FU sensitivity of 5-FU-resistant CRC cells by increasing 5-FU-inducing apoptosis, while downregulation of miR-149 could decrease the 5-FU sensitivity of parental CRC cells by decreasing 5-FU-inducing apoptosis. In addition, the luciferase assay indicated that miR-149 could bind to the 3'-UTR sequence of FOXM1 mRNA. The silencing of FOXM1 could mimic the effect of miR-149 upregulation on the 5-FU resistance of 5-FU-resistant CRC cells. Furthermore, the expression of miR-149 in the 5-FU-responding CRC tissues was significantly higher than that in the non-responding tissues and inversely correlated with FOXM1 mRNA level. Conclusions: MiR-149 reverses the resistance of CRC cells to 5-FU by directly targeting FOXM1. Thus, targeting miR-149/FOXM1 signaling will be a potential strategy in the treatment of 5-FU-chemoresistant CRC.

  5. High-Density and Very-Low-Density Lipoprotein Have Opposing Roles in Regulating Tumor-Initiating Cells and Sensitivity to Radiation in Inflammatory Breast Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Wolfe, Adam R. [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Morgan Welch Inflammatory Breast Cancer Research Program and Clinic, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Atkinson, Rachel L. [Morgan Welch Inflammatory Breast Cancer Research Program and Clinic, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Reddy, Jay P. [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Debeb, Bisrat G.; Larson, Richard; Li, Li [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Department of Clinical Cancer Prevention, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Masuda, Hiroko; Brewer, Takae [Department of Clinical Cancer Prevention, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Atkinson, Bradley J. [Department of Clinical Pharmacy Services, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Brewster, Abeena [Morgan Welch Inflammatory Breast Cancer Research Program and Clinic, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Ueno, Naoto T. [Department of Clinical Cancer Prevention, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Woodward, Wendy A., E-mail: wwoodward@mdanderson.org [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Department of Clinical Cancer Prevention, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)

    2015-04-01

    Purpose: We previously demonstrated that cholesterol-lowering agents regulate radiation sensitivity of inflammatory breast cancer (IBC) cell lines in vitro and are associated with less radiation resistance among IBC patients who undergo postmastectomy radiation. We hypothesized that decreasing IBC cellular cholesterol induced by treatment with lipoproteins would increase radiation sensitivity. Here, we examined the impact of specific transporters of cholesterol (ie lipoproteins) on the responses of IBC cells to self-renewal and to radiation in vitro and on clinical outcomes in IBC patients. Methods and Materials: Two patient-derived IBC cell lines, SUM 149 and KPL4, were incubated with low-density lipoproteins (LDL), very-low-density lipoproteins (VLDL), or high-density lipoproteins (HDL) for 24 hours prior to irradiation (0-6 Gy) and mammosphere formation assay. Cholesterol panels were examined in a cohort of patients with primary IBC diagnosed between 1995 and 2011 at MD Anderson Cancer Center. Lipoprotein levels were then correlated to patient outcome, using the log rank statistical model, and examined in multivariate analysis using Cox regression. Results: VLDL increased and HDL decreased mammosphere formation compared to untreated SUM 149 and KPL4 cells. Survival curves showed enhancement of survival in both of the IBC cell lines when pretreated with VLDL and, conversely, radiation sensitization in all cell lines when pretreated with HDL. In IBC patients, higher VLDL values (>30 mg/dL) predicted a lower 5-year overall survival rate than normal values (hazard ratio [HR] = 1.9 [95% confidence interval [CI]: 1.05-3.45], P=.035). Lower-than-normal patient HDL values (<60 mg/dL) predicted a lower 5-year overall survival rate than values higher than 60 mg/dL (HR = 3.21 [95% CI: 1.25-8.27], P=.015). Conclusions: This study discovered a relationship among the plasma levels of lipoproteins, overall patient response, and radiation resistance in IBC patients

  6. Radiation induced chemotherapy sensitization in trimodality therapy of stage 3 non small cell lung cancer. A preliminary report

    Energy Technology Data Exchange (ETDEWEB)

    Takita, H. [Millard Fillmore Hospital, Buffalo (United States); Shin, K. H. [CCS Oncology Center, Kenmore, NY, (United States)

    2000-12-01

    The overall cure rate of locally advanced non-small cell lung carcinoma (NSCLC) remains poor. Although there have been encouraging reports of preoperative use of chemotherapy, more recent trend is the trimodal approach of radiation, chemo, and surgical-therapies. With the trimodal therapy, increased tumor response and resectability are reported, however, there are increased treatment related side effects. It was observed that a relatively small dose of radiation given prior to induction chemotherapy greatly enhanced the tumor response to the chemotherapy without increased toxicity. A total of 18 patients (8 3. A and 10 3.B) were initially given 20 Gy of radiation therapy in 10 fractions and then received 2 courses of Taxol combination chemotherapy. The overall response rate was 83% (15/18) and 13 out of 18 patients underwent surgery. There was one postoperative death (not therapy related). It is speculated that the small dose of radiation therapy may have sensitized the tumor to subsequent chemotherapy, and it was suggested a new hypothesis of radiation therapy induced chemotherapy sensitization.

  7. Correlation of thymidylate synthase, thymidine phosphorylase and dihydropyrimidine dehydrogenase with sensitivity of gastrointestinal cancer cells to 5-fluorouracil and 5-fluoro-2'-deoxyuridine

    Institute of Scientific and Technical Information of China (English)

    Tao Ma; Zheng-Gang Zhu; Yu-Bao Ji; Yi Zhang; Ying-Yan Yu; Bing-Ya Liu; Hao-Ran Yin; Yan-Zhen Lin

    2004-01-01

    AIM: To determine the expression levels of three metabolic enzymes of fluoropyrimidines: thymidylate synthase (TS),thymidine phosphorylase (TP) and dihydropyrimidine dehydrogenase (DPD) in seven human gastrointestinal cancer cell lines, and to compare the enzyme levels with the sensitivity to 5-fluorouracil (5-FU) and 5-fluoro-2'-deoxyuridine (FdUrd).METHODS: TS, TP and DPD mRNA levels were assessed by semi-quantitative RT-PCR, TP and DPD protein contents were measured by ELISA. Fifty percent inhibitory concentrations of growth (IC50), representing the sensitivityto drugs, were determined by MTT assay.RESULTS: IC50 values ranged from 1.28 to 12.26 uM for 5-FU, and from 5.02 to 24.21 uM for FdUrd, respectively.Cell lines with lower DPD mRNA and protein levels tended to be more sensitive to 5-FU (P<0.05), but neither TS nor TP correlated with 5-FU IC50 (P>0.05). Only TS mRNA level was sharply related with FdUrd sensitivity (P<0.05), but TP and DPD were not (P>0.05). A correlation was found between mRNA and protein levels of DPD (P<0.05), but not TP (P<0.05).CONCLUSION: DPD and TS enzyme levels may be useful indicators in predicting the antitumor activity of 5-FU or FdUrd, respectively.

  8. Suppression of casein kinase 2 sensitizes tumor cells to antitumor TRAIL therapy by regulating the phosphorylation and localization of p65 in prostate cancer.

    Science.gov (United States)

    Gang, Xiaokun; Wang, Yao; Wang, Yingdi; Zhao, Yu; Ding, Liya; Zhao, Jingwen; Sun, Lin; Wang, Guixia

    2015-09-01

    In the United States, prostate cancer (PCa) is the most commonly diagnosed cancer in males. For PCa at the late hormone-refractory stage, substantial improvement in treatment strategies is critically needed. TNF-related apoptosis-inducing ligand (TRAIL) is a promising anticancer agent, but both intrinsic and acquired resistance to TRAIL poses a huge problem in establishing clinically effective TRAIL therapies. In the present study, we examined the role played by casein kinase 2 (CK2) in the TRAIL‑induced nuclear factor κ-light-chain-enhancer of activated B cell (NF-κB) pathway in a PCa cell line. Downregulation of CK2 combined with a sub-dose of TRAIL suppressed p65 phosphorylation at serine 536. The combination treatment of TRAIL and the CK2 inhibitor decreased p65 nuclear translocation. Under the treatment of a sub-dose of TRAIL, downregulation of CK2, using both genetic and pharmacological approaches, decreased the transcriptional activity of NF-κB and the expression of NF-κB downstream anti-apoptosis genes. Therefore, we provided novel molecular mechanistic insight reporting that CK2 regulates the sensitivity of PCa cells to the antitumor effect of TRAIL. This is important for understanding how the TRAIL pathway is disrupted in PCa and may help to develop an effective combinatorial therapy for PCa.

  9. Latent membrane protein 1 of Epstein-Barr virus sensitizes cancer cells to cisplatin by enhancing NF-κB p50 homodimer formation and downregulating NAPA expression.

    Science.gov (United States)

    Wu, Zchong-Zcho; Chow, Kai-Ping N; Kuo, Tzu-Ching; Chang, Yu-Sun; Chao, Chuck C-K

    2011-12-15

    Expression of the oncogenic latent membrane protein 1 (LMP1) of Epstein-Barr virus is involved in the pathogenesis of nasopharyngeal carcinoma (NPC) and lymphoma. In previous studies, we found that expression of LMP1 was sufficient to transform BALB/c-3T3 cells. In contrast, other studies have shown that LMP1 induces apoptosis in a NF-κB-dependent manner and also inhibits the growth of tumors in mice, thereby indicating that LMP1 may produce various biological effects depending on the biological and cellular context. Still, the mechanism underlying the pro-apoptotic activity of LMP1 remains unclear. In the present study, we found that LMP1 inhibits the expression of NAPA, an endoplasmic reticulum SNARE protein that possesses anti-apoptotic properties against the DNA-damaging drug cisplatin. Accordingly, LMP1-transformed BALB/c-3T3 cells were sensitized to cisplatin-induced apoptosis, whereas no sensitization effect was noted following treatment with the mitotic spindle-damaging drugs vincristine and taxol. Knockdown of LMP1 with antisense oligonucleotides restored NAPA protein level and rendered the cells resistant to cisplatin. Similarly, overexpression of NAPA reduced the effect of LMP1 and induced resistance to cisplatin. LMP1 was shown to upregulate the NF-κB subunit p50, leading to formation of p50 homodimers on the NAPA promoter. These findings suggest that the viral protein LMP1 may sensitize cancer cells to cisplatin chemotherapy by downregulating NAPA and by enhancing the formation of p50 homodimers which in turn inhibit the expression of NF-κB regulated anti-apoptotic genes. These findings provide an explanatory mechanism for the pro-apoptotic activity of LMP1 as well as new therapeutic targets to control tumor growth.

  10. Protein tyrosine phosphatase SHP-1 sensitizes EGFR/HER-2 positive breast cancer cells to trastuzumab through modulating phosphorylation of EGFR and HER-2

    Directory of Open Access Journals (Sweden)

    Wu YF

    2015-09-01

    on tumorigenicity and trastuzumab sensitivity were confirmed via in vivo xenograft model.Results: Trastuzumab-resistant SKBr-3 cells showed aberrant co-expression of EGFR and HER-2. Introduction of wild-type SHP-1 inhibited cell proliferation, clone formation, and promoted the apoptosis induced by trastuzumab. Meanwhile, SHP-1 overexpression reduced phosphorylation levels of EGFR and HER-2 both in parental and trastuzumab-resistant SKBr-3 cells. In vivo study showed an increased antitumor effect of trastuzumab in SHP-1 overexpressed xenografts. At last, we discovered that SHP-1 can make complexes with both EGFR and HER-2, and both phospho-EGFR and phosphor-HER-2 levels in wild-type SHP-1 immunoprecipitates were less than those in phosphatase-inactive SHP-1 (C453S immunoprecipitates, indicating that EGFR and HER-2 are potential substrates of SHP-1.Conclusion: Taken together, we have demonstrated that the SHP-1 is a negative regulatory factor of the tyrosine kinase activity of HER-2 and EGFR through inhibiting phosphorylation. Dual targeting of EGFR and HER-2, by combining trastuzumab with SHP-1 overexpression, may improve response in HER-2 overexpressing breast cancer cells that also express high levels of EGFR. Keywords: breast cancer, trastuzumab, EGFR, HER-2, SHP-1, drug resistance 

  11. Anthelminthic drug niclosamide sensitizes the responsiveness of cervical cancer cells to paclitaxel via oxidative stress-mediated mTOR inhibition.

    Science.gov (United States)

    Chen, Liping; Wang, Li; Shen, Haibin; Lin, Hui; Li, Dan

    2017-03-04

    Drug repurposing represents an alternative therapeutic strategy to cancer treatment. The potent anti-cancer activities of a FDA-approved anthelminthic drug niclosamide have been demonstrated in various cancers. However, whether niclosamide is active against cervical cancer is unknown. In this study, we investigated the effects of niclosamide alone and its combination with paclitaxel in cervical cancer in vitro and in vivo. We found that niclosamide significantly inhibited proliferation and induced apoptosis of a panel of cervical cancer cell lines, regardless of their cellular origin and genetic pattern. Niclosamide also inhibited tumor growth in cervical cancer xenograft mouse model. Importantly, niclosamide significantly enhanced the responsiveness of cervical cancer cell to paclitaxel. We further found that niclosamide induced mitochondrial dysfunctions via inhibiting mitochondrial respiration, complex I activity and ATP generation, which led to oxidative stress. ROS scavenge agent N-acetyl-l-cysteine (NAC) completely reversed the effects of niclosamide in increasing cellular ROS, inhibiting proliferation and inducing apoptosis, suggesting that oxidative stress induction is the mechanism of action of niclosamide in cervical cancer cells. In addition, niclosamide significantly inhibited mammalian target of rapamycin (mTOR) signaling pathway in cervical cancer cells and its inhibitory effect on mTOR is modulated by oxidative stress. Our work suggests that niclosamide is a useful addition to the treatment armamentarium for cervical cancer and induction of oxidative stress may be a potential therapeutic strategy in cervical cancer.

  12. Depletion of pro-oncogenic RUNX2 enhances gemcitabine (GEM) sensitivity of p53-mutated pancreatic cancer Panc-1 cells through the induction of pro-apoptotic TAp63.

    Science.gov (United States)

    Ozaki, Toshinori; Nakamura, Mizuyo; Ogata, Takehiro; Sang, Meijie; Yoda, Hiroyuki; Hiraoka, Kiriko; Sang, Meixiang; Shimozato, Osamu

    2016-11-01

    Recently, we have described that siRNA-mediated silencing of runt-related transcription factor 2 (RUNX2) improves anti-cancer drug gemcitabine (GEM) sensitivity of p53-deficient human pancreatic cancer AsPC-1 cells through the augmentation of p53 family TAp63-dependent cell death pathway. In this manuscript, we have extended our study to p53-mutated human pancreatic cancer Panc-1 cells. According to our present results, knockdown of mutant p53 alone had a marginal effect on GEM-mediated cell death of Panc-1 cells. We then sought to deplete RUNX2 using siRNA in Panc-1 cells and examined its effect on GEM sensitivity. Under our experimental conditions, RUNX2 knockdown caused a significant enhancement of GEM sensitivity of Panc-1 cells. Notably, GEM-mediated induction of TAp63 but not of TAp73 was further stimulated in RUNX2-depleted Panc-1 cells, indicating that, like AsPC-1 cells, TAp63 might play a pivotal role in the regulation of GEM sensitivity of Panc-1 cells. Consistent with this notion, forced expression of TAp63α in Panc-1 cells promoted cell cycle arrest and/or cell death, and massively increased luciferase activities driven by TAp63-target gene promoters such as p21WAF1 and NOXA. In addition, immunoprecipitation experiments indicated that RUNX2 forms a complex with TAp63 in Panc-1 cells. Taken together, our current observations strongly suggest that depletion of RUNX2 enhances the cytotoxic effect of GEM on p53-mutated Panc-1 cells through the stimulation of TAp63-dependent cell death pathway even in the presence of a large amount of pro-oncogenic mutant p53, and might provide an attractive strategy to treat pancreatic cancer patients with p53 mutations.

  13. Dye Sensitized Tandem Photovoltaic Cells

    Energy Technology Data Exchange (ETDEWEB)

    Barber, Greg D.

    2009-12-21

    This work provided a new way to look at photoelectrochemical cells and their performance. Although thought of as low efficiency, a the internal efficiency of a 9% global efficiency dye sensitized solar cell is approximately equal to an 18% efficient silicon cell when each is compared to their useful spectral range. Other work undertaken with this contract also reported the first growth oriented titania and perovskite columns on a transparent conducting oxide. Other work has shown than significant performance enhancement in the performance of dye sensitized solar cells can be obtained through the use of coupling inverse opal photonic crystals to the nanocrystalline dye sensitized solar cell. Lastly, a quick efficient method was developed to bond titanium foils to transparent conducting oxide substrates for anodization.

  14. Stages of Renal Cell Cancer

    Science.gov (United States)

    ... cell cancer is a disease in which malignant (cancer) cells form in tubules of the kidney. Renal cell ... diagnosed, tests are done to find out if cancer cells have spread within the kidney or to other ...

  15. Sodium butyrate sensitizes TRAIL-mediated apoptosis by induction of transcription from the DR5 gene promoter through Sp1 sites in colon cancer cells.

    Science.gov (United States)

    Kim, Young-Ho; Park, Jong-Wook; Lee, Jai-Youl; Kwon, Taeg Kyu

    2004-10-01

    Sodium butyrate, a short-chain fatty acid naturally present in the human colon, is able to induce cell cycle arrest, differentiation and apoptosis in various cancer cells. Sodium butyrate is most probably related to the inhibition of deacetylases leading to hyperacetylation of chromatin components such as histones and non-histone proteins and to alterations in gene expression. In this study, we demonstrate for the first time that sodium butyrate selectively up-regulated DR5 but had no effect on the expression of the other TNF-alpha-related apoptosis-inducing ligand (TRAIL) receptor, DR4. Sodium butyrate-induced expression of DR5 involves the putative Sp1 site within the DR5 promoter region. Using a combination of the electrophoretic mobility shift assay and the luciferase reporter assay, we found that a specific Sp1 site (located at -195 bp relative to the transcription start site) is required for sodium butyrate-mediated activation of the DR5 promoter. When HCT116 cells were incubated with sodium butyrate and TRAIL, enhanced TRAIL-mediated apoptosis was observed. The enhanced apoptosis was measured by fluorescent activated cell sorting analysis, DNA fragmentation, poly (ADP-ribose) polymerase cleavage, down-regulation of XIAP and caspase activity. Taken together, the present studies suggest that sodium butyrate may be an effective sensitizer of TRAIL-induced apoptosis.

  16. CQ synergistically sensitizes human colorectal cancer cells to SN-38/CPT-11 through lysosomal and mitochondrial apoptotic pathway via p53-ROS cross-talk.

    Science.gov (United States)

    Chen, Pinjia; Luo, Xiaoyong; Nie, Peipei; Wu, Baoyan; Xu, Wei; Shi, Xinpeng; Chang, Haocai; Li, Bing; Yu, Xiurong; Zou, Zhengzhi

    2017-03-01

    Autophagy plays a key role in supporting cell survival against chemotherapy-induced apoptosis. In this study, we found the chemotherapy agent SN-38 induced autophagy in colorectal cancer (CRC) cells. However, inhibition of autophagy using a small molecular inhibitor 3-methyladenine (3-MA) and ATG5 siRNA did not increase SN-38-induced cytotoxicity in CRC cells. Notably, another autophagy inhibitor chloroquine (CQ) synergistically enhanced the anti-tumor activity of SN-38 in CRC cells with wild type (WT) p53. Subsequently, we identified a potential mechanism of this cooperative interaction by showing that CQ and SN-38 acted together to trigger reactive oxygen species (ROS) burst, upregulate p53 expression, elicit the loss of lysosomal membrane potential (LMP) and mitochondrial membrane potential (∆ψm). In addition, ROS induced by CQ plus SN-38 upregulated p53 levels by activating p38, conversely, p53 stimulated ROS. These results suggested that ROS and p53 reciprocally promoted each other's production and cooperated to induce CRC cell death. Moreover, we showed induction of ROS and p53 by the two agents provoked the loss of LMP and ∆ψm. Altogether, all results suggested that CQ synergistically sensitized human CRC cells with WT p53 to SN-38 through lysosomal and mitochondrial apoptotic pathway via p53-ROS cross-talk. Lastly, we showed that CQ could enhance CRC cells response to CPT-11 (a prodrug of SN-38) in xenograft models. Thus the combined treatment might represent an attractive therapeutic strategy for the treatment of CRC.

  17. The scaffolding protein NHERF1 sensitizes EGFR-dependent tumor growth, motility and invadopodia function to gefitinib treatment in breast cancer cells.

    Science.gov (United States)

    Bellizzi, Antonia; Greco, Maria Raffaella; Rubino, Rosa; Paradiso, Angelo; Forciniti, Stefania; Zeeberg, Katrine; Cardone, Rosa Angela; Reshkin, Stephan Joel

    2015-03-01

    Triple negative breast cancer (TNBC) patients cannot be treated with endocrine therapy or targeted therapies due to lack of related receptors. These patients overexpress the epidermal growth factor receptor (EGFR), but are resistant to tyrosine kinase inhibitors (TKIs) and anti-EGFR therapies. Mechanisms suggested for resistance to TKIs include EGFR independence, mutations and alterations in EGFR and in its downstream signalling pathways. Ligand-induced endocytosis and degradation of EGFR play important roles in the downregulation of the EGFR signal suggesting that its activity could be regulated by targeting its trafficking. Evidence in normal cells showing that the scaffolding protein Na+/H+ exchanger regulatory factor 1 (NHERF1) can associate with EGFR to regulate its trafficking, led us to hypothesize that NHERF1 expression levels could regulate EGFR trafficking and functional expression in TNBC cells and, in this way, modulate its role in progression and response to treatment. We investigated the subcellular localization of NHERF1 and its interaction with EGFR in a metastatic basal like TNBC cell model, MDA-MB‑231, and the role of forced NHERF1 overexpression and/or stimulation with EGF on the sensitivity to EGFR specific TKI treatment with gefitinib. Stimulation with EGF induces an interaction of NHERF1 with EGFR to regulate its localization, degradation and function. NHERF1 overexpression is sufficient to drive its interaction with EGFR in non-stimulated conditions, inhibits EGFR degradation and increases its retention time in the plasma membrane. Importantly, NHERF1 overexpression strongly sensitized the cell to the pharmacological inhibition by gefitinib of EGFR-driven growth, motility and invadopodia-dependent ECM proteolysis. The further determination of how the NHERF1‑EGFR interaction is regulated may improve our understanding of TNBC resistance to the action of existing anticancer drugs.

  18. N1-guanyl-1,7-diaminoheptane sensitizes bladder cancer cells to doxorubicin by preventing epithelial-mesenchymal transition through inhibition of eukaryotic translation initiation factor 5A2 activation.

    Science.gov (United States)

    Yang, Jinsong; Yu, Haogang; Shen, Mo; Wei, Wei; Xia, Lihong; Zhao, Peng

    2014-02-01

    Drug resistance greatly reduces the efficacy of doxorubicin-based chemotherapy in bladder cancer treatment; however, the underlying mechanisms are poorly understood. We aimed to investigate whether N1-guanyl-1,7-diaminoheptane (GC7), which inhibits eukaryotic translation initiation factor 5A2 (eIF5A2) activation, exerts synergistic cytotoxicity with doxorubicin in bladder cancer, and whether eIF5A2 is involved in chemoresistance to doxorubicin-based bladder cancer treatment. BIU-87, J82, and UM-UC-3 bladder cancer cells were transfected with eIF5A2 siRNA or negative control siRNA before incubation with doxorubicin alone or doxorubicin plus GC7 for 48 h. Doxorubicin cytotoxicity was enhanced by GC7 in BIU-87, J82, and UM-UC-3 cells. It significantly inhibited activity of eIF5A2, suppressed doxorubicin-induced epithelial-mesenchymal transition in BIU-87 cells, and promoted mesenchymal-epithelial transition in J82 and UM-UC-3 cells. Knockdown of eIF5A2 sensitized bladder cancer cells to doxorubicin, prevented doxorubicin-induced EMT in BIU-87 cells, and encouraged mesenchymal-epithelial transition in J82 and UM-UC-3 cells. Combination therapy with GC7 may enhance the therapeutic efficacy of doxorubicin in bladder cancer by inhibiting eIF5A2 activation and preventing epithelial-mesenchymal transition.

  19. Influence of docosahexaenoic acid in vitro on intracellular adriamycin concentration in lymphocytes and human adriamycin-sensitive and -resistant small-cell lung cancer cell lines, and on cytotoxicity in the tumor cell lines

    NARCIS (Netherlands)

    Zijlstra, J G; de Vries, E G; Muskiet, F A; Martini, I A; Timmer-Bosscha, H; Mulder, N H

    1987-01-01

    An increase in the therapeutic effects of cancer chemotherapeutic agents and circumvention of drug resistance in cancer cells might result from an increase in the intracellular drug level. Alteration of the lipid domain of the cell membrane can result in a higher intracellular drug level. This alter

  20. Natural resistance to ascorbic acid induced oxidative stress is mainly mediated by catalase activity in human cancer cells and catalase-silencing sensitizes to oxidative stress

    Directory of Open Access Journals (Sweden)

    Klingelhoeffer Christoph

    2012-05-01

    Full Text Available Abstract Background Ascorbic acid demonstrates a cytotoxic effect by generating hydrogen peroxide, a reactive oxygen species (ROS involved in oxidative cell stress. A panel of eleven human cancer cell lines, glioblastoma and carcinoma, were exposed to serial dilutions of ascorbic acid (5-100 mmol/L. The purpose of this study was to analyse the impact of catalase, an important hydrogen peroxide-detoxifying enzyme, on the resistance of cancer cells to ascorbic acid mediated oxidative stress. Methods Effective concentration (EC50 values, which indicate the concentration of ascorbic acid that reduced the number of viable cells by 50%, were detected with the crystal violet assay. The level of intracellular catalase protein and enzyme activity was determined. Expression of catalase was silenced by catalase-specific short hairpin RNA (sh-RNA in BT-20 breast carcinoma cells. Oxidative cell stress induced apoptosis was measured by a caspase luminescent assay. Results The tested human cancer cell lines demonstrated obvious differences in their resistance to ascorbic acid mediated oxidative cell stress. Forty-five percent of the cell lines had an EC50 > 20 mmol/L and fifty-five percent had an EC50 50 of 2.6–5.5 mmol/L, glioblastoma cells were the most susceptible cancer cell lines analysed in this study. A correlation between catalase activity and the susceptibility to ascorbic acid was observed. To study the possible protective role of catalase on the resistance of cancer cells to oxidative cell stress, the expression of catalase in the breast carcinoma cell line BT-20, which cells were highly resistant to the exposure to ascorbic acid (EC50: 94,9 mmol/L, was silenced with specific sh-RNA. The effect was that catalase-silenced BT-20 cells (BT-20 KD-CAT became more susceptible to high concentrations of ascorbic acid (50 and 100 mmol/L. Conclusions Fifty-five percent of the human cancer cell lines tested were unable to protect themselves

  1. Feedback regulation of methyl methanesulfonate and ultraviolet-sensitive gene clone 81 via ATM/Chk2 pathway contributes to the resistance of MCF-7 breast cancer cells to cisplatin.

    Science.gov (United States)

    Lv, Juan; Qian, Ying; Ni, Xiaoyan; Xu, Xiuping; Dong, Xuejun

    2017-03-01

    The methyl methanesulfonate and ultraviolet-sensitive gene clone 81 protein is a structure-specific nuclease that plays important roles in DNA replication and repair. Knockdown of methyl methanesulfonate and ultraviolet-sensitive gene clone 81 has been found to sensitize cancer cells to chemotherapy. However, the underlying molecular mechanism is not well understood. We found that methyl methanesulfonate and ultraviolet-sensitive gene clone 81 was upregulated and the ATM/Chk2 pathway was activated at the same time when MCF-7 cells were treated with cisplatin. By using lentivirus targeting methyl methanesulfonate and ultraviolet-sensitive gene clone 81 gene, we showed that knockdown of methyl methanesulfonate and ultraviolet-sensitive gene clone 81 enhanced cell apoptosis and inhibited cell proliferation in MCF-7 cells under cisplatin treatment. Abrogation of ATM/Chk2 pathway inhibited cell viability in MCF-7 cells in response to cisplatin. Importantly, we revealed that ATM/Chk2 was required for the upregulation of methyl methanesulfonate and ultraviolet-sensitive gene clone 81, and knockdown of methyl methanesulfonate and ultraviolet-sensitive gene clone 81 resulted in inactivation of ATM/Chk2 pathway in response to cisplatin. Meanwhile, knockdown of methyl methanesulfonate and ultraviolet-sensitive gene clone 81 activated the p53/Bcl-2 pathway in response to cisplatin. These data suggest that the ATM/Chk2 may promote the repair of DNA damage caused by cisplatin by sustaining methyl methanesulfonate and ultraviolet-sensitive gene clone 81, and the double-strand breaks generated by methyl methanesulfonate and ultraviolet-sensitive gene clone 81 may activate the ATM/Chk2 pathway in turn, which provide a novel mechanism of how methyl methanesulfonate and ultraviolet-sensitive gene clone 81 modulates DNA damage response and repair.

  2. Acquired TGF beta 1 sensitivity and TGF beta 1 expression in cell lines established from a single small cell lung cancer patient during clinical progression

    DEFF Research Database (Denmark)

    Nørgaard, P; Damstrup, L; Rygaard, K;

    1996-01-01

    was found in GLC 16 and GLC 19. These cell lines were also growth inhibited by exogenously administrated TGF beta 1. TGF beta 1 mRNA and protein in its latent form was only expressed in the radiotherapy-resistant cell line, GLC 19. The results indicate that disease progression in this patient was paralleled...... by a gain in sensitivity to the growth inhibition by TGF beta 1 due to type II TGF beta receptor, and a gain of latent TGF beta 1 protein. Lack of type II receptor expression in GLC 14, which was also resistant to growth inhibition by exogenous TGF beta 1, was not due to gross structural changes in the type...

  3. Innate Lymphoid Cells in Cancer.

    Science.gov (United States)

    Vallentin, Blandine; Barlogis, Vincent; Piperoglou, Christelle; Cypowyj, Sophie; Zucchini, Nicolas; Chéné, Matthieu; Navarro, Florent; Farnarier, Catherine; Vivier, Eric; Vély, Frédéric

    2015-10-01

    The world of lymphocytes has recently expanded. A group of cells, innate lymphoid cells (ILC), has been defined. It includes lymphoid cells that have been known for decades, such as natural killer (NK) cells and lymphoid tissue-inducer (LTi) cells. NK cells recognize a vast array of tumor cells, which they help to eliminate through cytotoxicity and the production of cytokines, such as IFNγ. Advances in our understanding of NK-cell biology have led to a growing interest in the clinical manipulation of these cells in cancer. The other ILCs are found mostly in the mucosae and mucosal-associated lymphoid tissues, where they rapidly initiate immune responses to pathogens without the need for specific sensitization. Here, we outline the basic features of ILCs and review the role of ILCs other than NK cells in cancer. Much of the role of these ILCs in cancer remains unknown, but several findings should lead to further efforts to dissect the contribution of different ILC subsets to the promotion, maintenance, or elimination of tumors at various anatomic sites. This will require the development of standardized reagents and protocols for monitoring the presence and function of ILCs in human blood and tissue samples.

  4. Heat Shock Factor 1 Depletion Sensitizes A172 Glioblastoma Cells to Temozolomide via Suppression of Cancer Stem Cell-Like Properties

    Directory of Open Access Journals (Sweden)

    Chang-Nim Im

    2017-02-01

    Full Text Available Heat shock factor 1 (HSF1, a transcription factor activated by various stressors, regulates proliferation and apoptosis by inducing expression of target genes, such as heat shock proteins and Bcl-2 (B-cell lymphoma 2 interacting cell death suppressor (BIS. HSF1 also directly interacts with BIS, although it is still unclear whether this interaction is critical in the regulation of glioblastoma stem cells (GSCs. In this study, we examined whether small interfering RNA-mediated BIS knockdown decreased protein levels of HSF1 and subsequent nuclear localization under GSC-like sphere (SP-forming conditions. Consistent with BIS depletion, HSF1 knockdown also reduced sex determining region Y (SRY-box 2 (SOX2 expression, a marker of stemness, accompanying the decrease in SP-forming ability and matrix metalloprotease 2 (MMP2 activity. When HSF1 or BIS knockdown was combined with temozolomide (TMZ treatment, a standard drug used in glioblastoma therapy, apoptosis increased, as measured by an increase in poly (ADP-ribose polymerase (PARP cleavage, whereas cancer stem-like properties, such as colony-forming activity and SOX2 protein expression, decreased. Taken together, our findings suggest that targeting BIS or HSF1 could be a viable therapeutic strategy for GSCs resistant to conventional TMZ treatment.

  5. Heat Shock Factor 1 Depletion Sensitizes A172 Glioblastoma Cells to Temozolomide via Suppression of Cancer Stem Cell-Like Properties

    Science.gov (United States)

    Im, Chang-Nim; Yun, Hye Hyeon; Lee, Jeong-Hwa

    2017-01-01

    Heat shock factor 1 (HSF1), a transcription factor activated by various stressors, regulates proliferation and apoptosis by inducing expression of target genes, such as heat shock proteins and Bcl-2 (B-cell lymphoma 2) interacting cell death suppressor (BIS). HSF1 also directly interacts with BIS, although it is still unclear whether this interaction is critical in the regulation of glioblastoma stem cells (GSCs). In this study, we examined whether small interfering RNA-mediated BIS knockdown decreased protein levels of HSF1 and subsequent nuclear localization under GSC-like sphere (SP)-forming conditions. Consistent with BIS depletion, HSF1 knockdown also reduced sex determining region Y (SRY)-box 2 (SOX2) expression, a marker of stemness, accompanying the decrease in SP-forming ability and matrix metalloprotease 2 (MMP2) activity. When HSF1 or BIS knockdown was combined with temozolomide (TMZ) treatment, a standard drug used in glioblastoma therapy, apoptosis increased, as measured by an increase in poly (ADP-ribose) polymerase (PARP) cleavage, whereas cancer stem-like properties, such as colony-forming activity and SOX2 protein expression, decreased. Taken together, our findings suggest that targeting BIS or HSF1 could be a viable therapeutic strategy for GSCs resistant to conventional TMZ treatment. PMID:28241425

  6. Development of Nano-Liposomal Formulations of Epidermal Growth Factor Receptor Inhibitors and their Pharmacological Interactions on Drug-Sensitive and Drug-Resistant Cancer Cell Lines

    Science.gov (United States)

    Trummer, Brian J.

    , due to leaky tumor vasculature and the resulting Enhanced Permeability and Retention (EPR) phenomenon. In Chapter 2 we report that both gefitinib and the structurally similar EGFR inhibitor erlotinib display environment-dependent fluorescence properties. Peak excitation was 345 nm, and the emission peak ranged from 365 to 476 nm, depending upon the polarity of the environment and physical state of the drug. The fluorescence was negligible in aqueous solution, but intense in organic solvents or membrane bilayers. The environment-sensitive fluorescence properties of these drugs enabled rapid evaluation of numerous parameters affecting liposomal drug incorporation and performance. Up to 4-6 mol% of gefitinib could be incorporated in the liposome bilayer, based upon hydrophobic interactions with membrane bilayers. In contrast, 40-60 mol% could be loaded into the aqueous core of pre-formed liposomes at high efficiency, using a remote loading procedure. A stable formulation consisting of distearoylphosphatidylcholine: polyethylene glycol-distereoylphosphatidylethanolamine: cholesterol (DSPC:PEGDSPE:Chol, 9:1:5 mol:mol:mol) and containing drug at 50-60 mol% gefitinib (L-GEF) showed minimal leakage in serum-containing medium over 24 h at 37°C, which should be sufficient to improve biodistribution in vivo. Chapter 3 investigated the pharmacological activity of liposome-encapsulated gefitinib, alone and in combination with several prevalent anticancer agents. Experiments with MCF7 breast cancer cell lines demonstrated that liposome encapsulated gefitinib formulation (L-GEF) had a 2-fold higher IC50 (concentration of drug resulting in half-maximal growth inhibition) than free gefitinib. Lower in vitro potency would be consistent with delayed drug release from the carrier. Therapeutic effects were investigated in combination with the cytotoxic agents paclitaxel and doxorubicin. The drug-resistant MCF7R cell line was 23-fold more resistant to paclitaxel than the parental, drug-sensitive

  7. Argininosuccinate Synthase 1-Deficiency Enhances the Cell Sensitivity to Arginine through Decreased DEPTOR Expression in Endometrial Cancer

    Science.gov (United States)

    Ohshima, Kenji; Nojima, Satoshi; Tahara, Shinichiro; Kurashige, Masako; Hori, Yumiko; Hagiwara, Kohei; Okuzaki, Daisuke; Oki, Shinya; Wada, Naoki; Ikeda, Jun-ichiro; Kanai, Yoshikatsu; Morii, Eiichi

    2017-01-01

    Argininosuccinate synthetase 1 (ASS1) is a rate-limiting enzyme in arginine biosynthesis. Although ASS1 expression levels are often reduced in several tumors and low ASS1 expression can be a poor prognostic factor, the underlying mechanism has not been elucidated. In this study, we reveal a novel association between ASS1 and migration/invasion of endometrial tumors via regulation of mechanistic target of rapamycin complex (mTORC) 1 signaling. ASS1-knockout cells showed enhanced migration and invasion in response to arginine following arginine starvation. In ASS1-knockout cells, DEPTOR, an inhibitor of mTORC1 signal, was downregulated and mTORC1 signaling was more activated in response to arginine. ASS1 epigenetically enhanced DEPTOR expression by altering the histone methylation. Consistent with these findings, tumor cells at the invasive front of endometrioid carcinoma cases showed lower ASS1 and DEPTOR expression. Our findings suggest that ASS1 levels in each tumor cell are associated with invasion capability in response to arginine within the tumor microenvironment through mTORC1 signal regulation. PMID:28358054

  8. Effect of Saw Palmetto Supplements on Androgen-Sensitive LNCaP Human Prostate Cancer Cell Number and Syrian Hamster Flank Organ Growth

    Directory of Open Access Journals (Sweden)

    Alexander B. Opoku-Acheampong

    2016-01-01

    Full Text Available Saw palmetto supplements (SPS are commonly consumed by men with prostate cancer. We investigated whether SPS fatty acids and phytosterols concentrations determine their growth-inhibitory action in androgen-sensitive LNCaP cells and hamster flank organs. High long-chain fatty acids-low phytosterols (HLLP SPS ≥ 750 nM with testosterone significantly increased and ≥500 nM with dihydrotestosterone significantly decreased LNCaP cell number. High long-chain fatty acids-high phytosterols (HLHP SPS ≥ 500 nM with dihydrotestosterone and high medium-chain fatty acids-low phytosterols (HMLP SPS ≥ 750 nM or with androgens significantly decreased LNCaP cell number (n=3; p<0.05. Five- to six-week-old, castrated male Syrian hamsters were randomized to control (n=4, HLLP, HLHP, and HMLP SPS (n=6 groups. Testosterone or dihydrotestosterone was applied topically daily for 21 days to the right flank organ; the left flank organ was treated with ethanol and served as the control. Thirty minutes later, SPS or ethanol was applied to each flank organ in treatment and control groups, respectively. SPS treatments caused a notable but nonsignificant reduction in the difference between left and right flank organ growth in testosterone-treated SPS groups compared to the control. The same level of inhibition was not seen in dihydrotestosterone-treated SPS groups (p<0.05. Results may suggest that SPS inhibit 5α-reductase thereby preventing hamster flank organ growth.

  9. Effects of Livin Gene RNA Interference on Apoptosis of Cervical Cancer Hela Cells and Enhanced Sensitivity to Cisplatin

    Institute of Scientific and Technical Information of China (English)

    Lili YU; Zehua WANG

    2009-01-01

    The recombinant plasmids pGenesii-1-BIRC71 and pGenesil-1-BIRC72 were transfected into Hela cells and cisplatin was added with different concentrations in order to study the inhibitory ef-fects of Livin gene, increase the apoptosis induced by cisplatin, and detect the expression of Bcl-2, Bax,caspase-3, and survivin genes. The pGenesil-1-BIRC71 and pGenesil-1-BIRC72 were transfected into Hela cells, and the expression levels of Livin, Bcl-2, Bax, caspase-3, and survivin genes were detected by using fluorescence quantitative real-time PCR. Then cisplatin at different concentrations (3.0, 6.0 and 9.9 μg/mL) was added into the transfected Hela cells, and 24, and 48 h later, the apoptosis rate was measured by flow cytometry. After transfection of pGenesil-1-BIRC71 and pGenesil-1-BIRC72 into Hela cells, the expression level of Livin gene was obviously reduced, and the apoptosis rate was sig-nificantly increased in transfection group as compared with control group (P<0.05). Cisplatin could in-crease the apoptosis rate in a dose- and time-dependent manner. After cisplatin was added, the expres-sion levels of Bcl-2 mRNA were reduced, and those of Bax, caspase-3, and survivin mRNA were in-creased in transfection group as compared with those in control group (P<0.05). It was concluded that shRNA expression vector targeting Livin gene could inhibit the expression of Livin gene in Hela cells and enhance the apoptosis induced by cisplatin, which was related to the decreased expression of Bcl-2and activation of Bax and caspase-3. Survivin might play an important role as an antagonist in the proc-ess of apoptosis induction.

  10. Calcium insensitivity of FA-6, a cell line derived from a pancreatic cancer associated with humoral hypercalcemia, is mediated by the significantly reduced expression of the Calcium Sensitive Receptor transduction component p38 MAPK

    Directory of Open Access Journals (Sweden)

    Fairfax Benjamin

    2006-11-01

    Full Text Available Abstract The Calcium-Sensing Receptor is a key component of Calcium/Parathyroid hormone homeostatic system that helps maintain appropriate plasma Ca2+ concentrations. It also has a number of non-homeostatic functions, including cell cycle regulation through the p38 MAPK pathway, and recent studies have indicated that it is required for Ca2+ mediated growth arrest in pancreatic carcinoma cells. Some pancreatic cancers produce pathogenic amounts of parathyroid like hormones, however, which significantly increase Ca2+ plasma concentrations and might be expected to block further cell growth. In this study we have investigated the expression and function of the p38 MAPK signaling pathway in Ca2+ sensitive (T3M-4 and insensitive (FA6 pancreatic cancer cell lines. FA-6 cells, which are derived from a pancreatic adenocarcinoma that secretes a parathyroid hormone related peptide, exhibit only very low levels of p38 MAPK expression, relative to T3M-4 cells. Transfecting FA-6 cells with a p38 MAPK expression construct greatly increases their sensitivity to Ca2+. Furthermore, the reduction of p38 MAPK in T3M-4 cells significantly reduces the extent to which high levels of Ca2+ inhibit proliferation. These results suggest that the low levels of p38 MAPK expression in FA-6 cells may serve to reduce their sensitivity to high concentrations of external Ca2+ that would otherwise block proliferation.

  11. Response to mTOR inhibition: activity of eIF4E predicts sensitivity in cell lines and acquired changes in eIF4E regulation in breast cancer

    Directory of Open Access Journals (Sweden)

    Bartlett John MS

    2011-02-01

    Full Text Available Abstract Background Inhibitors of the kinase mTOR, such as rapamycin and everolimus, have been used as cancer therapeutics with limited success since some tumours are resistant. Efforts to establish predictive markers to allow selection of patients with tumours likely to respond have centred on determining phosphorylation states of mTOR or its targets 4E-BP1 and S6K in cancer cells. In an alternative approach we estimated eIF4E activity, a key effector of mTOR function, and tested the hypothesis that eIF4E activity predicts sensitivity to mTOR inhibition in cell lines and in breast tumours. Results We found a greater than three fold difference in sensitivity of representative colon, lung and breast cell lines to rapamycin. Using an assay to quantify influences of eIF4E on the translational efficiency specified by structured 5'UTRs, we showed that this estimate of eIF4E activity was a significant predictor of rapamycin sensitivity, with higher eIF4E activities indicative of enhanced sensitivity. Surprisingly, non-transformed cell lines were not less sensitive to rapamycin and did not have lower eIF4E activities than cancer lines, suggesting the mTOR/4E-BP1/eIF4E axis is deregulated in these non-transformed cells. In the context of clinical breast cancers, we estimated eIF4E activity by analysing expression of eIF4E and its functional regulators within tumour cells and combining these scores to reflect inhibitory and activating influences on eIF4E. Estimates of eIF4E activity in cancer biopsies taken at diagnosis did not predict sensitivity to 11-14 days of pre-operative everolimus treatment, as assessed by change in tumour cell proliferation from diagnosis to surgical excision. However, higher pre-treatment eIF4E activity was significantly associated with dramatic post-treatment changes in expression of eIF4E and 4E-binding proteins, suggesting that eIF4E is further deregulated in these tumours in response to mTOR inhibition. Conclusions

  12. Enhancement of Radiation Sensitivity in Lung Cancer Cells by a Novel Small Molecule Inhibitor That Targets the β-Catenin/Tcf4 Interaction.

    Science.gov (United States)

    Zhang, Qinghao; Gao, Mei; Luo, Guifen; Han, Xiaofeng; Bao, Wenjing; Cheng, Yanyan; Tian, Wang; Yan, Maocai; Yang, Guanlin; An, Jing

    2016-01-01

    Radiation therapy is an important treatment choice for unresectable advanced human lung cancers, and a critical adjuvant treatment for surgery. However, radiation as a lung cancer treatment remains far from satisfactory due to problems associated with radiation resistance in cancer cells and severe cytotoxicity to non-cancer cells, which arise at doses typically administered to patients. We have recently identified a promising novel inhibitor of β-catenin/Tcf4 interaction, named BC-23 (C21H14ClN3O4S), which acts as a potent cell death enhancer when used in combination with radiation. Sequential exposure of human p53-null non-small cell lung cancer (NSCLC) H1299 cells to low doses of x-ray radiation, followed 1 hour later by administration of minimally cytotoxic concentrations of BC-23, resulted in a highly synergistic induction of clonogenic cell death (combination index radiation effectiveness mediated by BC-23. BC-23 therefore represents a promising new class of radiation enhancer.

  13. Application of ZnO/graphene and S6 aptamers for sensitive photoelectrochemical detection of SK-BR-3 breast cancer cells based on a disposable indium tin oxide device.

    Science.gov (United States)

    Liu, Fang; Zhang, Yan; Yu, Jinghua; Wang, Shaowei; Ge, Shenguang; Song, Xianrang

    2014-01-15

    ZnO/graphene (ZnO/G) composite and S6 aptamer were employed to sensitive photoelectrochemical (PEC) strategy for the specific detection of SK-BR-3 cancer cells based on a portable indium tin oxide microdevice. ZnO/G composite was synthesized using a facile ultrasonic method, and then applied to improve the PEC performance due to the unique hollow structure of ZnO naospheres and the superior properties of graphene. Subsequently, S6 aptamer was applied to this specific detection of SK-BR-3 cancer cells. And the concentration of SK-BR-3 cells was measured with a low detection limit of 58 cells mL(-1) and a wide linear range of 1×10(2)-1×10(6) cells mL(-1), through the decrease in photocurrent intensity resulting from the increase in steric hindrances when specifically recognized with S6 aptamers. Excellent discrimination against target and analogous cells was demonstrated, indicating the high selectivity of the proposed cell sensor. Our work also demonstrated a sensitive, stable and low cytotoxicity approach for early and accurate detection of cancer cells.

  14. Resveratrol induces apoptosis in pancreatic cancer cells

    Institute of Scientific and Technical Information of China (English)

    ZHOU Jia-hua; CHENG Hai-yan; YU Ze-qian; HE Dao-wei; PAN Zheng; YANG De-tong

    2011-01-01

    Background Pancreatic cancer is one of the most lethal human cancers with a very low survival rate of 5 years.Conventional cancer treatments including surgery, radiation, chemotherapy or combinations of these show little effect on this disease. Several proteins have been proved critical to the development and the progression of pancreatic cancer.The aim of this study was to investigate the effect of resveratrol on apoptosis in pancreatic cancer cells.Methods Several pancreatic cancer cell lines were screened by resveratrol, and its toxicity was tested by normal pancreatic cells. Western blotting was then performed to analyze the molecular mechanism of resveratrol induced apoptosis of pancreatic cancer cell lines.Results In the screened pancreatic cancer cell lines, capan-2 and colo357 showed high sensitivity to resveratrol induced apoptosis. Resveratrol exhibited insignificant toxicity to normal pancreatic cells. In resveratrol sensitive cells,capan-2 and colo357, the activation of caspase-3 was detected and showed significant caspase-3 activation upon resveratrol treatment; p53 and p21 were also detected up-regulated upon resveratrol treatment.Conclusion Resveratrol provides a promising anti-tumor stratagy to fight against pancreatic cancer.

  15. Sensitivity and specificity of the empirical lymphocyte genome sensitivity (LGS) assay: implications for improving cancer diagnostics.

    Science.gov (United States)

    Anderson, Diana; Najafzadeh, Mojgan; Gopalan, Rajendran; Ghaderi, Nader; Scally, Andrew J; Britland, Stephen T; Jacobs, Badie K; Reynolds, P Dominic; Davies, Justin; Wright, Andrew L; Al-Ghazal, Shariff; Sharpe, David; Denyer, Morgan C

    2014-10-01

    Lymphocyte responses from 208 individuals: 20 with melanoma, 34 with colon cancer, and 4 with lung cancer (58), 18 with suspected melanoma, 28 with polyposis, and 10 with COPD (56), and 94 healthy volunteers were examined. The natural logarithm of the Olive tail moment (OTM) was plotted for exposure to UVA through 5 different agar depths (100 cell measurements/depth) and analyzed using a repeated measures regression model. Responses of patients with cancer plateaued after treatment with different UVA intensities, but returned toward control values for healthy volunteers. For precancerous conditions and suspected cancers, intermediate responses occurred. ROC analysis of mean log OTMs, for cancers plus precancerous/suspect conditions vs. controls, cancer vs. precancerous/suspect conditions plus controls, and cancer vs. controls, gave areas under the curve of 0.87, 0.89, and 0.93, respectively (P<0.001). Optimization allowed test sensitivity or specificity to approach 100% with acceptable complementary measures. This modified comet assay could represent a stand-alone test or an adjunct to other investigative procedures for detecting cancer.

  16. Radiation sensitivity of Merkel cell carcinoma cell lines

    Energy Technology Data Exchange (ETDEWEB)

    Leonard, J.H.; Ramsay, J.R.; Birrell, G.W. [Queensland Institute of Medical Research (Australia)] [and others

    1995-07-30

    Merkel cell carcinoma (MCC), being a small cell carcinoma, would be expected to be sensitive to radiation. Clinical analysis of patients at our center, especially those with macroscopic disease, would suggest the response is quite variable. We have recently established a number of MCC cell lines from patients prior to radiotherapy, and for the first time are in a position to determine their sensitivity under controlled conditions. Some of the MCC lines grew as suspension cultures and could not be single cell cloned; therefore, it was not possible to use clonogenic survival for all cell lines. A tetrazolium based (MTT) assay was used for these lines, to estimate cell growth after {gamma} irradiation. Control experiments were conducted on lymphoblastoid cell lines (LCL) and the adherent MCC line, MCC13, to demonstrate that the two assays were comparable under the conditions used. We have examined cell lines from MCC, small cell lung cancer (SCLC), malignant melanomas, Epstein Barr virus (EBV) transformed lymphocytes (LCL), and skin fibroblasts for their sensitivity to {gamma} irradiation using both clonogenic cell survival and MTT assays. The results show that the tumor cell lines have a range of sensitivities, with melanoma being more resistant (surviving fraction at 2 Gy (SF2) 0.57 and 0.56) than the small cell carcinoma lines, MCC (SF2 range 0.21-0.45, mean SF2 0.30, n = 8) and SCLC (SF2 0.31). Fibroblasts were the most sensitive (SF2 0.13-0.20, mean 0.16, n = 5). The MTT assay, when compared to clonogenic assay for the MCC13 adherent line and the LCL, gave comparable results under the conditions used. Both assays gave a range of SF2 values for the MCC cell lines, suggesting that these cancers would give a heterogeneous response in vivo. The results with the two derivative clones of MCC14 (SF2 for MCC14/1 0.38, MCC14/2 0.45) would further suggest that some of them may develop resistance during clonogenic evolution. 25 refs., 3 figs., 1 tab.

  17. Magnesium homeostasis in colon carcinoma LoVo cells sensitive or resistant to doxorubicin

    OpenAIRE

    2015-01-01

    Neoplastic cells accumulate magnesium, an event which provides selective advantages and is frequently associated with TRPM7overexpression. Little is known about magnesium homeostasis in drug-resistant cancer cells. Therefore, we used the colon cancer LoVo cell model and compared doxorubicin-resistant to sensitive cells. In resistant cells the concentration of total magnesium is higher while its influx capacity is lower than in sensitive cells. Accordingly, resistant cells express lower amount...

  18. Selection of a MCF-7 Breast Cancer Cell Subpopulation with High Sensitivity to IL-1β: Characterization of and Correlation between Morphological and Molecular Changes Leading to Increased Invasiveness

    Directory of Open Access Journals (Sweden)

    Eloy Andres Pérez-Yépez

    2012-01-01

    Full Text Available Cancer and inflammation are closely related in tumor malignancy prognosis. Breast cancer MCF-7 cells have a poor invasive phenotype, although, under IL-1β stimulus, acquire invasive features. Cell response heterogeneity has precluded precise evaluation of the malignant transition. MCF-7A3 cells were selected for high sensitivity to IL-1β stimulus, uniform expression of CXCR4, and stability of IL1-RI. Structural changes, colony formation ability, proliferation rate, chemotaxis, Matrigel invasion, E-cadherin mRNA expression and protein localization were determined in these cells and in MCF-7 parental cells under the stimulus of IL-1β. Selected MCF-7A3 cells showed a uniform response to IL-1β stimulation increasing features of invasive cells such as scattering, colony formation, proliferation, chemokinesis and invasion. Basal expression of E-cadherin mRNA was higher, and IL-1β stimulus had no further effect at early times of cytokine exposure. Total E-cadherin levels remained unchanged in parental cells, whereas levels decreased, as MCF-7A3 cells became fibroblastoid or scattered. Triton X-100 soluble/insoluble E-cadherin ratios were highly increased in these cells, while, in MCF-7pl cells, ratios could not be correlated with morphology changes. MCF-7A3 cells uniform response to IL-1β allowed characterization of changes induced by the cytokine that had not been assessed when using heterogeneous cell lines.

  19. Inflammation and cancer stem cells.

    Science.gov (United States)

    Shigdar, Sarah; Li, Yong; Bhattacharya, Santanu; O'Connor, Michael; Pu, Chunwen; Lin, Jia; Wang, Tao; Xiang, Dongxi; Kong, Lingxue; Wei, Ming Q; Zhu, Yimin; Zhou, Shufeng; Duan, Wei

    2014-04-10

    Cancer stem cells are becoming recognised as being responsible for metastasis and treatment resistance. The complex cellular and molecular network that regulates cancer stem cells and the role that inflammation plays in cancer progression are slowly being elucidated. Cytokines, secreted by tumour associated immune cells, activate the necessary pathways required by cancer stem cells to facilitate cancer stem cells progressing through the epithelial-mesenchymal transition and migrating to distant sites. Once in situ, these cancer stem cells can secrete their own attractants, thus providing an environment whereby these cells can continue to propagate the tumour in a secondary niche.

  20. Sensitivity to Radiation-Induced Cancer in Hemochromatosis

    Energy Technology Data Exchange (ETDEWEB)

    Bull. Richard J.; Anderson, Larry E.

    2000-06-01

    The objectives of this pilot project using HFE-knockout homozygotes and heterozygotes are to (1) determine whether the knock-out mice have greater sensitivity to radiation-induced cancer of the colon, liver and breast, (2) establish the dependence of this sensitivity on the accumulation of iron, (3) determine the extent to which cell replication and apoptosis occur in these target tissues with varying iron load, and (4) correlate the increases in sensitivity with changes in insulin-related signaling in tumors and normal tissue from each target organ. Three experimental designs will be used in the pilot project. The sequence of experiments is designed to first explore the influence of iron load on the response and demonstrate that HFE knockout mice are more sensitive than the wild type to radiation-induced cancer in one or more of three target tissues (liver, colon and breast). The dose response relationships with a broader set of radiation doses will be explored in the second experiment. The final experiment is designed to explore the extent to which heterozygotes display the increased susceptibility to cancer induction and to independently assess the importance of iron load to the initiation versus promotion of tumors.

  1. BIM Gene Polymorphism Lowers the Efficacy of EGFR-TKIs in Advanced Nonsmall Cell Lung Cancer With Sensitive EGFR Mutations: A Systematic Review and Meta-Analysis.

    Science.gov (United States)

    Huang, Wu Feng; Liu, Ai Hua; Zhao, Hai Jin; Dong, Hang Ming; Liu, Lai Yu; Cai, Shao Xi

    2015-08-01

    The strong association between bcl-2-like 11 (BIM) triggered apoptosis and the presence of epidermal growth factor receptor (EGFR) mutations has been proven in nonsmall cell lung cancer (NSCLC). However, the relationship between EGFR-tyrosine kinase inhibitor's (TKI's) efficacy and BIM polymorphism in NSCLC EGFR is still unclear.Electronic databases were searched for eligible literatures. Data on objective response rates (ORRs), disease control rates (DCRs), and progression-free survival (PFS) stratified by BIM polymorphism status were extracted and synthesized based on random-effect model. Subgroup and sensitivity analyses were conducted.A total of 6 studies that involved a total of 773 EGFR mutant advanced NSCLC patients after EGFR-TKI treatment were included. In overall, non-BIM polymorphism patients were associated with significant prolonged PFS (hazard ratio 0.63, 0.47-0.83, P = 0.001) compared to patients with BIM polymorphism. However, only marginal improvements without statistical significance in ORR (odds ratio [OR] 1.71, 0.91-3.24, P = 0.097) and DCR (OR 1.56, 0.85-2.89, P = 0.153) were observed. Subgroup analyses showed that the benefits of PFS in non-BIM polymorphism group were predominantly presented in pooled results of studies involving chemotherapy-naive and the others, and retrospective studies. Additionally, we failed to observe any significant benefit from patients without BIM polymorphism in every subgroup for ORR and DCR.For advanced NSCLC EGFR mutant patients, non-BIM polymorphism ones are associated with longer PFS than those with BIM polymorphism after EGFR-TKIs treatment. BIM polymorphism status should be considered an essential factor in studies regarding EGFR-targeted agents toward EGFR mutant patients.

  2. Cancer stem cells, cancer cell plasticity and radiation therapy.

    Science.gov (United States)

    Vlashi, Erina; Pajonk, Frank

    2015-04-01

    Since the first prospective identification of cancer stem cells in solid cancers the cancer stem cell hypothesis has reemerged as a research topic of increasing interest. It postulates that solid cancers are organized hierarchically with a small number of cancer stem cells driving tumor growth, repopulation after injury and metastasis. They give rise to differentiated progeny, which lack these features. The model predicts that for any therapy to provide cure, all cancer stem cells have to be eliminated while the survival of differentiated progeny is less critical. In this review we discuss recent reports challenging the idea of a unidirectional differentiation of cancer cells. These reports provide evidence supporting the idea that non-stem cancer cells exhibit a remarkable degree of plasticity that allows them to re-acquire cancer stem cell traits, especially in the context of radiation therapy. We summarize conditions under which differentiation is reversed and discuss the current knowledge of the underlying mechanisms.

  3. Attenuation of the DNA Damage Response by Transforming Growth Factor-Beta Inhibitors Enhances Radiation Sensitivity of Non–Small-Cell Lung Cancer Cells In Vitro and In Vivo

    Energy Technology Data Exchange (ETDEWEB)

    Du, Shisuo; Bouquet, Sophie; Lo, Chen-Hao; Pellicciotta, Ilenia; Bolourchi, Shiva [Department of Radiation Oncology, New York University School of Medicine, New York, New York (United States); Parry, Renate [Varian Medical Systems, Palo Alto, California (United States); Barcellos-Hoff, Mary Helen, E-mail: mhbarcellos-hoff@nyumc.org [Department of Radiation Oncology, New York University School of Medicine, New York, New York (United States)

    2015-01-01

    Purpose: To determine whether transforming growth factor (TGF)-β inhibition increases the response to radiation therapy in human and mouse non–small-cell lung carcinoma (NSCLC) cells in vitro and in vivo. Methods and Materials: TGF-β–mediated growth response and pathway activation were examined in human NSCLC NCI-H1299, NCI-H292, and A549 cell lines and murine Lewis lung cancer (LLC) cells. Cells were treated in vitro with LY364947, a small-molecule inhibitor of the TGF-β type 1 receptor kinase, or with the pan-isoform TGF-β neutralizing monoclonal antibody 1D11 before radiation exposure. The DNA damage response was assessed by ataxia telangiectasia mutated (ATM) or Trp53 protein phosphorylation, γH2AX foci formation, or comet assay in irradiated cells. Radiation sensitivity was determined by clonogenic assay. Mice bearing syngeneic subcutaneous LLC tumors were treated with 5 fractions of 6 Gy and/or neutralizing or control antibody. Results: The NCI-H1299, A549, and LLC NSCLC cell lines pretreated with LY364947 before radiation exposure exhibited compromised DNA damage response, indicated by decreased ATM and p53 phosphorylation, reduced γH2AX foci, and increased radiosensitivity. The NCI-H292 cells were unresponsive. Transforming growth factor-β signaling inhibition in irradiated LLC cells resulted in unresolved DNA damage. Subcutaneous LLC tumors in mice treated with TGF-β neutralizing antibody exhibited fewer γH2AX foci after irradiation and significantly greater tumor growth delay in combination with fractionated radiation. Conclusions: Inhibition of TGF-β before radiation attenuated DNA damage recognition and increased radiosensitivity in most NSCLC cells in vitro and promoted radiation-induced tumor control in vivo. These data support the rationale for concurrent TGF-β inhibition and RT to provide therapeutic benefit in NSCLC.

  4. Relationship between Expression of β-tubulin-Ⅲ Plus Stathmin in Advanced Non-Small Cell Lung Cancer and its Sensitivity to Venorelbine Chemotherapy

    Directory of Open Access Journals (Sweden)

    Xiaolin PU

    2009-01-01

    Full Text Available Background and objective Vinorelbine plus cisplatin/carboplatin (NP is one of the standard combination chemotherapy regimen for advanced non-small cell lung cancer (NSCLC. The aim of this study is toinvestigate the relationship between expression of Stathmin and β-tubulin-Ⅲ in NSCLC biopsies and sensitivity to Vinorelbine, which would provide a basis of the proper medicine choice for the patients' tailored chemotherapy. Methods Western blot was used to investigate the expression of Stathmin and β-tubulin-Ⅲ protein in the biopsies from stage ⅢB-Ⅳ NSCLC patients. All the cases were divided into 4 groups according to the level of the two proteins, of which L represented both protein expressed lowly, B showed β-tubulin-Ⅲ lowly expressed group, while S showed Stathmin lowly, and H represented both protein highly expressed. At the same time, all the patients accepted NP chemotherapy for 2 or 4 cycles according to the responses to this regimen. The responses rate (RR, media survival time (MST, time to progress (TTP were observed. Results A total of 90 stage ⅢB-Ⅳ NSCLC patients were divided into 4 groups, 22 in L group, 23 in B and S group while 22 in H group respectively. The RR of the groups were 68.2%, 26.1%, 30.4% and 22.7% respectively.There were statistically significant differences between L group and other 3 groups (P <0.05. The MST were 377, 305, 321 and 271 days respectively, and the TTP were 240, 182, 190 and 166 days in the 4 groups. Statistically significant differences between L group and other 3 groups (P <0.05 can be seen in both MST and TTP. Conclusion The expression of β-tubulin-Ⅲ and Stathmin in advanced NSCLC biopsies had relationship with the sensitivity to NP chemotherapyregimen in the patients. Cases with high level of these two proteins would have poor responses to this cytotoxic drug.

  5. Glutathione in Cancer Cell Death

    Directory of Open Access Journals (Sweden)

    Jose M. Estrela

    2011-03-01

    Full Text Available Glutathione (L-γ-glutamyl-L-cysteinyl-glycine; GSH in cancer cells is particularly relevant in the regulation of carcinogenic mechanisms; sensitivity against cytotoxic drugs, ionizing radiations, and some cytokines; DNA synthesis; and cell proliferation and death. The intracellular thiol redox state (controlled by GSH is one of the endogenous effectors involved in regulating the mitochondrial permeability transition pore complex and, in consequence, thiol oxidation can be a causal factor in the mitochondrion-based mechanism that leads to cell death. Nevertheless GSH depletion is a common feature not only of apoptosis but also of other types of cell death. Indeed rates of GSH synthesis and fluxes regulate its levels in cellular compartments, and potentially influence switches among different mechanisms of death. How changes in gene expression, post-translational modifications of proteins, and signaling cascades are implicated will be discussed. Furthermore, this review will finally analyze whether GSH depletion may facilitate cancer cell death under in vivo conditions, and how this can be applied to cancer therapy.

  6. Glutathione in Cancer Cell Death

    Energy Technology Data Exchange (ETDEWEB)

    Ortega, Angel L. [Department of Physiology, Faculty of Medicine and Odontology, University of Valencia, 17 Av. Blasco Ibanez, 46010 Valencia (Spain); Mena, Salvador [Green Molecular SL, Pol. Ind. La Coma-Parc Cientific, 46190 Paterna, Valencia (Spain); Estrela, Jose M., E-mail: jose.m.estrela@uv.es [Department of Physiology, Faculty of Medicine and Odontology, University of Valencia, 17 Av. Blasco Ibanez, 46010 Valencia (Spain)

    2011-03-11

    Glutathione (L-γ-glutamyl-L-cysteinyl-glycine; GSH) in cancer cells is particularly relevant in the regulation of carcinogenic mechanisms; sensitivity against cytotoxic drugs, ionizing radiations, and some cytokines; DNA synthesis; and cell proliferation and death. The intracellular thiol redox state (controlled by GSH) is one of the endogenous effectors involved in regulating the mitochondrial permeability transition pore complex and, in consequence, thiol oxidation can be a causal factor in the mitochondrion-based mechanism that leads to cell death. Nevertheless GSH depletion is a common feature not only of apoptosis but also of other types of cell death. Indeed rates of GSH synthesis and fluxes regulate its levels in cellular compartments, and potentially influence switches among different mechanisms of death. How changes in gene expression, post-translational modifications of proteins, and signaling cascades are implicated will be discussed. Furthermore, this review will finally analyze whether GSH depletion may facilitate cancer cell death under in vivo conditions, and how this can be applied to cancer therapy.

  7. Protons Sensitize Epithelial Cells to Mesenchymal Transition

    Science.gov (United States)

    Wang, Minli; Hada, Megumi; Saha, Janapriya; Sridharan, Deepa M.; Pluth, Janice M.; Cucinotta, Francis A.

    2012-01-01

    Proton radiotherapy has gained more favor among oncologists as a treatment option for localized and deep-seated tumors. In addition, protons are a major constituent of the space radiation astronauts receive during space flights. The potential for these exposures to lead to, or enhance cancer risk has not been well studied. Our objective is to study the biological effects of low energy protons on epithelial cells and its propensity to enhance transforming growth factor beta 1 (TGFβ1)-mediated epithelial-mesenchymal transition (EMT), a process occurring during tumor progression and critical for invasion and metastasis. Non-transformed mink lung epithelial cells (Mv1Lu) and hTERT- immortalized human esophageal epithelial cells (EPC) were used in this study. EMT was identified by alterations in cell morphology, EMT-related gene expression changes determined using real-time PCR, and EMT changes in specific cellular markers detected by immunostaining and western blotting. Although TGFβ1 treatment alone is able to induce EMT in both Mv1Lu and EPC cells, low energy protons (5 MeV) at doses as low as 0.1 Gy can enhance TGFβ1 induced EMT. Protons alone can also induce a mild induction of EMT. SD208, a potent TGFβ Receptor 1 (TGFβR1) kinase inhibitor, can efficiently block TGFβ1/Smad signaling and attenuate EMT induction. We suggest a model for EMT after proton irradiation in normal and cancerous tissue based on our results that showed that low and high doses of protons can sensitize normal human epithelial cells to mesenchymal transition, more prominently in the presence of TGFβ1, but also in the absence of TGFβ1. PMID:22844446

  8. Protons sensitize epithelial cells to mesenchymal transition.

    Directory of Open Access Journals (Sweden)

    Minli Wang

    Full Text Available Proton radiotherapy has gained more favor among oncologists as a treatment option for localized and deep-seated tumors. In addition, protons are a major constituent of the space radiation astronauts receive during space flights. The potential for these exposures to lead to, or enhance cancer risk has not been well studied. Our objective is to study the biological effects of low energy protons on epithelial cells and its propensity to enhance transforming growth factor beta 1 (TGFβ1-mediated epithelial-mesenchymal transition (EMT, a process occurring during tumor progression and critical for invasion and metastasis. Non-transformed mink lung epithelial cells (Mv1Lu and hTERT- immortalized human esophageal epithelial cells (EPC were used in this study. EMT was identified by alterations in cell morphology, EMT-related gene expression changes determined using real-time PCR, and EMT changes in specific cellular markers detected by immunostaining and western blotting. Although TGFβ1 treatment alone is able to induce EMT in both Mv1Lu and EPC cells, low energy protons (5 MeV at doses as low as 0.1 Gy can enhance TGFβ1 induced EMT. Protons alone can also induce a mild induction of EMT. SD208, a potent TGFβ Receptor 1 (TGFβR1 kinase inhibitor, can efficiently block TGFβ1/Smad signaling and attenuate EMT induction. We suggest a model for EMT after proton irradiation in normal and cancerous tissue based on our results that showed that low and high doses of protons can sensitize normal human epithelial cells to mesenchymal transition, more prominently in the presence of TGFβ1, but also in the absence of TGFβ1.

  9. Relevance of mortalin to cancer cell stemness and cancer therapy.

    Science.gov (United States)

    Yun, Chae-Ok; Bhargava, Priyanshu; Na, Youjin; Lee, Jung-Sun; Ryu, Jihoon; Kaul, Sunil C; Wadhwa, Renu

    2017-02-06

    Mortalin/mtHsp70 is a member of Hsp70 family of proteins. Enriched in a large variety of cancers, it has been shown to contribute to the process of carcinogenesis by multiple ways including inactivation of tumor suppressor p53 protein, deregulation of apoptosis and activation of EMT signaling. In this study, we report that upregulation of mortalin contributes to cancer cell stemness. Several cancer cell stemness markers, such as ABCG2, OCT-4, CD133, ALDH1, CD9, MRP1 and connexin were upregulated in mortalin-overexpressing cells that showed higher ability to form spheroids. These cells also showed higher migration, and were less responsive to a variety of cancer chemotherapeutic drugs. Of note, knockdown of mortalin by specific shRNA sensitized these cells to all the drugs used in this study. We report that low doses of anti-mortalin molecules, MKT-077 and CAPE, also caused similar sensitization of cancer cells to chemotherapeutic drugs and hence are potential candidates for effective cancer chemotherapy.

  10. Relevance of mortalin to cancer cell stemness and cancer therapy

    Science.gov (United States)

    Yun, Chae-Ok; Bhargava, Priyanshu; Na, Youjin; Lee, Jung-Sun; Ryu, Jihoon; Kaul, Sunil C.; Wadhwa, Renu

    2017-01-01

    Mortalin/mtHsp70 is a member of Hsp70 family of proteins. Enriched in a large variety of cancers, it has been shown to contribute to the process of carcinogenesis by multiple ways including inactivation of tumor suppressor p53 protein, deregulation of apoptosis and activation of EMT signaling. In this study, we report that upregulation of mortalin contributes to cancer cell stemness. Several cancer cell stemness markers, such as ABCG2, OCT-4, CD133, ALDH1, CD9, MRP1 and connexin were upregulated in mortalin-overexpressing cells that showed higher ability to form spheroids. These cells also showed higher migration, and were less responsive to a variety of cancer chemotherapeutic drugs. Of note, knockdown of mortalin by specific shRNA sensitized these cells to all the drugs used in this study. We report that low doses of anti-mortalin molecules, MKT-077 and CAPE, also caused similar sensitization of cancer cells to chemotherapeutic drugs and hence are potential candidates for effective cancer chemotherapy. PMID:28165047

  11. Molecular Modification of Metadherin/MTDH Impacts the Sensitivity of Breast Cancer to Doxorubicin.

    Directory of Open Access Journals (Sweden)

    Zhenchuan Song

    Full Text Available Breast cancer is a leading cause of death in women and with an increasing worldwide incidence. Doxorubicin, as a first-line anthracycline-based drug is conventional used on breast cancer clinical chemotherapy. However, the drug resistances limited the curative effect of the doxorubicin therapy in breast cancer patients, but the molecular mechanism determinants of breast cancer resistance to doxorubicin chemotherapy are not fully understood. In order to explore the association between metadherin (MTDH and doxorubicin sensitivity, the differential expressions of MTDH in breast cancer cell lines and the sensitivity to doxorubicin of breast cancer cell lines were investigated.The mRNA and protein expression of MTDH were determined by real-time PCR and Western blot in breast cancer cells such as MDA-MB-231, MCF-7, MDA-MB-435S, MCF-7/ADR cells. Once MTDH gene was knocked down by siRNA in MCF-7/ADR cells and overexpressed by MTDH plasmid transfection in MDA-MB-231 cells, the cell growth and therapeutic sensitivity of doxorubicin were evaluated using MTT and the Cell cycle assay and apoptosis rate was determined by flow cytometry.MCF-7/ADR cells revealed highly expressed MTDH and MDA-MB-231 cells had the lowest expression of MTDH. After MTDH gene was knocked down, the cell proliferation was inhibited, and the inhibitory rate of cell growth and apoptosis rate were enhanced, and the cell cycle arrest during the G0/G1 phase in the presence of doxorubicin treatment. On the other hand, the opposite results were observed in MDA-MB-231 cells with overexpressed MTDH gene.MTDH gene plays a promoting role in the proliferation of breast cancer cells and its high expression may be associated with doxorubicin sensitivity of breast cancer.

  12. Increases in doxorubicin sensitivity and radioiodide uptake by transfecting shMDR and sodium/iodide symporter gene in cancer cells expressing multidrug resistance

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, Sohn Joo; Lee, Yong Jin; Lee, You La; Choi, Chang Ik; Lee, Sang Woo; Yoo, Jeong Soo; Ahn, Byeong Cheol; Lee, In Kyu; Lee, Jae Tae [Kyungpook National University, Daegu (Korea, Republic of)

    2007-06-15

    Multidrug resistance (MDR) of the cancer cells related to mdr1 gene expression can be effectively treated by selective short hairpin RNA for mdr1 gene (shMDR). Sodium/iodide symporter (NIS) gene is well known to have both reporter and therapeutic gene characteristics. We have co-transfected both shMDR and NIS gene into colon cancer cells (HCT15 cell) expressing MDR and Tc-99m sestamibi and I-125 uptake were measured. In addition, cytotoxic effects of doxorubicin and I-131 therapy were also assessed after transfection. At first, shMDR was transfected with liposome reagent into human embryonic kidney cells (HEK293) and HCT cells. shMDR transfection was confirmed by RT-PCR and western blot analysis. Adenovirus expressing NIS (Ad-NIS) gene and shMDR (Ad-shMDR) were co-transfected with Ad-NIS into HCT15 cells. Forty-eight hours after infection, inhibition of P-gycoprotein (Pgp) function by shMDR was analyzed by a change of Tc-99m sestamibi uptake and doxorubicin cytotoxicity, and functional activity of induced NIS gene expression was assessed with I-125 uptake assay. In HEK293 cells transfected with shMDR, mdr1 mRNA and Pgp protein expressions were down regulated. HCT15 cells infected with 20 MOI of Ad-NIS was higher NIS protein expression than control cells. After transfection of 300 MOI of Ad-shMDR either with or without 10 MOI of Ad-NIS, uptake of Tc-99m sestamibi increased up to 1.5-fold than control cells. HCT15 cells infected with 10 MOI of Ad-NIS showed approximately 25-fold higher I-125 uptake than control cells. Cotransfection of Ad-shMDR and Ad-NIS resulted in enhanced cytotoxic by doxorubicin in HCT15 cells. I-131 treatment on HCT15 cells infected with 20 MOI of Ad-NIS revealed increased cytotoxic effect. Suppression of mdr1 gene expression, retention of Tc-99m sestamibi, enhanced doxorubicin cytotoxicity and increases in I-125 uptake were achieved in MDR expressing cancer cell by co-transfection of shMDR and NIS gene. Dual therapy with doxorubicin and

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

    Science.gov (United States)

    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.

  14. Cytotoxic, apoptotic, and sensitization properties of ent-kaurane-type diterpenoids from Croton tonkinensis Gagnep on human liver cancer HepG2 and Hep3b cell lines.

    Science.gov (United States)

    Pham, Minh Quan; Iscache, Anne Laure; Pham, Quoc Long; Gairin, Jean Edouard

    2016-04-01

    Human hepatocellular carcinoma (HCC) is the most common type of liver cancer, the second most common cause of death from cancer worldwide. A very poor prognosis and a lack of effective treatments make liver cancer a major public health problem, notably in less developed regions, particularly in eastern Asia. This fully justifies the search of new molecules and therapeutic strategies against HCC. Ent-kaurane diterpenoids are natural compounds displaying a broad spectrum of potential therapeutic effects including anticancer activity. In this study, we analyzed the pharmacological properties of a family of ent-kaurane diterpenoids from Croton tonkinensis Gagnep in human HepG2 and Hep3b cell lines, used as cellular reference models for in vitro evaluation of new molecules active on HCC. A structure-related cytotoxicity was observed against both HCC cell lines, enlighting the role of the 16-en-15-one skeleton of ent-kaurane diterpenoids. Cytotoxicity was closely correlated to apoptosis, evidenced by concentration-dependent subG1 cell accumulation, and increased annexin V expression. In addition, subtoxic concentration of ent-kaurane diterpenoid dramatically enhanced the sensitivity of HCC cells to doxorubicin. All together, our data bring strong support to the potential interest of ent-kaurane diterpenoids, alone or in combination with a cytotoxic agent, in cancer and more precisely against HCC.

  15. Comparative Study of 17-AAG and NVP-AUY922 in Pancreatic and Colorectal Cancer Cells: Are There Common Determinants of Sensitivity?

    Directory of Open Access Journals (Sweden)

    Leticia Mayor-López

    2014-10-01

    Full Text Available The use of heat shock protein 90 (Hsp90 inhibitors is an attractive antineoplastic therapy. We wanted to compare the effects of the benzoquinone 17-allylamino-17-demethoxygeldanamycin (17-AAG, tanespimycin and the novel isoxazole resorcinol–based Hsp90 inhibitor NVP-AUY922 in a panel of pancreatic and colorectal carcinoma cell lines and in colorectal primary cultures derived from tumors excised to patients. PANC-1, CFPAC-1, and Caco-2 cells were intrinsically resistant to 17-AAG but sensitive to NVP-AUY922. Other cellular models were sensitive to both inhibitors. Human epidermal growth factor receptor receptors and their downstream signaling pathways were downregulated in susceptible cellular models, and concurrently, Hsp70 was induced. Intrinsic resistance to 17-AAG did not correlate with expression of ATP-binding cassette transporters involved in multidrug resistance. Some 17-AAG-resistant, NVP-AUY922–sensitive cell lines lacked NAD(PH:quinone oxidoreductase 1 (NQO1 enzyme and activity. However, colorectal LoVo cells still responded to both drugs in spite of having undetectable levels and activity of NQO1. Pharmacological and biologic inhibition of NQO1 did not confer resistance to 17-AAG in sensitive cell lines. Therefore, even though 17-AAG sensitivity is related to NQO1 protein levels and enzymatic activity, the absence of NQO1 does not necessarily convey resistance to 17-AAG in these cellular models. Moreover, NVP-AUY922 does not require NQO1 for its action and is a more potent inhibitor than 17-AAG in these cells. More importantly, we show in this report that NVP-AUY922 potentiates the inhibitory effects of chemotherapeutic agents, such as gemcitabine or oxaliplatin, and other drugs that are currently being evaluated in clinical trials as antitumor agents.

  16. Mutagen sensitivity: a genetic predisposition factor for cancer.

    Science.gov (United States)

    Wu, Xifeng; Gu, Jian; Spitz, Margaret R

    2007-04-15

    Mutagen sensitivity, measured by quantifying the chromatid breaks induced by mutagens in short-term cultures of peripheral blood lymphocytes, has been used as an indirect measure of DNA repair capacity. Numerous epidemiologic studies have suggested that mutagen sensitivity is a cancer susceptibility factor for a variety of epithelial cancers. A recent classic twin study examined systematically the role of genetic and environmental factors on the mutagen sensitivity phenotype and provided compelling evidence that mutagen sensitivity is highly heritable. A new prospective analysis provides further support to the notion that mutagen sensitivity increases the risk of cancer. In this review, we briefly summarize nearly two decades of epidemiologic and genetic studies linking mutagen sensitivity and cancer risk. The evidence is becoming increasingly convincing that mutagen sensitivity is a risk factor for cancer development.

  17. Ionizing radiation induces stemness in cancer cells.

    Directory of Open Access Journals (Sweden)

    Laura Ghisolfi

    Full Text Available The cancer stem cell (CSC model posits the presence of a small number of CSCs in the heterogeneous cancer cell population that are ultimately responsible for tumor initiation, as well as cancer recurrence and metastasis. CSCs have been isolated from a variety of human cancers and are able to generate a hierarchical and heterogeneous cancer cell population. CSCs are also resistant to conventional chemo- and radio-therapies. Here we report that ionizing radiation can induce stem cell-like properties in heterogeneous cancer cells. Exposure of non-stem cancer cells to ionizing radiation enhanced spherogenesis, and this was accompanied by upregulation of the pluripotency genes Sox2 and Oct3/4. Knockdown of Sox2 or Oct3/4 inhibited radiation-induced spherogenesis and increased cellular sensitivity to radiation. These data demonstrate that ionizing radiation can activate stemness pathways in heterogeneous cancer cells, resulting in the enrichment of a CSC subpopulation with higher resistance to radiotherapy.

  18. Highly Sensitive Marker Panel for Guidance in Lung Cancer Rapid Diagnostic Units

    Science.gov (United States)

    Blanco-Prieto, Sonia; De Chiara, Loretta; Rodríguez-Girondo, Mar; Vázquez-Iglesias, Lorena; Rodríguez-Berrocal, Francisco Javier; Fernández-Villar, Alberto; Botana-Rial, María Isabel; de la Cadena, María Páez

    2017-01-01

    While evidence for lung cancer screening implementation in Europe is awaited, Rapid Diagnostic Units have been established in many hospitals to accelerate the early diagnosis of lung cancer. We seek to develop an algorithm to detect lung cancer in a symptomatic population attending such unit, based on a sensitive serum marker panel. Serum concentrations of Epidermal Growth Factor, sCD26, Calprotectin, Matrix Metalloproteinases −1, −7, −9, CEA and CYFRA 21.1 were determined in 140 patients with respiratory symptoms (lung cancer and controls with/without benign pathology). Logistic Lasso regression was performed to derive a lung cancer prediction model, and the resulting algorithm was tested in a validation set. A classification rule based on EGF, sCD26, Calprotectin and CEA was established, able to reasonably discriminate lung cancer with 97% sensitivity and 43% specificity in the training set, and 91.7% sensitivity and 45.4% specificity in the validation set. Overall, the panel identified with high sensitivity stage I non-small cell lung cancer (94.7%) and 100% small-cell lung cancers. Our study provides a sensitive 4-marker classification algorithm for lung cancer detection to aid in the management of suspicious lung cancer patients in the context of Rapid Diagnostic Units. PMID:28117344

  19. Sensitization of radiation-induced cell death by genistein

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Tae Rim; Kim, In Gyu [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2010-03-15

    A number of epidemiological studies as well as biological experiments, showed that genistein, one of the isoflavone, prevents prostate cancer occurrence. In this study, we showed that genistein inhibited the cell proliferation of human promyeoltic leukemia HL-60 cells and induced G2/M phase arrest. In addition, combination of genistein treatment and {gamma}-irradiation displayed synergistic effect in apoptotic cell death of HL-60 cells. This means that the repair of genistein-induced DNA damage was hindered by {gamma}-irradiation and thus cell death was increased. In conclusion, genistein is one of the important chemicals that sensitize radiation-induced cell death.

  20. NBM-T-BMX-OS01, an Osthole Derivative, Sensitizes Human Lung Cancer A549 Cells to Cisplatin through AMPK-Dependent Inhibition of ERK and Akt Pathway

    Directory of Open Access Journals (Sweden)

    Tian-Jun Chen

    2015-06-01

    Full Text Available Background: Drug combination therapies using cisplatin and natural products are common practice in the treatment of human lung cancer. Osthole is a natural compound extracted from a number of medicinal plants and has been shown to exert strong anticancer activities with low toxicity. Methods: In the present study, NBM-T-BMX-OS01 (BMX, derived from the semi-synthesis of osthole, was evaluated in cisplatin treated A549 cells to investigate its effect on cisplatin resistance in human lung cancer. The anticancer effect of BMX were measured by cell viablity‚ colony formation‚ TUNEL staining‚ flow cytometry and cell cycle assay. The fluorescence staining was performed to detect intracellular and mitochondrial reactive oxygen species (ROS generation. Western blot analysis, antagonists pretreatment and small interfering RNA (siRNA transfection were used to determine the potential mechanism. Results: It was found that, in comparison with single cisplatin treatment, the combination of BMX and cisplatin resulted in greater efficacy in inhibition of proliferation and colony formation, apoptosis induction and cell cycle arrest. The results of fluorescence staining showed that the combination effect of BMX and cisplatin was due to oxidative stress induced by mitochondrial ROS generation. In addition, BMX significantly attenuated the phosphorylation of ERK and Akt, two important pro-survival kinases. In contrast, BMX inhibited the activation of AMPK, and knockdown of AMPK using specific siRNA partially reversed BMX-induced inhibition of ERK and Akt, as well as its synthetic effects on cisplatin induced anticancer activity in A549 cells. Conclusion: Taken together, this study provides that BMX might modulate cisplatin resistance through AMPK-ERK and AMPK-Akt pathways. These results also support the role of BMX as a potential drug candidate for use in combination with cisplatin in the treatment of human lung cancer.

  1. A novel autophagy/mitophagy inhibitor liensinine sensitizes breast cancer cells to chemotherapy through DNM1L-mediated mitochondrial fission.

    Science.gov (United States)

    Zhou, Jing; Li, Guobing; Zheng, Yi; Shen, Han-Ming; Hu, Xiaoye; Ming, Qian-Liang; Huang, Cheng; Li, Peng; Gao, Ning

    2015-01-01

    Autophagy inhibition has been widely accepted as a promising therapeutic strategy in cancer, while the lack of effective and specific autophagy inhibitors hinders its application. Here we found that liensinine, a major isoquinoline alkaloid, inhibits late-stage autophagy/mitophagy through blocking autophagosome-lysosome fusion. This effect is likely achieved via inhibiting the recruitment of RAB7A to lysosomes but not to autophagosomes. We further investigated the effects of autophagy inhibition by liensinine on the therapeutic efficacy of chemotherapeutic drugs and found that cotreatment of liensinine markedly decreased the viability and increased apoptosis in breast cancer cells treated with various chemotherapeutic agents. Mechanistically, we found that inhibition of autophagy/mitophagy by liensinine enhanced doxorubicin-mediated apoptosis by triggering mitochondrial fission, which resulted from dephosphorylation and mitochondrial translocation of DNM1L. However, blocking autophagosome/mitophagosome formation by pharmacological or genetic approaches markedly attenuated mitochondrial fission and apoptosis in cells with combinatatorial treatment. Moreover, liensinine was synergized with doxorubicin to inhibit tumor growth in MDA-MB-231 xenograft in vivo. Our findings suggest that liensinine could potentially be further developed as a novel autophagy/mitophagy inhibitor, and a combination of liensinine with classical chemotherapeutic drugs could represent a novel therapeutic strategy for treatment of breast cancer.

  2. Influence of vitamin D on cisplatin sensitivity in testicular germ cell cancer-derived cell lines and in a NTera2 xenograft model

    DEFF Research Database (Denmark)

    Jørgensen, Anne; Blomberg Jensen, Martin; Nielsen, John Erik;

    2013-01-01

    cisplatin, which may have clinical relevance. Given the pro-differentiation effect of vitamin D recently demonstrated in testicular germ cell tumors (TGCTs), we hypothesized that 1,25(OH)(2)D(3) could be a beneficial adjunctive to existing chemotherapy regime used to treat these tumors. In this study, cell...... survival effects of 1,25(OH)(2)D(3), another pro-differentiation compound, retinoic acid and cisplatin were investigated in TGCT-derived cell lines in vitro. 1,25(OH)(2)D(3) augmented the effect of cisplatin in an embryonal carcinoma-derived cell line (NTera2), possibly through downregulation......), and cisplatin were subsequently tested in vivo, in a NTera2 xenograft tumor model in nude mice. In xenograft tumors, co-treatment with 1,25(OH)(2)D(3) and cisplatin resulted in downregulation of OCT4 and simultaneous upregulation of p21 and p73, but did not reduce tumor growth significantly more than cisplatin...

  3. Inhibition of Notch1 increases paclitaxel sensitivity to human breast cancer

    Institute of Scientific and Technical Information of China (English)

    Zhao Li; Ma Yongjie; Gu Feng; Fu Li

    2014-01-01

    Background Paclitaxel (PAC) is the first-line chemotherapy drug for most breast cancer patients,but clinical studies showed that some breast cancer patients were insensitive to PAC,which led to chemotherapy failure.It was reported that Notch1 signaling participated in drug resistance of breast cancer.Here,we show whether Notch1 expression is related to PAC sensitivity of breast cancer.Methods We employed Notch1 siRNA and Notch1 inhibitor,N-[N-(3,5-difluorophenacetyl)-1-alanyl]-S-phenylglycine t-butylester (DAPT),to down regulate Notch1 expression in human breast cancer cells MDA-MB-231,and detected the inhibition effect by Western blotting and reverse trans cription-polymerase chain reaction,respectively.After 24 hours exposure to different concentration of PAC (0,1,5,10,15,20,and 25 μg/ml),the viability of the control group and experimental group cells was tested by MTT.We also examined the expression of Notch1 in PAC sensitive and nonsensitive breast cancer patients,respectively by immunohistochemistry (IHC).The PAC sensitivity of breast cancer patients were identified by collagen gel droplet embedded culture-drug sensitivity test (CD-DST).Results Down regulation of Notch1 expression by Notch1siRNA interference or Notch1 inhibitor increased the PAC sensitivity in MDA-MB-231 cells (P <0.05).Also,the expression of Notch1 in PAC sensitive patients was much lower than that of PAC non-sensitive patients (P <0.01).Conclusion Notch1 expression has an effect on PAC sensitivity in breast cancer patients,and the inhibition of Notch1 increases paclitaxel sensitivity to human breast cancer.

  4. [Development of ultrasonic cancer therapy using ultrasound sensitive liposome].

    Science.gov (United States)

    Suzuki, Ryo; Oda, Yusuke; Utoguchi, Naoki; Maruyama, Kazuo

    2010-12-01

    Ultrasound (US) has been utilized as a useful tool for diagnosis and therapy. US mediated drug and gene delivery is paid to attention as a non-invasive system. The combination of US and microbubbles generated microjet stream by inducing disruption of bubbles and resulted in enhancing permeability of cell membrane. This phenomenon has been utilized as driving force for drug and gene delivery. Recently, we developed ultrasound sensitive liposome [Bubble liposome (BL)] containing perfluoropropane gas. US combined with BL could effectively transfer gene in vivo compared to conventional cationic liposomes. Using this method, we succeeded to obtain a therapeutic effect in cancer gene therapy with Interleukin-12 corded plasmid DNA. Therefore, it is expected that US combined with BL might be a useful non-viral vector system. From this result, the fusion of liposomal and ultrasound technologies would be important for establishment of advanced cancer therapy.

  5. Over-expression of small ubiquitin-like modifier proteases 1 predicts chemo-sensitivity and poor survival in non-small cell lung cancer

    Institute of Scientific and Technical Information of China (English)

    Mu Juwei; Zuo Yong; Yang Wenjing; Chen Zhaoli; Liu Ziyuan; Tu Jun; Li Yan

    2014-01-01

    Background Non-small cell lung cancer (NSCLC) is one of the most common malignant tumors.Despite the advances in therapy over the years,its mortality remains high.The aim of this study was to evaluate the expression of small ubiquitin-like modifier (SUMO) proteases 1 (SENP1) in NSCLC tissues and its role in the regulation of vascular endothelial growth factor (VEGF) expression.We also investigated the association between the expression level of SENP1 and the clinicopathological features and survival of the patients.Methods A SENP1 small interfering RNA (siRNA) was constructed and transfected into the NSCLC cells.VEGF gene expression was analyzed by real-time polymerase chain reaction (RT-PCR).Immunohistochemistry staining was used to assess the expression of SENP1 in 100 NSCLC patients and its association with the clinicopathological features and survival was analyzed.Results VEGF expression was significantly higher in NSCLC tissues than in normal lung tissues.Inhibition of SENP1 by siRNA was associated with decreased VEGF expression.SENP1 was over-expressed in 55 of the 100 NSCLC samples (55%) and was associated with a moderate and low histological tumor grade (3.6%,38.2%,and 58.2% in high,moderate and low differentiated tumors,respectively,P=0.046),higher T stage (10.9% in T1,and 89.1% in T2 and T3 tumor samples,P <0.001)and TNM stage (10.9% in stage Ⅰ,and 89.1% in stages Ⅱ and Ⅲ tumor samples,P <0.001).The rate of lymph node metastasis was significantly higher in the SENP1 over-expression group (76.4%) than that in the SENP1 low expression group (33.3%,P <0.001).Sixty three patients received postoperative chemotherapy,including 34 with SENP1 over-expression and 29 with SENP1 low expression.Among the 34 patients with SENP1 over-expression,22 (64.7%) patients developed recurrence or metastasis,significantly higher than those in the low expression group 27.6% (8/29) (P=0.005).Multivariate Cox regression analysis showed that lymph

  6. Differential pathway dependency discovery associated with drug response across cancer cell lines. | Office of Cancer Genomics

    Science.gov (United States)

    The effort to personalize treatment plans for cancer patients involves the identification of drug treatments that can effectively target the disease while minimizing the likelihood of adverse reactions. In this study, the gene-expression profile of 810 cancer cell lines and their response data to 368 small molecules from the Cancer Therapeutics Research Portal (CTRP) are analyzed to identify pathways with significant rewiring between genes, or differential gene dependency, between sensitive and non-sensitive cell lines.

  7. Laryngeal cancer stem cells

    Directory of Open Access Journals (Sweden)

    Antonio Greco

    2016-03-01

    Full Text Available Laryngeal squamous cell carcinoma (LSCC is one of the most commonly diagnosed malignancies in the head and neck region with an increased incidence rate worldwide. Cancer stem cells (CSCs are a group of cells with eternal life or infinite self-renewal ability, which have high migrating, infiltrative, and metastatic abilities. Though CSCs only account for a small proportion in tumors, the high resistance to traditional therapy exempts them from therapy killing and thus they can reconstruct tumors. Our current knowledge, about CSCs in the LSCC, largely depends on head and neck studies with a lack of systematic data about the evidences of CSCs in tumorigenesis of LSCC. Certainly, the combination of therapies aimed at debulking the tumour (e.g. surgery, conventional chemotherapy, radiotherapy together with targeted therapies aimed at the elimination of the CSCs might have a positive impact on the long-term outcome of patients with laryngeal cancer (LC in the future and may cast a new light on the cancer treatment.

  8. Induction of cancer cell stemness by chemotherapy.

    Science.gov (United States)

    Hu, Xingwang; Ghisolfi, Laura; Keates, Andrew C; Zhang, Jian; Xiang, Shuanglin; Lee, Dong-ki; Li, Chiang J

    2012-07-15

    Recent studies indicate that cancer stem cells (CSCs) exist in most hematological and solid tumors. CSCs are characterized by their ability to self-renew and their capacity to differentiate into the multitude of cells that comprise the tumor mass. Moreover, these cells have been shown to be intrinsically resistant to conventional anticancer therapies. Despite their fundamental role in cancer pathogenesis, the cellular origin of CSCs remains highly controversial. The aim of this study was to examine whether heterogeneous cancer cells can acquire stem cell-like properties in response to chemotherapy. We demonstrate that carboplatin can induce the self-renewal (spherogenesis) and pluripotency (Sox2 and Oct3/4 expression) of hepatocellular carcinoma (HCC) cells grown under stem cell culture conditions. Moreover, we show that non-CSC cells, obtained by side population flow cytometric sorting using Hoechst 33342, can acquire stem-like properties after exposure to carboplatin. Finally, we show that knockdown of Sox2 and Oct3/4 gene expression in HCC cells can reduce carboplatin-mediated increases in sphere formation and increase cellular sensitivity to chemotherapy. Taken together, our data indicate that bulk cancer cells may be an important source of CSCs during tumor development, and that targeting Sox2 and/or Oct3/4 may be a promising approach for targeting CSCs in clinical cancer treatment.

  9. Dye-sensitized solar cells based on purple corn sensitizers

    Science.gov (United States)

    Phinjaturus, Kawin; Maiaugree, Wasan; Suriharn, Bhalang; Pimanpaeng, Samuk; Amornkitbamrung, Vittaya; Swatsitang, Ekaphan

    2016-09-01

    Natural dye extracted from husk, cob and silk of purple corn, were used for the first time as photosensitizers in dye sensitized solar cells (DSSCs). The dye sensitized solar cells fabrication process has been optimized in terms of solvent extraction. The resulting maximal efficiency of 1.06% was obtained from purple corn husk extracted by acetone. The ultraviolet-visible (UV-vis) spectroscopy, Fourier transform infrared spectroscopy (FTIR), electrochemical impedance spectroscopy (EIS) and incident photon-to-current efficiency (IPCE) were employed to characterize the natural dye and the DSSCs.

  10. FXR agonists enhance the sensitivity of biliary tract cancer cells to cisplatin via SHP dependent inhibition of Bcl-xL expression

    Science.gov (United States)

    Wang, Wei; Zhan, Ming; Li, Qi; Chen, Wei; Chu, Huiling; Huang, Qihong; Hou, Zhaoyuan; Man, Mohan; Wang, Jian

    2016-01-01

    Chemoresistance is common in patients with biliary tract cancer (BTC) including gallbladder cancer (GBC) and cholangiocarcinoma (CC). Therefore, it is necessary to identify effective chemotherapeutic agents for BTC. In the present study, we for the first time tested the effect of farnesoid X receptor (FXR) agonists GW4064 and CDCA (chenodeoxycholic acid) in combination with cisplatin (CDDP) on increasing the chemosensitivity in BTC. Our results show that co-treatment of CDDP with FXR agonists remarkably enhance chemosensitivity of BTC cells. Mechanistically, we found that activation of FXR induced expression of small heterodimer partner (SHP), which in turn inhibited signal transducer and activator of transcription 3 (STAT3) phosphorylation and resulted in down-regulation of Bcl-xL expression in BTC cells, leading to increased susceptibility to CDDP. Moreover, the experiments on tumor-bearing mice showed that GW4064/CDDP co-treatment inhibited the tumor growth in vivo by up-regulating SHP expression and down-regulating STAT3 phosphorylation. These results suggest CDDP in combination with FXR agonists could be a potential new therapeutic strategy for BTC. PMID:27127878

  11. Lauric acid can improve the sensitization of Cetuximab in KRAS/BRAF mutated colorectal cancer cells by retrievable microRNA-378 expression.

    Science.gov (United States)

    Weng, Wen-Hui; Leung, Wai-Hung; Pang, Yeu-Jye; Hsu, Hsi-Hsien

    2016-01-01

    EGFR-inhibitor (Cetuximab) is one of the main targeted drugs used for metastatic colorectal carcinoma (CRC). The benefit from Cetuximab appears to be limited to a subtype of patients, not for the patients with tumors harboring mutated BRAF or KRAS genes; unfortunately, it accounts for ~40-50% of CRC cases. Previous studies have connected higher expression levels of miR-378 to be commonly presented in patients without BRAF or KRAS mutants than in mutated CRCs. The microRNA-378 (miR-378) is coexpressed with PGC-1β and can be easily induced by fatty acid, for example lauric acid. Therefore, we hypothesized that elevation of miR-378 expression in mutated CRCs may stimulate the cell response to Cetuximab. Herein, seven CRC cell lines with confirmed mutation status were involved in two parallel experiments; directly in vitro transfected miR-378 mimics, and using lauric acid to indirectly induce the level of miR-378 in cells. After the increase of miR-378 in cells by either direct or indirect approaches, sensitivity to Cetuximab was restored in all BRAF mutants (p-value lauric acid approach. In conclusion, the present study demonstrated that lauric acid may efficiently induce miR-378 expression in CRC mutants, and both BRAF and a subtype of KRAS mutants presented significantly improved sensitivity to Cetuximab. Notably, BRAF mutants could even be inhibited in cell proliferation after elevated concentration of miR-378 in cells without combining with targeted therapy. This new approach may shed new light on BRAF or KRAS mutation in CRC patients for clinical trial, since lauric acid may easily be obtain from natural food, and it is supposed to be harmless to the cardiovascular system.

  12. Sanazole as a sensitizer of hypoxic cells with radical radiation in the treatment of advanced cancer of cervix an Indian experience.

    Science.gov (United States)

    Huilgol, Nagraj G; Dobrowsky, Werner; Tatsuzaki, Hideo; Chatterjee, Neela A; Kagiya, V T; Das, Kaushik

    2002-06-01

    AK-2123, is a nitrotriazole with a potential to sensitize hypoxic tissue to radiation. Cancer of cervix in advanced stages are predominantly treated with radiation. These are the tumours which harbour a large hypoxic core. This is an Indian experience of the multicentric trial. Patients were randomized to control and AK-2123 arm. 49 patients were randomized to each group. Patients received external radiation with telecobalt to a dose of 50 Gy in five weeks. Those in the study arm received 600 mg/m2, on alternate days. The patients were further treated with intracavitory radiation a dose of 20 Gy. The total dose of 70 Gy was achieved. Patients in the study arm had a complete response of 71.43% (35 of 49) while only 21 of 49 (42.86%) responded in the control group. The overall survival at two years was 72.2% for the study group and 32.43% for control. Neuropathy, a drug related toxicity was transient except, in one patient, which has persisted. AK-2123, has shown significant radiation sensitizing potential.

  13. A new prospect in cancer therapy: targeting cancer stem cells to eradicate cancer

    Institute of Scientific and Technical Information of China (English)

    Li-Sha Chen; An-Xin Wang; Bing Dong; Ke-Feng Pu; Li-Hua Yuan; Yi-Min Zhu

    2012-01-01

    According to the cancer stem cell theory,cancers can be initiated by cancer stem cells.This makes cancer stem cells prime targets for therapeutic intervention.Eradicating cancer stem cells by efficient targeting agents may have the potential to cure cancer.In this review,we summarize recent breakthroughs that have improved our understanding of cancer stem cells,and we discuss the therapeutic strategy of targeting cancer stem cells,a promising future direction for cancer stem cell research.

  14. Treatment Options for Renal Cell Cancer

    Science.gov (United States)

    ... cell cancer is a disease in which malignant (cancer) cells form in tubules of the kidney. Renal cell ... diagnosed, tests are done to find out if cancer cells have spread within the kidney or to other ...

  15. General Information about Renal Cell Cancer

    Science.gov (United States)

    ... cell cancer is a disease in which malignant (cancer) cells form in tubules of the kidney. Renal cell ... diagnosed, tests are done to find out if cancer cells have spread within the kidney or to other ...

  16. Treatment Option Overview (Renal Cell Cancer)

    Science.gov (United States)

    ... cell cancer is a disease in which malignant (cancer) cells form in tubules of the kidney. Renal cell ... diagnosed, tests are done to find out if cancer cells have spread within the kidney or to other ...

  17. Lung cancer - non-small cell

    Science.gov (United States)

    Cancer - lung - non-small cell; Non-small cell lung cancer; NSCLC; Adenocarcinoma - lung; Squamous cell carcinoma - lung ... Research shows that smoking marijuana may help cancer cells grow. But there is no direct link between ...

  18. CXCR4 Inhibition with AMD3100 Sensitizes Prostate Cancer to Docetaxel Chemotherapy

    Directory of Open Access Journals (Sweden)

    Urszula M. Domanska

    2012-08-01

    Full Text Available Several in vitro and in vivo models have revealed the key role of CXCR4/CXCL12 axis in tumor-stroma interactions. Stromal cells present in the tumor microenvironment express high levels of CXCL12 protein, directly stimulating proliferation and migration of CXCR4-expressing cancer cells. This specific prosurvival influence of stromal cells on tumor cells is thought to protect them from cytotoxic chemotherapy and is postulated as a possible explanation for the minimal residual disease in hematological and solid cancers. Therefore, CXCR4/CXCL12 signaling is an attractive therapeutic target in cancer, as proven in preclinical leukemia mouse models, where CXCR4 inhibition sensitized cancer cells to conventional chemotherapy. This study investigates whether inhibition of CXCR4 with the specific inhibitor AMD3100 sensitizes human prostate cancer cells to docetaxel. We showed that both mouse and human stromal cell lines have a protective effect on PC3-luc cells by promoting their survival after chemotherapy. Furthermore, we demonstrated that AMD3100 sensitizes PC3-luc cells to docetaxel. In a subcutaneous xenograft mouse model of human prostate carcinoma, we showed that a combination of docetaxel and AMD3100 exerts increased antitumor effect compared with docetaxel alone. We concluded that CXCR4 inhibition chemosensitizes prostate cancer cells, both in vitro and in vivo. To explore the relevance of these findings, we analyzed CXCR4 expression levels in human prostate cancer samples. We found that cancer cells present in bone metastatic lesions express higher CXCR4 levels relative to the cells present in primary tumors and lymph node metastatic lesions. These findings underscore the potential of CXCR4 inhibitors as chemosensitizing agents.

  19. Carboplatin treatment of antiestrogen-resistant breast cancer cells

    DEFF Research Database (Denmark)

    Larsen, Mathilde S; Yde, Christina Westmose; Christensen, Ib J

    2012-01-01

    Antiestrogen resistance is a major clinical problem in current breast cancer treatment. Therefore, biomarkers and new treatment options for antiestrogen-resistant breast cancer are needed. In this study, we investigated whether antiestrogen‑resistant breast cancer cell lines have increased...... sensitivity to carboplatin, as it was previously shown with cisplatin, and whether low Bcl-2 expression levels have a potential value as marker for increased carboplatin sensitivity. Breast cancer cells resistant to the pure antiestrogen fulvestrant, and two out of four cell lines resistant...... to the antiestrogen tamoxifen, were more sensitive to carboplatin treatment compared to the parental MCF-7 cell line. This indicates that carboplatin may be an advantageous treatment in antiestrogen‑resistant breast cancer; however, a marker for increased sensitivity would be needed. Low Bcl-2 expression...

  20. Hepatocyte SLAMF3 reduced specifically the multidrugs resistance protein MRP-1 and increases HCC cells sensitization to anti-cancer drugs.

    Science.gov (United States)

    Fouquet, Grégory; Debuysscher, Véronique; Ouled-Haddou, Hakim; Eugenio, Mélanie Simoes; Demey, Baptiste; Singh, Amrathlal Rabbind; Ossart, Christèle; Al Bagami, Mohammed; Regimbeau, Jean-Marc; Nguyen-Khac, Eric; Naassila, Mickael; Marcq, Ingrid; Bouhlal, Hicham

    2016-05-31

    Multidrug resistance MDR proteins (MRPs) are members of the C family of a group of proteins named ATP binding cassette (ABC) transporters. MRPs can transport drugs including anticancer drugs, nucleoside analogs, antimetabolites and tyrosine kinase inhibitors. Drugs used in HCC therapy, such as tyrosine kinase inhibitor sorafenib, are substrates of uptake and/or efflux transporters. Variable expression of MRPs at the plasma membrane of tumor cells may contribute to drug resistance and subsequent clinical response. Recently, we reported that the hepatocyte SLAMF3 expression (Signaling Lymphocytic Activation Molecule Family member 3) was reduced in tumor cells from hepatocellular carcinoma (HCC) compared to its high expression in adjacent tissues. In the present study, we make a strong correlation between induced SLAMF3 overexpression and the specific loss of MRP-1 expression and its functionalities as a drugs resistance transporter. No changes were observed on expression of ABCG2 and MDR. More importantly, we highlight a strong inverse correlation between MRP-1 and SLAMF3 expression in patients with HCC. We propose that the SLAMF3 overexpression in cancerous cells could represent a potential therapeutic strategy to improve the drugs sensibility of resistant cells and thus control the therapeutic failure in HCC patients.

  1. Elevated pressure, a novel cancer therapeutic tool for sensitizing cisplatin-mediated apoptosis in A549

    Energy Technology Data Exchange (ETDEWEB)

    Oh, Sangnam [Cellular and Developmental Biology, Division of Biomedical Science, College of Medicine, Korea University, Seoul 136-705 (Korea, Republic of); Department of Preventive Medicine and Medical Research Center for Environmental Toxico-Genomics and Proteomics, College of Medicine, Korea University, Seoul 136-705 (Korea, Republic of); Kim, Yanghee [Department of Preventive Medicine and Medical Research Center for Environmental Toxico-Genomics and Proteomics, College of Medicine, Korea University, Seoul 136-705 (Korea, Republic of); Kim, Joonhee [Cellular and Developmental Biology, Division of Biomedical Science, College of Medicine, Korea University, Seoul 136-705 (Korea, Republic of); Department of Preventive Medicine and Medical Research Center for Environmental Toxico-Genomics and Proteomics, College of Medicine, Korea University, Seoul 136-705 (Korea, Republic of); Kwon, Daeho [Department of Preventive Medicine and Medical Research Center for Environmental Toxico-Genomics and Proteomics, College of Medicine, Korea University, Seoul 136-705 (Korea, Republic of); Lee, Eunil, E-mail: eunil@korea.ac.kr [Cellular and Developmental Biology, Division of Biomedical Science, College of Medicine, Korea University, Seoul 136-705 (Korea, Republic of); Department of Preventive Medicine and Medical Research Center for Environmental Toxico-Genomics and Proteomics, College of Medicine, Korea University, Seoul 136-705 (Korea, Republic of)

    2010-08-13

    Research highlights: {yields} Sensitized apoptosis in cancer cells stimulated by EP precondition with p53 dependence. {yields} EP attenuates several CDDP-resistance mechanisms. {yields} No harmful effect of EP on normal fibroblasts. -- Abstract: Intensive cancer therapy strategies have thus far focused on sensitizing cancer cells to anticancer drug-mediated apoptosis to overcome drug resistance, and this strategy has led to more effective cancer therapeutics. Cisplatin (cis-diamminedichloroplatinum(II), CDDP) is an effective anticancer drug used to treat many types of cancer, including non-small cell lung carcinoma (NSCLC), and can be used in combination with various chemicals to enhance cancer cell apoptosis. Here, we introduce the use of elevated pressure (EP) in combination with CDDP for cancer treatment and explore the effects of EP on CDDP-mediated apoptosis in NSCLC cells. Our findings demonstrate that preconditioning NSCLC cells with EP sensitizes cells for CDDP-induced apoptosis. Enhanced apoptosis was dependent on p53 and HO-1 expression, and was associated with increased DNA damage and down-regulation of genes involved in nucleotide excision repair. The transcriptional levels of transporter proteins indicated that the mechanism by which EP-induced CDDP sensitization was intracellular drug accumulation. The protein levels of some antioxidants, such as hemeoxygenase-1 (HO-1), glutathione (GSH) and glutathione peroxidase (Gpx), were decreased in A549 cells exposed to EP via the down-regulation of the transcription factor nuclear factor (erythroid-derived 2)-like 2 (Nrf-2). Furthermore, normal human fibroblasts were resistant to EP treatment, with no elevated DNA damage or apoptosis. Collectively, these data show that administration of EP is a potential adjuvant tool for CDDP-based chemosensitivity of lung cancer cells that may reduce drug resistance.

  2. Primary cultures of human colon cancer as a model to study cancer stem cells.

    Science.gov (United States)

    Koshkin, Sergey; Danilova, Anna; Raskin, Grigory; Petrov, Nikolai; Bajenova, Olga; O'Brien, Stephen J; Tomilin, Alexey; Tolkunova, Elena

    2016-09-01

    The principal cause of death in cancer involves tumor progression and metastasis. Since only a small proportion of the primary tumor cells, cancer stem cells (CSCs), which are the most aggressive, have the capacity to metastasize and display properties of stem cells, it is imperative to characterize the gene expression of diagnostic markers and to evaluate the drug sensitivity in the CSCs themselves. Here, we have examined the key genes that are involved in the progression of colorectal cancer and are expressed in cancer stem cells. Primary cultures of colorectal cancer cells from a patient's tumors were studied using the flow cytometry and cytological methods. We have evaluated the clinical and stem cell marker expression in these cells, their resistance to 5-fluorouracil and irinotecan, and the ability of cells to form tumors in mice. The data shows the role of stem cell marker Oct4 in the resistance of primary colorectal cancer tumor cells to 5-fluorouracil.

  3. Diagnostic sensitivity of ¹⁸fluorodeoxyglucose positron emission tomography for detecting synchronous multiple primary cancers in head and neck cancer patients.

    Science.gov (United States)

    Kondo, Norio; Tsukuda, Mamoru; Nishimura, Goshi

    2012-05-01

    We assessed the sensitivity of positron emission tomography (PET) for detecting synchronous multiple primary cancers, particularly synchronous esophageal cancers in head and neck cancer patients. We retrospectively reviewed 230 head and neck cancer patients. All the patients routinely underwent the following examinations: urinalysis, occult blood, tumor marker detection [squamous cell carcinoma (SCC), cytokeratin fragment (CYFRA), and carcinoembryonic antigen (CEA)], esophagogastroduodenoscopy, colonoscopy (when CEA was high or occult blood was positive), abdominal ultrasonography, plain chest computed tomography (CT), and PET. Bronchoscopy was performed when CT revealed lung shadow of central region. Synchronous multiple primary cancers were detected in 42 (18.2%) patients. The diagnostic sensitivity of PET for synchronous primary cancers was as follows: esophagus, 7.6% (1/13); stomach, 25.0% (2/8); lung, 66.7% (4/6); head and neck, 75.0% (3/4); colon, 0% (0/1); kidney, 0% (0/1); and subcutaneous, 100% (1/1). The sensitivity of PET for detecting synchronous esophageal cancers is low because these are early-stage cancers (almost stage 0-I). Therefore, it is necessary to perform esophagogastroduodenoscopy for detecting synchronous esophageal cancers. PET is an important additional tool for detecting synchronous multiple primary cancers because the diagnostic sensitivity of PET in synchronous head and neck cancer and lung cancer is high. But PET has the limitation of sensitivity for synchronous multiple primary cancers because the diagnostic sensitivity of PET in synchronous esophageal cancer is very low.

  4. Monitoring of epidermal growth factor receptor tyrosine kinase inhibitor-sensitizing and resistance mutations in the plasma DNA of patients with advanced non-small cell lung cancer during treatment with erlotinib

    DEFF Research Database (Denmark)

    Sorensen, Boe S; Wu, Lin; Wei, Wen;

    2014-01-01

    BACKGROUND: The feasibility of monitoring epidermal growth factor receptor (EGFR) mutations in plasma DNA from patients with advanced non-small cell lung cancer (NSCLC) during treatment with erlotinib and its relation to disease progression was investigated. METHODS: The amount of EGFR-mutant DNA...... was tested in plasma DNA from patients with advanced NSCLC with allele-specific polymerase chain reaction assays. Blood samples from 23 patients with adenocarcinoma of NSCLC that carried tyrosine kinase inhibitor-sensitizing EGFR mutations were taken immediately before treatment with erlotinib. Additional...... blood samples were taken at timed intervals until erlotinib treatment was withdrawn. RESULTS: The amount of plasma DNA with sensitizing EGFR mutations was found to be reduced after the first cycle of erlotinib treatment in 22 of 23 patients (96%). No patients presented with the resistant T790M mutation...

  5. [SIRT1 Influences the Sensitivity of A549 Non-small Cell Lung Cancer Cell Line to 
Cisplatin via Modulating the Noxa Expression].

    Science.gov (United States)

    Cao, Bin; He, Xiaofeng; Wang, Wengong; Shi, Minke

    2016-02-01

    背景与目的 非小细胞肺癌的顺铂耐药是常见的临床现象,严重制约了患者的化疗效果,是亟待解决的问题。SIRT1和Noxa的表达变化影响肿瘤细胞对化疗药物的敏感性。本研究旨在研究SIRT1表达对非小细胞肺癌对顺铂的敏感性的影响,并探讨其涉及Noxa表达的机制,以求为提高非小细胞肺癌细胞对顺铂敏感性提供希望。方法 利用实时荧光定量PCR和Western blot分析A549细胞及顺铂耐药的A549/DDP细胞SIRT1及Noxa mRNA和蛋白水平的表达差异。利用siRNA干扰技术抑制A549/DDP细胞的SIRT1表达,进而使用Cell Titer Blue试验、流式细胞术从细胞增殖、细胞周期和细胞凋亡方面分析SIRT1沉默对A549/DPP细胞顺铂敏感性的影响。同时利用实时荧光定量PCR和Western blot分析SIRT1抑制对A549/DPP细胞Noxa表达的影响。结果 A549细胞和A549/DDP细胞对顺铂的敏感性有显著差异,与A549细胞相比,A549/DDP细胞的SIRT1表达较高,但Noxa表达较低。使用siRNA抑制A549/DPP细胞的SIRT1表达后,与未抑制SIRT1细胞相比,4 μg/mL顺铂处理后的细胞存活率降低,G2期/M期阻滞比例增加,凋亡率提高。同时,SIRT1沉默导致A549/DPP细胞的Noxa表达增加。结论 较高的SIRT1可能引起A549细胞对顺铂的耐药性,抑制SIRT1可以提高A549/DDP细胞对顺铂的敏感性,其机制可能涉及SIRT1对Noxa的调节。.

  6. Metal-Free Sensitizers for Dye-Sensitized Solar Cells.

    Science.gov (United States)

    Chaurasia, Sumit; Lin, Jiann T

    2016-06-01

    This review focuses on our work on metal-free sensitizers for dye-sensitized solar cells (DSSCs). Sensitizers based on D-A'-π-A architecture (D is a donor, A is an acceptor, A' is an electron-deficient entity) exhibit better light harvesting than D-π-A-type sensitizers. However, appropriate molecular design is needed to avoid excessive aggregation of negative charge at the electron-deficient entity upon photoexcitation. Rigidified aromatics, including aromatic segments comprising fused electron-excessive and -deficient units in the spacer, allow effective electronic communication, and good photoinduced charge transfer leads to excellent cell performance. Sensitizers with two anchors/acceptors, D(-π-A)2 , can more efficiently harvest light, inject electrons, and suppress dark current compared with congeners with a single anchor. Appropriate incorporation of heteroaromatic units in the spacer is beneficial to DSSC performance. High-performance, aqueous-based DSSCs can be achieved with a dual redox couple comprising imidazolium iodide and 2,2,6,6-tetramethylpiperidin-N-oxyl, and/or using dyes of improved wettability through the incorporation of a triethylene oxide methyl ether chain.

  7. IAP antagonists sensitize murine osteosarcoma cells to killing by TNFα

    Science.gov (United States)

    Shekhar, Tanmay M.; Miles, Mark A.; Gupte, Ankita; Taylor, Scott; Tascone, Brianna; Walkley, Carl R.; Hawkins, Christine J.

    2016-01-01

    Outcomes for patients diagnosed with the bone cancer osteosarcoma have not improved significantly in the last four decades. Only around 60% of patients and about a quarter of those with metastatic disease survive for more than five years. Although DNA-damaging chemotherapy drugs can be effective, they can provoke serious or fatal adverse effects including cardiotoxicity and therapy-related cancers. Better and safer treatments are therefore needed. We investigated the anti-osteosarcoma activity of IAP antagonists (also known as Smac mimetics) using cells from primary and metastatic osteosarcomas that arose spontaneously in mice engineered to lack p53 and Rb expression in osteoblast-derived cells. The IAP antagonists SM-164, GDC-0152 and LCL161, which efficiently target XIAP and cIAPs, sensitized cells from most osteosarcomas to killing by low levels of TNFα but not TRAIL. RIPK1 expression levels and activity correlated with sensitivity. RIPK3 levels varied considerably between tumors and RIPK3 was not required for IAP antagonism to sensitize osteosarcoma cells to TNFα. IAP antagonists, including SM-164, lacked mutagenic activity. These data suggest that drugs targeting XIAP and cIAP1/2 may be effective for osteosarcoma patients whose tumors express abundant RIPK1 and contain high levels of TNFα, and would be unlikely to provoke therapy-induced cancers in osteosarcoma survivors. PMID:27129149

  8. Development of Nanoparticle Sensitized Solar Cells

    OpenAIRE

    2013-01-01

    In this thesis, I have been working with the development of nanoparticle sensitized solar cells. In the subarea of quantum dot sensitized solar cells (QDSCs), I have investigated type-II quantum dots (QDs), quantum rods (QRs) and alloy QDs, and developed novel redox couples as electrolytes. I have also proposed upconversion nanoparticles as energy relay materials for dye-sensitized solar cells (DSCs). Colloidal ZnSe/CdS type-II QDs were applied for QDSCs for the first time. The interesting fe...

  9. Spectrofluorometric determination of intracellular levels of reactive oxygen species in drug-sensitive and drug-resistant cancer cells using the 2‧,7‧-dichlorofluorescein diacetate assay

    Science.gov (United States)

    Loetchutinat, Chatchanok; Kothan, Suchart; Dechsupa, Samarn; Meesungnoen, Jintana; Jay-Gerin, Jean-Paul; Mankhetkorn, Samlee

    2005-02-01

    This article examines a non-invasive spectrofluorometric method using the 2',7'-dichlorofluorescein diacetate (DCHF-DA) assay for quantifying the intracellular reactive oxygen species (ROS i) produced in four cultured cancer cell lines: drug-sensitive (K562) and drug-resistant (K562/ adr) human erythromyelogenous leukemia cell lines, and drug-sensitive (GLC4) and drug-resistant (GLC4/ adr) human small cell lung carcinoma cell lines. The oxidation of the probe to the fluorescent dichlorofluorescein (DCF) was continuously monitored by following the DCF fluorescence intensity as a function of time using a standard spectrofluorometer in the presence of an extracellular DCF fluorescence quencher (Co 2+). By fitting the spectrofluorometric data to a kinetic model based on the following two reactions: (i) deacetylation of DCHF-DA to the oxidant-sensitive compound 2',7'-dichlorofluorescein (DCHF) by cellular esterase enzymes (pseudo-first-order rate constant: ke) and (ii) oxidation of DCHF by ROS i (second-order rate constant: k2), the parameters intervening in DCF formation, ke and the product of k2 by the ROS i concentration, were quantitatively determined for the different cell lines studied. The results revealed that the intracellular esterase content or activity is similar in K562, K562/ adr, and GLC4 cells, but 5-fold higher in GLC4/ adr cells. The product k2[ROS i] was found to be similar in the four cell lines considered, with a mean value of (5.3±0.9)×10 -7 cell -1 s -1. Assuming that H 2O 2 (in combination with peroxidases) is the primary responsible species for DCHF oxidation in intact cells, and using the rate constant value k2=790±62 M s established in our laboratory for the reaction of DCHF with H 2O 2 in the presence of horseradish peroxidase, the mean value of the intracellular levels of ROS i in those cells was estimated to be 0.67±0.16 nM per cell. Such a value compares favorably to H 2O 2 intracellular steady-state concentrations that have been

  10. Defining Therapy for Recurrent Platinum-sensitive Ovarian Cancer

    Science.gov (United States)

    In this phase III clinical trial, women with platinum-sensitive, recurrent ovarian epithelial, fallopian tube, or primary peritoneal cancer will be randomly assigned to undergo secondary cytoreductive surgery, if they are candidates for such surgery, and

  11. Dye-sensitized solar cells based on purple corn sensitizers

    Energy Technology Data Exchange (ETDEWEB)

    Phinjaturus, Kawin [Materials Science and Nanotechnology Program, Faculty of Science, Khon Kaen University, Khon Kaen 40002 (Thailand); Maiaugree, Wasan [Department of Physics, Faculty of Science, Khon Kaen University, Khon Kaen 40002 (Thailand); Suriharn, Bhalang [Department of Plant Science and Agricultural Resources, Faculty of Agriculture, Khon Kaen University, Khon Kaen 40002 (Thailand); Pimanpaeng, Samuk; Amornkitbamrung, Vittaya [Department of Physics, Faculty of Science, Khon Kaen University, Khon Kaen 40002 (Thailand); Integrated Nanotechnology Research Center (INRC), Department of Physics, Faculty of Science, Khon Kaen University, Khon Kaen 40002 (Thailand); Swatsitang, Ekaphan, E-mail: ekaphan@kku.ac.th [Department of Physics, Faculty of Science, Khon Kaen University, Khon Kaen 40002 (Thailand); Integrated Nanotechnology Research Center (INRC), Department of Physics, Faculty of Science, Khon Kaen University, Khon Kaen 40002 (Thailand); Nanotec-KKU Center of Excellence on Advanced Nanomaterials for Energy Production and Storage, Khon Kaen 40002 (Thailand)

    2016-09-01

    Graphical abstract: - Highlights: • Extract from husk, cob and silk of purple corn was used as a photosensitizer in DSSC. • Effect of solvents i.e. acetone, ethanol and DI water on DSSC efficiency was studied. • The highest efficiency of 1.06% was obtained in DSSC based on acetone extraction. - Abstract: Natural dye extracted from husk, cob and silk of purple corn, were used for the first time as photosensitizers in dye sensitized solar cells (DSSCs). The dye sensitized solar cells fabrication process has been optimized in terms of solvent extraction. The resulting maximal efficiency of 1.06% was obtained from purple corn husk extracted by acetone. The ultraviolet–visible (UV–vis) spectroscopy, Fourier transform infrared spectroscopy (FTIR), electrochemical impedance spectroscopy (EIS) and incident photon-to-current efficiency (IPCE) were employed to characterize the natural dye and the DSSCs.

  12. Potential Roles of Amiloride-Sensitive Sodium Channels in Cancer Development

    Directory of Open Access Journals (Sweden)

    Siguang Xu

    2016-01-01

    Full Text Available The ENaC/degenerin ion channel superfamily includes the amiloride-sensitive epithelial sodium channel (ENaC and acid sensitive ionic channel (ASIC. ENaC is a multimeric ion channel formed by heteromultimeric membrane glycoproteins, which participate in a multitude of biological processes by mediating the transport of sodium (Na+ across epithelial tissues such as the kidney, lungs, bladder, and gut. Aberrant ENaC functions contribute to several human disease states including pseudohypoaldosteronism, Liddle syndrome, cystic fibrosis, and salt-sensitive hypertension. Increasing evidence suggests that ion channels not only regulate ion homeostasis and electric signaling in excitable cells but also play important roles in cancer cell behaviors such as proliferation, apoptosis, invasion, and migration. Indeed, ENaCs/ASICs had been reported to be associated with cancer characteristics. Given their cell surface localization and pharmacology, pharmacological strategies to target ENaC/ASIC family members may be promising cancer therapeutics.

  13. Cancer stem cell markers in common cancers - therapeutic implications

    DEFF Research Database (Denmark)

    Klonisch, Thomas; Wiechec, Emilia; Hombach-Klonisch, Sabine

    2008-01-01

    Rapid advance in the cancer stem cell field warrants optimism for the development of more reliable cancer therapies within the next 2-3 decades. Below, we characterize and compare the specific markers that are present on stem cells, cancer cells and cancer stem cells (CSC) in selected tissues...

  14. Multitask learning improves prediction of cancer drug sensitivity

    Science.gov (United States)

    Yuan, Han; Paskov, Ivan; Paskov, Hristo; González, Alvaro J.; Leslie, Christina S.

    2016-01-01

    Precision oncology seeks to predict the best therapeutic option for individual patients based on the molecular characteristics of their tumors. To assess the preclinical feasibility of drug sensitivity prediction, several studies have measured drug responses for cytotoxic and targeted therapies across large collections of genomically and transcriptomically characterized cancer cell lines and trained predictive models using standard methods like elastic net regression. Here we use existing drug response data sets to demonstrate that multitask learning across drugs strongly improves the accuracy and interpretability of drug prediction models. Our method uses trace norm regularization with a highly efficient ADMM (alternating direction method of multipliers) optimization algorithm that readily scales to large data sets. We anticipate that our approach will enhance efforts to exploit growing drug response compendia in order to advance personalized therapy. PMID:27550087

  15. Metabolic alterations in cancer cells and therapeutic implications

    Institute of Scientific and Technical Information of China (English)

    Naima Hammoudi; Kausar Begam Riaz Ahmed; Celia Garcia-Prieto; Peng Huang

    2011-01-01

    Cancer metabolism has emerged as an important area of research in recent years. Elucidation of the metabolic differences between cancer and normal cells and the underlying mechanisms will not only advance our understanding of fundamental cancer cell biology but also provide an important basis for the development of new therapeutic strategies and novel compounds to selectively eliminate cancer cells by targeting their unique metabolism. This article reviews several important metabolic alterations in cancer cells, with an emphasis on increased aerobic glycolysis (the Warburg effect) and glutamine addiction, and discusses the mechanisms that may contribute to such metabolic changes. In addition, metabolic alterations in cancer stem cells, mitochondrial metabolism and its influence on drug sensitivity, and potential therapeutic strategies and agents that target cancer metabolism are also discussed.

  16. Unique proteomic signature for radiation sensitive patients; a comparative study between normo-sensitive and radiation sensitive breast cancer patients

    Energy Technology Data Exchange (ETDEWEB)

    Skiöld, Sara [Center for Radiation Protection Research, Department of Molecular Biosciences, The Wernner-Gren Institute, Stockholm University, Stockholm (Sweden); Azimzadeh, Omid [Institute of Radiation Biology, German Research Center for Environmental Health, Helmholtz Zentrum München (Germany); Merl-Pham, Juliane [Research Unit Protein Science, German Research Center for Environmental Health, Helmholtz Zentrum München, Neuherberg (Germany); Naslund, Ingemar; Wersall, Peter; Lidbrink, Elisabet [Division of Radiotherapy, Radiumhemmet, Karolinska University Hospital, Stockholm (Sweden); Tapio, Soile [Institute of Radiation Biology, German Research Center for Environmental Health, Helmholtz Zentrum München (Germany); Harms-Ringdahl, Mats [Center for Radiation Protection Research, Department of Molecular Biosciences, The Wernner-Gren Institute, Stockholm University, Stockholm (Sweden); Haghdoost, Siamak, E-mail: Siamak.Haghdoost@su.se [Center for Radiation Protection Research, Department of Molecular Biosciences, The Wernner-Gren Institute, Stockholm University, Stockholm (Sweden)

    2015-06-15

    Highlights: • The unique protein expression profiles were found that separate radiosensitive from normal sensitive breast cancer patients. • The oxidative stress response, coagulation properties and acute phase response suggested to be the hallmarks of radiation sensitivity. - Abstract: Radiation therapy is a cornerstone of modern cancer treatment. Understanding the mechanisms behind normal tissue sensitivity is essential in order to minimize adverse side effects and yet to prevent local cancer reoccurrence. The aim of this study was to identify biomarkers of radiation sensitivity to enable personalized cancer treatment. To investigate the mechanisms behind radiation sensitivity a pilot study was made where eight radiation-sensitive and nine normo-sensitive patients were selected from a cohort of 2914 breast cancer patients, based on acute tissue reactions after radiation therapy. Whole blood was sampled and irradiated in vitro with 0, 1, or 150 mGy followed by 3 h incubation at 37 °C. The leukocytes of the two groups were isolated, pooled and protein expression profiles were investigated using isotope-coded protein labeling method (ICPL). First, leukocytes from the in vitro irradiated whole blood from normo-sensitive and extremely sensitive patients were compared to the non-irradiated controls. To validate this first study a second ICPL analysis comparing only the non-irradiated samples was conducted. Both approaches showed unique proteomic signatures separating the two groups at the basal level and after doses of 1 and 150 mGy. Pathway analyses of both proteomic approaches suggest that oxidative stress response, coagulation properties and acute phase response are hallmarks of radiation sensitivity supporting our previous study on oxidative stress response. This investigation provides unique characteristics of radiation sensitivity essential for individualized radiation therapy.

  17. Redefining Hormone Sensitive Disease in Advanced Prostate Cancer

    Directory of Open Access Journals (Sweden)

    Xiaoyu Hou

    2012-01-01

    Full Text Available Prostate cancer is the most common cancer among men in the United States. For decades, the cornerstone of medical treatment for advanced prostate cancer has been hormonal therapy, intended to lower testosterone levels, known as Androgen Deprivation Therapy (ADT. The development of hormone-resistant prostate cancer (now termed castration-resistant prostate cancer:CRPC remains the key roadblock in successful long-term management of prostate cancer. New advancements in medical therapy for prostate cancer have added to the hormonal therapy armamentarium. These new therapeutic agents not only provide a survival benefit but also show potential for reversing hormonal resistance in metastatic CRPC, and thus redefining hormonally sensitive disease.

  18. PRB介导子宫内膜癌细胞对MPA敏感性的作用机制研究%Mechanism study of PRB in regulating therapeutic sensitivity of MPA in endometrial cancer cells

    Institute of Scientific and Technical Information of China (English)

    王晶; 孙笑; 王丽华; 王玉东

    2014-01-01

    Aim To explore the role of progesterone re-ceptor B ( PRB ) in regulation of medroxyprogesterone acetate ( MPA) sensitivity in endometrial cancer cells, and to investigate the effect of MPA on the biological character in Ishikawa cells infected with shRNA targe-ting PRB gene. Methods Ishikawa cells were stably transfected with PRB shRNA using lentivirus to knock-down endogenous PRB expression. Real-time fluores-cent quantitative PCR was applied to confirm the knockdown effect. MTT assay, flow cytometry and cell invasion assay were applied to detect the influence of MPA on endometrial cancer cell proliferation, apopto-sis and invasion. We also used Western blot assay to detect the effect of MPA induced the activation of ERK/MAPK signal pathway. Results Recombinant lentiviral vector expressing shRNA targeting PRB gene was successfully established, results of real-time PCR and Western blot showed that compared with control group, PRB expression in Ishikawa cells infected with shRNA decreased obviously ( P <0.01 ); MPA could repress endometrial cancer cells proliferation and inva-sion, meanwhile promoted its apoptosis ( P <0.01 ) . However, the effect was almost reverse in Ishikawa cells infected with shRNA. Furthermore, MPA induced ERK/MAPK activation in Ishikawa cells infected with shRNA. Conclusions PRB plays a role in regulating therapeutic sensitivity of MPA in endometrial cancer cells;and for Ishikawa cells infected with shRNA tar-geting PRB gene, MPA has effects on the biological character via pERK1/2-MAPK signal pathway.%目的:明确孕激素受体B ( PRB)介导子宫内膜癌细胞对醋酸甲羟孕酮( MPA)的敏感性,及观察干扰 PRB表达,MPA对内膜癌细胞生物学行为的影响。方法利用慢病毒载体系统转染对孕激素敏感的 Ishikawa 细胞,干扰 PRB表达,实时荧光定量PCR ( qPCR)及Western blot检测Ish-ikawa细胞PRB的mRNA和蛋白水平。 MTT法、流式细胞技术( FACS)、Transwell法分别检测MPA对内膜癌细

  19. Androgen receptor and its splice variant, AR-V7, differentially regulate FOXA1 sensitive genes in LNCaP prostate cancer cells.

    Science.gov (United States)

    Krause, William C; Shafi, Ayesha A; Nakka, Manjula; Weigel, Nancy L

    2014-09-01

    Prostate cancer (PCa) is an androgen-dependent disease, and tumors that are resistant to androgen ablation therapy often remain androgen receptor (AR) dependent. Among the contributors to castration-resistant PCa are AR splice variants that lack the ligand-binding domain (LBD). Instead, they have small amounts of unique sequence derived from cryptic exons or from out of frame translation. The AR-V7 (or AR3) variant is constitutively active and is expressed under conditions consistent with CRPC. AR-V7 is reported to regulate a transcriptional program that is similar but not identical to that of AR. However, it is unknown whether these differences are due to the unique sequence in AR-V7, or simply to loss of the LBD. To examine transcriptional regulation by AR-V7, we have used lentiviruses encoding AR-V7 (amino acids 1-627 of AR with the 16 amino acids unique to the variant) to prepare a derivative of the androgen-dependent LNCaP cells with inducible expression of AR-V7. An additional cell line was generated with regulated expression of AR-NTD (amino acids 1-660 of AR); this mutant lacks the LBD but does not have the AR-V7 specific sequence. We find that AR and AR-V7 have distinct activities on target genes that are co-regulated by FOXA1. Transcripts regulated by AR-V7 were similarly regulated by AR-NTD, indicating that loss of the LBD is sufficient for the observed differences. Differential regulation of target genes correlates with preferential recruitment of AR or AR-V7 to specific cis-regulatory DNA sequences providing an explanation for some of the observed differences in target gene regulation.

  20. Cancer stem cells in human gastrointestinal cancer.

    Science.gov (United States)

    Taniguchi, Hiroaki; Moriya, Chiharu; Igarashi, Hisayoshi; Saitoh, Anri; Yamamoto, Hiroyuki; Adachi, Yasushi; Imai, Kohzoh

    2016-11-01

    Cancer stem cells (CSCs) are thought to be responsible for tumor initiation, drug and radiation resistance, invasive growth, metastasis, and tumor relapse, which are the main causes of cancer-related deaths. Gastrointestinal cancers are the most common malignancies and still the most frequent cause of cancer-related mortality worldwide. Because gastrointestinal CSCs are also thought to be resistant to conventional therapies, an effective and novel cancer treatment is imperative. The first reported CSCs in a gastrointestinal tumor were found in colorectal cancer in 2007. Subsequently, CSCs were reported in other gastrointestinal cancers, such as esophagus, stomach, liver, and pancreas. Specific phenotypes could be used to distinguish CSCs from non-CSCs. For example, gastrointestinal CSCs express unique surface markers, exist in a side-population fraction, show high aldehyde dehydrogenase-1 activity, form tumorspheres when cultured in non-adherent conditions, and demonstrate high tumorigenic potential in immunocompromised mice. The signal transduction pathways in gastrointestinal CSCs are similar to those involved in normal embryonic development. Moreover, CSCs are modified by the aberrant expression of several microRNAs. Thus, it is very difficult to target gastrointestinal CSCs. This review focuses on the current research on gastrointestinal CSCs and future strategies to abolish the gastrointestinal CSC phenotype.

  1. Novel proteasome inhibitor ixazomib sensitizes neuroblastoma cells to doxorubicin treatment

    Science.gov (United States)

    Li, Haoyu; Chen, Zhenghu; Hu, Ting; Wang, Long; Yu, Yang; Zhao, Yanling; Sun, Wenijing; Guan, Shan; Pang, Jonathan C.; Woodfield, Sarah E.; Liu, Qing; Yang, Jianhua

    2016-01-01

    Neuroblastoma (NB) is the most common extracranial malignant solid tumor seen in children and continues to lead to the death of many pediatric cancer patients. The poor outcome in high risk NB is largely attributed to the development of chemoresistant tumor cells. Doxorubicin (dox) has been widely employed as a potent anti-cancer agent in chemotherapeutic regimens; however, it also leads to chemoresistance in many cancer types including NB. Thus, developing novel small molecules that can overcome dox-induced chemoresistance is a promising strategy in cancer therapy. Here we show that the second generation proteasome inhibitor ixazomib (MLN9708) not only inhibits NB cell proliferation and induces apoptosis in vitro but also enhances dox-induced cytotoxicity in NB cells. Ixazomib inhibits dox-induced NF-κB activity and sensitizes NB cells to dox-induced apoptosis. More importantly, ixazomib demonstrated potent anti-tumor efficacy in vivo by enhancing dox-induced apoptosis in an orthotopic xenograft NB mouse model. Collectively, our study illustrates the anti-tumor efficacy of ixazomib in NB both alone and in combination with dox, suggesting that combination therapy including ixazomib with traditional therapeutic agents such as dox is a viable strategy that may achieve better outcomes for NB patients. PMID:27687684

  2. A case-control study of wood dust exposure, mutagen sensitivity, and lung cancer risk.

    Science.gov (United States)

    Wu, X; Delclos, G L; Annegers, J F; Bondy, M L; Honn, S E; Henry, B; Hsu, T C; Spitz, M R

    1995-09-01

    The associations between lung cancer risk, mutagen sensitivity (a marker of cancer susceptibility), and a putative lung carcinogen, wood dust, were assessed in a hospital-based case-control study. There were 113 African -American and 67 Mexican-American cases with newly diagnosed, previously untreated lung cancer and 270 controls, frequency-matched on age, ethnicity, and sex. Mutagen sensitivity ( 1 chromatid break/cell after short-term bleomycin treatment) was associated with statistically significant elevated risk for lung cancer [odds ration (OR) = 4.3; 95% confidence intervals (CI) = 2.3-7.9]. Wood dust exposure was also a significant predictor of risk (overall OR = 3.5; CI = 1.4-8.6) after controlling for smoking and mutagen sensitivity. When stratified by ethnicity, wood dust exposure was s significant risk factor for African-Americans (OR = 5.5; CI = 1.6-18.9) but not for Mexican-Americans (OR = 2.0; CI = 0.5-8.1). The ORs were 3.8 and 4.8 for non-small cell lung cancer in Mexican-Americans (CI = 1.2-18.5). Stratified analysis suggested evidence of strong interactions between wood dust exposure and both mutagen sensitivity and smoking in lung cancer risk.

  3. Overcoming cisplatin resistance of ovarian cancer cells by targeting HIF-1-regulated cancer metabolism.

    Science.gov (United States)

    Ai, Zhihong; Lu, Yang; Qiu, Songbo; Fan, Zhen

    2016-04-01

    Cisplatin is currently one of the most effective chemotherapeutic drugs used for treating ovarian cancer; however, resistance to cisplatin is common. In this study, we explored an experimental strategy for overcoming cisplatin resistance of human ovarian cancer from the new perspective of cancer cell metabolism. By using two pairs of genetically matched cisplatin-sensitive and cisplatin-resistant ovarian cancer cell lines, we tested the hypothesis that downregulating hypoxia-inducible factor-1 (HIF-1), which regulates metabolic enzymes involved in glycolysis, is a promising strategy for overcoming cisplatin resistance of human ovarian cancer cells. We found that cisplatin downregulated the level of the regulatable α subunit of HIF-1, HIF-1α, in cisplatin-sensitive ovarian cancer cells through enhancing HIF-1α degradation but did not downregulate HIF-1α in their cisplatin-resistant counterparts. Overexpression of a degradation-resistant HIF-1α (HIF-1α ΔODD) reduced cisplatin-induced apoptosis in cisplatin-sensitive cells, whereas genetic knockdown of HIF-1α or pharmacological promotion of HIF-1α degradation enhanced response to cisplatin in both cisplatin-sensitive and cisplatin-resistant ovarian cancer cells. We further demonstrated that knockdown of HIF-1α improved the response of cisplatin-resistant ovarian cancer cells to cisplatin by redirecting the aerobic glycolysis in the resistant cancer cells toward mitochondrial oxidative phosphorylation, leading to cell death through overproduction of reactive oxygen species. Our findings suggest that the HIF-1α-regulated cancer metabolism pathway could be a novel target for overcoming cisplatin resistance in ovarian cancer.

  4. General Information about Small Cell Lung Cancer

    Science.gov (United States)

    ... lung cancer is a disease in which malignant (cancer) cells form in the tissues of the lung. The ... diagnosed, tests are done to find out if cancer cells have spread within the chest or to other ...

  5. Treatment Option Overview (Small Cell Lung Cancer)

    Science.gov (United States)

    ... lung cancer is a disease in which malignant (cancer) cells form in the tissues of the lung. The ... diagnosed, tests are done to find out if cancer cells have spread within the chest or to other ...

  6. Stages of Small Cell Lung Cancer

    Science.gov (United States)

    ... lung cancer is a disease in which malignant (cancer) cells form in the tissues of the lung. The ... diagnosed, tests are done to find out if cancer cells have spread within the chest or to other ...

  7. Ki-67 is required for maintenance of cancer stem cells but not cell proliferation

    Science.gov (United States)

    Cidado, Justin; Wong, Hong Yuen; Rosen, D. Marc; Cimino-Mathews, Ashley; Garay, Joseph P.; Fessler, Abigail G.; Rasheed, Zeshaan A.; Hicks, Jessica; Cochran, Rory L.; Croessmann, Sarah; Zabransky, Daniel J.; Mohseni, Morassa; Beaver, Julia A.; Chu, David; Cravero, Karen; Christenson, Eric S.; Medford, Arielle; Mattox, Austin; De Marzo, Angelo M.; Argani, Pedram; Chawla, Ajay; Hurley, Paula J.; Lauring, Josh; Park, Ben Ho

    2016-01-01

    Ki-67 expression is correlated with cell proliferation and is a prognostic marker for various cancers; however, its function is unknown. Here we demonstrate that genetic disruption of Ki-67 in human epithelial breast and colon cancer cells depletes the cancer stem cell niche. Ki-67 null cells had a proliferative disadvantage compared to wildtype controls in colony formation assays and displayed increased sensitivity to various chemotherapies. Ki-67 null cancer cells showed decreased and delayed tumor formation in xenograft assays, which was associated with a reduction in cancer stem cell markers. Immunohistochemical analyses of human breast cancers revealed that Ki-67 expression is maintained at equivalent or greater levels in metastatic sites of disease compared to matched primary tumors, suggesting that maintenance of Ki-67 expression is associated with metastatic/clonogenic potential. These results elucidate Ki-67's role in maintaining the cancer stem cell niche, which has potential diagnostic and therapeutic implications for human malignancies. PMID:26823390

  8. ELF5 suppresses estrogen sensitivity and underpins the acquisition of antiestrogen resistance in luminal breast cancer.

    Directory of Open Access Journals (Sweden)

    Maria Kalyuga

    Full Text Available We have previously shown that during pregnancy the E-twenty-six (ETS transcription factor ELF5 directs the differentiation of mammary progenitor cells toward the estrogen receptor (ER-negative and milk producing cell lineage, raising the possibility that ELF5 may suppress the estrogen sensitivity of breast cancers. To test this we constructed inducible models of ELF5 expression in ER positive luminal breast cancer cells and interrogated them using transcript profiling and chromatin immunoprecipitation of DNA followed by DNA sequencing (ChIP-Seq. ELF5 suppressed ER and FOXA1 expression and broadly suppressed ER-driven patterns of gene expression including sets of genes distinguishing the luminal molecular subtype. Direct transcriptional targets of ELF5, which included FOXA1, EGFR, and MYC, accurately classified a large cohort of breast cancers into their intrinsic molecular subtypes, predicted ER status with high precision, and defined groups with differential prognosis. Knockdown of ELF5 in basal breast cancer cell lines suppressed basal patterns of gene expression and produced a shift in molecular subtype toward the claudin-low and normal-like groups. Luminal breast cancer cells that acquired resistance to the antiestrogen Tamoxifen showed greatly elevated levels of ELF5 and its transcriptional signature, and became dependent on ELF5 for proliferation, compared to the parental cells. Thus ELF5 provides a key transcriptional determinant of breast cancer molecular subtype by suppression of estrogen sensitivity in luminal breast cancer cells and promotion of basal characteristics in basal breast cancer cells, an action that may be utilised to acquire antiestrogen resistance.

  9. Sensitive-cell-based fish chromatophore biosensor

    Science.gov (United States)

    Plant, Thomas K.; Chaplen, Frank W.; Jovanovic, Goran; Kolodziej, Wojtek; Trempy, Janine E.; Willard, Corwin; Liburdy, James A.; Pence, Deborah V.; Paul, Brian K.

    2004-07-01

    A sensitive biosensor (cytosensor) has been developed based on color changes in the toxin-sensitive colored living cells of fish. These chromatophores are highly sensitive to the presence of many known and unknown toxins produced by microbial pathogens and undergo visible color changes in a dose-dependent manner. The chromatophores are immobilized and maintained in a viable state while potential pathogens multiply and fish cell-microbe interactions are monitored. Low power LED lighting is used to illuminate the chromatophores which are magnified using standard optical lenses and imaged onto a CCD array. Reaction to toxins is detected by observing changes is the total area of color in the cells. These fish chromatophores are quite sensitive to cholera toxin, Staphococcus alpha toxin, and Bordatella pertussis toxin. Numerous other toxic chemical and biological agents besides bacterial toxins also cause readily detectable color effects in chromatophores. The ability of the chromatophore cell-based biosensor to distinguish between different bacterial pathogens was examined. Toxin producing strains of Salmonella enteritis, Vibrio parahaemolyticus, and Bacillus cereus induced movement of pigmented organelles in the chromatophore cells and this movement was measured by changes in the optical density over time. Each bacterial pathogen elicited this measurable response in a distinctive and signature fashion. These results suggest a chromatophore cell-based biosensor assay may be applicable for the detection and identification of virulence activities associated with certain air-, food-, and water-borne bacterial pathogens.

  10. Therapeutic implications of colon cancer stem cells

    Institute of Scientific and Technical Information of China (English)

    Eros; Fabrizi; Simona; di; Martino; Federica; Pelacchi; Lucia; Ricci-Vitiani

    2010-01-01

    Colorectal cancer is the second most common cause of cancer-related death in many industrialized countries and is characterized by a heterogenic pool of cells with distinct differentiation patterns. Recently, the concept that cancer might arise from a rare population of cells with stem cell-like properties has received support with regard to several solid tumors, including colorectal cancer. According to the cancer stem cell hypothesis, cancer