WorldWideScience

Sample records for cancer cell sensitivity

  1. Albendazole sensitizes cancer cells to ionizing radiation

    International Nuclear Information System (INIS)

    Patel, Kirtesh; Doudican, Nicole A; Schiff, Peter B; Orlow, Seth J

    2011-01-01

    Brain metastases afflict approximately half of patients with metastatic melanoma (MM) and small cell lung cancer (SCLC) and represent the direct cause of death in 60 to 70% of those affected. Standard of care remains ineffective in both types of cancer with the challenge of overcoming the blood brain barrier (BBB) exacerbating the clinical problem. Our purpose is to determine and characterize the potential of albendazole (ABZ) as a cytotoxic and radiosensitizing agent against MM and SCLC cells. Here, ABZ's mechanism of action as a DNA damaging and microtubule disrupting agent is assessed through analysis of histone H2AX phosphorylation and cell cyle progression. The cytotoxicity of ABZ alone and in combination with radiation therapy is determined though clonogenic cell survival assays in a panel of MM and SCLC cell lines. We further establish ABZ's ability to act synergistically as a radio-sensitizer through combination index calculations and apoptotic measurements of poly (ADP-ribose) polymerase (PARP) cleavage. ABZ induces DNA damage as measured by increased H2AX phosphorylation. ABZ inhibits the growth of MM and SCLC at clinically achievable plasma concentrations. At these concentrations, ABZ arrests MM and SCLC cells in the G2/M phase of the cell cycle after 12 hours of treatment. Exploiting the notion that cells in the G2/M phase are the most sensitive to radiation therapy, we show that treatment of MM and SCLC cells treated with ABZ renders them more sensitive to radiation in a synergistic fashion. Additionally, MM and SCLC cells co-treated with ABZ and radiation exhibit increased apoptosis at 72 hours. Our study suggests that the orally available antihelminthic ABZ acts as a potent radiosensitizer in MM and SCLC cell lines. Further evaluation of ABZ in combination with radiation as a potential treatment for MM and SCLC brain metastases is warranted

  2. Albendazole sensitizes cancer cells to ionizing radiation

    Science.gov (United States)

    2011-01-01

    Background Brain metastases afflict approximately half of patients with metastatic melanoma (MM) and small cell lung cancer (SCLC) and represent the direct cause of death in 60 to 70% of those affected. Standard of care remains ineffective in both types of cancer with the challenge of overcoming the blood brain barrier (BBB) exacerbating the clinical problem. Our purpose is to determine and characterize the potential of albendazole (ABZ) as a cytotoxic and radiosensitizing agent against MM and SCLC cells. Methods Here, ABZ's mechanism of action as a DNA damaging and microtubule disrupting agent is assessed through analysis of histone H2AX phosphorylation and cell cyle progression. The cytotoxicity of ABZ alone and in combination with radiation therapy is determined though clonogenic cell survival assays in a panel of MM and SCLC cell lines. We further establish ABZ's ability to act synergistically as a radio-sensitizer through combination index calculations and apoptotic measurements of poly (ADP-ribose) polymerase (PARP) cleavage. Results ABZ induces DNA damage as measured by increased H2AX phosphorylation. ABZ inhibits the growth of MM and SCLC at clinically achievable plasma concentrations. At these concentrations, ABZ arrests MM and SCLC cells in the G2/M phase of the cell cycle after 12 hours of treatment. Exploiting the notion that cells in the G2/M phase are the most sensitive to radiation therapy, we show that treatment of MM and SCLC cells treated with ABZ renders them more sensitive to radiation in a synergistic fashion. Additionally, MM and SCLC cells co-treated with ABZ and radiation exhibit increased apoptosis at 72 hours. Conclusions Our study suggests that the orally available antihelminthic ABZ acts as a potent radiosensitizer in MM and SCLC cell lines. Further evaluation of ABZ in combination with radiation as a potential treatment for MM and SCLC brain metastases is warranted. PMID:22094106

  3. Radiation sensitivity of human lung cancer cell lines

    International Nuclear Information System (INIS)

    Carmichael, J.; Degraff, W.G.; Gamson, J.; Russo, G.; Mitchell, J.B.; Gazdar, A.F.; Minna, J.D.; Levitt, M.L.

    1989-01-01

    X-Ray survival curves were determined using a panel of 17 human lung cancer cell lines, with emphasis on non-small cell lung cancer (NSCLC). In contrast to classic small cell lung cancer (SCLC) cell lines, NSCLC cell lines were generally less sensitive to radiation as evidenced by higher radiation survival curve extrapolation numbers, surviving fraction values following a 2Gy dose (SF2) and the mean inactivation dose values (D) values. The spectrum of in vitro radiation responses observed was similar to that expected in clinical practice, although mesothelioma was unexpectedly sensitive in vitro. Differences in radiosensitivity were best distinguished by comparison of SF2 values. Some NSCLC lines were relatively sensitive, and in view of this demonstrable variability in radiation sensitivity, the SF2 value may be useful for in vitro predictive assay testing of clinical specimens. (author)

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

    International Nuclear Information System (INIS)

    Huang, Shang-Lang; Chao, Chuck C.-K.

    2015-01-01

    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. 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.

  6. Effect of troglitazone on radiation sensitivity in cervix cancer cells

    International Nuclear Information System (INIS)

    An, Zheng Zhe; Liu, Xian Guang; Song, Hye Jin; Choi, Chi Hwan; Kim, Won Dong; Park, Woo Yoon; Yu, Jae Ran

    2012-01-01

    Troglitazone (TRO) is a peroxisome proliferator-activated receptor γ (PPARγ ) agonist. TRO has antiproliferative activity on many kinds of cancer cells via G1 arrest. TRO also increases Cu 2+ /Zn 2+ -superoxide dismutase (CuZnSOD) and catalase. Cell cycle, and SOD and catalase may affect on radiation sensitivity. We investigated the effect of TRO on radiation sensitivity in cancer cells in vitro. Three human cervix cancer cell lines (HeLa, Me180, and SiHa) were used. The protein expressions of SOD and catalase, and catalase activities were measured at 2-10 μM of TRO for 24 hours. Cell cycle was evaluated with flow cytometry. Reactive oxygen species (ROS) was measured using 2',7'-dichlorofluorescin diacetate. Cell survival by radiation was measured with clonogenic assay. By 5 μM TRO for 24 hours, the mRNA, protein expression and activity of catalase were increased in all three cell lines. G0- G1 phase cells were increased in HeLa and Me180 by 5 μM TRO for 24 hours, but those were not increased in SiHa. By pretreatment with 5 μM TRO radiation sensitivity was increased in HeLa and Me180, but it was decreased in SiHa. In Me180, with 2 μM TRO which increased catalase but not increased G0-G1 cells, radiosensitization was not observed. ROS produced by radiation was decreased with TRO. TRO increases radiation sensitivity through G0-G1 arrest or decreases radiation sensitivity through catalasemediated ROS scavenging according to TRO dose or cell types. The change of radiation sensitivity by combined with TRO is not dependent on the PPAR γ expression level.

  7. Andrographolide sensitizes prostate cancer cells to TRAIL-induced apoptosis

    Directory of Open Access Journals (Sweden)

    Ruo-Jing Wei

    2018-01-01

    Full Text Available Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL is a promising agent for anticancer therapy. The identification of small molecules that can establish the sensitivity of prostate cancer (PCa cells to TRAIL-induced apoptosis is crucial for the targeted treatment of PCa. PC3, DU145, JAC-1, TsuPr1, and LNCaP cells were treated with Andrographolide (Andro and TRAIL, and the apoptosis was measured using the Annexin V/PI double staining method. Real time-polymerase chain reaction (PCR and Western blot analysis were performed to measure the expression levels of target molecules. RNA interference technique was used to down-regulate the expression of the target protein. We established a nude mouse xenograft model of PCa, which was used to measure the caspase-3 activity in the tumor cells using flow cytometry. In this research study, our results demonstrated that Andro preferentially increased the sensitivity of PCa cells to TRAIL-induced apoptosis at subtoxic concentrations, and the regulation mechanism was related to the up-regulation of DR4. In addition, it also increased the p53 expression and led to the generation of reactive oxygen species (ROS in the cells. Further research revealed that the DR4 inhibition, p53 expression, and ROS generation can significantly reduce the apoptosis induced by the combination of TRAIL and Andro in PCa cells. In conclusion, Andro increases the sensitivity of PCa cells to TRAIL-induced apoptosis through the generation of ROS and up-regulation of p53 and then promotes PCa cell apoptosis associated with the activation of DR4.

  8. 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.

  9. Inhibition of autophagy induced by TSA sensitizes colon cancer cell to radiation.

    Science.gov (United States)

    He, Gang; Wang, Yan; Pang, Xueli; Zhang, Bo

    2014-02-01

    Radiotherapy is one of the main treatments for clinical cancer therapy. However, its application was limited due to lack of radiosensitivity in some cancers. Trichostatin A (TSA) is a classic histone deacetylases inhibitor (HDACi) that specifically inhibits the biochemical functions of HDAC and is demonstrated to be an active anticancer drug. However, whether it could sensitize colon cancer to radiation is not clear. Our results showed that TSA enhanced the radiosensitivity of colon cancer cells as determined by CCK-8 and clonogenic survival assay. Moreover, apoptotic cell death induced by radiation was enhanced by TSA treatment. Additionally, TSA also induced autophagic response in colon cancer cells, while autophagy inhibition led to cell apoptosis and enhanced the radiosensitivity of colon cancer cells. Our data suggested that inhibition of cytoprotective autophagy sensitizes cancer cell to radiation, which might be further investigated for clinical cancer radiotherapy.

  10. Sensitivity of cancer cells to truncated diphtheria toxin.

    Directory of Open Access Journals (Sweden)

    Yi Zhang

    2010-05-01

    Full Text Available Diphtheria toxin (DT has been utilized as a prospective anti-cancer agent for the targeted delivery of cytotoxic therapy to otherwise untreatable neoplasia. DT is an extremely potent toxin for which the entry of a single molecule into a cell can be lethal. DT has been targeted to cancer cells by deleting the cell receptor-binding domain and combining the remaining catalytic portion with targeting proteins that selectively bind to the surface of cancer cells. It has been assumed that "receptorless" DT cannot bind to and kill cells. In the present study, we report that "receptorless" recombinant DT385 is in fact cytotoxic to a variety of cancer cell lines.In vitro cytotoxicity of DT385 was measured by cell proliferation, cell staining and apoptosis assays. For in vivo studies, the chick chorioallantoic membrane (CAM system was used to evaluate the effect of DT385 on angiogenesis. The CAM and mouse model system was used to evaluate the effect of DT385 on HEp3 and Lewis lung carcinoma (LLC tumor growth, respectively.Of 18 human cancer cell lines tested, 15 were affected by DT385 with IC(50 ranging from 0.12-2.8 microM. Furthermore, high concentrations of DT385 failed to affect growth arrested cells. The cellular toxicity of DT385 was due to the inhibition of protein synthesis and induction of apoptosis. In vivo, DT385 diminished angiogenesis and decreased tumor growth in the CAM system, and inhibited the subcutaneous growth of LLC tumors in mice.DT385 possesses anti-angiogenic and anti-tumor activity and may have potential as a therapeutic agent.

  11. 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.

  12. Paris Saponin I Sensitizes Gastric Cancer Cell Lines to Cisplatin via Cell Cycle Arrest and Apoptosis.

    Science.gov (United States)

    Song, Shuichuan; Du, Leiwen; Jiang, Hao; Zhu, Xinhai; Li, Jinhui; Xu, Ji

    2016-10-18

    BACKGROUND Dose-related toxicity is the major restriction of cisplatin and cisplatin-combination chemotherapy, and is a challenge for advanced gastric cancer treatment. We explored the possibility of using Paris saponin I as an agent to sensitize gastric cancer cells to cisplatin, and examined the underlying mechanism. MATERIAL AND METHODS Growth inhibition was detected by MTT assay. The cell cycle and apoptosis were detected using flow cytometry and Annexin V/PI staining. The P21waf1/cip1, Bcl-2, Bax, and caspase-3 protein expression were detected using Western blot analysis. RESULTS The results revealed that PSI sensitized gastric cancer cells to cisplatin, with low toxicity. The IC50 value of cisplatin in SGC-7901 cell lines was decreased when combined with PSI. PSI promoted cisplatin-induced G2/M phase arrest and apoptosis in a cisplatin concentration-dependent manner. Bcl-2 protein expression decreased, but Bax, caspase-3, and P21waf1/cip1 protein expression increased with PSI treatment. CONCLUSIONS The underlying mechanism of Paris saponin I may be related to targeting the apoptosis pathway and cell cycle blocking, which suggests that PSI is a potential therapeutic sensitizer for cisplatin in treating gastric cancer.

  13. 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

  14. Sensitivity of breast cancer cell lines to recombinant thiaminase I.

    Science.gov (United States)

    Liu, Shuqian; Monks, Noel R; Hanes, Jeremiah W; Begley, Tadhg P; Yu, Hui; Moscow, Jeffrey A

    2010-05-01

    We have previously shown that the expression of the thiamine transporter THTR2 is decreased sevenfold in breast cancer, which may leave breast cancer cells vulnerable to acute thiamine starvation. This concept was supported by the observation that MDA231 breast cancer xenografts demonstrated growth inhibition in mice fed a thiamine-free diet. We purified recombinant Bacillus thiaminolyticus thiaminase I enzyme, which digests thiamine, to study acute thiamine starvation in breast cancer. Thiaminase I enzyme was cytotoxic in six breast cancer cell lines with IC(50)s ranging from 0.012 to 0.022 U/ml. The growth inhibitory effects of the combination of thiaminase I with either doxorubicin or paclitaxel were also examined. Over a wide range of drug concentrations, thiaminase 1 was consistently synergistic or additive with doxorubicin and paclitaxel in MCF-7, ZR75, HS578T and T47D cell lines, with most combinations having a calculated combination index (CI) of less than 0.8, indicating synergy. Although thiaminase I exposure did not stimulate the energy-sensing signaling kinases AKT, AMPK and GSK-3beta in MCF-7, ZR75, HS578T and T47D cell lines, thiaminase I exposure did stimulate expression of the ER stress response protein GRP78. In summary, thiaminase I is cytotoxic in breast cancer cell lines and triggers the unfolded protein response. These findings suggest that THTR2 down-regulation in breast tumors may present a nutritional vulnerability that could be exploited by thiaminase I enzyme therapy.

  15. 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.

  16. PKC 412 sensitizes U1810 non-small cell lung cancer cells to DNA damage

    International Nuclear Information System (INIS)

    Hemstroem, Therese H.; Joseph, Bertrand; Schulte, Gunnar; Lewensohn, Rolf; Zhivotovsky, Boris

    2005-01-01

    Non-small cell lung carcinoma (NSCLC) is characterized by resistance to drug-induced apoptosis, which might explain the survival of lung cancer cells following treatment. Recently we have shown that the broad-range kinase inhibitor staurosporine (STS) reactivates the apoptotic machinery in U1810 NSCLC cells [Joseph et al., Oncogene 21 (2002) 65]. Lately, several STS analogs that are more specific in kinase inhibition have been suggested for tumor treatment. In this study the apoptosis-inducing ability of the STS analogs PKC 412 and Ro 31-8220 used alone or in combination with DNA-damaging agents in U1810 cells was investigated. In these cells Ro 31-8220 neither induced apoptosis when used alone, nor sensitized cells to etoposide treatment. PKC 412 as a single agent induced death of a small number of U1810 cells, whereas it efficiently triggered a dose- and time-dependent apoptosis in U1285 small cell lung carcinoma cells. In both cell types PKC 412 triggered release of mitochondrial proteins followed by caspase activation. However, concomitant activation of a caspase-independent pathway was essential to kill NSCLC cells. Importantly, PKC 412 was able to sensitize etoposide- and radiation-induced death of U1810 cells. The best sensitization was achieved when PKC 412 was administered 24 h after treatments. In U1810 cells, Ro 31-8220 decreased PMA-induced ERK phosphorylation as efficiently as PKC 412, indicating that the failure of Ro 31-8220 to induce apoptosis was not due to weaker inhibition of conventional and novel PKC isoforms. However, Ro 31-8220 increased the basal level of ERK and Akt phosphorylation in both cell lines, whereas Akt phosphorylation was suppressed in the U1810 cells, which might influence apoptosis. These results suggest that PKC 412 could be a useful tool in increasing the efficiency of therapy of NSCLC

  17. Inhibition of SRC-3 enhances sensitivity of human cancer cells to histone deacetylase inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Zou, Zhengzhi, E-mail: zouzhengzhi@m.scnu.edu.cn [MOE Key Laboratory of Laser Life Science and Institute of Laser Life Science, College of Biophotonics, South China Normal University, Guangzhou 510000 (China); Luo, Xiaoyong [Department of Oncology, The Affiliated Luoyang Central Hospital of Zhengzhou University, Luoyang 471000 (China); Nie, Peipei [KingMed Diagnostics and KingMed School of Laboratory Medicine, Guangzhou Medical University, Guangzhou 510000 (China); Wu, Baoyan; Zhang, Tao; Wei, Yanchun [MOE Key Laboratory of Laser Life Science and Institute of Laser Life Science, College of Biophotonics, South China Normal University, Guangzhou 510000 (China); Wang, Wenyi [Xiamen Cancer Center, Department of Medical Oncology, The First Affiliated Hospital of Xiamen University, Xiamen 361000 (China); Geng, Guojun; Jiang, Jie [Xiamen Cancer Center, Department of Thoracic Surgery, The First Affiliated Hospital of Xiamen University, Xiamen 361000 (China); Mi, Yanjun, E-mail: myjgj_77@163.com [Xiamen Cancer Center, Department of Medical Oncology, The First Affiliated Hospital of Xiamen University, Xiamen 361000 (China)

    2016-09-09

    SRC-3 is widely expressed in multiple tumor types and involved in cancer cell proliferation and apoptosis. Histone deacetylase (HDAC) inhibitors are promising antitumor drugs. However, the poor efficacy of HDAC inhibitors in solid tumors has restricted its further clinical application. Here, we reported the novel finding that depletion of SRC-3 enhanced sensitivity of breast and lung cancer cells to HDAC inhibitors (SAHA and romidepsin). In contrast, overexpression of SRC-3 decreased SAHA-induced cancer cell apoptosis. Furthermore, we found that SRC-3 inhibitor bufalin increased cancer cell apoptosis induced by HDAC inhibitors. The combination of bufalin and SAHA was particular efficient in attenuating AKT activation and reducing Bcl-2 levels. Taken together, these accumulating data might guide development of new breast and lung cancer therapies. - Highlights: • Depletion of SRC-3 enhanced sensitivity of breast and lung cancer cells to HDAC inhibitors. • Overexpression of SRC-3 enhanced cancer cell resistance to HDAC inhibitors. • SRC-3 inhibitor bufalin increased cancer cell apoptosis induced by HDAC inhibitors. • Bufalin synergized with HDAC inhibitor attenuated AKT activation and reduced Bcl-2 levels in human cancer cell.

  18. 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

    2017-04-01

    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. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  19. 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.

  20. Short-chain C6 ceramide sensitizes AT406-induced anti-pancreatic cancer cell activity

    International Nuclear Information System (INIS)

    Zhao, Xiaoguang; Sun, Baoyou; Zhang, Jingjing; Zhang, Ruishen; Zhang, Qing

    2016-01-01

    Our previous study has shown that AT406, a first-in-class small molecular antagonist of IAPs (inhibitor of apoptosis proteins), inhibits pancreatic cancer cell proliferation in vitro and in vivo. The aim of this research is to increase AT406's sensitivity by adding short-chain C6 ceramide. We show that co-treatment of C6 ceramide dramatically potentiated AT406-induced caspase/apoptosis activation and cytotoxicity in established (Panc-1 and Mia-PaCa-2 lines) and primary human pancreatic cancer cells. Reversely, caspase inhibitors largely attenuated C6 ceramide plus AT406-induced above cancer cell death. Molecularly, C6 ceramide downregulated Bcl-2 to increase AT406's sensitivity in pancreatic cancer cells. Intriguingly, C6 ceramide-mediated AT406 sensitization was nullified with Bcl-2 shRNA knockdown or pretreatment of the Bcl-2 inhibitor ABT-737. In vivo, liposomal C6 ceramide plus AT406 co-administration dramatically inhibited Panc-1 xenograft tumor growth in severe combined immunodeficient (SCID) mice. The combined anti-tumor activity was significantly more potent than either single treatment. Expressions of IAPs (cIAP1/XIAP) and Bcl-2 were downregulated in Panc-1 xenografts with the co-administration. Together, we demonstrate that C6 ceramide sensitizes AT406-mediated anti-pancreatic cancer cell activity possibly via downregulating Bcl-2. - Highlights: • C6 ceramide dramatically potentiates AT406-induced pancreatic cancer cell death. • C6 ceramide facilitates AT406-induced pancreatic cancer cell apoptosis. • C6 ceramide downregulates Bcl-2 to increase AT406's sensitivity in pancreatic cancer cells. • Liposomal C6 ceramide enhances AT406-induced anti-pancreatic cancer activity in vivo.

  1. Inactivated Sendai virus particle upregulates cancer cell expression of intercellular adhesion molecule-1 and enhances natural killer cell sensitivity on cancer cells.

    Science.gov (United States)

    Li, Simin; Nishikawa, Tomoyuki; Kaneda, Yasufumi

    2017-12-01

    We have already reported that the inactivated Sendai virus (hemagglutinating virus of Japan; HVJ) envelope (HVJ-E) has multiple anticancer effects, including induction of cancer-selective cell death and activation of anticancer immunity. The HVJ-E stimulates dendritic cells to produce cytokines and chemokines such as β-interferon, interleukin-6, chemokine (C-C motif) ligand 5, and chemokine (C-X-C motif) ligand 10, which activate both CD8 + T cells and natural killer (NK) cells and recruit them to the tumor microenvironment. However, the effect of HVJ-E on modulating the sensitivity of cancer cells to immune cell attack has yet to be investigated. In this study, we found that HVJ-E induced the production of intercellular adhesion molecule-1 (ICAM-1, CD54), a ligand of lymphocyte function-associated antigen 1, in several cancer cell lines through the activation of nuclear factor-κB downstream of retinoic acid-inducible gene I and the mitochondrial antiviral signaling pathway. The upregulation of ICAM-1 on the surface of cancer cells increased the sensitivity of cancer cells to NK cells. Knocking out expression of ICAM-1 in MDA-MB-231 cells using the CRISPR/Cas9 method significantly reduced the killing effect of NK cells on ICAM-1-depleted MDA-MB-231 cells. In addition, HVJ-E suppressed tumor growth in MDA-MB-231 tumor-bearing SCID mice, and the HVJ-E antitumor effect was impaired when NK cells were depleted by treatment with the anti-asialo GM1 antibody. Our findings suggest that HVJ-E enhances NK cell sensitivity against cancer cells by increasing ICAM-1 expression on the cancer cell surface. © 2017 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.

  2. IDH1-mutant cancer cells are sensitive to cisplatin and an IDH1-mutant inhibitor counteracts this sensitivity.

    Science.gov (United States)

    Khurshed, Mohammed; Aarnoudse, Niels; Hulsbos, Renske; Hira, Vashendriya V V; van Laarhoven, Hanneke W M; Wilmink, Johanna W; Molenaar, Remco J; van Noorden, Cornelis J F

    2018-06-07

    Isocitrate dehydrogenase ( IDH1)-1 is mutated in various types of human cancer, and the presence of this mutation is associated with improved responses to irradiation and chemotherapy in solid tumor cells. Mutated IDH1 (IDH1 MUT ) enzymes consume NADPH to produce d-2-hydroxyglutarate (d-2HG) resulting in the decreased reducing power needed for detoxification of reactive oxygen species (ROS), for example. The objective of the current study was to investigate the mechanism behind the chemosensitivity of the widely-used anticancer agent cisplatin in IDH1 MUT cancer cells. Oxidative stress, DNA damage, and mitochondrial dysfunction caused by cisplatin treatment were monitored in IDH1 MUT HCT116 colorectal cancer cells and U251 glioma cells. We found that exposure to cisplatin induced higher levels of ROS, DNA double-strand breaks (DSBs), and cell death in IDH1 MUT cancer cells, as compared with IDH1 wild-type ( IDH1 WT ) cells. Mechanistic investigations revealed that cisplatin treatment dose dependently reduced oxidative respiration in IDH1 MUT cells, which was accompanied by disturbed mitochondrial proteostasis, indicative of impaired mitochondrial activity. These effects were abolished by the IDH1 MUT inhibitor AGI-5198 and were restored by treatment with d-2HG. Thus, our study shows that altered oxidative stress responses and a vulnerable oxidative metabolism underlie the sensitivity of IDH1 MUT cancer cells to cisplatin.-Khurshed, M., Aarnoudse, N., Hulsbos, R., Hira, V. V. V., van Laarhoven, H. W. M., Wilmink, J. W., Molenaar, R. J., van Noorden, C. J. F. IDH1-mutated cancer cells are sensitive to cisplatin and an IDH1-mutant inhibitor counteracts this sensitivity.

  3. Cellular Morphology-Mediated Proliferation and Drug Sensitivity of Breast Cancer Cells

    Directory of Open Access Journals (Sweden)

    Ryota Domura

    2017-06-01

    Full Text Available The interpretation of the local microenvironment of the extracellular matrix for malignant tumor cells is in intimate relation with metastatic spread of cancer cells involving the associated issues of cellular proliferation and drug responsiveness. This study was aimed to assess the combination of both surface topographies (fiber alignments and different stiffness of the polymeric substrates (poly(l-lactic acid and poly(ε-caprolactone, PLLA and PCL, respectively as well as collagen substrates (coat and gel to elucidate the effect of the cellular morphology on cellular proliferation and drug sensitivities of two different types of breast cancer cells (MDA-MB-231 and MCF-7. The morphological spreading parameter (nucleus/cytoplasm area ratio induced by the anthropogenic substrates has correlated intimately with the cellular proliferation and the drug sensitivity the half maximal inhibitory concentration (IC50 of cancer cells. This study demonstrated the promising results of the parameter for the evaluation of cancer cell malignancy.

  4. Cellular Morphology-Mediated Proliferation and Drug Sensitivity of Breast Cancer Cells.

    Science.gov (United States)

    Domura, Ryota; Sasaki, Rie; Ishikawa, Yuma; Okamoto, Masami

    2017-06-06

    The interpretation of the local microenvironment of the extracellular matrix for malignant tumor cells is in intimate relation with metastatic spread of cancer cells involving the associated issues of cellular proliferation and drug responsiveness. This study was aimed to assess the combination of both surface topographies (fiber alignments) and different stiffness of the polymeric substrates (poly(l-lactic acid) and poly(ε-caprolactone), PLLA and PCL, respectively) as well as collagen substrates (coat and gel) to elucidate the effect of the cellular morphology on cellular proliferation and drug sensitivities of two different types of breast cancer cells (MDA-MB-231 and MCF-7). The morphological spreading parameter (nucleus/cytoplasm area ratio) induced by the anthropogenic substrates has correlated intimately with the cellular proliferation and the drug sensitivity the half maximal inhibitory concentration (IC 50 ) of cancer cells. This study demonstrated the promising results of the parameter for the evaluation of cancer cell malignancy.

  5. 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

  6. 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.

  7. MicroRNA-451 sensitizes lung cancer cells to cisplatin through regulation of Mcl-1.

    Science.gov (United States)

    Cheng, Dezhi; Xu, Yi; Sun, Changzheng; He, Zhifeng

    2016-12-01

    As one of the most widely used chemotherapy drugs for lung cancer, chemoresistance of cisplatin (DPP) is one of the major hindrances in treatment of this malignancy. The microRNAs (miRNAs) have been identified to mediate chemotherapy drug resistance. MiR-451 as a tumor suppressor has been evaluated its potential effect on the sensitivity of cancer cells to DDP. However, the role of miR-451 in regulatory mechanism of chemosensitivity in lung cancer cells is still largely unknown. In this study, we first constructed a cisplatin-resistant A549 cell line (A549/DPP) accompanied with a decreased expression of miR-451 and an increased expression of Mcl-1in the drug resistant cells compared with the parental cells. Exogenous expression of miR-451 level in A549/DPP was found to sensitize their reaction to the treatment of cisplatin, which coincides with reduced expression of Mcl-1. Interestingly, Mcl-1 knockdown in A549/DPP cells increased the chemosensitivity to DPP, suggesting the dependence of Mcl-1 regulation in miR-451 activity. Moreover, miR-451 can restore cisplatin treatment response in cisplatin-resistant xenografts in vivo, while Mcl-1 protein levels were decreased. Thus, these findings provided that in lung cancer cells, tumor suppressor miR-451 enhanced DPP sensitivity via regulation of Mcl-1 expression, which could be served as a novel therapeutic target for the treatment of chemotherapy resistant in lung cancer.

  8. 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 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.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.Taken together, our results propose novel combinatorial approaches to inhibit prostate cancer cell growth. Disulfiram

  9. 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.

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

    International Nuclear Information System (INIS)

    Androic, Ilija; Krämer, Andrea; Yan, Ruilan; Rödel, Franz; Gätje, Regine; Kaufmann, Manfred; Strebhardt, Klaus; Yuan, Juping

    2008-01-01

    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. 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. 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. 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

  11. Irigenin sensitizes TRAIL-induced apoptosis via enhancing pro-apoptotic molecules in gastric cancer cells.

    Science.gov (United States)

    Xu, Ying; Gao, Cheng-Cheng; Pan, Zhen-Guo; Zhou, Chuan-Wen

    2018-02-12

    Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) holds promising value for cancer therapy due to its capacity to induce apoptosis in cancer cells. Nevertheless, TRAIL therapy is greatly hampered by its resistance. Irigenin (Iri), isoflavonoids, can be isolated from the rhizome of Belamcanda chinensis, and has been shown anti-cancer properties. In this study, we explored if Iri could enhance TRAIL-regulated apoptosis in TRAIL resistant gastric cancer cells. Iri significantly potentiated TRAIL-triggered cytotoxicity. Iri alone and TRAIL alone showed no effective role in apoptosis induction, whereas combined treatment with Iri and TRAIL markedly induced apoptosis in cancer cells, as evidenced by the up-regulation of cleaved Caspase-8/-9/-3 and PARP. Additionally, the sensitization to TRAIL was along with the enhancement of pro-apoptotic proteins, including FAS-associated protein with death domain (FADD), death receptor 5 (DR5) and Bax. And suppressing FADD, DR5 and Bax by si RNA significantly reduced the apoptosis and enhanced the cell viability induced by the co-application of Iri and TRAIL. Moreover, the sensitization to TRAIL was accompanied by the decrease of Cellular-FLICE inhibitory protein (c-FLIP), Bcl-2 and Survivin. Additionally, Iri could sensitize TRAIL to produce reactive oxygen species (ROS). Pre-treatment of N-acetyl-cysteine (NAC), ROS scavenger, attenuated Iri plus TRAIL-induced apoptosis and improved cell viability. Finally, combination of Iri and TRAIL inhibited tumor growth in the xenograft model. Collectively, our present study gave new insights into the effects of Iri on potentiating TRAIL-sensitivity, and suggested that Iri could be a potential candidate for sensitizer of TRAIL-resistant cancer cell treatment. Copyright © 2018. Published by Elsevier Inc.

  12. 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.

  13. Enhancement of Bleomycin Sensitivity in Human Lung Cancer Cell ...

    African Journals Online (AJOL)

    Methods: The inhibitory effect of bleomycin on A549 cells was determined by incubating the cells for 24 h in different .... also include advantageous psychological effects such as .... cyclooxygenase-2 enzyme inhibitors: A rational advance?

  14. Constitutively activated ERK sensitizes cancer cells to doxorubicin ...

    Indian Academy of Sciences (India)

    2017-02-03

    Feb 3, 2017 ... Involvement of p53-EGFR-ERK pathway. RATNA KUMARI. 1,† ... malignancies and is reported to be involved in the develop- ment of resistance to ... Culture Collection (ATCC, VA, USA) and maintained in our inhouse National ..... turns, universal health coverage, and cancer mortality in high- income and ...

  15. Expression of Ku correlates with radiation sensitivities in the head and neck cancer cell lines

    International Nuclear Information System (INIS)

    Lee, Sang Wook; Yu, Eun Sil; Yi, So Lyoung; Son, Se Hee; Kim, Jong Hoon; Ahn, Seung Do; Shin, Seong Soo; Choi, Eun Kyung

    2004-01-01

    DNA-dependent protein kinase (DNA-PK) is a serine/threonine kinase consisting of a 470 kDa catalytic subunit (DNA-PKcs) and a heterodimeric regulatory complex, called Ku, which is composed of 70 kDa (Ku 70) and 86 kDa (Ku 80) proteins. The DNA-PK has been shown to play a pivotal role in rejoining DNA double-strand-breaks (dsb) in mammalian cells. The purpose of this study is to examine the relationship between the level of Ku expression and radiation sensitivity. Nine head and neck, cancer cell lines showed various intrinsic radiation sensitivities. Among the nine, AMC-HN-3 cell was the most sensitive for X-ray irradiation and AMC-HN-9 cell was the most resistance. The most sensitive and resistant cell lines were selected and the test sensitivity of radiation and expression of Ku were measured. Radiation sensitivity was obtained by colony forming assay and Ku protein expression using Western blot analysis. Ku80 increased expression by radiation, wheras Ku70 did not. Overexpression of Ku80 protein increased radiation resistance in AMC-HN9 cell line. There was a correlation between Ku80 expression and radiation resistance. Ku80 was shown to play an important role in radiation damage response. Induction of Ku80 expression had an important role in DNA damage repair by radiation. Ku80 expression may be an effective predictive assay of radiosensitivity on head and neck cancer

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

    International Nuclear Information System (INIS)

    Oommen, Deepu; Yiannakis, Dennis; Jha, Awadhesh N.

    2016-01-01

    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.

  17. 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.

  18. Tetrathiomolybdate sensitizes ovarian cancer cells to anticancer drugs doxorubicin, fenretinide, 5-fluorouracil and mitomycin C

    International Nuclear Information System (INIS)

    Kim, Kyu Kwang; Lange, Thilo S; Singh, Rakesh K; Brard, Laurent; Moore, Richard G

    2012-01-01

    Our recent study showed that tetrathiomolybdate (TM), a drug to treat copper overload disorders, can sensitize drug-resistant endometrial cancer cells to reactive oxygen species (ROS)-generating anticancer drug doxorubicin. To expand these findings in the present study we explore TM efficacy in combination with a spectrum of ROS-generating anticancer drugs including mitomycin C, fenretinide, 5-fluorouracil and doxorubicin in ovarian cancer cells as a model system. The effects of TM alone or in combination with doxorubicin, mitomycin C, fenretinide, or 5-fluorouracil were evaluated using a sulforhodamine B assay. Flow cytometry was used to detect the induction of apoptosis and ROS generation. Immunoblot analysis was carried out to investigate changes in signaling pathways. TM potentiated doxorubicin-induced cytotoxicity and modulated key regulators of apoptosis (PARP, caspases, JNK and p38 MAPK) in SKOV-3 and A2780 ovarian cancer cell lines. These effects were linked to the increased production of ROS, as shown in SKOV-3 cells. ROS scavenging by ascorbic acid blocked the sensitization of cells by TM. TM also sensitized SKOV-3 to mitomycin C, fenretinide, and 5-fluorouracil. The increased cytotoxicity of these drugs in combination with TM was correlated with the activity of ROS, loss of a pro-survival factor (e.g. XIAP) and the appearance of a pro-apoptotic marker (e.g. PARP cleavage). Our data show that TM increases the efficacy of various anticancer drugs in ovarian cancer cells in a ROS-dependent manner

  19. The Cancer Cell Line Encyclopedia enables predictive modeling 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.

    2012-01-01

    The systematic translation of cancer genomic data into knowledge of tumor biology and therapeutic avenues 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 pharmacologic annotation is available1. 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 pharmacologic profiles for 24 anticancer drugs across 479 of the 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. Altogether, our results suggest 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 regimens2. PMID:22460905

  20. Protein kinase C β inhibits autophagy and sensitizes cervical cancer Hela cells to cisplatin.

    Science.gov (United States)

    Li, Na; Zhang, Wei

    2017-04-28

    Recently, autophagy has been indicated to play an essential role in various biological events, such as the response of cervical cancer cells to chemotherapy. However, the exact signalling mechanism that regulates autophagy during chemotherapy remains unclear. In the present study, we investigated the regulation by cisplatin on protein kinase C β (PKC β), on B-cell lymphoma 2 (Bcl-2) and on apoptosis in cervical cancer Hela cells. And then we examined the regulation by cisplatin on autophagy and the role of autophagy on the chemotherapy in Hela cells. In addition, the regulation of the PKC β on the autophagy was also investigated. Our results indicated that cisplatin promoted PKC β in Hela cells. The PKC β inhibitor reduced the cisplatin-induced apoptosis, whereas increased the cisplatin-induced autophagy in Hela cells. On the other side, the PKC β overexpression aggravated the cisplatin-induced apoptosis, whereas down-regulated the cisplatin-induced autophagy. Taken together, our study firstly recognized the involvement of PKC β in the cytotoxicity of cisplatin via inhibiting autophagy in cervical cancer cells. We propose that PKC β would sensitize cervical cancer cells to chemotherapy via reducing the chemotherapy induced autophagy in cancer cells. © 2017 The Author(s).

  1. Identification of breast cancer cell subtypes sensitive to ATG4B inhibition.

    Science.gov (United States)

    Bortnik, Svetlana; Choutka, Courtney; Horlings, Hugo M; Leung, Samuel; Baker, Jennifer H; Lebovitz, Chandra; Dragowska, Wieslawa H; Go, Nancy E; Bally, Marcel B; Minchinton, Andrew I; Gelmon, Karen A; Gorski, Sharon M

    2016-10-11

    Autophagy, a lysosome-mediated degradation and recycling process, functions in advanced malignancies to promote cancer cell survival and contribute to cancer progression and drug resistance. While various autophagy inhibition strategies are under investigation for cancer treatment, corresponding patient selection criteria for these autophagy inhibitors need to be developed. Due to its central roles in the autophagy process, the cysteine protease ATG4B is one of the autophagy proteins being pursued as a potential therapeutic target. In this study, we investigated the expression of ATG4B in breast cancer, a heterogeneous disease comprised of several molecular subtypes. We examined a panel of breast cancer cell lines, xenograft tumors, and breast cancer patient specimens for the protein expression of ATG4B, and found a positive association between HER2 and ATG4B protein expression. We showed that HER2-positive cells, but not HER2-negative breast cancer cells, require ATG4B to survive under stress. In HER2-positive cells, cytoprotective autophagy was dependent on ATG4B under both starvation and HER2 inhibition conditions. Combined knockdown of ATG4B and HER2 by siRNA resulted in a significant decrease in cell viability, and the combination of ATG4B knockdown with trastuzumab resulted in a greater reduction in cell viability compared to trastuzumab treatment alone, in both trastuzumab-sensitive and -resistant HER2 overexpressing breast cancer cells. Together these results demonstrate a novel association of ATG4B positive expression with HER2 positive breast cancers and indicate that this subtype is suitable for emerging ATG4B inhibition strategies.

  2. PCA3 Silencing Sensitizes Prostate Cancer Cells to Enzalutamide-mediated Androgen Receptor Blockade.

    Science.gov (United States)

    Özgür, Emre; Celik, Ayca Iribas; Darendeliler, Emin; Gezer, Ugur

    2017-07-01

    Prostate cancer (PCa) is an androgen-dependent disease. Novel anti-androgens (i.e. enzalutamide) have recently been developed for the treatment of patients with metastatic castration-resistant prostate cancer (CRPC). Evidence is accumulating that prostate cancer antigen 3 (PCA3) is involved in androgen receptor (AR) signaling. Here, in combination with enzalutamide-mediated AR blockade, we investigated the effect of PCA3 targeting on the viability of PCa cells. In hormone-sensitive LNCaP cells, AR-overexpressing LNCaP-AR + cells and VCaP cells (representing CRPC), PCA3 was silenced using siRNA oligonucleotides. Gene expression and cell viability was assessed in PCA3-silenced and/or AR-blocked cells. PCA3 targeting reduced the expression of AR-related genes (i.e. prostate-specific antigen (PSA) and prostate-specific transcript 1 (non-protein coding) (PCGEM1)) and potentiated the effect of enzalutamide. Proliferation of PCa cells was suppressed upon PCA3 silencing with a greater effect in LNCaP-AR + cells. Furthermore, PCA3 silencing sensitized PCa cells to enzalutamide-induced loss of cell growth. PCA3, as a therapeutic target in PCa, might be used to potentiate AR antagonists. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

  3. Sensitization of gastric cancer cells to alkylating agents by glaucocalyxin B via cell cycle arrest and enhanced cell death.

    Science.gov (United States)

    Ur Rahman, Muhammad Saif; Zhang, Ling; Wu, Lingyan; Xie, Yuqiong; Li, Chunchun; Cao, Jiang

    2017-01-01

    Severe side effects are major problems with chemotherapy of gastric cancer (GC). These side effects can be reduced by using sensitizing agents in combination with therapeutic drugs. In this study, the low/nontoxic dosage of glaucocalyxin B (GLB) was used with other DNA linker agents mitomycin C (MMC), cisplatin (DDP), or cyclophosphamide (CTX) to treat GC cells. Combined effectiveness of GLB with drugs was determined by proliferation assay. The molecular mechanisms associated with cell proliferation, migration, invasion, cell cycle, DNA repair/replication, apoptosis, and autophagy were investigated by immunoblotting for key proteins involved. Cell cycle and apoptosis analysis were performed by flow cytometry. Reactive oxygen species level was also examined for identification of its role in apoptosis. Proliferation assay revealed that the addition of 5 µM GLB significantly sensitizes gastric cancer SGC-7901 cells to MMC, DDP, and CTX by decreasing half-maximal inhibitory concentration (IC 50 ) by up to 75.40%±5%, 45.10%±5%, and 52.10%±5%, respectively. GLB + drugs decreased the expression level of proteins involved in proliferation and migration, suggesting the anticancer potential of GLB + drugs. GLB + MMC, GLB + CTX, and GLB + DDP arrest the cells in G 0 /G 1 and G 1 /S phase, respectively, which may be the consequence of significant decrease in the level of enzymes responsible for DNA replication and telomerase shortening. Combined use of GLB with these drugs also induces DNA damage and apoptosis by activating caspase/PARP pathways and increased production of reactive oxygen species and increased autophagy in GC cells. GLB dosage sensitizes GC cells to the alkylating agents via arresting the cell cycle and enhancing cell death. This is of significant therapeutic importance in the reduction of side effects associated with these drugs.

  4. Membrane microparticles mediate transfer of P-glycoprotein to drug sensitive cancer cells.

    Science.gov (United States)

    Bebawy, M; Combes, V; Lee, E; Jaiswal, R; Gong, J; Bonhoure, A; Grau, G E R

    2009-09-01

    Multidrug resistance (MDR), a significant impediment to the successful treatment of cancer clinically, has been attributed to the overexpression of P-glycoprotein (P-gp), a plasma membrane multidrug efflux transporter. P-gp maintains sublethal intracellular drug concentrations by virtue of its drug efflux capacity. The cellular regulation of P-gp expression is currently known to occur at either pre- or post-transcriptional levels. In this study, we identify a 'non-genetic' mechanism whereby microparticles (MPs) serve as vectors in the acquisition and spread of MDR. MPs isolated from drug-resistant cancer cells (VLB(100)) were co-cultured with drug sensitive cells (CCRF-CEM) over a 4 h period to allow for MP binding and P-gp transfer. Presence of P-gp on MPs was established using flow cytometry (FCM) and western blotting. Whole-cell drug accumulation assays using rhodamine 123 and daunorubicin (DNR) were carried out to validate the transfer of functional P-gp after co-culture. We establish that MPs shed in vitro from drug-resistant cancer cells incorporate cell surface P-gp from their donor cells, effectively bind to drug-sensitive recipient cells and transfer functional P-gp to the latter. These findings serve to substantially advance our understanding of the molecular basis for the emergence of MDR in cancer clinically and lead to new treatment strategies which target and inhibit MP mediated transfer of P-gp during the course of treatment.

  5. Parainfluenza Virus Infection Sensitizes Cancer Cells to DNA-Damaging Agents: Implications for Oncolytic Virus Therapy.

    Science.gov (United States)

    Fox, Candace R; Parks, Griffith D

    2018-04-01

    A parainfluenza virus 5 (PIV5) with mutations in the P/V gene (P/V-CPI - ) is restricted for spread in normal cells but not in cancer cells in vitro and is effective at reducing tumor burdens in mouse model systems. Here we show that P/V-CPI - infection of HEp-2 human laryngeal cancer cells results in the majority of the cells dying, but unexpectedly, over time, there is an emergence of a population of cells that survive as P/V-CPI - persistently infected (PI) cells. P/V-CPI - PI cells had elevated levels of basal caspase activation, and viability was highly dependent on the activity of cellular inhibitor-of-apoptosis proteins (IAPs) such as Survivin and XIAP. In challenge experiments with external inducers of apoptosis, PI cells were more sensitive to cisplatin-induced DNA damage and cell death. This increased cisplatin sensitivity correlated with defects in DNA damage signaling pathways such as phosphorylation of Chk1 and translocation of damage-specific DNA binding protein 1 (DDB1) to the nucleus. Cisplatin-induced killing of PI cells was sensitive to the inhibition of wild-type (WT) p53-inducible protein 1 (WIP1), a phosphatase which acts to terminate DNA damage signaling pathways. A similar sensitivity to cisplatin was seen with cells during acute infection with P/V-CPI - as well as during acute infections with WT PIV5 and the related virus human parainfluenza virus type 2 (hPIV2). Our results have general implications for the design of safer paramyxovirus-based vectors that cannot establish PI as well as the potential for combining chemotherapy with oncolytic RNA virus vectors. IMPORTANCE There is intense interest in developing oncolytic viral vectors with increased potency against cancer cells, particularly those cancer cells that have gained resistance to chemotherapies. We have found that infection with cytoplasmically replicating parainfluenza virus can result in increases in the killing of cancer cells by agents that induce DNA damage, and this is linked

  6. 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.

  7. 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

  8. Plectin deficiency in liver cancer cells promotes cell migration and sensitivity to sorafenib treatment.

    Science.gov (United States)

    Cheng, Chiung-Chi; Chao, Wei-Ting; Liao, Chen-Chun; Tseng, Yu-Hui; Lai, Yen-Chang Clark; Lai, Yih-Shyong; Hsu, Yung-Hsiang; Liu, Yi-Hsiang

    2018-01-02

    Plectin involved in activation of kinases in cell signaling pathway and plays important role in cell morphology and migration. Plectin knockdown promotes cell migration by activating focal adhesion kinase and Rac1-GTPase activity in liver cells. Sorafenib is a multi-targeting tyrosine kinase inhibitor that improves patient survival on hepatocellular carcinoma. The aim of this study is to investigate the correlation between the expression of plectin and cell migration as well as the sensitivity of hepatoma cell lines exposing to sorafenib. Hepatoma cell lines PLC/PRF/5 and HepG2 were used to examine the level of plectin expression and cell migration in comparison with Chang liver cell line. In addition, sensitivity of the 3 cell lines to sorafenib treatment was also measured. Expression of plectin was lower in PLC/PRF/5 and HepG2 hepatoma cells than that of Chang liver cells whereas HepG2 and PLC/PRF/5 cells exhibit higher rate of cell migration in trans-well migration assay. Immunohistofluorecent staining on E-cadherin revealed the highest rate of collective cell migration in HepG2 cells and the lowest was found in Chang liver cells. Likewise, HepG2 cell line was most sensitive to sorafenib treatment and Chang liver cells exhibited the least sensitivity. The drug sensitivity to sorafenib treatment showed inverse correlation with the expression of plectin. We suggest that plectin deficiency and increased E-cadherin in hepatoma cells were associated with higher rates of cell motility, collective cell migration as well as higher drug sensitivity to sorafenib treatment.

  9. Downregulation of hPMC2 imparts chemotherapeutic sensitivity to alkylating agents in breast cancer cells.

    Science.gov (United States)

    Krishnamurthy, Nirmala; Liu, Lili; Xiong, Xiahui; Zhang, Junran; Montano, Monica M

    2015-01-01

    Triple negative breast cancer cell lines have been reported to be resistant to the cyotoxic effects of temozolomide (TMZ). We have shown previously that a novel protein, human homolog of Xenopus gene which Prevents Mitotic Catastrophe (hPMC2) has a role in the repair of estrogen-induced abasic sites. Our present study provides evidence that downregulation of hPMC2 in MDA-MB-231 and MDA-MB-468 breast cancer cells treated with temozolomide (TMZ) decreases cell survival. This increased sensitivity to TMZ is associated with an increase in number of apurinic/apyrimidinic (AP) sites in the DNA. We also show that treatment with another alkylating agent, BCNU, results in an increase in AP sites and decrease in cell survival. Quantification of western blot analyses and immunofluorescence experiments reveal that treatment of hPMC2 downregulated cells with TMZ results in an increase in γ-H2AX levels, suggesting an increase in double strand DNA breaks. The enhancement of DNA double strand breaks in TMZ treated cells upon downregulation of hPCM2 is also revealed by the comet assay. Overall, we provide evidence that downregulation of hPMC2 in breast cancer cells increases cytotoxicity of alkylating agents, representing a novel mechanism of treatment for breast cancer. Our data thus has important clinical implications in the management of breast cancer and brings forth potentially new therapeutic strategies.

  10. Silencing of the Wnt transcription factor TCF4 sensitizes colorectal cancer cells to (chemo-) radiotherapy

    Science.gov (United States)

    Kendziorra, Emil; Ahlborn, Kerstin; Spitzner, Melanie; Rave-Fränk, Margret; Emons, Georg; Gaedcke, Jochen; Kramer, Frank; Wolff, Hendrik A.; Becker, Heinz; Beissbarth, Tim; Ebner, Reinhard; Ghadimi, B.Michael; Pukrop, Tobias; Ried, Thomas; Grade, Marian

    2011-01-01

    A considerable percentage of rectal cancers are resistant to standard preoperative chemoradiotherapy. Because patients with a priori-resistant tumors do not benefit from multimodal treatment, understanding and overcoming this resistance remains of utmost clinical importance. We recently reported overexpression of the Wnt transcription factor TCF4, also known as TCF7L2, in rectal cancers that were resistant to 5-fluorouracil-based chemoradiotherapy. Because Wnt signaling has not been associated with treatment response, we aimed to investigate whether TCF4 mediates chemoradioresistance. RNA interference-mediated silencing of TCF4 was employed in three colorectal cancer (CRC) cell lines, and sensitivity to (chemo-) radiotherapy was assessed using a standard colony formation assay. Silencing of TCF4 caused a significant sensitization of CRC cells to clinically relevant doses of X-rays. This effect was restricted to tumor cells with high T cell factor (TCF) reporter activity, presumably in a β-catenin-independent manner. Radiosensitization was the consequence of (i) a transcriptional deregulation of Wnt/TCF4 target genes, (ii) a silencing-induced G2/M phase arrest, (iii) an impaired ability to adequately halt cell cycle progression after radiation and (iv) a compromised DNA double strand break repair as assessed by γH2AX staining. Taken together, our results indicate a novel mechanism through which the Wnt transcription factor TCF4 mediates chemoradioresistance. Moreover, they suggest that TCF4 is a promising molecular target to sensitize resistant tumor cells to (chemo-) radiotherapy. PMID:21983179

  11. 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.

  12. Caveolin-1 sensitizes cisplatin-induced lung cancer cell apoptosis via superoxide anion-dependent mechanism.

    Science.gov (United States)

    Pongjit, Kanittha; Chanvorachote, Pithi

    2011-12-01

    Caveolin-1 (Cav-1) expression frequently found in lung cancer was linked with disease prognosis and progression. This study reveals for the first time that Cav-1 sensitizes cisplatin-induced lung carcinoma cell death by the mechanism involving oxidative stress modulation. We established stable Cav-1 overexpressed (H460/Cav-1) cells and investigated their cisplatin susceptibility in comparison with control-transfected cells and found that Cav-1 expression significantly enhanced cisplatin-mediated cell death. Results indicated that the different response to cisplatin between these cells was resulted from different level of superoxide anion induced by cisplatin. Inhibitory study revealed that superoxide anion inhibitor MnTBAP could inhibit cisplatin-mediated toxicity only in H460/Cav-1 cells while had no effect on H460 cells. Further, superoxide anion detected by DHE probe indicated that H460/Cav-1 cells generated significantly higher superoxide anion level in response to cisplatin than that of control cells. The role of Cav-1 in regulating cisplatin sensitivity was confirmed in shRNA-mediated Cav-1 down-regulated (H460/shCav-1) cells and the cells exhibited decreased cisplatin susceptibility and superoxide generation. In summary, these findings reveal novel aspects regarding role of Cav-1 in modulating oxidative stress induced by cisplatin, possibly providing new insights for cancer biology and cisplatin-based chemotherapy.

  13. 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.

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

    International Nuclear Information System (INIS)

    Kim, Ju-Hwa; Yoo, Hye-In; Kang, Han Sung; Ro, Jungsil; Yoon, Sungpil

    2012-01-01

    Highlights: ► Sal sensitizes antimitotic drugs-treated cancer cells. ► Sal sensitizes them by prevention of G2 arrest and reduced cyclin D1 levels. ► Sal also sensitizes them by increasing DNA damage and reducing p21 level. ► 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.

  15. [Monocarboxylate transporter 1 enhances the sensitivity of breast cancer cells to 3-bromopyruvate in vitro].

    Science.gov (United States)

    Li, Qi-Xiang; Zhang, Pei; Liu, Fang; Wang, Xian-Zhi; Li, Lu; Wang, Zhong-Kun; Jiang, Chen-Chen; Zheng, Hai-Lun; Liu, Hao

    2017-05-20

    To investigate the role of monocarboxylate transporter 1 (MCT1) in enhancing the sensitivity of breast cancer cells to 3-bromopyruvate (3-BrPA). The inhibitory effect of 3-BrPA on the proliferation of breast cancer cells was assessed with MTT assay, and brominated propidium bromide single staining flow cytometry was used for detecting the cell apoptosis. An ELISA kit was used to detect the intracellular levels of hexokinase II, lactate dehydrogenase, lactate, and adenosine triphosphate, and Western blotting was performed to detect the expression of MCT1. MDA-MB-231 cells were transiently transfected with MCT1 cDNA for over-expressing MCT1, and the effect of 3-BrPA on the cell proliferation and adenosine triphosphate level was deteced. 3-BrPA did not produce significant effects on the proliferation and apoptosis of MDA-MB-231 cells, and the cells treated with 200 µmol/L 3-BrPA for 24 h showed an inhibition rate and an apoptosis rate of only 8.72% and 7.8%, respectively. The same treatment, however, produced an inhibition rate and an apoptosis rate of 84.6% and 82.3% in MCF-7 cells, respectively. In MDA-MB-231 cells with MCT1 overexpression, 200 µmol/L 3-BrPA resulted in an inhibition rate of 72.44%, significantly higher than that in the control cells (P<0.05); treatment of the cells with 25, 50, 100, and 200 µmol/L 3-BrPA for 6 h resulted in intracellular adenosine triphosphate levels of 96.98%, 88.44%, 43.3% and 27.56% relative to the control level respectively. MCT1 can enhance the sensitivity of breast cancer cells to 3-BrPA possibly by transporting 3-BrPA into cells to inhibit cell glycolysis.

  16. 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. © 2016 Wiley Periodicals, Inc.

  17. Cell death induced by taxanes in sensitive and resistant breast cancer cells

    Czech Academy of Sciences Publication Activity Database

    Ehrlichová, Marie; Truksa, Jaroslav; Naďová, Zuzana; Gut, I.; Kovář, Jan

    2004-01-01

    Roč. 37, č. 2 (2004), s. 120-121 ISSN 0960-7722. [Meeting of the European study group for cell proliferation /26./. Praha, 13.05.2004-16.05.2004] R&D Projects: GA MZd NL6715 Keywords : breast cancer cells * cell death * taxanes Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.907, year: 2004

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

    Science.gov (United States)

    Doherty, Ben; Lawlor, Denise; Gillet, Jean-Pierre; Gottesman, Michael; O'Leary, John J; Stordal, Britta

    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. A Taqman low-density array was used to characterize the expression of 380 genes previously associated with chemoresistance. Identified pathways were further analyzed using cytotoxicity assays, metabolomics and western blots. KB-8-5-11 cells were sensitive to CuSO4 and the glutathione inhibitor buthionine sulphoximine. Expression of ATPase, Cu(2+) transporting alpha (ATP7A) and ATP7B were decreased at the protein and gene levels respectively in KB-8-5-11. KB-8-5-11 had decreased gene expression of glutathione S-transferase pi 1 (GSTP1), GSTA4 and GSTK1. Cisplatin treatment significantly lowered total cellular glutathione in parental KB-3-1 cells. Glutathione also tended to be lower in KB-8-5-11 cells compared to KB-3-1 cells. KB-8-5-11 cells have alterations in their copper transporters and glutathione metabolism, contributing to their cisplatin-sensitive phenotype.

  19. 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.

  20. Suppression of progranulin expression inhibits bladder cancer growth and sensitizes cancer cells to cisplatin.

    Science.gov (United States)

    Buraschi, Simone; Xu, Shi-Qiong; Stefanello, Manuela; Moskalev, Igor; Morcavallo, Alaide; Genua, Marco; Tanimoto, Ryuta; Birbe, Ruth; Peiper, Stephen C; Gomella, Leonard G; Belfiore, Antonino; Black, Peter C; Iozzo, Renato V; Morrione, Andrea

    2016-06-28

    We have recently demonstrated a critical role for progranulin in bladder cancer. Progranulin contributes, as an autocrine growth factor, to the transformed phenotype by modulating Akt-and MAPK-driven motility, invasion and anchorage-independent growth. Progranulin also induces F-actin remodeling by interacting with the F-actin binding protein drebrin. In addition, progranulin is overexpressed in invasive bladder cancer compared to normal tissue controls, suggesting that progranulin might play a key role in driving the transition to the invasive phenotype of urothelial cancer. However, it is not established whether targeting progranulin could have therapeutic effects on bladder cancer. In this study, we stably depleted urothelial cancer cells of endogenous progranulin by shRNA approaches and determined that progranulin depletion severely inhibited the ability of tumorigenic urothelial cancer cells to migrate, invade and grow in anchorage-independency. We further demonstrate that progranulin expression is critical for tumor growth in vivo, in both xenograft and orthotopic tumor models. Notably, progranulin levels correlated with response to cisplatin treatment and were upregulated in bladder tumors. Our data indicate that progranulin may constitute a novel target for therapeutic intervention in bladder tumors. In addition, progranulin may serve as a novel biomarker for bladder cancer.

  1. Sensitization of gastric cancer cells to alkylating agents by glaucocalyxin B via cell cycle arrest and enhanced cell death

    Directory of Open Access Journals (Sweden)

    Ur Rahman MS

    2017-08-01

    Full Text Available Muhammad Saif Ur Rahman,1 Ling Zhang,2 Lingyan Wu,1 Yuqiong Xie,1 Chunchun Li,1 Jiang Cao1 1Clinical Research Center, 2Cardiovascular Key Laboratory of Zhejiang Province, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang Province, People’s Republic of China Abstract: Severe side effects are major problems with chemotherapy of gastric cancer (GC. These side effects can be reduced by using sensitizing agents in combination with therapeutic drugs. In this study, the low/nontoxic dosage of glaucocalyxin B (GLB was used with other DNA linker agents mitomycin C (MMC, cisplatin (DDP, or cyclophosphamide (CTX to treat GC cells. Combined effectiveness of GLB with drugs was determined by proliferation assay. The molecular mechanisms associated with cell proliferation, migration, invasion, cell cycle, DNA repair/replication, apoptosis, and autophagy were investigated by immunoblotting for key proteins involved. Cell cycle and apoptosis analysis were performed by flow cytometry. Reactive oxygen species level was also examined for identification of its role in apoptosis. Proliferation assay revealed that the addition of 5 µM GLB significantly sensitizes gastric cancer SGC-7901 cells to MMC, DDP, and CTX by decreasing half-maximal inhibitory concentration (IC50 by up to 75.40%±5%, 45.10%±5%, and 52.10%±5%, respectively. GLB + drugs decreased the expression level of proteins involved in proliferation and migration, suggesting the anticancer potential of GLB + drugs. GLB + MMC, GLB + CTX, and GLB + DDP arrest the cells in G0/G1 and G1/S phase, respectively, which may be the consequence of significant decrease in the level of enzymes responsible for DNA replication and telomerase shortening. Combined use of GLB with these drugs also induces DNA damage and apoptosis by activating caspase/PARP pathways and increased production of reactive oxygen species and increased autophagy in GC cells. GLB dosage sensitizes GC

  2. In silico modeling predicts drug sensitivity of patient-derived cancer cells.

    Science.gov (United States)

    Pingle, Sandeep C; Sultana, Zeba; Pastorino, Sandra; Jiang, Pengfei; Mukthavaram, Rajesh; Chao, Ying; Bharati, Ila Sri; Nomura, Natsuko; Makale, Milan; Abbasi, Taher; Kapoor, Shweta; Kumar, Ansu; Usmani, Shahabuddin; Agrawal, Ashish; Vali, Shireen; Kesari, Santosh

    2014-05-21

    Glioblastoma (GBM) is an aggressive disease associated with poor survival. It is essential to account for the complexity of GBM biology to improve diagnostic and therapeutic strategies. This complexity is best represented by the increasing amounts of profiling ("omics") data available due to advances in biotechnology. The challenge of integrating these vast genomic and proteomic data can be addressed by a comprehensive systems modeling approach. Here, we present an in silico model, where we simulate GBM tumor cells using genomic profiling data. We use this in silico tumor model to predict responses of cancer cells to targeted drugs. Initially, we probed the results from a recent hypothesis-independent, empirical study by Garnett and co-workers that analyzed the sensitivity of hundreds of profiled cancer cell lines to 130 different anticancer agents. We then used the tumor model to predict sensitivity of patient-derived GBM cell lines to different targeted therapeutic agents. Among the drug-mutation associations reported in the Garnett study, our in silico model accurately predicted ~85% of the associations. While testing the model in a prospective manner using simulations of patient-derived GBM cell lines, we compared our simulation predictions with experimental data using the same cells in vitro. This analysis yielded a ~75% agreement of in silico drug sensitivity with in vitro experimental findings. These results demonstrate a strong predictability of our simulation approach using the in silico tumor model presented here. Our ultimate goal is to use this model to stratify patients for clinical trials. By accurately predicting responses of cancer cells to targeted agents a priori, this in silico tumor model provides an innovative approach to personalizing therapy and promises to improve clinical management of cancer.

  3. Inhibition of the CSF-1 receptor sensitizes ovarian cancer cells to cisplatin.

    Science.gov (United States)

    Yu, Rong; Jin, Hao; Jin, Congcong; Huang, Xuefeng; Lin, Jinju; Teng, Yili

    2018-03-01

    Ovarian cancer is one of the most common female malignancies, and cisplatin-based chemotherapy is routinely used in locally advanced ovarian cancer patients. Acquired or de novo cisplatin resistance remains the barrier to patient survival, and the mechanisms of cisplatin resistance are still not well understood. In the current study, we found that colony-stimulating-factor-1 receptor (CSF-1R) was upregulated in cisplatin-resistant SK-OV-3 and CaoV-3 cells. Colony-stimulating-factor-1 receptor knockdown suppressed proliferation and enhanced apoptosis in cisplatin-resistant SK-OV-3 and CaoV-3 cells. However, CSF-1R overexpression had inverse effects. While parental SK-OV-3 and CaoV-3 cells were more resistant to cisplatin after CSF-1R overexpression, CSF-1R knockdown in SK-OV-3 and CaoV-3 cells promoted cisplatin sensitivity. Overexpression and knockdown studies also showed that CSF-1R significantly promoted active AKT and ERK1/2 signalling pathways in cisplatin-resistant cells. Furthermore, a combination of cisplatin and CSF-1R inhibitor effectively inhibited tumour growth in xenografts. Taken together, our results provide the first evidence that CSF-1R inhibition can sensitize cisplatin-refractory ovarian cancer cells. This study may help to increase understanding of the molecular mechanisms underlying cisplatin resistance in tumours. Copyright © 2018 John Wiley & Sons, Ltd.

  4. Cytokeratin 19 (KRT19) has a Role in the Reprogramming of Cancer Stem Cell-Like Cells to Less Aggressive and More Drug-Sensitive Cells

    Science.gov (United States)

    Kim, Kyeongseok; Yang, Gwang-Mo; Choi, Hye Yeon

    2018-01-01

    Cytokeratin 19 (KRT19) is a cytoplasmic intermediate filament protein, which is responsible for structural rigidity and multipurpose scaffolds. In several cancers, KRT19 is overexpressed and may play a crucial role in tumorigenic transformation. In our previous study, we revealed the role of KRT19 as signaling component which mediated Wnt/NOTCH crosstalk through NUMB transcription in breast cancer. Here, we investigated the function of KRT19 in cancer reprogramming and drug resistance in breast cancer cells. We found that expression of KRT19 was attenuated in several patients-derived breast cancer tissues and patients with a low expression of KRT19 were significantly correlated with poor prognosis in breast cancer patients. Consistently, highly aggressive and drug-resistant breast cancer patient-derived cancer stem cell-like cells (konkuk university-cancer stem cell-like cell (KU-CSLCs)) displayed higher expression of cancer stem cell (CSC) markers, including ALDH1, CXCR4, and CD133, but a much lower expression of KRT19 than that is seen in highly aggressive triple negative breast cancer MDA-MB231 cells. Moreover, we revealed that the knockdown of KRT19 in MDA-MB231 cells led to an enhancement of cancer properties, such as cell proliferation, sphere formation, migration, and drug resistance, while the overexpression of KRT19 in KU-CSLCs resulted in the significant attenuation of cancer properties. KRT19 regulated cancer stem cell reprogramming by modulating the expression of cancer stem cell markers (ALDH1, CXCR4, and CD133), as well as the phosphorylation of Src and GSK3β (Tyr216). Therefore, our data may imply that the modulation of KRT19 expression could be involved in cancer stem cell reprogramming and drug sensitivity, which might have clinical implications for cancer or cancer stem cell treatment. PMID:29747452

  5. Cytokeratin 19 (KRT19) has a Role in the Reprogramming of Cancer Stem Cell-Like Cells to Less Aggressive and More Drug-Sensitive Cells.

    Science.gov (United States)

    Saha, Subbroto Kumar; Kim, Kyeongseok; Yang, Gwang-Mo; Choi, Hye Yeon; Cho, Ssang-Goo

    2018-05-09

    Cytokeratin 19 ( KRT19 ) is a cytoplasmic intermediate filament protein, which is responsible for structural rigidity and multipurpose scaffolds. In several cancers, KRT19 is overexpressed and may play a crucial role in tumorigenic transformation. In our previous study, we revealed the role of KRT19 as signaling component which mediated Wnt/NOTCH crosstalk through NUMB transcription in breast cancer. Here, we investigated the function of KRT19 in cancer reprogramming and drug resistance in breast cancer cells. We found that expression of KRT19 was attenuated in several patients-derived breast cancer tissues and patients with a low expression of KRT19 were significantly correlated with poor prognosis in breast cancer patients. Consistently, highly aggressive and drug-resistant breast cancer patient-derived cancer stem cell-like cells (konkuk university-cancer stem cell-like cell (KU-CSLCs)) displayed higher expression of cancer stem cell (CSC) markers, including ALDH1 , CXCR4 , and CD133 , but a much lower expression of KRT19 than that is seen in highly aggressive triple negative breast cancer MDA-MB231 cells. Moreover, we revealed that the knockdown of KRT19 in MDA-MB231 cells led to an enhancement of cancer properties, such as cell proliferation, sphere formation, migration, and drug resistance, while the overexpression of KRT19 in KU-CSLCs resulted in the significant attenuation of cancer properties. KRT19 regulated cancer stem cell reprogramming by modulating the expression of cancer stem cell markers ( ALDH1 , CXCR4 , and CD133 ), as well as the phosphorylation of Src and GSK3β (Tyr216). Therefore, our data may imply that the modulation of KRT19 expression could be involved in cancer stem cell reprogramming and drug sensitivity, which might have clinical implications for cancer or cancer stem cell treatment.

  6. Radiation sensitization by dihydroartemisinin on human HeLa cells of cervical cancer

    International Nuclear Information System (INIS)

    Chen Xialin; Cao Jianping; Ji Rong; Zhu Wei; Liu Yang; Gong Xiaomei; Tang Yan; Pan Chunyan; Fan Saijun

    2009-01-01

    Objective: To investigate the radiosensitizing effects of dihydroartemisinin (DHA) on human HeLa cells of cervical cancer irradiated by X rays. Methods: Cell growth kinetics was determined using MTF assay. Cell survival was analyzed by elonogenic assay. The change of cell cycle and apeptosis was measured by flow cytometry. Results: Dihydroartemisinin inhibited the growth of HeLa cells of human cervical cancer and showed a dose-dependent and time-dependent manner. Dihydroartemisinin (20 μmol/L) showed the radiosensitizing effects on HeLa cells, and the sensitizing enhancement ratio (SER) was 1.47. Dihydroartemisinin abrogated radiation-induced G 2 arrest of the tested HeLa cells, the G 2 ratio of medicine + radiation group dechned from 73.58% to 48.31%. Dihydroartemisinin enhanced the apoptosis of HeLa cells by X-irradiation, the apoptosis rates of medicine + radiation group significantly increased from 29.46%, 48.04%, 70.21% to 45.79%, 66.36% and 79.58%, respectively for 2, 4 and 6 Gy. Conclusions: Dihydroartemisinin could increase the radiosensitivity of HeLa cells of human cervical cancer. Abrogation of radiation-induced C 2 arrest could be part of the mechanism. (authors)

  7. 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.

  8. The α7-nicotinic acetylcholine receptor mediates the sensitivity of gastric cancer cells to taxanes.

    Science.gov (United States)

    Tu, Chao-Chiang; Huang, Chien-Yu; Cheng, Wan-Li; Hung, Chin-Sheng; Uyanga, Batzorig; Wei, Po-Li; Chang, Yu-Jia

    2016-04-01

    Gastric cancer is difficult to cure because most patients are diagnosed at an advanced disease stage. Systemic chemotherapy remains an important therapy for gastric cancer, but both progression-free survival and disease-free survival associated with various combination regimens are limited because of refractoriness and chemoresistance. Accumulating evidence has revealed that the homomeric α7-nicotinic acetylcholine receptor (A7-nAChR) promotes human gastric cancer by driving cancer cell proliferation, migration, and metastasis. Therefore, A7-nAChR may serve as a potential therapeutic target for gastric cancer. However, the role of A7-nAChR in taxane therapy for gastric cancer was unclear. Cells were subjected to A7-nAChR knockdown (A7-nAChR KD) using short interfering RNA (siRNA). The anti-proliferative effects of taxane were assessed via 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT), terminal deoxynucleotidyl transferase-mediated nick-end labeling (TUNEL), and cell cycle distribution assays. A7-nAChR-KD cells exhibited low resistance to docetaxel and paclitaxel treatment, as measured by the MTT assay. Following paclitaxel treatment, the proportion of apoptotic cells was higher among A7-nAChR-KD cells than among scrambled control cells, as measured by cell cycle distribution and TUNEL assays. Further molecular analyses showed a reduction in the pAKT levels and a dramatic increase in the Bad levels in paclitaxel-treated A7-nAChR-KD cells but not in scrambled control cells. Following paclitaxel treatment, the level of Bax was slightly increased in both cell populations, whereas Poly (ADP-ribose) polymerase (PARP) cleavage was increased only in A7-nAChR-KD cells. These findings indicate that A7-nAChR-KD cells are more sensitive to paclitaxel treatment. We conclude that A7-nAChR may be a key biomarker for assessing the chemosensitivity of gastric cancer cells to taxane.

  9. Loss of MLH1 sensitizes colon cancer cells to DNA-PKcs inhibitor KU60648.

    Science.gov (United States)

    Hinrichsen, Inga; Ackermann, Anne; Düding, Tonja; Graband, Annika; Filmann, Natalie; Plotz, Guido; Zeuzem, Stefan; Brieger, Angela

    2017-07-01

    Germline mutations of MLH1 are responsible for tumor generation in nearly 50% of patients with Lynch Syndrome, and around 15% of sporadic colorectal cancers show MLH1-deficiency due to promotor hypermethylation. Although these tumors are of lower aggressiveness the benefit for these patients from standard chemotherapy is still under discussion. Recently, it was shown that the sensitivity to the DNA-PKcs inhibitor KU60648 is linked to loss of the MMR protein MSH3. However, loss of MSH3 is rather secondary, as a consequence of MMR-deficiency, and frequently detectable in MLH1-deficient tumors. Therefore, we examined the expression of MLH1, MSH2, MSH6, and MSH3 in different MMR-deficient and proficient cell lines and determined their sensitivity to KU60648 by analyzing cell viability and survival. MLH1-dependent ability of double strand break (DSB) repair was monitored after irradiation via γH2AX detection. A panel of 12 colon cancer cell lines, two pairs of cells, where MLH1 knock down was compared to controls with the same genetic background, and one MLH1-deficient cell line where MLH1 was overexpressed, were included. In summary, we found that MLH1 and/or MSH3-deficient cells exhibited a significantly higher sensitivity to KU60648 than MMR-proficient cells and that overexpression of MLH1 in MLH1-deficient cells resulted in a decrease of cell sensitivity. KU60648 efficiency seems to be associated with reduced DSB repair capacity. Since the molecular testing of colon tumors for MLH1 expression is a clinical standard we believe that MLH1 is a much better marker and a greater number of patients would benefit from KU60648 treatment. © 2017 Wiley Periodicals, Inc.

  10. Resveratrol sensitization of DU145 prostate cancer cells to ionizing radiation is associated to ceramide increase.

    Science.gov (United States)

    Scarlatti, Francesca; Sala, Giusy; Ricci, Clara; Maioli, Claudio; Milani, Franco; Minella, Marco; Botturi, Marco; Ghidoni, Riccardo

    2007-08-08

    Radiotherapy is an established therapeutic modality for prostate cancer. Since it is well known that radiotherapy is limited due to its severe toxicity towards normal cells at high dose and minimal effect at low dose, the search for biological compounds that increase the sensitivity of tumors cells to radiation may improve the efficacy of therapy. Resveratrol, a natural antioxidant, was shown to inhibit carcinogenesis in animal models, and to block the process of tumor initiation and progression. The purpose of this study was to examine whether or not resveratrol can sensitize DU145, an androgen-independent human prostate cancer cell line, to ionizing radiation. We report here that DU145 cells are resistant to ionizing radiation-induced cell death, but pretreatment with resveratrol significantly enhances cell death. Resveratrol acts synergistically with ionizing radiation to inhibit cell survival in vitro. Resveratrol also potentiates ionizing radiation-induced ceramide accumulation, by promoting its de novo biosynthesis. This confirms ceramide as an effective mediator of the anticancer potential induced by resveratrol.

  11. 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.

  12. mTOR inhibition sensitizes ONC201-induced anti-colorectal cancer cell activity.

    Science.gov (United States)

    Jin, Zhe-Zhu; Wang, Wei; Fang, Di-Long; Jin, Yong-Jun

    2016-09-30

    We here tested the anti-colorectal cancer (CRC) activity by a first-in-class small molecule TRAIL inducer ONC201. The potential effect of mTOR on ONC201's actions was also examined. ONC201 induced moderate cytotoxicity against CRC cell lines (HT-29, HCT-116 and DLD-1) and primary human CRC cells. Significantly, AZD-8055, a mTOR kinase inhibitor, sensitized ONC201-induced cytotoxicity in CRC cells. Meanwhile, ONC201-induced TRAIL/death receptor-5 (DR-5) expression, caspase-8 activation and CRC cell apoptosis were also potentiated with AZD-8055 co-treatment. Reversely, TRAIL sequestering antibody RIK-2 or the caspase-8 specific inhibitor z-IETD-fmk attenuated AZD-8055 plus ONC201-induced CRC cell death. Further, mTOR kinase-dead mutation (Asp-2338-Ala) or shRNA knockdown significantly sensitized ONC201's activity in CRC cells, leading to profound cell death and apoptosis. On the other hand, expression of a constitutively-active S6K1 (T389E) attenuated ONC201-induced CRC cell apoptosis. For the mechanism study, we showed that ONC201 blocked Akt, but only slightly inhibited mTOR in CRC cells. Co-treatment with AZD-8055 also concurrently blocked mTOR activation. These results suggest that mTOR could be a primary resistance factor of ONC201 in CRC cells. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. A targeted enzyme approach to sensitization of tyrosine kinase inhibitor-resistant breast cancer cells.

    Science.gov (United States)

    Giordano, Courtney R; Mueller, Kelly L; Terlecky, Laura J; Krentz, Kendra A; Bollig-Fischer, Aliccia; Terlecky, Stanley R; Boerner, Julie L

    2012-10-01

    Gefitinib is an epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) of potential use in patients with breast cancer. Unfortunately, in clinical studies, gefitinib is often ineffective indicating that resistance to EGFR inhibitors may be a common occurrence in cancer of the breast. EGFR has been shown to be overexpressed in breast cancer, and in particular remains hyperphosphorylated in cell lines such as MDA-MB-468 that are resistant to EGFR inhibitors. Here, we investigate the cause of this sustained phosphorylation and the molecular basis for the ineffectiveness of gefitinib. We show that reactive oxygen species (ROS), known to damage cellular macromolecules and to modulate signaling cascades in a variety of human diseases including cancers, appear to play a critical role in mediating EGFR TKI-resistance. Furthermore, elimination of these ROS through use of a cell-penetrating catalase derivative sensitizes the cells to gefitinib. These results suggest a new approach for the treatment of TKI-resistant breast cancer patients specifically, the targeting of ROS and attendant downstream oxidative stress and their effects on signaling cascades. Copyright © 2012. Published by Elsevier Inc.

  14. Parallel screening of FDA-approved antineoplastic drugs for identifying sensitizers of TRAIL-induced apoptosis in cancer cells

    International Nuclear Information System (INIS)

    Taylor, David J; Parsons, Christine E; Han, Haiyong; Jayaraman, Arul; Rege, Kaushal

    2011-01-01

    Tumor Necrosis Factor-α Related Apoptosis Inducing Ligand (TRAIL) and agonistic antibodies to death receptor 4 and 5 are promising candidates for cancer therapy due to their ability to induce apoptosis selectively in a variety of human cancer cells, while demonstrating little cytotoxicity in normal cells. Although TRAIL and agonistic antibodies to DR4 and DR5 are considered safe and promising candidates in cancer therapy, many malignant cells are resistant to DR-mediated, TRAIL-induced apoptosis. In the current work, we screened a small library of fifty-five FDA and foreign-approved anti-neoplastic drugs in order to identify candidates that sensitized resistant prostate and pancreatic cancer cells to TRAIL-induced apoptosis. FDA-approved drugs were screened for their ability to sensitize TRAIL resistant prostate cancer cells to TRAIL using an MTT assay for cell viability. Analysis of variance was used to identify drugs that exhibited synergy with TRAIL. Drugs demonstrating the highest synergy were selected as leads and tested in different prostate and pancreatic cancer cell lines, and one immortalized human pancreatic epithelial cell line. Sequential and simultaneous dosing modalities were investigated and the annexin V/propidium iodide assay, in concert with fluorescence microscopy, was employed to visualize cells undergoing apoptosis. Fourteen drugs were identified as having synergy with TRAIL, including those whose TRAIL sensitization activities were previously unknown in either prostate or pancreatic cancer cells or both. Five leads were tested in additional cancer cell lines of which, doxorubicin, mitoxantrone, and mithramycin demonstrated synergy in all lines. In particular, mitoxantrone and mithramycin demonstrated significant synergy with TRAIL and led to reduction of cancer cell viability at concentrations lower than 1 μM. At these low concentrations, mitoxantrone demonstrated selectivity toward malignant cells over normal pancreatic epithelial cells

  15. Parallel screening of FDA-approved antineoplastic drugs for identifying sensitizers of TRAIL-induced apoptosis in cancer cells

    Directory of Open Access Journals (Sweden)

    Taylor David J

    2011-11-01

    Full Text Available Abstract Background Tumor Necrosis Factor-α Related Apoptosis Inducing Ligand (TRAIL and agonistic antibodies to death receptor 4 and 5 are promising candidates for cancer therapy due to their ability to induce apoptosis selectively in a variety of human cancer cells, while demonstrating little cytotoxicity in normal cells. Although TRAIL and agonistic antibodies to DR4 and DR5 are considered safe and promising candidates in cancer therapy, many malignant cells are resistant to DR-mediated, TRAIL-induced apoptosis. In the current work, we screened a small library of fifty-five FDA and foreign-approved anti-neoplastic drugs in order to identify candidates that sensitized resistant prostate and pancreatic cancer cells to TRAIL-induced apoptosis. Methods FDA-approved drugs were screened for their ability to sensitize TRAIL resistant prostate cancer cells to TRAIL using an MTT assay for cell viability. Analysis of variance was used to identify drugs that exhibited synergy with TRAIL. Drugs demonstrating the highest synergy were selected as leads and tested in different prostate and pancreatic cancer cell lines, and one immortalized human pancreatic epithelial cell line. Sequential and simultaneous dosing modalities were investigated and the annexin V/propidium iodide assay, in concert with fluorescence microscopy, was employed to visualize cells undergoing apoptosis. Results Fourteen drugs were identified as having synergy with TRAIL, including those whose TRAIL sensitization activities were previously unknown in either prostate or pancreatic cancer cells or both. Five leads were tested in additional cancer cell lines of which, doxorubicin, mitoxantrone, and mithramycin demonstrated synergy in all lines. In particular, mitoxantrone and mithramycin demonstrated significant synergy with TRAIL and led to reduction of cancer cell viability at concentrations lower than 1 μM. At these low concentrations, mitoxantrone demonstrated selectivity toward

  16. [Astragalus polysaccharide may increase sensitivity of cervical cancer HeLa cells to cisplatin by regulating cell autophagy].

    Science.gov (United States)

    Zhai, Qiu-Li; Hu, Xiang-Dan; Xiao, Jing; Yu, Dong-Qing

    2018-02-01

    This study aimed to investigate the possible sensitivity of Astragalus polysaccharides, in order to improve the chemosensitivity of cervical cancer HeLa cells to cisplatin by regulating the cell autophagy, and explore its possible mechanism. In this study, HeLa cells were divided into control group, cisplatin group, Astragalus polysaccharide group, and Astragalus polysaccharide combined with cisplatin group. MTT assay was used to detect the proliferation of cervical cancer HeLa cells. Flow cytometry was used to detect the apoptosis and cycle of HeLa cells in each experimental group. RT-PCR was used to detect the mRNA expression of autophagy-related proteins beclin1, LC3Ⅱ and p62. The expression levels of autophagy-related proteins beclin1, LC3Ⅱ, LC3Ⅰ and p62 were detected by WB method. MTT results showed that compared with the control group, the proliferation of HeLa cells was significantly inhibited in each administration group( P HeLa cells was significantly increased( P HeLa cells to cisplatin by regulating the cell autophagy. Its possible mechanism of action is correlated with the up-regulation of autophagy-related proteins beclin1, the promote the conversion from LC3Ⅰ to LC3Ⅱ, the down-regulation of labeled protein p62, and the enhancement of HeLa cell autophagic activity, thereby increasing the sensitivity of HeLa cells to cisplatin chemotherapy. Copyright© by the Chinese Pharmaceutical Association.

  17. 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.

  18. 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.

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

    Science.gov (United States)

    Storm, Petter; Puthia, Manoj Kumar; Aits, Sonja; Urbano, Alexander; Northen, Trent; Powers, Scott; Bowen, Ben; Chao, Yinxia; Reindl, Wolfgang; Lee, Do Yup; Sullivan, Nancy Liu; Zhang, Jianping; Trulsson, Maria; Yang, Henry; Watson, James; Svanborg, Catharina

    2014-01-01

    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 inhibition, proteomic and metabolomic technology we identified the c-Myc oncogene as one essential determinant of HAMLET sensitivity. Increased c-Myc expression levels promoted the 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, the HAMLET sensitivity was modified by the glycolytic state of the tumor cells. Glucose deprivation sensitized tumor cells to HAMLET-induced cell death and in the shRNA screen Hexokinase 1, PFKFB1 and HIF1α modified HAMLET sensitivity. Hexokinase 1 was shown to bind HAMLET in a protein array containing approximately 8000 targets and Hexokinase activity decreased within 15 minutes of HAMLET treatment, prior to morphological signs of tumor cell death. In parallel, HAMLET triggered rapid metabolic paralysis in carcinoma cells. The glycolytic machinery was modified and glycolysis was shifted towards the pentose phosphate pathway. Tumor cells were also shown to contain large amounts of oleic acid and its derivatives already after 15 minutes. 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. PMID:21643007

  20. 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.

  1. The effect of troglitazone on thermal sensitivity in uterine cervix cancer cells

    International Nuclear Information System (INIS)

    Lee, Ji Hye; Kim, Won Dong; Park, Woo Yoon

    2010-01-01

    Troglitazone (TRO), a PPAR-γ agonist, can reduce heat shock protein (HSP) 70 and increase the antioxidant enzymes, such as superoxide dismutase (SOD) and catalase, which might affect thermal sensitivity. Here, we investigated whether TRO modifies thermal sensitivity in uterine cervical cancer cells, which is most commonly treated by hyperthermia (HT). HeLa cells were treated with 5μM TRO for 24 hours before HT at 42 .deg. C for 1 hour. Cell survival was analyzed by clonogenic assay. The expression of HSPs was analyzed by Western blot. SOD and catalase activity was measured and reactive oxygen species (ROS) was measured using 2',7'-dichlorofluorescin diacetate and dihydroethidium. The decreased cell survival by HT was increased by preincubation with TRO before HT. Expression of HSP 70 was increased by HT however, it was not decreased by preincubation with TRO before HT. The decreased Bcl-2 expression by HT was increased by preincubation with TRO. SOD and catalase activity was increased by 1.2 and 1.3 times, respectively with TRO. Increased ROS by HT was decreased by preincubation with TRO. TRO decreases thermal sensitivity through increased SOD and catalase activity, as well as scavenging ROS in HeLa cells.

  2. Sildenafil (Viagra) sensitizes prostate cancer cells to doxorubicin-mediated apoptosis through CD95

    Science.gov (United States)

    Das, Anindita; Durrant, David; Mitchell, Clint; Dent, Paul; Batra, Surinder K.; Kukreja, Rakesh C.

    2016-01-01

    We previously reported that Sildenafil enhances apoptosis and antitumor efficacy of doxorubicin (DOX) while attenuating its cardiotoxic effect in prostate cancer. In the present study, we investigated the mechanism by which sildenafil sensitizes DOX in killing of prostate cancer (PCa) cells, DU145. The death receptor Fas (APO-1 or CD95) induces apoptosis in many carcinoma cells, which is negatively regulated by anti-apoptotic molecules such as FLIP (Fas-associated death domain (FADD) interleukin-1-converting enzyme (FLICE)-like inhibitory protein). Co-treatment of PCa cells with sildenafil and DOX for 48 hours showed reduced expression of both long and short forms of FLIP (FLIP-L and -S) as compared to individual drug treatment. Over-expression of FLIP-s with an adenoviral vector attentuated the enhanced cell-killing effect of DOX and sildenafil. Colony formation assays also confirmed that FLIP-S over-expression inhibited the DOX and sildenafil-induced synergistic killing effect as compared to the cells infected with an empty vector. Moreover, siRNA knock-down of CD95 abolished the effect of sildenafil in enhancing DOX lethality in cells, but had no effect on cell killing after treatment with a single agent. Sildenafil co-treatment with DOX inhibited DOX-induced NF-κB activity by reducing phosphorylation of IκB and nuclear translocation of the p65 subunit, in addition to down regulation of FAP-1 (Fas associated phosphatase-1, a known inhibitor of CD95-mediated apoptosis) expression. This data provides evidence that the CD95 is a key regulator of sildenafil and DOX mediated enhanced cell death in prostate cancer. PMID:26716643

  3. Novel targets for sensitizing breast cancer cells to TRAIL-induced apoptosis with siRNA delivery.

    Science.gov (United States)

    Thapa, Bindu; Bahadur Kc, Remant; Uludağ, Hasan

    2018-02-01

    Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) induces apoptosis in variety of cancer cells without affecting most normal cells, which makes it a promising agent for cancer therapy. However, TRAIL therapy is clinically not effective due to resistance induction. To identify novel regulators of TRAIL that can aid in therapy, protein targets whose silencing sensitized breast cancer cells against TRAIL were screened with an siRNA library against 446 human apoptosis-related proteins in MDA-231 cells. Using a cationic lipopolymer (PEI-αLA) for delivery of library members, 16 siRNAs were identified that sensitized the TRAIL-induced death in MDA-231 cells. The siRNAs targeting BCL2L12 and SOD1 were further evaluated based on the novelty and their ability to sensitize TRAIL induced cell death. Silencing both targets sensitized TRAIL-mediated cell death in MDA-231 cells as well as TRAIL resistant breast cancer cells, MCF-7. Combination of TRAIL and siRNA silencing BCL2L12 had no effect in normal human umbilical vein cells and human bone marrow stromal cell. The silencing of BCL2L12 and SOD1 enhanced TRAIL-mediated apoptosis in MDA-231 cells via synergistically activating capsase-3 activity. Hence, here we report siRNAs targeting BCL2L12 and SOD1 as a novel regulator of TRAIL-induced cell death in breast cancer cells, providing a new approach for enhancing TRAIL therapy for breast cancer. The combination of siRNA targeting BCL2L12 and TRAIL can be a highly effective synergistic pair in breast cancer cells with minimal effect on the non-transformed cells. © 2017 UICC.

  4. Radio-sensitization of WRN helicase deficient cancer cells by targeting homologous recombination pathway

    International Nuclear Information System (INIS)

    Gupta, Pooja; Saha, Bhaskar; Patro, Birija Sankar; Chattopadhyay, Subrata

    2016-01-01

    Ionizing radiation (IR) induced DNA double-strand breaks (DSBs) are primarily repaired by non-homologous end joining (NHEJ). However, it is well established that a subset DSBs which are accumulated in IR-induced G2 phase are dependent on homologous recombination (HR). DNA repair deficient tumor cells have been shown to accumulate high levels of DNA damage. Consequently, these cells become hyperdependent on DNA damage response pathways, including the CHK1-kinase-mediated HR-repair. These observations suggest that DNA repair deficient tumors should exhibit increased radio-sensitivity under HR inhibition. Genetic defects leading to functional loss of werner (WRN) protein is associated with genomic instability and increased cancer incidence. WRN function is known to be abrogated in several human cancer cells due to hypermethylation of CpGisland-promoter and transcriptional silencing of WRN gene. In the current investigation, using isogenic pairs of cell lines differing only in the WRN function, we showed that WRN-deficient cell lines were hyper-radiosensitive to CHK1 pharmacologic inhibition. Here, we found that unrepaired DSB was drastically increased in WRN-deficient cells vis-à-vis WRN-proficient cells in response to IR and CHK1 inhibitor (CHK1i). Our results revealed a marginal role of NHEJ pathway accountable for the radio-sensitivity of WRN-deficient cells. Interestingly, silencing CTIP, a HR protein required for RAD51 loading, significantly abrogated the CHK1i-mediated radiosensitivity in WRN-deficient cells. Silencing of WRN or CTIP individually led to no significant difference in the extent of DNA end resection, as required during HR pathway. Imperatively, our results revealed that WRN and CTIP together play a complementary role in executing DNA end resection during HR-mediated repair of IR induced DSBs. Altogether, our data indicated that inhibition of IR-induced HR pathway at RAD51 loading, but not at DSB end resection, make the WRN-deficient cancer cells

  5. Study of radiation sensitization of artesunate on human HeLa cells of cervical cancer

    International Nuclear Information System (INIS)

    Ji Rong; Cao Jianping; Chen Xialin; Zhu Wei; Jiang Qing; Pan Chunyan; Zhou Yuanyuan; Feng Yang; Peng Xiaomei; Liu Yang; Fan Saijun

    2010-01-01

    Objective: To investigate the radiosensitizing effects of artesunate on human HeLa cells of cervical cancer in vitro. Methods: Hela cells irradiated with 60 Co γ-rays. The dose rate was 0.635 Gy/min and the radiation dose was 0, 1, 2, 4, 6 Gy, respectively. The anti-proliferation activities of artesunate on HeLa cells were evaluated with MTT assay, to determine the most appropriate drug concentration. The effect of radiosensitivity was observed by using clonogenic assay. The single-hit multi-target model was used to plot the HeLa cell's dose-survival curve, to calculate mean lethal dose, quasi-threshold dose and sensitization enhancement rate, and to evaluate its radiosensitization effect. The apoptosis was analyzed with flow cytometry (FCM) to further test the radiation sensitization of artesunate on HeLa cells. Results: The inhibition of artesunate on HeLa cells increased with concentration. In radiation group, the cell cloning efficiency were 91.67%, 82.02%, 58.06%, 25.01%, respectively, and in artesunate (2.0 μmol/L) + radiation group, the cell cloning efficiency were 74.93%, 60.53%, 22.38%, 5.05%. In radiation group and artesunate (2.0 μmol/L) + radiation group, the mean lethal dose (D 0 ) was 2.95 and 2.07 Gy, respectively, while the qusai-threshold dose (D q ) were 2.01 and 1.24 Gy, respectively, and SER was 1.43. Compared with 2 and 6 Gy radiation group, the apoptosis rate of drug + radiation group increased from 12.26%, 40.08% to 22.71%, 59.92. Conclusions: The inhibiting effect of artesunate on HeLa cells is concentration-dependent. Artesunate has radiosensitizing effect on HeLa cells in vitro. (authors)

  6. Context Sensitive Modeling of Cancer Drug Sensitivity.

    Directory of Open Access Journals (Sweden)

    Bo-Juen Chen

    Full Text Available Recent screening of drug sensitivity in large panels of cancer cell lines provides a valuable resource towards developing algorithms that predict drug response. Since more samples provide increased statistical power, most approaches to prediction of drug sensitivity pool multiple cancer types together without distinction. However, pan-cancer results can be misleading due to the confounding effects of tissues or cancer subtypes. On the other hand, independent analysis for each cancer-type is hampered by small sample size. To balance this trade-off, we present CHER (Contextual Heterogeneity Enabled Regression, an algorithm that builds predictive models for drug sensitivity by selecting predictive genomic features and deciding which ones should-and should not-be shared across different cancers, tissues and drugs. CHER provides significantly more accurate models of drug sensitivity than comparable elastic-net-based models. Moreover, CHER provides better insight into the underlying biological processes by finding a sparse set of shared and type-specific genomic features.

  7. Exosomes decrease sensitivity of breast cancer cells to adriamycin by delivering microRNAs.

    Science.gov (United States)

    Mao, Ling; Li, Jian; Chen, Wei-Xian; Cai, Yan-Qin; Yu, Dan-Dan; Zhong, Shan-Liang; Zhao, Jian-Hua; Zhou, Jian-Wei; Tang, Jin-Hai

    2016-04-01

    While adriamycin (adr) offers improvement in survival for breast cancer (BCa) patients, unfortunately, drug resistance is almost inevitable. Mounting evidence suggests that exosomes act as a vehicle for genetic cargo and constantly shuttle biologically active molecules including microRNAs (miRNAs) between heterogeneous populations of tumor cells, engendering a resistance-promoting niche for cancer progression. Our recent study showed that exosomes from docetaxel-resistance BCa cells could modulate chemosensitivity by delivering miRNAs. Herein, we expand on our previous finding and explore the relevance of exosome-mediated miRNA delivery in resistance transmission of adr-resistant BCa sublines. We now demonstrated the selective packing of miRNAs within the exosomes (A/exo) derived from adr-resistant BCa cells. The highly expressed miRNAs in A/exo were significantly increased in recipient fluorescent sensitive cells (GFP-S) after A/exo incorporation. Gene ontology analysis of predicted targets showed that the top 30 most abundant miRNAs in A/exo were involved in crucial biological processes. Moreover, A/exo not only loaded miRNAs for its production and release but also carried miRNAs associated with Wnt signaling pathway. Furthermore, A/exo co-culture assays indicated that miRNA-containing A/exo was able to increase the overall resistance of GFP-S to adr exposure and regulate gene levels in GFP-S. Our results reinforce our earlier reports that adr-resistant BCa cells could manipulate a more deleterious microenvironment and transmit resistance capacity through altering gene expressions in sensitive cells by transferring specific miRNAs contained within exosomes.

  8. Targeting DNA repair with PNKP inhibition sensitizes radioresistant prostate cancer cells to high LET radiation.

    Directory of Open Access Journals (Sweden)

    Pallavi Srivastava

    Full Text Available High linear energy transfer (LET radiation or heavy ion such as carbon ion radiation is used as a method for advanced radiotherapy in the treatment of cancer. It has many advantages over the conventional photon based radiotherapy using Co-60 gamma or high energy X-rays from a Linear Accelerator. However, charged particle therapy is very costly. One way to reduce the cost as well as irradiation effects on normal cells is to reduce the dose of radiation by enhancing the radiation sensitivity through the use of a radiomodulator. PNKP (polynucleotide kinase/phosphatase is an enzyme which plays important role in the non-homologous end joining (NHEJ DNA repair pathway. It is expected that inhibition of PNKP activity may enhance the efficacy of the charged particle irradiation in the radioresistant prostate cancer cell line PC-3. To test this hypothesis, we investigated cellular radiosensitivity by clonogenic cell survival assay in PC-3 cells.12Carbon ion beam of62 MeVenergy (equivalent 5.16 MeV/nucleon and with an entrance LET of 287 kev/μm was used for the present study. Apoptotic parameters such as nuclear fragmentation and caspase-3 activity were measured by DAPI staining, nuclear ladder assay and colorimetric caspase-3method. Cell cycle arrest was determined by FACS analysis. Cell death was enhanced when carbon ion irradiation is combined with PNKPi (PNKP inhibitor to treat cells as compared to that seen for PNKPi untreated cells. A low concentration (10μM of PNKPi effectively radiosensitized the PC-3 cells in terms of reduction of dose in achieving the same survival fraction. PC-3 cells underwent significant apoptosis and cell cycle arrest too was enhanced at G2/M phase when carbon ion irradiation was combined with PNKPi treatment. Our findings suggest that combined treatment of carbon ion irradiation and PNKP inhibition could enhance cellular radiosensitivity in a radioresistant prostate cancer cell line PC-3. The synergistic effect of PNKPi

  9. Inhibition of Glutathione and Thioredoxin Metabolism Enhances Sensitivity to Perifosine in Head and Neck Cancer Cells

    Directory of Open Access Journals (Sweden)

    Andrean L. Simons

    2009-01-01

    Full Text Available The hypothesis that the Akt inhibitor, perifosine (PER, combined with inhibitors of glutathione (GSH and thioredoxin (Trx metabolism will induce cytotoxicity via metabolic oxidative stress in human head and neck cancer (HNSCC cells was tested. PER induced increases in glutathione disulfide (%GSSG in FaDu, Cal-27, and SCC-25 HNSCCs as well as causing significant clonogenic cell killing in FaDu and Cal-27, which was suppressed by simultaneous treatment with N-acetylcysteine (NAC. An inhibitor of GSH synthesis, buthionine sulfoximine (BSO, sensitized Cal-27 and SCC-25 cells to PER-induced clonogenic killing as well as decreased total GSH and increased %GSSG. Additionally, inhibition of thioredoxin reductase activity (TrxRed with auranofin (AUR was able to induce PER sensitization in SCC-25 cells that were initially refractory to PER. These results support the conclusion that PER induces oxidative stress and clonogenic killing in HNSCC cells that is enhanced with inhibitors of GSH and Trx metabolism.

  10. Inhibition of iron uptake is responsible for differential sensitivity to V-ATPase inhibitors in several cancer cell lines.

    Directory of Open Access Journals (Sweden)

    Sarah Straud

    2010-07-01

    Full Text Available Many cell lines derived from tumors as well as transformed cell lines are far more sensitive to V-ATPase inhibitors than normal counterparts. The molecular mechanisms underlying these differences in sensitivity are not known. Using global gene expression data, we show that the most sensitive responses to HeLa cells to low doses of V-ATPase inhibitors involve genes responsive to decreasing intracellular iron or decreasing cholesterol and that sensitivity to iron uptake is an important determinant of V-ATPase sensitivity in several cancer cell lines. One of the most sensitive cell lines, melanoma derived SK-Mel-5, over-expresses the iron efflux transporter ferroportin and has decreased expression of proteins involved in iron uptake, suggesting that it actively suppresses cytoplasmic iron. SK-Mel-5 cells have increased production of reactive oxygen species and may be seeking to limit additional production of ROS by iron.

  11. Cytotoxicity of South-African medicinal plants towards sensitive and multidrug-resistant cancer cells.

    Science.gov (United States)

    Saeed, Mohamed E M; Meyer, Marion; Hussein, Ahmed; Efferth, Thomas

    2016-06-20

    Traditional medicine plays a major role for primary health care worldwide. Cancer belongs to the leading disease burden in industrialized and developing countries. Successful cancer therapy is hampered by the development of resistance towards established anticancer drugs. In the present study, we investigated the cytotoxicity of 29 extracts from 26 medicinal plants of South-Africa against leukemia cell lines, most of which are used traditionally to treat cancer and related symptoms. We have investigated the plant extracts for their cytotoxic activity towards drug-sensitive parental CCRF-CEM leukemia cells and their multidrug-resistant P-glycoprotein-overexpressing subline, CEM/ADR5000 by means of the resazurin assay. A panel of 60 NCI tumor cell lines have been investigated for correlations between selected phytochemicals from medicinal plants and the expression of resistance-conferring genes (ABC-transporters, oncogenes, tumor suppressor genes). Seven extracts inhibited both cell lines (Acokanthera oppositifolia, Hypoestes aristata, Laurus nobilis, Leonotis leonurus, Plectranthus barbatus, Plectranthus ciliates, Salvia apiana). CEM/ADR5000 cells exhibited a low degree of cross-resistance (3.35-fold) towards the L. leonurus extract, while no cross-resistance was observed to other plant extracts, although CEM/ADR5000 cells were highly resistant to clinically established drugs. The log10IC50 values for two out of 14 selected phytochemicals from these plants (acovenoside A and ouabain) of 60 tumor cell lines were correlated to the expression of ABC-transporters (ABCB1, ABCB5, ABCC1, ABCG2), oncogenes (EGFR, RAS) and tumor suppressors (TP53). Sensitivity or resistance of the cell lines were not statistically associated with the expression of these genes, indicating that multidrug-resistant, refractory tumors expressing these genes may still respond to acovenoside A and ouabain. The bioactivity of South African medicinal plants may represent a basis for the development

  12. 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.

  13. Specific repression of mutant K-RAS by 10-23 DNAzyme: Sensitizing cancer cell to anti-cancer therapies

    International Nuclear Information System (INIS)

    Yu, S.-H.; Wang, T.-H.; Au, L.-C.

    2009-01-01

    Point mutations of the Ras family are frequently found in human cancers at a prevalence rate of 30%. The most common mutation K-Ras(G12V), required for tumor proliferation, survival, and metastasis due to its constitutively active GTPase activity, has provided an ideal target for cancer therapy. 10-23 DNAzyme, an oligodeoxyribonucleotide-based ribonuclease consisting of a 15-nucleotide catalytical domain flanked by two target-specific complementary arms, has been shown to effectively cleave the target mRNA at purine-pyrimidine dinucleotide. Taking advantage of this specific property, 10-23 DNAzyme was designed to cleave mRNA of K-Ras(G12V)(GGU → GUU) at the GU dinucleotide while left the wild-type (WT) K-Ras mRNA intact. The K-Ras(G12V)-specific 10-23 DNAzyme was able to reduce K-Ras(G12V) at both mRNA and protein levels in SW480 cell carrying homozygous K-Ras(G12V). No effect was observed on the WT K-Ras in HEK cells. Although K-Ras(G12V)-specific DNAzymes alone did not inhibit proliferation of SW480 or HEK cells, pre-treatment of this DNAzyme sensitized the K-Ras(G12V) mutant cells to anti-cancer agents such as doxorubicin and radiation. These results offer a potential of using allele-specific 10-23 DNAzyme in combination with other cancer therapies to achieve better effectiveness on cancer treatment.

  14. Multiple kinase pathways involved in the different de novo sensitivity of pancreatic cancer cell lines to 17-AAG.

    Science.gov (United States)

    Liu, Heping; Zhang, Ti; Chen, Rong; McConkey, David J; Ward, John F; Curley, Steven A

    2012-07-01

    17-Allylamino-17-demethoxygeldanamycin (17-AAG) specifically targets heat shock protein (HSP)90 and inhibits its chaperoning functions for multiple kinases involved in cancer cell growth and survival. To select responsive patients, the molecular mechanisms underlying the sensitivity of cancer cells to 17-AAG must be elucidated. We used cytotoxicity assays and Western blotting to explore the effects of 17-AAG and sorafenib on cell survival and expression of multiple kinases in the pancreatic cancer cell lines AsPC-1 and Panc-1. Gene cloning and transfection, siRNA silencing, and immunohistochemistry were used to evaluate the effects of mutant p53 protein on 17-AAG sensitivity. AsPC-1 and Panc-1 responded differently to 17-AAG, with half maximal inhibitory concentration (IC(50)) values of 0.12 and 3.18 μM, respectively. Comparable expression of HSP90, HSP70, and HSP27 was induced by 17-AAG in AsPC-1 and Panc-1 cells. P-glycoprotein and mutant p53 did not affect 17-AAG sensitivity in these cell lines. Multiple kinases are more sensitive to HSP90 inhibition in AsPC-1 than in Panc-1 cells. After 17-AAG treatment, p-Bad (S112) decreased in AsPC-1 cells and increased in Panc-1 cells. Sorafenib markedly increased p-Akt, p-ERK1/2, p-GSK-3β, and p-S6 in both cell lines. Accordingly, 17-AAG and sorafenib acted antagonistically in AsPC-1 and Panc-1 cells, except at high concentrations in AsPC-1 cells. Differential inhibition of multiple kinases is responsible for the different de novo sensitivity of AsPC-1 and Panc-1 cells to HSP90 inhibition. P-glycoprotein and mutant p53 protein did not play a role in the sensitivity of pancreatic cancer cells to 17-AAG. Copyright © 2012 Elsevier Inc. All rights reserved.

  15. 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.

  16. The human cyclin B1 protein modulates sensitivity of DNA mismatch repair deficient prostate cancer cell lines to alkylating agents.

    Science.gov (United States)

    Rasmussen, L J; Rasmussen, M; Lützen, A; Bisgaard, H C; Singh, K K

    2000-05-25

    DNA damage caused by alkylating agents results in a G2 checkpoint arrest. DNA mismatch repair (MMR) deficient cells are resistant to killing by alkylating agents and are unable to arrest the cell cycle in G2 phase after alkylation damage. We investigated the response of two MMR-deficient prostate cancer cell lines DU145 and LNCaP to the alkylating agent MNNG. Our studies reveal that DU145 cancer cells are more sensitive to killing by MNNG than LNCaP. Investigation of the underlying reasons for lower resistance revealed that the DU145 cells contain low endogenous levels of cyclin B1. We provide direct evidence that the endogenous level of cyclin B1 modulates the sensitivity of MMR-deficient prostate cancer cells to alkylating agents.

  17. ATM inhibition induces synthetic lethality and enhances sensitivity of PTEN-deficient breast cancer cells to cisplatin.

    Science.gov (United States)

    Li, Ke; Yan, Huaying; Guo, Wenhao; Tang, Mei; Zhao, Xinyu; Tong, Aiping; Peng, Yong; Li, Qintong; Yuan, Zhu

    2018-05-01

    PTEN deficiency often causes defects in DNA damage repair. Currently, effective therapies for breast cancer are lacking. ATM is an attractive target for cancer treatment. Previous studies suggested a synthetic lethality between PTEN and PARP. However, the synthetically lethal interaction between PTEN and ATM in breast cancer has not been reported. Moreover, the mechanism remains elusive. Here, using KU-60019, an ATM kinase inhibitor, we investigated ATM inhibition as a synthetically lethal strategy to target breast cancer cells with PTEN defects. We found that KU-60019 preferentially sensitizes PTEN-deficient MDA-MB-468 breast cancer cells to cisplatin, though it also slightly enhances sensitivity of PTEN wild-type breast cancer cells. The increased cytotoxic sensitivity is associated with apoptosis, as evidenced by flow cytometry and PARP cleavage. Additionally, the increase of DNA damage accumulation due to the decreased capability of DNA repair, as indicated by γ-H2AX and Rad51 foci, also contributed to this selective cytotoxicity. Mechanistically, compared with PTEN wild-type MDA-MB-231 cells, PTEN-deficient MDA-MB-468 cells have lower level of Rad51, higher ATM kinase activity, and display the elevated level of DNA damage. Moreover, these differences could be further enlarged by cisplatin. Our findings suggest that ATM is a promising target for PTEN-defective breast cancer. Copyright © 2018 Elsevier Inc. All rights reserved.

  18. ER-Stress-Induced Differentiation Sensitizes Colon Cancer Stem Cells to Chemotherapy

    NARCIS (Netherlands)

    Wielenga, Mattheus C. B.; Colak, Selcuk; Heijmans, Jarom; van Lidth de Jeude, Jooske F.; Rodermond, Hans M.; Paton, James C.; Paton, Adrienne W.; Vermeulen, Louis; Medema, Jan Paul; van den Brink, Gijs R.

    2015-01-01

    Colon cancer stem cells (colon-CSCs) are more resistant to conventional chemotherapy than differentiated cancer cells. This subset of therapy refractory cells is therefore believed to play an important role in post-therapeutic tumor relapse. In order to improve the rate of sustained response to

  19. Widespread molecular patterns associated with drug sensitivity in breast cancer cell lines, with implications for human tumors.

    Directory of Open Access Journals (Sweden)

    Chad J Creighton

    Full Text Available BACKGROUND: Recent landmark studies have profiled cancer cell lines for molecular features, along with measuring the corresponding growth inhibitory effects for specific drug compounds. These data present a tool for determining which subsets of human cancer might be more responsive to particular drugs. To this end, the NCI-DREAM-sponsored DREAM7: Drug Sensitivity Prediction Challenge (sub-challenge 1 set out to predict the sensitivities of 18 breast cancer cell lines to 31 previously untested compounds, on the basis of molecular profiling data and a training subset of cell lines. METHODS AND RESULTS: With 47 teams submitting blinded predictions, team Creighton scored third in terms of overall accuracy. Team Creighton's method was simple and straightforward, incorporated multiple expression data types (RNA-seq, gene array, RPPA, and incorporated all profiled features (not only the "best" predictive ones. As an extension of the approach, cell line data, from public datasets of expression profiling coupled with drug sensitivities (Barretina, Garnett, Heiser were used to "predict" the drug sensitivities in human breast tumors (using data from The Cancer Genome Atlas. Drug sensitivity correlations within human breast tumors showed differences by expression-based subtype, with many associations in line with the expected (e.g. Lapatinib sensitivity in HER2-enriched cancers and others inviting further study (e.g. relative resistance to PI3K inhibitors in basal-like cancers. CONCLUSIONS: Molecular patterns associated with drug sensitivity are widespread, with potentially hundreds of genes that could be incorporated into making predictions, as well as offering biological clues as to the mechanisms involved. Applying the cell line patterns to human tumor data may help generate hypotheses on what tumor subsets might be more responsive to therapies, where multiple cell line datasets representing various drugs may be used, in order to assess consistency of

  20. Syringic acid from Tamarix aucheriana possesses antimitogenic and chemo-sensitizing activities in human colorectal cancer cells.

    Science.gov (United States)

    Abaza, Mohamed-Salah; Al-Attiyah, Raja'a; Bhardwaj, Radhika; Abbadi, Ghaneim; Koyippally, Mathew; Afzal, Mohammad

    2013-09-01

    For its variety of biological activities, Tamarix aucheriana (Decne.) Baum. (Tamaricaceae) has an extensive history as a traditional Arab medicine. Antimitogenic and chemo-sensitizing activities of syringic acid (SA) were studied against human colorectal cancer. Chromatographic and spectral data were used for the isolation and identification of SA. MTT, flow cytometry, in vitro invasion and angiogenesis assays, fluoremetry, ELISA and Real Time qPCR were used to test antimitogenic and chemo-sensitizing activities of SA, cell cycle, apoptosis, proteasome and NFκB-DNA-binding activities, cancer cell invasion and angiogenesis, and expression of cell cycle/apoptosis-related genes. SA showed a time- and dose-dependent (IC₅₀ = 0.95-1.2 mg mL⁻¹) antimitogenic effect against cancer cells with little cytotoxicity on normal fibroblasts (≤20%). SA-altered cell cycle (S/G2-M or G1/G2-M phases) in a time-dependent manner, induced apoptosis, inhibited DNA-binding activity of NFκB (p ≤ 0.0001), chymotrypsin-like/PGPH (peptidyl-glutamyl peptide-hydrolyzing) (p ≤ 0.0001) and the trypsin-like (p ≤ 0.002) activities of 26S proteasome and angiogenesis. SA also differentially sensitized cancer cells to standard chemotherapies with a marked increase in their sensitivity to camptothecin (500-fold), 5FU (20,000-fold), doxorubicin (210-fold), taxol (3134-fold), vinblastine (1000-fold), vincristine (130-fold) and amsacrine (107-fold) compared to standard drugs alone. SA exerted its chemotherapeutic and chemo-sensitizing effects through an array of mechanisms including cell-cycle arrest, apoptosis induction, inhibition of cell proliferation, cell migration, angiogenesis, NFκB DNA-binding and proteasome activities. These results demonstrate the potential of SA as an antimitogenic and chemo-sensitizing agent for human colorectal cancer.

  1. SU-F-T-678: Clotrimazole Sensitizes MCF-7 Breast Cancer Cell Line to Radiation

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, L; Tambasco, M [San Diego State University, San Diego, CA (United States)

    2016-06-15

    Purpose: To study the effects of Clotrimazole (CLT) on radiosensitivity of MCF-7 Cells in correlation to detachment of Hexokinase II from the Voltage Dependent Anion Channel on the outer membrane of the mitochondria. Apoptotic fractions were also analyzed in relation to the detachment of Hexokinase. Methods: This study focused on the mammary adenocarcinoma cell line, MCF-7. Colony forming assays were used to analyze radiosensitization by CLT. Flow cytometry methods were used to analyze apoptotic vs necrotic fractions after treatment with CLT. Spectrophotometery was used to analyze the mitochondrial bound and soluble fraction of Hexokinase by means of relative enzymatic activity. Results: Our preliminary data have shown that CLT sensitizes MCF-7 cells to radiation in a dose and incubation time dependent manner up. We have also demonstrated that there are two radiosensitizing periods in MCF-7 cells with the first corresponding to the cycle arrest after 24 hours observed in other cell lines. The second radiosensitizing period occurs with incubation in CLT after irradiation which reaches maximum effect around 24 hours of incubation time. Preliminary data from our Hexokinase detachment assay show a factor of two increase in the ratio of unbound to bound Hexokinase when comparing incubation for 24 hours in media containing 0 and 20 µM CLT. Conclusion: This study and others indicate CLT as a possible radiosensitizing agent in cancer therapies. While CLT itself shows toxicity to the liver in high doses, this study further demonstrates that disruption of the Warburg Effect and unbinding of mitochondrial bound Hexokinase as a possible pathway for cancer treatment.

  2. SU-F-T-678: Clotrimazole Sensitizes MCF-7 Breast Cancer Cell Line to Radiation

    International Nuclear Information System (INIS)

    Garcia, L; Tambasco, M

    2016-01-01

    Purpose: To study the effects of Clotrimazole (CLT) on radiosensitivity of MCF-7 Cells in correlation to detachment of Hexokinase II from the Voltage Dependent Anion Channel on the outer membrane of the mitochondria. Apoptotic fractions were also analyzed in relation to the detachment of Hexokinase. Methods: This study focused on the mammary adenocarcinoma cell line, MCF-7. Colony forming assays were used to analyze radiosensitization by CLT. Flow cytometry methods were used to analyze apoptotic vs necrotic fractions after treatment with CLT. Spectrophotometery was used to analyze the mitochondrial bound and soluble fraction of Hexokinase by means of relative enzymatic activity. Results: Our preliminary data have shown that CLT sensitizes MCF-7 cells to radiation in a dose and incubation time dependent manner up. We have also demonstrated that there are two radiosensitizing periods in MCF-7 cells with the first corresponding to the cycle arrest after 24 hours observed in other cell lines. The second radiosensitizing period occurs with incubation in CLT after irradiation which reaches maximum effect around 24 hours of incubation time. Preliminary data from our Hexokinase detachment assay show a factor of two increase in the ratio of unbound to bound Hexokinase when comparing incubation for 24 hours in media containing 0 and 20 µM CLT. Conclusion: This study and others indicate CLT as a possible radiosensitizing agent in cancer therapies. While CLT itself shows toxicity to the liver in high doses, this study further demonstrates that disruption of the Warburg Effect and unbinding of mitochondrial bound Hexokinase as a possible pathway for cancer treatment.

  3. Cell death induced by taxanes in breast cancer cells: cytochrome C is released in resistant but not in sensitive cells

    Czech Academy of Sciences Publication Activity Database

    Ehrlichová, Marie; Koc, Michal; Truksa, Jaroslav; Naďová, Zuzana; Václavíková, R.; Kovář, Jan

    2005-01-01

    Roč. 25, 6B (2005), s. 4215-4224 ISSN 0250-7005 R&D Projects: GA MZd(CZ) NL7567 Institutional research plan: CEZ:AV0Z50520514 Keywords : paclitaxel * cell death * breast cancer cells Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.604, year: 2005

  4. Silencing of poly(ADP-ribose) glycohydrolase sensitizes lung cancer cells to radiation through the abrogation of DNA damage checkpoint

    Energy Technology Data Exchange (ETDEWEB)

    Nakadate, Yusuke [Shien-Lab, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo 104-0045 (Japan); Department of Bioengineering, Graduate School of Engineering, Osaka City University, 3-3-138 Sugimoto, Sumiyoshi-ku, Osaka 558-8585 (Japan); Kodera, Yasuo; Kitamura, Yuka [Shien-Lab, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo 104-0045 (Japan); Tachibana, Taro [Department of Bioengineering, Graduate School of Engineering, Osaka City University, 3-3-138 Sugimoto, Sumiyoshi-ku, Osaka 558-8585 (Japan); Tamura, Tomohide [Division of Thoracic Oncology, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo 104-0045 (Japan); Koizumi, Fumiaki, E-mail: fkoizumi@ncc.go.jp [Division of Thoracic Oncology, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo 104-0045 (Japan)

    2013-11-29

    Highlights: •Radiosensitization by PARG silencing was observed in multiple lung cancer cells. •PAR accumulation was enhanced by PARG silencing after DNA damage. •Radiation-induced G2/M arrest and checkpoint activation were impaired by PARG siRNA. -- Abstract: Poly(ADP-ribose) glycohydrolase (PARG) is a major enzyme that plays a role in the degradation of poly(ADP-ribose) (PAR). PARG deficiency reportedly sensitizes cells to the effects of radiation. In lung cancer, however, it has not been fully elucidated. Here, we investigated whether PARG siRNA contributes to an increased radiosensitivity using 8 lung cancer cell lines. Among them, the silencing of PARG induced a radiosensitizing effect in 5 cell lines. Radiation-induced G2/M arrest was largely suppressed by PARG siRNA in PC-14 and A427 cells, which exhibited significantly enhanced radiosensitivity in response to PARG knockdown. On the other hand, a similar effect was not observed in H520 cells, which did not exhibit a radiosensitizing effect. Consistent with a cell cycle analysis, radiation-induced checkpoint signals were not well activated in the PC-14 and A427 cells when treated with PARG siRNA. These results suggest that the increased sensitivity to radiation induced by PARG knockdown occurs through the abrogation of radiation-induced G2/M arrest and checkpoint activation in lung cancer cells. Our findings indicate that PARG could be a potential target for lung cancer treatments when used in combination with radiotherapy.

  5. Metabolic Study of Cancer Cells Using a pH Sensitive Hydrogel Nanofiber Light Addressable Potentiometric Sensor.

    Science.gov (United States)

    Shaibani, Parmiss Mojir; Etayash, Hashem; Naicker, Selvaraj; Kaur, Kamaljit; Thundat, Thomas

    2017-01-27

    We report a simple, fast, and cost-effective approach that measures cancer cell metabolism and their response to anticancer drugs in real time. Using a Light Addressable Potentiometric Sensor integrated with pH sensitive hydrogel nanofibers (NF-LAPS), we detect localized changes in pH of the media as cancer cells consume glucose and release lactate. NF-LAPS shows a sensitivity response of 74 mV/pH for cancer cells. Cancer cells (MDA MB231) showed a response of ∼0.4 unit change in pH compared to virtually no change observed for normal cells (MCF10A). We also observed a drop in pH for the multidrug-resistant cancer cells (MDA-MB-435MDR) in the presence of doxorubicin. However, inhibition of the metabolic enzymes such as hexokinase and lactate dehydrogenase-A suggested an improvement in the efficacy of doxorubicin by decreasing the level of acidification. This approach, based on extracellular acidification, enhances our understanding of cancer cell metabolic modes and their response to chemotherapies, which will help in the development of better treatments, including choice of drugs and dosages.

  6. Low ATM protein expression and depletion of p53 correlates with olaparib sensitivity in gastric cancer cell lines

    Science.gov (United States)

    Kubota, Eiji; Williamson, Christopher T; Ye, Ruiqiong; Elegbede, Anifat; Peterson, Lars; Lees-Miller, Susan P; Bebb, D Gwyn

    2014-01-01

    Small-molecule inhibitors of poly (ADP-ribose) polymerase (PARP) have shown considerable promise in the treatment of homologous recombination (HR)-defective tumors, such as BRCA1- and BRCA2-deficient breast and ovarian cancers. We previously reported that mantle cell lymphoma cells with deficiency in ataxia telangiectasia mutated (ATM) are sensitive to PARP-1 inhibitors in vitro and in vivo. Here, we report that PARP inhibitors can potentially target ATM deficiency arising in a solid malignancy. We show that ATM protein expression varies between gastric cancer cell lines, with NUGC4 having significantly reduced protein levels. Significant correlation was found between ATM protein expression and sensitivity to the PARP inhibitor olaparib, with NUGC4 being the most sensitive. Moreover, reducing ATM kinase activity using a small-molecule inhibitor (KU55933) or shRNA-mediated depletion of ATM protein enhanced olaparib sensitivity in gastric cancer cell lines with depletion or inactivation of p53. Our results demonstrate that ATM is a potential predictive biomarker for PARP-1 inhibitor activity in gastric cancer harboring disruption of p53, and that combined inhibition of ATM and PARP-1 is a rational strategy for expanding the utility of PARP-1 inhibitors to gastric cancer with p53 disruption. PMID:24841718

  7. Suppression of progranulin expression inhibits bladder cancer growth and sensitizes cancer cells to cisplatin

    OpenAIRE

    Buraschi, Simone; Xu, Shi-Qiong; Stefanello, Manuela; Moskalev, Igor; Morcavallo, Alaide; Genua, Marco; Tanimoto, Ryuta; Birbe, Ruth; Peiper, Stephen C.; Gomella, Leonard G.; Belfiore, Antonino; Black, Peter C.; Iozzo, Renato V.; Morrione, Andrea

    2016-01-01

    We have recently demonstrated a critical role for progranulin in bladder cancer. Progranulin contributes, as an autocrine growth factor, to the transformed phenotype by modulating Akt-and MAPK-driven motility, invasion and anchorage-independent growth. Progranulin also induces F-actin remodeling by interacting with the F-actin binding protein drebrin. In addition, progranulin is overexpressed in invasive bladder cancer compared to normal tissue controls, suggesting that progranulin might play...

  8. A vertically aligned carbon nanotube-based impedance sensing biosensor for rapid and high sensitive detection of cancer cells.

    Science.gov (United States)

    Abdolahad, Mohammad; Taghinejad, Mohammad; Taghinejad, Hossein; Janmaleki, Mohsen; Mohajerzadeh, Shams

    2012-03-21

    A novel vertically aligned carbon nanotube based electrical cell impedance sensing biosensor (CNT-ECIS) was demonstrated for the first time as a more rapid, sensitive and specific device for the detection of cancer cells. This biosensor is based on the fast entrapment of cancer cells on vertically aligned carbon nanotube arrays and leads to mechanical and electrical interactions between CNT tips and entrapped cell membranes, changing the impedance of the biosensor. CNT-ECIS was fabricated through a photolithography process on Ni/SiO(2)/Si layers. Carbon nanotube arrays have been grown on 9 nm thick patterned Ni microelectrodes by DC-PECVD. SW48 colon cancer cells were passed over the surface of CNT covered electrodes to be specifically entrapped on elastic nanotube beams. CNT arrays act as both adhesive and conductive agents and impedance changes occurred as fast as 30 s (for whole entrapment and signaling processes). CNT-ECIS detected the cancer cells with the concentration as low as 4000 cells cm(-2) on its surface and a sensitivity of 1.7 × 10(-3)Ω cm(2). Time and cell efficiency factor (TEF and CEF) parameters were defined which describe the sensor's rapidness and resolution, respectively. TEF and CEF of CNT-ECIS were much higher than other cell based electrical biosensors which are compared in this paper.

  9. MicroRNA signature of cis-platin resistant vs. cis-platin sensitive ovarian cancer cell lines

    Directory of Open Access Journals (Sweden)

    Kumar Smriti

    2011-09-01

    Full Text Available Abstract Background Ovarian cancer is the leading cause of death from gynecologic cancer in women worldwide. According to the National Cancer Institute, ovarian cancer has the highest mortality rate among all the reproductive cancers in women. Advanced stage diagnosis and chemo/radio-resistance is a major obstacle in treating advanced ovarian cancer. The most commonly employed chemotherapeutic drug for ovarian cancer treatment is cis-platin. As with most chemotherapeutic drugs, many patients eventually become resistant to cis-platin and therefore, diminishing its effect. The efficacy of current treatments may be improved by increasing the sensitivity of cancer cells to chemo/radiation therapies. Methods The present study is focused on identifying the differential expression of regulatory microRNAs (miRNAs between cis-platin sensitive (A2780, and cis-platin resistant (A2780/CP70 cell lines. Cell proliferation assays were conducted to test the sensitivity of the two cell lines to cis-platin. Differential expression patterns of miRNA between cis-platin sensitive and cis-platin resistant cell lines were analyzed using novel LNA technology. Results Our results revealed changes in expression of 11 miRNAs out of 1,500 miRNAs analyzed. Out of the 11 miRNAs identified, 5 were up-regulated in the A2780/CP70 cell line and 6 were down regulated as compared to cis-platin sensitive A2780 cells. Our microRNA data was further validated by quantitative real-time PCR for these selected miRNAs. Ingenuity Pathway Analysis (IPA and Kyoto Encyclopedia of Genes and Genomes (KEGG analysis was performed for the selected miRNAs and their putative targets to identify the potential pathways and networks involved in cis-platin resistance. Conclusions Our data clearly showed the differential expression of 11 miRNAs in cis-platin resistant cells, which could potentially target many important pathways including MAPK, TGF-β signaling, actin cytoskeleton, ubiquitin mediated

  10. Knock-down of NDRG2 sensitizes cervical cancer Hela cells to cisplatin through suppressing Bcl-2 expression

    International Nuclear Information System (INIS)

    Liu, Junye; Guo, Guozhen; Yang, Le; Zhang, Jian; Zhang, Jing; Chen, Yongbin; Li, Kangchu; Li, Yurong; Li, Yan; Yao, Libo

    2012-01-01

    NDRG2, a member of N-Myc downstream regulated gene family, plays some roles in cellular stress, cell differentiation and tumor suppression. We have found that NDRG2 expression in cervical cancer Hela cells increases significantly upon stimulation with cisplatin, the most popular chemotherapeutic agent currently used for the treatment of advanced cervical cancer. This interesting phenomenon drove us to evaluate the role of NDRG2 in chemosensitivity of Hela cells. In the present study, RNA interference was employed to down-regulate NDRG2 expression in Hela cells. RT-PCR and Western blot were used to detect expression of NDRG2, Bcl-2 and Bax in cancer cells. Real-time PCR was applied to detect miR-15b and miR-16 expression levels. Drug sensitivity was determined with MTT assay. Cell cloning efficiency was evaluated by Colony-forming assay. Apoptotic cells were detected with annexin V staining and flow cytometry. In vitro drug sensitivity assay revealed that suppression of NDRG2 could sensitize Hela cells to cisplatin. Down-regulation of NDRG2 didn’t influence the colony-forming ability but promoted cisplatin-induced apoptosis of Hela cells. Inhibition of NDRG2 in Hela cells was accompanied by decreased Bcl-2 protein level. However, Bcl-2 mRNA level was not changed in Hela cells with down-regulation of NDRG2. Further study indicated that miR-15b and miR-16, two microRNAs targetting Bcl-2, were significantly up-regulated in NDRG2-suppressed Hela cells. These data suggested that down-regulation of NDRG2 could enhance sensitivity of Hela cells to cisplatin through inhibiting Bcl-2 protein expression, which might be mediated by up-regulating miR-15b and miR-16

  11. Identification of breast cancer cell subtypes sensitive to ATG4B inhibition

    OpenAIRE

    Bortnik, Svetlana; Choutka, Courtney; Horlings, Hugo M.; Leung, Samuel; Baker, Jennifer H.; Lebovitz, Chandra; Dragowska, Wieslawa H.; Go, Nancy E.; Bally, Marcel B.; Minchinton, Andrew I.; Gelmon, Karen A.; Gorski, Sharon M.

    2016-01-01

    Autophagy, a lysosome-mediated degradation and recycling process, functions in advanced malignancies to promote cancer cell survival and contribute to cancer progression and drug resistance. While various autophagy inhibition strategies are under investigation for cancer treatment, corresponding patient selection criteria for these autophagy inhibitors need to be developed. Due to its central roles in the autophagy process, the cysteine protease ATG4B is one of the autophagy proteins being pu...

  12. Starvation-induced activation of ATM/Chk2/p53 signaling sensitizes cancer cells to cisplatin

    Directory of Open Access Journals (Sweden)

    Shi Yandong

    2012-12-01

    Full Text Available Abstract Background Optimizing the safety and efficacy of standard chemotherapeutic agents such as cisplatin (CDDP is of clinical relevance. Serum starvation in vitro and short-term food starvation in vivo both stress cells by the sudden depletion of paracrine growth stimulation. Methods The effects of serum starvation on CDDP toxicity were investigated in normal and cancer cells by assessing proliferation, cell cycle distribution and activation of DNA-damage response and of AMPK, and were compared to effects observed in cells grown in serum-containing medium. The effects of short-term food starvation on CDDP chemotherapy were assessed in xenografts-bearing mice and were compared to effects on tumor growth and/or regression determined in mice with no diet alteration. Results We observed that serum starvation in vitro sensitizes cancer cells to CDDP while protecting normal cells. In detail, in normal cells, serum starvation resulted in a complete arrest of cellular proliferation, i.e. depletion of BrdU-incorporation during S-phase and accumulation of the cells in the G0/G1-phase of the cell cycle. Further analysis revealed that proliferation arrest in normal cells is due to p53/p21 activation, which is AMPK-dependent and ATM-independent. In cancer cells, serum starvation also decreased the fraction of S-phase cells but to a minor extent. In contrast to normal cells, serum starvation-induced p53 activation in cancer cells is both AMPK- and ATM-dependent. Combination of CDDP with serum starvation in vitro increased the activation of ATM/Chk2/p53 signaling pathway compared to either treatment alone resulting in an enhanced sensitization of cancer cells to CDDP. Finally, short-term food starvation dramatically increased the sensitivity of human tumor xenografts to cisplatin as indicated not only by a significant growth delay, but also by the induction of complete remission in 60% of the animals bearing mesothelioma xenografts, and in 40% of the

  13. Alpha2,3-sialyltransferase III knockdown sensitized ovarian cancer cells to cisplatin-induced apoptosis.

    Science.gov (United States)

    Wang, Xiaoyu; Zhang, Yiting; Lin, Haiyingjie; Liu, Yan; Tan, Yi; Lin, Jie; Gao, Fenze; Lin, Shaoqiang

    2017-01-22

    Emerging evidence indicates that β-galactoside-α2,3-sialyltransferase III (ST3Gal3) involves in development, inflammation, neoplastic transformation, and metastasis. However, the role of ST3Gal3 in regulating cancer chemoresistance remains elusive. Herein, we investigated the functional effects of ST3Gal3 in cisplatin-resistant ovarian cancer cells. We found that the levels of ST3Gal3 mRNA differed significantly among ovarian cancer cell lines. HO8910PM cells that have high invasive and metastatic capacity express elevated ST3Gal3 mRNA and are resistant to cisplatin, comparing to SKOV3 cells that have a lower level of ST3Gal3 expression and are more chemosensitive to cisplatin. We found that the expression of ST3Gal3 has reverse correlation with the dosage of cisplatin used in both SKOV3 and HO8910PM cells, and high dose of cisplatin could down-regulate ST3Gal3 expression. We then examined the functional effects of ST3Gal3 knockdown in cancer cell lines using FACS analysis. The number of apoptotic cells was much higher in cells if ST3Gal3 expression was knocked down by siRNA and/or by treating cells with higher dosage of cisplatin in comparison to control cells. Interestingly, in HO8910PM cells with ST3Gal3 knockdown, the levels of caspase 8 and caspase 3 proteins increased, which was more obvious in cells treated with both ST3Gal3 knockdown and cisplatin, suggesting that ST3Gal3 knockdown synergistically enhanced cisplatin-induced apoptosis in ovarian cancer cells. Taken together, these results uncover an alternative mechanism of cisplatin-resistance through ST3Gal3 and open a window for effective prevention of chemoresistance and relapse of ovarian cancer by targeting ST3Gal3. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Histone Deacetylase Inhibitor Induced Radiation Sensitization Effects on Human Cancer Cells after Photon and Hadron Radiation Exposure

    Directory of Open Access Journals (Sweden)

    Ariungerel Gerelchuluun

    2018-02-01

    Full Text Available Suberoylanilide hydroxamic acid (SAHA is a histone deacetylase inhibitor, which has been widely utilized throughout the cancer research field. SAHA-induced radiosensitization in normal human fibroblasts AG1522 and lung carcinoma cells A549 were evaluated with a combination of γ-rays, proton, and carbon ion exposure. Growth delay was observed in both cell lines during SAHA treatment; 2 μM SAHA treatment decreased clonogenicity and induced cell cycle block in G1 phase but 0.2 μM SAHA treatment did not show either of them. Low LET (Linear Energy Transfer irradiated A549 cells showed radiosensitization effects on cell killing in cycling and G1 phase with 0.2 or 2 μM SAHA pretreatment. In contrast, minimal sensitization was observed in normal human cells after low and high LET radiation exposure. The potentially lethal damage repair was not affected by SAHA treatment. SAHA treatment reduced the rate of γ-H2AX foci disappearance and suppressed RAD51 and RPA (Replication Protein A focus formation. Suppression of DNA double strand break repair by SAHA did not result in the differences of SAHA-induced radiosensitization between human cancer cells and normal cells. In conclusion, our results suggest SAHA treatment will sensitize cancer cells to low and high LET radiation with minimum effects to normal cells.

  15. The Urtica dioica extract enhances sensitivity of paclitaxel drug to MDA-MB-468 breast cancer cells.

    Science.gov (United States)

    Mohammadi, Ali; Mansoori, Behzad; Aghapour, Mahyar; Shirjang, Solmaz; Nami, Sanam; Baradaran, Behzad

    2016-10-01

    Due to the chemo resistant nature of cancer cells and adverse effects of current therapies, researchers are looking for the most efficient therapeutic approach which has the lowest side effects and the highest toxicity on cancer cells. The aim of the present study was to investigate the synergic effect of Urtica dioica extract in combination with paclitaxel on cell death and invasion of human breast cancer MDA-MB-468 cell line. To determine the cytotoxic effects of Urtica dioica extract with paclitaxel, MTT assay was performed. The scratch test was exploited to assess the effects of Urtica dioica, Paclitaxel alone and combination on migration of cancer cells. The expression levels of snail-1, ZEB1, ZEB2, twist, Cdc2, cyclin B1 and Wee1 genes were quantified using qRT-PCR and western blot performed for snail-1expression. The effects of plant extract, Paclitaxel alone and combination on different phases of cell cycle was analyzed using flow cytometry. Results of MTT assay showed that Urtica dioica significantly destroyed cancer cells. Interestingly, Concurrent use of Urtica dioica extract with paclitaxel resulted in decreased IC50 dose of paclitaxel. Moreover, findings of scratch assay exhibited the inhibitory effects of Urtica dioica, Paclitaxel alone and combination on migration of MDA-MB-468 cell line. Our findings also demonstrated that the extract substantially decreased the Snail-1 and related gene expression. Ultimately, Cell cycle arrest occurred at G2/M phase post-treatment by deregulating Cdc2 and wee1. Our results demonstrated that the dichloromethane extract of Urtica dioica inhibit cell growth and migration. Also, Urtica dioica extract substantially increased sensitivity of breast cancer cells to paclitaxel. Therefore, it can be used as a potential candidate for treatment of breast cancer with paclitaxel. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  16. 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.

  17. Fluorescent CSC models evidence that targeted nanomedicines improve treatment sensitivity of breast and colon cancer stem cells.

    Science.gov (United States)

    Gener, Petra; Gouveia, Luis Pleno; Sabat, Guillem Romero; de Sousa Rafael, Diana Fernandes; Fort, Núria Bergadà; Arranja, Alexandra; Fernández, Yolanda; Prieto, Rafael Miñana; Ortega, Joan Sayos; Arango, Diego; Abasolo, Ibane; Videira, Mafalda; Schwartz, Simo

    2015-11-01

    To be able to study the efficacy of targeted nanomedicines in marginal population of highly aggressive cancer stem cells (CSC), we have developed a novel in vitro fluorescent CSC model that allows us to visualize these cells in heterogeneous population and to monitor CSC biological performance after therapy. In this model tdTomato reporter gene is driven by CSC specific (ALDH1A1) promoter and contrary to other similar models, CSC differentiation and un-differentiation processes are not restrained and longitudinal studies are feasible. We used this model for preclinical validation of poly[(d,l-lactide-co-glycolide)-co-PEG] (PLGA-co-PEG) micelles loaded with paclitaxel. Further, active targeting against CD44 and EGFR receptors was validated in breast and colon cancer cell lines. Accordingly, specific active targeting toward surface receptors enhances the performance of nanomedicines and sensitizes CSC to paclitaxel based chemotherapy. Many current cancer therapies fail because of the failure to target cancer stem cells. This surviving population soon proliferates and differentiates into more cancer cells. In this interesting article, the authors designed an in vitro cancer stem cell model to study the effects of active targeting using antibody-labeled micelles containing chemotherapeutic agent. This new model should allow future testing of various drug/carrier platforms before the clinical phase. Copyright © 2015 Elsevier Inc. All rights reserved.

  18. Co-stimulatory signaling determines tumor antigen sensitivity and persistence of CAR T cells targeting PSCA+ metastatic prostate cancer.

    Science.gov (United States)

    Priceman, Saul J; Gerdts, Ethan A; Tilakawardane, Dileshni; Kennewick, Kelly T; Murad, John P; Park, Anthony K; Jeang, Brook; Yamaguchi, Yukiko; Yang, Xin; Urak, Ryan; Weng, Lihong; Chang, Wen-Chung; Wright, Sarah; Pal, Sumanta; Reiter, Robert E; Wu, Anna M; Brown, Christine E; Forman, Stephen J

    2018-01-01

    Advancing chimeric antigen receptor (CAR)-engineered adoptive T cells for the treatment of solid cancers is a major focus in the field of immunotherapy, given impressive recent clinical responses in hematological malignancies. Prostate cancer may be amenable to T cell-based immunotherapy since several tumor antigens, including prostate stem-cell antigen (PSCA), are widely over-expressed in metastatic disease. While antigen selectivity of CARs for solid cancers is crucial, it is problematic due to the absence of truly restricted tumor antigen expression and potential safety concerns with "on-target off-tumor" activity. Here, we show that the intracellular co-stimulatory signaling domain can determine a CAR's sensitivity for tumor antigen expression. A 4-1BB intracellular co-stimulatory signaling domain in PSCA-CARs confers improved selectivity for higher tumor antigen density, reduced T cell exhaustion phenotype, and equivalent tumor killing ability compared to PSCA-CARs containing the CD28 co-stimulatory signaling domain. PSCA-CARs exhibit robust in vivo anti-tumor activity in patient-derived bone-metastatic prostate cancer xenograft models, and 4-1BB-containing CARs show superior T cell persistence and control of disease compared with CD28-containing CARs. Our study demonstrates the importance of co-stimulation in defining an optimal CAR T cell, and also highlights the significance of clinically relevant models in developing solid cancer CAR T cell therapies.

  19. Co-stimulatory signaling determines tumor antigen sensitivity and persistence of CAR T cells targeting PSCA+ metastatic prostate cancer

    Science.gov (United States)

    Priceman, Saul J.; Gerdts, Ethan A.; Tilakawardane, Dileshni; Kennewick, Kelly T.; Murad, John P.; Park, Anthony K.; Jeang, Brook; Yamaguchi, Yukiko; Urak, Ryan; Weng, Lihong; Chang, Wen-Chung; Wright, Sarah; Pal, Sumanta; Reiter, Robert E.; Brown, Christine E.; Forman, Stephen J.

    2018-01-01

    ABSTRACT Advancing chimeric antigen receptor (CAR)-engineered adoptive T cells for the treatment of solid cancers is a major focus in the field of immunotherapy, given impressive recent clinical responses in hematological malignancies. Prostate cancer may be amenable to T cell-based immunotherapy since several tumor antigens, including prostate stem-cell antigen (PSCA), are widely over-expressed in metastatic disease. While antigen selectivity of CARs for solid cancers is crucial, it is problematic due to the absence of truly restricted tumor antigen expression and potential safety concerns with “on-target off-tumor” activity. Here, we show that the intracellular co-stimulatory signaling domain can determine a CAR's sensitivity for tumor antigen expression. A 4-1BB intracellular co-stimulatory signaling domain in PSCA-CARs confers improved selectivity for higher tumor antigen density, reduced T cell exhaustion phenotype, and equivalent tumor killing ability compared to PSCA-CARs containing the CD28 co-stimulatory signaling domain. PSCA-CARs exhibit robust in vivo anti-tumor activity in patient-derived bone-metastatic prostate cancer xenograft models, and 4-1BB-containing CARs show superior T cell persistence and control of disease compared with CD28-containing CARs. Our study demonstrates the importance of co-stimulation in defining an optimal CAR T cell, and also highlights the significance of clinically relevant models in developing solid cancer CAR T cell therapies. PMID:29308300

  20. 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...

  1. 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

    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 for...

  2. Specific sensitivity of small cell lung cancer cell lines to the snake venom toxin taipoxin

    DEFF Research Database (Denmark)

    Poulsen, Thomas T; Pedersen, Nina; Perin, Mark S

    2005-01-01

    and relatively specifically expressed in SCLC, consistent with the neuroendocrine features of this cancer. Normally, NPR is exclusively expressed in neurons, where it associates with the homologous proteins neuronal pentraxins 1 and 2 (NP1 and NP2) in complexes capable of binding the snake venom neurotoxin...

  3. MUS81 is associated with cell proliferation and cisplatin sensitivity in serous ovarian cancer

    Energy Technology Data Exchange (ETDEWEB)

    Xie, Suhong; Zheng, Hui [Department of Clinical Laboratory, Fudan University Shanghai Cancer Center, Shanghai (China); Department of Oncology, Shanghai Medical College, Fudan University, Shanghai (China); Wen, Xuemei [Department of Oncology, Shanghai Medical College, Fudan University, Shanghai (China); Sun, Jiajun; Wang, Yanchun; Gao, Xiang; Guo, Lin [Department of Clinical Laboratory, Fudan University Shanghai Cancer Center, Shanghai (China); Department of Oncology, Shanghai Medical College, Fudan University, Shanghai (China); Lu, Renquan, E-mail: lurenquan@126.com [Department of Clinical Laboratory, Fudan University Shanghai Cancer Center, Shanghai (China); Department of Oncology, Shanghai Medical College, Fudan University, Shanghai (China)

    2016-08-05

    The dysfunction of DNA damage repair (DDR) pathway contributes to tumorigenesis and drug-resistance in cancer. MUS81 is a member of the conserved xeroderma pigmentosum group F (XPF) family protein of endonucleases, which is important to the DDR pathway. However, the role of MUS81 in the development of ovarian cancer remains uncertain. To explore the expression of MUS81 and its association to serous ovarian cancer (SOC), 43 biopsies of SOC patients were detected by qRT-PCR, and 29 specimens were further performed by immunohistochemistry analysis. Here, we observed that MUS81 was over-expressed in SOC tissues at both transcript and protein levels, and the expression level of MUS81 protein in ovarian cancer cell lines was also higher than that in human normal ovarian surface epithelial cell line (HOSEpiC). We also found that down-regulation of MUS81 expression in ovarian cancer cells inhibited cell proliferation and colony formation ability, and influenced cell cycle progression. Moreover, inhibition of MUS81 expression induced cellular senescence and enhanced the antitumor effect of cisplatin. Down-regulation of MUS81 expression could suppress the growth and development of SOC. These results indicate that MUS81 might play important roles in the progression of SOC and influence the antitumor effect of cisplatin. - Highlights: • MUS81 was overexpression in serous ovarian cancer (SOC). • Meanwhile down-regulation of inhibited cell proliferation and influenced cell cycle progression. • Inhibition of MUS81 induced cell cellular senescence and enhanced the antitumor effect of cisplatin. • Down-regulation of MUS81 expression could suppress the growth and development of SOC.

  4. MUS81 is associated with cell proliferation and cisplatin sensitivity in serous ovarian cancer

    International Nuclear Information System (INIS)

    Xie, Suhong; Zheng, Hui; Wen, Xuemei; Sun, Jiajun; Wang, Yanchun; Gao, Xiang; Guo, Lin; Lu, Renquan

    2016-01-01

    The dysfunction of DNA damage repair (DDR) pathway contributes to tumorigenesis and drug-resistance in cancer. MUS81 is a member of the conserved xeroderma pigmentosum group F (XPF) family protein of endonucleases, which is important to the DDR pathway. However, the role of MUS81 in the development of ovarian cancer remains uncertain. To explore the expression of MUS81 and its association to serous ovarian cancer (SOC), 43 biopsies of SOC patients were detected by qRT-PCR, and 29 specimens were further performed by immunohistochemistry analysis. Here, we observed that MUS81 was over-expressed in SOC tissues at both transcript and protein levels, and the expression level of MUS81 protein in ovarian cancer cell lines was also higher than that in human normal ovarian surface epithelial cell line (HOSEpiC). We also found that down-regulation of MUS81 expression in ovarian cancer cells inhibited cell proliferation and colony formation ability, and influenced cell cycle progression. Moreover, inhibition of MUS81 expression induced cellular senescence and enhanced the antitumor effect of cisplatin. Down-regulation of MUS81 expression could suppress the growth and development of SOC. These results indicate that MUS81 might play important roles in the progression of SOC and influence the antitumor effect of cisplatin. - Highlights: • MUS81 was overexpression in serous ovarian cancer (SOC). • Meanwhile down-regulation of inhibited cell proliferation and influenced cell cycle progression. • Inhibition of MUS81 induced cell cellular senescence and enhanced the antitumor effect of cisplatin. • Down-regulation of MUS81 expression could suppress the growth and development of SOC.

  5. Effects of Smac gene over-expression on radiotherapeutic sensitivity of cervical cancer cell line HeLa

    International Nuclear Information System (INIS)

    Zheng Liduan; Wang Liang; Tong Qiangsong; Fei Shihong; Xiong Yufang; Wu Gang

    2005-01-01

    Objective: To study the effects of extrinsic Smac gene transfection and its over-expression on radiotherapeutic sensitivity of cervical cancer cells, in order to explore a novel strategy for ameliorating radiotherapy of cervical cancer. Methods: After Smac gene was transferred into cells of cervical cancer cell line HeLa, the subclone cells were obtained by persistent G 418 selection. Cellular Smac gene expression was determined by RT-PCR and Western blot. After treatment with X-ray irradiation, cellular growth activity in vitro was investigated by MTT colorimetry. Cellular apoptosis and its rate were determined by electron microscopy, Annexin V-FITC and propidium iodide staining flow cytometry. Cellular Caspase-3 protein expression and its activity were assayed by Western blot and colorimetry. Results: RT-PCR and Western blot demonstrated that Smac mRNA and protein levels of HeLa/Smac cells, the selected subclone cells of cervical cancer cell line, were significantly higher than those of HeLa cells (P<0.01). After treated with 8 Gy X-ray irradiation, growth activity of HeLa/Smac cells reduced by 10.19%(P<0.01), as compared with that of HeLa cells. Partial HeLa/Smac cancer cells presented characteristic morphological changes of apoptosis under electron microscope, with an apoptosis rate of 16.4%, which was significantly higher than that of HeLa cells(6.2%, P<0.01). Compared with HeLa cells, Caspase-3 expression level in HeLa/Smac was improved significantly (P<0.01), while its activity was 3.42 times as much as that of HeLa cells (P<0.01). Conclusion: Stable transfection of extrinsic Smac gene and its over-expression in cervical cancer cell line could significantly enhance cellular caspase-3 expression and activity, ameliorate apoptosis-inducing effects of radiation on cancer cells, which would be a novel strategy to improve radiotherapeutic effects for cervical cancer. (authors)

  6. Radiation induced bystander effects in modification of cellular radio-sensitivity in human cancer cells

    International Nuclear Information System (INIS)

    Pandey, B.N.

    2012-01-01

    Radiation-induced Bystander Effect is manifestation of radiation effects in non-irradiated cells in the population. The phenomenon may have significant implication in risk of radiation induced cancer incidence and outcome of cancer radiotherapy. To understand the bystander interaction in tumor cells, we have studied secretion of diffusible factors from control and irradiated tumor cells of different origin. Our results showed a good correlation between magnitude of secretion of diffusible factors and survival of tumor cells. These diffusible factors are shown to affect proliferation and survival of tumor cells involving regulation of kinases and genes/proteins involved in apoptotic machinery. Our experiments using pharmacological inhibitors showed involvement of activating transcription factor 2 (ATF-2) signaling in survival of tumor cells after treatment with diffusible factors. These factors seem to be involved in exerting radio-resistance in tumor cells. Furthermore, in proton microbeam irradiation studies showed induction of double strand break measured as gH2AX foci in human lung carcinoma cells, which was found to propagate to bystander tumor cells during post-irradiation incubation. Implication of these observations in outcome of cancer radiotherapy scenario would be discussed. (author)

  7. 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.

  8. HPW-RX40 restores anoikis sensitivity of human breast cancer cells by inhibiting integrin/FAK signaling

    Energy Technology Data Exchange (ETDEWEB)

    Chen, I-Hua; Shih, Hsin-Chu [Graduate Institute of Natural Products, Kaohsiung Medical University, Kaohsiung, Taiwan (China); Hsieh, Pei-Wen [Graduate Institute of Natural Products, School of Traditional Chinese Medicine, and Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan, Taiwan (China); Chang, Fang-Rong [Graduate Institute of Natural Products, Kaohsiung Medical University, Kaohsiung, Taiwan (China); Cancer Center, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan (China); Wu, Yang-Chang, E-mail: yachwu@mail.cmu.edu [School of Pharmacy, College of Pharmacy, China Medical University, Taichung, Taiwan (China); Wu, Chin-Chung, E-mail: ccwu@kmu.edu.tw [Graduate Institute of Natural Products, Kaohsiung Medical University, Kaohsiung, Taiwan (China); Department of Marine Biotechnology and Resources, National Sun Yat-sen University, Kaohsiung 80708, Taiwan (China); Research Center for Natural Products and Drug Development, Kaohsiung Medical University, Kaohsiung, Taiwan (China)

    2015-12-01

    Anoikis is defined as apoptosis, which is induced by inappropriate cell–matrix interactions. Cancer cells with anoikis resistance tend to undergo metastasis, and this phenomenon has been reported to be associated with integrin and FAK activity. HPW-RX40 is a derivative of 3,4-methylenedioxy-β-nitrostyrene, which is known to prevent platelet aggregation by inhibition of integrin. In the present study, we investigated the effect of HPW-RX40 on an anoikis-resistant human breast cancer cell line MDA-MB-231. HPW-RX40 inhibited cell aggregation and induced cell death in suspending MDA-MB-231 cells, but had only little effect on the monolayer growth of adherent cells. Analysis of caspase activation and poly (ADP-ribose) polymerase (PARP) cleavage confirmed anoikis in HPW-RX40-treated suspending cancer cells. HPW-RX40 also affected the Bcl-2 family proteins in detached cancer cells. Furthermore, HPW-RX40 inhibited detachment-induced activation of FAK and the downstream phosphorylation of Src and paxillin, but did not affect this pathway in adherent cancer cells. We also found that the expression and activation of β1 integrin in MDA-MB-231 cells were reduced by HPW-RX40. The combination of HPW-RX40 with an EGFR inhibitor led to enhanced anoikis and inhibition of the FAK pathway in breast cancer cells. Taken together, our results suggest that HPW-RX40 restores the anoikis sensitivity in the metastatic breast cancer cells by inhibiting integrin and subsequent FAK activation, and reveal a potential strategy for prevention of tumor metastasis. - Highlights: • The β-nitrostyrene derivative, HPW-RX40, induces anoikis in human breast cancer cells. • HPW-RX40 inhibits the integrin/FAK signaling pathway. • The combination of HPW-RX40 with an EGFR inhibitor leads to enhanced anoikis. • HPW-RX40 may have a potential to prevent the spread of metastatic breast cancer.

  9. HPW-RX40 restores anoikis sensitivity of human breast cancer cells by inhibiting integrin/FAK signaling

    International Nuclear Information System (INIS)

    Chen, I-Hua; Shih, Hsin-Chu; Hsieh, Pei-Wen; Chang, Fang-Rong; Wu, Yang-Chang; Wu, Chin-Chung

    2015-01-01

    Anoikis is defined as apoptosis, which is induced by inappropriate cell–matrix interactions. Cancer cells with anoikis resistance tend to undergo metastasis, and this phenomenon has been reported to be associated with integrin and FAK activity. HPW-RX40 is a derivative of 3,4-methylenedioxy-β-nitrostyrene, which is known to prevent platelet aggregation by inhibition of integrin. In the present study, we investigated the effect of HPW-RX40 on an anoikis-resistant human breast cancer cell line MDA-MB-231. HPW-RX40 inhibited cell aggregation and induced cell death in suspending MDA-MB-231 cells, but had only little effect on the monolayer growth of adherent cells. Analysis of caspase activation and poly (ADP-ribose) polymerase (PARP) cleavage confirmed anoikis in HPW-RX40-treated suspending cancer cells. HPW-RX40 also affected the Bcl-2 family proteins in detached cancer cells. Furthermore, HPW-RX40 inhibited detachment-induced activation of FAK and the downstream phosphorylation of Src and paxillin, but did not affect this pathway in adherent cancer cells. We also found that the expression and activation of β1 integrin in MDA-MB-231 cells were reduced by HPW-RX40. The combination of HPW-RX40 with an EGFR inhibitor led to enhanced anoikis and inhibition of the FAK pathway in breast cancer cells. Taken together, our results suggest that HPW-RX40 restores the anoikis sensitivity in the metastatic breast cancer cells by inhibiting integrin and subsequent FAK activation, and reveal a potential strategy for prevention of tumor metastasis. - Highlights: • The β-nitrostyrene derivative, HPW-RX40, induces anoikis in human breast cancer cells. • HPW-RX40 inhibits the integrin/FAK signaling pathway. • The combination of HPW-RX40 with an EGFR inhibitor leads to enhanced anoikis. • HPW-RX40 may have a potential to prevent the spread of metastatic breast cancer.

  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

    2010-10-01

    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. 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. Copyright © 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  12. Knockdown of BAG3 sensitizes bladder cancer cells to treatment with the BH3 mimetic ABT-737.

    Science.gov (United States)

    Mani, Jens; Antonietti, Patrick; Rakel, Stefanie; Blaheta, Roman; Bartsch, Georg; Haferkamp, Axel; Kögel, Donat

    2016-02-01

    BAG3 is overexpressed in several malignancies and mediates a non-canonical, selective form of (macro)autophagy. By stabilizing pro-survival Bcl-2 proteins in complex with HSP70, BAG3 can also exert an apoptosis-antagonizing function. ABT-737 is a high affinity Bcl-2 inhibitor that fails to target Mcl-1. This failure may confer resistance in various cancers. Urothelial cancer cells were treated with the BH3 mimetics ABT-737 and (-)-gossypol, a pan-Bcl-2 inhibitor which inhibits also Mcl-1. To clarify the importance of the core autophagy regulator ATG5 and BAG3 in ABT-737 treatment, cell lines carrying a stable lentiviral knockdown of ATG5 and BAG3 were created. The synergistic effect of ABT-737 and pharmaceutical inhibition of BAG3 with the HSF1 inhibitor KRIBB11 or sorafenib was also evaluated. Total cell death and apoptosis were quantified by FACS analysis of propidium iodide, annexin. Target protein analysis was conducted by Western blotting. Knockdown of BAG3 significantly downregulated Mcl-1 protein levels and sensitized urothelial cancer cells to apoptotic cell death induced by ABT-737, while inhibition of bulk autophagy through depletion of ATG5 had no discernible effect on cell death. Similar to knockdown of BAG3, pharmacological targeting of the BAG3/Mcl-1 pathway with KRIBB11 was capable to sensitize both cell lines to treatment with ABT-737. Our results show that BAG3, but not bulk autophagy has a major role in the response of bladder cancer cells to BH3 mimetics. They also suggest that BAG3 is a suitable target for combined therapies aimed at synergistically inducing apoptosis in bladder cancer.

  13. Silencing of BAG3 promotes the sensitivity of ovarian cancer cells to cisplatin via inhibition of autophagy.

    Science.gov (United States)

    Qiu, Shuang; Sun, Liang; Jin, Ye; An, Qi; Weng, Changjiang; Zheng, Jianhua

    2017-07-01

    Ovarian cancer is the most lethal disease among all gynecological malignancies. Interval cytoreductive surgery and cisplatin‑based chemotherapy are the recommended therapeutic strategies. However, acquired resistance to cisplatin remains a big challenge for the overall survival and prognosis in ovarian cancer. Complicated molecular mechanisms are involved in the process. At present, increasing evidence indicates that autophagy plays an important role in the prosurvival and resistance against chemotherapy. In the present study, as a novel autophagy regulator, BCL2‑associated athanogene 3 (BAG3) was investigated to study its role in cisplatin sensitivity in epithelial ovarian cancer. However, whether BAG3 participates in cisplatin sensitivity by inducing autophagy and the underlying mechanism in ovarian cancer cells remain to be clarified. Through the use of quantitative real-time PCR, western blot analysis, CCK-8 and immunofluorescence assays our data revealed that cisplatin-induced autophagy protected ovarian cancer cells from the toxicity of the drug and that this process was regulated by BAG3. Silencing of BAG3 increased cisplatin-induced apoptosis. The results also revealed BAG3 as a potential therapeutic target which enhanced the efficacy of cisplatin in ovarian cancer.

  14. 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...... 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...

  15. Mass spectrometry-based metabolic profiling of gemcitabine-sensitive and gemcitabine-resistant pancreatic cancer cells.

    Science.gov (United States)

    Fujimura, Yoshinori; Ikenaga, Naoki; Ohuchida, Kenoki; Setoyama, Daiki; Irie, Miho; Miura, Daisuke; Wariishi, Hiroyuki; Murata, Masaharu; Mizumoto, Kazuhiro; Hashizume, Makoto; Tanaka, Masao

    2014-03-01

    Gemcitabine resistance (GR) is one of the critical issues for therapy for pancreatic cancer, but the mechanism still remains unclear. Our aim was to increase the understanding of GR by metabolic profiling approach. To establish GR cells, 2 human pancreatic cancer cell lines, SUIT-2 and CAPAN-1, were exposed to increasing concentration of gemcitabine. Both parental and chemoresistant cells obtained by this treatment were subjected to metabolic profiling based on liquid chromatography-mass spectrometry. Multivariate statistical analyses, both principal component analysis and orthogonal partial least squares discriminant analysis, distinguished metabolic signature of responsiveness and resistance to gemcitabine in both SUIT-2 and CAPAN-1 cells. Among significantly different (P metabolic pathways such as amino acid, nucleotide, energy, cofactor, and vitamin pathways. Decreases in glutamine and proline levels as well as increases in aspartate, hydroxyproline, creatine, and creatinine levels were observed in chemoresistant cells from both cell lines. These results suggest that metabolic profiling can isolate distinct features of pancreatic cancer in the metabolome of gemcitabine-sensitive and GR cells. These findings may contribute to the biomarker discovery and an enhanced understanding of GR in pancreatic cancer.

  16. Palmitate-induced ER stress increases trastuzumab sensitivity in HER2/neu-positive breast cancer cells

    International Nuclear Information System (INIS)

    Baumann, Jan; Wong, Jason; Sun, Yan; Conklin, Douglas S.

    2016-01-01

    CHOP-dependent apoptosis as well as a partial activation of the ER stress response network via XBP1 and ATF6. This response appears to be a general feature of HER2/neu-positive breast cancer cells but not cells that overexpress only HER2/neu. Exogenous palmitate reduces HER2 and HER3 protein levels without changes in phosphorylation and sensitizes HER2/neu-positive breast cancer cells to treatment with the HER2-targeted therapy trastuzumab. Several studies have shown that HER2, FASN and fatty acid synthesis are functionally linked. Exogenous palmitate exerts its toxic effects in part through inducing ER stress, reducing HER2 expression and thereby sensitizing cells to trastuzumab. These data provide further evidence that HER2 signaling and fatty acid metabolism are highly integrated processes that may be important for disease development and progression. The online version of this article (doi:10.1186/s12885-016-2611-8) contains supplementary material, which is available to authorized users

  17. 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.

  18. A novel resveratrol-salinomycin combination sensitizes ER-positive breast cancer cells to apoptosis.

    Science.gov (United States)

    Venkatadri, Rajkumar; Iyer, Anand Krishnan V; Kaushik, Vivek; Azad, Neelam

    2017-08-01

    Resveratrol is a dietary compound that has been widely reported for its anticancer activities. However, successful extrapolation of its effects to pre-clinical studies is met with limited success due to inadequate bioavailability. We investigated the potential of combination therapy to improve the efficacy of resveratrol in a more physiologically relevant dose range. The effect of resveratrol on canonical Wnt signaling was evaluated by Western blotting. Wnt modulators HLY78 (activator) and salinomycin (inhibitor) were evaluated in combination with resveratrol for their effect on breast cancer cell viability (MTT assay), cell cycle progression and apoptosis (Western blotting). Bliss independency model was used to evaluate combinatorial effects of resveratrol-salinomycin combination. Resveratrol downregulated canonical Wnt signaling proteins in treated breast cancer cells (MCF-7, MDA-MB-231 and MDA-MB-468) in the dose range of 50-200μM, which also affected cellular viability. However, at very low doses (0-50μM), resveratrol exhibited no cellular toxicity. Co-treatment with salinomycin significantly potentiated the anti-cancer effects of resveratrol, whereas HLY78 co-treatment had minimal effect. Bliss independency model revealed that Wnt inhibition synergistically potentiates the effects of resveratrol in MCF-7 and BT474 cells. Significantly downregulated canonical Wnt signaling proteins and marker of epithelial-mesenchymal transition (EMT), vimentin were observed in cells treated with resveratrol-salinomycin combination. Cell cycle arrest, caspase activation and apoptosis induction in cells treated with resveratrol-salinomycin combination further confirmed the efficacy of the combination. We report a novel resveratrol-salinomycin combination for targeting ER-positive breast cancer cells and present evidence for successful pre-clinical implementation of resveratrol. Copyright © 2017 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban

  19. Differentially expressed proteins in human breat cancer cells sensitive andresistant to paclitaxel

    Czech Academy of Sciences Publication Activity Database

    Pavlíková, N.; Bartoňová, I.; Dinčáková, L.; Halada, Petr; Kovář, J.

    2014-01-01

    Roč. 45, č. 2 (2014), s. 822-830 ISSN 1019-6439 R&D Projects: GA MZd NT13679 Institutional support: RVO:61388971 Keywords : paclitaxel * cancer * breaast cells * expressed proteins * cytokeratin 18 Subject RIV: EC - Immunology Impact factor: 3.025, year: 2014

  20. Ganoderma lucidum exerts anti-tumor effects on ovarian cancer cells and enhances their sensitivity to cisplatin.

    Science.gov (United States)

    Zhao, Sufen; Ye, Gang; Fu, Guodong; Cheng, Jian-Xin; Yang, Burton B; Peng, Chun

    2011-05-01

    Ganoderma lucidum is a herbal mushroom known to have many health benefits, including the inhibition of tumor cell growth. However, the effect of Ganoderma lucidum on epithelial ovarian cancer (EOC), the most fatal gynecological malignancy, has not yet been reported. In this study, we determined whether Ganoderma lucidum regulates EOC cell activity. Using several cell lines derived from EOC, we found that Ganoderma lucidum strongly decreased cell numbers in a dose-dependent manner. Ganoderma lucidum also inhibited colony formation, cell migration and spheroid formation. In particular, Ganoderma lucidum was effective in inhibiting cell growth in both chemosensitive and chemoresistant cells and the treatment with Ganoderma lucidum significantly enhanced the effect of cisplatin on EOC cells. Furthermore, Ganoderma lucidum induced cell cycle arrest at the G2/M phase and also induced apoptosis by activating caspase 3. Finally, Ganoderma lucidum increased p53 but inhibited Akt expression. Taken together, these findings suggest that Ganoderma lucidum exerts multiple anti-tumor effects on ovarian cancer cells and can enhance the sensitivity of EOC cells to cisplatin.

  1. pH-sensitive intracellular photoluminescence of carbon nanotube-fluorescein conjugates in human ovarian cancer cells

    International Nuclear Information System (INIS)

    Chen, M T; Ishikawa, F N; Gundersen, M A; Gomez, L M; Vernier, P T; Zhou, C

    2009-01-01

    To add to the understanding of the properties of functionalized carbon nanotubes in biological applications, we report a monotonic pH sensitivity of the intracellular fluorescence emission of single-walled carbon nanotube-fluorescein carbazide (SWCNT-FC) conjugates in human ovarian cancer cells. Light-stimulated intracellular hydrolysis of the amide linkage and localized intracellular pH changes are proposed as mechanisms. SWCNT-FC conjugates may serve as intracellular pH sensors.

  2. γ-Aminobutyric acid inhibits the proliferation and increases oxaliplatin sensitivity in human colon cancer cells.

    Science.gov (United States)

    Song, Lihua; Du, Aiying; Xiong, Ying; Jiang, Jing; Zhang, Yao; Tian, Zhaofeng; Yan, Hongli

    2016-11-01

    γ-Aminobutyric acid (GABA) is a natural non-protein amino acid, which broadly exists in many plant parts and is widely used as an ingredient in the food industry. In mammals, it is widely distributed in central nervous system and non-neural tissues. In addition to a primary inhibitory neurotransmitter in the central nervous system, endogenous GABA content has been found to be elevated in neoplastic tissues in colon cancer. However, the effect of extraneous GABA on colon cancer has rarely been reported. In this study, we found the inhibitory effects of GABA on the proliferation of colon cancer cells (CCCs). The amino acid also suppressed metastasis of SW480 and SW620 cells. To further study the correlated mechanism, we analyzed the changes in cell cycle distribution and found that GABA suppressed cell cycle progression through G2/M or G1/S phase. Furthermore, RNA sequencing analysis revealed GABA-induced changes in the mRNA expression of 30 genes, including EGR1, MAPK4, NR4A1, Fos, and FosB, in all the three types of CCC. Importantly, GABA enhanced the anti-tumor efficacy of oxaliplatin (OXA) in subcutaneous xenograft tumor model in nude mice. The data suggest that GABA inhibits colon cancer cell proliferation perhaps by attenuating EGR1-NR4A1 axis, EGR1-Fos axis, and by disrupting MEK-EGR1 signaling pathway. This work reveals the pharmacological value of GABA derived from food and suggests that exogenous GABA might play an auxiliary role in polychemotherapy of colon cancer.

  3. 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. Copyright © 2015. Published by Elsevier B.V.

  4. Critical roles of mucin-1 in sensitivity of lung cancer cells to tumor necrosis factor-alpha and dexamethasone.

    Science.gov (United States)

    Xu, Menglin; Wang, Xiangdong

    2017-08-01

    Lung cancer is the leading cause of death from cancer. Mucins are glycoproteins with high molecular weight, responsible for cell growth, differentiation, and signaling, and were proposed to be correlated with gene heterogeneity of lung cancer. Here, we report aberrant expression of mucin genes and tumor necrosis factor receptors in lung adenocarcinoma tissues compared with normal tissues in GEO datasets. Mucin-1 (MUC1) gene was selected and considered as the target gene; furthermore, the expression pattern of adenocarcinomic cells (A549, H1650, or H1299 cells) was validated under the stimulation with tumor necrosis factor-alpha (TNFα) or dexamethasone (DEX), separately. MUC1 gene interference was done to A549 cells to show its role in sensitivity of lung cancer cells to TNFα and DEX. Results of our experiments indicate that MUC1 may regulate the influence of inflammatory mediators in effects of glucocorticoids (GCs), as a regulatory target to improve therapeutics. It shows the potential effect of MUC1 and GCs in lung adenocarcinoma (LADC), which may help in LADC treatment in the future.

  5. Bone stroma-derived cells change coregulators recruitment to androgen receptor and decrease cell proliferation in androgen-sensitive and castration-resistant prostate cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Villagran, Marcelo A.; Gutierrez-Castro, Francisco A.; Pantoja, Diego F.; Alarcon, Jose C.; Fariña, Macarena A.; Amigo, Romina F.; Muñoz-Godoy, Natalia A. [Molecular Endocrinology and Oncology Laboratory, University of Concepcion, Concepcion (Chile); Pinilla, Mabel G. [Department of Medical Specialties, School of Medicine, University of Concepcion, Concepcion (Chile); Peña, Eduardo A.; Gonzalez-Chavarria, Ivan; Toledo, Jorge R.; Rivas, Coralia I.; Vera, Juan C. [Department of Physiopathology, School of Biological Sciences, University of Concepcion, Concepcion (Chile); McNerney, Eileen M. [Molecular Endocrinology and Oncology Laboratory, University of Concepcion, Concepcion (Chile); Onate, Sergio A., E-mail: sergio.onate@udec.cl [Molecular Endocrinology and Oncology Laboratory, University of Concepcion, Concepcion (Chile); Department of Medical Specialties, School of Medicine, University of Concepcion, Concepcion (Chile); Department of Urology, State University of New York at Buffalo, NY (United States)

    2015-11-27

    Prostate cancer (CaP) bone metastasis is an early event that remains inactive until later-stage progression. Reduced levels of circulating androgens, due to andropause or androgen deprivation therapies, alter androgen receptor (AR) coactivator expression. Coactivators shift the balance towards enhanced AR-mediated gene transcription that promotes progression to androgen-resistance. Disruptions in coregulators may represent a molecular switch that reactivates latent bone metastasis. Changes in AR-mediated transcription in androgen-sensitive LNCaP and androgen-resistant C4-2 cells were analyzed for AR coregulator recruitment in co-culture with Saos-2 and THP-1. The Saos-2 cell line derived from human osteosarcoma and THP-1 cell line representing human monocytes were used to display osteoblast and osteoclast activity. Increased AR activity in androgen-resistant C4-2 was due to increased AR expression and SRC1/TIF2 recruitment and decreased SMRT/NCoR expression. AR activity in both cell types was decreased over 90% when co-cultured with Saos-2 or THP-1 due to dissociation of AR from the SRC1/TIF2 and SMRT/NCoR coregulators complex, in a ligand-dependent and cell-type specific manner. In the absence of androgens, Saos-2 decreased while THP-1 increased proliferation of LNCaP cells. In contrast, both Saos-2 and THP-1 decreased proliferation of C4-2 in absence and presence of androgens. Global changes in gene expression from both CaP cell lines identified potential cell cycle and androgen regulated genes as mechanisms for changes in cell proliferation and AR-mediated transactivation in the context of bone marrow stroma cells. - Highlights: • Decreased corepressor expression change AR in androgen-resistance prostate cancer. • Bone stroma-derived cells change AR coregulator recruitment in prostate cancer. • Bone stroma cells change cell proliferation in androgen-resistant cancer cells. • Global gene expression in CaP cells is modified by bone stroma cells in co

  6. Bone stroma-derived cells change coregulators recruitment to androgen receptor and decrease cell proliferation in androgen-sensitive and castration-resistant prostate cancer cells

    International Nuclear Information System (INIS)

    Villagran, Marcelo A.; Gutierrez-Castro, Francisco A.; Pantoja, Diego F.; Alarcon, Jose C.; Fariña, Macarena A.; Amigo, Romina F.; Muñoz-Godoy, Natalia A.; Pinilla, Mabel G.; Peña, Eduardo A.; Gonzalez-Chavarria, Ivan; Toledo, Jorge R.; Rivas, Coralia I.; Vera, Juan C.; McNerney, Eileen M.; Onate, Sergio A.

    2015-01-01

    Prostate cancer (CaP) bone metastasis is an early event that remains inactive until later-stage progression. Reduced levels of circulating androgens, due to andropause or androgen deprivation therapies, alter androgen receptor (AR) coactivator expression. Coactivators shift the balance towards enhanced AR-mediated gene transcription that promotes progression to androgen-resistance. Disruptions in coregulators may represent a molecular switch that reactivates latent bone metastasis. Changes in AR-mediated transcription in androgen-sensitive LNCaP and androgen-resistant C4-2 cells were analyzed for AR coregulator recruitment in co-culture with Saos-2 and THP-1. The Saos-2 cell line derived from human osteosarcoma and THP-1 cell line representing human monocytes were used to display osteoblast and osteoclast activity. Increased AR activity in androgen-resistant C4-2 was due to increased AR expression and SRC1/TIF2 recruitment and decreased SMRT/NCoR expression. AR activity in both cell types was decreased over 90% when co-cultured with Saos-2 or THP-1 due to dissociation of AR from the SRC1/TIF2 and SMRT/NCoR coregulators complex, in a ligand-dependent and cell-type specific manner. In the absence of androgens, Saos-2 decreased while THP-1 increased proliferation of LNCaP cells. In contrast, both Saos-2 and THP-1 decreased proliferation of C4-2 in absence and presence of androgens. Global changes in gene expression from both CaP cell lines identified potential cell cycle and androgen regulated genes as mechanisms for changes in cell proliferation and AR-mediated transactivation in the context of bone marrow stroma cells. - Highlights: • Decreased corepressor expression change AR in androgen-resistance prostate cancer. • Bone stroma-derived cells change AR coregulator recruitment in prostate cancer. • Bone stroma cells change cell proliferation in androgen-resistant cancer cells. • Global gene expression in CaP cells is modified by bone stroma cells in co

  7. 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.

  8. Docetaxel modulates the delayed rectifier potassium current (IK) and ATP-sensitive potassium current (IKATP) in human breast cancer cells.

    Science.gov (United States)

    Sun, Tao; Song, Zhi-Guo; Jiang, Da-Qing; Nie, Hong-Guang; Han, Dong-Yun

    2015-04-01

    Ion channel expression and activity may be affected during tumor development and cancer growth. Activation of potassium (K(+)) channels in human breast cancer cells is reported to be involved in cell cycle progression. In this study, we investigated the effects of docetaxel on the delayed rectifier potassium current (I K) and the ATP-sensitive potassium current (I KATP) in two human breast cancer cell lines, MCF-7 and MDA-MB-435S, using the whole-cell patch-clamp technique. Our results show that docetaxel inhibited the I K and I KATP in both cell lines in a dose-dependent manner. Compared with the control at a potential of +60 mV, treatment with docetaxel at doses of 0.1, 1, 5, and 10 µM significantly decreased the I K in MCF-7 cells by 16.1 ± 3.5, 30.2 ± 5.2, 42.5 ± 4.3, and 46.4 ± 9% (n = 5, P < 0.05), respectively and also decreased the I KATP at +50 mV. Similar results were observed in MDA-MB-435S cells. The G-V curves showed no significant changes after treatment of either MCF-7 or MDA-MB-435S cells with 10 μM docetaxel. The datas indicate that the possible mechanisms of I K and I KATP inhibition by docetaxel may be responsible for its effect on the proliferation of human breast cancer cells.

  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. Suppression of Homologous Recombination by insulin-like growth factor-1 inhibition sensitizes cancer cells to PARP inhibitors

    International Nuclear Information System (INIS)

    Amin, Oreekha; Beauchamp, Marie-Claude; Nader, Paul Abou; Laskov, Ido; Iqbal, Sanaa; Philip, Charles-André; Yasmeen, Amber; Gotlieb, Walter H.

    2015-01-01

    Impairment of homologous recombination (HR) is found in close to 50 % of ovarian and breast cancer. Tumors with BRCA1 mutations show increased expression of the Insulin-like growth factor type 1 receptor (IGF-1R). We previously have shown that inhibition of IGF-1R results in growth inhibition and apoptosis of ovarian tumor cells. In the current study, we aimed to investigate the correlation between HR and sensitivity to IGF-1R inhibition. Further, we hypothesized that IGF-1R inhibition might sensitize HR proficient cancers to Poly ADP ribose polymerase (PARP) inhibitors. Using ovarian and breast cancer cellular models with known BRCA1 status, we evaluated their HR functionality by RAD51 foci formation assay. The 50 % lethal concentration (LC50) of Insulin-like growth factor type 1 receptor kinase inhibitor (IGF-1Rki) in these cells was assessed, and western immunoblotting was performed to determine the expression of proteins involved in the IGF-1R pathway. Moreover, IGF-1R inhibitors were added on HR proficient cell lines to assess mRNA and protein expression of RAD51 by qPCR and western blot. Also, we explored the interaction between RAD51 and Insulin receptor substance 1 (IRS-1) by immunoprecipitation. Next, combination effect of IGF-1R and PARP inhibitors was evaluated by clonogenic assay. Cells with mutated/methylated BRCA1 showed an impaired HR function, and had an overactivation of the IGF-1R pathway. These cells were more sensitive to IGF-1R inhibition compared to HR proficient cells. In addition, the IGF-IR inhibitor reduced RAD51 expression at mRNA and protein levels in HR proficient cells, and sensitized these cells to PARP inhibitor. Targeting IGF-1R might lead to improved personalized therapeutic approaches in cancer patients with HR deficiency. Targeting both PARP and IGF-1R might increase the clinical efficacy in HR deficient patients and increase the population of patients who may benefit from PARP inhibitors

  11. Radiation sensitization by CAPE on human HeLa cells of cervical cancer

    International Nuclear Information System (INIS)

    Wang Xiaoqiang; Cao Jianping; Fan Saijun; Zun Wei; Huang Xiaofei; Liu Yang; Chen Xialin; Gong Xiaomei; Peng Xiaomei; Zeng Jing

    2009-01-01

    Objective: To study the radiosensitizing effect of caffic acid phenethyl ester (CAPE) on human cervical cancer HeLa cells. Methods: MTT assay was used to measure the relation between the inhibition effect and CAPE concentrations by CAPE with different concentrations on HeLa cells for 24 hours. HeLa cells were divided into the control and experimental groups, both of which were given 0, 2, 4, 6 and 8 Gy of 60Co γ-irradiation, respectively. The cell clones were counted. Meanwhile HeLa cells were divided into the control, CAPE, irradiation and combination groups. Flow cytometric analysis was adopted to detect the changes of cell cycle distribution induced by CAPE. Results: The inhibition rate of CAPE acting on Hela cells increased with concentrations (F=126. 49 ∼ 3654.88, P 0 ) (1.45 and 1.82 Gy) and the quasi-threshold dose (D q ) (1.89 and 3.21 Gy) of HeLa cells in experimental group decreased comparing with control group, SER was 1.26. Compared with the sole irradiation group, cells in G 2 /M phase of the CAPE group and the sole irradiation group increased (P 2 /M arrest and may be related to the inhibition of the sub-lethal damage repair. (authors)

  12. 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

    combinations with camptothecin or ionizing radiation. Furthermore, monitoring pARsylation and Rad51 foci formation as surrogate markers for PARP activity and HR, respectively, supported their candidacy for biomarkers of PARP-1i responses. As to resistance mechanisms, we confrmed the role of the multidrug......(ADp-ribose) polymerase-1 (PARP-1), an enzyme critical for repair pathways alternative to HR. While promising, treatment with PARP-1 inhibitors (PARP-1i) faces some hurdles, including (1) acquired resistance, (2) search for other sensitizing, non-BRCA1/2 cancer defects and (3) lack of biomarkers to predict response...

  13. 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.

  14. Hepcidin as a possible marker in determination of malignancy degree and sensitivity of breast cancer cells to cytostatic drugs.

    Science.gov (United States)

    Yalovenko, T M; Todor, I M; Lukianova, N Y; Chekhun, V F

    2016-06-01

    To investigate the role of hepcidin (Hepc) in the formation of cells malignant phenotype in vitro and its expression in the dyna-mics of growth of Walker-256 carcinosarcoma with different sensitivity to doxorubicin (Dox). The cell lines used in the analysis included T47D, MCF-7, MDA-MB-231, MDA-MB-468, MCF/CP, and MCF/Dox. Hepc expression was studied by immunocytochemical method. "Free" iron content was determined by EPR spectroscopy. Determination of Hepc expression in homogenates of tumor tissue and in blood serum of rats with Dox-sensitive and -resistant Walker-256 carcinosarcoma was performed. It was found that Hepc levels in breast cancer (BC) cells with high degree of malignancy (MDA-MB-231, MDA-MB-468) and drug-resistant phenotype (MCF/CP, MCF/Dox) were by 1.5-2 times higher (p < 0.05) in comparison with sensitive and less malignant BC cells. The development of drug-resistant phenotype in Walker-256 carcinosarcoma cells was accompanied by increasing of Hepc and "free" iron content (by 2.4 and 1.2 times, respectively). The data of in vitro and in vivo research evidenced on involvement of Hepc in formation of BC cells malignant phenotype and their resistance to Dox.

  15. The non-small cell lung cancer EGFR extracellular domain mutation, M277E, is oncogenic and drug-sensitive

    Directory of Open Access Journals (Sweden)

    Yu S

    2017-09-01

    Full Text Available Su Yu,1,2 Yang Zhang,1 Yunjian Pan,1 Chao Cheng,1,3 Yihua Sun,1,3 Haiquan Chen1–4 1Department of Thoracic Surgery, Fudan University Shanghai Cancer Center, Shanghai, China; 2Cancer Research Center, Fudan University Shanghai Cancer Center, Shanghai, China; 3Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China; 4Institutes of Biomedical Sciences, Fudan University, Shanghai, China Purpose: To identify novel oncogenic mutations in non-small cell lung cancer patient specimens that lack mutations in known targetable genes (“pan-negative” patients.Methods: Comprehensive mutational analyses were performed on 1,356 lung adenocarcinoma specimens. In this cohort of patients, common lung cancer oncogenic driver mutations were detected in the epidermal growth factor receptor (EGFR kinase domain, the human epidermal growth factor receptor 2 kinase domain, as well as the KRAS, BRAF, ALK, ROS1 and RET genes. A sub-cohort of pan-negative patient specimens was assayed for mutations in the EGFR extracellular domain (ECD. Additionally, EGFR mutant NIH-3T3 stable cell lines were constructed and assessed for protein content, anchorage-independent growth, and tumor formation in xenograft models to identify oncogenic mutations. BaF3 lymphocytes were also used to test sensitivities of the mutations to tyrosine kinase inhibitors.Results: In pan-negative lung adenocarcinoma cases, a novel oncogenic EGFR ECD mutation was identified (M277E. EGFR M277E mutations encoded oncoproteins that transformed NIH-3T3 cells to grow in the absence of exogenous epidermal growth factor. Transformation was further evidenced by anchorage-independent growth and tumor formation in immunocompromised xenograft mouse models. Finally, as seen in the canonical EGFR L858R mutation, the M277E mutation conferred sensitivity to both erlotinib and cetuximab in BaF3 cell lines and to erlotinib in xenograft models.Conclusion: Here, a new EGFR driver mutation, M277E

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

    International Nuclear Information System (INIS)

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

    2015-01-01

    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 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 6 cells/mL with a detection limit as low as 10 cells/mL for the detection of cancer cells

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

    Science.gov (United States)

    Díaz-Chávez, José; Fonseca-Sánchez, Miguel A; Arechaga-Ocampo, Elena; Flores-Pérez, Ali; Palacios-Rodríguez, Yadira; Domínguez-Gómez, Guadalupe; Marchat, Laurence A; Fuentes-Mera, Lizeth; Mendoza-Hernández, Guillermo; Gariglio, Patricio; López-Camarillo, César

    2013-01-01

    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 levels using natural

  20. 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.

  1. BAG3 sensitizes cancer cells exposed to DNA damaging agents via direct interaction with GRP78.

    Science.gov (United States)

    Kong, De-Hui; Zhang, Qiang; Meng, Xin; Zong, Zhi-Hong; Li, Chao; Liu, Bao-Qin; Guan, Yifu; Wang, Hua-Qin

    2013-12-01

    Bcl-2 associated athanogene 3 (BAG3) has a modular structure that contains a BAG domain, a WW domain, a proline-rich (PxxP) domain to mediate potential interactions with chaperons and other proteins that participate in more than one signal transduction. In search for novel interacting partners, the current study identified that 78kDa glucose-regulated protein (GRP78) was a novel partner interacting with BAG3. Interaction between GRP78 and BAG3 was confirmed by coimmunoprecipitation and glutathione S-transferase (GST) pulldown. We also identified that the ATPase domain of GRP78 and BAG domain of BAG3 mediated their interaction. Counterintuitive for a prosurvival protein, BAG3 was found to promote the cytotoxicity of breast cancer MCF7, thyroid cancer FRO and glioma U87 cells subjected to genotoxic stress. In addition, the current study demonstrated that BAG3 interfered with the formation of the antiapoptotic GRP78-procaspase-7 complex, which resulted in an increased genotoxic stress-induced cytotoxicity in cancer cells. Furthermore, overexpression of GRP78 significantly blocked the enhancing effects of BAG3 on activation of caspase-7 and induction of apoptosis by genotoxic stress. Overall, these results suggested that through direct interaction BAG3 could prevent the antiapoptotic effect of GRP78 upon genotoxic stress. © 2013.

  2. O6-alkylguanine-DNA-alkyltransferase activity and nitrosourea sensitivity in human cancer cell lines.

    OpenAIRE

    Walker, M. C.; Masters, J. R.; Margison, G. P.

    1992-01-01

    The DNA repair enzyme, O6-alkylguanine-DNA-alkyltransferase (ATase), is thought to be the principal mechanism controlling resistance to nitrosoureas and related alkylating agents. We compared the sensitivities of five human testis and five bladder tumour cell lines to two nitrosoureas (N-nitroso-N-methylurea (MNU) and mitozolomide) with cellular levels of ATase. Enzyme levels ranged from 3 to 206 fmol mg-1 protein (0.1 x 10(4) to 5.1 x 10(4) molecules/cell) in the testis lines and from 11 to ...

  3. Radio-sensitization of esophageal cancer EC9706 cells to X ray by histone deacetylase inhibiter Trichostatin A

    International Nuclear Information System (INIS)

    Lin Xiaoli; Qin Guangyong; Fang Huasheng; Zhang Fengqiu; Ya Huiyuan

    2009-01-01

    Cell apoptosis and the expression of DNA damage repair-related genes XRCC2, ATM and Lig4 were detected separately by flow cytometry analysis and real-time fluorescence quantitative (RT-PCR), in order to investigate the effect of Trichostatin A (TSA) pre-treatment on the radiosensitivity of esophageal cancer EC9706 cells to X ray in vitro. The results indicate that pre-irradiation exposure to TSA enhances cell apoptotic rate by X ray markedly (P<0.05) and the mRNA levels of XRCC2, ATM and Lig4 (except 8Gy) are up-regulated by X ray individually (P<0.05). TSA alone and TSA in combination with X ray all reduce mRNA levels of XRCC2, ATM and Lig4. In conclusions, TSA may radio-sensitize EC9706 cells to X ray by reducing mRNA levels of XRCC2, ATM and Lig4. (authors)

  4. Choline kinase-alpha by regulating cell aggressiveness and drug sensitivity is a potential druggable target for ovarian cancer.

    Science.gov (United States)

    Granata, A; Nicoletti, R; Tinaglia, V; De Cecco, L; Pisanu, M E; Ricci, A; Podo, F; Canevari, S; Iorio, E; Bagnoli, M; Mezzanzanica, D

    2014-01-21

    Aberrant choline metabolism has been proposed as a novel cancer hallmark. We recently showed that epithelial ovarian cancer (EOC) possesses an altered MRS-choline profile, characterised by increased phosphocholine (PCho) content to which mainly contribute over-expression and activation of choline kinase-alpha (ChoK-alpha). To assess its biological relevance, ChoK-alpha expression was downmodulated by transient RNA interference in EOC in vitro models. Gene expression profiling by microarray analysis and functional analysis was performed to identify the pathway/functions perturbed in ChoK-alpha-silenced cells, then validated by in vitro experiments. In silenced cells, compared with control, we observed: (I) a significant reduction of both CHKA transcript and ChoK-alpha protein expression; (II) a dramatic, proportional drop in PCho content ranging from 60 to 71%, as revealed by (1)H-magnetic spectroscopy analysis; (III) a 35-36% of cell growth inhibition, with no evidences of apoptosis or modification of the main cellular survival signalling pathways; (IV) 476 differentially expressed genes, including genes related to lipid metabolism. Ingenuity pathway analysis identified cellular functions related to cell death and cellular proliferation and movement as the most perturbed. Accordingly, CHKA-silenced cells displayed a significant delay in wound repair, a reduced migration and invasion capability were also observed. Furthermore, although CHKA silencing did not directly induce cell death, a significant increase of sensitivity to platinum, paclitaxel and doxorubicin was observed even in a drug-resistant context. We showed for the first time in EOC that CHKA downregulation significantly decreased the aggressive EOC cell behaviour also affecting cells' sensitivity to drug treatment. These observations open the way to further analysis for ChoK-alpha validation as a new EOC therapeutic target to be used alone or in combination with conventional drugs.

  5. 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.

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

    International Nuclear Information System (INIS)

    Kim, In-Gyu; Lee, Jae-Ha; Kim, Seo-Yoen; Kim, Jeong-Yul; Cho, Eun-Wie

    2014-01-01

    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

  7. Metformin sensitizes chemotherapy by targeting cancer stem cells and the mTOR pathway in esophageal cancer

    OpenAIRE

    HONJO, SOICHIRO; AJANI, JAFFER A.; SCOTT, AILING W.; CHEN, QIONGRONG; SKINNER, HEATH D.; STROEHLEIN, JOHN; JOHNSON, RANDY L.; SONG, SHUMEI

    2014-01-01

    Our clinical study indicates esophageal adenocarcinoma patients on metformin had a better treatment response than those without metformin. However, the effects of metformin and the mechanisms of its action in esophageal cancer (EC) are unclear. EC cell lines were used to assess the effects of metformin alone or in combination with 5-fluorouracil on survival and apoptosis. RPPA proteomic array and immunoblots were used to identify signaling affected by metformin. Standard descriptive statistic...

  8. 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

    OpenAIRE

    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 s...

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

    International Nuclear Information System (INIS)

    Yavari, Kamal; Taghikhani, Mohammad; Mesbah-Namin, Seyed A.; Maragheh, Mohammad Ghannadi; Babaei, Mohammad Hosein; Arfaee, Ali Jabbary; Madani, Hossein; Mirzaei, Hamid Reza

    2010-01-01

    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

  10. Role of the NRP-1-mediated VEGFR2-independent pathway on radiation sensitivity of non-small cell lung cancer cells.

    Science.gov (United States)

    Hu, Chenxi; Zhu, Panrong; Xia, Youyou; Hui, Kaiyuan; Wang, Mei; Jiang, Xiaodong

    2018-07-01

    To determine if inhibiting neuropilin-1 (NRP-1) affects the radiosensitivity of NSCLC cells through a vascular endothelial growth factor receptor 2 (VEGFR2)-independent pathway, and to assess the underlying mechanisms. The expression of VEGFR2, NRP-1, related signaling molecules, abelson murine leukemia viral oncogene homolog 1 (ABL-1), and RAD51 were determined by RT-PCR and Western blotting, respectively. Radiosensitivity was assessed using the colony-forming assay, and the cell apoptosis were analyzed by flow cytometry. We selected two cell lines with high expression levels of VEGFR2, including Calu-1 cells that have high NRP-1 expression, and H358 cells that have low NRP-1 expression. Upon inhibition of p-VEGFR2 by apatinib in Calu-1 cells, the expression of NRP-1 protein and other related proteins in the pathway was still high. Upon NRP-1 siRNA treatment, the expression of both NRP-1 and RAD51 decreased (p cells treated with NRP-1 siRNA exhibited significantly higher apoptosis and radiation sensitivity in radiation therapy compared to Calu-1 cells treated with apatinib alone (p cells with NRP-1 overexpression was similar to the control group regardless of VEGFR2 inhibition. We demonstrated that when VEGFR2 was inhibited, NRP-1 appeared to regulate RAD51 expression through the VEGFR2-independent ABL-1 pathway, consequently regulating radiation sensitivity. In addition, the combined inhibition of VEGFR2 and NRP-1 appears to sensitize cancer cells to radiation.

  11. In vitro radiation and chemotherapy sensitivity of established cell lines of human small cell lung cancer and its large cell morphological variants

    International Nuclear Information System (INIS)

    Carney, D.N.; Mitchell, J.B.; Kinsella, T.J.

    1983-01-01

    The in vitro response to radiation and chemotherapeutic drugs of cell lines established from 7 patients with small cell (SC) lung cancer were tested using a soft agarose clonogenic assay. Five cell lines retained the typical morphological and biochemical amine precursor uptake decarboxylation characteristics of SC, while two cell lines had undergone ''transformation'' to large cell (LC) morphological variants with loss of amine precursor uptake decarboxylation cell characteristics of SC. The radiation survival curves for the SC lines were characterized by D0 values ranging from 51 to 140 rads and extrapolation values (n) ranging from 1.0 to 3.3. While the D0 values of the radiation survival curves of the LC variants were similar (91 and 80 rads), the extrapolation values were 5.6 and 11.1 In vitro chemosensitivity testing of the cell lines revealed an excellent correlation between prior treatment status of the patient and in vitro sensitivity or resistance. No correlation was observed between in vitro chemosensitivity and radiation response. These data suggest that transformation of SC to LC with loss of amine precursor uptake and decarboxylation characteristics is associated with a marked increase in radiation resistance (n) in vitro. The observation of a 2- to 5-fold increase in survival of the LC compared to the SC lines following 200 rads suggests that the use of larger daily radiation fractions and/or radiation-sensitizing drugs might lead to a significantly greater clinical response in patients with LC morphology. This clinical approach may have a major impact on patient response and survival

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

    Science.gov (United States)

    Chen, Yu-An; Lien, Hsiu-Man; 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, 3,4',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.

  13. 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.

  14. AT-101 enhances gefitinib sensitivity in non-small cell lung cancer with EGFR T790M mutations

    International Nuclear Information System (INIS)

    Zhao, Ren; Zhou, Shun; Xia, Bing; Zhang, Cui-ying; Hai, Ping; Zhe, Hong; Wang, Yan-yang

    2016-01-01

    Although epidermal growth factor receptor tyrosine kinase inhibitors (EGFR TKIs) have become the standard care of patients with advanced EGFR-mutant non-small cell lung cancer (NSCLC), development of acquired resistance is inevitable. A secondary mutation of threonine 790 (T790M) is associated with approximately half of the cases of acquired resistance. Strategies or agents to overcome this type of resistance are still limited. In this study, enhanced antitumor effect of AT-101, a-pan-Bcl-2 inhibitor, on gefitinib was explored in NSCLC with T790M mutation. The effect of cotreatment with AT-101 and gefitinib on the viability of NSCLC cell lines harboring acquired T790M mutation was investigated using the MTT assay. The cellular apoptosis of NSCLC cells after cotreatment with AT-101 and gefitinib was assessed by FITC-annexin V/PI assay and Western blots analysis. The potential underlying mechanisms of the enhanced therapeutic effect for AT-101 was also studied using Western blots analysis. The in vivo anti-cancer efficacy of the combination with AT-101 and gefitinib was examined in a mouse xenograft model. In this study, we found that treatment with AT-101 in combination with gefitinib significantly inhibited cell proliferation, as well as promoted apoptosis of EGFR TKIs resistant lung cancer cells. The apoptotic effects of the use of AT-101 was related to the blocking of antiapoptotic protein: Bcl-2, Bcl-xl, and Mcl-1 and downregrulation of the molecules in EGFR pathway. The observed enhancements of tumor growth suppression in xenografts supported the reverse effect of AT-101 in NSCLC with T790M mutation, which has been found in in vitro studies before. AT-101 enhances gefitinib sensitivity in NSCLC with EGFR T790M mutations. The addition of AT-101 to gefitinib is a promising strategy to overcome EGFR TKIs resistance in NSCLC with EGFR T790M mutations

  15. 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.

  16. 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. © Georg Thieme Verlag KG Stuttgart · New York.

  17. [Effect of sodium phenylbutyrate on the sensitivity of PC3/DTX-resistant prostate cancer cells to docetaxel].

    Science.gov (United States)

    Xu, Ya-Wen; Zheng, Shao-Bo; Chen, Bin-Sheng; Wen, Yong; Zhu, Shan-Wen

    To investigate the effect of sodium phenylbutyrate (SPB) in modulating docetaxel resistance in human prostate cancer cells in vitro. A PC3/docetaxel-resistant human prostate cancer cell line PC3/DTX was induced and examined for proliferation, viability, and cell inhibition rate in the presence of SPB. The concentration of concentration of docetaxel required to kill 50% of PC3/DTX cells incubated with 0, 1, 2, and 4 mmol/L SPB was determined using MTT assay. Cell apoptosis rate was analyzed with flow cytometry and the cellular expressions of p21, cyclin D1 and survivin proteins were detected using Western blotting. Treatment of PC3/DTX cells with 0, 1, 2, and 4 mmol/L of SPB for 48 h resulted in cell viabilities of (99.85∓2.69)%, (84.68∓3.87)%, (68.65∓4.54)% and (43.54∓5.69)%, and cell inhibition rates of (10.69∓3.65)%, (25.78∓4.58)%, (54.68∓3.98)% and (69.84∓6.54)%, respectively (P<0.05). The concentration of docetaxel required to kill 50% of PC3/DTX cells cultured in the presence of with 0, 1, 2, and 4 mmol/L SPB was 135.98∓2.69, 109.65∓3.87, 87.65∓3.84 and 64.62∓2.98 nmol/L, respectively (P<0.05), and the cell apoptosis rates were (7.2∓0.8)%, (10.2∓0.9)%, (19.8∓2.1)% and (27.4∓2.5)%, respectively. SPB treatment promoted the protein expression of p21 and suppressed the expressions of cyclin D1 and survivin in PC3/DTX cells. SPB can affect the expressions of p21, cyclin D1, and survivin in PC3/DTX cells and increase the sensitivity to the drug-resistant cells to docetaxel.

  18. Cypripedin, a phenanthrenequinone from Dendrobium densiflorum, sensitizes non-small cell lung cancer H460 cells to cisplatin-mediated apoptosis.

    Science.gov (United States)

    Wattanathamsan, Onsurang; Treesuwan, Surassawadee; Sritularak, Boonchoo; Pongrakhananon, Varisa

    2018-03-01

    The life-threatening potential of lung cancer has increased over the years due to its acquisition of chemotherapeutic resistance, especially to cisplatin, a first-line therapy. In response to this development, researchers have turned their attention to several compounds derived from natural origins, including cypripedin (CYP), a phenanthrenequinone substance extracted from Dendrobium densiflorum. The aim of the present study was to investigate the ability of CYP to induce apoptosis and enhance cisplatin-mediated death of human lung cancer NCI-H460 cells using cell viability and apoptosis assays. The induction of apoptosis by CYP was observed at a concentration of > 50 μM with the appearance of morphological changes, including DNA condensation and chromatin fragmentation. Together with, CYP was able to activate caspase-3 and downregulate the anti-apoptotic proteins Bcl-2 and Bcl-xL. Also, a non-cytotoxic dose of CYP synergistically potentiated the effect of cisplatin in non-small cell lung cancer line H460 cells, which clearly exhibited the apoptotic phenotype. Western blot analysis revealed that the underlying mechanism involved the downregulation of anti-apoptotic Bcl-xL, whereas the levels of other apoptotic regulatory proteins were not altered. This study provides interesting information on the potent effect of CYP as a chemotherapeutic sensitizer that could be further developed to improve the clinical outcomes of lung cancer patients.

  19. 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 IC 50 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. ©2016 American Association for Cancer Research.

  20. 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.

  1. Down-regulation of GRP78 is associated with the sensitivity of chemotherapy to VP-16 in small cell lung cancer NCI-H446 cells

    International Nuclear Information System (INIS)

    Wang, Yingyan; Wang, Wei; Wang, Siyan; Wang, Jiarui; Shao, Shujuan; Wang, Qi

    2008-01-01

    Chemotherapy resistance remains a major obstacle for the treatment of small cell lung cancer (SCLC). Glucose-regulated protein 78 (GRP78), an endoplasmic reticulum chaperone, plays a critical role in chemotherapy resistance in some cancers. However, whether the suppression of the chaperone can enhance the sensitivity of chemotherapy in SCLC is still unclear. The SCLC NCI-H446 cells were divided into three groups: BAPTA-AM→A23187-treated group, A23187-treated group and control-group. Immunofluorescence, western blot and RT-PCR were used to assess the expression of GRP78 at both protein and mRNA levels. Cell apoptosis and the cell cycle distributions of the cells were analyzed by flow cytometry in order to evaluate the therapeutic sensitivity to VP-16. The expression of GRP78 at both protein and mRNA levels in the BAPTA-AM→A23187-treated cells dramatically decreased as compared to that in both A23187-treated and control groups. After treatment by VP-16, the percentage of apoptotic cells in BAPTA-AM→A23187-treated cells were: 33.4 ± 1.01%, 48.2 ± 1.77%, 53.0 ± 1.43%, 56.5 ± 2.13%, respectively, corresponding to the concentrations of BAPTA-AM 10, 15, 25, 40 μM, which was statistically significant high in comparison with the A23187-treated group and untreated-group (7.18 ± 1.03% and 27.8 ± 1.45%, respectively, p < 0.05). The results from analysis of cell cycle distribution showed that there was a significantly decreased in G 1 phase and a dramatically increased in S phase for the BAPTA-AM→A23187-treated cells as compared with the untreated cells. BAPTA-AM is a strong inhibitor of GRP78 in the NCI-H446 cell line, the down-regulation of GRP78 can significantly increase the sensitivity to VP-16. The suppression of GRP78 may offer a new surrogated therapeutic approach to the clinical management of lung cancer

  2. Sensitization of human cancer cells to gemcitabine by the Chk1 inhibitor MK-8776: cell cycle perturbation and impact of administration schedule in vitro and in vivo

    International Nuclear Information System (INIS)

    Montano, Ryan; Thompson, Ruth; Chung, Injae; Hou, Huagang; Khan, Nadeem; Eastman, Alan

    2013-01-01

    Chk1 inhibitors have emerged as promising anticancer therapeutic agents particularly when combined with antimetabolites such as gemcitabine, cytarabine or hydroxyurea. Here, we address the importance of appropriate drug scheduling when gemcitabine is combined with the Chk1 inhibitor MK-8776, and the mechanisms involved in the schedule dependence. Growth inhibition induced by gemcitabine plus MK-8776 was assessed across multiple cancer cell lines. Experiments used clinically relevant “bolus” administration of both drugs rather than continuous drug exposures. We assessed the effect of different treatment schedules on cell cycle perturbation and tumor cell growth in vitro and in xenograft tumor models. MK-8776 induced an average 7-fold sensitization to gemcitabine in 16 cancer cell lines. The time of MK-8776 administration significantly affected the response of tumor cells to gemcitabine. Although gemcitabine induced rapid cell cycle arrest, the stalled replication forks were not initially dependent on Chk1 for stability. By 18 h, RAD51 was loaded onto DNA indicative of homologous recombination. Inhibition of Chk1 at 18 h rapidly dissociated RAD51 leading to the collapse of replication forks and cell death. Addition of MK-8776 from 18–24 h after a 6-h incubation with gemcitabine induced much greater sensitization than if the two drugs were incubated concurrently for 6 h. The ability of this short incubation with MK-8776 to sensitize cells is critical because of the short half-life of MK-8776 in patients’ plasma. Cell cycle perturbation was also assessed in human pancreas tumor xenografts in mice. There was a dramatic accumulation of cells in S/G 2 phase 18 h after gemcitabine administration, but cells had started to recover by 42 h. Administration of MK-8776 18 h after gemcitabine caused significantly delayed tumor growth compared to either drug alone, or when the two drugs were administered with only a 30 min interval. There are two reasons why delayed

  3. Anthelminthic drug niclosamide sensitizes the responsiveness of cervical cancer cells to paclitaxel via oxidative stress-mediated mTOR inhibition

    International Nuclear Information System (INIS)

    Chen, Liping; Wang, Li; Shen, Haibin; Lin, Hui; Li, Dan

    2017-01-01

    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. - Highlights: • Niclosamide is active against cervical cancer cells in vitro and in vivo. • Niclosamide sensitizes cervical cancer cell response to paclitaxel. • Niclosamide induces mitochondrial dysfunction and oxidative damage. • Niclosamide inhibits mTOR signaling in an oxidative stress-dependent manner.

  4. Silencing MED1 sensitizes breast cancer cells to pure anti-estrogen fulvestrant in vitro and in vivo.

    Directory of Open Access Journals (Sweden)

    Lijiang Zhang

    Full Text Available Pure anti-estrogen fulvestrant has been shown to be a promising ER antagonist for locally advanced and metastatic breast cancer. Unfortunately, a significant proportion of patients developed resistance to this type of endocrine therapy but the molecular mechanisms governing cellular responsiveness to this agent remain poorly understood. Here, we've reported that knockdown of estrogen receptor coactivator MED1 sensitized fulvestrant resistance breast cancer cells to fulvestrant treatment. We found that MED1 knockdown further promoted cell cycle arrest induced by fulvestrant. Using an orthotopic xenograft mouse model, we found that knockdown of MED1 significantly reduced tumor growth in mice. Importantly, knockdown of MED1 further potentiated tumor growth inhibition by fulvestrant. Mechanistic studies indicated that combination of fulvestrant treatment and MED1 knockdown is able to cooperatively inhibit the expression of ER target genes. Chromatin immunoprecipitation experiments further supported a role for MED1 in regulating the recruitment of RNA polymerase II and transcriptional corepressor HDAC1 on endogenous ER target gene promoter in the presence of fulvestrant. These results demonstrate a role for MED1 in mediating resistance to the pure anti-estrogen fulvestrant both in vitro and in vivo.

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

    Science.gov (United States)

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

    2017-10-01

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

  6. Functional inhibition of Ubiquitin conjugating Enzyme (UBE2C) reduces proliferation and sensitizes cervical and breast cancer cells to radiation, doxorubicin, tamoxifen and letrozole

    International Nuclear Information System (INIS)

    Bose, Mayil Vahanan; Rawat, Akhilesh; Gopisetty, Gopal; Thangarajan, Rajkumar; Ganesharaja, Selvaluxmy

    2014-01-01

    Cervical cancer is the second most common cancer in women, worldwide. About 80% of cervical cancer cases occur in developing countries. Breast cancer has overtaken cervical cancer in most of the urban centers in India. In recent years, interest in the role of Ubiquitin conjugating Enzyme E2C (UBE2C) in cancer has shown a dramatic increase. Several studies have reported UBE2C as a potential oncogene and therapeutic target. The objective of the study was to elucidate radiation and chemo-sensitivity in response to functional inhibition of UBE2C in cervical and breast cancer cell lines. Taqman Real time PCR was performed to measure UBE2C levels in cervical and breast cancer cell lines. A dominant negative form of UBE2C (DN-UBE2C) was used to functionally inhibit wild type UBE2C. Cell proliferation and anchorage independent growth were measured by colorimetric assay and soft agar assay respectively. Radiation and chemo response of cell lines were assessed by colorimetric assay and clonogenic assay. Difference in sensitivity to radiation was observed among the cervical cancer cell lines studied. The growth rate of SiHa and HeLa transfected with DN- UBE2C was significantly reduced compared to vector control. Further, DN-UBE2C mediated radio-sensitivity was correlated with a significant decrease in resistance to radiation by SiHa and HeLa cells after transfection when compared to control cultures. Similarly, both the growth rate and the anchorage independent growth of MCF7 and MDAMB231 cells transfected with DN-UBE2C were significantly reduced compared to cells transfected with vector alone. MCF7 and MDAMB231 cells expressing DN-UBE2C were significantly more sensitive to different doses of radiation and doxorubicin compared to controls. In addition, DN-UBE2C transfected MCF7 cells were more sensitive to inhibition by tamoxifen and letrozole compared to vector controls. These results suggest that UBE2C can be used as a potential therapeutic target for cervical and breast

  7. Silencing of the transcription factor STAT3 sensitizes lung cancer cells to DNA damaging drugs, but not to TNFα- and NK cytotoxicity

    Energy Technology Data Exchange (ETDEWEB)

    Kulesza, Dorota W. [Laboratory of Transcription Regulation, Department of Cell Biology, The Nencki Institute of Experimental Biology, Warsaw (Poland); Postgraduate School of Molecular Medicine, Warsaw Medical University, Warsaw (Poland); Carré, Thibault; Chouaib, Salem [Unité INSERM U753, Institut de Cancérologie Gustave Roussy, Villejuif Cedex (France); Kaminska, Bozena, E-mail: bozenakk@nencki.gov.pl [Laboratory of Transcription Regulation, Department of Cell Biology, The Nencki Institute of Experimental Biology, Warsaw (Poland)

    2013-02-15

    Transcription factor STAT3 (Signal Transducers and Activators of Transcription 3) is persistently active in human tumors and may contribute to tumor progression. Inhibition of STAT3 expression/activity could be a good strategy to modulate tumor cell survival and responses to cancer chemotherapeutics or immune cytotoxicity. We silenced STAT3 expression in human A549 lung cancer cells to elucidate its role in cell survival and resistance to chemotherapeutics, TNFα and natural killer (NK)-mediated cytotoxicity. We demonstrate that STAT3 is not essential for basal survival and proliferation of A549 cancer cells. Stable silencing of STAT3 expression sensitized A549 cells to DNA damaging chemotherapeutics doxorubicin and cisplatin in a p53-independent manner. Sensitization to DNA damage-inducing chemotherapeutics could be due to down-regulation of the Bcl-xL expression in STAT3 depleted cells. In contrast, knockdown of STAT3 in cancer cells did not modulate responses to TNFα and NK-mediated cytotoxicity. We found that STAT3 depletion increased the NFκB activity likely providing the compensatory, pro-survival signal. The treatment with TNFα, but not doxorubicin, enhanced this effect. We conclude that STAT3 is not crucial for the control of basal cell proliferation and survival of lung carcinoma cells but modulates susceptibility to DNA damaging chemotherapeutics by regulation of intrinsic pro-survival pathways. - Highlights: ► STAT3 silencing is negligent for basal lung cancer cell viability and proliferation. ► STAT3 depletion sensitizes lung cancer cells to DNA damaging chemotherapeutics. ► STAT3 depletion has no effect on susceptibility to extrinsic apoptosis inducers. ► Increased pro-survival NFκB activity may compensate for STAT3 depletion.

  8. Resveratrol-Induced Downregulation of NAF-1 Enhances the Sensitivity of Pancreatic Cancer Cells to Gemcitabine via the ROS/Nrf2 Signaling Pathways

    Directory of Open Access Journals (Sweden)

    Liang Cheng

    2018-01-01

    Full Text Available NAF-1 (nutrient-deprivation autophagy factor-1, which is an outer mitochondrial membrane protein, is known to play important roles in calcium metabolism, antiapoptosis, and antiautophagy. Resveratrol, a natural polyphenolic compound, is considered as a potent anticancer agent. Nevertheless, the molecular mechanisms underlying the effects of resveratrol and NAF-1 and their mediation of drug resistance in pancreatic cancer remain unclear. Here, we demonstrate that resveratrol suppresses the expression of NAF-1 in pancreatic cancer cells by inducing cellular reactive oxygen species (ROS accumulation and activating Nrf2 signaling. In addition, the knockdown of NAF-1 activates apoptosis and impedes the proliferation of pancreatic cancer cells. More importantly, the targeting of NAF-1 by resveratrol can improve the sensitivity of pancreatic cancer cells to gemcitabine. These results highlight the significance of strategies that target NAF-1, which may enhance the efficacy of gemcitabine in pancreatic cancer therapy.

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

    Czech Academy of Sciences Publication Activity Database

    Pavlíková, N.; Bartoňová, I.; Balušíková, K.; Kopperová, D.; Halada, Petr; Kovář, J.

    2015-01-01

    Roč. 333, č. 1 (2015), s. 1-10 ISSN 0014-4827 Institutional support: RVO:61388971 Keywords : Breast cancer * Taxane resistance * 2-D electrophoresis Subject RIV: CE - Biochemistry Impact factor: 3.378, year: 2015

  10. Tumor Suppression and Sensitization to Taxol Induced Apoptosis of E1A In Breast Cancer Cells

    National Research Council Canada - National Science Library

    Liao, Yong

    2004-01-01

    .... Because a phase I E1A gene therapy protocol for human breast and ovarian cancers was completed and a phase II clinical trial is undergoing, we also plan to develop an alternative E1A mutant construct...

  11. Epigenetics-related genes in prostate cancer: expression profile in prostate cancer tissues, androgen-sensitive and -insensitive cell lines.

    Science.gov (United States)

    Shaikhibrahim, Zaki; Lindstrot, Andreas; Ochsenfahrt, Jacqueline; Fuchs, Kerstin; Wernert, Nicolas

    2013-01-01

    Epigenetic changes have been suggested to drive prostate cancer (PCa) development and progression. Therefore, in this study, we aimed to identify novel epigenetics-related genes in PCa tissues, and to examine their expression in metastatic PCa cell lines. We analyzed the expression of epigenetics-related genes via a clustering analysis based on gene function in moderately and poorly differentiated PCa glands compared to normal glands of the peripheral zone (prostate proper) from PCa patients using Whole Human Genome Oligo Microarrays. Our analysis identified 12 epigenetics-related genes with a more than 2-fold increase or decrease in expression and a p-value epigenetics-related genes that we identified in primary PCa tissues may provide further insight into the role that epigenetic changes play in PCa. Moreover, some of the genes that we identified may play important roles in primary PCa and metastasis, in primary PCa only, or in metastasis only. Follow-up studies are required to investigate the functional role and the role that the expression of these genes play in the outcome and progression of PCa using tissue microarrays.

  12. Trichostatin A (TSA) sensitizes the human prostatic cancer cell line DU145 to death receptor ligands treatment.

    Science.gov (United States)

    Taghiyev, Agshin F; Guseva, Natalya V; Sturm, Mary T; Rokhlin, Oskar W; Cohen, Michael B

    2005-04-01

    The human prostatic carcinoma cell line DU145 has previously been found to be resistant to treatment with TNF-family ligands. However, TRAIL, TNF-alpha and anti-Fas antibodies (Ab) treatment in combination with the histone deacetylase inhibitor Trichostatin A (TSA) converted the phenotype of DU145 from resistant to sensitive. TSA induced 15% cell death but simultaneous treatment with TRAIL, TNF-alpha and anti-Fas Ab resulted in 55%, 70% and 40% cell death, respectively. Simultaneous treatment did not increase the level of TSA-induced histone acetylation, but induced the release of acetylated histones from chromatin into the cytosol. This release was caspase dependent since it was abrogated by Z-VAD-fmk. In addition, treatment with TSA induced caspase-9 activation and resulted in the release of cytochrome c and Smac/DIABLO from mitochondria. To further investigate the role of caspase-9 in TSA-mediated apoptosis we used two different approaches: (1) cells were pretreated with the caspase-9 inhibitor Z-LEHD-fmk, and (2) cells were transfected with a dominant-negative form of caspase-9. Both approaches gave similar results: cells became resistant to treatment with TSA. These data indicate that TSA mediates its effect via the mitochondrial pathway. This was confirmed by examining DU145 overexpressing Bcl-2. These transfectants were resistant to TSA treatment. Taken together, our data shows that only simultaneous treatment with TNF-family ligands and TSA in DU145 resulted in caspase activity sufficient to induce apoptosis. The combination of TSA and TNF-family ligands could potentially be the basis for the treatment of prostate cancer.

  13. 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.

  14. 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.

  15. Cost-benefit of minimally invasive staging of non-small cell lung cancer: a decision tree sensitivity analysis.

    Science.gov (United States)

    Steinfort, Daniel P; Liew, Danny; Conron, Matthew; Hutchinson, Anastasia F; Irving, Louis B

    2010-10-01

    Accurate staging of non-small cell lung cancer (NSCLC) is critical for optimal management. Minimally invasive pathologic assessment of mediastinal lymphadenopathy is increasingly being performed. The cost-benefit (minimization of health care costs) of such approaches, in comparison with traditional surgical methods, is yet to be established. Decision-tree analysis was applied to compare downstream costs of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA), conventional TBNA, and surgical mediastinoscopy. Calculations were based on real costs derived from actual patient data at a major teaching hospital in Melbourne, Australia. One- and two-way sensitivity analyses were undertaken to account for potential variation in input parameter values. For the base-case analysis, initial evaluation with EBUS-TBNA (with negative results being surgically confirmed) was the most cost-beneficial approach (AU$2961) in comparison with EBUS-TBNA (negative results not surgically confirmed) ($3344), conventional TBNA ($3754), and mediastinoscopy ($8859). The sensitivity of EBUS-TBNA for detecting disease had the largest impact on cost, whereas the prevalence of mediastinal lymph node metastases determined whether surgical confirmation of negative EBUS-TBNA results remained cost-beneficial. Our study confirms that minimally invasive staging of NSCLC is cost-beneficial in comparison with traditional surgical techniques. EBUS-TBNA was the most cost-beneficial approach for mediastinal staging of patients with NSCLC across all studied parameters.

  16. Differential Sensitivities of Fast- and Slow-Cycling Cancer Cells to Inosine Monophosphate Dehydrogenase 2 Inhibition by Mycophenolic Acid

    Science.gov (United States)

    Chen, Kan; Cao, Wanlu; Li, Juan; Sprengers, Dave; Hernanda, Pratika Y; Kong, Xiangdong; van der Laan, Luc JW; Man, Kwan; Kwekkeboom, Jaap; Metselaar, Herold J; Peppelenbosch, Maikel P; Pan, Qiuwei

    2015-01-01

    As uncontrolled cell proliferation requires nucleotide biosynthesis, inhibiting enzymes that mediate nucleotide biosynthesis constitutes a rational approach to the management of oncological diseases. In practice, however, results of this strategy are mixed and thus elucidation of the mechanisms by which cancer cells evade the effect of nucleotide biosynthesis restriction is urgently needed. Here we explored the notion that intrinsic differences in cancer cell cycle velocity are important in the resistance toward inhibition of inosine monophosphate dehydrogenase (IMPDH) by mycophenolic acid (MPA). In short-term experiments, MPA treatment of fast-growing cancer cells effectively elicited G0/G1 arrest and provoked apoptosis, thus inhibiting cell proliferation and colony formation. Forced expression of a mutated IMPDH2, lacking a binding site for MPA but retaining enzymatic activity, resulted in complete resistance of cancer cells to MPA. In nude mice subcutaneously engrafted with HeLa cells, MPA moderately delayed tumor formation by inhibiting cell proliferation and inducing apoptosis. Importantly, we developed a lentiviral vector–based Tet-on label-retaining system that enables to identify, isolate and functionally characterize slow-cycling or so-called label-retaining cells (LRCs) in vitro and in vivo. We surprisingly found the presence of LRCs in fast-growing tumors. LRCs were superior in colony formation, tumor initiation and resistance to MPA as compared with fast-cycling cells. Thus, the slow-cycling compartment of cancer seems predominantly responsible for resistance to MPA. PMID:26467706

  17. Blocking anaplerotic entry of glutamine into the TCA cycle sensitizes K-Ras mutant cancer cells to cytotoxic drugs.

    Science.gov (United States)

    Saqcena, M; Mukhopadhyay, S; Hosny, C; Alhamed, A; Chatterjee, A; Foster, D A

    2015-05-14

    Cancer cells undergo a metabolic transformation that allows for increased anabolic demands, wherein glycolytic and tricarboxylic acid (TCA) cycle intermediates are shunted away for the synthesis of biological molecules required for cell growth and division. One of the key shunts is the exit of citrate from the mitochondria and the TCA cycle for the generation of cytosolic acetyl-coenzyme A that can be used for fatty acid and cholesterol biosynthesis. With the loss of mitochondrial citrate, cancer cells rely on the 'conditionally essential' amino acid glutamine (Q) as an anaplerotic carbon source for TCA cycle intermediates. Although Q deprivation causes G1 cell cycle arrest in non-transformed cells, its impact on the cancer cell cycle is not well characterized. We report here a correlation between bypass of the Q-dependent G1 checkpoint and cancer cells harboring K-Ras mutations. Instead of arresting in G1 in response to Q-deprivation, K-Ras-driven cancer cells arrest in either S- or G2/M-phase. Inhibition of K-Ras effector pathways was able to revert cells to G1 arrest upon Q deprivation. Blocking anaplerotic utilization of Q mimicked Q deprivation--causing S- and G2/M-phase arrest in K-Ras mutant cancer cells. Significantly, Q deprivation or suppression of anaplerotic Q utilization created synthetic lethality to the cell cycle phase-specific cytotoxic drugs, capecitabine and paclitaxel. These data suggest that disabling of the G1 Q checkpoint could represent a novel vulnerability of cancer cells harboring K-Ras and possibly other mutations that disable the Q-dependent checkpoint.

  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. Sensitivity of docetaxel-resistant MCF-7 breast cancer cells to microtubule-destabilizing agents including vinca alkaloids and colchicine-site binding agents.

    Directory of Open Access Journals (Sweden)

    Richard C Wang

    Full Text Available One of the main reasons for disease recurrence in the curative breast cancer treatment setting is the development of drug resistance. Microtubule targeted agents (MTAs are among the most commonly used drugs for the treatment of breaset cancer and therefore overcoming taxane resistance is of primary clinical importance. Our group has previously demonstrated that the microtubule dynamics of docetaxel-resistant MCF-7TXT cells are insensitivity to docetaxel due to the distinct expression profiles of β-tubulin isotypes in addition to the high expression of p-glycoprotein (ABCB1. In the present investigation we examined whether taxane-resistant breast cancer cells are more sensitive to microtubule destabilizing agents including vinca alkaloids and colchicine-site binding agents (CSBAs than the non-resistant cells.Two isogenic MCF-7 breast cancer cell lines were selected for resistance to docetaxel (MCF-7TXT and the wild type parental cell line (MCF-7CC to examine if taxane-resistant breast cancer cells are sensitive to microtubule-destabilizing agents including vinca alkaloids and CSBAs. Cytotoxicity assays, immunoblotting, indirect immunofluorescence and live imaging were used to study drug resistance, apoptosis, mitotic arrest, microtubule formation, and microtubule dynamics.MCF-7TXT cells were demonstrated to be cross resistant to vinca alkaloids, but were more sensitive to treatment with colchicine compared to parental non-resistant MCF-7CC cells. Cytotoxicity assays indicated that the IC50 of MCF-7TXT cell to vinorelbine and vinblastine was more than 6 and 3 times higher, respectively, than that of MCF-7CC cells. By contrast, the IC50 of MCF-7TXT cell for colchincine was 4 times lower than that of MCF-7CC cells. Indirect immunofluorescence showed that all MTAs induced the disorganization of microtubules and the chromatin morphology and interestingly each with a unique pattern. In terms of microtubule and chromain morphology, MCF-7TXT cells were

  20. Ionizing radiation and nitric oxide donor sensitize Fas-induced apoptosis via up-regulation of Fas in human cervical cancer cells

    International Nuclear Information System (INIS)

    Park, In Chul; Woo, Sang Hyeok; Park, Myung Jin; Lee, Hyung Chahn; Lee Su Jae; Hong, Young Joon; Lee, Seung Hoon; Hong, Seok II; Rhee, Chang Hun

    2004-01-01

    Fas/CD95/Apo1 is a transmembrane receptor known to trigger apoptotic cell death in several cell types. In the present study, we showed that ionizing radiation (IR) and NO donor, S-nitroso-N-acetyl-penicillamine (SNAP), sensitized Fas-induced apoptotic cell death of HeLa human cervical cancers. Suboptimal dose of IR and SNAP up-regulated cell-surface Fas antigen, detected by FACScan using FITC-anti-Fas antibody. When combined with IR or SNAP, agonistic anti-Fas antibody CH-11 resulted in marked enhancement of apoptosis. This sensitization was completely abrogated by anti-Fas neutralizing antibody ZB4. During the IR and SNAP sensitized Fas-induced apoptosis, mitochondria permeabilization, cytochrome c release, and DNA fragmentation were detected. Furthermore, combined treatment of IR and SNAP additively up-regulated the surface Fas protein expression and sensitized Fas-induced apoptosis. Our finding demonstrate that sensitization of HeLa cervical cells to Fas-mediated apoptosis by IR and NO donor is most likely due to the up-regulation of Fas expression and also provides a means with which to sensitize tumors to the killing effects of cancer therapy via the Fas receptor

  1. 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

    2016-11-01

    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

  2. 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.

  3. 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 ...

  4. Formation of stable small cell number three-dimensional ovarian cancer spheroids using hanging drop arrays for preclinical drug sensitivity assays.

    Science.gov (United States)

    Raghavan, Shreya; Ward, Maria R; Rowley, Katelyn R; Wold, Rachel M; Takayama, Shuichi; Buckanovich, Ronald J; Mehta, Geeta

    2015-07-01

    Ovarian cancer grows and metastasizes from multicellular spheroidal aggregates within the ascites fluid. Multicellular tumor spheroids are therefore physiologically significant 3D in vitro models for ovarian cancer research. Conventional hanging drop cultures require high starting cell numbers, and are tedious for long-term maintenance. In this study, we generate stable, uniform multicellular spheroids using very small number of ovarian cancer cells in a novel 384 well hanging drop array platform. We used novel tumor spheroid platform and two ovarian cancer cell lines (A2780 and OVCAR3) to demonstrate the stable incorporation of as few as 10 cells into a single spheroid. Spheroids had uniform geometry, with projected areas (42.60×10(3)μm-475.22×10(3)μm(2) for A2780 spheroids and 37.24×10(3)μm(2)-281.01×10(3)μm(2) for OVCAR3 spheroids) that varied as a function of the initial cell seeding density. Phalloidin and nuclear stains indicated cells formed tightly packed spheroids with demarcated boundaries and cell-cell interaction within spheroids. Cells within spheroids demonstrated over 85% viability. 3D tumor spheroids demonstrated greater resistance (70-80% viability) to cisplatin chemotherapy compared to 2D cultures (30-50% viability). Ovarian cancer spheroids can be generated from limited cell numbers in high throughput 384 well plates with high viability. Spheroids demonstrate therapeutic resistance relative to cells in traditional 2D culture. Stable incorporation of low cell numbers is advantageous when translating this research to rare patient-derived cells. This system can be used to understand ovarian cancer spheroid biology, as well as carry out preclinical drug sensitivity assays. Copyright © 2015 Elsevier Inc. All rights reserved.

  5. Rapid and sensitive phenotypic marker detection on breast cancer cells using surface-enhanced Raman scattering (SERS) imaging.

    Science.gov (United States)

    Lee, Sangyeop; Chon, Hyangah; Lee, Jiyoung; Ko, Juhui; Chung, Bong Hyun; Lim, Dong Woo; Choo, Jaebum

    2014-01-15

    We report a surface-enhanced Raman scattering (SERS)-based cellular imaging technique to detect and quantify breast cancer phenotypic markers expressed on cell surfaces. This technique involves the synthesis of SERS nano tags consisting of silica-encapsulated hollow gold nanospheres (SEHGNs) conjugated with specific antibodies. Hollow gold nanospheres (HGNs) enhance SERS signal intensity of individual particles by localizing surface electromagnetic fields through pinholes in the hollow particle structures. This capacity to enhance imaging at the level of single molecules permits the use of HGNs to detect specific biological markers expressed in living cancer cells. In addition, silica encapsulation greatly enhances the stability of nanoparticles. Here we applied a SERS-based imaging technique using SEHGNs in the multiplex imaging of three breast cancer cell phenotypes. Expression of epidermal growth factor (EGF), ErbB2, and insulin-like growth factor-1 (IGF-1) receptors were assessed in the MDA-MB-468, KPL4 and SK-BR-3 human breast cancer cell lines. SERS imaging technology described here can be used to test the phenotype of a cancer cell and quantify proteins expressed on the cell surface simultaneously. Based on results, this technique may enable an earlier diagnosis of breast cancer than is currently possible and offer guidance in treatment. © 2013 Elsevier B.V. All rights reserved.

  6. Fentanyl induces autophagy via activation of the ROS/MAPK pathway and reduces the sensitivity of cisplatin in lung cancer cells.

    Science.gov (United States)

    Yao, Jiaqi; Ma, Chi; Gao, Wei; Liang, Jinxiao; Liu, Chang; Yang, Hongfang; Yan, Qiu; Wen, Qingping

    2016-12-01

    Cancer pain is the most common complication of lung carcinoma. Opioid agonist fentanyl is widely used for relieving pain in cancer patients, and cisplatin (DDP)‑based chemotherapy is commonly used for the treatment of advanced lung cancer; these two drugs are always used together in lung carcinoma patients. However, the mechanisms and related biological pathways by which fentanyl influences cisplatin sensitivity are relatively poorly reported. Here, we found that fentanyl reduces the sensitivity of cisplatin in human lung cancer cells and induces autophagy. Fentanyl induced reactive oxygen species (ROS) generation and JNK activation. N-acetyl‑L‑cysteine is a ROS scavenger and antioxidant, and the inhibition of JNK with SP600125 prevented fentanyl‑induced autophagy. We also found that 3-methyladenine (3-MA; an autophagy inhibitor) increased the sensitivity of DDP and weakened the inhibition of fentanyl. In conclusion, fentanyl reduces the sensitivity of cisplatin in lung cancer cells through the ROS-JNK-autophagy pathway, whereas the autophagy inhibitor 3-MA may weaken this effect.

  7. 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.

  8. Glutamine deficiency induces DNA alkylation damage and sensitizes cancer cells to alkylating agents through inhibition of ALKBH enzymes.

    Science.gov (United States)

    Tran, Thai Q; Ishak Gabra, Mari B; Lowman, Xazmin H; Yang, Ying; Reid, Michael A; Pan, Min; O'Connor, Timothy R; Kong, Mei

    2017-11-01

    Driven by oncogenic signaling, glutamine addiction exhibited by cancer cells often leads to severe glutamine depletion in solid tumors. Despite this nutritional environment that tumor cells often experience, the effect of glutamine deficiency on cellular responses to DNA damage and chemotherapeutic treatment remains unclear. Here, we show that glutamine deficiency, through the reduction of alpha-ketoglutarate, inhibits the AlkB homolog (ALKBH) enzymes activity and induces DNA alkylation damage. As a result, glutamine deprivation or glutaminase inhibitor treatment triggers DNA damage accumulation independent of cell death. In addition, low glutamine-induced DNA damage is abolished in ALKBH deficient cells. Importantly, we show that glutaminase inhibitors, 6-Diazo-5-oxo-L-norleucine (DON) or CB-839, hypersensitize cancer cells to alkylating agents both in vitro and in vivo. Together, the crosstalk between glutamine metabolism and the DNA repair pathway identified in this study highlights a potential role of metabolic stress in genomic instability and therapeutic response in cancer.

  9. Simultaneous gene silencing of Bcl-2, XIAP and Survivin re-sensitizes pancreatic cancer cells towards apoptosis

    International Nuclear Information System (INIS)

    Rückert, Felix; Samm, Nicole; Lehner, Anne-Kathrin; Saeger, Hans-Detlev; Grützmann, Robert; Pilarsky, Christian

    2010-01-01

    Pancreatic ductal adenocarcinoma shows a distinct apoptosis resistance, which contributes significantly to the aggressive nature of this tumor and constrains the effectiveness of new therapeutic strategies. Apoptosis resistance is determined by the net balance of the cells pro-and anti-apoptotic 'control mechanisms'. Numerous dysregulated anti-apoptotic genes have been identified in pancreatic cancer and seem to contribute to the high anti-apoptotic buffering capacity. We aimed to compare the benefit of simultaneous gene silencing (SGS) of several candidate genes with conventional gene silencing of single genes. From literature search we identified the anti-apoptotic genes XIAP, Survivin and Bcl-2 as commonly upregulated in pancreatic cancer. We performed SGS and silencing of single candidate genes using siRNA molecules in two pancreatic cancer cell lines. Effectiveness of SGS was assessed by qRT-PCR and western blotting. Apoptosis induction was measured by flow cytometry and caspase activation. Simultaneous gene silencing reduced expression of the three target genes effectively. Compared to silencing of a single target or control, SGS of these genes resulted in a significant higher induction of apoptosis in pancreatic cancer cells. In the present study we performed a subliminal silencing of different anti-apoptotic target genes simultaneously. Compared to silencing of single target genes, SGS had a significant higher impact on apoptosis induction in pancreatic cancer cells. Thereby, we give further evidence for the concept of an anti-apoptotic buffering capacity of pancreatic cancer cells

  10. Rapid and Sensitive Detection of Breast Cancer Cells in Patient Blood with Nuclease-Activated Probe Technology

    Directory of Open Access Journals (Sweden)

    Sven Kruspe

    2017-09-01

    Full Text Available A challenge for circulating tumor cell (CTC-based diagnostics is the development of simple and inexpensive methods that reliably detect the diverse cells that make up CTCs. CTC-derived nucleases are one category of proteins that could be exploited to meet this challenge. Advantages of nucleases as CTC biomarkers include: (1 their elevated expression in many cancer cells, including cells implicated in metastasis that have undergone epithelial-to-mesenchymal transition; and (2 their enzymatic activity, which can be exploited for signal amplification in detection methods. Here, we describe a diagnostic assay based on quenched fluorescent nucleic acid probes that detect breast cancer CTCs via their nuclease activity. This assay exhibited robust performance in distinguishing breast cancer patients from healthy controls, and it is rapid, inexpensive, and easy to implement in most clinical labs. Given its broad applicability, this technology has the potential to have a substantive impact on the diagnosis and treatment of many cancers. Keywords: cancer, circulating tumor cells, diagnostic nucleic acids, nucleases, diagnostic markers, breast cancer, liquid biopsy

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

    International Nuclear Information System (INIS)

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

    2014-01-01

    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. (paper)

  12. Novel Mad2-targeting miR-493-3p controls mitotic fidelity and cancer cells' sensitivity to paclitaxel.

    Science.gov (United States)

    Tambe, Mahesh; Pruikkonen, Sofia; Mäki-Jouppila, Jenni; Chen, Ping; Elgaaen, Bente Vilming; Straume, Anne Hege; Huhtinen, Kaisa; Cárpen, Olli; Lønning, Per Eystein; Davidson, Ben; Hautaniemi, Sampsa; Kallio, Marko J

    2016-03-15

    The molecular pathways that contribute to the proliferation and drug response of cancer cells are highly complex and currently insufficiently characterized. We have identified a previously unknown microRNA-based mechanism that provides cancer cells means to stimulate tumorigenesis via increased genomic instability and, at the same time, evade the action of clinically utilized microtubule drugs. We demonstrate miR-493-3p to be a novel negative regulator of mitotic arrest deficient-2 (MAD2), an essential component of the spindle assembly checkpoint that monitors the fidelity of chromosome segregation. The microRNA targets the 3' UTR of Mad2 mRNA thereby preventing translation of the Mad2 protein. In cancer cells, overexpression of miR-493-3p induced a premature mitotic exit that led to increased frequency of aneuploidy and cellular senescence in the progeny cells. Importantly, excess of the miR-493-3p conferred resistance of cancer cells to microtubule drugs. In human neoplasms, miR-493-3p and Mad2 expression alterations correlated with advanced ovarian cancer forms and high miR-493-3p levels were associated with reduced survival of ovarian and breast cancer patients with aggressive tumors, especially in the paclitaxel therapy arm. Our results suggest that intratumoral profiling of miR-493-3p and Mad2 levels can have diagnostic value in predicting the efficacy of taxane chemotherapy.

  13. NF-κB targeting by way of IKK inhibition sensitizes lung cancer cells to adenovirus delivery of TRAIL

    Directory of Open Access Journals (Sweden)

    Karacay Bahri

    2010-10-01

    Full Text Available Abstract Background Lung cancer causes the highest rate of cancer-related deaths both in men and women. As many current treatment modalities are inadequate in increasing patient survival, new therapeutic strategies are required. TNF-related apoptosis-inducing ligand (TRAIL selectively induces apoptosis in tumor cells but not in normal cells, prompting its current evaluation in a number of clinical trials. The successful therapeutic employment of TRAIL is restricted by the fact that many tumor cells are resistant to TRAIL. The goal of the present study was to test a novel combinatorial gene therapy modality involving adenoviral delivery of TRAIL (Ad5hTRAIL and IKK inhibition (AdIKKβKA to overcome TRAIL resistance in lung cancer cells. Methods Fluorescent microscopy and flow cytometry were used to detect optimum doses of adenovirus vectors to transduce lung cancer cells. Cell viability was assessed via a live/dead cell viability assay. Luciferase assays were employed to monitor cellular NF-κB activity. Apoptosis was confirmed using Annexin V binding. Results Neither Ad5hTRAIL nor AdIKKβKA infection alone induced apoptosis in A549 lung cancer cells, but the combined use of Ad5hTRAIL and AdIKKβKA significantly increased the amount of A549 apoptosis. Luciferase assays demonstrated that both endogenous and TRAIL-induced NF-κB activity was down-regulated by AdIKKβKA expression. Conclusions Combination treatment with Ad5hTRAIL and AdIKKβKA induced significant apoptosis of TRAIL-resistant A549 cells, suggesting that dual gene therapy strategy involving exogenous TRAIL gene expression with concurrent IKK inhibition may be a promising novel gene therapy modality to treat lung cancer.

  14. NF-κB targeting by way of IKK inhibition sensitizes lung cancer cells to adenovirus delivery of TRAIL

    International Nuclear Information System (INIS)

    Aydin, Cigdem; Sanlioglu, Ahter D; Bisgin, Atil; Yoldas, Burcak; Dertsiz, Levent; Karacay, Bahri; Griffith, Thomas S; Sanlioglu, Salih

    2010-01-01

    Lung cancer causes the highest rate of cancer-related deaths both in men and women. As many current treatment modalities are inadequate in increasing patient survival, new therapeutic strategies are required. TNF-related apoptosis-inducing ligand (TRAIL) selectively induces apoptosis in tumor cells but not in normal cells, prompting its current evaluation in a number of clinical trials. The successful therapeutic employment of TRAIL is restricted by the fact that many tumor cells are resistant to TRAIL. The goal of the present study was to test a novel combinatorial gene therapy modality involving adenoviral delivery of TRAIL (Ad5hTRAIL) and IKK inhibition (AdIKKβKA) to overcome TRAIL resistance in lung cancer cells. Fluorescent microscopy and flow cytometry were used to detect optimum doses of adenovirus vectors to transduce lung cancer cells. Cell viability was assessed via a live/dead cell viability assay. Luciferase assays were employed to monitor cellular NF-κB activity. Apoptosis was confirmed using Annexin V binding. Neither Ad5hTRAIL nor AdIKKβKA infection alone induced apoptosis in A549 lung cancer cells, but the combined use of Ad5hTRAIL and AdIKKβKA significantly increased the amount of A549 apoptosis. Luciferase assays demonstrated that both endogenous and TRAIL-induced NF-κB activity was down-regulated by AdIKKβKA expression. Combination treatment with Ad5hTRAIL and AdIKKβKA induced significant apoptosis of TRAIL-resistant A549 cells, suggesting that dual gene therapy strategy involving exogenous TRAIL gene expression with concurrent IKK inhibition may be a promising novel gene therapy modality to treat lung cancer

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

    Science.gov (United States)

    2013-08-01

    Janelia Farm , VA, travel award 2010 -­‐ Translational Medicine Symposium, HHMI Peer Cluster Meeting, travel award 2010 -­‐ AACR Annual Conference...lab. Science Education Alliance, Janelia Farm , VA, 2001 3. Londoño-Joshi AI, Forero-Torres A, Fineberg NS, Oliver PG, Zhou T, LoBuglio AF, Buchsbaum...rabbit mAb and cleaved caspase 3 rabbit mAb were purchased from Cell Signaling (Billerica, MA). Secondary antibodies, Alexa fluor 405 goat anti-rabbit

  16. 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.

  17. Indomethacin sensitive suppressor cell activity in head and neck cancer patients pre- and postirradiation therapy

    International Nuclear Information System (INIS)

    Maca, R.D.; Panje, W.R.

    1982-01-01

    The effects of the addition of indomethacin to PHA or Con A stimulated lymphocytes from patients with untreated squamous cell carcinoma of the head and neck or from patients with the disease who have just finished irradiation therapy from the disease was quantitated and compared to those of the control group. Lymphocytes from eight of 26 patients with untreated carcinoma were significantly augmented by the addition of indomethacin. The remaining eighteen patients were equal to the controls. For all 17 patients who had just finished extensive field irradiation therapy, significant enhancement of PHA and Con A reactivity by indomethacin was found, which did not appear to be solely a function of low baseline mitogen reactivity. The results of this study support the hypothesis that perhaps patients receiving irradiation therapy may benefit by the oral administration of indomethacin, an approach that needs further consideration

  18. 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.

  19. MicroRNA-101 inhibits cell proliferation, promotes cell apoptosis and increases sensitivity of breast cancer MDA-MB-231 cells to paclitaxel

    Directory of Open Access Journals (Sweden)

    Qiu-Lin Ke

    2016-02-01

    Full Text Available Objective: To explore the effect that miR-101 inhibits breast cancer MDA-MB-231 cell proliferation and increases the chemosensitivity of paclitaxel to breast cancer MDA-MB-231 cells and its influence on protein expression level of target gene Bcl2. Methods: miR-101 was artificially synthesized, it used liposome 3000 to transfect MDA-MB-231 cells, and experiment was divided into three groups: blank control group, negative control group and miR-101 group. MTT assay was used to detect the effect of miR-101 on MDA-MB-231 cell proliferation and chemosensitivity of paclitaxel-mediated MDA-MB-231 cells; flow cytometer was used to detect cell apoptosis. Real-time PCR and Western bloting were used to detect the changes of mRNA and protein expression levels of Bcl2. Results: After miR-101 transfected MDA-MB- 231 cells, cell proliferation ability significantly decreased compared with negative control group, and differences had statistical significance (P<0.01; after paclitaxel was used to process cells, IC50 of miR-101-processing group decreased by 2.45 times compared with blank control group, differences had statistical significance (P<0.05 and differences between blank control group and negative control group had no statistical significance; detection results by flow cytometer showed that both early-stage and late-stage apoptosis rates of MDA-MB-231 cells of miR-101 group were significantly higher than those of negative control group (P<0.05, and early-stage apoptosis rate was more significant (P<0.01; after transfection of miR-101, mRNA and protein levels of Bcl2 of MDA-MB-231 cells significantly decreased, and differences had statistical significance (P<0.05. Conclusion: miR-101 can inhibit breast cancer MDAMB- 231 cell proliferation through targeting and downregulating Bcl2, thereby increasing the chemosensitivity of breast cancer cells to paclitaxel and promoting cell apoptosis.

  20. Proteomic Profiling Reveals That Resveratrol Inhibits HSP27 Expression and Sensitizes Breast Cancer Cells to Doxorubicin Therapy

    OpenAIRE

    D?az-Ch?vez, Jos?; Fonseca-S?nchez, Miguel A.; Arechaga-Ocampo, Elena; Flores-P?rez, Ali; Palacios-Rodr?guez, Yadira; Dom?nguez-G?mez, Guadalupe; Marchat, Laurence A.; Fuentes-Mera, Lizeth; Mendoza-Hern?ndez, Guillermo; Gariglio, Patricio; L?pez-Camarillo, C?sar

    2013-01-01

    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 s...

  1. 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.

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

    International Nuclear Information System (INIS)

    Kim, In Gyu; Kim, Seo Yoen; Kim, Hyun A; Kim, Jeong Yul; Lee, Jae Ha; Choi, Soo Im; Han, Jeong Ran; Kim, Kug Chan; Cho, Eun Wie

    2014-01-01

    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

  3. The presence of a membrane-bound progesterone receptor sensitizes the estradiol-induced effect on the proliferation of human breast cancer cells.

    Science.gov (United States)

    Neubauer, Hans; Yang, Yang; Seeger, Harald; Fehm, Tanja; Cahill, Michael A; Tong, Xiaowen; Ruan, Xiangyan; Mueck, Alfred O

    2011-08-01

    Breast cancer risk is still an important topic regarding hormone therapy as well as oral contraception. Evidence that progestogens may play a crucial role is accumulating. Progesterone receptor membrane component 1 (PGRMC1) expressed in breast cancer may be important in tumorigenesis and thus may increase breast cancer risk. The aim of this project was to investigate the influence of different estradiol (E2) concentrations and the addition of two progestogens on MCF-7 breast cancer cells overexpressing PGRMC1. MCF-7 cells were stably transfected with PGRMC1 expression plasmid (MCF-7/PGRMC1-3HA [WT-12]). To test the effects of E2 and progestogens on cell proliferation, MCF-7 and WT-12 cells were stimulated with different concentrations of E2 (10 and 10 M) alone and in combination with progesterone and medroxyprogesterone acetate (each 10 M). E2 elicited a concentration-dependent proliferative effect on both cell lines, which was much more pronounced in WT-12 cells (50% vs 200%). This effect could be completely abrogated by the addition of the E2 antagonist fulvestrant. Addition of progesterone had no influence on the E2-induced effect, whereas medroxy-progesterone acetate enhanced the E2-induced effect at a low E2 concentration, which was, again, more pronounced in the WT-12 cells. The figures were between 20% and 40% in MCF-7 and between 60% and 250% in WT-12 cells. Overexpression of PGRMC1 sensitizes the proliferative response of the MCF-7 breast cancer cell line to estradiol. The effect of progestogens on breast cancer tumorigenesis may depend on the specific progestogen used for hormone therapy or oral contraception.

  4. Hypoxic-cell sensitizers

    International Nuclear Information System (INIS)

    Dische, S.

    1983-01-01

    There is now 6 years of clinical experience with misonidazole as a hypoxic-cell sensitizer. Neurotoxicity limits the total dose which may be given, and so relatively low concentrations of radiosensitizing drugs are likely to be achieved in hypoxic cells in man as compared with those in animal tumors. It is likely that benefit will only be shown in those situations where radioresistant hypoxic cells strongly dominate as a cause of radiation failure. Many clinical trials are underway, and thus far some show no benefit while in others there is a definite advantage to the patients given the drug. These trials must be continued to their conclusion, but misonidazole must be regarded as the first of a series of radiosensitizers to reach the clinic for trial. There is a promise of more effective drugs becoming available within the next few years. Those showing a lower lipophilicity than misonidazole have been found to have a shorter half-life and a lower uptake in neural tissue in animal studies. One such drug, desmethylmisonidazole, is presently undergoing clinical trial

  5. TAS-116, a novel Hsp90 inhibitor, selectively enhances radio-sensitivity of human cancer cells to X-rays and carbon ion radiation

    Science.gov (United States)

    Lee, Younghyun; Sunada, Shigeaki; Hirakawa, Hirokazu; Fujimori, Akira; Nickoloff, Jac A.; Okayasu, Ryuichi

    2016-01-01

    Hsp90 inhibitors have been investigated as cancer therapeutics in mono-therapy and to augment radiotherapy, however serious adverse effects of early generation Hsp90 inhibitors limited their development. TAS-116 is a novel Hsp90 inhibitor with lower adverse effects than other Hsp90 inhibitors, and here we investigated the radio-sensitizing effects of TAS-116 in low LET X-ray, and high LET carbon ion irradiated human cancer cells and mouse tumor xenografts. TAS-116 decreased cell survival of both X-ray and carbon ion-irradiated human cancer cell lines (HeLa and H1299 cells), and similar to other Hsp90 inhibitors, it did not affect radiosensitivity of non-cancerous human fibroblasts. TAS-116 increased the number of radiation-induced γ-H2AX foci, and delayed the repair of DNA double-strand breaks (DSBs). TAS-116 reduced the expression of proteins that mediate repair of DSBs by homologous recombination (RAD51) and non-homologous end joining (Ku, DNA-PKcs), and suppressed formation of RAD51 foci and phosphorylation/activation of DNA-PKcs. TAS-116 also decreased expression of the cdc25 cell cycle progression marker, markedly increasing G2/M arrest. Combined treatment of mouse tumor xenografts with carbon ions and TAS-116 showed promising delay in tumor growth compared to either individual treatment. These results demonstrate that TAS-116 radio-sensitizes human cancer cells to both X rays and carbon ions by inhibiting the two major DSB repair pathways, and these effects were accompanied by marked cell cycle arrest. The promising results of combination TAS-116 + carbon ion radiation therapy of tumor xenografts justify further exploration of TAS-116 as an adjunct to radiotherapy using low or high LET radiation. PMID:28062703

  6. 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

    2015-01-01

    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. PMID:26416354

  7. Cytotoxicity of 18 Cameroonian medicinal plants against drug sensitive and multi-factorial drug resistant cancer cells.

    Science.gov (United States)

    Mbaveng, Armelle T; Manekeng, Hermione T; Nguenang, Gaelle S; Dzotam, Joachim K; Kuete, Victor; Efferth, Thomas

    2018-08-10

    Recommendations have been made stating that ethnopharmacological usages such as immune and skin disorders, inflammatory, infectious, parasitic and viral diseases should be taken into account if selecting plants for anticancer screening, since these reflect disease states bearing relevance to cancer or cancer-like symptoms. Cameroonian medicinal plants investigated in this work are traditionally used to treat cancer or ailments with relevance to cancer or cancer-like symptoms. In this study, 21 methanol extracts from 18 Cameroonian medicinal plants were tested in leukemia CCRF-CEM cells, and the best extracts were further tested on a panel of human cancer cell lines, including various multi-drug-resistant (MDR) phenotypes. Mechanistic studies were performed with the three best extracts. Resazurin reduction assay was used to evaluate cytotoxicity and ferroptotic effects of methanol extracts from different plants. Flow cytometry was used to analyze cell cycle, apoptosis, mitochondrial membrane potential (MMP), and reactive oxygen species (ROS) of extracts from Curcuma longa rhizomes (CLR), Lycopersicon esculentum leaves (LEL), and Psidium guajava bark (PGB). In a pre-screening of all extracts, 13 out of 21 (61.9%) had IC 50 values below 80 µg/mL. Six of these active extracts displayed IC 50 values below 30 µg/mL: Cola pachycarpa leaves (CPL), Curcuma longa rhizomes (CLR), Lycopersicon esculentum leaves, Persea americana bark (PAB), Physalis peruviana twigs (PPT) and Psidium guajava bark (PGB). The best extracts displayed IC 50 values from 6.25 µg/mL (against HCT116 p53 -/- ) to 10.29 µg/mL (towards breast adenocarcinoma MDA-MB-231-BCRP cells) for CLR, from 9.64 µg/mL (against breast adenocarcinoma MDA-MB-231 cells) to 57.74 µg/mL (against HepG2 cells) for LEL and from 1.29 µg/mL (towards CEM/ADR5000 cells) to 62.64 µg/mL (towards MDA-MB-231 cells) for PGB. CLR and PGB induced apoptosis in CCRF-CEM cells via caspases activation, MMP depletion

  8. Squamous cell cancer (image)

    Science.gov (United States)

    Squamous cell cancer involves cancerous changes to the cells of the middle portion of the epidermal skin layer. It is ... malignant tumor, and is more aggressive than basal cell cancer, but still may be relatively slow-growing. It ...

  9. Targeting pro-apoptotic trail receptors sensitizes HeLa cervical cancer cells to irradiation-induced apoptosis

    NARCIS (Netherlands)

    Maduro, John H.; de Vries, Elisabeth G. E.; Meersma, Gert-Jan; Hougardy, Brigitte M. T.; van der Zee, Ate G. J.; De Jong, Steven

    2008-01-01

    Purpose: To investigate the potential of irradiation in combination with drugs targeting the tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) death receptor (DR)4 and DR5 and their mechanism of action in a cervical cancer cell line. Methods and Materials: Recombinant human TRAIL

  10. 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

    , the compound is now also recognized as a multitargeting drug with diverse potential applications, for example, it has antiproliferative properties and it can reverse resistance toward antibiotics in bacteria. Furthermore, chlorpromazine can reverse multidrug resistance caused by overexpression of P......Tamoxifen resistance is a major clinical problem in the treatment of estrogen receptor a-positive breast tumors. It is, at present, unclear what exactly causes tamoxifen resistance. For decades, chlorpromazine has been used for treating psychotic diseases, such as schizophrenia. However......-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...

  11. 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 ...

  12. A Smac-mimetic sensitizes prostate cancer cells to TRAIL-induced apoptosis via modulating both IAPs and NF-kappaB

    International Nuclear Information System (INIS)

    Dai, Yao; Liu, Meilan; Tang, Wenhua; Li, Yongming; Lian, Jiqin; Lawrence, Theodore S; Xu, Liang

    2009-01-01

    Although tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a promising agent for human cancer therapy, prostate cancer still remains resistant to TRAIL. Both X-linked inhibitor of apoptosis (XIAP) and nuclear factor-kappaB function as key negative regulators of TRAIL signaling. In this study, we evaluated the effect of SH122, a small molecule mimetic of the second mitochondria-derived activator of caspases (Smac), on TRAIL-induced apoptosis in prostate cancer cells. The potential of Smac-mimetics to bind XIAP or cIAP-1 was examined by pull-down assay. Cytotoxicity of TRAIL and/or Smac-mimetics was determined by a standard cell growth assay. Silencing of XIAP or cIAP-1 was achieved by transient transfection of short hairpin RNA. Apoptosis was detected by Annexin V-PI staining followed by flow cytometry and by Western Blot analysis of caspases, PARP and Bid. NF-kappaB activation was determined by subcellular fractionation, real time RT-PCR and reporter assay. SH122, but not its inactive analog, binds to XIAP and cIAP-1. SH122 significantly sensitized prostate cancer cells to TRAIL-mediated cell death. Moreover, SH122 enhanced TRAIL-induced apoptosis via both the death receptor and the mitochondrial pathway. Knockdown of both XIAP and cIAP-1 sensitized cellular response to TRAIL. XIAP-knockdown attenuated sensitivity of SH122 to TRAIL-induced cytotoxicity, confirming that XIAP is an important target for IAP-inhibitor-mediated TRAIL sensitization. SH122 also suppressed TRAIL-induced NF-kappaB activation by preventing cytosolic IkappaB-alpha degradation and RelA nuclear translocation, as well as by suppressing NF-kappaB target gene expression. These results demonstrate that SH122 sensitizes human prostate cancer cells to TRAIL-induced apoptosis by mimicking Smac and blocking both IAPs and NF-kappaB. Modulating IAPs may represent a promising approach to overcoming TRAIL-resistance in human prostate cancer with constitutively active NF-kappaB signaling

  13. Sensitization of TNF-induced cytotoxicity in lung cancer cells by concurrent suppression of the NF-κB and Akt pathways

    International Nuclear Information System (INIS)

    Wang Xia; Chen Wenshu; Lin Yong

    2007-01-01

    Blockage of either nuclear factor-κB (NF-κB) or Akt sensitizes cancer cells to TNF-induced apoptosis. In this study, we investigated the undetermined effect of concurrent blockage of these two survival pathways on TNF-induced cytotoxicity in lung cancer cells. The results show that Akt contributes to TNF-induced NF-κB activation in lung cancer cells through regulating phosphorylation of the p65/RelA subunit of NF-κB. Although individually blocking IKK or Akt partially suppressed TNF-induced NF-κB activation, concurrent suppression of these pathways completely inhibited TNF-induced NF-κB activation and downstream anti-apoptotic gene expression, and synergistically potentiated TNF-induced cytotoxicity. Moreover, suppression of Akt inhibited the Akt-mediated anti-apoptotic pathway through dephosphorylation of BAD. These results indicate that concurrent suppression of NF-κB and Akt synergistically sensitizes TNF-induced cytotoxicity through blockage of distinct survival pathways downstream of NF-κB and Akt, which may be applied in lung cancer therapy

  14. Suppression of microRNA-629 enhances sensitivity of cervical cancer cells to 1'S-1'-acetoxychavicol acetate via regulating RSU1.

    Science.gov (United States)

    Phuah, Neoh Hun; Azmi, Mohamad Nurul; Awang, Khalijah; Nagoor, Noor Hasima

    2017-01-01

    Cervical cancer is the fourth most frequent malignancy affecting women worldwide, but drug resistance and toxicities remain a major challenge in chemotherapy. The use of natural compounds is promising because they are less toxic and able to target multiple signaling pathways. The 1'S-1'-acetoxychavicol acetate (ACA), a natural compound isolated from wild ginger Alpinia conchigera , induced cytotoxicity on various cancer cells including cervical cancer. MicroRNAs (miRNAs) are short noncoding RNAs that regulate numerous biological processes, such as apoptosis and chemosensitivity. Past studies reported that miR-629 is upregulated in many cancers, and its expression was altered in ACA-treated cervical cancer cells. However, the role of miR-629 in regulating sensitivity toward ACA or other anticancer agents has not been reported. Hence, this study aims to investigate the role of miR-629 in regulating response toward ACA on cervical cancer cells. The miR-629 expression following transfection with miR-629 hairpin inhibitor and hairpin inhibitor negative control was measured using quantitative real-time polymerase chain reaction (RT-qPCR). The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to investigate sensitivity toward ACA. Apoptosis was detected using Annexin V/propidium iodide and Caspase 3/7 assays. The gene target for miR-629 was identified using miRNA target prediction programs, luciferase reporter assay and Western blots. Gene overexpression studies were performed to evaluate its role in regulating response toward ACA. Transfection with miR-629 hairpin inhibitor downregulated its expression in both cervical cancer cell lines. Suppression of miR-629 increased sensitivity toward ACA by reducing cell proliferation and inducing apoptosis. Luciferase reporter assay confirmed RSU1 as a direct target of miR-629. Overexpression of miR-629 decreased RSU1 protein expression, while inhibition of miR-629 increased RSU1 protein expression

  15. Glutamine deficiency induces DNA alkylation damage and sensitizes cancer cells to alkylating agents through inhibition of ALKBH enzymes.

    Directory of Open Access Journals (Sweden)

    Thai Q Tran

    2017-11-01

    Full Text Available Driven by oncogenic signaling, glutamine addiction exhibited by cancer cells often leads to severe glutamine depletion in solid tumors. Despite this nutritional environment that tumor cells often experience, the effect of glutamine deficiency on cellular responses to DNA damage and chemotherapeutic treatment remains unclear. Here, we show that glutamine deficiency, through the reduction of alpha-ketoglutarate, inhibits the AlkB homolog (ALKBH enzymes activity and induces DNA alkylation damage. As a result, glutamine deprivation or glutaminase inhibitor treatment triggers DNA damage accumulation independent of cell death. In addition, low glutamine-induced DNA damage is abolished in ALKBH deficient cells. Importantly, we show that glutaminase inhibitors, 6-Diazo-5-oxo-L-norleucine (DON or CB-839, hypersensitize cancer cells to alkylating agents both in vitro and in vivo. Together, the crosstalk between glutamine metabolism and the DNA repair pathway identified in this study highlights a potential role of metabolic stress in genomic instability and therapeutic response in cancer.

  16. Snail-induced epithelial-to-mesenchymal transition of MCF-7 breast cancer cells: systems analysis of molecular changes and their effect on radiation and drug sensitivity

    International Nuclear Information System (INIS)

    Mezencev, Roman; Matyunina, Lilya V.; Jabbari, Neda; McDonald, John F.

    2016-01-01

    Epithelial-to-mesenchymal transition (EMT) has been associated with the acquisition of metastatic potential and the resistance of cancer cells to therapeutic treatments. MCF-7 breast cancer cells engineered to constitutively express the zinc-finger transcriptional repressor gene Snail (MCF-7-Snail cells) have been previously shown to display morphological and molecular changes characteristic of EMT. We report here the results of a comprehensive systems level molecular analysis of changes in global patterns of gene expression and levels of glutathione and reactive oxygen species (ROS) in MCF-7-Snail cells and the consequence of these changes on the sensitivity of cells to radiation treatment and therapeutic drugs. Snail-induced changes in global patterns of gene expression were identified by microarray profiling using the Affymetrix platform (U133 Plus 2.0). The resulting data were processed and analyzed by a variety of system level analytical methods. Levels of ROS and glutathione (GSH) were determined by fluorescent and luminescence assays, and nuclear levels of NF-κB protein were determined by an ELISA based method. The sensitivity of cells to ionizing radiation and anticancer drugs was determined using a resazurin-based cell cytotoxicity assay. Constitutive ectopic expression of Snail in epithelial-like, luminal A-type MCF-7 cells induced significant changes in the expression of >7600 genes including gene and miRNA regulators of EMT. Mesenchymal-like MCF-7-Snail cells acquired molecular profiles characteristic of triple-negative, claudin-low breast cancer cells, and displayed increased sensitivity to radiation treatment, and increased, decreased or no change in sensitivity to a variety of anticancer drugs. Elevated ROS levels in MCF-7-Snail cells were unexpectedly not positively correlated with NF-κB activity. Ectopic expression of Snail in MCF-7 cells resulted in morphological and molecular changes previously associated with EMT. The results underscore the

  17. 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.

  18. Mucuna pruriens (L.) DC chemo sensitize human breast cancer cells via downregulation of prolactin-mediated JAK2/STAT5A signaling.

    Science.gov (United States)

    Sinha, Sonam; Sharma, Sonal; Vora, Jaykant; Shah, Heta; Srivastava, Anshu; Shrivastava, Neeta

    2018-05-10

    Mucuna pruriens (L.) DC (MP) is an ancient Indian medicinal plant traditionally used to treat Parkinson's disease. L-Dopa (LD), precursor of dopamine is abundantly found in the seeds of MP. L-dopa is a natural inhibitor of prolactin (PRL) hormone which is required to maintain lactation in women but it's over production (hyperprolactinemia) plays critical role in advancement of breast cancer. We aim to examine the pharmacological effect of LD and MP on this hyperprolactinemia associated breast cancer and related signaling for effective management of the disease. We also investigated chemo-sensitizing effect of MP on hyperprolactinemia-mediated cisplatin resistance. Methanolic seed extract of MP were prepared and analysed using HPLC. Effect of LD and MP on the cellular viability of breast cancer cells (T47D, MCF-7, MDA-MB-468 and MDA-MB-231) were evaluated using MTT assay. Further, effect of LD and MP on colony forming potential, DNA damage, cell cycle distribution and apoptosis was determined using agar/agarose method, comet assay and annexin and PI method followed by FACS analysis. To reveal the molecular mechanism involved in the anti-cancer activity of MP, transcriptional and translational level analysis of the key proteins involved in the PRL-mediated signaling, was performed using RT-PCR and western blot analysis. The effect of MP extract on PRL-mediated signaling was validated using dopaminergic agonist bromocriptine. MP extract and cisplatin was given in different combination with appropriate controls to check their effect on chemo-resistivity of breast cancer cells. Our results demonstrated that MP seed extract has the potential to inhibit cellular proliferation of PRL expressing T47D and MCF-7 breast cancer cells via induction of DNA damage, G1 phase of cell cycle arrest and apoptosis more effectively as compare to LD. Further, MP-mediated anti-cancerous effect was associated with the downregulation of PRL expression, further suppressing the JAK2/STAT5A

  19. 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

    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...... to identify colon cancer patients who may benefit from 5-FU, however, any biomarker predicting benefit for adjuvant 5-FU must be rigorously evaluated in independent cohorts. Given differences between the two study cohorts, the present results should be further validated....

  20. Clusterin silencing sensitizes pancreatic cancer MIA-PaCa-2 cells to gmcitabine via regulation of NF-kB/Bcl-2 signaling.

    Science.gov (United States)

    Xu, Miao; Chen, Xiumei; Han, Yanling; Ma, Chunqing; Ma, Lin; Li, Shirong

    2015-01-01

    Clusterin (CLU) is known as a multifunctional protein involved in a variety of physiological processes including lipid transport, epithelial cell differentiation, tumorigenesis, and apoptosis. Our recent study has demonstrated that knockdown of clusterin sensitizes pancreatic cancer cell lines to gmcitabine treatment. However the details of this survival mechanism remain undefined. Of the various downstream targets of CLU, we examined activation of the NF-kB transcription factor and subsequent transcriptional regulation of BCL-2 gene in pancreatic cancer cell MIA-PaCa-2. The MIA-PaCa-2 cells were transfected with an antisense oligonucleotide (ASO) against clusterin, which led to a decreased protein level of the antiapoptotic gene BCL-2. Furthermore, inhibition of CLU decreased the function of NF-kB, which is capable of transcriptional regulation of the BCL-2 gene. Inhibiting this pathway increased the apoptotic effect of gmcitabine chemotherapy. Re-activated NF-kB resulted in attenuation of ASO-induced effects, followed by the bcl-2 upregulation, and bcl-2 re-inhibition resulted in attenuation of Re-activated NF-kB -induced effects. Animals injected with ASO CLU in MIA-PaCa-2 cells combined with gmcitabine treatment had fewer tumors than gmcitabine or ASO CLU alone. These findings suggest that knockdown of CLU sensitized MIA-PaCa-2 cells to gmcitabine chemotherapy through modulating NF-Kb/bcl-2 pathway.

  1. Curcumin sensitizes prostate cancer cells to radiation partly via epigenetic activation of miR-143 and miR-143 mediated autophagy inhibition.

    Science.gov (United States)

    Liu, Jianbo; Li, Min; Wang, Yuewei; Luo, Jianchao

    2017-08-01

    Curcumin has been reported as a radiosensitizer in prostate cancer. But the underlying mechanism is not well understood. In this study, we firstly assessed how curcumin affects the expression of miR-143/miR-145 cluster. Then, we investigated whether miR-143 is involved in regulation of radiosensitivity and its association with autophagy in prostate cancer cells. Our data showed that PC3, DU145 and LNCaP cells treated with curcumin had significantly restored miR-143 and miR-145 expression. Curcumin showed similar effect as 5-AZA-dC on reducing methylation of CpG dinucleotides in miR-143 promoter. In addition, curcumin treatment reduced the expression of DNMT1 and DNMT3B, which contribute to promoter hypermethylation of the miR-143/miR-145 cluster. Therefore, we infer that curcumin can restore miR-143 and miR-145 expression via hypomethylation. MiR-143 overexpression and curcumin pretreatment enhanced radiation induced cancer cell growth inhibition and apoptosis. MiR-143 and curcumin remarkably reduced radiation-induced autophagy in PC3 and DU145 cells. MiR-143 overexpression alone also reduced the basal level of autophagy in DU145 cells. Mechanistically, miR-143 can suppress autophagy in prostate cancer cells at least via downregulating ATG2B. Based on these findings, we infer that curcumin sensitizes prostate cancer cells to radiation partly via epigenetic activation of miR-143 and miR-143 mediated autophagy inhibition.

  2. Ecdysteroids Sensitize MDR and Non-MDR Cancer Cell Lines to Doxorubicin, Paclitaxel, and Vincristine but Tend to Protect Them from Cisplatin

    Directory of Open Access Journals (Sweden)

    Ana Martins

    2015-01-01

    Full Text Available Ecdysteroids, analogs of the insect molting hormone, are known for their various mild, nonhormonal bioactivities in mammals. Previously, we reported that less-polar ecdysteroids can modulate the doxorubicin resistance of a multidrug resistant (MDR mouse lymphoma cell line expressing the human ABCB1 transporter. Here, we describe the ability of 20-hydroxyecdysone (1 and its mono- (2 and diacetonide (3 derivatives to sensitize various MDR and non-MDR cancer cell lines towards doxorubicin, paclitaxel, vincristine, or cisplatin. Drug IC50 values with or without ecdysteroid were determined by MTT assay. Compound 3 significantly sensitized all cell lines to each chemotherapeutic except for cisplatin, whose activity was decreased. In order to overcome solubility and stability issues for the future in vivo administration of compound 3, liposomal formulations were developed. By means of their combination index values obtained via checkerboard microplate method, a formulation showed superior activity to that of compound 3 alone. Because ecdysteroids act also on non-ABCB1 expressing (sensitive cell lines, our results demonstrate that they do not or not exclusively exert their adjuvant anticancer activity as ABCB1 inhibitors, but other mechanisms must be involved, and they opened the way towards their in vivo bioactivity testing against various cancer xenografts.

  3. 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

    International Nuclear Information System (INIS)

    Chen, Daquan; Wang, Guohua; Song, Weiguo; Zhang, Qiang

    2015-01-01

    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

  4. 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

  5. Systemic analysis of different colorectal cancer cell lines and TCGA datasets identified IGF-1R/EGFR-PPAR-CASPASE axis as important indicator for radiotherapy sensitivity.

    Science.gov (United States)

    Chen, Lin; Zhu, Zhe; Gao, Wei; Jiang, Qixin; Yu, Jiangming; Fu, Chuangang

    2017-09-05

    Insulin-like growth factor 1 receptor (IGF-1R) is proved to contribute the development of many types of cancers. But, little is known about its roles in radio-resistance of colorectal cancer (CRC). Here, we demonstrated that low IGF-1R expression value was associated with the better radiotherapy sensitivity of CRC. Besides, through Quantitative Real-time PCR (qRT-PCR), the elevated expression value of epidermal growth factor receptor (EGFR) was observed in CRC cell lines (HT29, RKO) with high radio-sensitivity compared with those with low sensitivity (SW480, LOVO). The irradiation induced apoptosis rates of wild type and EGFR agonist (EGF) or IGF-1R inhibitor (NVP-ADW742) treated HT29 and SW480 cells were quantified by flow cytometry. As a result, the apoptosis rate of EGF and NVP-ADW742 treated HT29 cells was significantly higher than that of those wild type ones, which indicated that high EGFR and low IGF-1R expression level in CRC was associated with the high sensitivity to radiotherapy. We next conducted systemic bioinformatics analysis of genome-wide expression profiles of CRC samples from the Cancer Genome Atlas (TCGA). Differential expression analysis between IGF-1R and EGFR abnormal CRC samples, i.e. CRC samples with higher IGF-1R and lower EGFR expression levels based on their median expression values, and the rest of CRC samples identified potential genes contribute to radiotherapy sensitivity. Functional enrichment of analysis of those differential expression genes (DEGs) in the Database for Annotation, Visualization and Integrated Discovery (DAVID) indicated PPAR signaling pathway as an important pathway for the radio-resistance of CRC. Our study identified the potential biomarkers for the rational selection of radiotherapy for CRC patients. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. 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.

  7. Simultaneous targeting of ATM and Mcl-1 increases cisplatin sensitivity of cisplatin-resistant non-small cell lung cancer.

    Science.gov (United States)

    Zhang, Fuquan; Shen, Mingjing; Yang, Li; Yang, Xiaodong; Tsai, Ying; Keng, Peter C; Chen, Yongbing; Lee, Soo Ok; Chen, Yuhchyau

    2017-08-03

    Development of cisplatin-resistance is an obstacle in non-small cell lung cancer (NSCLC) therapeutics. To investigate which molecules are associated with cisplatin-resistance, we analyzed expression profiles of several DNA repair and anti-apoptosis associated molecules in parental (A549P and H157P) and cisplatin-resistant (A549CisR and H157CisR) NSCLC cells. We detected constitutively upregulated nuclear ATM and cytosolic Mcl-1 molcules in cisplatin-resistant cells compared with parental cells. Increased levels of phosphorylated ATM (p-ATM) and its downstream molecules, CHK2, p-CHK2, p-53, and p-p53 were also detected in cisplatin-resistant cells, suggesting an activation of ATM signaling in these cells. Upon inhibition of ATM and Mcl-1 expression/activity using specific inhibitors of ATM and/or Mcl-1, we found significantly enhanced cisplatin-cytotoxicity and increased apoptosis of A549CisR cells after cisplatin treatment. Several A549CisR-derived cell lines, including ATM knocked down (A549CisR-siATM), Mcl-1 knocked down (A549CisR-shMcl1), ATM/Mcl-1 double knocked down (A549CisR-siATM/shMcl1) as well as scramble control (A549CisR-sc), were then developed. Higher cisplatin-cytotoxicity and increased apoptosis were observed in A549CisR-siATM, A549CisR-shMcl1, and A549CisR-siATM/shMcl1 cells compared with A549CisR-sc cells, and the most significant effect was shown in A549CisR-siATM/shMcl1 cells. In in vivo mice studies using subcutaneous xenograft mouse models developed with A549CisR-sc and A549CisR-siATM/shMcl1 cells, significant tumor regression in A549CisR-siATM/shMcl1 cells-derived xenografts was observed after cisplatin injection, but not in A549CisR-sc cells-derived xenografts. Finally, inhibitor studies revealed activation of Erk signaling pathway was most important in upregulation of ATM and Mcl-1 molcules in cisplatin-resistant cells. These studies suggest that simultaneous blocking of ATM/Mcl-1 molcules or downstream Erk signaling may recover the

  8. 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.

  9. 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.

  10. 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.

  11. Unlocking the chromatin of adenoid cystic carcinomas using HDAC inhibitors sensitize cancer stem cells to cisplatin and induces tumor senescence

    Directory of Open Access Journals (Sweden)

    Luciana O. Almeida

    2017-05-01

    Full Text Available Adenoid cystic carcinoma (ACC is an uncommon malignancy of the salivary glands that is characterized by local recurrence and distant metastasis due to its resistance to conventional therapy. Platinum-based therapies have been extensively explored as a treatment for ACC, but they show little effectiveness. Studies have shown that a specific group of tumor cells, harboring characteristics of cancer stem cells (CSCs, are involved in chemoresistance of myeloid leukemias, breast, colorectal and pancreatic carcinomas. Therapeutic strategies that target CSCs improve the survival of patients by decreasing the rates of tumor relapse, and epigenetic drugs, such as histone deacetylase inhibitors (HDACi, have shown promising results in targeting CSCs. In this study, we investigated the effect of the HDACi Suberoylanilide hydroxamic acid (Vorinostat, and cisplatin, alone or in combination, on CSCs and non-CSCs from ACC. We used CSCs as a biological marker for tumor resistance to therapy in patient-derived xenograft (PDX samples and ACC primary cells. We found that cisplatin reduced tumor viability, but enriched the population of CSCs. Systemic administration of Vorinostat reduced the number of detectable CSCs in vivo and in vitro, and a low dose of Vorinostat decreased tumor cell viability. However, the combination of Vorinostat and cisplatin was extremely effective in depleting CSCs and reducing tumor viability in all ACC primary cells by activating cellular senescence. These observations suggest that HDACi and intercalating agents act more efficiently in combination to destroy tumor cells and their stem cells.

  12. 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

    of more sensitive methods including real-time PCR (RT-PCR). Immunohistochemistry with mutation-specific antibodies might be a promising detection method. We evaluated 210 samples with NSCLC from an unselected Caucasian population. Extracted DNA was analyzed for EGFR mutations by RT-PCR (Therascreen EGFR......, and staining score (multipum of intensity (graded 0-3) and percentages (0-100%) of stained tumor cells) was calculated. Positivity was defined as staining score >0. Specificity of exon19 antibody was 98.8% (95% confidence interval=95.9-99.9%) and of exon21 antibody 97.8% (95% confidence interval=94...... was demonstrated. However, sensitivity was low, especially for exon19 deletions, and thus these antibodies cannot yet be used as screening method for EGFR mutations in NSCLC. Refinement of sensitivity for the mutation-specific antibodies is warranted to improve molecular diagnosis using EGFR immunohistochemistry....

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

    International Nuclear Information System (INIS)

    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. -- Highlights: ► In the present study sodium butyrate (10 mM) induced mild apoptosis of cancer cells. ► The apoptosis was negatively regulated by cytoplasmic Sphingosine Kinase 2 (SphK2). ► Translocation of SphK2 from nucleus to cytoplasm was mediated by protein kinase D. ► Downregulation of SphK2 or protein kinase D leads to sensitized cell apoptosis.

  14. 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.

  15. The Novel miR-9600 Suppresses Tumor Progression and Promotes Paclitaxel Sensitivity in Non–small-cell Lung Cancer Through Altering STAT3 Expression

    Directory of Open Access Journals (Sweden)

    Cheng-Cao Sun

    2016-01-01

    Full Text Available MicroRNAs have been identified to be involved in center stage of cancer biology. They accommodate cell proliferation and migration by negatively regulate gene expression either by hampering the translation of targeted mRNAs or by promoting their degradation. We characterized and identified the novel miR-9600 and its target in human non–small-cell lung cancer (NSCLC. Our results demonstrated that the miR-9600 were downregulated in NSCLC tissues and cells. It is confirmed that signal transducer and activator of transcription 3 (STAT3, a putative target gene, is directly inhibited by miR-9600. The miR-9600 markedly suppressed the protein expression of STAT3, but with no significant influence in corresponding mRNA levels, and the direct combination of miR-9600 and STAT3 was confirmed by a luciferase reporter assay. miR-9600 inhibited cell growth, hampered expression of cell cycle-related proteins and inhibited cell migration and invasion in human NSCLC cell lines. Further, miR-9600 significantly suppressed tumor growth in nude mice. Similarly, miR-9600 impeded tumorigenesis and metastasis through directly targeting STAT3. Furthermore, we identified that miR-9600 augmented paclitaxel and cisplatin sensitivity by downregulating STAT3 and promoting chemotherapy-induced apoptosis. These data demonstrate that miR-9600 might be a useful and novel therapeutic target for NSCLC.

  16. LncRNA MEG3 enhances cisplatin sensitivity in non-small cell lung cancer by regulating miR-21-5p/SOX7 axis

    Directory of Open Access Journals (Sweden)

    Wang P

    2017-10-01

    Full Text Available Pei Wang,* Dong Chen,* Hongbing Ma, Yong LiDepartment of Cardiothoracic Surgery, Huaihe Hospital of Henan University, Kaifeng, People’s Republic of China *These authors contributed equally to this work Background: Long noncoding RNAs (lncRNAs have been revealed to play essential role in drug resistance of multiple cancers. LncRNA MEG3 was previously reported to be associated with cisplatin (DDP resistance in non-small cell lung cancer (NSCLC cells. However, the molecular mechanism of MEG3 affecting DDP resistance in NSCLC remains to be further illustrated. In this study, we attempted to discuss whether MEG3 also could function as a competing endogenous RNA to regulate DDP resistance in NSCLC.Materials and methods: The expression of MEG3, miR-21-5p, and sex-determining region Y-box 7 (SOX7 in NSCLC tissues or cells was examined by quantitative real-time polymerase chain reaction (qRT-PCR. 3-(4,5-Dimethylthazol-2-yl-2,5-diphenyltetrazolium bromide (MTT, flow cytometry, and caspase-3 activity analysis were applied to assess the DDP sensitivity of NSCLC cells. The interaction between MEG3, miR-21-5p, and SOX7 was explored by luciferase reporter assay, RNA immunoprecipitation (RIP assay, qRT-PCR, and Western blot. Mouse NSCLC transplanted tumor was established to verify the functional role of MEG3 in DDP resistance in vivo.Results: MEG3 was downregulated in DDP-resistant NSCLC cells. Overexpression of MEG3 enhanced DDP sensitivity of NSCLC cells in vitro. MEG3 directly interacted with miR-21-5p and suppressed its expression. miR-21-5p significantly abolished the effects of MEG3 on DDP resistance via modulating cell proliferation and apoptosis. SOX7 was identified as a direct target of miR-21-5p and MEG3 positively regulated SOX7 expression by suppressing miR-21-5p. Moreover, MEG3 knockdown-induced pro-proliferative and anti-apoptotic effects were reversed in DDP-resistant NSCLC cells by upregulating SOX7. Furthermore, upregulation of MEG3 induced

  17. Synthetic Galectin-3 Inhibitor Increases Metastatic Cancer Cell Sensitivity to Taxol-Induced Apoptosis In Vitro and In Vivo

    Directory of Open Access Journals (Sweden)

    Vladislav V. Glinsky

    2009-09-01

    Full Text Available At present, there is no efficient curative therapy for cancer patients with advanced metastatic disease. Targeting of antiapoptotic molecules acting on the mitochondrial apoptosis pathway could potentially augment antimetastatic effect of cytotoxic drugs. Similarly to Bcl-2 family members, β-galactoside-binding lectin galectin-3 protects cancer cells from apoptosis induced by cytotoxic drugs through the mitochondrial pathway. In this study, we tested the hypothesis that inhibiting galectin-3 antiapoptotic function using a synthetic low-molecular weight carbohydrate-based compound lactulosyl-L-leucine (Lac-L-Leu will augment apoptosis induced in human cancer cells by paclitaxel and increase its efficacy against established metastases. Treatment with synthetic glycoamine Lac-L-Leu alone reduced the number of established MDA-MB-435Lung2 pulmonary metastases 5.5-fold (P = .032 but did not significantly affect the incidence of metastasis. Treatment with paclitaxel alone (10 mg/kg three times with 3-day intervals had no significant effect on the incidence or on the number of MDA-MB-435Lung2 metastases. Treatment with Lac-L-Leu/paclitaxel combination decreased both the number (P = .02 and the incidence (P = .001 of pulmonary metastases, causing a five-fold increase in the number of metastasis-free animals from 14% in the control group to 70% in the combination therapy group. The median number of lung metastases dropped to 0 in the combination therapy group compared with 11 in the control (P = .02. Synergistic inhibition of clonogenic survival and induction of apoptosis in metastatic cells by Lac-L-Leu/paclitaxel combination was functionally linked with an increase in mitochondrial damage and was sufficient for the antimetastatic activity that caused a reversal and eradication of advanced metastatic disease in 56% of experimental animals.

  18. Sublethal concentrations of 17-AAG suppress homologous recombination DNA repair and enhance sensitivity to carboplatin and olaparib in HR proficient ovarian cancer cells.

    Science.gov (United States)

    Choi, Young Eun; Battelli, Chiara; Watson, Jacqueline; Liu, Joyce; Curtis, Jennifer; Morse, Alexander N; Matulonis, Ursula A; Chowdhury, Dipanjan; Konstantinopoulos, Panagiotis A

    2014-05-15

    The promise of PARP-inhibitors(PARPis) in the management of epithelial ovarian cancer(EOC) is tempered by the fact that approximately 50% of patients with homologous recombination (HR)-proficient tumors do not respond well to these agents. Combination of PARPis with agents that inhibit HR may represent an effective strategy to enhance their activity in HR-proficient tumors. Using a bioinformatics approach, we identified that heat shock protein 90 inhibitors(HSP90i) may suppress HR and thus revert HR-proficient to HR-deficient tumors. Analysis of publicly available gene expression data showed that exposure of HR-proficient breast cancer cell lines to HSP90i 17-AAG(17-allylamino-17-demethoxygeldanamycin) downregulated HR, ATM and Fanconi Anemia pathways. In HR-proficient EOC cells, 17-AAG suppressed HR as assessed using the RAD51 foci formation assay and this was further confirmed using the Direct Repeat-GFP reporter assay. Furthermore, 17-AAG downregulated BRCA1 and/or RAD51 protein levels, and induced significantly more γH2AX activation in combination with olaparib compared to olaparib alone. Finally, sublethal concentrations of 17-AAG sensitized HR-proficient EOC lines to olaparib and carboplatin but did not affect sensitivity of the HR-deficient OVCAR8 line arguing that the 17-AAG mediated sensitization is dependent on suppression of HR. These results provide a preclinical rationale for using a combination of olaparib/17-AAG in HR-proficient EOC.

  19. MicroRNA-triggered, cascaded and catalytic self-assembly of functional ``DNAzyme ferris wheel'' nanostructures for highly sensitive colorimetric detection of cancer cells

    Science.gov (United States)

    Zhou, Wenjiao; Liang, Wenbin; Li, Xin; Chai, Yaqin; Yuan, Ruo; Xiang, Yun

    2015-05-01

    The construction of DNA nanostructures with various sizes and shapes has significantly advanced during the past three decades, yet the application of these DNA nanostructures for solving real problems is still in the early stage. On the basis of microRNA-triggered, catalytic self-assembly formation of the functional ``DNAzyme ferris wheel'' nanostructures, we show here a new signal amplification platform for highly sensitive, label-free and non-enzyme colorimetric detection of a small number of human prostate cancer cells. The microRNA (miR-141), which is catalytically recycled and reused, triggers isothermal self-assembly of a pre-designed, G-quadruplex sequence containing hairpin DNAs into ``DNAzyme ferris wheel''-like nanostructures (in association with hemin) with horseradish peroxidase mimicking activity. These DNAzyme nanostructures catalyze an intensified color transition of the probe solution for highly sensitive detection of miR-141 down to 0.5 pM with the naked eye, and the monitoring of as low as 283 human prostate cancer cells can also, theoretically, be achieved in a colorimetric approach. The work demonstrated here thus offers new opportunities for the construction of functional DNA nanostructures and for the application of these DNA nanostructures as an effective signal amplification means in the sensitive detection of nucleic acid biomarkers.

  20. High susceptibility of metastatic cells derived from human prostate and colon cancer cells to TRAIL and sensitization of TRAIL-insensitive primary cells to TRAIL by 4,5-dimethoxy-2-nitrobenzaldehyde

    Directory of Open Access Journals (Sweden)

    Lee Jae-Won

    2011-04-01

    Full Text Available Abstract Background Tumor recurrence and metastasis develop as a result of tumors' acquisition of anti-apoptotic mechanisms and therefore, it is necessary to develop novel effective therapeutics against metastatic cancers. In this study, we showed the differential TRAIL responsiveness of human prostate adenocarcinoma PC3 and human colon carcinoma KM12 cells and their respective highly metastatic PC3-MM2 and KM12L4A sublines and investigated the mechanism underlying high susceptibility of human metastatic cancer cells to TRAIL. Results PC3-MM2 and KM12L4A cells with high level of c-Myc and DNA-PKcs were more susceptible to TRAIL than their poorly metastatic primary PC3 and KM12 cells, which was associated with down-regulation of c-FLIPL/S and Mcl-1 and up-regulation of the TRAIL receptor DR5 but not DR4 in both metastatic cells. Moreover, high susceptibility of these metastatic cells to TRAIL was resulted from TRAIL-induced potent activation of caspase-8, -9, and -3 in comparison with their primary cells, which led to cleavage and down-regulation of DNA-PKcs. Knockdown of c-Myc gene in TRAIL-treated PC3-MM2 cells prevented the increase of DR5 cell surface expression, caspase activation and DNA-PKcs cleavage and attenuated the apoptotic effects of TRAIL. Moreover, the suppression of DNA-PKcs level with siRNA in the cells induced the up-regulation of DR5 and active caspase-8, -9, and -3. We also found that 4,5-dimethoxy-2-nitrobenzaldehyde (DMNB, a specific inhibitor of DNA-PK, potentiated TRAIL-induced cytotoxicity and apoptosis in relatively TRAIL-insensitive PC3 and KM12 cells and therefore functioned as a TRAIL sensitizer. Conclusion This study showed the positive relationship between c-Myc expression in highly metastatic human prostate and colon cancer cells and susceptibility to TRAIL-induced apoptosis and therefore indicated that TRAIL might be used as an effective therapeutic modality for advanced metastatic cancers overexpressing c-Myc and

  1. Systematic assessment of multi-gene predictors of pan-cancer cell line sensitivity to drugs exploiting gene expression data [version 1; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Linh Nguyen

    2016-12-01

    Full Text Available Background: Selected gene mutations are routinely used to guide the selection of cancer drugs for a given patient tumour. Large pharmacogenomic data sets 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 IC50 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 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 multi-gene RF classifiers. Among the drugs with the most predictive of these models, we found pyrimethamine, sunitinib and 17-AAG. Conclusions: We now know that this type of models can predict in vitro tumour response to these drugs. These models can thus be further investigated on in vivo tumour models.

  2. Suppression of microRNA-629 enhances sensitivity of cervical cancer cells to 1′S-1′-acetoxychavicol acetate via regulating RSU1

    Directory of Open Access Journals (Sweden)

    Phuah NH

    2017-03-01

    Full Text Available Neoh Hun Phuah,1 Mohamad Nurul Azmi,2 Khalijah Awang,2 Noor Hasima Nagoor1,3 1Faculty of Science, Institute of Biological Science (Genetics and Molecular Biology, 2Faculty of Science, Department of Chemistry, Centre for Natural Product Research and Drug Discovery (CENAR, 3Centre for Research in Biotechnology for Agriculture (CEBAR, University of Malaya, Kuala Lumpur, Malaysia Background: Cervical cancer is the fourth most frequent malignancy affecting women worldwide, but drug resistance and toxicities remain a major challenge in chemotherapy. The use of natural compounds is promising because they are less toxic and able to target multiple signaling pathways. The 1'S-1'-acetoxychavicol acetate (ACA, a natural compound isolated from wild ginger Alpinia conchigera, induced cytotoxicity on various cancer cells including cervical cancer. MicroRNAs (miRNAs are short noncoding RNAs that regulate numerous biological processes, such as apoptosis and chemosensitivity. Past studies reported that miR-629 is upregulated in many cancers, and its expression was altered in ACA-treated cervical cancer cells. However, the role of miR-629 in regulating sensitivity toward ACA or other anticancer agents has not been reported. Hence, this study aims to investigate the role of miR-629 in regulating response toward ACA on cervical cancer cells.  Methods: The miR-629 expression following transfection with miR-629 hairpin inhibitor and hairpin inhibitor negative control was measured using quantitative real-time polymerase chain reaction (RT-qPCR. The 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide (MTT assay was used to investigate sensitivity toward ACA. Apoptosis was detected using Annexin V/propidium iodide and Caspase 3/7 assays. The gene target for miR-629 was identified using miRNA target prediction programs, luciferase reporter assay and Western blots. Gene overexpression studies were performed to evaluate its role in regulating response toward ACA

  3. Regulation of epidermal growth factor receptor signaling and erlotinib sensitivity in head and neck cancer cells by miR-7.

    Directory of Open Access Journals (Sweden)

    Felicity C Kalinowski

    Full Text Available Elevated expression and activity of the epidermal growth factor receptor (EGFR/protein kinase B (Akt signaling pathway is associated with development, progression and treatment resistance of head and neck cancer (HNC. Several studies have demonstrated that microRNA-7 (miR-7 regulates EGFR expression and Akt activity in a range of cancer cell types via its specific interaction with the EGFR mRNA 3'-untranslated region (3'-UTR. In the present study, we found that miR-7 regulated EGFR expression and Akt activity in HNC cell lines, and that this was associated with reduced growth in vitro and in vivo of cells (HN5 that were sensitive to the EGFR tyrosine kinase inhibitor (TKI erlotinib (Tarceva. miR-7 acted synergistically with erlotinib to inhibit growth of erlotinib-resistant FaDu cells, an effect associated with increased inhibition of Akt activity. Microarray analysis of HN5 and FaDu cell lines transfected with miR-7 identified a common set of downregulated miR-7 target genes, providing insight into the tumor suppressor function of miR-7. Furthermore, we identified several target miR-7 mRNAs with a putative role in the sensitization of FaDu cells to erlotinib. Together, these data support the coordinate regulation of Akt signaling by miR-7 in HNC cells and suggest the therapeutic potential of miR-7 alone or in combination with EGFR TKIs in this disease.

  4. The ultra-sensitive Nodewalk technique identifies stochastic from virtual, population-based enhancer hubs regulating MYC in 3D: Implications for the fitness of cancer cells

    KAUST Repository

    Sumida, Noriyuki

    2018-03-27

    The relationship between stochastic transcriptional bursts and dynamic 3D chromatin states is not well understood due to poor sensitivity and/or resolution of current chromatin structure-based assays. Consequently, it is not well established if enhancers operate individually and/or in clusters to coordinate gene transcription. In the current study, we introduce Nodewalk, which uniquely combines high sensitivity with high resolution to enable the analysis of chromatin networks in minute input material. The >10,000-fold increase in sensitivity over other many-to-all competing methods uncovered that active chromatin hubs identified in large input material, corresponding to 10 000 cells, flanking the MYC locus are primarily virtual. Thus, the close agreement between chromatin interactomes generated from aliquots corresponding to less than 10 cells with randomly re-sampled interactomes, we find that numerous distal enhancers positioned within flanking topologically associating domains (TADs) converge on MYC in largely mutually exclusive manners. Moreover, when comparing with several enhancer baits, the assignment of the MYC locus as the node with the highest dynamic importance index, indicates that it is MYC targeting its enhancers, rather than vice versa. Dynamic changes in the configuration of the boundary between TADs flanking MYC underlie numerous stochastic encounters with a diverse set of enhancers to depict the plasticity of its transcriptional regulation. Such an arrangement might increase the fitness of the cancer cell by increasing the probability of MYC transcription in response to a wide range of environmental cues encountered by the cell during the neoplastic process.

  5. The ultra-sensitive Nodewalk technique identifies stochastic from virtual, population-based enhancer hubs regulating MYC in 3D: Implications for the fitness of cancer cells

    KAUST Repository

    Sumida, Noriyuki; Sifakis, Emmanouil; Scholz, Barbara A; Fernandez Woodbridge, Alejandro; Kiani, Narsis A.; Gomez-Cabrero, David; Svensson, J Peter; Tegner, Jesper; Gondor, Anita; Ohlsson, Rolf

    2018-01-01

    The relationship between stochastic transcriptional bursts and dynamic 3D chromatin states is not well understood due to poor sensitivity and/or resolution of current chromatin structure-based assays. Consequently, it is not well established if enhancers operate individually and/or in clusters to coordinate gene transcription. In the current study, we introduce Nodewalk, which uniquely combines high sensitivity with high resolution to enable the analysis of chromatin networks in minute input material. The >10,000-fold increase in sensitivity over other many-to-all competing methods uncovered that active chromatin hubs identified in large input material, corresponding to 10 000 cells, flanking the MYC locus are primarily virtual. Thus, the close agreement between chromatin interactomes generated from aliquots corresponding to less than 10 cells with randomly re-sampled interactomes, we find that numerous distal enhancers positioned within flanking topologically associating domains (TADs) converge on MYC in largely mutually exclusive manners. Moreover, when comparing with several enhancer baits, the assignment of the MYC locus as the node with the highest dynamic importance index, indicates that it is MYC targeting its enhancers, rather than vice versa. Dynamic changes in the configuration of the boundary between TADs flanking MYC underlie numerous stochastic encounters with a diverse set of enhancers to depict the plasticity of its transcriptional regulation. Such an arrangement might increase the fitness of the cancer cell by increasing the probability of MYC transcription in response to a wide range of environmental cues encountered by the cell during the neoplastic process.

  6. 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)

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

    2017-01-01

    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

  7. Cytotoxicity of cancer HeLa cells sensitivity to normal MCF10A cells in cultivations with cell culture medium treated by microwave-excited atmospheric pressure plasmas

    Science.gov (United States)

    Takahashi, Yohei; Taki, Yusuke; Takeda, Keigo; Hashizume, Hiroshi; Tanaka, Hiromasa; Ishikawa, Kenji; Hori, Masaru

    2018-03-01

    Cytotoxic effects of human epithelial carcinoma HeLa cells sensitivity to human mammary epithelial MCF10A cells appeared in incubation with the plasma-activated medium (PAM), where the cell culture media were irradiated with the hollow-shaped contact of a continuously discharged plasma that was sustained by application of a microwave power under Ar gas flow at atmospheric pressure. The discharged plasma had an electron density of 7  ×  1014 cm-3. As the nozzle exit to the plasma source was a distance of 5 mm to the medium, concentrations of 180 µM for H2O2 and 77 µM for NO2- were generated in the PAM for 30 s irradiation, resulting in the control of irradiation periods for aqueous H2O2 with a generation rate of 6.0 µM s-1, and nitrite ion (NO2- ) with a rate of 2.2 µM s-1. Effective concentrations of H2O2 and NO2- for the antitumor effects were revealed in the microwave-excited PAM, with consideration of the complicated reactions at the plasma-liquid interfaces.

  8. 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

  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

    International Nuclear Information System (INIS)

    Thewes, Verena; Orso, Francesca; Jäger, Richard; Eckert, Dawid; Schäfer, Sabine; Kirfel, Gregor; Garbe, Stephan; Taverna, Daniela; Schorle, Hubert

    2010-01-01

    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. 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. 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. 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 ability to induce apoptosis. Therefore, interference

  10. The translational blocking of α5 and α6 integrin subunits affects migration and invasion, and increases sensitivity to carboplatin of SKOV-3 ovarian cancer cell line

    Energy Technology Data Exchange (ETDEWEB)

    Villegas-Pineda, Julio César, E-mail: jcvillegas@cinvestav.mx; Toledo-Leyva, Alfredo, E-mail: toledo_leyva@hotmail.com; Osorio-Trujillo, Juan Carlos, E-mail: clostrujillo2@yahoo.com.mx; Hernández-Ramírez, Verónica Ivonne, E-mail: arturomvi@hotmail.com; Talamás-Rohana, Patricia, E-mail: ptr@cinvestav.mx

    2017-02-15

    Epithelial ovarian cancer is the most lethal gynecologic malignancy. Integrins, overexpressed in cancer, are involved in various processes that favor the development of the disease. This study focused on determining the degree of involvement of α5, α6 and β3 integrin subunits in the establishment/development of epithelial ovarian cancer (EOC), such as proliferation, migration, invasion, and response to carboplatin. The translation of the α5, α6 and β3 integrins was blocked using morpholines, generating morphant cells for these proteins, which were corroborated by immunofluorescence assays. WST-1 proliferation assay showed that silencing of α5, α6, and β3 integrins does not affect the survival of morphants. Wound healing and transwell chamber assays showed that blocking α5 and α6 integrins decrease, in lesser and greater level respectively, the migratory and the invasive capacity of SKOV-3 cells. Finally, blocking α5 and α6 integrins partially sensitized the cells response to carboplatin, while blocking integrin β3 generated resistance to this drug. Statistical analyses were performed with the GraphPad Prism 5.0 software employing one way and two-way ANOVA tests; data are shown as average±SD. Results suggest that α5 and α6 integrins could become good candidates for chemotherapy targets in EOC.

  11. Reactivating p53 and Inducing Tumor Apoptosis (RITA Enhances the Response of RITA-Sensitive Colorectal Cancer Cells to Chemotherapeutic Agents 5-Fluorouracil and Oxaliplatin

    Directory of Open Access Journals (Sweden)

    Armin Wiegering

    2017-04-01

    Full Text Available Colorectal carcinoma (CRC is the most common cancer of the gastrointestinal tract with frequently dysregulated intracellular signaling pathways, including p53 signaling. The mainstay of chemotherapy treatment of CRC is 5-fluorouracil (5FU and oxaliplatin. The two anticancer drugs mediate their therapeutic effect via DNA damage-triggered signaling. The small molecule reactivating p53 and inducing tumor apoptosis (RITA is described as an activator of wild-type and reactivator of mutant p53 function, resulting in elevated levels of p53 protein, cell growth arrest, and cell death. Additionally, it has been shown that RITA can induce DNA damage signaling. It is expected that the therapeutic benefits of 5FU and oxaliplatin can be increased by enhancing DNA damage signaling pathways. Therefore, we highlighted the antiproliferative response of RITA alone and in combination with 5FU or oxaliplatin in human CRC cells. A panel of long-term established CRC cell lines (n = 9 including p53 wild-type, p53 mutant, and p53 null and primary patient-derived, low-passage cell lines (n = 5 with different p53 protein status were used for this study. A substantial number of CRC cells with pronounced sensitivity to RITA (IC50< 3.0 μmol/l were identified within established (4/9 and primary patient-derived (2/5 CRC cell lines harboring wild-type or mutant p53 protein. Sensitivity to RITA appeared independent of p53 status and was associated with an increase in antiproliferative response to 5FU and oxaliplatin, a transcriptional increase of p53 targets p21 and NOXA, and a decrease in MYC mRNA. The effect of RITA as an inducer of DNA damage was shown by a strong elevation of phosphorylated histone variant H2A.X, which was restricted to RITA-sensitive cells. Our data underline the primary effect of RITA, inducing DNA damage, and demonstrate the differential antiproliferative effect of RITA to CRC cells independent of p53 protein status. We found a substantial number

  12. Time- and cell-resolved dynamics of redox-sensitive Nrf2, HIF and NF-κB activities in 3D spheroids enriched for cancer stem cells

    Directory of Open Access Journals (Sweden)

    Anna P. Kipp

    2017-08-01

    Full Text Available Cancer cells have an altered redox status, with changes in intracellular signaling pathways. The knowledge of how such processes are regulated in 3D spheroids, being well-established tumor models, is limited. To approach this question we stably transfected HCT116 cells with a pTRAF reporter that enabled time- and cell-resolved activity monitoring of three redox-regulated transcription factors Nrf2, HIF and NF-κB in spheroids enriched for cancer stem cells. At the first day of spheroid formation, these transcription factors were activated and thereafter became repressed. After about a week, both HIF and Nrf2 were reactivated within the spheroid cores. Further amplifying HIF activation in spheroids by treatment with DMOG resulted in a dominant quiescent stem-cell-like phenotype, with high resistance to stress-inducing treatments. Auranofin, triggering oxidative stress and Nrf2 activation, had opposite effects with increased differentiation and proliferation. These novel high-resolution insights into spatiotemporal activation patterns demonstrate a striking coordination of redox regulated transcription factors within spheroids not occurring in conventional cell culture models. Keywords: Redox regulation, Cancer stem cells, Spheroids, Nrf2, HIF, NF-κB

  13. 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.

  14. 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.

  15. Systematic assessment of multi-gene predictors of pan-cancer cell line sensitivity to drugs exploiting gene expression data [version 2; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Linh Nguyen

    2017-03-01

    Full Text Available 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 IC50 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

  16. Antisense-MDM2 Sensitizes LNCaP Prostate Cancer Cells to Androgen Deprivation, Radiation, and the Combination In Vivo

    International Nuclear Information System (INIS)

    Stoyanova, Radka; Hachem, Paul; Hensley, Harvey; Khor, L.-Y.; Mu Zhaomei; Hammond, M. Elizabeth H.; Agrawal, Sudhir; Pollack, Alan

    2007-01-01

    Purpose: To test the effects of antisense (AS)-MDM2 alone and with androgen deprivation (AD), radiotherapy (RT), and AD + RT on wild-type LNCaP cells in an orthotopic in vivo model. Methods: Androgen-sensitive LNCaP cells were grown in the prostates of nude mice. Magnetic resonance imaging-based tumor volume and serum prostate-specific antigen (PSA) measurements were used to assess effects on tumor response. Tumor response was measured by biochemical and tumor volume failure definitions and doubling time estimates from fitted PSA and tumor volume growth curves. Expression of MDM2, p53, p21, and Ki-67 was quantified using immunohistochemical staining and image analysis of formalin-fixed tissue, analogous to methods used clinically. Results: Antisense-MDM2 significantly inhibited the growth of LNCaP tumors over the mismatch controls. The most significant increase in tumor growth delay and tumor doubling time was from AS-MDM2 + AD + RT, although the effect of AS-MDM2 + AD was substantial. Expression of MDM2 was significantly reduced by AS-MDM2 in the setting of RT. Conclusions: This is the first in vivo investigation of the effects of AS-MDM2 in an orthotopic model and the first to demonstrate incremental sensitization when added to AD and AD + RT. The results with AD underscore the potential to affect micrometastatic disease, which is probably responsible for treatment failure in 30-40% of men with high-risk disease

  17. Highly sensitive detection of ESR1 mutations in cell-free DNA from patients with metastatic breast cancer using molecular barcode sequencing.

    Science.gov (United States)

    Masunaga, Nanae; Kagara, Naofumi; Motooka, Daisuke; Nakamura, Shota; Miyake, Tomohiro; Tanei, Tomonori; Naoi, Yasuto; Shimoda, Masafumi; Shimazu, Kenzo; Kim, Seung Jin; Noguchi, Shinzaburo

    2018-01-01

    We aimed to develop a highly sensitive method to detect ESR1 mutations in cell-free DNA (cfDNA) using next-generation sequencing with molecular barcode (MB-NGS) targeting the hotspot segment (c.1600-1713). The sensitivity of MB-NGS was tested using serially diluted ESR1 mutant DNA and then cfDNA samples from 34 patients with metastatic breast cancer were analyzed with MB-NGS. The results of MB-NGS were validated in comparison with conventional NGS and droplet digital PCR (ddPCR). MB-NGS showed a higher sensitivity (0.1%) than NGS without barcode (1%) by reducing background errors. Of the cfDNA samples from 34 patients with metastatic breast cancer, NGS without barcode revealed seven mutations in six patients (17.6%) and MB-NGS revealed six additional mutations including three mutations not reported in the COSMIC database of breast cancer, resulting in total 13 ESR1 mutations in ten patients (29.4%). Regarding the three hotspot mutations, all the patients with mutations detected by MB-NGS had identical mutations detected by droplet digital PCR (ddPCR), and mutant allele frequency correlated very well between both (r = 0.850, p < 0.01). Moreover, all the patients without these mutations by MB-NGS were found to have no mutations by ddPCR. In conclusion, MB-NGS could successfully detect ESR1 mutations in cfDNA with a higher sensitivity of 0.1% than conventional NGS and was considered as clinically useful as ddPCR.

  18. Modulating lysosomal function through lysosome membrane permeabilization or autophagy suppression restores sensitivity to cisplatin in refractory non-small-cell lung cancer cells.

    Science.gov (United States)

    Circu, Magdalena; Cardelli, James; Barr, Martin; O'Byrne, Kenneth; Mills, Glenn; El-Osta, Hazem

    2017-01-01

    Lung cancer is the leading cause of cancer-related deaths. Most patients develop resistance to platinum within several months of treatment. We investigated whether triggering lysosomal membrane permeabilization (LMP) or suppressing autophagy can restore cisplatin susceptibility in lung cancer with acquired chemoresistance. Cisplatin IC50 in A549Pt (parental) and A549cisR (cisplatin resistant) cells was 13 μM and 47 μM, respectively. Following cisplatin exposure, A549cisR cells failed to elicit an apoptotic response. This was manifested by diminished Annexin-V staining, caspase 3 and 9, BAX and BAK activation in resistant but not in parental cells. Chloroquine preferentially promoted LMP in A549cisR cells, revealed by leakage of FITC-dextran into the cytosol as detected by immunofluorescence microscopy. This was confirmed by increased cytosolic cathepsin D signal on Immunoblot. Cell viability of cisplatin-treated A549cisR cells was decreased when co-treated with chloroquine, corresponding to a combination index below 0.8, suggesting synergism between the two drugs. Notably, chloroquine activated the mitochondrial cell death pathway as indicated by increase in caspase 9 activity. Interestingly, inhibition of lysosomal proteases using E64 conferred cytoprotection against cisplatin and chloroquine co-treatment, suggesting that chloroquine-induced cell death occurred in a cathepsin-mediated mechanism. Likewise, blockage of caspases partially rescued A549cisR cells against the cytotoxicity of cisplatin and chloroquine combination. Cisplatin promoted a dose-dependent autophagic flux induction preferentially in A549cisR cells, as evidenced by a surge in LC3-II/α-tubulin following pre-treatment with E64 and increase in p62 degradation. Compared to untreated cells, cisplatin induced an increase in cyto-ID-loaded autophagosomes in A549cisR cells that was further amplified by chloroquine, pointing toward autophagic flux activation by cisplatin. Interestingly, this effect

  19. Modulating lysosomal function through lysosome membrane permeabilization or autophagy suppression restores sensitivity to cisplatin in refractory non-small-cell lung cancer cells.

    Directory of Open Access Journals (Sweden)

    Magdalena Circu

    Full Text Available Lung cancer is the leading cause of cancer-related deaths. Most patients develop resistance to platinum within several months of treatment. We investigated whether triggering lysosomal membrane permeabilization (LMP or suppressing autophagy can restore cisplatin susceptibility in lung cancer with acquired chemoresistance. Cisplatin IC50 in A549Pt (parental and A549cisR (cisplatin resistant cells was 13 μM and 47 μM, respectively. Following cisplatin exposure, A549cisR cells failed to elicit an apoptotic response. This was manifested by diminished Annexin-V staining, caspase 3 and 9, BAX and BAK activation in resistant but not in parental cells. Chloroquine preferentially promoted LMP in A549cisR cells, revealed by leakage of FITC-dextran into the cytosol as detected by immunofluorescence microscopy. This was confirmed by increased cytosolic cathepsin D signal on Immunoblot. Cell viability of cisplatin-treated A549cisR cells was decreased when co-treated with chloroquine, corresponding to a combination index below 0.8, suggesting synergism between the two drugs. Notably, chloroquine activated the mitochondrial cell death pathway as indicated by increase in caspase 9 activity. Interestingly, inhibition of lysosomal proteases using E64 conferred cytoprotection against cisplatin and chloroquine co-treatment, suggesting that chloroquine-induced cell death occurred in a cathepsin-mediated mechanism. Likewise, blockage of caspases partially rescued A549cisR cells against the cytotoxicity of cisplatin and chloroquine combination. Cisplatin promoted a dose-dependent autophagic flux induction preferentially in A549cisR cells, as evidenced by a surge in LC3-II/α-tubulin following pre-treatment with E64 and increase in p62 degradation. Compared to untreated cells, cisplatin induced an increase in cyto-ID-loaded autophagosomes in A549cisR cells that was further amplified by chloroquine, pointing toward autophagic flux activation by cisplatin

  20. Melatonin disturbs SUMOylation mediated crosstalk between c-Myc and Nestin via MT1 activation and promotes the sensitivity of Paclitaxel in brain cancer stem cells.

    Science.gov (United States)

    Lee, Hyemin; Lee, Hyo-Jung; Jung, Ji Hoon; Shin, Eun Ah; Kim, Sung-Hoon

    2018-04-14

    Here the underlying antitumor mechanism of melatonin and its potency as a sensitizer of Paclitaxel was investigated in X02 cancer stem cells. Melatonin suppressed sphere formation and induced G2/M arrest in X02 cells expressing Nestin, CD133, CXCR4 and SOX-2 as biomarkers of stemness. Furthermore, melatonin reduced the expression of CDK2, CDK4, cyclin D1, cyclin E, and c-Myc and upregulated cyclin B1 in X02 cells. Notably, genes of c-Myc related mRNAs were differentially expressed in melatonin treated X02 cells by microarray analysis. Consistently, melatonin reduced the expression of c-Myc at mRNA and protein levels, which was blocked by MG132. Of note, overexpression of c-Myc increased the expression of Nestin, while overexpression of Nestin enhanced c-Myc through crosstalk despite different locations, nucleus and cytoplasm. Interestingly, melatonin attenuated small ubiquitin-related modifier-1 (SUMO-1) more than SUMO-2 or SUMO-3 and disturbed nuclear translocation of Nestin for direct binding to c-Myc by SUMOylation of SUMO-1 protein by immunofluorescence and immunoprecipitation. Also, melatonin reduced trimethylated histone H3K4me3 and H3K36me3 more than dimethylation in X02 cells by Western blotting and Chromatin immunoprecipitation assay. Notably, melatonin upregulated MT1, not MT2, in X02 cells and melatonin receptor inhibitor Luzindole blocked the ability of melatonin to decrease the expression of Nestin, p-c-Myc(S62) and c-Myc. Furthermore, melatonin promoted cytotoxicity, sub G1 accumulation and apoptotic body formation by Paclitaxcel in X02 cells. Taken together, these findings suggest that melatonin inhibits stemness via suppression of c-Myc, Nestin, and histone methylation via MT1 activation and promotes anticancer effect of Paclitaxcel in brain cancer stem cells. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  1. Association of cancer metabolism-related proteins with oral carcinogenesis – indications for chemoprevention and metabolic sensitizing of oral squamous cell carcinoma?

    Science.gov (United States)

    2014-01-01

    Background Tumor metabolism is a crucial factor for the carcinogenesis of oral squamous cell carcinoma (OSCC). Methods Expression of IGF-R1, glycolysis-related proteins (GLUT-1, HK 2, PFK-1, LDHA, TKTL1), mitochondrial enzymes (SDHA, SDHB, ATP synthase) were analyzed in normal oral mucosa (n = 5), oral precursor lesions (simple hyperplasia, n = 11; squamous intraepithelial neoplasia, SIN I-III, n = 35), and OSCC specimen (n = 42) by immunohistochemistry and real-time polymerase chain reaction (qPCR) analysis in OSCC cell lines. Metabolism-related proteins were correlated with proliferation activity (Ki-67) and apoptotic properties (TUNEL assay) in OSCC. Specificity of antibodies was confirmed by western blotting in cancer cell lines. Results Expression of IGF-R1, glycolysis-related proteins (GLUT-1, HK 2, LDHA, TKTL1), and mitochondrial enzymes (SDHA, SDHB, ATP synthase) were significantly increased in the carcinogenesis of OSCC. Metabolic active regions of OSCC were strongly correlated with proliferating cancer (Ki-67+) cells without detection of apoptosis (TUNEL assay). Conclusions This study provides the first evidence of the expression of IGF-R1, glycolysis-related proteins GLUT-1, HK 2, PFK-1, LDHA, and TKTL1, as well as mitochondrial enzymes SDHA, SDHB, and ATP synthase in the multi-step carcinogenesis of OSCC. Both, hypoxia-related glucose metabolism and mitochondrial oxidative phosphorylation characteristics are associated with the carcinogenesis of OSCC. Acidosis and OXPHOS may drive a metabolic shift towards the pentose phosphate pathway (PPP). Therefore, inhibition of the PPP, glycolysis, and targeted anti-mitochondrial therapies (ROS generation) by natural compounds or synthetic vitamin derivatives may act as sensitizer for apoptosis in cancer cells mediated by adjuvant therapies in OSCC. PMID:25048361

  2. 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 ...

  3. Hypoxic human cancer cells are sensitized to BH-3 mimetic–induced apoptosis via downregulation of the Bcl-2 protein Mcl-1

    OpenAIRE

    Harrison, Luke R.E.; Micha, Dimitra; Brandenburg, Martin; Simpson, Kathryn L.; Morrow, Christopher J.; Denneny, Olive; Hodgkinson, Cassandra; Yunus, Zaira; Dempsey, Clare; Roberts, Darren; Blackhall, Fiona; Makin, Guy; Dive, Caroline

    2011-01-01

    Solid tumors contain hypoxic regions in which cancer cells are often resistant to chemotherapy-induced apoptotic cell death. Therapeutic strategies that specifically target hypoxic cells and promote apoptosis are particularly appealing, as few normal tissues experience hypoxia. We have found that the compound ABT-737, a Bcl-2 homology domain 3 (BH-3) mimetic, promotes apoptotic cell death in human colorectal carcinoma and small cell lung cancer cell lines exposed to hypoxia. This hypoxic indu...

  4. Intervention with the hypoxic tumor cell sensitizer etanidazole in the combined modality treatment of limited stage small-cell lung cancer. A one-institution study

    International Nuclear Information System (INIS)

    Urtasun, Raul C.; Palmer, Martin; Kinney, Brenda; Belch, Andrew; Hewitt, Joanne; Hanson, John

    1998-01-01

    Purpose: We report the toxicity, patterns of failure and survival of a cohort of patients with limited disease (LD) small-cell lung cancer (SCLC) treated with combined radiation and chemotherapy. During the course of thoracic irradiation, we added intravenous (i.v.) etanidazole (SR-2508, a third-generation 2-nitroimidazole) as a hypoxic cell sensitizer in an attempt to reduce the primary local failure rate and improve survival. Methods and Materials: Between July 1988 and August 1990, 30 consecutive patients with limited disease SCLC were enrolled and treated on a Phase II protocol receiving a standard combination chemotherapy regimen utilizing i.v. cisplatin 25 mg/m 2 /day x 3 days, i.v. etoposide 100 mg/m 2 /day x 3 days alternating with intravenous cyclophosphamide 1000 mg/m 2 /day, intravenous doxorubicin 15 mg/m 2 , and intravenous vincristine 2 mg (CAV) to a total of six cycles every 3 weeks. Radiotherapy and etanidazole were started after the first cycle of chemotherapy. Etanidazole was administered intravenously at a dose of 2 g/m 2 three times per week for a total of 30 g/m 2 during the course of thoracic radiation that delivered 50.00 Gy tumor dose in 25 fractions in an overall time of 6 weeks. Results: The overall response rate of the primary lesion in the thorax was 96% (CR + PR), with 64% complete responses. The median time to treatment failure was 18 months. Of the patients that have relapsed, only 18% failed in the thorax (alone or concomitant with other sites). This is a marked improvement compared to the 40-50% rate reported in the literature. The 2-year crude survival was 46%. The 3- and 5-year crude survival rate with no evidence of disease was 33 and 30%, respectively. We have observed a 10% increase in the incidence of transient etanidazole related peripheral neuropathies compared to previous etanidazole studies not utilizing systemic chemotherapy. There was no increased incidence of radiation esophagitis, pulmonary toxicity, or nephro- or

  5. Reactivating p53 and Inducing Tumor Apoptosis (RITA) Enhances the Response of RITA-Sensitive Colorectal Cancer Cells to Chemotherapeutic Agents 5-Fluorouracil and Oxaliplatin.

    Science.gov (United States)

    Wiegering, Armin; Matthes, Niels; Mühling, Bettina; Koospal, Monika; Quenzer, Anne; Peter, Stephanie; Germer, Christoph-Thomas; Linnebacher, Michael; Otto, Christoph

    2017-04-01

    Colorectal carcinoma (CRC) is the most common cancer of the gastrointestinal tract with frequently dysregulated intracellular signaling pathways, including p53 signaling. The mainstay of chemotherapy treatment of CRC is 5-fluorouracil (5FU) and oxaliplatin. The two anticancer drugs mediate their therapeutic effect via DNA damage-triggered signaling. The small molecule reactivating p53 and inducing tumor apoptosis (RITA) is described as an activator of wild-type and reactivator of mutant p53 function, resulting in elevated levels of p53 protein, cell growth arrest, and cell death. Additionally, it has been shown that RITA can induce DNA damage signaling. It is expected that the therapeutic benefits of 5FU and oxaliplatin can be increased by enhancing DNA damage signaling pathways. Therefore, we highlighted the antiproliferative response of RITA alone and in combination with 5FU or oxaliplatin in human CRC cells. A panel of long-term established CRC cell lines (n=9) including p53 wild-type, p53 mutant, and p53 null and primary patient-derived, low-passage cell lines (n=5) with different p53 protein status were used for this study. A substantial number of CRC cells with pronounced sensitivity to RITA (IC 50 RITA appeared independent of p53 status and was associated with an increase in antiproliferative response to 5FU and oxaliplatin, a transcriptional increase of p53 targets p21 and NOXA, and a decrease in MYC mRNA. The effect of RITA as an inducer of DNA damage was shown by a strong elevation of phosphorylated histone variant H2A.X, which was restricted to RITA-sensitive cells. Our data underline the primary effect of RITA, inducing DNA damage, and demonstrate the differential antiproliferative effect of RITA to CRC cells independent of p53 protein status. We found a substantial number of RITA-sensitive CRC cells within both panels of established CRC cell lines and primary patient-derived CRC cell lines (6/14) that provide a rationale for combining RITA with 5FU or

  6. 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

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

    International Nuclear Information System (INIS)

    Wolfe, Adam R.; Atkinson, Rachel L.; Reddy, Jay P.; Debeb, Bisrat G.; Larson, Richard; Li, Li; Masuda, Hiroko; Brewer, Takae; Atkinson, Bradley J.; Brewster, Abeena; Ueno, Naoto T.; Woodward, Wendy A.

    2015-01-01

    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

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

    DEFF Research Database (Denmark)

    Deng, Xiaohong; Fogh, Louise; Lademann, Ulrik Axel

    2013-01-01

    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...... to trastuzumab and lapatinib....

  9. Bioluminescent human breast cancer cell lines that permit rapid and sensitive in vivo detection of mammary tumors and multiple metastases in immune deficient mice

    International Nuclear Information System (INIS)

    Jenkins, Darlene E; Hornig, Yvette S; Oei, Yoko; Dusich, Joan; Purchio, Tony

    2005-01-01

    Our goal was to generate xenograft mouse models of human breast cancer based on luciferase-expressing MDA-MB-231 tumor cells that would provide rapid mammary tumor growth; produce metastasis to clinically relevant tissues such as lymph nodes, lung, and bone; and permit sensitive in vivo detection of both primary and secondary tumor sites by bioluminescent imaging. Two clonal cell sublines of human MDA-MB-231 cells that stably expressed firefly luciferase were isolated following transfection of the parental cells with luciferase cDNA. Each subline was passaged once or twice in vivo to enhance primary tumor growth and to increase metastasis. The resulting luciferase-expressing D3H1 and D3H2LN cells were analyzed for long-term bioluminescent stability, primary tumor growth, and distal metastasis to lymph nodes, lungs, bone and soft tissues by bioluminescent imaging. Cells were injected into the mammary fat pad of nude and nude-beige mice or were delivered systemically via intracardiac injection. Metastasis was also evaluated by ex vivo imaging and histologic analysis postmortem. The D3H1 and D3H2LN cell lines exhibited long-term stable luciferase expression for up to 4–6 months of accumulative tumor growth time in vivo. Bioluminescent imaging quantified primary mammary fat pad tumor development and detected early spontaneous lymph node metastasis in vivo. Increased frequency of spontaneous lymph node metastasis was observed with D3H2LN tumors as compared with D3H1 tumors. With postmortem ex vivo imaging, we detected additional lung micrometastasis in mice with D3H2LN mammary tumors. Subsequent histologic evaluation of tissue sections from lymph nodes and lung lobes confirmed spontaneous tumor metastasis at these sites. Following intracardiac injection of the MDA-MB-231-luc tumor cells, early metastasis to skeletal tissues, lymph nodes, brain and various visceral organs was detected. Weekly in vivo imaging data permitted longitudinal analysis of metastasis at

  10. 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

    Three small cell lung cancer cell lines established from a single patient during longitudinal follow-up were examined for in vitro expression of TGF beta and TGF beta receptors, i.e. the components of an autocrine loop. GLC 14 was established prior to treatment, GLC 16 on relapse after chemotherapy...... 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...... II receptor gene, as examined by Southern blotting. Also, the type I receptor could not be detected by ligand binding assay in this cell line, despite expression of mRNA for this receptor. This agrees with previous findings that type I receptor cannot bind TGF beta 1 without co-expression of the type...

  11. 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

  12. Collagen gel droplet-embedded culture drug sensitivity test for adjuvant chemotherapy after complete resection of non-small-cell lung cancer.

    Science.gov (United States)

    Inoue, Masayoshi; Maeda, Hajime; Takeuchi, Yukiyasu; Fukuhara, Kenjiro; Shintani, Yasushi; Funakoshi, Yasunobu; Funaki, Soichiro; Nojiri, Takashi; Kusu, Takashi; Kusumoto, Hidenori; Kimura, Toru; Okumura, Meinoshin

    2018-04-01

    We conducted a prospective clinical study to individualize adjuvant chemotherapy after complete resection of non-small-cell lung cancer (NSCLC), based on the drug sensitivity test. Patients with resectable c-stage IB-IIIA NSCLC were registered between 2005 and 2010. We performed the collagen gel droplet-embedded culture drug sensitivity test (CD-DST) on a fresh surgical specimen to assess in vitro chemosensitivity and evaluated the prognostic outcome after adjuvant chemotherapy with carboplatin/paclitaxel based on the CD-DST. Among 92 registered patients, 87 were eligible for inclusion in the analysis. The success rate of CD-DST was 86% and chemosensitivity to carboplatin and/or paclitaxel was evident in 57 (76%) of the 75 patients. Adjuvant chemotherapy was completed in 22 (73%) of 30 patients. The 5-year overall survival rates were 71, 73, and 75% for all, CD-DST success, and chemosensitive patients, respectively. The 5-year disease-free survival and overall survival rates of the chemosensitive patients who completed adjuvant chemotherapy using carboplatin/paclitaxel were 68 and 82%, respectively. The 5-year disease-free survival and overall survival rates of the patients with stage II-IIIA chemosensitive NSCLC were 58 and 75%, respectively. Comparative analyses of the chemosensitive and non-chemosensitive/CD-DST failure groups showed no significant survival difference. CD-DST can be used to evaluate chemosensitivity after lung cancer surgery; however, its clinical efficacy for assessing individualized treatment remains uncertain.

  13. 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.

  14. Knockdown of miR-27a sensitizes colorectal cancer stem cells to TRAIL by promoting the formation of Apaf-1-caspase-9 complex.

    Science.gov (United States)

    Zhang, Rui; Xu, Jian; Zhao, Jian; Bai, Jinghui

    2017-07-11

    MicroRNAs have been proved to participate in multiple biological processes in cancers. For developing resistance to cytotoxic drug, cancer cells, especially the cancer stem cells, usually change their microRNA expression profile to survive in hostile environments. In the present study, we found that expression of microRNA-27a was increased in colorectal cancer stem cells. High level of microRNA-27a was indicated to induce the resistance to TNF-related apoptosis-inducing ligand (TRAIL). Knockdown of microRNA-27a resensitized colorectal cancer stem cells to TRAIL-induced cell death. Mechanically, the gene of Apaf-1, which is associated with the mitochondrial apoptosis, was demonstrated to be the target of microRNA-27a in colorectal cancer stem cells. Knockdown of microRNA-27a increased the expression level of Apaf-1, thus enhancing the formation of Apaf-1-caspase-9 complex and subsequently promoting the TRAIL-induced apoptosis in colorectal cancer stem cells. These findings suggested that knockdown of microRNA-27a in colorectal cancer stem cells by the specific antioligonucleotides was potential to reverse the chemoresistance to TRAIL. It may represent a novel therapeutic strategy for treating the colorectal cancer more effectively.

  15. Hypoxia Potentiates the Radiation-Sensitizing Effect of Olaparib in Human Non-Small Cell Lung Cancer Xenografts by Contextual Synthetic Lethality

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Yanyan; Verbiest, Tom; Devery, Aoife M.; Bokobza, Sivan M.; Weber, Anika M.; Leszczynska, Katarzyna B.; Hammond, Ester M.; Ryan, Anderson J., E-mail: anderson.ryan@oncology.ox.ac.uk

    2016-06-01

    Purpose: Poly(ADP-ribose) polymerase (PARP) inhibitors potentiate radiation therapy in preclinical models of human non-small cell lung cancer (NSCLC) and other types of cancer. However, the mechanisms underlying radiosensitization in vivo are incompletely understood. Herein, we investigated the impact of hypoxia on radiosensitization by the PARP inhibitor olaparib in human NSCLC xenograft models. Methods and Materials: NSCLC Calu-6 and Calu-3 cells were irradiated in the presence of olaparib or vehicle under normoxic (21% O{sub 2}) or hypoxic (1% O{sub 2}) conditions. In vitro radiosensitivity was assessed by clonogenic survival assay and γH2AX foci assay. Established Calu-6 and Calu-3 subcutaneous xenografts were treated with olaparib (50 mg/kg, daily for 3 days), radiation (10 Gy), or both. Tumors (n=3/group) were collected 24 or 72 hours after the first treatment. Immunohistochemistry was performed to assess hypoxia (carbonic anhydrase IX [CA9]), vessels (CD31), DNA double strand breaks (DSB) (γH2AX), and apoptosis (cleaved caspase 3 [CC3]). The remaining xenografts (n=6/group) were monitored for tumor growth. Results: In vitro, olaparib showed a greater radiation-sensitizing effect in Calu-3 and Calu-6 cells in hypoxic conditions (1% O{sub 2}). In vivo, Calu-3 tumors were well-oxygenated, whereas Calu-6 tumors had extensive regions of hypoxia associated with down-regulation of the homologous recombination protein RAD51. Olaparib treatment increased unrepaired DNA DSB (P<.001) and apoptosis (P<.001) in hypoxic cells of Calu-6 tumors following radiation, whereas it had no significant effect on radiation-induced DNA damage response in nonhypoxic cells of Calu-6 tumors or in the tumor cells of well-oxygenated Calu-3 tumors. Consequently, olaparib significantly increased radiation-induced growth inhibition in Calu-6 tumors (P<.001) but not in Calu-3 tumors. Conclusions: Our data suggest that hypoxia potentiates the radiation-sensitizing effects of

  16. Choline kinase-alpha by regulating cell aggressiveness and drug sensitivity is a potential druggable target for ovarian cancer

    OpenAIRE

    Granata, A; Nicoletti, R; Tinaglia, V; De Cecco, L; Pisanu, M E; Ricci, A; Podo, F; Canevari, S; Iorio, E; Bagnoli, M; Mezzanzanica, D

    2013-01-01

    Background: Aberrant choline metabolism has been proposed as a novel cancer hallmark. We recently showed that epithelial ovarian cancer (EOC) possesses an altered MRS-choline profile, characterised by increased phosphocholine (PCho) content to which mainly contribute over-expression and activation of choline kinase-alpha (ChoK-alpha). Methods: To assess its biological relevance, ChoK-alpha expression was downmodulated by transient RNA interference in EOC in vitro models. Gene expression profi...

  17. 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

    The active form of vitamin D, 1,25-dihydroxyvitamin D(3) (1,25(OH)(2)D(3)) has anti-proliferative, pro-apoptotic, and pro-differentiating effects in somatic cancer cells in vitro and in vivo. 1,25(OH)(2)D(3) also augments the anti-tumor effects of several chemotherapeutic agents, including...... 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...

  18. 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

  19. Inhibition of WIP1 phosphatase sensitizes breast cancer cells to genotoxic stress and to MDM2 antagonist nutlin-3

    Czech Academy of Sciences Publication Activity Database

    Pecháčková, Soňa; Burdová, Kamila; Benada, Jan; Kleiblová, Petra; Jeníková, Gabriela; Macůrek, Libor

    2016-01-01

    Roč. 7, č. 12 (2016), s. 14458-14475 ISSN 1949-2553 R&D Projects: GA ČR GAP305/12/2485 Institutional support: RVO:68378050 Keywords : WIP1 inhibitor * breast cancer * checkpoint * nutlin-3 * p53 Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 5.168, year: 2016

  20. Streptokinase increases the sensitivity of colon cancer cells to chemotherapy by gemcitabine and cis-platine in vitro

    Czech Academy of Sciences Publication Activity Database

    Bobek, V.; Pintérová, D.; Kološtová, K.; Boubelík, Michael; Douglas, J.; Teyssler, P.; Pavlásek, J.; Kovařík, J.

    2006-01-01

    Roč. 237, č. 1 (2006), s. 95-101 ISSN 0304-3835 Institutional research plan: CEZ:AV0Z50520514 Keywords : chemotherapy * radiation * colon cancer Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.277, year: 2006

  1. Sensitization of (colon) cancer cells to death receptor related therapies A report from the FP6-ONCODEATH research consortium

    Czech Academy of Sciences Publication Activity Database

    Pintzas, A.; Zhivotovsky, B.; Workman, P.; Clarke, P.A.; Linardopoulos, S.; Martinou, J.C.; Lacal, J.C.; Robine, S.; Nasioulas, G.; Anděra, Ladislav

    2012-01-01

    Roč. 13, č. 7 (2012), s. 458-466 ISSN 1538-4047 Grant - others:EK(XE) LSHC-CT-2006-037278 Institutional support: RVO:68378050 Keywords : cancer * death receptors * kinase inhibitors * mitochondria * targeted therapies Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.287, year: 2012

  2. Rehydrating dye sensitized solar cells

    Directory of Open Access Journals (Sweden)

    Christian Hellert

    2017-05-01

    Full Text Available Dye sensitized solar cells (DSSCs are silicon free, simply producible solar cells. Longevity, however, is a longstanding problem for DSSCs. Due to liquid electrolytes being commonly used, evaporation of the electrolyte causes a dramatic drop in electric output as cells continue to be used unmaintained. Stopping evaporation has been tried in different ways in the past, albeit with differing degrees of success. In a recent project, a different route was chosen, exploring ways of revitalizing DSSCs after varying periods of usage. For this, we focused on rehydration of the cells using distilled water as well as the electrolyte contained in the cells. The results show a significant influence of these rehydration procedures on the solar cell efficiency. In possible applications of DSSCs in tents etc., morning dew may thus be used for rehydration of solar cells. Refillable DSSCs can also be used in tropical climates or specific types of farms and greenhouses where high humidity serves the purpose of rehydrating DSSCs.

  3. Association of polymorphism in TP53 gene with susceptibility and radiation sensitivity of non-small-cell-lung cancer in Chinese population

    International Nuclear Information System (INIS)

    Shao Guoguang; Liu Linlin; Xu Chuanjie

    2005-01-01

    Objective: To study the association of polymorphism in TP53 gene with the susceptibility and radiation sensitivity of non-small-cell-lung cancer (NSCLC) of the population in the North of China. Methods: Using RFLP-PCR assays, TP53 genotypes were detected by amplifying DNA fragments with sequence specific primers and digested by FnuD II enzyme in 88 patients with NSCLC as well as 112 healthy controls. Results: The C/C allele frequency was significantly higher in NSCLC patients than that in the healthy controls (χ 2 =5.65, P=0.017). The C/C genotype frequency was significantly higher in NSCLC patients than that of the healthy controls (χ 2 =9.33, P=0.0023). The risk of C/C homozygotes in NSCLC patients was about 2.7 times against G/G homozygotes with odds ratio of 2.43(95% CI=1.32-4.51). Conclusion: In the population in the North of China, TP53 C/C genotype is closely associated with the susceptibility of NSCLC. There is no significant relationship between the polymorphism in TP53 gene and radiation sensitivity in NSCLC. (authors)

  4. The sensitivity of radiation and its combined effect with anticancer drugs on cultured human lung cancer cells

    International Nuclear Information System (INIS)

    Okada, Shinichiro

    1986-01-01

    The cultured lung tumor cells were irradiated with 60 Co γ-rays, with and without combinations of adriamycin (ADR) and 5-Fluorouracil (5-FU). Cell survival was assayed by colony formation in vitro in soft agar and in plate. Most of small cell lung carcinoma cells used here were radiosensitive, while one of them showed radioresistent comparable to non-small cell lung tumors and other tumor cells. In the treatment with drugs (ADR or 5-FJ) following 60 Co γ-irradiation (postirradiation treatment), it proved to be twice as effective as drug treatment preceding irradiation (preirradiation treatment). Preirradiation treatment demonstrated that 5-FU treated cell were more radiosensitive than ADR treated ones. In the preirradiation treatment, the most enhanced killing effect was observed when cells were irradiated twenty four hours after 5-FU treatment, on the other hand, in the ADR treatment, treatment interval showed no differrece. In the postirradiation treatment, the greatest enhancement was observed when cells were irradiated twenty hours after ADR exposure, while most effective forty eight hours after 5-FU treatment. (author)

  5. 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.

  6. Radiation sensitivity of Merkell cell carcinoma cell lines

    International Nuclear Information System (INIS)

    Leonard, J. Helen; Ramsay, Jonathan R.; Kearsley, John H.; Birrell, Geoff W.

    1995-01-01

    Purpose: 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. Methods and Materials: 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 γ 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. Results: 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 γ 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. Conclusion: 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

  7. 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

  8. Proteasome inhibitor MG132 sensitizes HPV-positive human cervical cancer cells to rhTRAIL-induced apoptosis

    NARCIS (Netherlands)

    Hougardy, BMT; Maduro, JH; van der Zee, AGJ; de Groot, DJA; van den Heuvel, FAJ; de Vries, EGE; de Jong, S

    2006-01-01

    In cervical carcinogenesis, the p53 tumor suppressor pathway is disrupted by HPV (human papilloma virus) E6 oncogene expression. E6 targets p53 for rapid proteasome-mediated degradation. We therefore investigated whether proteasome inhibition by MG132 could restore wild-type p53 levels and sensitize

  9. 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.

  10. 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.

  11. Clinical evaluation of hypoxic cell sensitizer (Misonidazole)

    Energy Technology Data Exchange (ETDEWEB)

    Asakawa, Hiroshi (Miyagi Prefectural Adult Disease Center, Natori (Japan)); Watarai, Jiro; Hoshino, Toshiaki

    1984-06-01

    Clinical effectiveness and toxicity of Misonidazole were analyzed and discussed in 22 cases of carcinoma of uterine cervix, 17 cases of esophageal cancer and 11 with other malignancies treated by radiation. By clinical and histologic examination in the controlled trial, it was shown that radiation response of tumor was slightly sensitized in the treated group with this drug, compared with that in the control group. It was confirmed that there was no significant difference between radiation response of tumor in both groups. Peripheral neuropathy was a complication in 10% and toxicodermatitis in 12% even if the total dose administered was below 10 g/m/sup 2/. From these results, it was strongly suggested that this drug is not suitable in combination with simple fractionated irradiation as a hypoxic cell sensitizer.

  12. 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

  13. Metformin Causes G1-Phase Arrest via Down-Regulation of MiR-221 and Enhances TRAIL Sensitivity through DR5 Up-Regulation in Pancreatic Cancer Cells.

    Directory of Open Access Journals (Sweden)

    Ryoichi Tanaka

    Full Text Available Although many chemotherapeutic strategies against cancer have been developed, pancreatic cancer is one of the most aggressive and intractable types of malignancies. Therefore, new strategies and anti-cancer agents are necessary to treat this disease. Metformin is a widely used drug for type-2 diabetes, and is also known as a promising candidate anti-cancer agent from recent studies in vitro and in vivo. However, the mechanisms of metformin's anti-cancer effects have not been elucidated. We demonstrated that metformin suppressed the expression of miR-221, one of the most well-known oncogenic microRNAs, in human pancreatic cancer PANC-1 cells. Moreover, we showed that the down-regulation of miR-221 by metformin caused G1-phase arrest via the up-regulation of p27, one of the direct targets of miR-221. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL is also a promising agent for cancer treatment. While recent studies showed that treatment with only TRAIL was not effective against pancreatic cancer cells, the present data showed that metformin sensitized p53-mutated pancreatic cancer cells to TRAIL. Metformin induced the expressions of death receptor 5 (DR5, a receptor for TRAIL, and Bim with a pro-apoptotic function in the downstream of TRAIL-DR5 pathway. We suggest that the up-regulation of these proteins may contribute to sensitization of TRAIL-induced apoptosis. The combination therapy of metformin and TRAIL could therefore be effective in the treatment of pancreatic cancer.

  14. Andrographis paniculata elicits anti-invasion activities by suppressing TM4SF3 gene expression and by anoikis-sensitization in esophageal cancer cells

    Science.gov (United States)

    Yue, Grace Gar-Lee; Lee, Julia Kin-Ming; Li, Lin; Chan, Kar-Man; Wong, Eric Chun-Wai; Chan, Judy Yuet-Wah; Fung, Kwok-Pui; Lui, Vivian Wai Yan; Chiu, Philip Wai-Yan; Lau, Clara Bik-San

    2015-01-01

    Esophageal cancer is the sixth most common cancer in male causing death worldwide. It is usually diagnosed at advanced stage with high postoperative recurrence and systemic metastasis, which leads to poor prognosis. The potential inhibitory effect of herbal medicines on metastasis of esophageal cancer has drawn researchers’ great attention. In the present study, the anti-invasion activities of Andrographis paniculata (AP) have been evaluated in two esophageal cancer cell lines, EC-109 and KYSE-520, as well as human microvascular endothelial cells (HMEC-1). The anti-tumor and anti-metastatic activities of AP were also evaluated in human esophageal xenograft-bearing mouse models. Our results demonstrated for the first time that aqueous extract of AP inhibited the motility and invasion of esophageal cancer cells, which is the initial step of metastasis, without cytotoxicity. Anoikis resistance has also been reversed in AP-treated cancer cells. Besides, the expression of metastasis-related gene TM4SF3 in EC-109 cells was significantly decreased in AP extract-treated cells in a concentration-dependent manner. Furthermore, the anti-tumor and anti-metastatic efficacies in subcutaneous and intraperitoneal esophageal xenograft-bearing mice were demonstrated after oral administration of AP aqueous extract for 3 weeks. Last but not least, the active component, isoandrographolide, responsible for the anti-migratory activity was firstly revealed here. In conclusion, the AP aqueous extract exerted inhibitory activities on the migration and anoikis resistance of esophageal cancer cells EC-109 and KYSE-520, as well as suppressed the proliferation and motility of endothelial cells. Combining the mentioned effects may account for the anti-tumor and anti-metastasis effects of AP aqueous extract in xenograft-bearing mice. The findings in the present study further enhance the understanding of the therapeutic mechanisms of the herb AP, which may lead to clinical applications. PMID

  15. 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.

  16. Effect of Saw Palmetto Supplements on Androgen-Sensitive LNCaP Human Prostate Cancer Cell Number and Syrian Hamster Flank Organ Growth.

    Science.gov (United States)

    Opoku-Acheampong, Alexander B; Penugonda, Kavitha; Lindshield, Brian L

    2016-01-01

    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.

  17. Radiation sensitivity of mammalian cells

    International Nuclear Information System (INIS)

    Koch, C.J.

    1985-01-01

    The authors tested various aspects of the so-called ''competition'' model for radiation sensitization/protection. In this model, sensitizers and/or protectors react in first order chemical reactions with radiation-induced target radicals in the cell, producing damage fixation or repair respectively. It is only because of these parallel, first-order competing reactions that they may assign net amounts of damage on the basis of the chemical reactivity of the sentiziers/protectors with the radicals. It might be expected that such a simple model could not explain all aspects of cellular radiosensitivity and this has indeed been found to be true. However, one is able, with the simple model, to pose quite specific questions, and obtain quantitative information with respect to the relative agreement between experiment and theory. Many experiments by several investigators have found areas of disagreement with the competition theory, particularly with respect to the follow items: 1) role of cellular glutathione as the most important endogeneous radiation protector 2) characteristics of various sensitizers which cause them to behave differently from each other 3) methods relating to the quantitative kinetic analysis of experimenal results. This paper addresses these specific areas of disagreement from both an experimental and theoretical basis

  18. Silencing of NRF2 Reduces the Expression of ALDH1A1 and ALDH3A1 and Sensitizes to 5-FU in Pancreatic Cancer Cells

    Directory of Open Access Journals (Sweden)

    Hong-Quan Duong

    2017-07-01

    Full Text Available Pancreatic cancer remains an intractable cancer with a poor five-year survival rate, which requires new therapeutic modalities based on the biology of pancreatic oncogenesis. Nuclear factor E2 related factor-2 (NRF2, a key cytoprotective nuclear transcription factor, regulates antioxidant production, reduction, detoxification and drug efflux proteins. It also plays an essential role in cell homeostasis, cell proliferation and resistance to chemotherapy. We aimed to evaluate the possibility that modulation of NRF2 expression could be effective in the treatment of pancreatic cancer cells. We investigated whether the depletion of NRF2 by using small interfering RNAs (siRNAs is effective in the expression of biomarkers of pancreatic cancer stemness such as aldehyde dehydrogenase 1 family, member A1 (ALDH1A1 and aldehyde dehydrogenase 3 family, member A1 (ALDH3A1. NRF2 knockdown markedly reduced the expression of NRF2 and glutamate-cysteine ligase catalytic subunit (GCLC in cell lines established from pancreatic cancers. NRF2 silencing also decreased the ALDH1A1 and ALDH3A1 expression. Furthermore, this NRF2 depletion enhanced the antiproliferative effects of the chemotherapeutic agent, 5-fluorouracil (5-FU in pancreatic cancer cells.

  19. Colorectal cancer stem cells.

    Science.gov (United States)

    Salama, Paul; Platell, Cameron

    2009-10-01

    Somatic stem cells reside at the base of the crypts throughout the colonic mucosa. These cells are essential for the normal regeneration of the colonic epithelium. The stem cells reside within a special 'niche' comprised of intestinal sub-epithelial myofibroblasts that tightly control their function. It has been postulated that mutations within these adult colonic stem cells may induce neoplastic changes. Such cells can then dissociate from the epithelium and travel into the mesenchyme and thus form invasive cancers. This theory is based on the observation that within a colon cancer, less than 1% of the neoplastic cells have the ability to regenerate the tumour. It is this group of cells that exhibits characteristics of colonic stem cells. Although anti-neoplastic agents can induce remissions by inhibiting cell division, the stem cells appear to be remarkably resistant to both standard chemotherapy and radiotherapy. These stem cells may therefore persist after treatment and form the nucleus for cancer recurrence. Hence, future treatment modalities should focus specifically on controlling the cancer stem cells. In this review, we discuss the biology of normal and malignant colonic stem cells.

  20. Smoking History Predicts Sensitivity to PARP Inhibitor Veliparib in Patients with Advanced Non-Small Cell Lung Cancer.

    Science.gov (United States)

    Reck, Martin; Blais, Normand; Juhasz, Erzsebet; Gorbunova, Vera; Jones, C Michael; Urban, Laszlo; Orlov, Sergey; Barlesi, Fabrice; Kio, Ebenezer; Keilholz, Ulrich; Qin, Qin; Qian, Jiang; Nickner, Caroline; Dziubinski, Juliann; Xiong, Hao; Mittapalli, Rajendar K; Dunbar, Martin; Ansell, Peter; He, Lei; McKee, Mark; Giranda, Vincent; Ramalingam, Suresh S

    2017-07-01

    Tobacco-related NSCLC is associated with reduced survival and greater genomic instability. Veliparib, a potent poly(adenosine diphosphate-ribose) polymerase inhibitor, augments platinum-induced DNA damage. A phase 2 trial of untreated advanced NSCLC showed a trend for improved outcomes (hazard ratio [HR] = 0.80, 95% confidence interval: 0.54-1.18, p = 0.27 for overall survival and HR = 0.72, 95% CI: 0.45-1.15, p = 0.17 for progression-free survival) when veliparib was added to carboplatin/paclitaxel. Here we report an exploratory analysis by smoking history. Patients were randomized 2:1 to receive carboplatin/paclitaxel with veliparib, 120 mg (n = 105), or placebo (n = 53). Patients were stratified by histologic subtype and smoking history (recent smokers [n = 95], former smokers [n = 42], and never-smokers [n = 21]). Plasma cotinine level was measured as a chemical index of smoking. Mutation status was assessed by whole exome sequencing (n = 38). Smoking history, histologic subtype, age, Eastern Cooperative Oncology Group performance status, sex, and geographic region predicted veliparib benefit in univariate analyses. In multivariate analysis, history of recent smoking was most predictive for veliparib benefit. Recent smokers treated with veliparib derived significantly greater progression-free survival and overall survival benefits (HR = 0.38 [p Smoking history predicted for efficacy with a veliparib-chemotherapy combination; toxicity was acceptable regardless of smoking history. A prespecified analysis of recent smokers is planned for ongoing phase 3 studies of veliparib in NSCLC. Copyright © 2017 International Association for the Study of Lung Cancer. Published by Elsevier Inc. All rights reserved.

  1. Stages of Renal Cell Cancer

    Science.gov (United States)

    ... Tumors Treatment Genetics of Kidney Cancer Research Renal Cell Cancer Treatment (PDQ®)–Patient Version General Information About Renal Cell Cancer Go to Health Professional Version Key Points Renal ...

  2. The Fanconi anemia pathway sensitizes to DNA alkylating agents by inducing JNK-p53-dependent mitochondrial apoptosis in breast cancer cells.

    Science.gov (United States)

    Zhao, Lin; Li, Yanlin; He, Miao; Song, Zhiguo; Lin, Shu; Yu, Zhaojin; Bai, Xuefeng; Wang, Enhua; Wei, Minjie

    2014-07-01

    The Fanconi anemia/BRCA (FA/BRCA) DNA damage repair pathway plays a pivotal role in the cellular response to DNA alkylating agents and greatly influences drug response in cancer treatment. However, the molecular mechanisms underlying the FA/BRCA pathway reversed resistance have received limited attention. In the present study, we investigated the effect of Fanconi anemia complementation group F protein (FANCF), a critical factor of the FA/BRCA pathway, on cancer cell apoptosis induced by DNA alkylating agents such as mitomycin c (MMC). We found that FANCF shRNA potentiated MMC-induced cytotoxicity and apoptosis in MCF-7 and MDA-MB-231 breast cancer cells. At a mechanistic level, FANCF shRNA downregulated the anti-apoptotic protein Bcl-2 and upregulated the pro-apoptotic protein Bax, accompanied by release of cyt-c and smac into the cytosol in MMC-treated cells. Furthermore, activation of caspase-3 and -9, other than caspase-8, cleavage of poly(ADP ribose) polymerase (PARP), and a decrease of mitochondrial membrane potential (MMP) indicated that involvement of the mitochondrial apoptotic pathway in FANCF silencing of MMC-treated breast cancer cells. A decrease in IAP family proteins XIAP and survivin were also observed following FANCF silencing in MMC-treated breast cancer cells. Notably, FANCF shRNA was able to increase p53 levels through activation of the JNK pathway in MMC-treated breast cancer cells. Furthermore, p53 inhibition using pifithrin-α abolished the induction of caspase-3 and PARP by FANCF shRNA and MMC, indicating that MMC-induced apoptosis is substantially enhanced by FANCF shRNA via p53-dependent mechanisms. To our knowledge, we provide new evidence for the potential application of FANCF as a chemosensitizer in breast cancer therapy.

  3. Isolation of two chloroethylnitrosourea-sensitive Chinese hamster cell lines

    International Nuclear Information System (INIS)

    Hata, H.; Numata, M.; Tohda, H.; Yasui, A.; Oikawa, A.

    1991-01-01

    1-[(4-Amino-2-methylpyrimidin-5-yl)methyl]-3-(2-chloroethyl)-3- nitrosourea hydrochloride (ACNU), a cancer chemotherapeutic bifunctional alkylating agent, causes chloroethylation of DNA and subsequent DNA strand cross-linking through an ethylene bridge. We isolated and characterized two ACNU-sensitive mutants from mutagenized Chinese hamster ovary cells and found them to be new drug-sensitive recessive Chinese hamster mutants. Both mutants were sensitive to various monofunctional alkylating agents in a way similar to that of the parental cell lines CHO9. One mutant (UVS1) was cross-sensitive to UV and complemented the UV sensitivity of all Chinese hamster cell lines of 7 established complementation groups. Since UV-induced unscheduled DNA synthesis was very low, a new locus related to excision repair is thought to be defective in this cell line. Another ACNU-sensitive mutant, CNU1, was slightly more sensitive to UV than the parent cell line. CNU1 was cross-sensitive to 1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea and slightly more sensitive to mitomycin C. No increased accumulation of ACNU and a low level of UV-induced unscheduled DNA synthesis in this cell as compared with the parental cell line suggest that there is abnormality in a repair response of this mutant cell to some types of DNA cross-links

  4. d -Limonene sensitizes docetaxel-induced cytotoxicity in human prostate cancer cells: Generation of reactive oxygen species and induction of apoptosis

    Directory of Open Access Journals (Sweden)

    Rabi Thangaiyan

    2009-01-01

    Full Text Available Background: Clinical trials have shown that docetaxel combined with other novel agents can improve the survival of androgen-independent prostate cancer patients. d -Limonene, a non-nutrient dietary component, has been found to inhibit various cancer cell growths without toxicity. We sought to characterize whether a non-toxic dose of d -limonene may enhance tumor response to docetaxel in an in vitro model of metastatic prostate cancer. Materials and Methods: Human prostate carcinoma DU-145 and normal prostate epithelial PZ-HPV-7 cells were treated with various concentrations of d -limonene, docetaxel or a combination of both, and cell viability was determined by MTT assay. Intracellular reactive oxygen species (ROS, reduced glutathione (GSH and caspase activity were measured. Apoptosis and apoptosis-related proteins were studied by enzyme-linked immunosorbent assay and Western blotting, respectively. Results: d -Limonene and docetaxel in combination significantly enhanced the cytotoxicity to DU-145 cells than PZ-HPV-7 cells. Exposure of DU-145 cells to a combined d -limonene and docetaxel resulted in higher ROS generation, depletion of GSH, accompanied by increased caspase activity than docetaxel alone. It also triggered a series of effects involving cytochrome c , cleavages of caspase-9, 3 and poly (ADP-ribose polymerase, and a shift in Bad:Bcl-xL ratio in favor of apoptosis. Apoptotic effect was significantly blocked on pretreatment with N -acetylcystein, indicating that antitumor effect is initiated by ROS generation, and caspase cascades contribute to the cell death. Conclusion: Our results show, for the first time, that d -limonene enhanced the antitumor effect of docetaxel against prostate cancer cells without being toxic to normal prostate epithelial cells. The combined beneficial effect could be through the modulation of proteins involved in mitochondrial pathway of apoptosis. d -Limonene could be used as a potent non-toxic agent to

  5. Fingerprints in cancer cells

    International Nuclear Information System (INIS)

    Servomaa, K.

    1994-01-01

    Gene research has shown that factors causing cancer, or carcinogens, may leave marks typical of each particular carcinogen (fingerprints) in the genotype of the cell. Radiation, for instance, may leave such fingerprints in a cancer cell. In particular, the discovery of a gene called p53 has yielded much new information on fingerprints. It has been discovered, for example, that toxic fungus and UV-radiation each leave fingerprints in the p53 gene. Based on the detection of fingerprints, it may be possible in the future to tell a cancer patient what factor had trigged the maglinancy

  6. 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.

  7. Acquired EGFR L718V mutation mediates resistance to osimertinib in non-small cell lung cancer but retains sensitivity to afatinib.

    Science.gov (United States)

    Liu, Yutao; Li, Yan; Ou, Qiuxiang; Wu, Xue; Wang, Xiaonan; Shao, Yang W; Ying, Jianming

    2018-04-01

    Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) are promising targeted therapies for EGFR-mutated non-small-cell lung cancer (NSCLC) patients. However, acquired resistance inevitably develops. Comprehensive and dynamic companion genomic diagnosis can gain insights into underlying resistance mechanisms, thereby help oncologists and patients to make informed decision on the potential benefit of the treatment. A 67-year-old male who was initially diagnosed of EGFR L858R-mediated NSCLC received multiple lines of chemotherapy and EGFR TKI therapies after surgery. The EGFR mutational status of individual metastatic lesion was determined by genetic testing of the tumor tissue biopsies using next generation sequencing (NGS) throughout the patient's clinical course. An acquired potentially drug-resistant EGFR mutation was functionally validated in vitro and its sensitivity to different EGFR TKIs was assessed simultaneously. We have identified distinct resistance mechanisms to EGFR blockade in different metastatic lung lesions. Acquired EGFR T790M was first detected that leads to the resistance to the gefitinib treatment. Consequently, osimertinib was administrated and the response lasted until disease progressed. We identified a newly acquired EGFR L718V mutation in one lesion in conjunction with L858R, but not T790M, which showed stable disease on the following erlotinib treatment, while EGFR C797S together with L858R/T790M was detected in the other lesion that continuously progressed. In vitro functional studies demonstrated that EGFR-L858R/L718V confers resistance to osimertinib, but retains sensitivity to the second generation TKI afatinib. We reported that distinct resistance mechanisms could arise in different metastases within the same patient in response to EGFR blockade. We also demonstrated in vitro that EGFR L718V mutation mediates resistance to osimertinib, but retains sensitivity to afatinib. We evidenced that dynamic companion genomic

  8. Harnessing Connectivity in a Large-Scale Small-Molecule Sensitivity Dataset | Office of Cancer Genomics

    Science.gov (United States)

    Identifying genetic alterations that prime a cancer cell to respond to a particular therapeutic agent can facilitate the development of precision cancer medicines. Cancer cell-line (CCL) profiling of small-molecule sensitivity has emerged as an unbiased method to assess the relationships between genetic or cellular features of CCLs and small-molecule response. Here, we developed annotated cluster multidimensional enrichment analysis to explore the associations between groups of small molecules and groups of CCLs in a new, quantitative sensitivity dataset.

  9. 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.

  10. Extragonadal Germ Cell Cancer (EGC)

    Science.gov (United States)

    The Testicular Cancer Resource Center Extragonadal Germ Cell Cancer (EGC) 95% of all testicular tumors are germ cell tumors. That is, the tumors originate in the sperm forming cells in the testicles ( ...

  11. Hypoxic human cancer cells are sensitized to BH-3 mimetic–induced apoptosis via downregulation of the Bcl-2 protein Mcl-1

    Science.gov (United States)

    Harrison, Luke R.E.; Micha, Dimitra; Brandenburg, Martin; Simpson, Kathryn L.; Morrow, Christopher J.; Denneny, Olive; Hodgkinson, Cassandra; Yunus, Zaira; Dempsey, Clare; Roberts, Darren; Blackhall, Fiona; Makin, Guy; Dive, Caroline

    2011-01-01

    Solid tumors contain hypoxic regions in which cancer cells are often resistant to chemotherapy-induced apoptotic cell death. Therapeutic strategies that specifically target hypoxic cells and promote apoptosis are particularly appealing, as few normal tissues experience hypoxia. We have found that the compound ABT-737, a Bcl-2 homology domain 3 (BH-3) mimetic, promotes apoptotic cell death in human colorectal carcinoma and small cell lung cancer cell lines exposed to hypoxia. This hypoxic induction of apoptosis was mediated through downregulation of myeloid cell leukemia sequence 1 (Mcl-1), a Bcl-2 family protein that serves as a biomarker for ABT-737 resistance. Downregulation of Mcl-1 in hypoxia was independent of hypoxia-inducible factor 1 (HIF-1) activity and was consistent with decreased global protein translation. In addition, ABT-737 induced apoptosis deep within tumor spheroids, consistent with an optimal hypoxic oxygen tension being necessary to promote ABT-737–induced cell death. Tumor xenografts in ABT-737–treated mice also displayed significantly more apoptotic cells within hypoxic regions relative to normoxic regions. Synergies between ABT-737 and other cytotoxic drugs were maintained in hypoxia, suggesting that this drug may be useful in combination with chemotherapeutic agents. Taken together, these findings suggest that Mcl-1–sparing BH-3 mimetics may induce apoptosis in hypoxic tumor cells that are resistant to other chemotherapeutic agents and may have a role in combinatorial chemotherapeutic regimens for treatment of solid tumors. PMID:21393866

  12. Cancer stem cells revisited

    NARCIS (Netherlands)

    Batlle, Eduard; Clevers, Hans

    2017-01-01

    The cancer stem cell (CSC) concept was proposed four decades ago, and states that tumor growth, analogous to the renewal of healthy tissues, is fueled by small numbers of dedicated stem cells. It has gradually become clear that many tumors harbor CSCs in dedicated niches, and yet their

  13. Radiation sensitizations at DNA-level by chemical and biological agents. Coordinated programme on improvement of radiotherapy of cancer using modifiers of radiosensitivity of cells

    International Nuclear Information System (INIS)

    Altmann, H.

    1982-01-01

    Radiation sensitization by chemical agents at DNA level is discussed. Procaine, Halothan and Metronidazole showed no significant effect on unscheduled DNA synthesis (UDS) in mouse spleen cells, investigated by autoradiography and no effect on rejoining of DNA single strand breaks after gamma or UV irradiation. Oxyphenbutazon and prednisolone reduced the replicative DNA synthesis in vitro and in vivo but there was only little effect on DNA repair in the in vivo experiments. These two substances showed also a small reduction in poly(ADP-ribose) synthesis (PAR synthesis). 5-methoxypsoralen (5-MOP) and 8-methoxypsoralen (8-MOP) in combination with UV irradiation showed that 5-MOP was more toxic than mutagen, but induced much less DNA crosslinks than 8-MOP. Autoradiographic studies of radiation sensitization by biological agents showed significant inhibition of UDS in Yoshida tumor cells after acute mycoplasma infection in rats. Nucleoid sedimentation studies showed only in the case of Yoshida tumor cells after mycoplasma infection a dramatic effect in the sedimentation behaviour. Sensitization of cells by changing chromatin structure was also studied. Benzamide, 3-NH 2 -benzamide, 3-Methoxybenzamide, Spermine, Theophyllin and Caffeine were tested in different concentrations on replicative DNA synthesis, UDS after UV irradiation and PAR synthesis Chinese hamster ovary cells. 5-Methoxybenzamide was the strongest sensitizer and inhibitor of the PAR synthesis, and was used in further experiments. Results of KFA Juelich on sensitization of a mamma-adenocarcinoma EO 771 on C57 B1 mice are given. Replicative DNA synthesis, DNA repair and PAR synthesis were compared in spleen cells and adenocarcinoma cells after treatment with 5-Methoxybenzamide. An inhibitory effect on UDS could be shown only in adenocarcinoma cells but not in the mice spleen cells

  14. Understanding drugs in breast cancer through drug sensitivity screening.

    Science.gov (United States)

    Uhr, Katharina; Prager-van der Smissen, Wendy J C; Heine, Anouk A J; Ozturk, Bahar; Smid, Marcel; Göhlmann, Hinrich W H; Jager, Agnes; Foekens, John A; Martens, John W M

    2015-01-01

    With substantial numbers of breast tumors showing or acquiring treatment resistance, it is of utmost importance to develop new agents for the treatment of the disease, to know their effectiveness against breast cancer and to understand their relationships with other drugs to best assign the right drug to the right patient. To achieve this goal drug screenings on breast cancer cell lines are a promising approach. In this study a large-scale drug screening of 37 compounds was performed on a panel of 42 breast cancer cell lines representing the main breast cancer subtypes. Clustering, correlation and pathway analyses were used for data analysis. We found that compounds with a related mechanism of action had correlated IC50 values and thus grouped together when the cell lines were hierarchically clustered based on IC50 values. In total we found six clusters of drugs of which five consisted of drugs with related mode of action and one cluster with two drugs not previously connected. In total, 25 correlated and four anti-correlated drug sensitivities were revealed of which only one drug, Sirolimus, showed significantly lower IC50 values in the luminal/ERBB2 breast cancer subtype. We found expected interactions but also discovered new relationships between drugs which might have implications for cancer treatment regimens.

  15. Sensitivity to Fas-mediated apoptosis in high-risk HPV-positive human cervical cancer cells : Relationship with Fas, caspase-8, and Bid

    NARCIS (Netherlands)

    Hougardy, BMT; van der Zee, AGJ; van den Heuvel, FAJ; Timmer, T; de Vries, EGE; de Jong, S

    Objective. Binding of Fas ligand or agonistic anti-Fas antibody to the death receptor Fas can activate a caspase-cascade resulting in apoptosis. In the present study, the functionality of the Fas pathway was studied in human cervical cancer cells with different HPV and p53 status. Methods. HeLa

  16. The small-molecule Bcl-2 inhibitor HA14-1 sensitizes cervical cancer cells, but not normal fibroblasts, to heavy-ion radiation

    International Nuclear Information System (INIS)

    Hamada, Nobuyuki; Kataoka, Keiko; Sora, Sakura; Hara, Takamitsu; Omura-Minamisawa, Motoko; Funayama, Tomoo; Sakashita, Tetsuya; Nakano, Takashi; Kobayashi, Yasuhiko

    2008-01-01

    This is the first study to demonstrate that the small-molecule Bcl-2 inhibitor HA14-1 renders human cervical cancer cells and their Bcl-2 overexpressing radioresistant counterparts, but not normal fibroblasts, more susceptible to heavy ions. Thus, Bcl-2 may be an attractive target for improving the efficacy of heavy-ion therapy

  17. Newly established tumourigenic primary human colon cancer cell lines are sensitive to TRAIL-induced apoptosis in vitro and in vivo

    Czech Academy of Sciences Publication Activity Database

    Oikonomou, E.; Kothonidis, K.; Zografos, G.; Nasioulas, G.; Anděra, Ladislav; Pintzas, A.

    2007-01-01

    Roč. 97, č. 12 (2007), s. 73-84 ISSN 0007-0920 Grant - others:EU(XE) LSHC-CT-2006-037278 Institutional research plan: CEZ:AV0Z50520514 Keywords : TRAIL * apoptosis * colon cancer cell lines Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 4.635, year: 2007

  18. How far is cancer cured by radiation sensitization?

    International Nuclear Information System (INIS)

    Ando, Koichi; Sasaki, Takehito; Ikeda, Hiroshi

    1990-01-01

    Some types of cancer are not cured by radiation alone in view of histology, location, and size. In facing so-called radioresistant cancer, antineoplastic agents, hypoxic cell sensitizers, biological response modifiers, or hyperthermia are used in combination with radiation, with the aim of cancer cure. First of all, this chapter discusses the subject of 'what is tumor cure by radiation therapy'. Current conditions of the aforementioned combined modalities and the future perspectives are presented. The following subjects are covered: (1) tumor control - significance of the number of stem cells; (2) biological evaluation of chemo-radiotherapy with cisplatin; (3) clinical results and experience with combination of radiotherapy and radiosensitizers; (4) radiosensitization with hypoxic cell radiosensitizers - present status (5) hypoxic cell radiosensitizers - present status and problems from the viewpoint of clinical radiotherapy; (6) thermal radiosensitization in vitro and its implications for radiotherapy; (7) clinical assessment of thermoradiotherapy for breast cancer and cancer of the urinary bladder; (8) interactions of radiation and biological response modifiers in the treatment of malignant tumor; (9) improvement in the effects of radiation therapy with biological response modifiers. (N.K.)

  19. 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.

  20. 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. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  1. Cancer Stem Cells in Pancreatic Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Bao, Qi; Zhao, Yue; Renner, Andrea; Niess, Hanno; Seeliger, Hendrik; Jauch, Karl-Walter; Bruns, Christiane J., E-mail: christiane.bruns@med.uni-muenchen.de [Department of Surgery, Ludwig Maximilian University of Munich, Klinikum Grosshadern, Marchioninistr. 15, D-81377, Munich (Germany)

    2010-08-19

    Pancreatic cancer is an aggressive malignant solid tumor well-known by early metastasis, local invasion, resistance to standard chemo- and radiotherapy and poor prognosis. Increasing evidence indicates that pancreatic cancer is initiated and propagated by cancer stem cells (CSCs). Here we review the current research results regarding CSCs in pancreatic cancer and discuss the different markers identifying pancreatic CSCs. This review will focus on metastasis, microRNA regulation and anti-CSC therapy in pancreatic cancer.

  2. Cancer Stem Cells in Pancreatic Cancer

    Science.gov (United States)

    Bao, Qi; Zhao, Yue; Renner, Andrea; Niess, Hanno; Seeliger, Hendrik; Jauch, Karl-Walter; Bruns, Christiane J.

    2010-01-01

    Pancreatic cancer is an aggressive malignant solid tumor well-known by early metastasis, local invasion, resistance to standard chemo- and radiotherapy and poor prognosis. Increasing evidence indicates that pancreatic cancer is initiated and propagated by cancer stem cells (CSCs). Here we review the current research results regarding CSCs in pancreatic cancer and discuss the different markers identifying pancreatic CSCs. This review will focus on metastasis, microRNA regulation and anti-CSC therapy in pancreatic cancer. PMID:24281178

  3. Cancer Stem Cells in Pancreatic Cancer

    Directory of Open Access Journals (Sweden)

    Karl-Walter Jauch

    2010-08-01

    Full Text Available Pancreatic cancer is an aggressive malignant solid tumor well-known by early metastasis, local invasion, resistance to standard chemo- and radiotherapy and poor prognosis. Increasing evidence indicates that pancreatic cancer is initiated and propagated by cancer stem cells (CSCs. Here we review the current research results regarding CSCs in pancreatic cancer and discuss the different markers identifying pancreatic CSCs. This review will focus on metastasis, microRNA regulation and anti-CSC therapy in pancreatic cancer.

  4. Comparative Study of 17-AAG and NVP-AUY922 in Pancreatic and Colorectal Cancer Cells: Are There Common Determinants of Sensitivity?

    Science.gov (United States)

    Mayor-López, Leticia; Tristante, Elena; Carballo-Santana, Mar; Carrasco-García, Estefanía; Grasso, Silvina; García-Morales, Pilar; Saceda, Miguel; Luján, Juan; García-Solano, José; Carballo, Fernando; de Torre, Carlos; Martínez-Lacaci, Isabel

    2014-10-01

    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 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.

  5. 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.

  6. 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.

  7. 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.

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

    Science.gov (United States)

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

    2016-03-01

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

  9. The proteasome inhibitor MG-132 sensitizes PC-3 prostate cancer cells to ionizing radiation by a DNA-PK-independent mechanism

    International Nuclear Information System (INIS)

    Pajonk, Frank; Ophoven, Arndt van; Weissenberger, Christian; McBride, William H

    2005-01-01

    By modulating the expression levels of specific signal transduction molecules, the 26S proteasome plays a central role in determining cell cycle progression or arrest and cell survival or death in response to stress stimuli, including ionizing radiation. Inhibition of proteasome function by specific drugs results in cell cycle arrest, apoptosis and radiosensitization of many cancer cell lines. This study investigates whether there is also a concomitant increase in cellular radiosensitivity if proteasome inhibition occurs only transiently before radiation. Further, since proteasome inhibition has been shown to activate caspase-3, which is involved in apoptosis, and caspase-3 can cleave DNA-PKcs, which is involved in DNA-double strand repair, the hypothesis was tested that caspase-3 activation was essential for both apoptosis and radiosensitization following proteasome inhibition. Prostate carcinoma PC-3 cells were treated with the reversible proteasome inhibitor MG-132. Cell cycle distribution, apoptosis, caspase-3 activity, DNA-PKcs protein levels and DNA-PK activity were monitored. Radiosensitivity was assessed using a clonogenic assay. Inhibition of proteasome function caused cell cycle arrest and apoptosis but this did not involve early activation of caspase-3. Short-time inhibition of proteasome function also caused radiosensitization but this did not involve a decrease in DNA-PKcs protein levels or DNA-PK activity. We conclude that caspase-dependent cleavage of DNA-PKcs during apoptosis does not contribute to the radiosensitizing effects of MG-132

  10. Prognostic role of sensitive-to-apoptosis gene expression in rectal cancer

    DEFF Research Database (Denmark)

    Ozden, Sevgi A; Ozyurt, Hazan; Ozgen, Zerrin

    2011-01-01

    To investigate the association between prognosis of rectal cancer treated with chemoradiotherapy (CRT) and expression of sensitive-to-apoptosis (SAG), B-cell lymphoma-extra large (Bcl-X(L)) and Bcl-2 homologous antagonist/killer (Bak).......To investigate the association between prognosis of rectal cancer treated with chemoradiotherapy (CRT) and expression of sensitive-to-apoptosis (SAG), B-cell lymphoma-extra large (Bcl-X(L)) and Bcl-2 homologous antagonist/killer (Bak)....

  11. New avenues in hypoxic cell sensitization

    International Nuclear Information System (INIS)

    Huilgol, N.G.; Chatterjee, N.A.; Singh, B.B.

    1995-01-01

    Hypoxic cells in tumors represent a population of cells that are resistant to radiotherapy. Bio-reductive agents like RSU 1069, RBU 6145 and EOg and vasoactive drugs in conjunction with hypoxic cell sensitizers are being evaluated as hypoxic cell cytotoxins. Chlorpromazine a membrane active drug and AK-2123- a nitrotriazole with a potential to deplete intracellular thiols induced vasoconstriction and sensitize hypoxic cells have stretched the boundaries of innovation. A preliminary experience with these drugs is discussed. 8 refs., 2 tabs., 2 figs

  12. Electrochemistry and dye-sensitized solar cells

    Czech Academy of Sciences Publication Activity Database

    Kavan, Ladislav

    2017-01-01

    Roč. 2, č. 1 (2017), s. 88-98 ISSN 2451-9103 R&D Projects: GA ČR GA13-07724S Institutional support: RVO:61388955 Keywords : electrochemistry * dye-sensitized cells * photoelectrode Subject RIV: CG - Electrochemistry OBOR OECD: Electrochemistry (dry cells, batteries, fuel cells, corrosion metals, electrolysis)

  13. New Treatment Option for Young Women with Hormone-Sensitive Breast Cancer

    Science.gov (United States)

    ... Common Cancer Types Recurrent Cancer Common Cancer Types Bladder Cancer Breast Cancer Colorectal Cancer Kidney (Renal Cell) Cancer ... breast cancer, defined as estrogen and/or progesterone receptor-positive breast cancer, represents 79 percent of breast ...

  14. Radiation sensitization studies by silymarin on HCT-15 cells

    International Nuclear Information System (INIS)

    Lal, Mitu; Gupta, Damodar; Arora, R.

    2014-01-01

    Radiotherapy has been widely used for treatment of human cancers. However, cancer cells develop radioresistant phenotypes following multiple exposures to the treatment agent that decrease the efficacy of radiotherapy. Here it was investigated that the radiation sensitization effects of silymarin found in colon cancer. The aim of this study was to investigate mechanisms involved in radiation sensitization growth inhibitory effect of silymarin in combination with radiation, in Human colon carcinoma (HCT-15). The human colon carcinoma was utilized and SRB-assay was performed to study anti-proliferative effect of silymarin in combination with gamma radiation (2 Gy) appropriate radiation dose was optimized and confirmed by clonogenic assay. Microscopic analysis was done by staining with Hoechst-33342, DAPI, Propidium iodide to confirm the presence of apoptosis. Nitric oxide production, changes in lipid peroxidation, Cell cycle analysis were carried out and mitochondrial membrane potential was measured by uptake of cationic dye JC-1 by using flow cytometer. Silymarin in combination with radiation (2 Gy) inhibited 70% ± 5% population growth of HCT-15 cells in time and dose dependent manner. Pre treatment of cells with silymarin for 30 min before radiation was found to be most effective for radiation sensitization. There was 25% increase in levels of nitric oxide as compare to control, whereas 2.5 fold change in lipid peroxidation with respect to control. IR-induced apoptosis in HCT-15 cell line was significantly enhanced by silymarin, as reflected by viability, DNA fragmentation, and mitochondrial dysfunction. Additionally, silymarin in combination with IR is found to be effective in sensitization of HCT-15 cells. In vivo studies on development of tumor and sensitization aspects needs to done in future. (author)

  15. The effect of icotinib combined with chemotherapy in untreated non-small-cell lung cancer that harbored EGFR-sensitive mutations in a real-life setting: a retrospective analysis

    Directory of Open Access Journals (Sweden)

    Wang LL

    2018-04-01

    Full Text Available Lulu Wang, Yan Li, Luchun Li, Zhijuan Wu, Dan Yang, Huiwen Ma, Donglin Wang Oncology Department, Chongqing University Cancer Hospital & Chongqing Cancer Institute & Chongqing Cancer Hospital, Shapingba District, Chongqing, China Purpose: This study was conducted to compare the efficacy of a combination of icotinib and chemotherapy with icotinib or chemotherapy alone in untreated non-small cell lung cancer (NSCLC patients harboring epidermal growth factor receptor (EGFR-sensitive mutations and to analyze the curative effect of different treatments on different genetic mutations (EGFR 19 exon deletion and L858R mutation in a real-life setting. Patients and methods: One hundred ninety-one patients were studied in this retrospective analysis from January 2013 to December 2015. The baseline characteristics, curative effects and adverse events of patients were analyzed. The primary endpoint was progression free survival (PFS. Results: Longer PFS and overall survival (OS, and better objective response rate (ORR were observed in the combination group compared to icotinib or chemotherapy along. For patients with an EGFR 19 exon deletion, the PFS, OS, and ORR in the combination group were superior to those in the icotinib or chemotherapy group. For the patients with the EGFR L858R mutation, better PFS and ORR were observed in the combination group, but OS was not obviously prolonged. Grade 3 or 4 adverse events were most commonly reported with combination therapy or chemotherapy alone. No possible drug-related interstitial lung disease or of drug related deaths occurred. Conclusion: The combination of icotinib and chemotherapy in patients with untreated NSCLC harboring sensitive EGFR mutations resulted in improved PFS and OS,especially in those who harbored the EGFR exon 19 deletion. Keywords: non-small-cell lung cancer, EGFR-TKI, icotinib, chemotherapy, first-line treatment

  16. Pyramidatine (Z88) Sensitizes Vincristine-Resistant Human Oral Cancer (KB/VCR) Cells to Chemotherapeutic Agents by Inhibition of P-glycoprotein.

    Science.gov (United States)

    Liu, Zulong; Zhu, Hengrui; Qu, Shijin; Tang, Lisha; Cao, Lihuan; Yu, Wenbo; Yang, Xianmei; Jiang, Songmin; Zhu, Dayuan; Tan, Changheng; Yu, Long

    2018-01-01

    Multi-drug resistance (MDR) remains a major impediment in cancer therapy. A major goal for scientists is to discover more effective compounds that are able to circumvent MDR and simultaneously have minimal adverse side effects. In the present study, we aim to determine the anti-MDR effects of pyramidatine (Z88), a cinnamic acid-derived bisamide compound isolated from the leaves of Aglaia perviridis, on KB/VCR (vincristineresistant human oral cancer cells) and MCF-7/ADR (adriamycin-resistant human breast adenocarcinoma) cells. Cell viability and average resistant fold (RF) of Z88 were examined by Cell Counting Kit-8 (CCK-8) assay. Flow cytometry, western blot, RT-PCR, Rhodamine 123 accumulation assay and P-glycoprotein (P-gp) ATPase assay were used to demonstrate the anti-MDR activity and mechanism of Z88. The average RF of Z88 is 0.09 and 0.51 in KB/VCR and MCF-7/ADR cells. A CCK-8 assay showed that Z88 could enhance the cytotoxicity of VCR toward KB/VCR cells. A FACS analysis revealed that Z88 could enhance the VCR-induced apoptosis as well as G2/M arrest in a dose-dependent manner in KB/VCR cells. Western blot results showed that the expression levels of PARP, Bax, and cyclin B1 all increased after treatment with 0.2 µmol/L (µM) of VCR combined with 10 µM of Z88 for 24 h in KB/VCR cells. Z88 also could enhance the accumulation of rhodamine 123. Further studies showed that Z88 could inhibit the verapamil stimulated Pgp ATPase activity. Additionally, qPCR detection and western blot assays revealed that Z88 could decrease the expression of P-gp at both RNA and protein level. Z88 exerted potent anti-MDR activity in vitro and its mechanisms are associated with dualinhibition of the function and expression of P-gp. These findings encourage efforts to develop more effective reversal agents to circumvent MDR based on Z88. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  17. Inhibition of heat-shock protein 90 sensitizes liver cancer stem-like cells to magnetic hyperthermia and enhances anti-tumor effect on hepatocellular carcinoma-burdened nude mice

    Science.gov (United States)

    Yang, Rui; Tang, Qiusha; Miao, Fengqin; An, Yanli; Li, Mengfei; Han, Yong; Wang, Xihui; Wang, Juan; Liu, Peidang; Chen, Rong

    2015-01-01

    Purpose To explore the thermoresistance and expression of heat-shock protein 90 (HSP90) in magnetic hyperthermia-treated human liver cancer stem-like cells (LCSCs) and the effects of a heat-shock protein HSP90 inhibitor 17-allylamino-17-demethoxgeldanamycin (17-AAG) on hepatocellular carcinoma-burdened nude mice. Methods CD90+ LCSCs were isolated by magnetic-activated cell sorting from BEL-7404. Spheroid formation, proliferation, differentiation, drug resistance, and tumor formation assays were performed to identify stem cell characteristics. CD90-targeted thermosensitive magnetoliposomes (TMs)-encapsulated 17-AAG (CD90@17-AAG/TMs) was prepared by reverse-phase evaporation and its characteristics were studied. Heat tolerance in CD90+ LCSCs and the effect of CD90@17-AAG/TMs-mediated heat sensitivity were examined in vitro and in vivo. Results CD90+ LCSCs showed significant stem cell-like properties. The 17-AAG/TMs were successfully prepared and were spherical in shape with an average size of 128.9±7.7 nm. When exposed to magnetic hyperthermia, HSP90 was up-regulated in CD90+ LCSCs. CD90@17-AAG/TMs inhibited the activity of HSP90 and increased the sensitivity of CD90+ LCSCs to magnetic hyperthermia. Conclusion The inhibition of HSP90 could sensitize CD90+ LCSCs to magnetic hyperthermia and enhance its anti-tumor effects in vitro and in vivo. PMID:26677324

  18. Dye-sensitized solar cells based on purple corn sensitizers

    International Nuclear Information System (INIS)

    Phinjaturus, Kawin; Maiaugree, Wasan; Suriharn, Bhalang; Pimanpaeng, Samuk; Amornkitbamrung, Vittaya; Swatsitang, Ekaphan

    2016-01-01

    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.

  19. 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.

  20. Heat shock protein 90 chaperone complex inhibitor enhanced radiosensitivity through modification of response to hormone and degradation of androgen receptor in hormone sensitive prostate cancer cell line

    International Nuclear Information System (INIS)

    Mitsuhashi, N.; Harashima, K.; Akimoto, T.

    2003-01-01

    It is easily speculated that androgen or androgen deprivation affects proliferative activity or radiosensitivity, but there has been enough information how androgen or androgen deprivation influences the response to radiation. In this setting, the effect of dihydrotestosterone (DHT) on cellular growth and radiosensitivity was examined in hormone-responsive human prostate cancer cell line (LnCap). The binding of androgen receptor (AR) with heat shock protein 90 (Hsp90) plays an important role in stability of the function of receptor. It was, therefore, examined how Hsp90 chaperone complex inhibitor modified the effect of DHT on radiosensitivity in addition to the effect of DHT, especially focusing on AR and its downstream signal transduction pathways. Hydroxy-flutamide (OH-flutamide) was also used to confirm the effect of activation of AR on radiosensitivity because AR of LnCap has a point mutation, leading to activation of AR caused by the binding of OH-flutamide. Radicicol was used as a Hsp90 chaperone complex inhibitor, and incubated with cells at a concentration of 500 nM. Radicicol was incubated with cells for 9 h, and cells were irradiated 1 h after the start of incubation. DHT and OH-flutamide were incubated with cells until staining. DHT or OH-flutamide resulted in stimulation of cellular growth in contrast to inhibition of cellular growth caused by higher concentrations, so that we adopted 1 nM as a concentration of DHT and 1μM as a concentration of OH-flutamide. DHT or OH-flutamide in combination with radiation resulted in slight decrease in radiosensitivity compared with radiation alone. Radicicol at a concentration of 500 nM in combination with DHT or OH-flutamide abolished decrease in radiosensitivity caused by DHT or OH-flutamide. In terms of the expression of AR, radicicol in combination with radiation and/or DHT, OH-flutamide induced degradation of AR. In consistent with degradation of AR, the expression of prostate specific antigen (PSA) decreased

  1. 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.

  2. A phase I study of paclitaxel as a radiation sensitizer for the treatment of non-small cell lung cancer and mesothelioma

    International Nuclear Information System (INIS)

    Herscher, L.; Hahn, S.; Pass, H.; Temeck, B.; Goldspiel, B.; Cook, J.; Mitchell, J.B.; Liebmann, J.

    1995-01-01

    Purpose/Objective Paclitaxel exposure of cancer cells in vitro results in a G 2 /M block in the cell cycle. Paclitaxel also has independent activity against a wide variety of tumors. We report here a phase I study of patients with non-small cell lung cancer and malignant pleural mesothelioma treated with radiation therapy and concurrent paclitaxel. Objectives were to determine the maximum tolerated dose (MTD) of paclitaxel when delivered as a 5-day continuous infusion with concurrent radiotherapy, to assess tumor response and toxicity, and to evaluate the biological effects of paclitaxel in tumor biopsy specimens. Materials and Methods 19 patients (pts.) were enrolled on study. 17 pts. were male and 2 were female. 18 pts. had mesothelioma and 1 had non-small cell lung cancer. Mean age was 59 yrs with a range of 47 to 72 years. One patient did not complete treatment due to progressive disease. Patients who completed treatment received from 5760 to 6300 cGy. Dose volume histography and multiple non-coplanar and non-coaxial fields were used. Patients received a continuous infusion of paclitaxel for 120 hours every three weeks during radiation therapy. The Results MTD of paclitaxel was determined to be 105 mg/m 2 delivered as a 120-hour continuous infusion. The dose-limiting toxicity of paclitaxel was neutropenia at 120 mg/m 2 given over 120 hrs. 13 patients were assessable for local control; 4 pts. are too early to evaluate and 2 pts. did not return for follow-up. (11(13)) pts. achieved local control. 3 of 13 patients are free of disease. 10 tumor biopsies were taken from 4 mesothelioma pts. Biopsies were taken prior to the paclitaxel infusion and then during the infusion. A modest G 2 /M block was observed in only 1 of the 5 specimens taken during the paclitaxel infusion. Conclusions This study demonstrates that paclitaxel can be safely delivered as a 120-hour continuous infusion at 105 mg/m 2 with concurrent thoracic radiotherapy. However, the biologic effect of

  3. 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 ...

  4. Ultrastructural morphology and localisation of cisplatin-induced platinum-DNA adducts in a cisplatin-sensitive and -resistant human small cell lung cancer cell line using electron microscopy

    NARCIS (Netherlands)

    Meijer, C; van Luyn, MJA; Nienhuis, EF; Blom, N; Mulder, NH; de Vries, EGE

    2001-01-01

    Ultrastructural morphology (transmission electron microscopy) and localisation of cisplatin-induced platinum (Pt)-DNA adducts (immunoelectron microscopy) were analysed in the human small cell lung cancer cell line GLC(4) and its 40-fold in vitro acquired cisplatin-resistant subline GLC(4)-CDDP,

  5. 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.

  6. The sensitivity of human mesenchymal stem cells to ionizing radiation

    International Nuclear Information System (INIS)

    Chen, M.-F.; Lin, C.-T.; Chen, W.-C.; Yang, C.-T.; Chen, C.-C.; Liao, S.-K.; Liu, J.M.; Lu, C.-H.; Lee, K.-D.

    2006-01-01

    Purpose: Recent studies have shown that mesenchymal stem cells (MSCs) obtained from bone marrow transplantation patients originate from the host. This clinical observation suggests that MSCs in their niches could be resistant to irradiation. However, the biologic responses of bone marrow MSCs to irradiation have rarely been described in the literature. Methods and Materials: In this study, human bone marrow-derived, clonally expanded MSCs were used to investigate their sensitivity to irradiation in vitro, and the cellular mechanisms that may facilitate resistance to irradiation. The human lung cancer cell line A549 and the breast cancer cell line HCC1937 were used as controls for radiosensitivity; the former line has been shown to be radioresistant and the latter radiosensitive. We then examined their in vitro biologic changes and sensitivities to radiation therapy. Results: Our results suggest that MSCs are characterized as resistant to irradiation. Several cellular mechanisms were demonstrated that may facilitate resistance to irradiation: ATM protein phosphorylation, activation of cell-cycle checkpoints, double-strand break repair by homologous recombination and nonhomologous end joining (NHEJ), and the antioxidant capacity for scavenging reactive oxygen species. Conclusions: As demonstrated, MSCs possess a better antioxidant reactive oxygen species-scavenging capacity and active double-strand break repair to facilitate their radioresistance. These findings provide a better understanding of radiation-induced biologic responses in MSCs and may lead to the development of better strategies for stem cell treatment and cancer therapy

  7. Nuclear COMMD1 Is Associated with Cisplatin Sensitivity in Ovarian Cancer

    NARCIS (Netherlands)

    Fedoseienko, Alina; Wieringa, Hylke W.; Wisman, G. Bea A.; Duiker, Evelien; Reyners, Anna K. L.; Hofker, Marten H.; van der Zee, Ate G. J.; Sluis, van de Bart; van Vugt, Marcel A. T. M.

    2016-01-01

    Copper metabolism MURR1 domain 1 (COMMD1) protein is a multifunctional protein, and its expression has been correlated with patients' survival in different types of cancer. In vitro studies revealed that COMMD1 plays a role in sensitizing cancer cell lines to cisplatin, however, the mechanism and

  8. Ovarian and Breast Cancer Spheres Are Similar in Transcriptomic Features and Sensitive to Fenretinide

    Directory of Open Access Journals (Sweden)

    Haiwei Wang

    2013-01-01

    Full Text Available Cancer stem cells (CSCs are resistant to chemotherapy and are ability to regenerate cancer cell populations, thus attracting much attention in cancer research. In this report, we first demonstrated that sphere cells from ovarian cancer cell line A2780 shared many features of CSCs, such as resistance to cisplatin and able to initiate tumors in an efficient manner. Then, we conducted cDNA microarray analysis on spheres from ovarian A2780 cells, and from breast MCF7 and SUM159 cells, and found that molecular pathways underlying spheres from these cancer cell lines were similar to a large extent, suggesting that similar mechanisms are involved in the genesis of CSCs in both ovarian and breast cancer types. In addition, we showed that spheres from these cancer types were highly sensitive to fenretinide, a stimulus of oxidative stress-mediated apoptosis in cancer cells. Thus, our results not only provide important insights into mechanisms underlying CSCs in ovarian and breast cancer, but also lead to the development of more sophisticated protocols of cancer therapy in near future.

  9. 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...

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

    International Nuclear Information System (INIS)

    Flusberg, Deborah A; Sorger, Peter K

    2013-01-01

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

  11. Spectrofluorometric determination of intracellular levels of reactive oxygen species in drug-sensitive and drug-resistant cancer cells using the 2',7'-dichlorofluorescein diacetate assay

    Energy Technology Data Exchange (ETDEWEB)

    Loetchutinat, Chatchanok [Laboratory of Physical Chemistry, Molecular and Cellular Biology, Faculty of Science, Burapha University, Bangsaen, Chonburi 20131 (Thailand); Kothan, Suchart [Laboratory of Physical Chemistry, Molecular and Cellular Biology, Faculty of Science, Burapha University, Bangsaen, Chonburi 20131 (Thailand); Dechsupa, Samarn [Laboratory of Physical Chemistry, Molecular and Cellular Biology, Faculty of Science, Burapha University, Bangsaen, Chonburi 20131 (Thailand); Meesungnoen, Jintana [Laboratory of Physical Chemistry, Molecular and Cellular Biology, Faculty of Science, Burapha University, Bangsaen, Chonburi 20131 (Thailand); Departement de medecine nucleaire et de radiobiologie, Faculte de medecine, Groupe en sciences des radiations, Universite de Sherbrooke, Sherbrooke, Quebec, J1H 5N4 (Canada); Jay-Gerin, Jean-Paul [Departement de medecine nucleaire et de radiobiologie, Faculte de medecine, Groupe en sciences des radiations, Universite de Sherbrooke, Sherbrooke, Quebec, J1H 5N4 (Canada); Mankhetkorn, Samlee [Laboratory of Physical Chemistry, Molecular and Cellular Biology, Faculty of Science, Burapha University, Bangsaen, Chonburi 20131 (Thailand)]. E-mail: samlee@bucc4.buu.ac.th

    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{sub 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{sup 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: k{sub e}) and (ii) oxidation of DCHF by ROS{sub i} (second-order rate constant: k{sub 2}), the parameters intervening in DCF formation, k{sub e} and the product of k{sub 2} by the ROS{sub 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 k{sub 2}[ROS{sub i}] was found to be similar in the four cell lines considered, with a mean value of (5.3+/-0.9)x10{sup -7}cell{sup -1}s{sup -1}. Assuming that H{sub 2}O{sub 2} (in combination with peroxidases) is the primary responsible species for DCHF oxidation in intact cells, and using the rate constant value k2=790+/-62M-1s-1 established in our laboratory for the reaction of DCHF with H{sub 2}O{sub 2} in the presence of horseradish peroxidase, the mean value of the intracellular levels of ROS{sub i} in those cells was estimated to be 0.67+/-0.16n

  12. Hormone Therapy for Breast Cancer

    Science.gov (United States)

    ... Common Cancer Types Recurrent Cancer Common Cancer Types Bladder Cancer Breast Cancer Colorectal Cancer Kidney (Renal Cell) Cancer ... sensitive breast cancer cells contain proteins called hormone receptors that become activated when hormones bind to them. ...

  13. 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. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Caffeine markedly sensitizes human mesothelioma cell lines to pemetrexed

    Science.gov (United States)

    Min, Sang Hee; Goldman, I. David; Zhao, Rongbao

    2013-01-01

    Pemetrexed is a new generation antifolate approved for the treatment of mesothelioma and non-small cell lung cancer. Caffeine is known to augment radiation or chemotherapeutic drug-induced cell killing. The current study addresses the impact of caffeine on the activity of pemetrexed in mesothelioma cell lines. Caffeine enhanced pemetrexed activity in all four mesothelioma cell lines tested (H2052, H2373, H28 and MSTO-211H). Caffeine sensitized H2052 cells in a dose- and schedule-dependent manner, and was associated with a markedly decreased clonogenic survival. Caffeine sensitization occurred only in cells subjected to pulse, but not continuous, exposure to pemetrexed. Similar pemetrexed sensitization was also observed with the clinically better tolerated caffeine analog, theobromine. Pemetrexed sensitization by caffeine was associated with an increase in pemetrexed-induced phosphorylation of ataxia-telangiectasia-mutated (ATM) and Chk1. These data indicate that caffeine and its analog, theobromine, may be a useful approach to enhance pemetrexed-based chemotherapy. PMID:17594092

  15. General Information about Small Cell Lung Cancer

    Science.gov (United States)

    ... Lung Cancer Prevention Lung Cancer Screening Research Small Cell Lung Cancer Treatment (PDQ®)–Patient Version General Information About Small Cell Lung Cancer Go to Health Professional Version Key Points Small ...

  16. Stages of Small Cell Lung Cancer

    Science.gov (United States)

    ... Lung Cancer Prevention Lung Cancer Screening Research Small Cell Lung Cancer Treatment (PDQ®)–Patient Version General Information About Small Cell Lung Cancer Go to Health Professional Version Key Points Small ...

  17. Local advanced transitional cell cancer and squamous cell cancer of ...

    African Journals Online (AJOL)

    Case report: A 51-year-old man presented with a locally advanced squamous cell cancer of the periurethral tissues as well as an underlying isolated transitional cell cancer of the urethra. Chemotherapy with Gemcitabin and Cisplatinum together with local radiation to the pelvis and the perineum was given. There was ...

  18. X-rays sensitive mammalian cell mutant

    International Nuclear Information System (INIS)

    Utsumi, Hiroshi

    1982-01-01

    A phenomenon that in x-ray-sensitive mammalian-cell mutants, cellular death due to x-ray radiation was not increased by caffeine, but on the contrary, the dead cells were resuscitated by it was discussed. The survival rate of mutant cells increased by caffein in a low concentration. This suggested that caffeine may have induced some mechanism to produce x-ray resistant mutant cells. Postirradiation treatment with caffeine increased considerably the survival rate of the mutant cells, and this suggested the existence of latent caffeine-sensitive potentially lethal damage repair system. This system, after a few hours, is thought to be substituted by caffeine-resistant repair system which is induced by caffeine, and this may be further substituted by x-ray-resistant repair system. The repair system was also induced by adenine. (Ueda, J.)

  19. A new prospect in cancer therapy: targeting cancer stem cells to eradicate cancer.

    Science.gov (United States)

    Chen, Li-Sha; Wang, An-Xin; Dong, Bing; Pu, Ke-Feng; Yuan, Li-Hua; Zhu, Yi-Min

    2012-12-01

    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.

  20. Susceptibility of ATM-deficient pancreatic cancer cells to radiation.

    Science.gov (United States)

    Ayars, Michael; Eshleman, James; Goggins, Michael

    2017-05-19

    Ataxia telangiectasia mutated (ATM) is inactivated in a significant minority of pancreatic ductal adenocarcinomas and may be predictor of treatment response. We determined if ATM deficiency renders pancreatic cancer cells more sensitive to fractionated radiation or commonly used chemotherapeutics. ATM expression was knocked down in three pancreatic cancer cell lines using ATM-targeting shRNA. Isogenic cell lines were tested for sensitivity to several chemotherapeutic agents and radiation. DNA repair kinetics were analyzed in irradiated cells using the comet assay. We find that while rendering pancreatic cancer cells ATM-deficient did not significantly change their sensitivity to several chemotherapeutics, it did render them exquisitely sensitized to radiation. Pancreatic cancer ATM status may help predict response to radiotherapy.

  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. Elevated pressure, a novel cancer therapeutic tool for sensitizing cisplatin-mediated apoptosis in A549

    International Nuclear Information System (INIS)

    Oh, Sangnam; Kim, Yanghee; Kim, Joonhee; Kwon, Daeho; Lee, Eunil

    2010-01-01

    Research highlights: → Sensitized apoptosis in cancer cells stimulated by EP precondition with p53 dependence. → EP attenuates several CDDP-resistance mechanisms. → 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.

  3. Epigenetics in cancer stem cells.

    Science.gov (United States)

    Toh, Tan Boon; Lim, Jhin Jieh; Chow, Edward Kai-Hua

    2017-02-01

    Compelling evidence have demonstrated that bulk tumors can arise from a unique subset of cells commonly termed "cancer stem cells" that has been proposed to be a strong driving force of tumorigenesis and a key mechanism of therapeutic resistance. Recent advances in epigenomics have illuminated key mechanisms by which epigenetic regulation contribute to cancer progression. In this review, we present a discussion of how deregulation of various epigenetic pathways can contribute to cancer initiation and tumorigenesis, particularly with respect to maintenance and survival of cancer stem cells. This information, together with several promising clinical and preclinical trials of epigenetic modulating drugs, offer new possibilities for targeting cancer stem cells as well as improving cancer therapy overall.

  4. The study on the effect of artesunate on the radio-sensitivity of human cervical cancer

    International Nuclear Information System (INIS)

    Geng Chong; Cao Jianping; Ni Qianying

    2011-01-01

    To investigate the effect of artesunate on radio-sensitivity of human cervical cancer cells in vitro. The human cervical cancer cells HeLa and Siha were used as the experimental cells. MTT assay was used to determine the most appropriate drug concentration in the subsequent experiment, and the effect of human cervical cancer cells treated with artesunate and irradiation of 60 Co γ-rays was studied by using conventional chromosomal aberration analysis and cytokinesis block method (CB method). The results show that when the concentration of artesunate in this experiment was 2.0 μmol/L for HeLa cell and 4.0 μmol/L for Siha cell respectively, the chromosome aberration, micronuclei cell and micronuclei rates of HeLa cells treated with artesunate were more serious than that of the only irradiation, but there is almost no change with Siha cells. (authors)

  5. Arsenic trioxide inhibits cell proliferation and human papillomavirus oncogene expression in cervical cancer cells

    International Nuclear Information System (INIS)

    Wang, Hongtao; Gao, Peng; Zheng, Jie

    2014-01-01

    Highlights: • As 2 O 3 inhibits growth of cervical cancer cells and expression of HPV oncogenes in these cells. • HPV-negative cervical cancer cells are more sensitive to As 2 O 3 than HPV-positive cervical cancer cells. • HPV-18 positive cervical cancer cells are more sensitive to As 2 O 3 than HPV-16 positive cancer cells. • Down-regulation of HPV oncogenes by As 2 O 3 is partially due to the diminished AP-1 binding. - Abstract: Arsenic trioxide (As 2 O 3 ) has shown therapeutic effects in some leukemias and solid cancers. However, the molecular mechanisms of its anticancer efficacy have not been clearly elucidated, particularly in solid cancers. Our previous data showed that As 2 O 3 induced apoptosis of human papillomavirus (HPV) 16 DNA-immortalized human cervical epithelial cells and cervical cancer cells and inhibited the expression of HPV oncogenes in these cells. In the present study, we systemically examined the effects of As 2 O 3 on five human cervical cancer cell lines and explored the possible molecular mechanisms. MTT assay showed that HPV-negative C33A cells were more sensitive to growth inhibition induced by As 2 O 3 than HPV-positive cervical cancer cells, and HPV 18-positive HeLa and C4-I cells were more sensitive to As 2 O 3 than HPV 16-positive CaSki and SiHa cells. After As 2 O 3 treatment, both mRNA and protein levels of HPV E6 and E7 obviously decreased in all HPV positive cell lines. In contrast, p53 and Rb protein levels increased in all tested cell lines. Transcription factor AP-1 protein expression decreased significantly in HeLa, CaSki and C33A cells with ELISA method. These results suggest that As 2 O 3 is a potential anticancer drug for cervical cancer

  6. Experimental investigations on the relationship between radiation dose and sensitization of hypoxic cells by electron affinic compounds. Coordinated programme on improvement in radiotherapy of cancer using modifiers of radiosensitivity of cells

    International Nuclear Information System (INIS)

    Revesz, L.

    1981-12-01

    The investigations concern experimental studies on the factors which determine the inherent radiation response of mammalian cells, and the mechanism by which treatment with radiation protectors and hypoxic sensitizers modifies the response. Several mammalian cell lines including some derived from humans, were used in the tests of the biological response to radiation. Especially, the establishment of glutathione-deficient cell lines opened new experimental approaches to the question on the role of aminothiols in determining cellular radiation response. As the endpoints for the effect of radiation, single-strand DNA breaks by means of the sucrose gradient centrifugation and the unwinding technique in weak alkali, and colony forming ability of the cells were chosen. Radical reactions were also studied by the pulse-radiolysis technique. The enhancement of cellular radiosensitivity by oxygen and hypoxic cell sensitizers was found to be directly related to the glutathione level in the cells. Some particular aminothiols could substitute for the effect of glutathione in protecting against sensitization by oxygen and oxygen mimic sensitizers. The post irradiation repair of some DNA lesions induced by oxygen or hypoxic cell sensitizers was also associated with the level of glutathione and some specific aminothiols in the cells. The experiments revealed an efficient cellular cooperation in the repair of radiation induced DNA damage. Pulse radiolysis studies showed radical reactions characteristic for glutathione and not shared by other naturally occurring aminothiols. Inherent glutathione appears to play an important role in determining the intrinsic radiosensitivity of cells and the result of treatment with radioprotective and radiosensitizing substances. In particular, glutathione participates in both immediate radical reactions following exposure to ionizing radiation, and in the subsequent biochemical processes, and functions in promoting repair of the radiation damage

  7. Cancer Stem Cells and stress induced evolution - understanding the ...

    Indian Academy of Sciences (India)

    Dr S Bapat

    2015-11-08

    Nov 8, 2015 ... Most therapies fail to consider differential drug sensitivities of various cells in a tumor. (Tumor Cell Heterogeneity). • Drug refractory behaviour of tumor cells may arise due to either –. - Intrinsic drug resistance mechanisms (Molecular Heterogeneity). - Cell dormancy / reversible quiescence (Cancer stem ...

  8. 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. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Photochromic dye-sensitized solar cells

    Directory of Open Access Journals (Sweden)

    Noah M. Johnson

    2015-11-01

    Full Text Available We report the fabrication and characterization of photochromic dye sensitized solar cells that possess the ability to change color depending on external lighting conditions. This device can be used as a “smart” window shade that tints, collects the sun's energy, and blocks sunlight when the sun shines, and is completely transparent at night.

  10. Effect of 17-AAG on radio-sensitivity of HeLa and V79 cells

    International Nuclear Information System (INIS)

    Pan Yanling; Hong Chengjiao; Zhang Baoguo

    2010-01-01

    In order to investigate the radio-sensitizing effect of 17-AAG, an inhibitor of Heat Shock Protein 90, on human Uterine Cervix Cancer HeLa and V79 cells, Clonogenic assay was used to observe the cell survival rate. The results show that 17-AAG can decrease obviously (p 0.05). This indicates that 17-AAG may enhance the radio-sensitivity of the HeLa cell line and has no effect on the V79 cell line. (authors)

  11. Icotinib might be effective for the treatment of leptomeningeal carcinomatosis in non-small cell lung cancer with sensitive EGFR mutations.

    Science.gov (United States)

    Gong, Lei; Xiong, Ming; Huang, Zhiyu; Miao, Lulu; Fan, Yun

    2015-09-01

    The incidence of leptomeningeal carcinomatosis (LMC) has increased in patients with metastatic non-small cell lung cancer (NSCLC). This study aimed to evaluate the effect of icotinib in the treatment of LMC. Twenty-one NSCLC patients diagnosed with LMC and treated with icotinib were retrospectively reviewed. An exon 21 point mutation and an exon 19 deletion of EGFR were found in 10 and 11 patients, respectively. A standard dose of icotinib (125 mg/day, three times a day) was prescribed to 16 patients without previous icotinib therapy. A double dose of icotinib was prescribed to five patients who developed LMC during icotinib therapy with a standard dose. Eighteen of 20 patients showed improvement of dizziness and headache. Seventeen of 21 patients had an improved Eastern Cooperative Oncology Group performance status (ECOG PS) score after icotinib treatment. The median overall survival of the patients after the diagnosis of LMC was 10.1 months (95% confidence interval (CI): 8.4-12.0 months). Univariate analysis showed that the ECOG PS score, parenchymal brain metastasis, and previous icotinib administration were significantly associated with patient survival. Multivariate analysis also demonstrated that the ECOG PS score was an independent predictor for survival. Our results suggest that icotinib is effective for the treatment of LMC from NSCLC with an EGFR mutation, especially for patients with a good ECOG PS score. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  12. Oxygen-dependent sensitization of irradiated cells

    International Nuclear Information System (INIS)

    Ewing, D.; Powers, E.L.

    1979-01-01

    Attention is focused primarily on O 2 effects in three biological systems, all tested in suspension: bacterial spores, vegetative bacterial cells, and mammalian cells. Information from these systems shows that O 2 has more than one process through which it can act. Studies with bacterial spore suspensions provide clear evidence that multiple components to oxygen-dependent radiation sensitization exist. Studies with mammalian cell suspensions also show that at least two oxygen-dependent sensitization processes can be distinguished. Similar studies with vegetative bacteria in suspension have not resolved oxic sensitization into components. The roles of water-derived radicals in radiation sensitivity and, specifically, in sensitization by O 2 were examined. OH radicals are clearly implicated in damage in all three biological test systems. However, the specific roles proposed for OH radicals are different in these organisms. In bacterial spores, OH radical removal in itself does not protect in anoxia or in high concentrations of O 2 . OH radical removal over a limited intermediate range of O 2 concentrations will, however, protect. OH radical scavenging probably results in the formation of the actual protector. In bacteria, the supposition is that OH radical removal will protect both in anoxia and in the presence of O 2 . OH radicals probably react with a cellular target molecule and leave a radicalsite; this is the site which can then react with O 2 to cause damage; DNA is the likely cellular target. In mammalian cells, a reaction scheme, similar to that proposed for bacteria, has been suggested for O 2 -dependent sensitization

  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. Recent Advances in Dye Sensitized Solar Cells

    Directory of Open Access Journals (Sweden)

    Umer Mehmood

    2014-01-01

    Full Text Available Solar energy is an abundant and accessible source of renewable energy available on earth, and many types of photovoltaic (PV devices like organic, inorganic, and hybrid cells have been developed to harness the energy. PV cells directly convert solar radiation into electricity without affecting the environment. Although silicon based solar cells (inorganic cells are widely used because of their high efficiency, they are rigid and manufacturing costs are high. Researchers have focused on organic solar cells to overcome these disadvantages. DSSCs comprise a sensitized semiconductor (photoelectrode and a catalytic electrode (counter electrode with an electrolyte sandwiched between them and their efficiency depends on many factors. The maximum electrical conversion efficiency of DSSCs attained so far is 11.1%, which is still low for commercial applications. This review examines the working principle, factors affecting the efficiency, and key challenges facing DSSCs.

  15. 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.

  16. Semiconductor quantum dot-sensitized solar cells.

    Science.gov (United States)

    Tian, Jianjun; Cao, Guozhong

    2013-10-31

    Semiconductor quantum dots (QDs) have been drawing great attention recently as a material for solar energy conversion due to their versatile optical and electrical properties. The QD-sensitized solar cell (QDSC) is one of the burgeoning semiconductor QD solar cells that shows promising developments for the next generation of solar cells. This article focuses on recent developments in QDSCs, including 1) the effect of quantum confinement on QDSCs, 2) the multiple exciton generation (MEG) of QDs, 3) fabrication methods of QDs, and 4) nanocrystalline photoelectrodes for solar cells. We also make suggestions for future research on QDSCs. Although the efficiency of QDSCs is still low, we think there will be major breakthroughs in developing QDSCs in the future.

  17. General Information about Renal Cell Cancer

    Science.gov (United States)

    ... Tumors Treatment Genetics of Kidney Cancer Research Renal Cell Cancer Treatment (PDQ®)–Patient Version General Information About Renal Cell Cancer Go to Health Professional Version Key Points Renal ...

  18. Treatment Option Overview (Renal Cell Cancer)

    Science.gov (United States)

    ... Tumors Treatment Genetics of Kidney Cancer Research Renal Cell Cancer Treatment (PDQ®)–Patient Version General Information About Renal Cell Cancer Go to Health Professional Version Key Points Renal ...

  19. Drugs Approved for Kidney (Renal Cell) Cancer

    Science.gov (United States)

    ... Your Treatment Research Drugs Approved for Kidney (Renal Cell) Cancer This page lists cancer drugs approved by the ... not listed here. Drugs Approved for Kidney (Renal Cell) Cancer Afinitor (Everolimus) Aldesleukin Avastin (Bevacizumab) Axitinib Bevacizumab Cabometyx ( ...

  20. Nuclear COMMD1 Is Associated with Cisplatin Sensitivity in Ovarian Cancer.

    Directory of Open Access Journals (Sweden)

    Alina Fedoseienko

    Full Text Available Copper metabolism MURR1 domain 1 (COMMD1 protein is a multifunctional protein, and its expression has been correlated with patients' survival in different types of cancer. In vitro studies revealed that COMMD1 plays a role in sensitizing cancer cell lines to cisplatin, however, the mechanism and its role in platinum sensitivity in cancer has yet to be established. We evaluated the role of COMMD1 in cisplatin sensitivity in A2780 ovarian cancer cells and the relation between COMMD1 expression and response to platinum-based therapy in advanced stage high-grade serous ovarian cancer (HGSOC patients. We found that elevation of nuclear COMMD1 expression sensitized A2780 ovarian cancer cells to cisplatin-mediated cytotoxicity. This was accompanied by a more effective G2/M checkpoint, and decreased protein expression of the DNA repair gene BRCA1, and the apoptosis inhibitor BCL2. Furthermore, COMMD1 expression was immunohistochemically analyzed in two tissue micro-arrays (TMAs, representing a historical cohort and a randomized clinical trial-based cohort of advanced stage HGSOC tumor specimens. Expression of COMMD1 was observed in all ovarian cancer samples, however, specifically nuclear expression of COMMD1 was only observed in a subset of ovarian cancers. In our historical cohort, nuclear COMMD1 expression was associated with an improved response to chemotherapy (OR = 0.167; P = 0.038, although this association could not be confirmed in the second cohort, likely due to sample size. Taken together, these results suggest that nuclear expression of COMMD1 sensitize ovarian cancer to cisplatin, possibly by modulating the G2/M checkpoint and through controlling expression of genes involved in DNA repair and apoptosis.

  1. Plasmonic Dye-Sensitized Solar Cells

    KAUST Repository

    Ding, I-Kang

    2010-12-14

    This image presents a scanning electron microscopy image of solid state dye-sensitized solar cell with a plasmonic back reflector, overlaid with simulated field intensity plots when monochromatic light is incident on the device. Plasmonic back reflectors, which consist of 2D arrays of silver nanodomes, can enhance absorption through excitation of plasmonic modes and increased light scattering, as reported by Michael D. McGehee, Yi Cui, and co-workers.

  2. Nanostructured dye-sensitized solar cells

    OpenAIRE

    Palma, Giuseppina

    2014-01-01

    2012/2013 Dye-sensitized solar cells (DSSCs) represent a promising alternative to silicon-based technology. From the first publications about DSSCs in the 90s, they are considered an important breakthrough for achieving high efficiency by using relatively inexpensive and abundant materials. Stability and efficiency are two crucial points in the development of this new class of hybrid photovoltaic devices. Most of the DSSC studies carried out over the past twenty years are based on the o...

  3. 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.

  4. Unique proteomic signature for radiation sensitive patients; a comparative study between normo-sensitive and radiation sensitive breast cancer patients

    International Nuclear Information System (INIS)

    Skiöld, Sara; Azimzadeh, Omid; Merl-Pham, Juliane; Naslund, Ingemar; Wersall, Peter; Lidbrink, Elisabet; Tapio, Soile; Harms-Ringdahl, Mats; Haghdoost, Siamak

    2015-01-01

    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