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Sample records for cancer cell sensitivity

  1. Gene sensitizes cancer cells to chemotherapy drugs

    Science.gov (United States)

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

  2. Sensitizing Cancer Cells: Is It Really All about U?

    OpenAIRE

    Stover, Patrick J.; Weiss, Robert S.

    2012-01-01

    In this issue of Cancer Cell, Hu et al. report that TMPK and RNR, two key enzymes in deoxyribonucleotide biosynthesis, co-localize to damaged DNA and produce nucleotides necessary for DNA repair while suppressing uracil incorporation. TMPK inhibition disrupts this balance and selectively sensitizes cancer cells to low-dose chemotherapy.

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

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    Teruki Yanagi

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

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

    Indian Academy of Sciences (India)

    2017-02-03

    Feb 3, 2017 ... Constitutively activated ERK sensitizes cancer cells to doxorubicin: Involvement of p53-EGFR-ERK pathway. RATNA KUMARI. 1,†. , SURBHI CHOUHAN. 1,†. , SNAHLATA SINGH. 1,†. , RISHI RAJ CHHIPA. 2. ,. AMRENDRA KUMAR AJAY. 3 and MANOJ KUMAR BHAT*. National Centre for Cell Science, ...

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

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    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. DNA methylation and sensitivity to antimetabolites in cancer cell lines.

    Science.gov (United States)

    Sasaki, Shin; Kobunai, Takashi; Kitayama, Joji; Nagawa, Hirokazu

    2008-02-01

    The prediction of the cellular direction of metabolic pathways toward either DNA synthesis or DNA methylation is crucial for determining the susceptibility of cancers to anti-metabolites such as fluorouracil (5-FU). We genotyped the methylenetetrahydrofolate reductase (MTHFR) gene in NCI-60 cancer cell lines, and identified the methylation status of 24 tumor suppressor genes using methylation-specific multiplex ligation-dependent probe amplification. The susceptibility of the cancer cell lines to seven antimetabolites was then determined. Cells homozygous for CC at MTHFR-A1298C were significantly more sensitive to cyclocytidine, cytarabine (AraC) and floxuridine than those with AA or AC (p=0.0215, p=0.0166, and p=0.0323, respectively), and carried more methylated tumor suppressor genes (p=0.0313). Among the 12 tumor suppressor genes which were methylated in >25% of cancer cell lines, the methylation status of TIMP3, APC and IGSF4 significantly correlated with sensitivity to pyrimidine synthesis inhibitors. In particular, cells with methylated TIMP3 had reduced mRNA levels and were significantly more sensitive to aphidicolin-glycinate, AraC and 5-FU than cells with unmethylated TIMP3. We speculate that MTHFR-A1298C homozygous CC might direct the methylation rather than the synthesis of DNA, and result in the methylation of several tumor suppressor genes such as TIMP3. These genes could be useful biological markers for predicting the efficacy of antimetabolites.

  7. NHERF1 Enhances Cisplatin Sensitivity in Human Cervical Cancer Cells.

    Science.gov (United States)

    Tao, Tao; Yang, Xiaomei; Qin, Qiong; Shi, Wen; Wang, Qiqi; Yang, Ying; He, Junqi

    2017-01-12

    Cervical cancer is one of the most common female malignancies, and cisplatin-based chemotherapy is routinely utilized in locally advanced cervical cancer patients. However, resistance has been the major limitation. In this study, we found that Na⁺/H⁺ Exchanger Regulatory Factor 1 (NHERF1) was downregulated in cisplatin-resistant cells. Analysis based on a cervical cancer dataset from The Cancer Genome Atlas (TCGA) showed association of NHERF1 expression with disease-free survival of patients received cisplatin treatment. NHERF1 overexpression inhibited proliferation and enhanced apoptosis in cisplatin-resistant HeLa cells, whereas NHERF1 knockdown had inverse effects. While parental HeLa cells were more resistant to cisplatin after NHERF1 knockdown, NHERF1 overexpression in CaSki cells promoted cisplatin sensitivity. Overexpression and knockdown studies also showed that NHERF1 significantly inhibited AKT and extracellular signal-regulated kinase (ERK) signaling pathways in cisplatin-resistant cells. Taken together, our results provide the first evidence that NHERF1 can sensitize cisplatin-refractory cervical cancer cells. This study may help to increase understanding of the molecular mechanisms underlying cisplatin resistance in tumors.

  8. 53BP1 sensitizes breast cancer cells to 5-fluorouracil.

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    Xiaoyan Li

    Full Text Available Chemoresistance of breast cancer is a worldwide problem for breast cancer and the resistance to chemotherapeutic agents frequently led to the subsequent recurrence and metastasis. In our previous study, we have found that 53BP1 showed a gradual decrease during the progression of breast cancer and loss of 53BP1 was associated with metastasis and poor prognosis in breast cancer. Here we aimed to reveal whether 53BP1 could sensitize breast cancer to 5-Fu. We found that ectopic expression of 53BP1 can significantly sensitize breast cancer cells to 5-Fu while knockdown of 53BP1 conferred the resistance. The in vivo experiments confirmed that overexpression of 53BP1 in combination with 5-Fu markedly inhibited growth of xenotransplanted tumors in nude mice when compared to either agent alone. Furthermore, we demonstrated that 53BP1 regulated the sensitivity to 5-Fu through thymidylate synthase (TS and dihydropyrimidine dehydrogenase (DPYD. The present studies provide a new clue that combination of 5-Fu and 53BP1 could be a potential novel targeted strategy for overcoming breast cancer chemoresistance.

  9. Inhibition of Skp2 sensitizes lung cancer cells to paclitaxel

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    Huang T

    2017-01-01

    Full Text Available Tonghai Huang, Lin Yang, Guangsuo Wang, Guanggui Ding, Bin Peng, Yuxin Wen, Zheng Wang Department of Thoracic Surgery, Shenzhen People’s Hospital, Shenzhen, Guangdong Province, People’s Republic of China Abstract: S-phase kinase-associated protein 2 (Skp2 is an E3 ubiquitin ligase and plays an important role in the control of cell cycle progression. Skp2 is upregulated in several cancers, including lung cancers, but the role of Skp2 in the tumorigenesis and anticancer drug resistance in human lung cancer remains to be determined. We report here that Skp2 positively regulated mitotic arrest deficient 2 (MAD2 expression and that inhibition of Skp2 sensitizes human lung cancer cells to paclitaxel. Knockdown of Skp2 by small interfering RNA (siRNA decreased Mad2 messenger RNA (mRNA and protein levels in A549 and NCI-H1975 cells, accompanied with upregulation of p27 but decrease of the phosphorylation of retinoblastoma (Rb. In contrast, ectopic overexpression of Skp2 increased Mad2 mRNA and protein levels and phosphorylation of Rb, while it decreased p27. Pharmacological inhibition of CDK1/2 by flavopiridol or E2F1 with HLM006474 led to downregulation of Mad2 expression and prevented the increase of Mad2 expression by Skp2. Most importantly, pharmacological inhibition of Skp2 sensitized A549 and NCI-H1299 cells to paclitaxel. Our results demonstrated that SKP2 positively regulates the gene expression of MAD2 through p27-CDKs-E2F1 signaling pathway and that inhibition of Skp2 sensitizes A549 and NCI-H1299 cells to paclitaxel, suggesting that small molecule inhibitors of Skp2 are potential agents for the treatment of lung cancer with upregulation of Skp2. Keywords: SKP2, MAD2, spindle assembly checkpoint, lung cancer, paclitaxel

  10. 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

    with parental MCF-7 cells. Our data show that Bcl-2 can protect antiestrogen-resistant breast cancer cells from cisplatin-induced cell death, indicating that the reduced expression of Bcl-2 in the antiestrogen-resistant cells plays a role in sensitizing the cells to cisplatin treatment....... for future breast cancer treatment. In this study, we have investigated the effect of the chemotherapeutic compound cisplatin using a panel of antiestrogen-resistant breast cancer cell lines established from the human breast cancer cell line MCF-7. We show that the antiestrogen-resistant cells...

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

    Science.gov (United States)

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

    2016-09-01

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

  12. Epimorphin-induced MET sensitizes ovarian cancer cells to platinum.

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    Kok-Hooi Yew

    Full Text Available Distinctive genotypic and phenotypic features of ovarian cancer via epithelial-mesenchymal transition (EMT have been correlated with drug resistance and disease recurrence. We investigated whether therapeutic reversal of EMT could re-sensitize ovarian cancer cells (OCCs to existing chemotherapy. We report that epimorphin, a morphogenic protein, has pivotal control over mesenchymal versus epithelial cell lineage decision of the putative OCCs. Exposure to epimorphin induced morphological changes reminiscent of mesenchymal-to-epithelial transition (MET, but in a dose dependent manner, i.e., at 10 µg/mL of epimorphin cells obtain a more mesenchymal-like morphology while at 20 µg/mL of epimorphin cells display an epithelial morphology. The latter changes were accompanied by suppression of mesenchymal markers, such as vimentin (∼8-fold↓, p<0.02, Twist1 (∼7-fold↓, p<0.03, dystroglycan (∼4-fold↓, p<0.01 and palladin (∼3-fold↓, p<0.01. Conversely, significant elevations of KLF4 (∼28-fold↑, p<0.002, β-catenin (∼6-fold↑, p<0.004, EpCAM (∼6-fold↑, p<0.0002 and occludin (∼15-fold↑, p<0.004 mRNAs as part of the commitment to the epithelial cell lineage were detected in response to 20 µg/mL of exogenous epimorphin. Changes in occludin mRNA levels were accompanied by a parallel, albeit weaker expression at the protein level (∼5-fold↑, p<0.001. Likewise, acquisition of epithelial-like properties, including mucin1, CK19, and β-catenin gene expression, was also obtained following epimorphin treatment. Further, MMP3 production was found to be reduced whereas laminin secretion was strongly amplified upon epimorphin-induced MET. These results suggest there is a dosage window for actions of epimorphin on cellular differentiation, wherein it can either suppress or enhance epithelial differentiation of OCCs. Importantly, induction of epithelial-like phenotypes by epimorphin led to an enhanced sensitivity to carboplatin. Overall

  13. Targeting gallbladder cancer: hyaluronan sensitizes cancer cells to chemo-therapeutics.

    Science.gov (United States)

    Ma, Mingzhe; Weng, Mingzhe; Zhang, Mingdi; Qin, Yiyu; Gong, Wei; Quan, Zhiwei

    2015-01-01

    Gallbladder cancer is the most common biliary tract malignancy and the fifth most common gastrointestinal malignancy. Chemo-resistance is the most remarkable characteristic of gallbladder cancer. The relatively dense extracellular space in tumor is the main barrier to nanotherapeutics' anticancer efficacy. Hyaluronan (HA) was shown in our previous study to significantly improve the myxoma virus distribution via promoting the MMP-9 production, which degrades collagen IV. We demonstrated that HA increased the chemo-sensitivity of gallbladder cancer cells both in vitro and in vivo. The in vivo chemo-sensitization effect of HA could partially be due to the penetration-promoting effect of HA via degrading collagen IV.

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

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    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.

  15. Sensitivity of bladder cancer cells to curcumin and its derivatives depends on the extracellular matrix.

    Science.gov (United States)

    Hauser, Paul J; Han, Zhiyong; Sindhwani, Puneet; Hurst, Robert E

    2007-01-01

    Because the response of cancer cells to chemotherapeutic agents depends upon the supporting extracellular matrix (ECM), the response in vivo may not be reproduced in 2-dimensional cell culture. The dose-response to curcumin and two derivatives by bladder cancer cells grown on both normal (SISgel) and cancer-derived ECM (Matrigel) and on plastic were contrasted. Cells grown on Matrigel were resistant to curcumins, but cells growing on SISgel, which mimic cancer cells suppressed by normal ECM, were nearly as sensitive as cells grown on plastic. SV40-immortalized urothelial cells, which are models for premalignant cells, were the most sensitive, but even aggressive cell lines were nearly as sensitive when grown on SISgel as on plastic. Curcumin response depends highly on the supporting ECM, and cells grown on plastic poorly models cells growing on natural ECM. Curcumin could prove an effective chemopreventive for bladder cancer recurrence when administered intravesically post-therapy.

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

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

    2016-01-11

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

  17. Microbeam PIXE analysis of platinum resistant and sensitive ovarian cancer cells

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    Jeynes, J.C.G., E-mail: J.C.Jeynes@surrey.ac.u [Ion Beam Centre, University of Surrey, Guildford GU2 7XH (United Kingdom); Bailey, M.J. [Ion Beam Centre, University of Surrey, Guildford GU2 7XH (United Kingdom); Coley, H. [Faculty of Health and Medical Sciences, University of Surrey, Guildford GU2 7XH (United Kingdom); Kirkby, K.J.; Jeynes, C. [Ion Beam Centre, University of Surrey, Guildford GU2 7XH (United Kingdom)

    2010-06-15

    Microbeam PIXE was used to analyse platinum in single ovarian cancer cells. Carboplatin sensitive and resistant cells were grown as a monolayer on polypropylene and treated with either carboplatin or cisplatin. Pt from the carboplatin could not be detected. The Pt from cisplatin in the cells could be detected, and significantly more Zn was found in the resistant cells compared to the sensitive cells. The sensitive cells probably accumulated more cisplatin than the resistant ones.

  18. 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.

  19. Sensitivity of cancer cells to truncated diphtheria toxin.

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    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.

  20. 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.

  1. Cancer cell sensitivity to bortezomib is associated with survivin expression and p53 status but not cancer cell types

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    Chanan-Khan Asher A

    2010-01-01

    Full Text Available Abstract Background Survivin is known playing a role in drug resistance. However, its role in bortezomib-mediated inhibition of growth and induction of apoptosis is unclear. There are conflicting reports for the effect of bortezomib on survivin expression, which lacks of a plausible explanation. Methods: In this study, we tested cancer cells with both p53 wild type and mutant/null background for the relationship of bortezomib resistance with survivin expression and p53 status using MTT assay, flow cytometry, DNA fragmentation, caspase activation, western blots and RNAi technology. Results We found that cancer cells with wild type p53 show a low level expression of survivin and are sensitive to treatment with bortezomib, while cancer cells with a mutant or null p53 show a high level expression of survivin and are resistant to bortezomib-mediated apoptosis induction. However, silencing of survivin expression utilizing survivin mRNA-specific siRNA/shRNA in p53 mutant or null cells sensitized cancer cells to bortezomib mediated apoptosis induction, suggesting a role for survivin in bortezomib resistance. We further noted that modulation of survivin expression by bortezomib is dependent on p53 status but independent of cancer cell types. In cancer cells with mutated p53 or p53 null, bortezomib appears to induce survivin expression, while in cancer cells with wild type p53, bortezomib downregulates or shows no significant effect on survivin expression, which is dependent on the drug concentration, cell line and exposure time. Conclusions Our findings, for the first time, unify the current inconsistent findings for bortezomib treatment and survivin expression, and linked the effect of bortezomib on survivin expression, apoptosis induction and bortezomib resistance in the relationship with p53 status, which is independent of cancer cell types. Further mechanistic studies along with this line may impact the optimal clinical application of bortezomib in

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

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    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

  3. Probenecid Sensitizes Neuroblastoma Cancer Stem Cells to Cisplatin.

    Science.gov (United States)

    Campos-Arroyo, Denise; Maldonado, Vilma; Bahena, Ivan; Quintanar, Valeria; Patiño, Nelly; Carlos Martinez-Lazcano, Juan; Melendez-Zajgla, Jorge

    2016-01-01

    We used both in vitro cultures of neuroblastoma cell lines and nude-mice xenotransplants to explore the effects of co-administration of cisplatin and probenecid. Probenecid sensitized neuroblastoma cells, including tumor cells with stem features, to the effects of cisplatin, both in vitro and in vivo. This effect was mediated by an increase in the apoptotic cell death and a concomitant decrease in cell proliferation. This effect is accompanied by modulation of the mRNA and protein of the drug efflux transporters MDR1, MRP2, and BCRP. The co-administration of probenecid with cisplatin should be explored as a possible therapeutic strategy.

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

    OpenAIRE

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

    2016-01-01

    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/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...

  5. Flavonoid-induced autophagy in hormone sensitive breast cancer cells.

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    Brunelli, Elisa; Pinton, Giulia; Bellini, Paolo; Minassi, Alberto; Appendino, Giovanni; Moro, Laura

    2009-09-01

    The activity of 8-prenylapigenin (8-PA) and its 3'-methoxylated analogue isocannflavin B (IsoB) was investigated in estrogen-dependent T47-D and estrogen-independent MDA-MB-231 human breast cancer cell lines. 8-PA showed a biphasic effect on T47-D cell proliferation, while no significant effect was observed on MDA-MB-231 cells. Conversely, IsoB exhibited only an inhibitory effect on T47-D cell proliferation, accompanied by the appearance of an intense intracytoplasmic vacuolization of autophagic origin. Moreover, biochemical analysis showed that IsoB reduced Akt phosphorylation and p21(Cip1) expression in T47-D cells. These data show that the prenylflavone moiety is a versatile platform for the induction and modulation of bioactivity.

  6. Modulating autophagy in cancer therapy: advancements and challenges for cancer cell death sensitization.

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    Bhat, Punya; Kriel, Jurgen; Shubha Priya, Babu; Salundi, Basappa; Shivananju, Nanjunda Swamy; Loos, Ben

    2017-12-01

    Autophagy is a major protein degradation pathway capable of upholding cellular metabolism under nutrient limiting conditions, making it a valuable resource to highly proliferating tumour cells. Although the regulatory machinery of the autophagic pathway has been well characterized, accurate modulation of this pathway remains complex in the context of clinical translatability for improved cancer therapies. In particular, the dynamic relationship between the rate of protein degradation through autophagy, i.e. autophagic flux, and the susceptibility of tumours to undergo apoptosis remains largely unclear. Adding to inefficient clinical translation is the lack of measurement techniques that accurately depict autophagic flux. Paradoxically, both increased autophagic flux as well as autophagy inhibition have been shown to sensitize cancer cells to undergo cell death, indicating the highly context dependent nature of this pathway. In this article, we aim to disentangle the role of autophagy modulation in tumour suppression by assessing existing literature in the context of autophagic flux and cellular metabolism at the interface of mitochondrial function. We highlight the urgency to not only assess autophagic flux more accurately, but also to center autophagy manipulation within the unique and inherent metabolic properties of cancer cells. Lastly, we discuss the challenges faced when targeting autophagy in the clinical setting. In doing so, it is hoped that a better understanding of autophagy in cancer therapy is revealed in order to overcome tumour chemoresistance through more controlled autophagy modulation in the future. Copyright © 2017. Published by Elsevier Inc.

  7. Mathematical models of cell phenotype regulation and reprogramming: Make cancer cells sensitive again!

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    Wooten, David J; Quaranta, Vito

    2017-04-01

    A cell's phenotype is the observable actualization of complex interactions between its genome, epigenome, and local environment. While traditional views in cancer have held that cellular and tumor phenotypes are largely functions of genomic instability, increasing attention has recently been given to epigenetic and microenvironmental influences. Such non-genetic factors allow cancer cells to experience intrinsic diversity and plasticity, and at the tumor level can result in phenotypic heterogeneity and treatment evasion. In 2006, Takahashi and Yamanaka exploited the epigenome's plasticity by "reprogramming" differentiated cells into a pluripotent state by inducing expression of a cocktail of four transcription factors. Recent advances in cancer biology have shown not only that cellular reprogramming is possible for malignant cells, but it may provide a foundation for future therapies. Nevertheless, cell reprogramming experiments are frequently plagued by low efficiency, activation of aberrant transcriptional programs, instability, and often rely on expertise gathered from systems which may not translate directly to cancer. Here, we review a theoretical framework tracing back to Waddington's epigenetic landscape which may be used to derive quantitative and qualitative understanding of cellular reprogramming. Implications for tumor heterogeneity, evolution and adaptation are discussed in the context of designing new treatments to re-sensitize recalcitrant tumors. This article is part of a Special Issue entitled: Evolutionary principles - heterogeneity in cancer?, edited by Dr. Robert A. Gatenby. Copyright © 2017. Published by Elsevier B.V.

  8. Aplysin Sensitizes Cancer Cells to TRAIL by Suppressing P38 MAPK/Survivin Pathway

    Directory of Open Access Journals (Sweden)

    Jia Liu

    2014-09-01

    Full Text Available TNF-related apoptosis-inducing ligand (TRAIL is a tumor-selective apoptosis inducer and has been shown to be promising for treating various types of cancers. However, the application of TRAIL is greatly impeded by the resistance of cancer cells to its action. Studies show that overexpression of some critical pro-survival proteins, such as survivin, is responsible for TRAIL resistance. In this study, we found that Aplysin, a brominated compound from marine organisms, was able to restore the sensitivity of cancer cells to TRAIL both in vitro and in vivo. Aplysin was found to enhance the tumor-suppressing capacity of TRAIL on several TRAIL-resistant cancer cell lines. TRAIL-induced apoptosis was also potentiated in A549 and MCF7 cells treated with Aplysin. Survivin downregulation was identified as a mechanism by which Aplysin-mediated TRAIL sensitization of cancer cells. Furthermore, the activation of p38 MAPK was revealed in Aplysin-treated cancer cells, and its inhibitor SB203580 was able to abrogate the promoting effect of Aplysin on the response of cancer cells to TRAIL action, as evidenced by restored survivin expression, elevated cell survival and reduced apoptotic rates. In conclusion, we provided evidence that Aplysin acts as a sensitizer for TRAIL and its effect on p38 MAPK/survivin pathway may partially account for this activity. Considering its low cytotoxicity to normal cells, Aplysin may be a promising agent for cancer treatment in combination with TRAIL.

  9. [Bortezomib enhances the sensitivity of prostate cancer cells to natural killer cell-mediated cytotoxicity].

    Science.gov (United States)

    Hu, Wei; Gao, Zhen-Yu; Wang, Wei

    2014-03-01

    To investigate whether bortezomib can enhance the sensitivity of human prostate cancer (PCa) cells to natural killer (NK) cell-mediated cytotoxicity, and whether it produces the same effect on different PCa cell lines. We treated androgen-dependent PCa LNCaP cells and androgen-independent PCa DU145 cells with bortezomib at the concentrations of 0, 5, 10, 15, 20 and 25 nmol/L for 24, 48 and 72 hours, and then detected the proliferation and apoptosis of the tumor cells by CCK-8 and Annexin V/PI, respectively. The proliferation rates of the DU145 cells treated with 15, 20 and 25 nmol/L bortezomib were (82.79 +/-2.04)%, (73.59+/- 2.95)% and (74.16+/- 6. 16)% at 48 hours and (71.24+/- 5.30)%, (51.20+/- 2.91)% and (38.02+/- 2.67)% at 72 hours, and those of the LNCaP cells were (77.04+/- 7.74)% , (42.61 +/- 6.62)% and (23.85 +/-6.04)% at 48 hours and (36.45 +/-7.02)%, (14.94 +/-5.76)% and (11.65 +/-5. 87)% at 72 hours, both significantly inhibited as compared with the control group (P cancer therapies, and it is more efficacious for androgen-independent prostate cancer.

  10. 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.

  11. 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.

  12. 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.

  13. 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

    2017-09-25

    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.

  14. 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.

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

    Directory of Open Access Journals (Sweden)

    Laird Peter W

    2008-07-01

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

  16. 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.

  17. 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

    (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......Impaired DNA damage response pathways may create vulnerabilities of cancer cells that can be exploited therapeutically. One such selective vulnerability is the sensitivity of BRCA1- or BRCA2-defective tumors (hence defective in DNA repair by homologous recombination, HR) to inhibitors of the poly...... to PARP-1i. Here we addressed these issues using PARP-1i on 20 human cell lines from carcinomas of the breast, prostate, colon, pancreas and ovary. Aberrations of the Mre11-Rad50-Nbs1 (MRN) complex sensitized cancer cells to PARP-1i, while p53 status was less predictive, even in response to PARP-1i...

  18. Pluripotent Stem Cell Protein Sox2 Confers Sensitivity to LSD1 Inhibition in Cancer Cells

    Directory of Open Access Journals (Sweden)

    Xiaoming Zhang

    2013-10-01

    Full Text Available Gene amplification of Sox2 at 3q26.33 is a common event in squamous cell carcinomas (SCCs of the lung and esophagus, as well as several other cancers. Here, we show that the expression of LSD1/KDM1 histone demethylase is significantly elevated in Sox2-expressing lung SCCs. LSD1-specific inhibitors selectively impair the growth of Sox2-expressing lung SCCs, but not that of Sox2-negative cells. Sox2 expression is associated with sensitivity to LSD1 inhibition in lung, breast, ovarian, and other carcinoma cells. Inactivation of LSD1 reduces Sox2 expression, promotes G1 cell-cycle arrest, and induces genes for differentiation by selectively modulating the methylation states of histone H3 at lysines 4 (H3K4 and 9 (H3K9. Reduction of Sox2 further suppresses Sox2-dependent lineage-survival oncogenic potential, elevates trimethylation of histone H3 at lysine 27 (H3K27 and enhances growth arrest and cellular differentiation. Our studies suggest that LSD1 serves as a selective epigenetic target for therapy in Sox2-expressing cancers.

  19. Fasting Cycles Retard Growth of Tumors and Sensitize a Range of Cancer Cell Types to Chemotherapy

    Science.gov (United States)

    Lee, Changhan; Raffaghello, Lizzia; Brandhorst, Sebastian; Safdie, Fernando M.; Bianchi, Giovanna; Martin-Montalvo, Alejandro; Pistoia, Vito; Wei, Min; Hwang, Saewon; Merlino, Annalisa; Emionite, Laura; de Cabo, Rafael; Longo, Valter D.

    2013-01-01

    Short-term starvation (or fasting) protects normal cells, mice, and potentially humans from the harmful side effects of a variety of chemotherapy drugs. Here, we show that treatment with starvation conditions sensitized yeast cells (Saccharomyces cerevisiae) expressing the oncogene-like RAS2val19 to oxidative stress and 15 of 17 mammalian cancer cell lines to chemotherapeutic agents. Cycles of starvation were as effective as chemotherapeutic agents in delaying progression of different tumors and increased the effectiveness of these drugs against melanoma, glioma, and breast cancer cells. In mouse models of neuroblastoma, fasting cycles plus chemotherapy drugs—but not either treatment alone—resulted in long-term cancer-free survival. In 4T1 breast cancer cells, short-term starvation resulted in increased phosphorylation of the stress-sensitizing Akt and S6 kinases, increased oxidative stress, caspase-3 cleavage, DNA damage, and apoptosis. These studies suggest that multiple cycles of fasting promote differential stress sensitization in a wide range of tumors and could potentially replace or augment the efficacy of certain chemotherapy drugs in the treatment of various cancers. PMID:22323820

  20. Fasting cycles retard growth of tumors and sensitize a range of cancer cell types to chemotherapy.

    Science.gov (United States)

    Lee, Changhan; Raffaghello, Lizzia; Brandhorst, Sebastian; Safdie, Fernando M; Bianchi, Giovanna; Martin-Montalvo, Alejandro; Pistoia, Vito; Wei, Min; Hwang, Saewon; Merlino, Annalisa; Emionite, Laura; de Cabo, Rafael; Longo, Valter D

    2012-03-07

    Short-term starvation (or fasting) protects normal cells, mice, and potentially humans from the harmful side effects of a variety of chemotherapy drugs. Here, we show that treatment with starvation conditions sensitized yeast cells (Saccharomyces cerevisiae) expressing the oncogene-like RAS2(val19) to oxidative stress and 15 of 17 mammalian cancer cell lines to chemotherapeutic agents. Cycles of starvation were as effective as chemotherapeutic agents in delaying progression of different tumors and increased the effectiveness of these drugs against melanoma, glioma, and breast cancer cells. In mouse models of neuroblastoma, fasting cycles plus chemotherapy drugs--but not either treatment alone--resulted in long-term cancer-free survival. In 4T1 breast cancer cells, short-term starvation resulted in increased phosphorylation of the stress-sensitizing Akt and S6 kinases, increased oxidative stress, caspase-3 cleavage, DNA damage, and apoptosis. These studies suggest that multiple cycles of fasting promote differential stress sensitization in a wide range of tumors and could potentially replace or augment the efficacy of certain chemotherapy drugs in the treatment of various cancers.

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

    African Journals Online (AJOL)

    Purpose: To demonstrate the effectiveness of Centella asiatica aqueous extract in augmenting the cytotoxic effect of bleomycin in the adenocarcinoma human alveolar basal epithelial A549 cell line. Methods: The inhibitory effect of bleomycin on A549 cells was determined by incubating the cells for 24 h in different ...

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

    Indian Academy of Sciences (India)

    The tumour suppressor gene p53 is mutated in approximately 50% of the human cancers. p53 is involved in genotoxicstress-induced cellular responses. The role of EGFR and ERK in DNA-damage-induced apoptosis is well known. Weinvestigated the involvement of activation of ERK signalling as a consequence of ...

  3. Methoxyphenyl chalcone sensitizes aggressive epithelial cancer to cisplatin through apoptosis induction and cancer stem cell eradication.

    Science.gov (United States)

    Su, Yu-Kai; Huang, Wen-Chien; Lee, Wei-Hwa; Bamodu, Oluwaseun Adebayo; Zucha, Muhammad Ary; Astuti, Indwiani; Suwito, Heri; Yeh, Chi-Tai; Lin, Chien-Min

    2017-05-01

    Current standard chemotherapy for late stage ovarian cancer is found unsuccessful due to relapse after completing the regimens. After completing platinum-based chemotherapy, 70% of patients develop relapse and resistance. Recent evidence proves ovarian cancer stem cells as the source of resistance. Therefore, treatment strategy to target both cancer stem cells and normal stem cells is essential. In this study, we developed a novel chalcone derivative as novel drug candidate for ovarian cancer treatment. We found that methoxyphenyl chalcone was effective to eliminate ovarian cancer cells when given either as monotherapy or in combination with cisplatin. We found that cell viability of ovarian cancer cells was decreased through apoptosis induction. Dephosphorylation of Bcl2-associated agonist of cell death protein was increased after methoxyphenyl chalcone treatment that led to activation of caspases. Interestingly, this drug also worked as a G2/M checkpoint modulator with alternative ways of DNA damage signal-evoking potential that might work to increase response after cisplatin treatment. In addition, methoxyphenyl chalcone was able to suppress autophagic flux and stemness regulator in ovarian spheroids that decreased their survival. Therefore, combination of methoxyphenyl chalcone and cisplatin showed synergistic effects. Taken together, we believe that our novel compound is a promising novel therapeutic agent for effective clinical treatment of ovarian cancer.

  4. Comparisons of Robustness and Sensitivity between Cancer and Normal Cells by Microarray Data

    Directory of Open Access Journals (Sweden)

    Bor-Sen Chen

    2008-01-01

    Full Text Available Robustness is defined as the ability to uphold performance in face of perturbations and uncertainties, and sensitivity is a measure of the system deviations generated by perturbations to the system. While cancer appears as a robust but fragile system, few computational and quantitative evidences demonstrate robustness tradeoffs in cancer. Microarrays have been widely applied to decipher gene expression signatures in human cancer research, and quantification of global gene expression profiles facilitates precise prediction and modeling of cancer in systems biology. We provide several efficient computational methods based on system and control theory to compare robustness and sensitivity between cancer and normal cells by microarray data. Measurement of robustness and sensitivity by linear stochastic model is introduced in this study, which shows oscillations in feedback loops of p53 and demonstrates robustness tradeoffs that cancer is a robust system with some extreme fragilities. In addition, we measure sensitivity of gene expression to perturbations in other gene expression and kinetic parameters, discuss nonlinear effects in feedback loops of p53 and extend our method to robustness-based cancer drug design.

  5. 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.

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

    Directory of Open Access Journals (Sweden)

    Liu Xichun

    2010-08-01

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

  7. Trailing TRAIL Resistance: Novel Targets for TRAIL sensitization in Cancer cells

    Directory of Open Access Journals (Sweden)

    RACHANA eTRIVEDI

    2015-04-01

    Full Text Available Resistance to chemotherapeutic drugs is the major hindrance in the successful cancer therapy. The tumor necrosis factor- related apoptosis- inducing ligand (TRAIL is a member of the Tumor Necrosis Factor (TNF family of ligands which initiates apoptosis in cancer cells through interaction with the death receptors DR4 and DR5. TRAIL is perceived as an attractive chemotherapeutic agent as it specifically targets cancer cells while sparing the normal cells. However TRAIL therapy has a major limitation as a large number of the cancer develop resistance towards TRAIL and escape from the destruction by the immune system. Therefore, elucidation of the molecular targets and signaling pathways responsible for TRAIL resistance is imperative for devising effective therapeutic strategies for TRAIL resistant cancers. Although, various molecular targets leading to TRAIL resistance are well studied, recent studies have implicated that the contribution of some key cellular processes towards TRAIL resistance need to be fully elucidated. These processes primarily include aberrant protein synthesis, protein misfolding, ubiquitin regulated death receptor expression, metabolic pathways, epigenetic deregulation and metastasis. Novel synthetic/natural compounds that could inhibit these defective cellular processes may restore the TRAIL sensitivity and combination therapies with such compounds may resensitize TRAIL resistant cancer cells towards TRAIL-induced apoptosis. In this review, we have summarized the key cellular processes associated with TRAIL resistance and their status as therapeutic targets for novel TRAIL-sensitizing agents.

  8. miR-200/ZEB axis regulates sensitivity to nintedanib in non-small cell lung cancer cells

    OpenAIRE

    Nishijima, Nobuhiko; SEIKE, MASAHIRO; Soeno, Chie; CHIBA, MIKA; Miyanaga, Akihiko; Noro, Rintaro; SUGANO, TEPPEI; Matsumoto , Masaru; Kubota, Kaoru; Gemma, Akihiko

    2016-01-01

    Nintedanib (BIBF1120) is a multi-targeted angiokinase inhibitor and has been evaluated in idiopathic pulmonary fibrosis and advanced non-small cell lung cancer (NSCLC) patients in clinical studies. In the present study, we evaluated the antitumor effects of nintedanib in 16 NSCLC cell lines and tried to identify microRNA (miRNA) associated with sensitivity to nintedanib. No correlations between FGFR, PDGFR and VEGFR family activation and sensitivity to nintedanib were found. The difference in...

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

    National Research Council Canada - National Science Library

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

    2009-01-01

    ... often requires the administration of nanoparticles into a cell culture system or into living organisms . It should be noted, however, that under such conditions nanopaticles are known to adsorb proteins from the biological system, and the resulting heterogeneity in surface proteins may in turn affect the biological effects of nanomaterials . ...

  10. 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

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

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    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. Magnetic nanoparticles sensitize MCF-7 breast cancer cells to doxorubicin-induced apoptosis.

    Science.gov (United States)

    Aljarrah, Khaled; Mhaidat, Nizar M; Al-Akhras, M-Ali H; Aldaher, Ahmad N; Albiss, Ba; Aledealat, Khaled; Alsheyab, Fawzi M

    2012-04-25

    Resistance of breast cancer cells to the available chemotherapeutics is a major obstacle to successful treatment. Recent studies have shown that magnetic nanoparticles might have significant application in different medical fields including cancer treatment. The goal of this study is to verify the ability of magnetic nanoparticles to sensitize cancer cells to the clinically available chemotherapy. The role of iron oxide nanoparticles, static magnetic field, or a combination in the enhancement of the apoptotic potential of doxorubicin against the resistant breast cancer cells, MCF-7 was evaluated using the MTT assay and the propidium iodide method. In the present study, results revealed that pre-incubation of MCF-7 cells with iron oxide nanoparticles before the addition of doxorubicin did not enhance doxorubicin-induced growth inhibition. Pre-incubation of MCF-7 cells with iron oxide nanoparticles followed by a static magnetic field exposure significantly (P magnetic field was dose-dependent where the highest cytotoxicity was seen at 1 tesla. Further experiments revealed that the anti-proliferative effect of this treatment procedure is due to induction of apoptotic cell death. These results might point to the importance of combining magnetic nanoparticles with a static magnetic field in treatment of doxorubicin-refractory breast cancer cells.

  13. Overexpression of granulocyte macrophage colony stimulating factor in breast cancer cells leads towards drug sensitization.

    Science.gov (United States)

    Chaubey, Nidhi; Ghosh, Siddhartha Sankar

    2015-02-01

    This report describes the effect of overexpressing granulocyte macrophage colony stimulating factor (GMCSF) in breast cancer cells, which otherwise is involved in proliferation and differentiation of granulocyte and macrophage lineages. The purified recombinant GMCSF cytokine is known to exert dose-dependent proliferative response on various cancer cells, but its effect during overexpression is yet to be evaluated. In our present study, we have generated MCF-7 (breast cancer) cells overexpressing GMCSF. Interestingly, cell viability studies showed pronounced sensitivity of GMCSF overexpressing MCF-7 cells towards anticancer drugs, such as, doxorubicin, 5FU and cisplatin. These findings were substantiated by cell cycle analysis of the drug-treated GMCSF overexpressing MCF-7 cells. Semiquantitative reverse transcriptase-polymerase chain reaction (RT-PCR) results revealed differential expressions of cyclins, and the carboxyfluorescein succinimidyl ester (CFSE)-based assay established decrease in doubling time of GMCSF overexpressed cells with respect to the control populations. Thus, overexpressing of proliferative GMCSF cytokine in breast cancer cells may increase susceptibility to anticancer drugs.

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

    Science.gov (United States)

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

    2015-01-01

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

  15. Inhibition of telomerase potentiates enzalutamide efficiency of androgen-sensitive human prostate cancer cells.

    Science.gov (United States)

    Gecgel, Karaca Kaan; Muduroglu, Mustafa; Erdogan, Suat

    2017-01-01

    Androgen deprivation therapy (ADT) is one of the main strategies to treat prostate cancer (PCa) at various stages of its development. Androgen receptor (AR) antagonists such as enzalutamide are mainstay treatments for castration-sensitive prostate cancer. Though, a majority of patients initially respond to ADT, most will eventually progress to castrate-resistant, due to the development of different mutations on the AR. PCa cells express high telomerase activity, and there is a correlation between the total activity of telomerase and the Gleason score. Therefore, we hypothesized that the combination of enzalutamide plus a telomerase inhibitor could be more effective than enzalutamide alone in decreasing cell survival. In this study MTT test, RT-qPCR and imagebased cytometry were used to investigate cell viability, apoptosis and cell cycle progression of androgen-responsive human prostate cancer LNCaP cells. The cells were treated with 5 μM enzalutamide and 40 μM telomerase inhibitor BIBR 1532, or with their combinations for 72 hrs. Enzalutamide and BIBR 1532 alone inhibited cell proliferation in a dose-dependent manner. The combinations of the two agents could synergistically induce apoptotic and necrotic cell death. Either inhibition of telomerase by BIBR 1532 or AR blockages by enzalutamide decreased prostate-specific antigen (PSA) and the catalytic component of telomerase, hTERT, expression. These results suggest that telomerase inhibition therapy may contribute to the efficacy of enzalutamide in the androgen-sensitive PCa model.

  16. Magnetic nanoparticles sensitize MCF-7 breast cancer cells to doxorubicin-induced apoptosis

    Directory of Open Access Journals (Sweden)

    Aljarrah Khaled

    2012-04-01

    Full Text Available Abstract Background Resistance of breast cancer cells to the available chemotherapeutics is a major obstacle to successful treatment. Recent studies have shown that magnetic nanoparticles might have significant application in different medical fields including cancer treatment. The goal of this study is to verify the ability of magnetic nanoparticles to sensitize cancer cells to the clinically available chemotherapy. Methods The role of iron oxide nanoparticles, static magnetic field, or a combination in the enhancement of the apoptotic potential of doxorubicin against the resistant breast cancer cells, MCF-7 was evaluated using the MTT assay and the propidium iodide method. Results In the present study, results revealed that pre-incubation of MCF-7 cells with iron oxide nanoparticles before the addition of doxorubicin did not enhance doxorubicin-induced growth inhibition. Pre-incubation of MCF-7 cells with iron oxide nanoparticles followed by a static magnetic field exposure significantly (P  Conclusions These results might point to the importance of combining magnetic nanoparticles with a static magnetic field in treatment of doxorubicin-refractory breast cancer cells.

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

    Science.gov (United States)

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

    2017-04-15

    The detection of cancer cells through important molecular recognition target such as sialic acid is significant for the clinical diagnosis and treatment. There are many electrochemical cytosensors developed for cancer cells detection but most of them have complicated fabrication processes which results in poor reproducibility and reliability. In this study, a simple, low-cost, and highly sensitive electrochemical cytosensor was designed based on boronic acid-functionalized polythiophene. In cytosensors fabrication simple single-step procedure was used which includes coating pencil graphite electrode (PGE) by means of electro-polymerization of 3-Thienyl boronic acid and Thiophen. Electrochemical impedance spectroscopy and cyclic voltammetry were used as an analytical methods to optimize and measure analytical performances of PGE/P(TBA0.5Th0.5) based electrode. Cytosensor showed extremely good analytical performances in detection of cancer cells with linear rage of 1×10(1) to 1×10(6) cellsmL(-1) exhibiting low detection limit of 10 cellsmL(-1) and incubation time of 10min. Next to excellent analytical performances, it showed high selectivity towards AGS cancer cells when compared to HEK 293 normal cells and bone marrow mesenchymal stem cells (BM-hMSCs). This method is promising for future applications in early stage cancer diagnosis. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Inhibition of the aquaporin 3 water channel increases the sensitivity of prostate cancer cells to cryotherapy

    Science.gov (United States)

    Ismail, M; Bokaee, S; Davies, J; Harrington, K J; Pandha, H

    2009-01-01

    Aquaporins (AQPs) are intrinsic membrane proteins that facilitate selective water and small solute movement across the plasma membrane. In this study, we investigate the role of inhibiting AQPs in sensitising prostate cancer cells to cryotherapy. PC-3 and DU145 prostate cancer cells were cooled to 0, −5 and −10°C. The expression of AQP3 in response to freezing was determined using real-time quantitative polymerase chain reaction (RT–qPCR) and western blot analysis. Aquaporins were inhibited using mercuric chloride (HgCl2) and small interfering RNA (siRNA) duplex, and cell survival was assessed using a colorimetric assay. There was a significant increase in AQP3 expression in response to freezing. Cells treated with AQP3 siRNA were more sensitive to cryoinjury compared with control cells (Pcryotherapy. PMID:19513079

  19. 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.

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

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    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.

  1. 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.

  2. Natural product β-thujaplicin inhibits homologous recombination repair and sensitizes cancer cells to radiation therapy.

    Science.gov (United States)

    Zhang, Lihong; Peng, Yang; Uray, Ivan P; Shen, Jianfeng; Wang, Lulu; Peng, Xiangdong; Brown, Powel H; Tu, Wei; Peng, Guang

    2017-12-01

    Investigation of natural products is an attractive strategy to identify novel compounds for cancer prevention and treatment. Numerous studies have shown the efficacy and safety of natural products, and they have been widely used as alternative treatments for a wide range of illnesses, including cancers. However, it remains unknown whether natural products affect homologous recombination (HR)-mediated DNA repair and whether these compounds can be used as sensitizers with minimal toxicity to improve patients' responses to radiation therapy, a mainstay of treatment for many human cancers. In this study, in order to systematically identify natural products with an inhibitory effect on HR repair, we developed a high-throughput image-based HR repair screening assay and screened a chemical library containing natural products. Among the most interesting of the candidate compounds identified from the screen was β-thujaplicin, a bioactive compound isolated from the heart wood of plants in the Cupressaceae family, can significantly inhibit HR repair. We further demonstrated that β-thujaplicin inhibits HR repair by reducing the recruitment of a key HR repair protein, Rad51, to DNA double-strand breaks. More importantly, our results showed that β-thujaplicin can radiosensitize cancer cells. Additionally, β-thujaplicin sensitizes cancer cells to PARP inhibitor in different cancer cell lines. Collectively, our findings for the first time identify natural compound β-thujaplicin, which has a good biosafety profile, as a novel HR repair inhibitor with great potential to be translated into clinical applications as a sensitizer to DNA-damage-inducing treatment such as radiation and PARP inhibitor. In addition, our study provides proof of the principle that our robust high-throughput functional HR repair assay can be used for a large-scale screening system to identify novel natural products that regulate DNA repair and cellular responses to DNA damage-inducing treatments such as

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

    Directory of Open Access Journals (Sweden)

    Kim Kyu Kwang

    2012-04-01

    Full Text Available Abstract Background 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. Methods 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. Results 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. Conclusions Our data show that TM increases the efficacy of various anticancer drugs in ovarian cancer cells in a ROS-dependent manner.

  4. Establishment of an ’In Vitro Cell-Based System’ to Assay Radiation Sensitivity in Breast Cancer

    Science.gov (United States)

    2008-05-31

    with radio-resistance and others are novel. For example, CLPTM1 is a gene when mutated causes cleft palate but as reported by Folgueira et al with two...there is almost a ten-fold difference in the most IR-sensitive breast cancer cell line (HBL100) and the most IR resistant cell line tested T47D. Our...increases radiation sensitivity in the two breast cancer cell lines tested . Key Research Accomplishments: We have established survival

  5. Interferon-α reduces the gefitinib sensitivity of human non-small cell lung cancer

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    Chi Pan

    2016-09-01

    Full Text Available Aim of the study : Many studies have shown that interferon-α(IFN-α enhances the antiproliferative effect of gefitinib in some solid tumours. We aimed to determine the effect of combining IFN-αwith gefitinib in human non-small cell lung cancer (NSCLC cell lines (A549, H1299, HCC827 with different EGFR and K-Ras gene statuses. Material and methods : An MTT assay was used to assess cell proliferation. Apoptosis was detected by an Annexin V/propidium iodide assay using flow cytometry, and western blotting was used to determine the expression of epidermal growth factor receptor/phosphorylated epidermal growth factor receptor (EGFR/p-EGFR and signal transducers and activators of transcription 3/phosphorylated signal transducers and activators of transcription 3 (STAT3/p-STAT3. Results : There was an additive interaction when gefitinib was combined with IFN-α in all cell lines; however, there was antagonism when gefitinib followed IFN-α pretreatment in three cell lines. Notably, IFN-α pretreatment significantly reduced the gefitinib sensitivity of HCC827 cells. Surprisingly, while IFN-α inhibited STAT3 phosphorylation in cell lines, gefitinib could do so. Conclusions : The results might confirm the hypothesis that IFN-α induces gefitinib sensitivity of NSCLC, and IFN-α inhibits phosphorylation of STAT3, which may be dependent on EGFR signal activation playing a role in the reduction of gefitinib sensitivity after IFN-α treatment in NSCLC cell lines.

  6. Differential sensitivities of bladder cancer cell lines to resveratol are unrelated to its metabolic profile

    Science.gov (United States)

    Li, Hong; Wu, Moli; Ren, Changle; Zhen, Yuhong; Ma, Xiaochi; Diao, Yunpeng; Ma, Xiaodong; Deng, Sa; Liu, Jia

    2017-01-01

    Resveratrol (RV) is a natural polyphenol compound with a wide range of activities, including inhibition of human bladder cancer (HBC) cell growth. Because RV is rapidly metabolized and has poor bioavailability, it is unclear whether the antitumor activity is due to RV or its metabolites. We therefore used liquid chromatography-mass spectroscopy, qRT-PCR, immunocytochemistry and western blotting to evaluate the metabolic profile and biotransformation of RV in the T24 and EJ HBC cell lines. Both T24 and EJ cells generated the same RV metabolite, RV monosulfate (RVS), and both exhibited upregulation of the RV-associated metabolic enzyme SULT1A1 (sulfotransferase). Despite these similarities, T24 cells were more sensitive to RV than EJ cells, yet T24 cells exhibited no sensitivity to an RVS mixture (84.13% RVS). Primary rat bladder epithelial cells showed no adverse effects when exposed to a therapeutic dose (100 μM) of RV. The differences in RV sensitivity between the two HBC cell lines did not reflect differences in the RV metabolic profile or SULT1A1 expression. Because RV exhibited stronger antitumor activity and better safety than RVS, we conclude that RV has significant therapeutic potential for HBC treatment, provided individual differences are considered during clinical research and application. PMID:28178690

  7. Sensitivity of endometrial cancer cells from primary human tumor samples to new potential anticancer peptide lactaptin.

    Science.gov (United States)

    Koval, Olga A; Sakaeva, Galiya R; Fomin, Alexander S; Nushtaeva, Anna A; Semenov, Dmitry V; Kuligina, Elena V; Gulyaeva, Ludmila F; Gerasimov, Alexey V; Richter, Vladimir A

    2015-01-01

    Endometrial carcinoma is the most common gynecologic malignancy which is associated with a poor prognosis when diagnosed at an advanced stage; therefore, the discovery of efficacious new drugs is required to reinforce conventional chemotherapy. Short-term cultures of primary cells from endometrial tumors could be used for testing new anticancer therapeutics as well as for the development of personalized cancer therapy strategy. Here, the antitumor effect of a recombinant analogue of lactaptin (RL2), a new potential anticancer molecule, was examined against primary human endometrial cancer cells. Primary cell cultures of malignant and normal human endometrium were performed by enzymatic digestion of endometrial tissue from biopsy material. Real-time quantitative reverse transcription polymerase chain reaction (RT-PCR) was performed to determine the messenger ribonucleic acid (mRNA) state of estrogen (ERs) and progesterone (PRs) hormone receptors and aromatase (Cyp 19) in cell cultures. Dynamic monitoring of cell adhesion and proliferation was made using the iCELLigence system (ASEA Biosciences). The sensitivity of cell cultures to conventional anticancer drugs and the lactaptin analog was estimated by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay, flow cytometry, and the iCELLligence system. Established short-term primary cultures of endometrial cancer cells were ERα/ERβ/PR-positive and sensitive for RL2. The IC 50 values of doxorubicin and cisplatin were determined for all of the primary cultures designed. KE normal cells displaying low Cyp19 mRNA levels and high ERβ and PR mRNA levels were more resistant to RL2 treatment as well as to cisplatin and doxorubicin. Our results indicate that the recombinant analog of lactaptin, RL2, exerts cytotoxic effects against primary hormone-dependent endometrial tumor cells in vitro with features of apoptosis.

  8. 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.

  9. DTNQ-Pro, a Mimetic Dipeptide, Sensitizes Human Colon Cancer Cells to 5-Fluorouracil Treatment

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    Isabel Gomez-Monterrey

    2013-01-01

    Full Text Available The resistance of growing human colon cancer cells to chemotherapy agents has been correlated to endogenous overexpression of stress proteins including the family of heat shock proteins (HSPs. Previously, we have demonstrated that a quinone-based mimetic dipeptide, named DTNQ-Pro, induced differentiation of growing Caco-2 cells through inhibition of HSP70 and HSP90. In addition, our product induced a HSP27 and vimentin intracellular redistribution. In the present study, we have evaluated whether a decrease of stress proteins induced by DTNQ-Pro in Caco-2 cells could sensitize these cells to treatment with 5-fluorouracil (5-FU cytotoxicity. The pretreatment of Caco-2 with 500 nM of DTNQ-Pro increases lipid peroxidation and decreases expression of p38 mitogen-activated protein kinase (MAPK and FOXO3a. At the same experimental conditions, an increase of the 5-FU-induced growth inhibition of Caco-2 cells was recorded. These effects could be due to enhanced DTNQ-Pro-induced membrane lipid peroxidation that, in turn, causes the sensitization of cancer cells to the cytotoxicity mediated by 5-FU.

  10. Sensitive detection and quantitation of EZH2 expression in cancer cell by an electrochemiluminescent method

    Science.gov (United States)

    Li, Qiang; Zhou, Xiaoming

    2009-08-01

    The polycomb group protein enhancer of zeste homolog 2 (EZH2) regulating cell cycle and functioning as a transcriptional repressor, is overexpressed in several human cancers. Therefore it can be a molecular marker for detection of cancer progression and metastasis. Here the electrochemiluminescence (ECL) assay was developed to detect and quantify the amount of EZH2 mRNA expression in cancer cell. Total mRNA was reverse transcribed into cDNA. The cDNA was amplified using a forward and reverse primer pair which were labeled with biotin and Tris (2, 2-bipyridine) ruthenium (II) (TBR) on the 5' end, respectively. The amplification product was captured on streptavidin coated magnetic beads and then separated using a magnetic field. The TBR labels were reacted with the most efficient coreactant, TPA, on the electrode. Photons were produced and detected by a custom-built ECL system. The housekeeping gene hydroxymethylbilane synthase (HMBS) was used as an approximate reference to quantify the amount of EZH2 mRNA expression, whose primer pairs were labeled the same as EZH2. Result indicated that the EZH2 mRNA was overexpressed in MCF-7 cells relative to normal blood cells. This assay is specific and sensitive and could be used for the clinical diagnosis and prognosis of cancer.

  11. Probenecid as a sensitizer of bisphosphonate-mediated effects in breast cancer cells.

    Science.gov (United States)

    Ebert, Regina; Meissner-Weigl, Jutta; Zeck, Sabine; Määttä, Jorma; Auriola, Seppo; Coimbra de Sousa, Sofia; Mentrup, Birgit; Graser, Stephanie; Rachner, Tilman D; Hofbauer, Lorenz C; Jakob, Franz

    2014-12-11

    Anti-resorptive bisphosphonates (BP) are used for the treatment of osteoporosis and bone metastases. Clinical studies indicated a benefit in survival and tumor relapse in subpopulations of breast cancer patients receiving zoledronic acid, thus stimulating the debate about its anti-tumor activity. Amino-bisphosphonates in nM concentrations inhibit farnesyl pyrophosphate synthase leading to accumulation of isopentenyl pyrophosphate (IPP) and the ATP/pyrophosphate adduct ApppI, which induces apoptosis in osteoclasts. For anti-tumor effects μM concentrations are needed and a sensitizer for bisphosphonate effects would be beneficial in clinical anti-tumor applications. We hypothesized that enhancing intracellular pyrophosphate accumulation via inhibition of probenecid-sensitive channels and transporters would sensitize tumor cells for bisphosphonates anti-tumor efficacy. MDA-MB-231, T47D and MCF-7 breast cancer cells were treated with BP (zoledronic acid, risedronate, ibandronate, alendronate) and the pyrophosphate channel inhibitors probenecid and novobiocin. We determined cell viability and caspase 3/7 activity (apoptosis), accumulation of IPP and ApppI, expression of ANKH, PANX1, ABCC1, SLC22A11, and the zoledronic acid target gene and tumor-suppressor KLF2. Treatment of MDA-MB-231 with BP induced caspase 3/7 activity, with zoledronic acid being the most effective. In MCF-7 and T47D either BP markedly suppressed cell viability with only minor effects on apoptosis. Co-treatment with probenecid enhanced BP effects on cell viability, IPP/ApppI accumulation as measurable in MCF-7 and T47D cells, caspase 3/7 activity and target gene expression. Novobiocin co-treatment of MDA-MB-231 yielded identical results on viability and apoptosis compared to probenecid, rendering SLC22A family members as candidate modulators of BP effects, whereas no such evidence was found for ANKH, ABCC1 and PANX1. In summary, we demonstrate effects of various bisphosphonates on caspase 3

  12. 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.

  13. Growth differentiation factor 15 stimulates rapamycin-sensitive ovarian cancer cell growth and invasion.

    Science.gov (United States)

    Griner, Samantha E; Joshi, Jayashree P; Nahta, Rita

    2013-01-01

    Identification of novel molecular markers and therapeutic targets may improve survival rates for patients with ovarian cancer. In the current study, immunohistochemical (IHC) analysis of two human ovarian tumor tissue arrays showed high staining for GDF15 in a majority of tissues. Exogenous stimulation of ovarian cancer cell lines with recombinant human GDF15 (rhGDF15) or stable over-expression of a GDF15 expression plasmid promoted anchorage-independent growth, increased invasion, and up-regulation of matrix metalloproteinases (MMPs) and vascular endothelial growth factor (VEGF). MMP inhibition suppressed GDF15-mediated invasion. In addition, IHC analysis of human ovarian tumor tissue arrays indicated that GDF15 expression correlated significantly with high MMP2 and MMP9 expression. Exogenous and endogenous GDF15 over-expression stimulated phosphorylation of p38, Erk1/2, and Akt. Pharmacologic inhibition of p38, MEK, or PI3K suppressed GDF15-stimulated growth. Further, proliferation, growth, and invasion of GDF15 stable clones were blocked by rapamycin. IHC analysis demonstrated significant correlation between GDF15 expression and phosphorylation of mTOR. Finally, knockdown of endogenous GDF15 or neutralization of secreted GDF15 suppressed invasion and growth of a GDF15-over-expressing ovarian cancer cell line. These data indicate that GDF15 over-expression, which occurred in a majority of human ovarian cancers, promoted rapamycin-sensitive invasion and growth of ovarian cancer cells. Inhibition of mTOR may be an effective therapeutic strategy for ovarian cancers that over-express GDF15. Future studies should examine GDF15 as a novel molecular target for blocking ovarian cancer progression. Copyright © 2012 Elsevier Inc. All rights reserved.

  14. Inhibition of never in mitosis A (NIMA)-related kinase-4 reduces survivin expression and sensitizes cancer cells to TRAIL-induced cell death.

    Science.gov (United States)

    Park, So Jung; Jo, Doo Sin; Jo, Se-Young; Shin, Dong Woon; Shim, Sangmi; Jo, Yoon Kyung; Shin, Ji Hyun; Ha, Ye Jin; Jeong, Seong-Yun; Hwang, Jung Jin; Kim, Young Sam; Suh, Young-Ah; Chang, Jong Wook; Kim, Jin Cheon; Cho, Dong-Hyung

    2016-10-04

    The tumor necrosis factor-related apoptosis inducing ligand (TRAIL) preferentially induces apoptosis in cancer cells. However, many tumors are resistant to TRAIL-induced apoptosis, and resistance mechanisms are not fully understood. To identify novel regulatory molecules of TRAIL resistance, we screened a siRNA library targeting the human kinome, and NEK4 (NIMA-related kinase-4) was identified. Knockdown of NEK4 sensitized TRAIL-resistant cancer cells and in vivo xenografts to cell death. In contrast, over expression of NEK4 suppressed TRAIL-induced cell death in TRAIL-sensitive cancer cells. In addition, loss of NEK4 resulted in decrease of the anti-apoptotic protein survivin, but an increase in apoptotic cell death. Interestingly, NEK4 was highly upregulated in tumor tissues derived from patients with lung cancer and colon cancer. These results suggest that inhibition of NEK4 sensitizes cancer cells to TRAIL-induced apoptosis by regulation of survivin expression.

  15. 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.

  16. 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

  17. IDO Downregulation Induces Sensitivity to Pemetrexed, Gemcitabine, FK866, and Methoxyamine in Human Cancer Cells

    Science.gov (United States)

    Maleki Vareki, Saman; Chen, Di; Di Cresce, Christine; Ferguson, Peter J.; Figueredo, Rene; Pampillo, Macarena; Rytelewski, Mateusz; Vincent, Mark; Min, Weiping; Zheng, Xiufen; Koropatnick, James

    2015-01-01

    Indoleamine 2,3-dioxygenase-1 (IDO) is an immune regulatory enzyme expressed by most human tumors. IDO levels in tumor cells correlate with increased metastasis and poor patient outcome and IDO is linked to tumor cell resistance to immunotherapy, radiation therapy, and chemotherapy. Knowledge of tumor cell-autonomous effects of IDO, independent of its well-known role in regulating and suppressing anti-tumor immune responses, is limited. Clonal populations of A549 human lung adenocarcinoma cells stably transfected with anti-IDO shRNA or scrambled control shRNA were used to study IDO effects on drug sensitivity and resistance. IFNγ was used to induce IDO in those cells. We show, for the first time, that IDO mediates human tumor cell resistance to the candidate anticancer drugs FK866 (an NAD+ inhibitor), methoxyamine (MX, a base excision repair [BER] inhibitor) and approved anticancer drugs pemetrexed (a folate anti-metabolite) and gemcitabine (a nucleoside analogue), and combined treatment with pemetrexed and MX, in the absence of immune cells. Concurrent knockdown of IDO and thymidylate synthase (TS, a key rate-limiting enzyme in DNA synthesis and repair) sensitizes human lung cancer cells to pemetrexed and 5FUdR to a greater degree than knockdown of either target alone. We conclude that BER in IDO-expressing A549 cells plays a major role in mediating resistance to a range of approved and candidate anticancer drugs. IDO inhibitors are undergoing clinical trials primarily to improve antitumor immune responses. We show that targeting IDO alone or in combination with TS is a potentially valuable therapeutic strategy for cancer treatment, independent of immune activity and in combination with conventional chemotherapy. PMID:26579709

  18. Rhamnolipids elicit the same cytotoxic sensitivity between cancer cell and normal cell by reducing surface tension of culture medium.

    Science.gov (United States)

    Jiang, Lifang; Shen, Chong; Long, Xuwei; Zhang, Guoliang; Meng, Qin

    2014-12-01

    Biosurfactant rhamnolipids have been claimed to show biological activities of inhibiting the proliferation of cancer cells. In this study, the cytotoxicity of rhamnolipids was examined on four cancer cells (HepG2, Caco-2, Hela, MCF-7 cells) and two normal cells (HK-2 cell, primary hepatocyte). Interestingly, both cancer cells and normal cells exhibited similar sensitivities to the addition of rhamnolipids in culture medium, and the cytotoxicity was largely attenuated by the presence of fetal bovine serum (FBS) in culture medium. In correlation of the mono-/di-rhamnolipid cytotoxicity with the surface tension of culture medium, it was found that rhamnolipids triggered cytotoxicity whenever the surface tension of culture medium decreased below 41 mN/m irrespective of the FBS content in culture medium, cell line, or rhamnolipid congener. Similarly, each chemical surfactant (Tween-80, sodium dodecyl sulfate, and sodium dodecyl benzene sulfonate) could cause cytotoxicity on HepG2 cells whenever its addition made the surface tension under 41 mN/m in culture medium with or without the presence of FBS. It seems that rhamnolipids, like chemical surfactants, exhibited cytotoxicity by reducing the surface tension of culture medium rather than by changing its specific molecular structure, which had no selection on tumor cells. This study could offer helps to correct the misleading biological activity of rhamnolipids and to avoid the possible large wastes of time and expenses on developing the applications in antitumor drugs.

  19. Inorganic polyphosphate enhances radio-sensitivity in a human non-small cell lung cancer cell line, H1299.

    Science.gov (United States)

    Tsutsumi, Kaori; Matsuya, Yusuke; Sugahara, Tomoki; Tamura, Manami; Sawada, Satoshi; Fukura, Sagiri; Nakano, Hisashi; Date, Hiroyuki

    2017-06-01

    Inorganic polyphosphate is a linear polymer containing tens to hundreds of orthophosphate residues linked by high-energy phosphoanhydride bonds. Polyphosphate has been recognized as a potent anti-metastasis reagent. However, the molecular mechanism underlying polyphosphate action on cancer cells is poorly understood. In this study, we investigated the involvement of polyphosphate in radio-sensitivity using a human non-small cell lung cancer cell line, H1299. We found that polyphosphate treatment decreases cellular adenosine triphosphate levels, suggesting a disruption of energy metabolism. We also found that the induction of DNA double-strand breaks was enhanced in polyphosphate-treated cells after X-ray irradiation and colony formation assay revealed that cell survival decreased compared with that of the control groups. These findings suggest that polyphosphate is a promising radio-sensitizer for cancer cells. Therefore, we hypothesized that polyphosphate treatment disrupts adenosine triphosphate-mediated energy transfer for cellular survival and DNA repair, thereby reducing the cellular capability to resist X-ray irradiation.

  20. Machine learning prediction of cancer cell sensitivity to drugs based on genomic and chemical properties.

    Directory of Open Access Journals (Sweden)

    Michael P Menden

    Full Text Available Predicting the response of a specific cancer to a therapy is a major goal in modern oncology that should ultimately lead to a personalised treatment. High-throughput screenings of potentially active compounds against a panel of genomically heterogeneous cancer cell lines have unveiled multiple relationships between genomic alterations and drug responses. Various computational approaches have been proposed to predict sensitivity based on genomic features, while others have used the chemical properties of the drugs to ascertain their effect. In an effort to integrate these complementary approaches, we developed machine learning models to predict the response of cancer cell lines to drug treatment, quantified through IC₅₀ values, based on both the genomic features of the cell lines and the chemical properties of the considered drugs. Models predicted IC₅₀ values in a 8-fold cross-validation and an independent blind test with coefficient of determination R² of 0.72 and 0.64 respectively. Furthermore, models were able to predict with comparable accuracy (R² of 0.61 IC50s of cell lines from a tissue not used in the training stage. Our in silico models can be used to optimise the experimental design of drug-cell screenings by estimating a large proportion of missing IC₅₀ values rather than experimentally measuring them. The implications of our results go beyond virtual drug screening design: potentially thousands of drugs could be probed in silico to systematically test their potential efficacy as anti-tumour agents based on their structure, thus providing a computational framework to identify new drug repositioning opportunities as well as ultimately be useful for personalized medicine by linking the genomic traits of patients to drug sensitivity.

  1. 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

  2. Bcl-xL inhibition by molecular-targeting drugs sensitizes human pancreatic cancer cells to TRAIL

    Science.gov (United States)

    Hari, Yoko; Harashima, Nanae; Tajima, Yoshitsugu; Harada, Mamoru

    2015-01-01

    Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) induces apoptosis in various types of cancer cells without damaging normal cells. However, in terms of pancreatic cancer, not all cancer cells are sensitive to TRAIL. In this study, we examined a panel of human pancreatic cancer cell lines for TRAIL sensitivity and investigated the effects of Bcl-2 family inhibitors on their response to TRAIL. Both ABT-263 and ABT-737 inhibited the function of Bcl-2, Bcl-xL, and Bcl-w. Of the nine pancreatic cancer cell lines tested, six showed no or low sensitivity to TRAIL, which correlated with protein expression of Bcl-xL. ABT-263 significantly sensitized four cell lines (AsPC-1, Panc-1, CFPAC-1, and Panc10.05) to TRAIL, with reduced cell viability and increased apoptosis. Knockdown of Bcl-xL, but not Bcl-2, by siRNA transfection increased the sensitivity of AsPC-1 and Panc-1 cells to TRAIL. ABT-263 treatment had no effect on protein expression of Bcl-2, Bcl-xL, or c-FLIPs. In Panc-1 cells, ABT-263 increased the surface expression of death receptor (DR) 5; the NF-κB pathway, but not endoplasmic reticulum stress, participated in the increase. In xenograft mouse models, the combination of TRAIL and ATB-737 suppressed the in vivo tumor growth of AsPC-1 and Panc-1 cells. These results indicate that Bcl-xL is responsible for TRAIL resistance in human pancreatic cancer cells, and that Bcl-2 family inhibitors could represent promising reagents to sensitize human pancreatic cancers in DR-targeting therapy. PMID:26506422

  3. The radiation-sensitizing effect of flavopiridol in the esophageal cancer cell line Eca109.

    Science.gov (United States)

    Yao, Yuan; Shi, Jingbin; Zhang, Zhuo; Zhang, Feng; Ma, Ruilan; Zhao, Yan

    2013-06-01

    Flavopiridol is a cyclin-dependent kinase inhibitor. It has shown an antitumor effect against several cancers. In the present study, the radiation-sensitizing effect of flavopiridol was investigated in an esophageal squamous carcinoma cell line, Eca109. The growth inhibitory rate of Eca109 with flavopiridol was determined using the MTT and the radio-sensitizing rate using clonogenic survival assays. The cell cycle distribution and the rate of apoptosis were measured using flow cytometry. The proteins cyclin D1, ERK/pERK, caspase-3, Bax and Bcl-2 were detected using western blot analysis to elucidate the mechanism of the radiosensitization effect. MTT assay showed that flavopiridol inhibited the survival rate of Eca109 cells and the effect was dose-dependent. Its IC50 was 193.3 nmol/l. The result of the clonogenic survival revealed that flavopiridol enhanced the radiosensitivity of Eca109 cells and the sensitization enhancement ratio (SER) was 1.194 at 0.2×IC50. Moreover, we detected that the cells treated with flavorpiridol were arrested at the G2/M phase and the apoptosis caused by radiation was increased. In addition, the proteins caspase-3 and Bax in cells treated with flavopiridol were upregulated, while cyclin D1 and Bcl-2 were downregulated. In conclusion, flavopiridol may enhance the radiosensitivity of Eca109 cells and the radiosensitizing effect of flavopiridol may be mediated by decreasing the levels of the cyclin D1 protein, thus increasing the percentage of cells at G2/M phase.

  4. Targeting interferon response genes sensitizes aromatase inhibitor resistant breast cancer cells to estrogen-induced cell death.

    Science.gov (United States)

    Choi, Hye Joung; Lui, Asona; Ogony, Joshua; Jan, Rifat; Sims, Peter J; Lewis-Wambi, Joan

    2015-01-15

    Estrogen deprivation using aromatase inhibitors (AIs) is currently the standard of care for postmenopausal women with hormone receptor-positive breast cancer. Unfortunately, the majority of patients treated with AIs eventually develop resistance, inevitably resulting in patient relapse and, ultimately, death. The mechanism by which resistance occurs is still not completely known, however, recent studies suggest that impaired/defective interferon signaling might play a role. In the present study, we assessed the functional role of IFITM1 and PLSCR1; two well-known interferon response genes in AI resistance. Real-time PCR and Western blot analyses were used to assess mRNA and protein levels of IFITM1, PLSCR1, STAT1, STAT2, and IRF-7 in AI-resistant MCF-7:5C breast cancer cells and AI-sensitive MCF-7 and T47D cells. Immunohistochemistry (IHC) staining was performed on tissue microarrays consisting of normal breast tissues, primary breast tumors, and AI-resistant recurrence tumors. Enzyme-linked immunosorbent assay was used to quantitate intracellular IFNα level. Neutralizing antibody was used to block type 1 interferon receptor IFNAR1 signaling. Small interference RNA (siRNA) was used to knockdown IFITM1, PLSCR1, STAT1, STAT2, IRF-7, and IFNα expression. We found that IFITM1 and PLSCR1 were constitutively overexpressed in AI-resistant MCF-7:5C breast cancer cells and AI-resistant tumors and that siRNA knockdown of IFITM1 significantly inhibited the ability of the resistant cells to proliferate, migrate, and invade. Interestingly, suppression of IFITM1 significantly enhanced estradiol-induced cell death in AI-resistant MCF-7:5C cells and markedly increased expression of p21, Bax, and Noxa in these cells. Significantly elevated level of IFNα was detected in AI-resistant MCF-7:5C cells compared to parental MCF-7 cells and suppression of IFNα dramatically reduced IFITM1, PLSCR1, p-STAT1, and p-STAT2 expression in the resistant cells. Lastly, neutralizing antibody

  5. miR-200/ZEB axis regulates sensitivity to nintedanib in non-small cell lung cancer cells.

    Science.gov (United States)

    Nishijima, Nobuhiko; Seike, Masahiro; Soeno, Chie; Chiba, Mika; Miyanaga, Akihiko; Noro, Rintaro; Sugano, Teppei; Matsumoto, Masaru; Kubota, Kaoru; Gemma, Akihiko

    2016-03-01

    Nintedanib (BIBF1120) is a multi-targeted angiokinase inhibitor and has been evaluated in idiopathic pulmonary fibrosis and advanced non-small cell lung cancer (NSCLC) patients in clinical studies. In the present study, we evaluated the antitumor effects of nintedanib in 16 NSCLC cell lines and tried to identify microRNA (miRNA) associated with sensitivity to nintedanib. No correlations between FGFR, PDGFR and VEGFR family activation and sensitivity to nintedanib were found. The difference in miRNA expression profiles between 5 nintedanib-sensitive and 5 nintedanib-resistant cell lines was evaluated by miRNA array and quantitative RT-PCR analysis (qRT-PCR). Expression of miR-200b, miR-200a and miR-141 belonging to the miR-200 family which contributes to epithelial-mesenchymal transition (EMT), was significantly lower in 5 nintedanib-resistant than in 5 nintedanib-sensitive cell lines. We examined the protein expression of EMT markers in these 10 NSCLC cell lines. E-cadherin expression was lower, and vimentin and ZEB1 expression were higher in 5 nintedanib-resistant cell lines. PC-1 was the most sensitive of the NSCLC cell lines to nintedanib. We established nintedanib-resistant PC-1 cells (PC-1R) by the stepwise method. PC-1R cells also showed decreased expression of miR-200b, miR-141 and miR-429 and increased expression of ZEB1 and ZEB2. We confirmed that induction of miR-200b or miR-141 enhanced sensitivity to nintedanib in nintedanib-resistant A549 and PC1-R cells. In addition, we evaluated the response to gefitinib in combination with nintedanib after TGF-β1 exposure of A549 cells. Nintedanib was able to reverse TGF-β1-induced EMT and resistance to gefitinib caused by miR-200b and miR-141 upregulation and ZEB1 downregulation. These results suggested that the miR-200/ZEB axis might be predictive biomarkers for sensitivity to nintedanib in NSCLC cells. Furthermore, nintedanib combined with gefitinib might be a novel therapeutic strategy for NSCLC cells with EMT

  6. Expression of (NES-hTERT in cancer cells delays cell cycle progression and increases sensitivity to genotoxic stress.

    Directory of Open Access Journals (Sweden)

    Olga A Kovalenko

    Full Text Available Telomerase is a reverse transcriptase associated with cellular immortality through telomere maintenance. This enzyme is activated in 90% of human cancers, and inhibitors of telomerase are currently in clinical trials to counteract tumor growth. Many aspects of telomerase biology have been investigated for therapy, particularly inhibition of the enzyme, but little was done regarding its subcellular shuttling. We have recently shown that mutations in the nuclear export signal of hTERT, the catalytic component of telomerase, led to a mutant ((NES-hTERT that failed to immortalize cells despite nuclear localization and catalytic activity. Expression of (NES-hTERT in primary fibroblast resulted in telomere-based premature senescence and mitochondrial dysfunction. Here we show that expression of (NES-hTERT in LNCaP, SQ20B and HeLa cells rapidly and significantly decreases their proliferation rate and ability to form colonies in soft agar while not interfering with endogenous telomerase activity. The cancer cells showed increased DNA damage at telomeric and extra-telomeric sites, and became sensitive to ionizing radiation and hydrogen peroxide exposures. Our data show that expression of (NES-hTERT efficiently counteracts cancer cell growth in vitro in at least two different ways, and suggest manipulation with the NES of hTERT or its subcellular shuttling as a new strategy for cancer treatment.

  7. 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.

  8. Curcumin sensitizes human lung cancer cells to apoptosis and metastasis synergistically combined with carboplatin.

    Science.gov (United States)

    Kang, Ji Ho; Kang, Hye Seon; Kim, In Kyoung; Lee, Hwa Young; Ha, Jick Hwan; Yeo, Chang Dong; Kang, Hyun Hui; Moon, Hwa Sik; Lee, Sang Haak

    2015-11-01

    Although carboplatin is one of the standard chemotherapeutic agents for non-small cell lung cancer (NSCLC), it has limited therapeutic efficacy due to activation of a survival signaling pathway and the induction of multidrug resistance. Curcumin, a natural compound isolated from the plant Curcuma longa, is known to sensitize tumors to different chemotherapeutic agents. The aim of this study is to evaluate whether curcumin can chemosensitize lung cancer cells to carboplatin and to analyze the signaling pathway underlying this synergism. We investigated the synergistic effect of both agents on cell proliferation, apoptosis, invasion, migration, and expression of related signaling proteins using the human NSCLC cell line, A549. A549 cell was treated with different concentrations of curcumin and carboplatin alone and in combination. Combined treatment with curcumin and carboplatin inhibited tumor cell growth, migration, and invasion compared with either drug alone. Matrix metalloproteinase (MMP)-2 and MMP-9 were more efficiently downregulated by co-treatment than by each treatment alone. mRNA and protein expression of caspase-3 and caspase-9 and proapoptotic genes was increased in cells treated with a combination of curcumin and carboplatin, whereas expression of the antiapoptotic Bcl-2 gene was suppressed. Co-treatment of both agents substantially suppressed NF-κB activation and increased expression of p53. Phosphorylation of Akt, a protein upstream of NF-κB, was reduced, resulting in inhibition of the degradation of inhibitor of κB(IκBα), whereas the activity of extracellular signal-regulated kinase (ERK1/2) was enhanced. Our study demonstrated that the synergistic antitumor activity of curcumin combined with carboplatin is mediated by multiple mechanisms involving suppression of NF-κB via inhibition of the Akt/IKKα pathway and enhanced ERK1/2 activity. Based on this mechanism, curcumin has potential as a chemosensitizer for carboplatin in the treatment of

  9. 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.

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

    Science.gov (United States)

    2011-07-01

    defective quiescence is a predisposing factor for breast cancer . Under normal conditions, nulliparous MMTV-myc have a very low incidence of... parity in this model. Such a finding would implicate control of quiescence in breast cancer initiation and would further suggest that mammary stem...AD_________________ Award Number: W81XWH-10-1-0430 TITLE: Targeting Breast Cancer Recurrence via

  11. Influence of the HER receptor ligand system on sensitivity to cetuximab and trastuzumab in gastric cancer cell lines.

    Science.gov (United States)

    Kneissl, Julia; Hartmann, Anja; Pfarr, Nicole; Erlmeier, Franziska; Lorber, Thomas; Keller, Simone; Zwingenberger, Gwen; Weichert, Wilko; Luber, Birgit

    2017-04-01

    Gastric cancer remains a major health concern, and improvement of the therapeutic options is crucial. Treatment with targeted therapeutics such as the EGFR-targeting antibody cetuximab or the HER2-targeting antibody trastuzumab is either ineffective or moderately effective in this disease, respectively. In this study, we analysed the involvement of the HER receptor ligands amphiregulin (AREG), epidermal growth factor (EGF), heparin-binding epidermal growth factor (HB-EGF) and transforming growth factor alpha (TGFα) in the responsiveness of gastric cancer cell lines to cetuximab and trastuzumab. A panel of 11 gastric cancer cell lines was characterized for cetuximab and trastuzumab sensitivity, ligand secretion and expression and activation of the HER receptors using WST-1 cell proliferation assays, ELISAs and Western blot analyses. We further investigated the effects of an exogenous ligand application on the cetuximab and trastuzumab sensitivity. We found no correlation between TGFα secretion and the sensitivity to cetuximab or trastuzumab. For AREG, we confirmed previous results indicating that this ligand is a positive predictor of cetuximab sensitivity. Exogenous HB-EGF was effective in rescuing sensitive cell lines from inhibition of cell proliferation by both, cetuximab and trastuzumab. Our data indicate that HB-EGF may be a useful marker for the prediction of trastuzumab sensitivity in gastric cancer.

  12. Inhibition of MDM2 Re-Sensitizes Rapamycin Resistant Renal Cancer Cells via the Activation of p53.

    Science.gov (United States)

    Tian, Xin; Dai, Shundong; Sun, Jing; Jiang, Shenyi; Sui, Chengguang; Meng, Fandong; Li, Yan; Fu, Liye; Jiang, Tao; Wang, Yang; Su, Jia; Jiang, Youhong

    2016-01-01

    Rapamycin is a potential anti-cancer agent, which modulates the activity of mTOR, a key regulator of cell growth and proliferation. However, several types of cancer cells are resistant to the anti-proliferative effects of rapamycin. In this study, we report a MDM2/p53-mediated rapamycin resistance in human renal cancer cells. Trypan blue exclusion tests were used to determine the cell viability. Changes in mRNA and protein expression were measured using real-time PCR and western blot, respectively. Xenograft models were established to evaluate the in vivo effects of rapamycin combined with a MDM2 inhibitor. Rapamycin treatment suppresses the expression of MDM2 and exogenous overexpression of MDM2 in A498 cells contributes to rapamycin resistance. By establishing a rapamycin resistant cell line, we observed that MDM2 was significantly upregulated in rapamycin resistant cells than that in rapamycin sensitive cells. Importantly, the rapamycin resistant cells demonstrated attenuated accumulation of p53 in the nucleus in response to rapamycin treatment. Moreover, the inhibition of MDM2 by siMDM2 sensitizes A498 cells to rapamycin through the activation of p53. In both in vitro and in vivo models, the combination of rapamycin with the MDM2 inhibitor, MI-319, demonstrated a synergistic inhibitory effect on rapamycin resistant cells. Our study reports a novel mechanism for rapamycin resistance in human renal cancer and provides a new perspective for the development of anti-cancer drugs. © 2016 S. Karger AG, Basel.

  13. 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

  14. The sesquiterpene lactone eupatolide sensitizes breast cancer cells to TRAIL through down-regulation of c-FLIP expression.

    Science.gov (United States)

    Lee, Jongkyu; Hwangbo, Cheol; Lee, Jung Joon; Seo, Juhee; Lee, Jeong-Hyung

    2010-01-01

    Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a promising candidate for cancer therapeutics due to its ability to induce apoptosis selectively in cancer cells. However, sensitivity of cancer cells for induction of apoptosis by TRAIL varies considerably. Therefore, it is important to develop agents that overcome this resistance. We show, for the first time, that eupatolide, the sesquiterpene lactone isolated from the medicinal plant Inula britannica, sensitizes human breast cancer cells to TRAIL-induced apoptosis. Treatment with TRAIL in combination with subtoxic concentrations of eupatolide enhanced the TRAIL-induced cytotoxicity in MCF-7, MDA-MB-231 and MDA-MB-453 breast cancer cells, whereas each reagent alone slightly induced cell death. The combination induced sub-G1 phase DNA content and annexin V-staining in MCF-7 cells, which are major features of apoptosis. Apoptotic characteristics induced by the combined treatment were significantly inhibited by a pan-caspase inhibitor. The sensitization to TRAIL-induced apoptosis was accompanied by the activation of caspase-8 and was concomitant with Bid and poly(ADP-ribose) polymerase (PARP) cleavage. Treatment of eupatolide alone significantly down-regulated the expression of cellular FLICE inhibitory protein (c-FLIP) in MCF-7 cells. Furthermore, enforced expression of c-FLIP significantly attenuated the apoptosis induced by this combination in MCF-7 cells, suggesting a key role for c-FLIP down-regulation in these events. We also observed that euaptolide inhibited AKT phosphorylation in a dose- and time-dependent manner. Moreover, inhibition of Akt by LY294002, a specific PI3K inhibitor, down-regulated c-FLIP expression in MCF-7 cells. Taken together, these results indicate that eupatolide could augment TRAIL-induced apoptosis in human breast cancer cells by down-regulating c-FLIP expression through the inhibition of AKT phosphorylation and be a valuable compound to overcome TRAIL resistance in

  15. 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.

  16. Formulation of Acid-Sensitive Micelles for Delivery of Cabazitaxel into Prostate Cancer Cells.

    Science.gov (United States)

    Aydin, Omer; Youssef, Ibrahim; Yuksel Durmaz, Yasemin; Tiruchinapally, Gopinath; ElSayed, Mohamed E H

    2016-04-04

    We report the synthesis of an amphiphilic triblock copolymer composed of a hydrophilic poly(ethylene glycol) (PEG) block, a central poly(acrylic acid) (PAA) block, and a hydrophobic poly(methyl methacrylate) (PMMA) block using atom transfer radical polymerization technique. We examined the self-assembly of PEG-b-PAA-b-PMMA copolymers in aqueous solutions forming nanosized micelles and their ability to encapsulate hydrophobic guest molecules such as Nile Red (NR) dye and cabazitaxel (CTX, an anticancer drug). We used 2,2β'-(propane-2,2-diylbis(oxy))-diethanamine to react with the carboxylic acid groups of the central PAA block forming acid-labile, shell cross-linked micelles (SCLM). We investigated the loading efficiency and release of different guest molecules from non-cross-linked micelles (NSCLM) and shell cross-linked micelles (SCLM) prepared by reacting 50% (SCLM-50) and 100% (SCLM-100) of the carboxylic acid groups in the PAA in physiologic (pH 7.4) and acidic (pH 5.0) buffer solutions as a function of time. We examined the uptake of NR-loaded NSCLM, SCLM-50, and SCLM-100 micelles into PC-3 and C4-2B prostate cancer cells and the effect of different micelle compositions on membrane fluidity of both cell lines. We also investigated the effect of CTX-loaded NSCLM, SCLM-50, and SCLM-100 micelles on the viability of PC-3 and C4-2B cancer cells compared to free CTX as a function of drug concentration. Results show that PEG-b-PAA-b-PMMA polymers form micelles at concentrations ≥11 μg/mL with an average size of 40-50 nm. CTX was encapsulated in PEG-b-PAA-b-PMMA micelles with 55% loading efficiency in NSCLM. In vitro release studies showed that 30% and 85% of the loaded CTX was released from SCLM-50 micelles in physiologic (pH 7.4) and acidic (pH 5.0) buffer solutions over 30 h, confirming micelles' sensitivity to solution pH. Results show uptake of NSCLM and SCLM into prostate cancer cells delivering their chemotherapeutic cargo, which triggered efficient cancer

  17. 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.

  18. 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.

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

    National Research Council Canada - National Science Library

    Rizvi, N. A; Hellmann, M. D; Snyder, A; Kvistborg, P; Makarov, V; Havel, J. J; Lee, W; Yuan, J; Wong, P; Ho, T. S; Miller, M. L; Rekhtman, N; Moreira, A. L; Ibrahim, F; Bruggeman, C; Gasmi, B; Zappasodi, R; Maeda, Y; Sander, C; Garon, E. B; Merghoub, T; Wolchok, J. D; Schumacher, T. N; Chan, T. A

    2015-01-01

    .... To unravel the genomic determinants of response to this therapy, we used whole-exome sequencing of non-small cell lung cancers treated with pembrolizumab, an antibody targeting programmed cell death-1 (PD-1...

  20. Resistance to cisplatin and paclitaxel does not affect the sensitivity of human ovarian cancer cells to antiprogestin-induced cytotoxicity

    Science.gov (United States)

    2014-01-01

    Background Antiprogestin compounds have been shown to be effective in blocking the growth of ovarian cancer cells of different genetic backgrounds. Herein we studied the anti-ovarian cancer effect of a series of antiprogestins sharing the chemical backbone of the most characterized antiprogestin, mifepristone, but with unique modifications in position C-17 of the steroid ring. We assessed the effect of mifepristone-like antiprogestins on the growth of ovarian cancer cells sensitive to the standard combination therapy cisplatin-paclitaxel or made double-resistant upon six cycles of pulse-selection with the drugs used at clinically relevant concentrations and exposure times. Methods IGROV-1 and SKOV-3 cells were pulsed with 20 μM cisplatin for 1 h followed by 100 nM paclitaxel for 3 h once a week for six weeks. The cells that did not die and repopulate the culture after the chemotherapies were termed Platinum-Taxane-EScape cells (PTES). Parental cells were compared against their PTES derivatives in their responses to further platinum-taxane treatments. Moreover, both ovarian cancer cells and their PTES siblings were exposed to escalating doses of the various antiprogestin derivatives. We assessed cell growth, viability and sub-G1 DNA content using microcapillary cytometry. Cyclin-dependent kinase inhibitors p21cip1 and p27kip1 and cleavage of downstream caspase-3 substrate PARP were used to assess whether cell fate, as a consequence of treatment, was limited to cytostasis or progressed to lethality. Results Cells subjected to six pulse-selection cycles of cisplatin-paclitaxel gave rise to sibling derivatives that displayed ~2-7 fold reduction in their sensitivities to further chemotherapy. However, regardless of the sensitivity the cells developed to the combination cisplatin-paclitaxel, they displayed similar sensitivity to the antiprogestins, which blocked their growth in a dose-related manner, with lower concentrations causing cytostasis, and higher

  1. Smac/DIABLO enhances the therapeutic potential of chemotherapeutic drugs and irradiation, and sensitizes TRAIL-resistant breast cancer cells

    Directory of Open Access Journals (Sweden)

    Srivastava Rakesh K

    2008-06-01

    Full Text Available Abstract Background Drug resistance is a major concern in cancer therapy. Here, we investigate the clinical potential of the second mitochondria-derived activator of caspase (Smac/DIABLO in enhancing the apoptosis-inducing potential of commonly used anticancer drugs (paclitaxel, doxorubicin, etoposide, tamoxifen, irradiation and TRAIL in breast carcinoma. Methods Breast cancer cells were overexpressed with Smac/DIABLO gene (full-length or Δ55 Smac/DIABLO or treated with Smac/DIABLO peptide to enhance the apoptosis-inducing potential of chemotherapeutic drugs and irradiation, and sensitize TRAIL-resistant cells. Cell viability and apoptosis were measured by XTT assay and DAPI staining, respectively. Protein-protein interaction was determined by immunoprecipitation followed by the Western blot analysis. Results Overexpression of Smac/DIABLO gene (full-length or Δ55 Smac/DIABLO or treatment with Smac/DIABLO peptide enhances apoptosis induced by paclitaxel, doxorubicin, etoposide, tamoxifen, and irradiation in breast cancer cells. Overexpression of Smac/DIABLO resulted in an increased interaction of Smac/DIABLO with IAPs, which correlated with an increase in caspase-3 activity and apoptosis. Furthermore, Smac/DIABLO sensitized TRAIL-resistant breast cancer cell lines to undergo apoptosis through caspase-3 activation. These data suggest that apoptotic events down-stream of mitochondria were intact in TRAIL-resistant cells since ectopic expression of Smac/DIABLO or pretreatment of cells with Smac/DIABLO peptide completely restored TRAIL sensitivity. Conclusion The ability of Smac/DIABLO agonists to enhance the apoptosis-inducing potential of chemotherapeutic drugs and irradiation, and sensitize TRAIL-resistant tumor cells suggests that Smac/DIABLO may induce fundamental alterations in cell signaling pathways. Thus, Smac/DIABLO agonists can be used as promising new candidates for cancer treatment by potentiating cytotoxic therapies.

  2. Environment dictates dependence on mitochondrial complex I for NAD+ and aspartate production and determines cancer cell sensitivity to metformin

    OpenAIRE

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

    2016-01-01

    Metformin use is associated with reduced cancer mortality, but how metformin impacts cancer outcomes is controversial. While metformin can act cell autonomously to inhibit tumor growth, the doses of metformin that inhibit proliferation in tissue culture are much higher than what has been described in vivo. Here, we show that environment drastically alters sensitivity to metformin and other complex I inhibitors. We find that complex I supports proliferation by regenerating NAD+, and metformin’...

  3. Telomere shortening sensitizes cancer cells to selected cytotoxic agents: in vitro and in vivo studies and putative mechanisms.

    Directory of Open Access Journals (Sweden)

    Orit Uziel

    Full Text Available BACKGROUND: Telomere/telomerase system has been recently recognized as an attractive target for anticancer therapy. Telomerase inhibition results in tumor regression and increased sensitivity to various cytotoxic drugs. However, it has not been fully established yet whether the mediator of these effects is telomerase inhibition per se or telomere shortening resulting from inhibition of telomerase activity. In addition, the characteristics and mechanisms of sensitization to cytotoxic drugs caused by telomerase inhibition has not been elucidated in a systematic manner. METHODOLOGY/PRINCIPAL FINDINGS: In this study we characterized the relative importance of telomerase inhibition versus telomere shortening in cancer cells. Sensitization of cancer cells to cytotoxic drugs was achieved by telomere shortening in a length dependent manner and not by telomerase inhibition per se. In our system this sensitization was related to the mechanism of action of the cytotoxic drug. In addition, telomere shortening affected also other cancer cell functions such as migration. Telomere shortening induced DNA damage whose repair was impaired after administration of cisplatinum while doxorubicin or vincristine did not affect the DNA repair. These findings were verified also in in vivo mouse model. The putative explanation underlying the phenotype induced by telomere shortening may be related to changes in expression of various microRNAs triggered by telomere shortening. CONCLUSIONS/SIGNIFICANCE: To our best knowledge this is the first study characterizing the relative impact of telomerase inhibition and telomere shortening on several aspects of cancer cell phenotype, especially related to sensitivity to cytotoxic drugs and its putative mechanisms. The microRNA changes in cancer cells upon telomere shortening are novel information. These findings may facilitate the development of telomere based approaches in treatment of cancer.

  4. Eeyarestatin causes cervical cancer cell sensitization to bortezomib treatment by augmenting ER stress and CHOP expression.

    Science.gov (United States)

    Brem, German J; Mylonas, Ioannis; Brüning, Ansgar

    2013-02-01

    The proteasome inhibitor bortezomib is currently being tested in clinical trials against refractory cervical cancer. However, high doses of bortezomib are associated with adverse effects, which may lead to treatment abrogation or to the use of lower, ineffective doses. We investigated combination drug treatments that could enhance the efficacy of low bortezomib concentrations on cervical cancer cells. The cervical cancer cell lines CaSki, HeLa and SW756 were treated with various combinations of bortezomib and eeyarestatin. Treated cells were analyzed for cell viability by clonal assays and the MTT assay, and for expression of pro-apoptotic proteins and cell stress markers by immunofluorescence, immunoblots and RT-PCR analysis. Cotreatment of bortezomib with eeyarestatin markedly enhanced cell death in cervical cancer cells, allowing reduction of the bortezomib concentration necessary for efficient cell death to as low as 5 ng/ml. Combination of bortezomib with eeyarestatin resulted in a massive induction of the endoplasmic reticulum stress reaction, small and large heat shock protein activation, autophagy, and upregulation of pro-apoptotic CHOP. Eeyarestatin is a small molecule recently shown to cause endoplasmic reticulum stress by inhibiting the endoplasmic reticulum-associated degradation pathway, which directs misfolded cytotoxic proteins to proteasomal degradation. Concomitant inhibition of both pathways markedly enhances the efficacy of bortezomib against cervical cancer cells and thus may be applied to reduce the bortezomib dosage required for efficient cervical cancer treatment. Copyright © 2012 Elsevier Inc. All rights reserved.

  5. miR-495 sensitizes MDR cancer cells to the combination of doxorubicin and taxol by inhibiting MDR1 expression.

    Science.gov (United States)

    Zou, Zhenyou; Zou, Ruyi; Zong, Dan; Shi, Yonghong; Chen, Jinyao; Huang, Jie; Zhu, Jiahui; Chen, Liguan; Bao, Xiaoyan; Liu, Yuan; Liu, Weihao; Huang, Wenhui; Hu, Jingsang; Chen, Zhi; Lao, Xiaojie; Chen, Chaoqun; Huang, Xiaoli; Lu, Yao; Ni, Xueyin; Fang, Daoquan; Wu, Dengqiang; Lu, Shuangshuang; Jiang, Mingzhu; Qiu, Chenyang; Wu, Yuya; Qiu, Qisha; Dong, Yanyuan; Su, Yangyang; Zhao, Chenmin; Zhong, Zhihe; Cai, Jing; Liang, Yong

    2017-09-01

    MDR1 is highly expressed in MDR A2780DX5 ovarian cancer cells, MDR SGC7901R gastric cancer cells and recurrent tumours. It pumps cytoplasmic agents out of cells, leading to decreased drug accumulation in cells and making cancer cells susceptible to multidrug resistance. Here, we identified that miR-495 was predicted to target ABCB1, which encodes protein MDR1. To reduce the drug efflux and reverse MDR in cancer cells, we overexpressed a miR-495 mimic in SGC7901R and A2780DX cells and in transplanted MDR ovarian tumours in vivo. The results indicated that the expression of MDR1 in the above cells or tumours was suppressed and that subsequently the drug accumulation in the MDR cells was decreased, cell death was increased, and tumour growth was inhibited after treatment with taxol-doxorubicin, demonstrating increased drug sensitivity. This study suggests that pre-treatment with miR-495 before chemotherapy could improve the curative effect on MDR1-based MDR cancer. © 2017 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

  6. Knockdown of MTDH sensitizes endometrial cancer cells to cell death induction by death receptor ligand TRAIL and HDAC inhibitor LBH589 co-treatment.

    Directory of Open Access Journals (Sweden)

    Xiangbing Meng

    Full Text Available Understanding the molecular underpinnings of chemoresistance is vital to design therapies to restore chemosensitivity. In particular, metadherin (MTDH has been demonstrated to have a critical role in chemoresistance. Over-expression of MTDH correlates with poor clinical outcome in breast cancer, neuroblastoma, hepatocellular carcinoma and prostate cancer. MTDH is also highly expressed in advanced endometrial cancers, a disease for which new therapies are urgently needed. In this present study, we focused on the therapeutic benefit of MTDH depletion in endometrial cancer cells to restore sensitivity to cell death. Cells were treated with a combination of tumor necrosis factor-α-related apoptosis-inducing ligand (TRAIL, which promotes death of malignant cells of the human reproductive tract, and histone deacetylase (HDAC inhibitors, which have been shown to increase the sensitivity of cancer cells to TRAIL-induced apoptosis. Our data indicate that depletion of MTDH in endometrial cancer cells resulted in sensitization of cells that were previously resistant in response to combinatorial treatment with TRAIL and the HDAC inhibitor LBH589. MTDH knockdown reduced the proportion of cells in S and increased cell arrest in G2/M in cells treated with LBH589 alone or LBH589 in combination with TRAIL, suggesting that MTDH functions at the cell cycle checkpoint to accomplish resistance. Using microarray technology, we identified 57 downstream target genes of MTDH, including calbindin 1 and galectin-1, which may contribute to MTDH-mediated therapeutic resistance. On the other hand, in MTDH depleted cells, inhibition of PDK1 and AKT phosphorylation along with increased Bim expression and XIAP degradation correlated with enhanced sensitivity to cell death in response to TRAIL and LBH589. These findings indicate that targeting or depleting MTDH is a potentially novel avenue for reversing therapeutic resistance in patients with endometrial cancer.

  7. 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.

  8. Novel Piperazine-based Compounds Inhibit Microtubule Dynamics and Sensitize Colon Cancer Cells to Tumor Necrosis Factor-induced Apoptosis*

    Science.gov (United States)

    Chopra, Avijeet; Anderson, Amy; Giardina, Charles

    2014-01-01

    We recently identified a series of mitotically acting piperazine-based compounds that potently increase the sensitivity of colon cancer cells to apoptotic ligands. Here we describe a structure-activity relationship study on this compound class and identify a highly active derivative ((4-(3-chlorophenyl)piperazin-1-yl)(2-ethoxyphenyl)methanone), referred to as AK301, the activity of which is governed by the positioning of functional groups on the phenyl and benzoyl rings. AK301 induced mitotic arrest in HT29 human colon cancer cells with an ED50 of ≈115 nm. Although AK301 inhibited growth of normal lung fibroblast cells, mitotic arrest was more pronounced in the colon cancer cells (50% versus 10%). Cells arrested by AK301 showed the formation of multiple microtubule organizing centers with Aurora kinase A and γ-tubulin. Employing in vitro and in vivo assays, tubulin polymerization was found to be slowed (but not abolished) by AK301. In silico molecular docking suggests that AK301 binds to the colchicine-binding domain on β-tubulin, but in a novel orientation. Cells arrested by AK301 expressed elevated levels of TNFR1 on their surface and more readily activated caspases-8, -9, and -3 in the presence of TNF. Relative to other microtubule destabilizers, AK301 was the most active TNF-sensitizing agent and also stimulated Fas- and TRAIL-induced apoptosis. In summary, we report a new class of mitosis-targeting agents that effectively sensitizes cancer cells to apoptotic ligands. These compounds should help illuminate the role of microtubules in regulating apoptotic ligand sensitivity and may ultimately be useful for developing agents that augment the anti-cancer activities of the immune response. PMID:24338023

  9. 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.

  10. 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.

  11. [Effects of RNA interference silencing RhoC gene upon paclitaxel sensitivity in ovarian cancer cell lines].

    Science.gov (United States)

    Pan, Ying; Zhang, Wen-ying; Zou, Ji-yan; Sheng, Min-jia; Xuan, Li-li; Hai, De-yang

    2009-06-02

    To explore the changes of paclitaxel sensitivity by RNA interference of RhoC gene in ovarian cancer cell lines. The microRNA (miRNA) targeting RhoC gene was designed and synthesized by in vitro transcription and transfected into ovarian cancer cell line SKOV3. The mRNA and protein of RhoC were detected by the means of RT-PCR and Western blot. The changes of paclitaxel sensitivity after interference were examined by methyl thiazolyl tetrazolium (MTf) assay. At the same time, the mRNA of apoptosis gene Caspase-3 and survivin were evaluated by RT-PCR. In SKOV3 cell, the mRNA and protein of RhoC dramatically decreased at 24, 48 and 72 hours post-transfection. The sensitivity of SKOV3 cell line to paclitaxel increased significantly after turning off the RhoC gene. The proapoptotic gene Caspase-3 increased significantly and anti-apoptosis gene survivin dramatically decreased after the combination treatment of paclitaxel and RhoC-miRNA in comparison with paclitaxel alone treatment. The sensitivity of ovarian cancer cell lines SKOV3 to paclitaxel can be enhanced by RNA interfering RhoC gene. The synergistic mechanism is possibly correlated with the up-regulation of Caspase-3 gene and the down-regulation of survivin gene.

  12. Bay 61-3606 Sensitizes TRAIL-Induced Apoptosis by Downregulating Mcl-1 in Breast Cancer Cells.

    Directory of Open Access Journals (Sweden)

    So-Young Kim

    Full Text Available Breast cancer cells generally develop resistance to TNF-Related Apoptosis-Inducing Ligand (TRAIL and, therefore, assistance from sensitizers is required. In our study, we have demonstrated that Spleen tyrosine kinase (Syk inhibitor Bay 61-3606 was identified as a TRAIL sensitizer. Amplification of TRAIL-induced apoptosis by Bay 61-3606 was accompanied by the strong activation of Bak, caspases, and DNA fragmentation. In mechanism of action, Bay 61-3606 sensitized cells to TRAIL via two mechanisms regulating myeloid cell leukemia sequence-1 (Mcl-1. First, Bay 61-3606 triggered ubiquitin-dependent degradation of Mcl-1 by regulating Mcl-1 phosphorylation. Second, Bay 61-3606 downregulates Mcl-1 expression at the transcription level. In this context, Bay 61-3606 acted as an inhibitor of Cyclin-Dependent Kinase (CDK 9 rather than Syk. In summary, Bay 61-3606 downregulates Mcl-1 expression in breast cancer cells and sensitizes cancer cells to TRAIL-mediated apoptosis.

  13. Differential contributory roles of nucleotide excision and homologous recombination repair for enhancing cisplatin sensitivity in human ovarian cancer cells

    Directory of Open Access Journals (Sweden)

    Wani Gulzar

    2011-03-01

    Full Text Available Abstract Background While platinum-based chemotherapeutic agents are widely used to treat various solid tumors, the acquired platinum resistance is a major impediment in their successful treatment. Since enhanced DNA repair capacity is a major factor in conferring cisplatin resistance, targeting of DNA repair pathways is an effective stratagem for overcoming cisplatin resistance. This study was designed to delineate the role of nucleotide excision repair (NER, the principal mechanism for the removal of cisplatin-induced DNA intrastrand crosslinks, in cisplatin resistance and reveal the impact of DNA repair interference on cisplatin sensitivity in human ovarian cancer cells. Results We assessed the inherent NER efficiency of multiple matched pairs of cisplatin-sensitive and -resistant ovarian cancer cell lines and their expression of NER-related factors at mRNA and protein levels. Our results showed that only the cisplatin-resistant ovarian cancer cell line PEO4 possessed an increased NER capacity compared to its inherently NER-inefficient parental line PEO1. Several other cisplatin-resistant cell lines, including CP70, CDDP and 2008C13, exhibited a normal and parental cell-comparable NER capacity for removing cisplatin-induced DNA intrastrand cross-links (Pt-GG. Concomitant gene expression analysis revealed discordance in mRNA and protein levels of NER factors in various ovarian cancer cell lines and NER proteins level were unrelated to the cisplatin sensitivity of these cell lines. Although knockdown of NER factors was able to compromise the NER efficiency, it only caused a minimal effect on cisplatin sensitivity. On the contrary, downregulation of BRCA2, a critical protein for homologous recombination repair (HRR, significantly enhanced the efficacy of cisplatin in killing ovarian cancer cell line PEO4. Conclusion Our studies indicate that the level of NER factors in ovarian cancer cell lines is neither a determinant of their NER capacity nor

  14. Increased sensitivity of African American triple negative breast cancer cells to nitric oxide-induced mitochondria-mediated apoptosis.

    Science.gov (United States)

    Martinez, Luis; Thames, Easter; Kim, Jinna; Chaudhuri, Gautam; Singh, Rajan; Pervin, Shehla

    2016-07-29

    Breast cancer is a complex heterogeneous disease where many distinct subtypes are found. Younger African American (AA) women often present themselves with aggressive form of breast cancer with unique biology which is very difficult to treat. Better understanding the biology of AA breast tumors could lead to development of effective treatment strategies. Our previous studies indicate that AA but not Caucasian (CA) triple negative (TN) breast cancer cells were sensitive to nitrosative stress-induced cell death. In this study, we elucidate possible mechanisms that contribute to nitric oxide (NO)-induced apoptosis in AA TN breast cancer cells. Breast cancer cells were treated with various concentrations of long-acting NO donor, DETA-NONOate and cell viability was determined by trypan blue exclusion assay. Apoptosis was determined by TUNEL and caspase 3 activity as well as changes in mitochondrial membrane potential. Caspase 3 and Bax cleavage, levels of Cu/Zn superoxide dismutase (SOD) and Mn SOD was assessed by immunoblot analysis. Inhibition of Bax cleavage by Calpain inhibitor, and levels of reactive oxygen species (ROS) as well as SOD activity was measured in NO-induced apoptosis. In vitro and in vivo effect of NO treatment on mammary cancer stem cells (MCSCs) was assessed. NO induced mitocondria-mediated apoptosis in all AA but not in CA TN breast cancer cells. We found significant TUNEL-positive cells, cleavage of Bax and caspase-3 activation as well as depolarization mitochondrial membrane potential only in AA TN breast cancer cells exposed to NO. Inhibition of Bax cleavage and quenching of ROS partially inhibited NO-induced apoptosis in AA TN cells. Increase in ROS coincided with reduction in SOD activity in AA TN breast cancer cells. Furthermore, NO treatment of AA TN breast cancer cells dramatically reduced aldehyde dehydrogenase1 (ALDH1) expressing MCSCs and xenograft formation but not in breast cancer cells from CA origin. Ethnic differences in breast

  15. Inhibition of glutamate cysteine ligase activity sensitizes human breast cancer cells to the toxicity of 2-deoxy-D-glucose.

    Science.gov (United States)

    Andringa, Kelly K; Coleman, Mitchell C; Aykin-Burns, Nukhet; Hitchler, Michael J; Walsh, Susan A; Domann, Frederick E; Spitz, Douglas R

    2006-02-01

    It has been hypothesized that cancer cells increase glucose metabolism to protect against metabolic fluxes of hydroperoxides via glutathione-dependent peroxidases. 2-Deoxy-D-glucose, inhibits glucose metabolism and has been shown to cause cytotoxicity in cancer cells that is partially mediated by disruptions in thiol metabolism. In the current study, human breast cancer cells were continuously treated (24 hours) with 2-deoxy-D-glucose, and total glutathione content as well as the expression of the first enzyme in the glutathione synthetic pathway [glutamate cysteine ligase (GCL)] were found to be induced 2.0-fold. Inhibiting GCL activity during 2-deoxy-D-glucose exposure using l-buthionine-[S,R]-sulfoximine (BSO) significantly enhanced the cytotoxic effects of 2-deoxy-D-glucose and caused increases in endpoints indicative of oxidative stress, including % oxidized glutathione and steady-state levels of pro-oxidants as assayed using an oxidation-sensitive fluorescent probe. These results show that treatment of human breast cancer cells with 2-deoxy-d-glucose causes metabolic oxidative stress that is accompanied by increases in steady-state levels of GCL mRNA, GCL activity, and glutathione content. Furthermore, inhibition of 2-deoxy-D-glucose-mediated induction of GCL activity with BSO increases endpoints indicative of oxidative stress and sensitizes cancer cells to 2-deoxy-D-glucose-induced cytotoxicity. These results support the hypothesis that drug combinations capable of inhibiting both glucose and hydroperoxide metabolism may provide an effective biochemical strategy for sensitizing human cancer cells to metabolic oxidative stress.

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

    Science.gov (United States)

    2011-07-01

    Cell 2008; 2:461-71; PMID:18462696; DOI:10.1016/j. stem.2008.03.001. 45. Diehn M, Cho RW, Lobo NA, Kalisky T, Dorie MJ, Kulp AN, et al. Association of...gad.1484707. 35. Buono KD, Robinson GW, Martin C, Shi S, Stanley P, Tanigaki K, et al. The canonical Notch/RBP-J signaling pathway controls the

  17. Elevated cyclin A associated kinase activity promotes sensitivity of metastatic human cancer cells to DNA antimetabolite drug.

    Science.gov (United States)

    Wang, Jin; Yin, Hailin; Panandikar, Ashwini; Gandhi, Varsha; Sen, Subrata

    2015-08-01

    Drug resistance is a major obstacle in successful systemic therapy of metastatic cancer. We analyzed the involvement of cell cycle regulatory proteins in eliciting response to N (phosphonoacetyl)-L-aspartate (PALA), an inhibitor of de novo pyrimidine synthesis, in two metastatic variants of human cancer cell line MDA-MB-435 isolated from lung (L-2) and brain (Br-1) in nude mouse, respectively. L-2 and Br-l cells markedly differed in their sensitivity to PALA. While both cell types displayed an initial S phase delay/arrest, Br-l cells proliferated but most L-2 cells underwent apoptosis. There was distinct elevation in cyclin A, and phosphorylated Rb proteins concomitant with decreased expression of bcl-2 protein in the PALA treated L-2 cells undergoing apoptosis. Markedly elevated cyclin A associated and cdk2 kinase activities together with increased E2F1-DNA binding were detected in these L-2 cells. Induced ectopic cyclin A expression sensitized Br-l cells to PALA by activating an apoptotic pathway. Our findings demonstrate that elevated expression of cyclin A and associated kinase can activate an apoptotic pathway in cells exposed to DNA antimetabolites. Abrogation of this pathway can lead to resistance against these drugs in metastatic variants of human carcinoma cells.

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

    OpenAIRE

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

    2012-01-01

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

  19. 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.

  20. Inhibition of the sodium potassium adenosine triphosphatase pump sensitizes cancer cells to anoikis and prevents distant tumor formation.

    Science.gov (United States)

    Simpson, Craig D; Mawji, Imtiaz A; Anyiwe, Kika; Williams, Moyo A; Wang, Xiaoming; Venugopal, Amudha L; Gronda, Marcela; Hurren, Rose; Cheng, Sonia; Serra, Stefano; Beheshti Zavareh, Reza; Datti, Alessandro; Wrana, Jeffrey L; Ezzat, Shereen; Schimmer, Aaron D

    2009-04-01

    Normal epithelial cells undergo apoptosis upon detachment from the extracellular matrix, a process termed "anoikis." However, malignant epithelial cells with metastatic potential resist anoikis and can survive in an anchorage-independent fashion. Molecules that sensitize resistant cells to anoikis will be useful chemical probes to understand this pathway. To identify novel anoikis sensitizers in anoikis-resistant PPC-1 prostate adenocarcinoma cells, a library of 2,000 off-patent drugs and natural products was screened for their ability to preferentially induce cell death in suspension over adherent culture conditions. This screen identified five members of the family of cardiac glycosides as anoikis sensitizers, including ouabain, peruvoside, digoxin, digitoxin, and strophanthidin. We conducted further studies with ouabain to discern the mechanism of cardiac glycoside-induced anoikis sensitization. Ouabain initiated anoikis through the mitochondrial pathway of caspase activation. In addition, ouabain sensitized cells to anoikis by inhibiting its known target, the Na(+)/K(+) ATPase pump, and inducing hypoosmotic stress. Resistance to anoikis permits cancer cells to survive in the circulation and facilitates their metastasis to distant organs, so we tested the effects of Na(+)/K(+) ATPase inhibition on distant tumor formation in mouse models. In these mouse models, ouabain inhibited tumor metastases but did not alter the growth of subcutaneous tumors. Thus, we have identified a novel mechanism to sensitize resistant cells to anoikis and decrease tumor metastasis. These results suggest a potential mechanism for the observed clinical reduction in metastasis and relapse in breast cancer patients who have undergone treatments with cardiac glycosides.

  1. Optical imaging of radiation-induced metabolic changes in radiation-sensitive and resistant cancer cells

    Science.gov (United States)

    Alhallak, Kinan; Jenkins, Samir V.; Lee, David E.; Greene, Nicholas P.; Quinn, Kyle P.; Griffin, Robert J.; Dings, Ruud P. M.; Rajaram, Narasimhan

    2017-06-01

    Radiation resistance remains a significant problem for cancer patients, especially due to the time required to definitively determine treatment outcome. For fractionated radiation therapy, nearly 7 to 8 weeks can elapse before a tumor is deemed to be radiation-resistant. We used the optical redox ratio of FAD/(FAD+NADH) to identify early metabolic changes in radiation-resistant lung cancer cells. These radiation-resistant human A549 lung cancer cells were developed by exposing the parental A549 cells to repeated doses of radiation (2 Gy). Although there were no significant differences in the optical redox ratio between the parental and resistant cell lines prior to radiation, there was a significant decrease in the optical redox ratio of the radiation-resistant cells 24 h after a single radiation exposure (p=0.01). This change in the redox ratio was indicative of increased catabolism of glucose in the resistant cells after radiation and was associated with significantly greater protein content of hypoxia-inducible factor 1 (HIF-1α), a key promoter of glycolytic metabolism. Our results demonstrate that the optical redox ratio could provide a rapid method of determining radiation resistance status based on early metabolic changes in cancer cells.

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

    Science.gov (United States)

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

    2016-11-08

    Metformin use is associated with reduced cancer mortality, but how metformin impacts cancer outcomes is controversial. Although metformin can act on cells autonomously to inhibit tumor growth, the doses of metformin that inhibit proliferation in tissue culture are much higher than what has been described in vivo. Here, we show that the environment drastically alters sensitivity to metformin and other complex I inhibitors. We find that complex I supports proliferation by regenerating nicotinamide adenine dinucleotide (NAD)+, and metformin's anti-proliferative effect is due to loss of NAD+/NADH homeostasis and inhibition of aspartate biosynthesis. However, complex I is only one of many inputs that determines the cellular NAD+/NADH ratio, and dependency on complex I is dictated by the activity of other pathways that affect NAD+ regeneration and aspartate levels. This suggests that cancer drug sensitivity and resistance are not intrinsic properties of cancer cells, and demonstrates that the environment can dictate sensitivity to therapies that impact cell metabolism. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. 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.

  4. Growth differentiation factor 15 stimulates rapamycin-sensitive ovarian cancer cell growth and invasion

    OpenAIRE

    Griner, Samantha E.; Joshi, Jayashree P.; Nahta, Rita

    2013-01-01

    Identification of novel molecular markers and therapeutic targets may improve survival rates for patients with ovarian cancer. In the current study, immunohistochemical (IHC) analysis of two human ovarian tumor tissue arrays showed high staining for GDF15 in a majority of tissues. Exogenous stimulation of ovarian cancer cell lines with recombinant human GDF15 (rhGDF15) or stable overexpression of a GDF15 expression plasmid promoted anchorage-independent growth, increased invasion, and up-regu...

  5. 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.

  6. Nicotinamide sensitizes human breast cancer cells to the cytotoxic effects of radiation and cisplatin.

    Science.gov (United States)

    Domínguez-Gómez, G; Díaz-Chávez, J; Chávez-Blanco, A; Gonzalez-Fierro, A; Jiménez-Salazar, J E; Damián-Matsumura, P; Gómez-Quiroz, L E; Dueñas-González, A

    2015-02-01

    Poly(ADP-ribose) polymerase (PARP) inhibitors enhance the effect of DNA alkylating agents on BRCA1‑ and BRCA2-deficient cell lines. The aim of this study was to analyze the effect of the PARP inhibitor nicotinamide (NAM) on breast cancer cells with different BRCA1 expression or function, such as BRCA1‑deficient MDA-MB-436 cells, low expression BRCA1 MCF-7 cells, and the BRCA1 wild‑type MDA-MB-231 cells, to demonstrate its effects as a chemo‑ or radiosensitizing agent. PARP activity was analyzed in MDA-MB-436, MCF-7 and MDA-MB-231 breast cancer cells subjected or not to NAM. Inhibition of PARP by NAM in the presence of DNA damage was examined by Alexa Fluor 488 immunofluorescence. Crystal violet assays were used to test growth inhibition and the chemo‑ and radiosensitization effects of NAM were investigated using clonogenic assays. Significant differences among data sets were determined using two-tailed ANOVA and Bonferroni tests. We demonstrated that NAM reduces PARP activity in vitro, and in cells subjected or not to DNA damage, it also reduces the viability of breast cancer cell lines and synergyzes the cytotoxicity of cisplatin in MDA-MB-436 and MCF-7 cells. Downregulation of PARP1 with siRNA led to modest growth inhibition, which was further increased by cisplatin. Nicotinamide also induced radiosensitization in MDA-MB-436 and MDA-MB-231 cells. In conclusion, NAM may be used as a chemo‑ or radiosensitizing agent regardless of the BRCA1 status in breast cancer.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-01-17

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

  8. 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.

  9. 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

    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...

  10. 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.

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

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    Suwit Duangmano

    2012-01-01

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

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

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

    2008-01-01

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

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

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

    2012-04-01

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

  14. The Effects of Selected Sesquiterpenes from Myrica rubra Essential Oil on the Efficacy of Doxorubicin in Sensitive and Resistant Cancer Cell Lines

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    Martin Ambrož

    2017-06-01

    Full Text Available β-caryophyllene oxide (CAO, α-humulene (HUM, trans-nerolidol (NER and valencene (VAL are constituents of the essential oil of Myrica rubra (MEO, which has significant antiproliferative effect in various cancer cell lines. In the present study, we compared the antiproliferative effect of these sesquiterpenes alone and in combination with the cytostatic drug doxorubicin (DOX in cancer cell lines with different sensitivity to DOX. Two ovarian cancer cell lines (sensitive A2780 and partly resistant SKOV3 and two lymphoblast cancer cell lines (sensitive CCRF/CEM and completely resistant CEM/ADR were used. The observed effects varied among sesquiterpenes and also differed in individual cell lines, with only VAL being effective in all the cell lines. A strong synergism of DOX with NER was found in the A2780 cells, while DOX acted synergistically with HUM and CAO in the SKOV3 cells. In the CCRF/CEM cells, a synergism of DOX with CAO and NER was observed. In resistant CEM/ADR cells, sesquiterpenes did not increase DOX efficacy, although they significantly increased accumulation of DOX (up to 10-times and rhodamine-123 (substrate of efflux transporter ABCB1 within cancer cells. In conclusion, the tested sesquiterpenes were able to improve DOX efficacy in the sensitive and partly resistant cancer cells, but not in cells completely resistant to DOX.

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

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    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

  16. 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.

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

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    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.

  18. Loss of ARID1A expression sensitizes cancer cells to PI3K- and AKT-inhibition

    Science.gov (United States)

    Samartzis, Eleftherios P; Gutsche, Katrin; Dedes, Konstantin J; Fink, Daniel; Stucki, Manuel; Imesch, Patrick

    2014-01-01

    ARID1A mutations are observed in various tumors, including ovarian clear cell (OCCC) and endometrioid carcinomas, endometrial, and breast carcinomas. They commonly result in loss of ARID1A-protein expression and frequently co-occur with PI3K/AKT-pathway activating mechanisms. The aim of this study was to test the hypothesis as to whether PI3K/AKT-pathway activation is a critical mechanism in ARID1A-mutated tumors and if consequently ARID1A-deficient tumors show increased sensitivity to treatment with PI3K- and AKT-inhibitors. Upon ARID1A knockdown, MCF7 breast cancer cells and primary MRC5 cells exhibited a significantly increased sensitivity towards the AKT-inhibitors MK-2206 and perifosine, as well as the PI3K-inhibitor buparlisib. Knockdown of ARID1A in MCF7 led to an increase of pAKT-Ser473. AKT-inhibition with MK-2206 led to increased apoptosis and to a decrease of pS6K in ARID1A-depleted MCF7 cells but not in the controls. In five OCCC cell lines ARID1A-deficiency correlated with increased pAKT-Ser473 levels and with sensitivity towards treatment with the AKT-inhibitor MK-2206. In conclusion, ARID1A-deficient cancer cells demonstrate an increased sensitivity to treatment with small molecule inhibitors of the PI3K/AKT-pathway. These findings suggest a specific requirement of the PI3K/AKT pathway in ARID1A-deficient tumors and reveal a synthetic lethal interaction between loss of ARID1A expression and inhibition of the PI3K/AKT pathway. PMID:24979463

  19. Knockdown of FUSE binding protein 1 enhances the sensitivity of epithelial ovarian cancer cells to carboplatin.

    Science.gov (United States)

    Zhang, Jinli; Xiong, Xifeng; Hua, Xing; Cao, Wenjuan; Qin, Shengnan; Dai, Libing; Liang, Peihong; Zhang, Huiling; Liu, Zhihe

    2017-11-01

    Epithelial ovarian cancer (EOC) affects almost 25,000 women annually and is the fifth most common malignancy in women in North America. A combination of surgery and cytotoxic chemotherapy may produce a favorable clinical response. The platinum-paclitaxel combination regimen is the chemotherapy gold-standard for advanced ovarian cancer, and carboplatin is one of the agents in this combination therapy. However, the majority of patients eventually experience a relapse due to the development of platinum resistance. FUSE binding protein 1 (FBP1) has been identified as an anti-apoptotic and pro-proliferative oncoprotein that is overexpressed in hepatocellular carcinoma. Its high expression is also associated with carboplatin resistance. In the present study, it was identified that the expression of FBP1 was significantly higher in EOC tissues than in normal epithelial ovarian or in epithelial ovarian adenoma tissue. FBP1 expression was significantly correlated with the grade of epithelial ovarian cancer. Carboplatin inhibited the expression of FBP1 in epithelial ovarian cancer cells and the knockdown of FBP1 enhanced the inhibition of cell viability and migration by carboplatin. In addition to FBP1, carboplatin also inhibited the expression of β-catenin and matrix metalloproteinase (MMP)-9. Furthermore, the expression of β-catenin and MMP-9 were lower in FBP1 knockdown cells compared with control EOC cells. FBP1 may thus serve a role in the regulation of the expression of β-catenin and MMP-9; the inhibition of β-catenin and MMP-9 by carboplatin may be mediated through the inhibition of FBP1. The inhibition of FBP1 expression by carboplatin may be a mechanism in the treatment of EOC by carboplatin.

  20. MHP-1 inhibits cancer metastasis and restores topotecan sensitivity via regulating epithelial-mesenchymal transition and TGF-β signaling in human breast cancer cells.

    Science.gov (United States)

    Lin, Sensen; Lyu, Xiaodan; Yu, Jun; Sun, Li; Du, Danyu; Lai, Yanqi; Li, Hongyang; Wang, Ying; Zhang, Luyong; Yin, Hongping; Yuan, Shengtao

    2016-09-15

    Cordyceps has long been used to treat cancer. However, its pharmacologically active components as well as the molecular mechanisms underlying its effects are still unclear. To investigate the effect of MHP-1, a newly isolated polysaccharide from Mortierella hepialid (the asexual structure of C. sinensis), on breast cancer metastasis. The effect of MHP-1 on breast cancer cell migration, epithelial-mesenchymal transition (EMT) and TGF-β signaling were investigated in vitro and in vivo. The effect of MHP-1 against topotecan-resistant MCF-7 cells that developed an EMT-like phenotype was also examined. The in vitro effect of MHP-1 on breast cancer cell proliferation and migration was evaluated by CCK8 and transwell assay. Morphological changes were observed and EMT markers were detected by western blot. The production of MMPs was measured by quantitative PCR and ELISA assay. To further investigate the mechanism that MHP-1 inhibited breast cancer EMT, western blot, ELISA, luciferase reporter gene assay, siRNA, quantitative PCR, immunohistochemistry, and xenograft tumor model were performed. MHP-1 inhibited breast cancer cell migration but did not cause any cytotoxicity. MHP-1 significantly surpressed breast cancer EMT, and slightly decreased MMP-9 secretion. TGF-β signaling was selectively inhibited after MHP-1 treatment, and other EMT-related pathways, like Wnt and Notch, were not affected. MHP-1 reduced the secretion of TGF-β1, but rarely affected other EMT-induced cytokines. Dual luciferase assay and Smad2/3 phosphorylation analysis indicated that MHP-1 suppressed TGF-β signaling. We further showed that MHP-1 restored sensitivity in topotecan (TPT)-resistant MCF-7 cells that developed an EMT-like phenotype. Similarly, the effect of TPT on resistant MCF-7 cells was also increased either by ALK5 (TGFβRI) siRNA or by a small molecular inhibitor of ALK5, SB-431542. MHP-1 inhibited breast cancer metastasis in the MDA-MB-231 xenograft model, and the immunohistochemical

  1. Environmental cystine drives glutamine anaplerosis and sensitizes cancer cells to glutaminase inhibition

    Science.gov (United States)

    Muir, Alexander; Danai, Laura V; Gui, Dan Y; Waingarten, Chiara Y; Lewis, Caroline A

    2017-01-01

    Many mammalian cancer cell lines depend on glutamine as a major tri-carboxylic acid (TCA) cycle anaplerotic substrate to support proliferation. However, some cell lines that depend on glutamine anaplerosis in culture rely less on glutamine catabolism to proliferate in vivo. We sought to understand the environmental differences that cause differential dependence on glutamine for anaplerosis. We find that cells cultured in adult bovine serum, which better reflects nutrients available to cells in vivo, exhibit decreased glutamine catabolism and reduced reliance on glutamine anaplerosis compared to cells cultured in standard tissue culture conditions. We find that levels of a single nutrient, cystine, accounts for the differential dependence on glutamine in these different environmental contexts. Further, we show that cystine levels dictate glutamine dependence via the cystine/glutamate antiporter xCT/SLC7A11. Thus, xCT/SLC7A11 expression, in conjunction with environmental cystine, is necessary and sufficient to increase glutamine catabolism, defining important determinants of glutamine anaplerosis and glutaminase dependence in cancer. PMID:28826492

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

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    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.

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

    Science.gov (United States)

    Smirnova, Alexandra; Gamba, Riccardo; Khoriauli, Lela; Vitelli, Valerio; Nergadze, Solomon G; Giulotto, Elena

    2013-01-01

    Mammalian telomeres are transcribed into long non-coding telomeric repeat-containing RNA (TERRA) molecules 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). 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.

  4. Proteomic profiling of Trastuzumab (Herceptin(R))-sensitive and -resistant SKBR-3 breast cancer cells.

    Science.gov (United States)

    DI Cara, Gianluca; Marengo, Germana; Albanese, Nadia Ninfa; Marabeti, Maria Rita; Musso, Rosa; Cancemi, Patrizia; Pucci-Minafra, Ida

    2013-02-01

    The Human Epidermal Growth Factor Receptor 2 (HER-2), overexpressed in 25-30% of breast carcinomas (BC), is the therapeutic target for trastuzumab, a recombinant humanized monoclonal antibody. The initial response to trastuzumab is often followed by drug-insensitivity within one year. Several hypotheses have been raised to explain this event, but the mechanisms behind the responses to trastuzumab are still unclear. To study the effects of short and prolonged trastuzumab treatment on the proteomic profiles of HER-2-overexpressing SKBR-3 BC cells. Cells were treated with trastuzumab to obtain sensitive and resistant clones. The drug effects were evaluated at the phenotypical and proteomic levels. In the trastuzumab-resistant cells the expression of a large amount of proteins, initially affected by treatment, reverted to levels of the untreated cells. The results obtained so far illustrate for the first time a large-scale differential protein expression between trastuzumab-treated and untreated cells, and between trastuzumab-sensitive and resistant cells. We believe that the results obtained will help to increase the knowledge of the molecular effects of trastuzumab and will be useful to better-understand the drug resistance mechanisms.

  5. 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

  6. Kanglaite sensitizes colorectal cancer cells to Taxol via NF-κΒ inhibition and connexin 43 upregulation.

    Science.gov (United States)

    Wang, Yijia; Zhang, Chunze; Zhang, Shiwu; Zhao, Zhenying; Wang, Jiawen; Song, Jiali; Wang, Yue; Liu, Jun; Hou, Shaobin

    2017-04-28

    Taxol, a first-line anti-tumour drug, has low effectiveness against colorectal cancer. Combination with other agents is an effective strategy to enhance Taxol cytotoxicity. Kanglaite injection is an extract from Coix lacryma-jobi seed and is usually combined with other agents to treat cancer. The aim of this study was to investigate the treatment effect of Taxol combined with Kanglaite on colorectal cancer cell lines. Kanglaite pretreatment followed by Taxol treatment was found to show the best synergism among all combination strategies. This combination also resulted in the smallest tumour volume in a Balb/c mice model. Kanglaite inhibited the expression of nuclear factor (NF)-κΒ and upregulated that of connexin 43, both of which sensitized cancer cells to Taxol. Moreover, Kanglaite increased many cellular variations caused by Taxol, including tubulin polymerization, caspase-3 cleavage, and upregulated expression of survivin and cyclin B1. These results suggest that Kanglaite pretreatment may increase the effect of Taxol on colorectal cancer.

  7. 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.

  8. Specific β-tubulin isotypes can functionally enhance or diminish epothilone B sensitivity in non-small cell lung cancer cells.

    Directory of Open Access Journals (Sweden)

    Pei Pei Gan

    Full Text Available Epothilones are a new class of microtubule stabilizing agents with promising preclinical and clinical activity. Their cellular target is β-tubulin and factors influencing intrinsic sensitivity to epothilones are not well understood. In this study, the functional significance of specific β-tubulin isotypes in intrinsic sensitivity to epothilone B was investigated using siRNA gene knockdown against βII-, βIII- or βIVb-tubulins in two independent non-small cell lung cancer (NSCLC cell lines, NCI-H460 and Calu-6. Drug-treated clonogenic assays showed that sensitivity to epothilone B was not altered following knockdown of βII-tubulin in both NSCLC cell lines. In contrast, knockdown of βIII-tubulin significantly increased sensitivity to epothilone B. Interestingly, βIVb-tubulin knockdowns were significantly less sensitive to epothilone B, compared to mock- and control siRNA cells. Cell cycle analysis of βIII-tubulin knockdown cells showed a higher percentage of cell death with epothilone B concentrations as low as 0.5 nM. In contrast, βIVb-tubulin knockdown cells displayed a decrease in epothilone B-induced G(2-M cell cycle accumulation compared to control siRNA cells. Importantly, βIII-tubulin knockdowns displayed a significant dose-dependent increase in the percentage of apoptotic cells upon treatment with epothilone B, as detected using caspase 3/7 activity and Annexin-V staining. Higher concentrations of epothilone B were required to induce apoptosis in the βIVb-tubulin knockdowns compared to control siRNA, highlighting a potential mechanism underlying decreased sensitivity to this agent. This study demonstrates that specific β-tubulin isotypes can influence sensitivity to epothilone B and may influence differential sensitivity to this promising new agent.

  9. 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.

  10. The characterization of gefitinib sensitivity and adverse events in patients with non-small cell lung cancer.

    Science.gov (United States)

    Koyama, Nobuyuki; Jinn, Yasuto; Takabe, Kazuhiko; Yoshizawa, Masafumi; Usui, Yutaka; Inase, Naohiko; Miyake, Shuji; Yoshizawa, Yasuyuki; Hagiwara, Koichi; Kanazawa, Minoru

    2006-01-01

    Factors predicting gefitinib sensitivity and adverse events in non-small cell lung cancer (NSCLC) remain controversial. Correlations among clinicopathological characteristics, gefitinib sensitivity and adverse events were studied in 154 patients with NSCLC, whereas epidermal growth factor receptor (EGFR) mutations were analyzed in 44 patients. Female, non-smoker, adenocarcinoma of stage I-II, and gefitinib effectiveness correlated with longer time to progression (TTP) and overall survival (OS), while the rate of interstitial lung disease in patients undergoing thoracic radiotherapy and stomatitis in females or those who never smoked were significantly higher. EGFR mutations were identified in 18 cases, and among 34 gefitinib-treated patients, 16 patients harboring mutations tended to do better, both in terms of TTP and OS. The results of the mutation analysis from surgical and non-surgical specimens were identical. Certain clinicopathological characteristics and EGFR mutations can be either predictive of gefitinib sensitivity or adverse events.

  11. Carnitine sensitizes TRAIL-resistant cancer cells to TRAIL-induced apoptotic cell death through the up-regulation of Bax.

    Science.gov (United States)

    Park, So Jung; Park, Seong Ho; Kim, Joo-Oh; Kim, Jung Ho; Park, So Jung; Hwang, Jung Jin; Jin, Dong-Hoon; Jeong, Seong-Yun; Lee, Seung Jin; Kim, Jin Cheon; Kim, Inki; Cho, Dong-Hyung

    2012-11-09

    Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) is a member of the tumor necrosis factor family with apoptosis-inducing activity. Given that TRAIL selectively induces cell death in various tumors but has little or no toxicity to normal cells, TRAIL agonists have been considered as promising anti-cancer therapeutic agents. However, the resistance of many primary tumors and cancer cells to TRAIL poses a challenge. In our present study, we found that carnitine, a metabolite that transfers long-chain fatty acids into mitochondria for beta-oxidation and modulates protein kinase C activity, sensitizes TRAIL-resistant cancer cells to TRAIL. Combination of carnitine and TRAIL was found to synergistically induce apoptotic cell death through caspase activation, which was blocked by a pan caspase inhibitor, but not by an inhibitor of autophagy or an inhibitor of necrosis. The combination of carnitine and TRAIL reversed the resistance to TRAIL in lung cancer cells, colon carcinoma cells, and breast carcinoma cells. We further demonstrate that carnitine, either alone or in combination with TRAIL, enhances the expression of the pro-apoptotic Bcl-2 family protein, Bcl-2-associated X protein (Bax). The down-regulation of Bax expression by small interfering RNA reduced caspase activation when cells were treated with TRAIL, and experiments with cells from Bax knockout mice confirmed this result. Taken together, our current results suggest that carnitine can reverse the resistance of cancer cells to TRAIL by up-regulating Bax expression. Thus, a combined delivery of carnitine and TRAIL may represent a new therapeutic strategy to treat TRAIL-resistant cancer cells. Copyright © 2012 Elsevier Inc. All rights reserved.

  12. MiR-214 inhibits cell migration, invasion and promotes the drug sensitivity in human cervical cancer by targeting FOXM1.

    Science.gov (United States)

    Wang, Jian-Mei; Ju, Bao-Hui; Pan, Cai-Jun; Gu, Yan; Li, Meng-Qi; Sun, Li; Xu, Yan-Ying; Yin, Li-Rong

    2017-01-01

    MicroRNAs (miRNAs) play key roles in progression of cervical cancer. In the present study, we investigated the role of miR-214 in the process of migration, invasion and drug sensitivity to cisplatin in cervical cancer. We detected the differential expression of miR-214 in 19 cases cervical cancer tissues and normal tissues as well as 4 cervical cancer cells and one normal cervical cells by Real-time PCR. Then, wound healing assay, transwell invasion assay and MTT were used to detect the effects of migration, invasion and sensitivity to cisplatin of cervical cancer when miR-214 was overexpressed. Western blot, immunofluorescence and Flow Cytometry were used to detect the mechanism of migration, invasion and sensitivity to cisplatin. Next, bioinformatics analysis was used to find the target of miR-214. Through the luciferase reporter assay, Real-time PCR and western blot, we confirmed the binding relationship of miR-214 and FOXM1. In cervical cancer tissues, the expression of FOXM1 was detected by western blot and Immunohistochemistry. We also knocked down FOXM1 in cervical cancer cells, wound healing assay, transwell invasion assay and MTT were performed to detect the migration, invasion and sensitivity to cisplatin abilities of FOXM1. Western blot and Flow Cytometry were used to detect the mechanism of migration, invasion and sensitivity to cisplatin by FOXM1. Finally, we performed rescue expriments to confirm the function relationship between miR-214 and FOXM1. 1. Our results showed that miR-214 was frequently downregulated in tumor tissues and cancer cells especially in CIN III and cervical cancer stages. 2. Overexpression of miR-214 significantly inhibited migration and invasion of cervical cancer cells and prompted the sensitivity to cisplatin. 3. FOXM1 was identified as a target of miR-214 and down-regulated by miR-214. 4. Knocking down FOXM1 could inhibited migration and invasion of cervical cancer cells and prompted the sensitivity to cisplatin. 5. FOXM1 was

  13. 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.

  14. 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...

  15. Sinomenine Sensitizes Multidrug-Resistant Colon Cancer Cells (Caco-2) to Doxorubicin by Downregulation of MDR-1 Expression

    Science.gov (United States)

    Liu, Zhen; Duan, Zhi-Jun; Chang, Jiu-Yang; Zhang, Zhi-feng; Chu, Rui; Li, Yu-Ling; Dai, Ke-Hang; Mo, Guang-quan; Chang, Qing-Yong

    2014-01-01

    Chemoresistance in multidrug-resistant (MDR) cells over expressing P-glycoprotein (P-gp) encoded by the MDR1 gene, is a major obstacle to successful chemotherapy for colorectal cancer. Previous studies have indicated that sinomenine can enhance the absorption of various P-gp substrates. In the present study, we investigated the effect of sinomenine on the chemoresistance in colon cancer cells and explored the underlying mechanism. We developed multidrug-resistant Caco-2 (MDR-Caco-2) cells by exposure of Caco-2 cells to increasing concentrations of doxorubicin. We identified overexpression of COX-2 and MDR-1 genes as well as activation of the NF-κB signal pathway in MDR-Caco-2 cells. Importantly, we found that sinomenine enhances the sensitivity of MDR-Caco-2 cells towards doxorubicin by downregulating MDR-1 and COX-2 expression through inhibition of the NF-κB signaling pathway. These findings provide a new potential strategy for the reversal of P-gp-mediated anticancer drug resistance. PMID:24901713

  16. Sensitive Detection of Cell Surface Membrane Proteins in Living Breast Cancer Cells Using Multicolor Fluorescence Microscopy with a Plasmonic Chip.

    Science.gov (United States)

    Tawa, Keiko; Yamamura, Shohei; Sasakawa, Chisato; Shibata, Izumi; Kataoka, Masatoshi

    2016-11-09

    A plasmonic chip was applied to live cancer cell imaging. The epithelial cell adhesion molecule (EpCAM) is a surface marker that can be used to classify breast cancer cell lines into distinct differentiation states. EpCAM and the nuclei of two kinds of living breast cancer cells, MDA-MB231 and MCF-7, were stained with allophycocyanin (APC)-labeled anti-EpCAM antibody and 4',6-diamidino-2-phenylindole (DAPI), respectively, and the cells were scattered on either a plasmonic chip (metal-coated wavelength-scale grating substrate) or a control glass slide. Multicolor fluorescence microscopic imaging allowed fluorescence images of APC-EpCAM to be obtained on the plasmonic chip that were more than 10 times brighter compared with those on the glass slide. In contrast, in the fluorescence images of DAPI-stained nuclei, no difference in brightness was observed between substrates. The fluorescence enhancement of APC-EpCAM in the cell membrane in contact with the plasmonic chip is thought to be due to the excitation of APC molecules localized within the surface plasmon field. Analysis of the cross section of a fluorescence image revealed a distribution of EpCAM at a higher level of fluorescence in the center of the cell image because of contact between the cell membrane and the plasmonic chip. In contrast, fluorescence images of APC-EpCAM taken on a glass slide were so dark that only the outline of the cell was characterized. The plasmonic chip thus constitutes a simple and powerful tool for analyzing the distribution and kinetics of surface marker proteins in cell membranes contacting the chip.

  17. Effect of wound fluid on chemotherapy sensitivity of T24 bladder cancer cells with different enhancer of zeste homolog 2 status.

    Science.gov (United States)

    Bi, Huan; Zhang, Zetian; Guo, Li; Fu, Cheng

    2017-09-08

    The present study investigated the effect of zeste homolog 2 (EZH2) and wound fluid (WF) on chemotherapy sensitivities of T24 bladder cancer cells by using a collagen gel droplet embedded culture-drug sensitivity test (CD-DST). T24 bladder cancer cells with different EZH2 expression levels were co-cultured with postoperative WF from patients with bladder cancer. The CD-DST was performed to detect the sensitivity of tumor cells to gemcitabine and cis-diamminedichloridoplatinum (II) (cisplatin, DDP). The survival rates of the bladder cancer cells were used to determine the drug's chemotherapeutic effect. EZH2 knockdown increased the sensitivity of the cells to gemcitabine and DDP, whereas EZH2 overexpression decreased the chemotherapeutic sensitivity. Except for the situation of EZH2 overexpression, co-culturing with WF induced significantly higher drug resistance in tumor cells. Overexpression of EZH2 and surgery-induced WF promoted the drug resistance of bladder cancer cells to the investigated chemotherapeutic agents, suggesting that more studies are needed to investigate the key mechanisms underlying the EZH2- and WF-induced reduction of susceptibility to chemotherapy drugs.

  18. Glutamine drives glutathione synthesis and contributes to radiation sensitivity of A549 and H460 lung cancer cell lines

    Science.gov (United States)

    Sappington, Daniel R.; Siegel, Eric R.; Hiatt, Gloria; Desai, Abhishek; Penney, Rosalind B.; Jamshidi-Parsian, Azemat; Griffin, Robert J.; Boysen, Gunnar

    2016-01-01

    Background Increased glutamine uptake is known to drive cancer cell proliferation, making tumor cells glutamine-dependent. Glutamine provides additional carbon and nitrogen sources for cell growth. The first step in glutamine utilization is its conversion to glutamate by glutaminase (GLS). Glutamate is a precursor for glutathione synthesis, and we investigated the hypothesis that glutamine drives glutathione synthesis and thereby contributes to cellular defense systems. Methods The importance of glutamine for glutathione synthesis was studied in H460 and A549 lung cancer cell lines using glutamine-free medium and Bis-2-(5-phenyl-acetamido-1,3,4-thiadiazol-2-yl)ethyl sulfide (BPTES) a GLS inhibitor. Metabolic activities were determined by targeted mass spectrometry. Results A significant correlation between glutamine consumption and glutathione excretion was demonstrated in H460 and A549 tumor cells. Culturing in the presence of [13C5]glutamine demonstrated that by 12 hrs >50% of excreted glutathione is derived from glutamine. Culturing in glutamine-free medium or treatment with BPTES, a glutaminase (GLS)-specific inhibitor, reduced cell proliferation and viability, and abolished glutathione excretion. Treatment with glutathione-ester prevented BPTES induced cytotoxicity. Inhibition of GLS markedly radiosensitized the lung tumor cell lines, suggesting an important role of glutamine-derived glutathione in determining radiation sensitivity. Conclusions We demonstrate here for the first time that a significant amount of extracellular glutathione is directly derived from glutamine. This finding adds yet another important function to the already known glutamine dependence of tumor cells and probably tumors as well. General significance Glutamine is essential for synthesis and excretion of glutathione to promote cell growth and viability. PMID:26825773

  19. Overexpression of NAD(P)H:quinone oxidoreductase 1 (NQO1) and genomic gain of the NQO1 locus modulates breast cancer cell sensitivity to quinones.

    Science.gov (United States)

    Glorieux, Christophe; Sandoval, Juan Marcelo; Dejeans, Nicolas; Ameye, Geneviève; Poirel, Hélène Antoine; Verrax, Julien; Calderon, Pedro Buc

    2016-01-15

    Alterations in the expression of antioxidant enzymes are associated with changes in cancer cell sensitivity to chemotherapeutic drugs (menadione and β-lapachone). Mechanisms of acquisition of resistance to pro-oxidant drugs were investigated using a model of oxidative stress-resistant MCF-7 breast cancer cells (Resox cells). FISH experiments were performed in tumor biopsy and breast cancer cells to characterize the pattern of the NQO1 gene. SNP-arrays were conducted to detect chromosomal imbalances. Finally, the importance of NQO1 overexpression in the putative acquisition of either drug resistance or an increased sensitivity to quinones by cancer cells was investigated by immunoblotting and cytotoxicity assays. Genomic gain of the chromosomal band 16q22 was detected in Resox cells compared to parental breast cancer MCF-7 cells and normal human mammary epithelial 250MK cells. This genomic gain was associated with amplification of the NQO1 gene in one tumor biopsy as well as in breast cancer cell lines. Using different breast cell models, we found that NQO1 overexpression was a main determinant for a potential chemotherapy resistance or an increased sensitivity to quinone-bearing compounds. Because NQO1 is frequently modified in tumors at genomic and transcriptomic levels, the impact of NQO1 modulation on breast cancer cell sensitivity places NQO1 as a potential link between cancer redox alterations and resistance to chemotherapy. Thus, the NQO1 gene copy number and NQO1 activity should be considered when quinone-bearing molecules are being utilized as potential drugs against breast tumors. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. The Impact of Thymidylate Synthase and Methylenetetrahydrofolate Reductase Genotypes on Sensitivity to 5-Fluorouracil Treatment in Colorectal Cancer Cells

    Directory of Open Access Journals (Sweden)

    Fakhraddin Naghibalhossaini

    2018-01-01

    Full Text Available 5-fluorouracil (5-FU is one of the major components of many standard regimens for chemotherapy of colorectal cancer (CRC and some other malignancies. Given the known relationship between thymidylate synthase (TS and methylenetetrahydrofolate reductase (MTHFR activity and 5-FU metabolism, this study investigated the impact of selected functional polymorphisms of the TS and MTHFR genes on chemotherapy resistance in 5 human CRC cell lines. HCT116, SW1116, HT29/219, LS180, and Caco-2 CRC cells were cultured as monolayer and their chemosensitivity to 5-FU, oxaliplatin, and irinotecan was determined by MTT assay. Genomic DNA was extracted from the cultured cells, and a 6-bp insertion or deletion (6-bp ins/del polymorphism in 3´-UTR of the TS gene was determined by the PCR-RFLP method. Genotyping of MTHFR 677 C/T and 1298A/C single nucleotide polymorphism (SNP was also performed by MS-PCR and PCR-RFLP, respectively. Caco-2 with the homozygous TS 6-bp ins/ins and MTHFR 677 T/T and 1298 C/C genotype, was the most 5-FU resistant cell line. HCT116 with the homozygous TS 6-bp del/del and MTHFR 1298 A/A and heterozygous MTHFR 677 C/T genotype was the least 5-FU resistant cell. LS180, the second most 5-FU resistant cell line, was heterozygous for all three polymorphic sits. HT29/219 and SW1116 cells with homozygous TS 6-bp ins/ins and heterozygous MTHFR 677 C/T and 1298 A/C genotypes had intermediate 5-FU sensitivity. The results indicate that TS 3´-UTR 6-bp insertion and MTHFR 677T and 1298C alleles increase 5-FU resistance in CRC cells. No relationship was observed between TS and MTHFR genotypes and oxaliplatin or irinotecan sensitivity in these cells.

  1. Mechanisms of drug sensitization to TRA-8, an agonistic death receptor 5 antibody, involve modulation of the intrinsic apoptotic pathway in human breast cancer cells.

    Science.gov (United States)

    Amm, Hope M; Zhou, Tong; Steg, Adam D; Kuo, Huichien; Li, Yufeng; Buchsbaum, Donald J

    2011-04-01

    TRA-8, a monoclonal antibody to death receptor 5 induces apoptosis in various cancer cells; however, the degree of sensitivity varies from highly sensitive to resistant. We have previously shown that resistance to TRA-8 can be reversed by using chemotherapeutic agents, but the mechanism underlying this sensitization was not fully understood. Here, we examined the combination of TRA-8 with doxorubicin or bortezomib in breast cancer cells. In TRA-8-resistant BT-474 and T47D cells, both chemotherapy agents synergistically sensitized cells to TRA-8 cytotoxicity with enhanced activation of apoptosis shown by cleavage of caspases and PARP, reduced Bid, increased proapoptotic Bcl-2 proteins, and increased mitochondrial membrane depolarization. Doxorubicin or bortezomib combined with TRA-8 also reduced Bcl-XL and X-linked inhibitors of apoptosis (XIAP) in treated cells. Furthermore, targeting these proteins with pharmacologic modulators, AT-101, BH3I-2' and AT-406, produced sensitization to TRA-8. TRA-8 combined with AT-101 or BH3I-2', inhibitors of antiapoptotic Bcl-2 proteins, produced synergistic cytotoxicity against ZR-75-1, BT-474, and T47D cells. The IAP-targeting compound, AT-406, was synergistic with TRA-8 in BT-474 cells, and to a lesser extent T47D cells. Activation of the intrinsic apoptotic pathway was a common mechanism associated with sensitization of TRA-8-resistant breast cancer cell lines. Collectively, these studies show that the Bcl-2 and IAP families of proteins are involved in TRA-8 and chemotherapy resistance via their modulation of the intrinsic apoptotic pathway. Targeting these proteins with novel agents sensitized TRA-8-resistant breast cancer cells, suggesting this approach may represent a potent therapeutic strategy in the treatment of breast cancer. ©2011 AACR.

  2. 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.

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

    Directory of Open Access Journals (Sweden)

    Junichi Inaba

    2014-12-01

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

  4. 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.

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

    Science.gov (United States)

    Maca, R D; Panje, W R

    1982-08-01

    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. In additional studies, stimulated lymphocytes of irradiated patients were tested for their sensitivity to the inhibitory effect of PGE2. The mitogen treated lymphocytes from all patients that had just finished irradiation therapy were found to be significantly more sensitive to the inhibition by PGE2 as compared to the normal lymphocyte response. This effect was also found not to be related merely to a low PHA or Con A reactivity of the lymphocytes. In both patient groups there was a striking correlation between the percent augmentation of indomethacin and the percent inhibition of PGE2 in that when the percent augmentation values were low so were percent inhibition values and when the degree of augmentation by indomethacin was elevated so was the inhibition by PGE2. This data suggests that increase sensitivity of stimulated lymphocytes to PGE2 may be responsible, at least in part, for the depressed mitogen response and the significant augmentation of this immune response by indomethacin in about 1/3 of the untreated patients with advanced head and neck carcinoma and in those patients who have just finished irradiation therapy. The results of this study support the hypothesis that perhaps patients receiving irradiation therapy may benefit by

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

    DEFF Research Database (Denmark)

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

    2014-01-01

    Determination of epidermal growth factor receptor (EGFR) mutations has a pivotal impact on treatment of non-small-cell lung cancer (NSCLC). A standardized test has not yet been approved. So far, Sanger DNA sequencing has been widely used. Its rather low sensitivity has led to the development......, 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...... positive (immunohistochemistry positive, RT-PCR negative). One false positive exon21 mutation had staining score 300. The EGFR variantIII antibody showed no correlation to EGFR mutation status determined by RT-PCR or to EGFR immunohistochemistry. High specificity of the mutation-specific antibodies...

  7. Ethanolic extract of Descurainia sophia seeds sensitizes A549 human lung cancer cells to TRAIL cytotoxicity by upregulating death receptors.

    Science.gov (United States)

    Park, Jong-Shik; Lim, Chae Jun; Bang, Ok-Sun; Kim, No Soo

    2016-04-02

    Our previous genome-wide gene expression analysis revealed that tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) death receptors 4 (DR4) and 5 (DR5) are markedly upregulated by the ethanolic extract of D. sohia seeds (EEDS) in A549 TRAIL-refractory cancer cells. In the present study, we investigated whether the EEDS-mediated upregulation of TRAIL death receptors was associated with increased TRAIL-mediated toxicity in A549 cells in vitro. Cell proliferation and viability were determined by an automatic cell counter. Gene silencing was performed by introducing small interfering RNA into cells. Expression changes of cellular proteins were determined by western blot analysis. Apoptotic cell death was monitored by western blot analysis. Analysis of variance followed by the post-hoc Dunnett's test was used to compare the data. EEDS treatment increased both mRNA and protein levels of DR4 and DR5 in the TRAIL refractory A549 cells. Co-treatment of A549 cells with sub-lethal dose of EEDS and recombinant TRAIL increased the apoptotic cell death. Upregulation of DR5 by EEDS was mediated by an endoplasmic reticulum stress-induced transcription factor, CCAAT/enhancer-binding protein homologous protein (CHOP), and knockdown of CHOP expression inhibited EEDS-induced DR5 upregulation and abolished the EEDS-associated increase in TRAIL toxicity in A549 cells. EEDS can sensitize A549 cells to TRAIL cytotoxicity by upregulation of TRAIL death receptors. Our findings suggested that EEDS is a good initial herbal source for the development of an anticancer supplement for anticancer therapeutics associated with TRAIL.

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

    Science.gov (United States)

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

  9. Rapamycin inhibits IGF-1-mediated up-regulation of MDM2 and sensitizes cancer cells to chemotherapy.

    Directory of Open Access Journals (Sweden)

    Wei Du

    Full Text Available The Murine Double Minute 2 (MDM2 protein is a key regulator of cell proliferation and apoptosis that acts primarily by inhibiting the p53 tumor suppressor. Similarly, the PI3-Kinase (PI3K/AKT pathway is critical for growth factor-mediated cell survival. Additionally, it has been reported that AKT can directly phosphorylate and activate MDM2. In this study, we show that IGF-1 up-regulates MDM2 protein levels in a PI3K/AKT-dependent manner. Inhibition of mTOR by rapamycin or expression of a dominant negative eukaryotic initiation factor 4E binding protein 1 (4EBP1 mutant protein, as well as ablation of eukaryotic initiation factor 4E (eIF4E, efficiently abolishes IGF-1-mediated up-regulation of MDM2. In addition, we show that rapamycin effectively inhibits MDM2 expression and sensitizes cancer cells to chemotherapy. Taken together, this study reveals a novel mechanism by which IGF-1 activates MDM2 via the mTOR pathway, and that pharmacologic inhibition of mTOR combined with chemotherapy may be more effective in treatment of a subset of cancers harboring increased MDM2 activation.

  10. Proteomic differential display analysis for TS-1-resistant and -sensitive pancreatic cancer cells using two-dimensional gel electrophoresis and mass spectrometry.

    Science.gov (United States)

    Yoshida, Kanako; Kuramitsu, Yasuhiro; Murakami, Kohei; Ryozawa, Shomei; Taba, Kumiko; Kaino, Seiji; Zhang, Xiulian; Sakaida, Isao; Nakamura, Kazuyuki

    2011-06-01

    TS-1 is an oral anticancer agent containing two biochemical modulators for 5-fluorouracil (5-FU) and tegafur (FT), a metabolically activated prodrug of 5-FU. TS-1 has been recognized as an effective anticancer drug using standard therapies for patients with advanced pancreatic cancer along with gemcitabine. However, a high level of inherent and acquired tumor resistance to TS-1 induces difficulty in the treatment. To identify proteins linked to the TS-1-resistance of pancreatic cancer, we profiled protein expression levels in samples of TS-1-resistant and -sensitive pancreatic cancer cell lines by using two-dimensional gel electrophoresis (2-DE) and liquid chromatography-tandem mass spectrometry (LC-MS/MS). The cytotoxicity of a 5-FU/5-chloro-2,4-dihydroxypyridine (CDHP) combination towards pancreatic cancer cell lines was evaluated by MTS assay. Panc-1, BxPC-3, MiaPaCa-2 and PK59 showed high sensitivity to the 5-FU/CDHP combination (TS-1-sensitive), whereas PK45p and KLM-1 were much less sensitive (TS-1-resistant). Proteomic analysis showed that eleven spots, including T-complex protein 1 subunit beta, ribonuclease inhibitor, elongation factor 1-delta, peroxiredoxin-2 and superoxide dismutase (Cu-Zn), appeared to be down-regulated, and 29 spots, including hypoxia up-regulated protein 1, lamin-A/C, endoplasmin, fascin and annexin A1, appeared to be up-regulated in TS-1-resistant cells compared with -sensitive cells. These results suggest that the identified proteins showing different expression between TS-1-sensitive and -resistant pancreatic cancer cells possibly relate to TS-1-sensitivity. These findings could be useful to overcome the TS-1-resistance of pancreatic cancer cells.

  11. SIRT2 Deacetylates and Inhibits the Peroxidase Activity of Peroxiredoxin-1 to Sensitize Breast Cancer Cells to Oxidant Stress-Inducing Agents.

    Science.gov (United States)

    Fiskus, Warren; Coothankandaswamy, Veena; Chen, Jianguang; Ma, Hongwei; Ha, Kyungsoo; Saenz, Dyana T; Krieger, Stephanie S; Mill, Christopher P; Sun, Baohua; Huang, Peng; Mumm, Jeffrey S; Melnick, Ari M; Bhalla, Kapil N

    2016-09-15

    SIRT2 is a protein deacetylase with tumor suppressor activity in breast and liver tumors where it is mutated; however, the critical substrates mediating its antitumor activity are not fully defined. Here we demonstrate that SIRT2 binds, deacetylates, and inhibits the peroxidase activity of the antioxidant protein peroxiredoxin (Prdx-1) in breast cancer cells. Ectopic overexpression of SIRT2, but not its catalytically dead mutant, increased intracellular levels of reactive oxygen species (ROS) induced by hydrogen peroxide, which led to increased levels of an overoxidized and multimeric form of Prdx-1 with activity as a molecular chaperone. Elevated levels of SIRT2 sensitized breast cancer cells to intracellular DNA damage and cell death induced by oxidative stress, as associated with increased levels of nuclear FOXO3A and the proapoptotic BIM protein. In addition, elevated levels of SIRT2 sensitized breast cancer cells to arsenic trioxide, an approved therapeutic agent, along with other intracellular ROS-inducing agents. Conversely, antisense RNA-mediated attenuation of SIRT2 reversed ROS-induced toxicity as demonstrated in a zebrafish embryo model system. Collectively, our findings suggest that the tumor suppressor activity of SIRT2 requires its ability to restrict the antioxidant activity of Prdx-1, thereby sensitizing breast cancer cells to ROS-induced DNA damage and cell cytotoxicity. Cancer Res; 76(18); 5467-78. ©2016 AACR. ©2016 American Association for Cancer Research.

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

    Science.gov (United States)

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

    2016-12-01

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

  13. 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.

  14. The kinase RSK2 modulates the sensitivity of ovarian cancer cells to cisplatin

    NARCIS (Netherlands)

    van Jaarsveld, Marijn T. M.; Blijdorp, Iris C. J.; Boersma, Antonius W. M.; Pothof, Joris; Mathijssen, Ron H. J.; Verweij, Jaap; Wiemer, Erik A. C.

    2013-01-01

    Platinum-based chemotherapy (e.g. cisplatin, carboplatin) is standard of care for many types of cancer including ovarian cancer, however, the efficacy of treatment is hampered by the development of therapy resistance. The mechanisms behind platinum resistance are not completely understood. Here, we

  15. The cranberry flavonoids PAC DP-9 and quercetin aglycone induce cytotoxicity and cell cycle arrest and increase cisplatin sensitivity in ovarian cancer cells.

    Science.gov (United States)

    Wang, Yifei; Han, Alex; Chen, Eva; Singh, Rakesh K; Chichester, Clinton O; Moore, Richard G; Singh, Ajay P; Vorsa, Nicholi

    2015-05-01

    Cranberry flavonoids (flavonols and flavan-3-ols), in addition to their antioxidant properties, have been shown to possess potential in vitro activity against several cancers. However, the difficulty of isolating cranberry compounds has largely limited anticancer research to crude fractions without well-defined compound composition. In this study, individual cranberry flavonoids were isolated to the highest purity achieved so far using gravity and high performance column chromatography and LC-MS characterization. MTS assay indicated differential cell viability reduction of SKOV-3 and OVCAR-8 ovarian cancer cells treated with individual cranberry flavonoids. Treatment with quercetin aglycone and PAC DP-9, which exhibited the strongest activity, induced apoptosis, led to caspase-3 activation and PARP deactivation, and increased sensitivity to cisplatin. Furthermore, immunofluorescence microscopy and western blot study revealed reduced expression and activation of epidermal growth factor receptor (EGFR) in PAC DP-9 treated SKOV-3 cells. In addition, quercetin aglycone and PAC DP-9 deactivated MAPK-ERK pathway, induced downregulation of cyclin D1, DNA-PK, phospho-histone H3 and upregulation of p21, and arrested cell cycle progression. Overall, this study demonstrates promising in vitro cytotoxic and anti-proliferative properties of two newly characterized cranberry flavonoids, quercetin aglycone and PAC DP-9, against ovarian cancer cells.

  16. IMPAIRED SHP2-MEDIATED ERK ACTIVATION CONTRIBUTES TO GEFITINIB SENSITIVITY OF LUNG CANCER CELLS WITH EGFR-ACTIVATING MUTATIONS

    Science.gov (United States)

    Lazzara, Matthew J.; Lane, Keara; Chan, Richard; Jasper, Paul J.; Yaffe, Michael B.; Sorger, Peter K.; Jacks, Tyler; Neel, Benjamin G.; Lauffenburger, Douglas A.

    2010-01-01

    Most non-small cell lung cancers (NSCLC) display elevated expression of epidermal growth factor receptor (EGFR), but response to EGFR kinase inhibitors is predominantly limited to NSCLC harboring EGFR-activating mutations. These mutations are associated with increased activity of survival pathways including PI3K/AKT and STAT3/5. We report that EGFR-activating mutations also surprisingly lead to decreased ability to activate ERK compared to wild-type EGFR. In NSCLC cells and mouse embryonic fibroblasts expressing mutant EGFR, this effect on ERK correlates with decreased EGFR internalization and reduced phosphorylation of SHP2, a tyrosine phosphatase required for the full activation of ERK. We further demonstrate that ERK activation levels impact cellular response to gefitinib. NSCLC cells with EGFR mutation display reduced gefitinib sensitivity when ERK activation is augmented by expression of constitutively active mutants of MEK. Conversely, in an NSCLC cell line expressing wild-type EGFR, gefitinib treatment along with or following MEK inhibition increases death response compared to treatment with gefitinib alone. Our results demonstrate that EGFR-activating mutations may promote some survival pathways but simultaneously impair others. This multivariate alteration of the network governing cellular response to gefitinib, which we term “oncogene imbalance”, portends a potentially broader ability to treat gefitinib-resistant NSCLC. PMID:20406974

  17. The impact of insulin on chemotherapeutic sensitivity to 5-fluorouracil in gastric cancer cell lines SGC7901, MKN45 and MKN28.

    Science.gov (United States)

    Wei, Zhao; Liang, Li; Junsong, Liu; Rui, Chen; Shuai, Chang; Guanglin, Qiu; Shicai, He; Zexing, Wang; Jin, Wang; Xiangming, Che; Shufeng, Wang

    2015-06-18

    The role of insulin in the pathogenesis of cancer has been increasingly emphasized because of the high incidence of obesity and metabolic syndrome and their correlated complication including cancer. This study aimed to explore the impact of insulin on chemoresistance to 5-fluorouracil in gastric cancer and the possible mechanisms. Tissue samples of gastric cancer and adjacent normal gastric mucosa from patients with or without obesity were performed immunohistochemical staining for P-glycoprotein. The follow-up was done after the surgical treatment. The effect of insulin on chemotherapeutic sensitivity of the three gastric cancer cell lines to 5-fluorouracil was evaluated by pre-incubation with insulin before administration of 5-fluorouracil. The expression of P-glycoprotein was determined by Western blotting. P-glycoprotein were overexpressed in tissues from patients who suffered gastric cancer and were higher in those simultaneously suffered gastric cancer and obesity. Addition of 1 μM insulin remarkably promoted the proliferation of SGC7901, MKN45 and MKN28 cells and decreased the cytotoxicity of 5-fluorouracil. In addition, the expression of P-glycoprotein was upregulated in SGC7901, MKN45 and MKN28 cells. Insulin improved the proliferation of gastric cancer cell lines and contributed to chemoresistance of gastric cancer cells to 5-fluorouracil which is likely to involve upregulation of P-glycoprotein.

  18. 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.

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

    Science.gov (United States)

    Bondgaard, Anna-Louise; Høgdall, Estrid; Mellemgaard, Anders; Skov, Birgit G

    2014-12-01

    Determination of epidermal growth factor receptor (EGFR) mutations has a pivotal impact on treatment of non-small-cell lung cancer (NSCLC). A standardized test has not yet been approved. So far, Sanger DNA sequencing has been widely used. Its rather low sensitivity has led to the development 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 PCR kit, Qiagen, UK; reference method). For immunohistochemistry, antibodies against exon19 deletions (clone 6B6), exon21 mutations (clone 43B2) from Cell Signaling Technology (Boston, USA) and EGFR variantIII (clone 218C9) from Dako (Copenhagen, DK) were applied. Protein expression was evaluated, 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=94.4-99.4%). Sensitivity of exon19 antibody was 63.2% (95% confidence interval=38.4-83.7%) and of exon21 antibody was 80.0% (95% confidence interval=44.4-97.5%). Seven exon19 and four exon21 mutations were false negatives (immunohistochemistry negative, RT-PCR positive). Two exon19 and three exon21 mutations were false positive (immunohistochemistry positive, RT-PCR negative). One false positive exon21 mutation had staining score 300. The EGFR variantIII antibody showed no correlation to EGFR mutation status determined by RT-PCR or to EGFR immunohistochemistry. High specificity of the mutation-specific antibodies 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

  20. Bioinformatic analyses identifies novel protein-coding pharmacogenomic markers associated with paclitaxel sensitivity in NCI60 cancer cell lines.

    Science.gov (United States)

    Eng, Lawson; Ibrahim-zada, Irada; Jarjanazi, Hamdi; Savas, Sevtap; Meschian, Mehran; Pritchard, Kathleen I; Ozcelik, Hilmi

    2011-02-11

    Paclitaxel is a microtubule-stabilizing drug that has been commonly used in treating cancer. Due to genetic heterogeneity within patient populations, therapeutic response rates often vary. Here we used the NCI60 panel to identify SNPs associated with paclitaxel sensitivity. Using the panel's GI50 response data available from Developmental Therapeutics Program, cell lines were categorized as either sensitive or resistant. PLINK software was used to perform a genome-wide association analysis of the cellular response to paclitaxel with the panel's SNP-genotype data on the Affymetrix 125 k SNP array. FastSNP software helped predict each SNP's potential impact on their gene product. mRNA expression differences between sensitive and resistant cell lines was examined using data from BioGPS. Using Haploview software, we investigated for haplotypes that were more strongly associated with the cellular response to paclitaxel. Ingenuity Pathway Analysis software helped us understand how our identified genes may alter the cellular response to paclitaxel. 43 SNPs were found significantly associated (FDRlines. Haplotypes found in GRIK1, SGCD, ROBO1, LPHN2, and PTPRD were more strongly associated with response than their individual SNPs. Our study has taken advantage of available genotypic data and its integration with drug response data obtained from the NCI60 panel. We identified 10 SNPs located within protein-coding genes that were not previously shown to be associated with paclitaxel response. As only five genes showed differential mRNA expression, the remainder would not have been detected solely based on expression data. The identified haplotypes highlight the role of utilizing SNP combinations within genomic loci of interest to improve the risk determination associated with drug response. These genetic variants represent promising biomarkers for predicting paclitaxel response and may play a significant role in the cellular response to paclitaxel.

  1. 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.

  2. 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.

  3. 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.

  4. NADPH alkenal/one oxidoreductase activity determines sensitivity of cancer cells to the chemotherapeutic alkylating agent irofulven.

    Science.gov (United States)

    Dick, Ryan A; Yu, Xiang; Kensler, Thomas W

    2004-02-15

    Illudins S and M are extremely cytotoxic products of the fungus Omphalotus illudens. They were evaluated as possible anticancer chemotherapeutic agents but displayed unfavorable therapeutic indices. Irofulven (6-hydroxymethylacylfulvene), a less toxic, synthetic derivative of illudin S, has proven very effective in many preclinical and clinical studies. It has been postulated that metabolism via hydrogenation of the 8,9-double bonds of these molecules would unmask the electrophilic, and thus, the toxic nature of their cyclopropyl moieties. Illudins S and M were found to be rapidly metabolized by NADPH-dependent alkenal/one oxidoreductase (AOR) with maximal rates of 115.9 and 44.1 micromol x min(-1) mg(-1), and K(m)s of 308 and 109 microM, respectively. Irofulven was reduced at a much slower rate: V(max) 275 nmol min(-1) mg(-1) and K(m) 145 microM. Human 293 cells transfected with an AOR overexpression vector were 100-fold more sensitive than control cells to irofulven, but displayed little differential sensitivity to illudin M. Addition of glutathione to the alpha,beta-unsaturated ketone moiety of illudin M, but not irofulven, occurred readily at physiological concentrations. Electrophilic intermediates of irofulven and illudin M that were activated by AOR were trapped with glutathione and identified by high performance liquid chromatography with tandem mass spectrometry. Samples of the 60 human tumor cell line panel used by the National Cancer Institute to evaluate potential chemotherapeutic compounds were assayed for AOR activity, which correlated positively with previously determined growth inhibitory measures for irofulven, but not illudin M or S. Collectively, these data indicate that bioactivation of irofulven by AOR plays a predominant role in its chemotherapeutic activity.

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

    Science.gov (United States)

    2013-08-01

    Studies in Melbourne, Australia AWARDS • Department of Defense Breast Cancer Research Program Predoctoral Fellowship 2011-present • UAB...Assisted terminally ill patients at Clinico Moncloa, Madrid Spain 2005 • American Multicultural Student Leadership Conference, Madison, WI 2004...Melbourne, Australia 2003 WORK EXPERIENCE Hyde Park Dermatology- Medical Assistant/Insurance Coder 2007 Latin Solutions Marketing- Brand

  6. The radio-sensitizing effect of xanthohumol is mediated by STAT3 and EGFR suppression in doxorubicin-resistant MCF-7 human breast cancer cells.

    Science.gov (United States)

    Kang, Youra; Park, Min A; Heo, Se-Woong; Park, Su-Young; Kang, Keon Wook; Park, Pil-Hoon; Kim, Jung-Ae

    2013-03-01

    Chemotherapeutic drug resistance remains a clinical obstacle in cancer management. Drug-resistant cancer cells usually exhibit cross-resistance to ionizing radiation, which has devastating consequences for patients. With a better understanding of the molecular mechanisms, it will be possible to develop strategies to overcome this cross-resistance and to increase therapeutic sensitivity. Natural and synthetic flavonoid compounds including xanthohumol, the principal flavonoid in hops, were investigated for its radio-sensitizing activity on human breast cancer MCF-7 and adriamycin-resistant MCF-7 (MCF-7/ADR) cells. Chemo-sensitizing or radio-sensitizing effect was analyzed by tetrazolium-based colorimetric assay and flow cytometry. Western blot analysis, confocal microscopy, gene silencing with siRNA transfection and luciferase reporter gene assay were performed to examine signaling molecule activation. Among the tested flavonoid compounds, pretreatment of the cells with xanthohumol significantly sensitized MCF-7/ADR cells to the radiation treatment by inducing apoptosis. In MCF-7/ADR cells, treatment with xanthohumol alone or with gamma-rays significantly decreased levels of anti-apoptotic proteins. Multi-drug resistance 1 (MDR1), epidermal growth factor receptor (EGFR) and signal transducer and activator of transcription 3 (STAT3) expression levels in MCF-7/ADR cells were suppressed by xanthohumol treatment. In addition, xanthohumol treatment increased death receptor (DR)-4 and DR5 expression. The xanthohumol-induced changes of these resistance-related molecules in MCF-7/ADR cells were synergistically increased by gamma-ray treatment. Xanthohumol restored sensitivity of MCF-7/ADR cells to doxorubicin and radiation therapies. Our results suggest that xanthohumol may be a potent chemo- and radio-sensitizer, and its actions are mediated through STAT3 and EGFR inhibition.

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

    DEFF Research Database (Denmark)

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

    2012-01-01

    Background and aims: A positive relationship between topoisomerase-1 (TOP1) protein and sensitivity towards the TOP1 inhibitor irinotecan has been reported in patients with metastatic colorectal cancer (mCRC). The aim of this study was to analyse TOP1 gene copy number variation in tumor tissue from...... and in vitro sensitivity to SN-38 (the active metabolite of irinotecan) and oxaliplatin were tested for 10 CRC cell lines. Results: The crude TOP1 copy numbers as well as the TOP1/CEN-20 mean ratio +/- 3 STD were determined in non-affected mucosa and in the malignant epithelium of the tumors. In the malignant...... epithelium 84% of the samples demonstrated an increased TOP1 gene copy number and 66% had an increased TOP1/CEN-20 ratio compared to the non-affected mucosa. Sixteen (32%) of the tumors had a ratio = 1.5 and 9 of these had a ratio of = 2.0. A positive association was observed between the TOP1 gene copy...

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-01-01

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

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

    DEFF Research Database (Denmark)

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

    2009-01-01

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

  10. 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.

  11. miR-34a sensitizes lung cancer cells to cisplatin via p53/miR-34a/MYCN axis.

    Science.gov (United States)

    Song, Changshan; Lu, Pingfang; Sun, Guoqiang; Yang, Lin; Wang, Zhigang; Wang, Zheng

    2017-01-01

    Cisplatin is the most potent and widespread used chemotherapy drug for lung cancer treatment. However, a large proportion of NSCLC patients were insensitive to chemotherapy. This study explored the role of miR-34a in regulating sensitivity of NSCLC cells to cisplatin and its downstream targets. The quantitative PCR result showed that miR-34a expression was upregulated in cisplatin sensitive NSCLC patients compared cisplatin insensitive NSCLC controls. By applying loss-and-gain function analysis, we demonstrated that miR-34a directly targeted to MYCN to sensitize NSCLC cells to cisplatin. In addition, p53 was found to monitor the expression of miR-34a in NSCLC cells after cisplatin treatment. Therefore, the sensitivity of cisplatin in NSCLC cells was modulated via p53/miR-34a/MYCN axis. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. BIM-mediated AKT phosphorylation is a key modulator of arsenic trioxide-induced apoptosis in cisplatin-sensitive and -resistant ovarian cancer cells.

    Directory of Open Access Journals (Sweden)

    Zhu Yuan

    Full Text Available Chemo-resistance to cisplatin-centered cancer therapy is a major obstacle to the effective treatment of human ovarian cancer. Previous reports indicated that arsenic trioxide (ATO induces cell apoptosis in both drug-sensitive and -resistant ovarian cancer cells.In this study, we determined the molecular mechanism of ATO-induced apoptosis in ovarian cancer cells. Our data demonstrated that ATO induced cell apoptosis by decreasing levels of phosphorylated AKT (p-AKT and activating caspase-3 and caspase-9. Importantly, BIM played a critical role in ATO-induced apoptosis. The inhibition of BIM expression prevented AKT dephosphorylation and inhibited caspase-3 activation during cell apoptosis. However, surprisingly, gene silencing of AKT or FOXO3A had little effect on BIM expression and phosphorylation. Moreover, the activation of caspase-3 by ATO treatment improved AKT dephosphorylation, not only by cleaving the regulatory A subunit of protein phosphatase 2A (PP2A, but also by increasing its activation. Furthermore, our data indicated that the c-Jun N-terminal kinases (JNK pathway is involved in the regulation of BIM expression.We demonstrated the roles of BIM in ATO-induced apoptosis and the molecular mechanisms of BIM expression regulated by ATO during ovarian cancer cell apoptosis. Our findings suggest that BIM plays an important role in regulating p-AKT by activating caspase-3 and that BIM mediates the level of AKT phosphorylation to determine the threshold for overcoming cisplatin resistance in ovarian cancer cells.

  13. Silicon photonic crystal microarrays for high throughput label-free detection of lung cancer cell line lysates with sensitivity and specificity

    Science.gov (United States)

    Chakravarty, Swapnajit; Lai, Wei-Cheng; Zou, Yi; Gemmill, Robert M.; Chen, Ray T.

    2013-03-01

    Detection of biomolecules on microarrays based on label-free on-chip optical biosensors is very attractive since this format avoids complex chemistries caused by steric hindrance of labels. Application areas include the detection of cancers and allergens, and food-borne pathogens to name a few. We have demonstrated photonic crystal microcavity biosensors with high sensitivity down to 1pM concentrations (67pg/ml). High sensitivities were achieved by slow light engineering which reduced the radiation loss and increased the stored energy in the photonic crystal microcavity resonance mode. Resonances with high quality factor Q~26,760 in liquid ambient, coupled with larger optical mode volumes allowed enhanced interaction with the analyte biomolecules which resulted in sensitivities down to 10 cells per micro-liter to lung cancer cell lysates. The specificity of detection was ensured by multiplexed detections from multiple photonic crystal microcavities arrayed on the arms of a multimode interference power splitter. Specific binding interactions and control experiments were performed simultaneously at the same instant of time with the same 60 microliter sample volume. Specificity is further ensured by sandwich assay methods in the multiplexed experiment. Sandwich assay based amplification increased the sensitivity further resulting in the detection of lung cancer cell lysates down to concentrations of 2 cells per micro-liter. The miniaturization enabled by photonic crystal biosensors coupled with waveguide interconnected layout thus offers the potential of high throughput proteomics with high sensitivity and specificity.

  14. Suppression of PC-1/PrLZ sensitizes prostate cancer cells to ionizing radiation by attenuating DNA damage repair and inducing autophagic cell death

    OpenAIRE

    Shang, Zeng-Fu; Wei, Qiang; Yu, Lan; Huang, Fang; Xiao, Bei-Bei; Wang, Hongtao; Song, Man; Wang, Li; Zhou, Jianguang; Wang, Jian; Li, Shanhu

    2016-01-01

    Radiotherapy is promising and effective for treating prostate cancer but the addition of a tumor cell radiosensitizer would improve therapeutic outcomes. PC-1/PrLZ, a TPD52 protein family member is frequently upregulated in advanced prostate cancer cells and may be a biomarker of aggressive prostate cancer. Therefore, we investigated the potential role of PC-1/PrLZ for increasing radioresistance in human prostate cancer cell lines. Growth curves and survival assays after g-ray irradiation con...

  15. Specific isolation of disseminated cancer cells: a new method permitting sensitive detection of target molecules of diagnostic and therapeutic value.

    Science.gov (United States)

    Tveito, Siri; Maelandsmo, Gunhild M; Hoifodt, Hanne K; Rasmussen, Heidi; Fodstad, Oystein

    2007-01-01

    Molecular studies of rare cells, such as circulating cancer cells, require efficient pre-enrichment steps to obtain a pure population of target cells for further characterization. We have developed a two-step approach, starting with immunomagnetic enrichment, followed by specific isolation of individual, easily identifiable bead-rosetted target cells using a new semi-automated CellPick system. With this procedure, 1-50 live target cells can now be isolated. As a model system, we spiked a small number of tumor cells into millions of normal mononuclear cells (MNCs). Efficient isolation of pure target cells was obtained by use of the CellPick system, and the nature of isolated, bead-rosetted cells was verified by use of FISH. Single breast cancer cells were picked directly into an RNA preserving lysis buffer, reverse transcribed, and PCR amplified with two cDNA specific primer sets. With the isolated cells we consistently obtained both ubiquitously expressed and tumor cell specific PCR products. We also performed a successful mutation analysis of single cells using PCR and cycling temperature capillary electrophoresis (CTCE). This may have significant clinical implications in cancer and in other diseases, e.g. in characterizing micrometastatic cancer cells in blood and lymph nodes to help identifying patients who most likely will respond to therapies like tyrosine kinase inhibitors and compounds targeting specific mutations. By use of the CellPick system it is possible to specifically isolate bead-rosetted or otherwise labelled target cells from a heterogeneous cell population for further molecular characterization.

  16. 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.

  17. 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.

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

    Science.gov (United States)

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

    2015-03-30

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

  19. 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.

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

    Directory of Open Access Journals (Sweden)

    Sharad Kholia

    2015-06-01

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

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

    Science.gov (United States)

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

    2014-12-01

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

  2. Backstabbing P-gp: Side-Chain Cleaved Ecdysteroid 2,3-Dioxolanes Hyper-Sensitize MDR Cancer Cells to Doxorubicin without Efflux Inhibition.

    Science.gov (United States)

    Hunyadi, Attila; Csábi, József; Martins, Ana; Molnár, Joseph; Balázs, Attila; Tóth, Gábor

    2017-01-25

    P-glycoprotein (P-gp, ABCB1) over-expression, causing a multi-drug resistant (MDR) phenotype, is a major problem in cancer chemotherapy that urgently requires novel approaches. Our previous studies showed certain ecdysteroid derivatives as promising chemo-sensitizers against MDR and non-MDR cancer cell lines while also exerting mild to moderate inhibition of P-gp function. Here we report the preparation of a set of substituted 2,3-dioxolane derivatives of poststerone, a known in vivo metabolite of 20-hydroxyecdysone (20E). In contrast with previously studied ecdysteroid dioxolanes, the majority of the new compounds did not inhibit the efflux function of P-gp. Nevertheless, a strong, dose dependent sensitization to doxorubicin was observed on a P-gp transfected cancer cell line and on its susceptible counterpart. We also observed that the MDR cell line was more sensitive to the compounds' effect than the non-MDR. Our results showed for the first time that the chemo-sensitizing activity of ecdysteroids can be fully independent of functional efflux pump inhibition, and suggest these compounds as favorable leads against MDR cancer.

  3. 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.

  4. 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.

  5. Size-Based Enrichment of Exfoliated Tumor Cells in Urine Increases the Sensitivity for DNA-Based Detection of Bladder Cancer

    DEFF Research Database (Denmark)

    Andersson, Elin; Steven, Kenneth; Guldberg, Per

    2014-01-01

    fractions and small numbers of tumor cells exfoliated into the urine from low-grade tumors. The purpose of this study was to improve the sensitivity for non-invasive detection of bladder cancer by size-based capture and enrichment of tumor cells in urine. In a split-sample set-up, urine from a consecutive......Bladder cancer is diagnosed by cystoscopy, a costly and invasive procedure that is associated with patient discomfort. Analysis of tumor-specific markers in DNA from sediments of voided urine has the potential for non-invasive detection of bladder cancer; however, the sensitivity is limited by low...... series of patients with primary or recurrent bladder tumors (N = 189) was processed by microfiltration using a membrane filter with a defined pore-size, and sedimentation by centrifugation, respectively. DNA from the samples was analyzed for seven bladder tumor-associated methylation markers using Methy...

  6. Ferrocene-cinchona hybrids with triazolyl-chalcone linkers act as pro-oxidants and sensitize human cancer cell lines to paclitaxel.

    Science.gov (United States)

    Podolski-Renić, Ana; Bősze, Szilvia; Dinić, Jelena; Kocsis, László; Hudecz, Ferenc; Csámpai, Antal; Pešić, Milica

    2017-08-16

    Recently, we demonstrated that ferrocene-containing compounds with a cinchona moiety displayed marked anticancer activity. Here we report on the effects of the most promising isomers encompassing quinine- (compounds 4 and 5) and quinidine-epimers (compounds 6 and 7) - synthesized using improved methods providing controlled diastereoselectivity - in three different human multidrug resistant (MDR) cancer cell lines and their sensitive counterparts (non-small cell lung carcinoma NCI-H460/R/NCI-H460, colorectal carcinoma DLD1-TxR/DLD1 and glioblastoma U87-TxR/U87). We observed that the presence of the MDR phenotype did not diminish the activity of the compounds suggesting that ferrocene quinine- and quinidine-epimers are not substrates for P-glycoprotein, which has been indicated as a major mechanism of MDR in the cell lines used. Considering that metal-based anticancer agents mainly act by increasing ROS production, we investigated the potential of ferrocene-quinidine epimers to generate ROS. We found that 6 and 7 more readily increased ROS production and induced mitochondrial damage in MDR cancer cells. According to cell death analysis, 6 and 7 were more active against MDR cancer cells showing collateral sensitivity. In addition, our data suggest that these compounds could act as inhibitors of autophagy. Importantly, simultaneous treatments of 6 and 7 with paclitaxel (PTX) increased the sensitivity of MDR cancer cells to PTX. In conclusion, the ferrocene-quinidine epimers, besides being selective towards MDR cancer cells, could also possess potential to overcome PTX resistance.

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

    Science.gov (United States)

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

    2017-12-28

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

  8. DMAPT inhibits NF-κB activity and increases sensitivity of prostate cancer cells to X-rays in vitro and in tumor xenografts in vivo.

    Science.gov (United States)

    Mendonca, Marc S; Turchan, William T; Alpuche, Melanie E; Watson, Christopher N; Estabrook, Neil C; Chin-Sinex, Helen; Shapiro, Jeremy B; Imasuen-Williams, Imade E; Rangel, Gabriel; Gilley, David P; Huda, Nazmul; Crooks, Peter A; Shapiro, Ronald H

    2017-11-01

    Constitutive activation of the pro-survival transcription factor NF-κB has been associated with resistance to both chemotherapy and radiation therapy in many human cancers, including prostate cancer. Our lab and others have demonstrated that the natural product parthenolide can inhibit NF-κB activity and sensitize PC-3 prostate cancers cells to X-rays in vitro; however, parthenolide has poor bioavailability in vivo and therefore has little clinical utility in this regard. We show here that treatment of PC-3 and DU145 human prostate cancer cells with dimethylaminoparthenolide (DMAPT), a parthenolide derivative with increased bioavailability, inhibits constitutive and radiation-induced NF-κB binding activity and slows prostate cancer cell growth. We also show that DMAPT increases single and fractionated X-ray-induced killing of prostate cancer cells through inhibition of DNA double strand break repair and also that DMAPT-induced radiosensitization is, at least partially, dependent upon the alteration of intracellular thiol reduction-oxidation chemistry. Finally, we demonstrate that the treatment of PC-3 prostate tumor xenografts with oral DMAPT in addition to radiation therapy significantly decreases tumor growth and results in significantly smaller tumor volumes compared to xenografts treated with either DMAPT or radiation therapy alone, suggesting that DMAPT might have a potential clinical role as a radiosensitizing agent in the treatment of prostate cancer. Copyright © 2017 Elsevier Inc. All rights reserved.

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

    Directory of Open Access Journals (Sweden)

    Hui-Wen Chiu

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

  10. Lidocaine Sensitizes the Cytotoxicity of Cisplatin in Breast Cancer Cells via Up-Regulation of RARβ2 and RASSF1A Demethylation

    Science.gov (United States)

    Li, Kehan; Yang, Jianxue; Han, Xuechang

    2014-01-01

    It has been reported that lidocaine is toxic to various types of cells. And a recent study has confirmed that lidocaine exerts a demethylation effect and regulates the proliferation of human breast cancer cell lines. To recognize a potential anti-tumor effect of lidocaine, we evaluated the DNA demethylation by lidocaine in human breast cancer lines, MCF-7 and MDA-MB-231 cells, and determined the influence of demethylation on the toxicity to these cells of cisplatin, which is a commonly utilized anti-tumor agent for breast cancer. Results demonstrated that lidocaine promoted a significant global genomic demethylation, and particularly in the promoters of tumor suppressive genes (TSGs), RARβ2 and RASSF1A. Further, the lidocaine treatment increased cisplatin-induced apoptosis and enhanced cisplatin-induced cytotoxicity. The combined treatment with both lidocaine and cisplatin promoted a significantly higher level of MCF-7 cell apoptosis than singular lidocaine or cisplatin treatment. Moreover, the abrogation of RARβ2 or RASSF1A expression inhibited such apoptosis. In conclusion, the present study confirms the demethylation effect of lidocaine in breast cancer cells, and found that the demethylation of RARβ2 and RASSF1A sensitized the cytotoxicity of cisplatin in breast cancer cells. PMID:25526566

  11. Bioinformatic analyses identifies novel protein-coding pharmacogenomic markers associated with paclitaxel sensitivity in NCI60 cancer cell lines

    Directory of Open Access Journals (Sweden)

    Jarjanazi Hamdi

    2011-02-01

    Full Text Available Abstract Background Paclitaxel is a microtubule-stabilizing drug that has been commonly used in treating cancer. Due to genetic heterogeneity within patient populations, therapeutic response rates often vary. Here we used the NCI60 panel to identify SNPs associated with paclitaxel sensitivity. Using the panel's GI50 response data available from Developmental Therapeutics Program, cell lines were categorized as either sensitive or resistant. PLINK software was used to perform a genome-wide association analysis of the cellular response to paclitaxel with the panel's SNP-genotype data on the Affymetrix 125 k SNP array. FastSNP software helped predict each SNP's potential impact on their gene product. mRNA expression differences between sensitive and resistant cell lines was examined using data from BioGPS. Using Haploview software, we investigated for haplotypes that were more strongly associated with the cellular response to paclitaxel. Ingenuity Pathway Analysis software helped us understand how our identified genes may alter the cellular response to paclitaxel. Results 43 SNPs were found significantly associated (FDR CFTR, ROBO1, PTPRD, BTBD12, DCT, SNTG1, SGCD, LPHN2, GRIK1, ZNF607. SNPs in GRIK1, DCT, SGCD and CFTR were predicted to be intronic enhancers, altering gene expression, while SNPs in ZNF607 and BTBD12 cause conservative missense mutations. mRNA expression analysis supported these findings as GRIK1, DCT, SNTG1, SGCD and CFTR showed significantly (p GRIK1, SGCD, ROBO1, LPHN2, and PTPRD were more strongly associated with response than their individual SNPs. Conclusions Our study has taken advantage of available genotypic data and its integration with drug response data obtained from the NCI60 panel. We identified 10 SNPs located within protein-coding genes that were not previously shown to be associated with paclitaxel response. As only five genes showed differential mRNA expression, the remainder would not have been detected solely

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

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    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.

  13. Co-treatment with BEZ235 Enhances Sensitivity of BRCA1-negative Breast Cancer Cells to Olaparib.

    Science.gov (United States)

    Yi, Yong Weon; Park, Jeong-Soo; Kwak, Sahng-June; Seong, Yeon-Sun

    2015-07-01

    The poly(ADP-ribose) polymerase (PARP) inhibitor, olaparib has been reported as having preferential anti-proliferative effects on breast cancer 1 (BRCA1)-deficient breast and ovarian cancer cells and was recently approved by the US Food and Drug Administration (FDA) for advanced, BRCA1-mutated ovarian cancer. Herein, we show that BEZ235, a protein kinase inhibitor, enhanced the tumor cell-killing effect of olaparib in BRCA1-mutated breast cancer cells in vitro. BEZ235 reduced olaparib-induced phosphorylation of p53 binding protein 1 (53BP1) and 53BP1 foci formation, as well as phosphorylation of AKT (S473). Long-term colony-formation assay revealed more strong synergistic effects of this combination in SUM149PT and MDA-MB-468 breast cancer cell lines. BEZ235 treatment combined with olaparib may be a candidate for effective therapeutic treatment of BRCA1-mutated breast cancer. Copyright© 2015 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

  14. The JAK2 inhibitors CEP-33779 and NVP-BSK805 have high P-gp inhibitory activity and sensitize drug-resistant cancer cells to vincristine.

    Science.gov (United States)

    Cheon, Ji Hyun; Kim, Kyeong Seok; Yadav, Dharmendra Kumar; Kim, Mihyun; Kim, Hyung Sik; Yoon, Sungpil

    2017-09-02

    P-glycoprotein (P-gp) is overexpressed in cancer cells in order to pump out chemotherapeutic drugs, and is one of the major mechanisms responsible for multidrug resistance (MDR). It is important to identify P-gp inhibitors with low toxicity to normal cells in order to increase the efficacy of anti-cancer drugs. Previously, a JAK2 inhibitor CEP-33779 demonstrated inhibitory actions against P-gp and an ability to sensitize drug-resistant cancer cells to treatment. In the present study, we tested another JAK2 inhibitor NVP-BSK805 for P-gp inhibitory activity. In molecular docking simulation modeling, NVP-BSK805 showed higher binding affinity docking scores against a P-gp member (ABCB1) than CEP-33779 did. Furthermore, we found that lower doses of NVP-BSK805 are required to inhibit P-gp in comparison with that of CEP-33779 or verapamil (an established P-gp inhibitor) in KBV20C cells, suggesting that NVP-BSK805 has higher specificity. NVP-BSK805, CEP-33779, and verapamil demonstrated similar abilities to sensitize KBV20C cells to vincristine (VIC) treatment. Our results suggested that the JAK2 inhibitors were able to inhibit P-gp pump-action via a direct binding mechanism, similar to verapamil. However, JAK2 inhibitor-induced sensitization was not observed in VIC-treated sensitive KB parent cells, suggesting that these effects are specific to resistant cancer cells. FACS, western-blot, and annexin V analyses were used to further investigate the mechanism of action of JAK2 inhibitors in VIC-treated KBV20C cells. Both CEP-33779 and NVP-BSK805 induced the sensitization of KBV20C cells to VIC treatment via the same mechanisms; they each caused a reduction in cell viability, increased G2 arrest, and upregulated expression of the DNA damaging protein pH2AX when used as co-treatments with VIC. These findings indicate that inhibition of JAK2 may be a promising target in the treatment of cancers that are resistant to anti-mitotic drugs. Copyright © 2017 Elsevier Inc. All rights

  15. Inhibition of the mitochondrial pyrimidine biosynthesis enzyme dihydroorotate dehydrogenase by doxorubicin and brequinar sensitizes cancer cells to TRAIL-induced apoptosis.

    Science.gov (United States)

    He, T; Haapa-Paananen, S; Kaminskyy, V O; Kohonen, P; Fey, V; Zhivotovsky, B; Kallioniemi, O; Perälä, M

    2014-07-03

    Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a promising agent in selectively killing tumor cells. However, TRAIL monotherapy has not been successful as many cancer cells are resistant to TRAIL. Chemotherapeutic agents, such as doxorubicin have been shown to act synergistically with TRAIL, but the exact mechanisms of actions are poorly understood. In this study, we performed high-throughput small interfering RNA screening and genome-wide gene expression profiling on doxorubicin-treated U1690 cells to explore novel mechanisms underlying doxorubicin-TRAIL synergy. The screening and expression profiling results were integrated and dihydroorotate dehydrogenase (DHODH) was identified as a potential candidate. DHODH is the rate-limiting enzyme in the pyrimidine synthesis pathway, and its expression was downregulated by doxorubicin. We demonstrated that silencing of DHODH or inhibition of DHODH activity by brequinar dramatically increased the sensitivity of U1690 cells to TRAIL-induced apoptosis both in 2D and 3D cultures, and was accompanied by downregulation of c-FLIPL as well as by mitochondrial depolarization. In addition, uridine, an end product of the pyrimidine synthesis pathway was able to rescue the sensitization effects initiated by both brequinar and doxorubicin. Furthermore, several other cancer cell lines, LNCaP, MCF-7 and HT-29 were also shown to be sensitized to TRAIL by brequinar. Taken together, our findings have identified a novel protein target and its inhibitor, brequinar, as a potential agent in TRAIL-based combinatorial cancer therapy and highlighted for the first time the importance of mitochondrial DHODH enzyme and pyrimidine pathway in mediating TRAIL sensitization in cancer cells.

  16. NPRL2 sensitizes human non-small cell lung cancer (NSCLC cells to cisplatin treatment by regulating key components in the DNA repair pathway.

    Directory of Open Access Journals (Sweden)

    Gitanjali Jayachandran

    2010-08-01

    Full Text Available NPRL2, one of the tumor suppressor genes residing in a 120-kb homozygous deletion region of human chromosome band 3p21.3, has a high degree of amino acid sequence homology with the nitrogen permease regulator 2 (NPR2 yeast gene, and mutations of NPRL2 in yeast cells are associated with resistance to cisplatin-mediated cell killing. Previously, we showed that restoration of NPRL2 in NPRL2-negative and cisplatin-resistant cells resensitize lung cancer cells to cisplatin treatment in vitro and in vivo. In this study, we show that sensitization of non-small cell lung cancer (NSCLC cells to cisplatin by NPRL2 is accomplished through the regulation of key components in the DNA-damage checkpoint pathway. NPRL2 can phosphorylate ataxia telangiectasia mutated (ATM kinase activated by cisplatin and promote downstream gamma-H2AX formation in vitro and in vivo, which occurs during apoptosis concurrently with the initial appearance of high-molecular-weight DNA fragments. Moreover, this combination treatment results in higher Chk1 and Chk2 kinase activity than does treatment with cisplatin alone and can activate Chk2 in pleural metastases tumor xenograft in mice. Activated Chk1 and Chk2 increase the expression of cell cycle checkpoint proteins, including Cdc25A and Cdc25C, leading to higher levels of G2/M arrest in tumor cells treated with NPRL2 and cisplatin than in tumor cells treated with cisplatin only. Our results therefore suggest that ectopic expression of NPRL2 activates the DNA damage checkpoint pathway in cisplatin-resistant and NPRL2-negative cells; hence, the combination of NPRL2 and cisplatin can resensitize cisplatin nonresponders to cisplatin treatment through the activation of the DNA damage checkpoint pathway, leading to cell arrest in the G2/M phase and induction of apoptosis. The direct implication of this study is that combination treatment with NPRL2 and cisplatin may overcome cisplatin resistance and enhance therapeutic efficacy.

  17. NPRL2 Sensitizes Human Non-Small Cell Lung Cancer (NSCLC) Cells to Cisplatin Treatment by Regulating Key Components in the DNA Repair Pathway

    Science.gov (United States)

    Wang, Bingbing; Roth, Jack A.; Ji, Lin

    2010-01-01

    NPRL2, one of the tumor suppressor genes residing in a 120-kb homozygous deletion region of human chromosome band 3p21.3, has a high degree of amino acid sequence homology with the nitrogen permease regulator 2 (NPR2) yeast gene, and mutations of NPRL2 in yeast cells are associated with resistance to cisplatin-mediated cell killing. Previously, we showed that restoration of NPRL2 in NPRL2-negative and cisplatin-resistant cells resensitize lung cancer cells to cisplatin treatment in vitro and in vivo. In this study, we show that sensitization of non-small cell lung cancer (NSCLC) cells to cisplatin by NPRL2 is accomplished through the regulation of key components in the DNA-damage checkpoint pathway. NPRL2 can phosphorylate ataxia telangiectasia mutated (ATM) kinase activated by cisplatin and promote downstream γ-H2AX formation in vitro and in vivo, which occurs during apoptosis concurrently with the initial appearance of high-molecular-weight DNA fragments. Moreover, this combination treatment results in higher Chk1 and Chk2 kinase activity than does treatment with cisplatin alone and can activate Chk2 in pleural metastases tumor xenograft in mice. Activated Chk1 and Chk2 increase the expression of cell cycle checkpoint proteins, including Cdc25A and Cdc25C, leading to higher levels of G2/M arrest in tumor cells treated with NPRL2 and cisplatin than in tumor cells treated with cisplatin only. Our results therefore suggest that ectopic expression of NPRL2 activates the DNA damage checkpoint pathway in cisplatin-resistant and NPRL2-negative cells; hence, the combination of NPRL2 and cisplatin can resensitize cisplatin nonresponders to cisplatin treatment through the activation of the DNA damage checkpoint pathway, leading to cell arrest in the G2/M phase and induction of apoptosis. The direct implication of this study is that combination treatment with NPRL2 and cisplatin may overcome cisplatin resistance and enhance therapeutic efficacy. PMID:20700484

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

    Directory of Open Access Journals (Sweden)

    Kim Phillip

    2011-12-01

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

  19. Genetic Alterations in the PI3K/Akt Signaling Pathway Confer Sensitivity of Thyroid Cancer Cells to Therapeutic Targeting of Akt and mTOR

    Science.gov (United States)

    Liu, Dingxie; Hou, Peng; Liu, Zhi; Wu, Guojun; Xing, Mingzhao

    2009-01-01

    We investigated the genotype-dependent therapeutic potential of targeting the PI3K/Akt pathway for thyroid cancer. Proliferation of TPC1, Hth7, FTC133, OCUT1, K1, and BCPAP cells that harbored PI3K/Akt-activating genetic alterations was potently inhibited by the Akt inhibitor perifosine whereas SW1736, Hth74, WRO, KAT18, and TAD2 cells that harbored no genetic alterations had no or only modest responses. Inhibition of Akt phosphorylation by perifosine was seen in these cells. Genetic-dependent apoptosis was induced by perifosine in cells selectively tested. Similarly, potent inhibition of cell proliferation by the mTOR inhibitor temsirolimus occurred in virtually all the cells harboring genetic alterations whereas modest inhibition was seen in some of the cells not harboring genetic alterations. Temsirolimus inhibited the phosphorylation of p70S6K, a substrate of mTOR. Knockdown of Akt1/2 or mTOR by shRNA approach inhibited the proliferation and colony formation of FTC133 and OCUT1 cells that harbored genetic alterations in the PI3K/Akt pathway but had no effect on SW1736 and KAT18 cells that did not. Transfection with PIK3CA mutants greatly sensitized SW1736 cells to perifosine and temsirolimus. Growth of xenograft tumors derived from FTC133 cells but not SW1736 cells in nude mice was dramatically inhibited by perifosine. Thus, this work for the first time demonstrates that genetic alterations in the PI3K/Akt pathway confer thyroid cancer cells addiction to this pathway and their sensitivity to inhibition by targeting Akt and mTOR. This genotype-based targeting of the PI3K/Akt pathway using Akt and mTOR inhibitors may offer an effective therapeutic strategy for thyroid cancer and warrants further studies. PMID:19706758

  20. 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.

  1. 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.

  2. 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

    Tissue inhibitor of metalloproteinases-1 (TIMP-1) has been suggested as a marker of prognosis and response to treatment in breast cancer. In vitro, TIMP-1 can regulate shedding of the extracellular domain of HER2 and signalling via the Akt pathway, and we hypothesize that TIMP-1 therefore can...... affect sensitivity to the HER2-targeting drugs trastuzumab and lapatinib. SK-BR-3 human breast cancer cells were stably transfected with TIMP-1, characterized with regard to TIMP-1 protein expression, proliferation, and functionality of the secreted TIMP-1, and the sensitivity to trastuzumab...... of TIMP-1 protein. Western blotting showed that the activation of Akt, PTEN, and HER2 as well as ADAM10 was similar in all clones. In conclusion, in this model, TIMP-1 overexpression does not affect HER2 cleavage by ADAM10 or signalling via the Akt pathway, and TIMP-1 does not influence sensitivity...

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-06-20

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

  4. Dual epidermal growth factor receptor and vascular endothelial growth factor receptor inhibition with vandetanib sensitizes bladder cancer cells to cisplatin in a dose- and sequence-dependent manner.

    Science.gov (United States)

    Flaig, Thomas W; Su, Lih-Jen; McCoach, Caroline; Li, Yuan; Raben, David; Varella-Garcia, Marileila; Bemis, Lynne T

    2009-06-01

    To investigate the activity of the combination of vandetanib and cytotoxic agents using in vitro models of bladder cancer, as modern chemotherapy regimens are built around cisplatin, with gemcitabine or a taxane such as docetaxel also commonly added in combination for the treatment of advanced bladder cancer. Human bladder cancer cells HTB3, HT1376, J82, RT4, CRL1749, T24, SUP and HTB9 were cultured. The activity of gefitinib (ZD1839) and vandetanib (ZD6474) was assessed in these eight bladder cancer cell lines with a tetrazolium-based assay of cell viability. RT4 bladder cancer cells, determined to have moderate cisplatin resistance and also moderate sensitivity to vandetanib, were treated with vandetanib and cisplatin. RT4 and T24 cells were treated with six different regimens. The apoptosis and cell-cycle analysis were studied by flow cytometry. Expression of p21 and p27 was detected by Western blotting. Fluorescence in situ hybridization (FISH) analysis of epidermal growth factor receptor (EGFR) and human epidermal growth factor receptor 2 was performed for all cell lines. At equal concentrations, vandetanib was a more potent inhibitor of cell viability, compared to gefitinib. At vandetanib concentrations of cell-cycle distribution showed that vandetanib treatment induced G1 arrest at high concentrations, but not at lower concentrations. High-concentration treatment was associated with increased levels of the cyclin-dependent kinase p27. FISH analysis showed that there was a low level of genomic gain, and no gene amplification. Mutational analysis of exons 18, 19, and 21 of EGFR in each cell line revealed no mutation. Vandetanib has synergistic activity when given at low concentration with cytotoxic chemotherapy. The addition of vandetanib to cisplatin-based chemotherapy regimens merits further study.

  5. Gene expression patterns that predict sensitivity to epidermal growth factor receptor tyrosine kinase inhibitors in lung cancer cell lines and human lung tumors

    Directory of Open Access Journals (Sweden)

    Haura Eric B

    2006-11-01

    Full Text Available Abstract Background Increased focus surrounds identifying patients with advanced non-small cell lung cancer (NSCLC who will benefit from treatment with epidermal growth factor receptor (EGFR tyrosine kinase inhibitors (TKI. EGFR mutation, gene copy number, coexpression of ErbB proteins and ligands, and epithelial to mesenchymal transition markers all correlate with EGFR TKI sensitivity, and while prediction of sensitivity using any one of the markers does identify responders, individual markers do not encompass all potential responders due to high levels of inter-patient and inter-tumor variability. We hypothesized that a multivariate predictor of EGFR TKI sensitivity based on gene expression data would offer a clinically useful method of accounting for the increased variability inherent in predicting response to EGFR TKI and for elucidation of mechanisms of aberrant EGFR signalling. Furthermore, we anticipated that this methodology would result in improved predictions compared to single parameters alone both in vitro and in vivo. Results Gene expression data derived from cell lines that demonstrate differential sensitivity to EGFR TKI, such as erlotinib, were used to generate models for a priori prediction of response. The gene expression signature of EGFR TKI sensitivity displays significant biological relevance in lung cancer biology in that pertinent signalling molecules and downstream effector molecules are present in the signature. Diagonal linear discriminant analysis using this gene signature was highly effective in classifying out-of-sample cancer cell lines by sensitivity to EGFR inhibition, and was more accurate than classifying by mutational status alone. Using the same predictor, we classified human lung adenocarcinomas and captured the majority of tumors with high levels of EGFR activation as well as those harbouring activating mutations in the kinase domain. We have demonstrated that predictive models of EGFR TKI sensitivity can

  6. IMPAIRED SHP2-MEDIATED ERK ACTIVATION CONTRIBUTES TO GEFITINIB SENSITIVITY OF LUNG CANCER CELLS WITH EGFR-ACTIVATING MUTATIONS

    OpenAIRE

    Lazzara, Matthew J.; Lane, Keara; Chan, Richard; Jasper, Paul J; Yaffe, Michael B.; Sorger, Peter K.; Jacks, Tyler; Neel, Benjamin G.; Lauffenburger, Douglas A.

    2010-01-01

    Most non-small cell lung cancers (NSCLC) display elevated expression of epidermal growth factor receptor (EGFR), but response to EGFR kinase inhibitors is predominantly limited to NSCLC harboring EGFR-activating mutations. These mutations are associated with increased activity of survival pathways including PI3K/AKT and STAT3/5. We report that EGFR-activating mutations also surprisingly lead to decreased ability to activate ERK compared to wild-type EGFR. In NSCLC cells and mouse embryonic fi...

  7. Inhibition of Wee1 sensitizes cancer cells to anti-metabolite chemotherapeutics in vitro and in vivo, independent of p53 functionality

    Science.gov (United States)

    Linden, Annemie A. Van; Baturin, Dmitry; Ford, James B.; Fosmire, Susan P.; Gardner, Lori; Korch, Christopher; Reigan, Philip; Porter, Christopher C.

    2013-01-01

    Inhibition of Wee1 is emerging as a novel therapeutic strategy for cancer, and some data suggest that cells with dysfunctional p53 are more sensitive to Wee1 inhibition combined with conventional chemotherapy than those with functional p53. We and others found that Wee1 inhibition sensitizes leukemia cells to cytarabine. Thus, we sought to determine whether chemosensitization by Wee1 inhibition is dependent on p53 dysfunction and whether combining Wee1 inhibition is tolerable and effective in vivo. Synergistic inhibition of proliferation with a Wee1 inhibitor in clinical development, MK1775, and cytarabine was observed in all acute myeloid leukemia (AML) cell lines tested, regardless of p53 functionality. Mechanistic studies indicate that inhibition of Wee1 abrogates the S-phase checkpoint and augments apoptosis induced by cytarabine. In AML and lung cancer cell lines, genetic disruption of p53 did not alter the cells' enhanced sensitivity to antimetabolites with Wee1 inhibition. Lastly, mice with AML were treated with cytarabine and/or MK1775. The combination of MK1775 and cytarabine was well-tolerated in mice and enhanced the anti-leukemia effects of cytarabine, including survival. Thus, inhibition of Wee1 sensitizes hematologic and solid tumor cell lines to antimetabolite chemotherapeutics, whether p53 is functional or not, suggesting that the use of p53 mutation as a predictive biomarker for response to Wee1 inhibition may be restricted to certain cancers and/or chemotherapeutics. These data provide preclinical justification for testing MK1775 and cytarabine in patients with leukemia. PMID:24121103

  8. Metformin sensitizes human bladder cancer cells to TRAIL-induced apoptosis through mTOR/S6K1-mediated downregulation of c-FLIP.

    Science.gov (United States)

    Zhang, Tao; Wang, Xinyang; He, Dalin; Jin, Xunbo; Guo, Peng

    2014-09-01

    Metformin, an oral antidiabetic agent, has been reported to potentiate chemotherapeutic-induced cytotoxicity. In this study, we investigated the effects and molecular mechanisms of metformin in sensitizing tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-induced apoptosis in human bladder cancer cells. Metformin alone did not induce apoptosis, but markedly potentiated TRAIL-induced apoptosis in 253J and RT4 bladder cancer cells. To elucidate the underlying mechanism, we examined the modulatory effects of metformin on the key components of the TRAIL signaling pathway and found that metformin did not alter the expression levels of death receptor 4 (DR4) and death receptor 5 (DR5), but significantly reduced the cellular Fas-associated death domain (FADD)-like interleukin-1β-converting enzyme (FLICE) inhibitory protein (c-FLIP) levels, contributing toward the sensitization to TRAIL. Further experiments showed that metformin did not affect the mRNA level, proteasomal degradation, and protein stability of c-FLIPL. However, metformin inhibited the mTOR/S6K1 pathway in 253J and RT4 cells, which usually regulates protein translation; moreover, knockdown of S6K1 effectively reduced the levels of c-FLIPL, indicating that metformin downregulates c-FLIP through inhibition of the mTOR/S6K1 pathway. In addition, AMP-activated protein kinase (AMPK) inhibitor compound C did not prevent the inhibitory effects of metformin on the mTOR/S6K1 pathway and metformin-mediated sensitization to TRAIL. Taken together, our results indicate that metformin sensitizes human bladder cancer cells to TRAIL-induced apoptosis through downregulation of c-FLIP, which is mediated by the mTOR/S6K1 pathway, but independent of AMPK; furthermore, these findings provide a rationale for the combined application of metformin with TRAIL in the treatment of bladder cancer.

  9. Conveying a newly designed hydrophilic anti-human thymidylate synthase peptide to cisplatin resistant cancer cells: are pH-sensitive liposomes more effective than conventional ones?

    Science.gov (United States)

    Sacchetti, Francesca; D'Arca, Domenico; Genovese, Filippo; Pacifico, Salvatore; Maretti, Eleonora; Hanuskova, Miriam; Iannuccelli, Valentina; Costi, Maria Paola; Leo, Eliana

    2017-03-01

    LR-peptide, a novel hydrophilic peptide synthetized and characterized in previous work, is able to reduce the multi-drug resistance response in cisplatin (cDPP) resistant cancer cells by inhibiting human thymidylate synthase (hTS) overexpressed in several tumors, including ovarian and colon-rectal cancers, but it is unable to enter the cells spontaneously. The aim of this work was to design and characterize liposomal vesicles as drug delivery systems for the LR peptide, evaluating the possible benefits of the pH-responsive feature in improving intracellular delivery. For this purpose, conventional and pH-sensitive liposomes were formulated, compared regarding their physical-chemical properties (size, PDI, morphology, in vitro stability and drug release) and studied for in vitro cytotoxicity against a cDDP-resistant cancer cells. Results indicated that LR peptide was successfully encapsulated in both liposomal formulations but at short incubation time only LR loaded pH-sensitive liposomes showed cell inhibition activity while for long incubation time the two kinds of liposomes demonstrated the same efficacy. Data provide evidence that acidic pH-triggered liposomal delivery is able to significantly reduce the time required by the systems to deliver the drug to the cells without inducing an enhancement of the efficacy of the drug.

  10. Differential mTOR pathway profiles in bladder cancer cell line subtypes to predict sensitivity to mTOR inhibition.

    Science.gov (United States)

    Hau, Andrew M; Nakasaki, Manando; Nakashima, Kazufumi; Krish, Goutam; Hansel, Donna E

    2017-10-01

    Molecular classification of bladder cancer has been increasingly proposed as a potential tool to predict clinical outcomes and responses to chemotherapy. Here we focused on mechanistic target of rapamycin (mTOR) inhibition as a chemotherapeutic strategy and characterized the expression profile of mTOR signaling targets in representative bladder cancer cell lines from basal, luminal, and either basal/luminal ("non-type") molecular subtypes. Protein and mRNA expression of mTOR signaling components from representative luminal (RT4 and RT112), basal (SCaBER and 5637), and nontype (T24 and J82) bladder cancer cell line subtypes were determined by Western blot and database mining analysis of the Cancer Cell Line Encyclopedia. Cell viability following treatment with either, Torin-2 or KU-0063794, 2 dual mTOR complex 1/2 inhibitors, was determined by MTT assay. Immunoblot analysis of cells treated with Torin-2 or KU-0063794 was performed to determine the effects of mTOR inhibition on expression and phosphorylation status of mTOR signaling components, Akt, 4E-BP1, and ribosomal protein S6. Molecular subtypes of bladder cancer cell lines each exhibited a distinct pattern of expression of mTOR-associated genes and baseline phosphorylation level of Akt and 4E-BP1. Cells with low levels of Akt Ser-473 phosphorylation were more resistant to the cytotoxic effects of mTOR inhibition with Torin-2, but not KU-0063794. Exposure to Torin-2 and KU-0063794 both potently and rapidly inhibited phosphorylation of Akt Ser-473 and Thr-308, and 4E-BP1 T37/46 in cell lines that included basal and nontype subtypes. Differential gene expression and protein activity associated with mTOR signaling is observed among bladder cancer cell lines stratified into basal, luminal, and nontype subtypes. Urothelial carcinomas characterized by high baseline Akt Ser-473 phosphorylation may be best suited for targeted mTOR therapies. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. 1,3-Bis(2-chloroethyl)-1-nitrosourea enhances the inhibitory effect of resveratrol on 5-fluorouracil sensitive/resistant colon cancer cells.

    Science.gov (United States)

    Das, Dipon; Preet, Ranjan; Mohapatra, Purusottam; Satapathy, Shakti Ranjan; Kundu, Chanakya Nath

    2013-11-14

    To study the mechanism of 5-fluorouracil (5-FU) resistance in colon cancer cells and to develop strategies for overcoming such resistance by combination treatment. We established and characterized a 5-FU resistance (5-FU-R) cell line derived from continuous exposure (25 μmol/L) to 5-FU for 20 wk in 5-FU sensitive HCT-116 cells. The proliferation and expression of different representative apoptosis and anti-apoptosis markers in 5-FU sensitive and 5-FU resistance cells were measured by the MTT assay and by Western blotting, respectively, after treatment with Resveratrol (Res) and/or 1,3-Bis(2-chloroethyl)-1-nitrosourea (BCNU). Apoptosis and cell cycle arrest was measured by 4',6'-diamidino-2-phenylindole hydrochloride staining and fluorescence-activated cell sorting analysis, respectively. The extent of DNA damage was measured by the Comet assay. We measured the visible changes in the DNA damage/repair cascade by Western blotting. The widely used chemotherapeutic agents BCNU and Res decreased the growth of 5-FU sensitive HCT-116 cells in a dose dependent manner. Combined application of BCNU and Res caused more apoptosis in 5-FU sensitive cells in comparison to individual treatment. In addition, the combined application of BCNU and Res caused a significant decrease of major DNA base excision repair components in 5-FU sensitive cells. We established a 5-FU resistance cell line (5-FU-R) from 5-FU-sensitive HCT-116 (mismatch repair deficient) cells that was not resistant to other chemotherapeutic agents (e.g., BCNU, Res) except 5-FU. The 5-FU resistance of 5-FU-R cells was assessed by exposure to increasing concentrations of 5-FU followed by the MTT assay. There was no significant cell death noted in 5-FU-R cells in comparison to 5-FU sensitive cells after 5-FU treatment. This resistant cell line overexpressed anti-apoptotic [e.g., AKT, nuclear factor κB, FLICE-like inhibitory protein), DNA repair (e.g., DNA polymerase beta (POL-β), DNA polymerase eta (POLH), protein

  12. Suppression of PC-1/PrLZ sensitizes prostate cancer cells to ionizing radiation by attenuating DNA damage repair and inducing autophagic cell death.

    Science.gov (United States)

    Shang, Zeng-Fu; Wei, Qiang; Yu, Lan; Huang, Fang; Xiao, Bei-Bei; Wang, Hongtao; Song, Man; Wang, Li; Zhou, Jianguang; Wang, Jian; Li, Shanhu

    2016-09-20

    Radiotherapy is promising and effective for treating prostate cancer but the addition of a tumor cell radiosensitizer would improve therapeutic outcomes. PC-1/PrLZ, a TPD52 protein family member is frequently upregulated in advanced prostate cancer cells and may be a biomarker of aggressive prostate cancer. Therefore, we investigated the potential role of PC-1/PrLZ for increasing radioresistance in human prostate cancer cell lines. Growth curves and survival assays after g-ray irradiation confirmed that depletion of endogenous PC-1/PrLZ significantly increased prostate cancer cell radiosensitivity. Irradiation (IR) increased PC-1/PrLZ expression in a dose- and time-dependent manner and increased radiosensitivity in PC-1/PrLZ-suppressed cells was partially due to decreased DNA double strand break (DBS) repair which was measured with comet and gH2AX foci assays. Furthermore, depletion of PC-1/PrLZ impaired the IR-induced G2/M checkpoint, which has been reported to be correlate with radioresistance in cancer cells. PC-1/PrLZ-deficient cells exhibited higher level of autophagy when compared with control cells. Thus, specific inhibition of PC-1/PrLZ might provide a novel therapeutic strategy for radiosensitizing prostate cancer cells.

  13. Recombinant expression of different mutant K-ras gene in pancreatic cancer Bxpc-3 cells and its effects on chemotherapy sensitivity.

    Science.gov (United States)

    Shao, TengFei; Zheng, YuanTing; Zhao, Bei; Li, Tao; Cheng, KeGuang; Cai, WeiMin

    2014-10-01

    K-ras is a member of ras gene family which is involved in cell survival, proliferation and differentiation. When a mutation occurs in ras gene, the activation of Ras proteins may be prolonged to induce oncogenesis. However, the relationship between K-ras mutation and clinical outcomes in pancreatic cancer patients treated with chemotherapy agents is still under debate. In this study, we constructed five pAcGFP1-C3 plasmids for different types of K-ras gene (WT, G12V, G12R, G12D, and G13D) and stably transfected human pancreatic cancer Bxpc-3 cells with these genes. The wild type and mutant clones showed a comparable growth and expression of K-Ras-GFP fusion protein. The expression of some K-ras mutations resulted in a reduced sensitivity to gefitinib, 5-FU, docetaxel and gemcitabine, while showed no effects on erlotinib or cisplatin. Moreover, compared with the wild type clone, K-Ras downstream signals (phospho-Akt and/or phospho-Erk) were increased in K-ras mutant clones. Interestingly, different types of K-ras mutation had non-identical K-Ras downstream signal activities and drug responses. Our results are the first to reveal the relationship between different K-ras mutation and drug sensitivities of these anti-cancer drugs in pancreatic cancer cells in vitro.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2011-01-28

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

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

    Directory of Open Access Journals (Sweden)

    Mohamed K Hassan

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

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

    Science.gov (United States)

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

    2008-01-01

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

  17. Human Mena+11a isoform serves as a marker of epithelial phenotype and sensitivity to epidermal growth factor receptor inhibition in human pancreatic cancer cell lines.

    Science.gov (United States)

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

    2008-08-01

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

  18. Arsenic trioxide re-sensitizes ERα-negative breast cancer cells to endocrine therapy by restoring ERα expression in vitro and in vivo.

    Science.gov (United States)

    Zhang, Weijie; Wang, Liuxing; Fan, Qingxia; Wu, Xinai; Wang, Feng; Wang, Rui; Ma, Zhijun; Yang, Jianhua; Lu, Shih Hsin

    2011-09-01

    Approximately one-third of breast cancers lack estrogen receptor α (ERα) because of the hypermethylation of the CpG island in the receptor's promoter. These tumors are associated with poorer histological differentiation, a higher growth fraction, are rarely responsive to endocrine therapy and have a worse clinical outcome. Thus, re-expression of ERα in ERα-negative breast cancers may restore the sensitivity of antiestrogen therapy. The ERα-negative breast cancer cell line MDA-MB-435s was treated with different concentrations of arsenic trioxide (As2O3). MS-PCR was used to detect the change in the methylation status of ERα. RT-PCR, immunohistochemistry and Western blot analyses were used to detect changes in the mRNA and protein expression of DNA methyl-transferase-1 (DNMT1) and ERα. Cell proliferation was examined using the MTT assay. A xenograft model in nude mice was used to further examine the results we observed in vitro. The ERα gene was demethylated after As2O3 treatment of MDA-MB-435s cells. RT-PCR, immunohistochemistry and Western blot analyses revealed that DNMT1 expression was inhibited and ERα was re-expressed in a concentration-dependent manner after As2O3 treatment. The MTT assay showed that cell proliferation was significantly suppressed after exposure to different concentrations of As2O3. Addition of tamoxifen (TAM) further suppressed levels of cell proliferation. In vivo, the xenograft tumor volumes of As2O3-treated mice were smaller than those observed in untreated and TAM-treated mice. Treatment with a combination of As2O3+TAM resulted in further suppression. As2O3 can act as a demethylation agent to restore ERα expression in ERα-negative breast cancer cells and re-sensitize these cells to endocrine therapy in vitro and in vivo.

  19. Nomograms Predicting Platinum Sensitivity, Progression-Free Survival, and Overall Survival Using Pretreatment Complete Blood Cell Counts in Epithelial Ovarian Cancer.

    Science.gov (United States)

    Paik, E Sun; Sohn, Insuk; Baek, Sun-Young; Shim, Minhee; Choi, Hyun Jin; Kim, Tae-Joong; Choi, Chel Hun; Lee, Jeong-Won; Kim, Byoung-Gie; Lee, Yoo-Young; Bae, Duk-Soo

    2017-07-01

    This study was conducted to evaluate the prognostic significance of pre-treatment complete blood cell count (CBC), including white blood cell (WBC) differential, in epithelial ovarian cancer (EOC) patients with primary debulking surgery (PDS) and to develop nomograms for platinum sensitivity, progression-free survival (PFS), and overall survival (OS). We retrospectively reviewed the records of 757 patients with EOC whose primary treatment consisted of surgical debulking and chemotherapy at Samsung Medical Center from 2002 to 2012. We subsequently created nomograms for platinum sensitivity, 3-year PFS, and 5-year OS as prediction models for prognostic variables including age, stage, grade, cancer antigen 125 level, residual disease after PDS, and pre-treatment WBC differential counts. The models were then validated by 10-fold cross-validation (CV). In addition to stage and residual disease after PDS, which are known predictors, lymphocyte and monocyte count were found to be significant prognostic factors for platinum-sensitivity, platelet count for PFS, and neutrophil count for OS on multivariate analysis. The area under the curves of platinum sensitivity, 3-year PFS, and 5-year OS calculated by the 10-fold CV procedure were 0.7405, 0.8159, and 0.815, respectively. Prognostic factors including pre-treatment CBC were used to develop nomograms for platinum sensitivity, 3-year PFS, and 5-year OS of patients with EOC. These nomograms can be used to better estimate individual outcomes.

  20. 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.

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

    Directory of Open Access Journals (Sweden)

    Alok Pant

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

  2. Sensitization of androgen refractory prostate cancer cells to anti-androgens through re-expression of epigenetically repressed androgen receptor - Synergistic action of quercetin and curcumin.

    Science.gov (United States)

    Sharma, Vikas; Kumar, Lokesh; Mohanty, Sujit K; Maikhuri, Jagdamba P; Rajender, Singh; Gupta, Gopal

    2016-08-15

    Epigenetic repression of Androgen Receptor (AR) gene by hypermethylation of its promoter causes resistance in prostate cancer (CaP) to androgen deprivation therapy with anti-androgens. Some dietary phytocompounds like quercetin (Q) and curcumin (C) with reported DNMT-inhibitory activity were tested for their ability to re-express the AR in AR-negative CaP cell lines PC3 and DU145. Combined treatment with Q+C was much more effective than either Q or C in inhibiting DNMT, causing global hypomethylation, restoring AR mRNA and protein levels and causing apoptosis via mitochondrial depolarization of PC3 and DU145. The functional AR protein expressed in Q+C treated cells sensitized them to dihydrotestosterone (DHT)-induced proliferation, bicalutamide-induced apoptosis, bound to androgen response element to increase luciferase activity in gene reporter assay and was susceptible to downregulation by AR siRNA. Bisulfite sequencing revealed high methylation of AR promoter CpG sites in AR-negative DU145 and PC3 cell lines that was significantly demethylated by Q+C treatment, which restored AR expression. Notable synergistic effects of Q+C combination in re-sensitizing androgen refractory CaP cells to AR-mediated apoptosis, their known safety in clinical use, and epidemiological evidences relating their dietary consumption with lower cancer incidences indicate their potential for use in chemoprevention of androgen resistance in prostate cancer. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  3. 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.

    Science.gov (United States)

    Nørgaard, P; Damstrup, L; Rygaard, K; Spang-Thomsen, M; Poulsen, H S

    1996-02-01

    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 and GLC 19 on recurrence after radiotherapy. TGF beta was detected by ELISA and TGF beta receptors by chemical crosslinking to radiolabelled TGF beta 1. Furthermore, TGF beta and TGF beta receptor mRNAs were detected by northern blot analysis. Expression of type II TGF beta receptor mRNA and protein was found in GLC 16 and GLC 19. These cell lines were also growth inhibited by exogenously administrated TGF beta 1. TGF beta 1 mRNA and protein in its latent form was only expressed in the radiotherapy-resistant cell line, GLC 19. The results indicate that disease progression in this patient was paralleled by a gain in sensitivity to the growth inhibition by TGF beta 1 due to type II TGF beta receptor, and a gain of latent TGF beta 1 protein. Lack of type II receptor expression in GLC 14, which was also resistant to growth inhibition by exogenous TGF beta 1, was not due to gross structural changes in the type 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 II receptor.

  4. 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 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...... 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...... 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....

  5. 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.

  6. 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

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

    2015-10-01

    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 delivery to both

  7. 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

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

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    K. Sahin

    2012-01-01

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

  9. 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

  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.

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    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. RNAi-induced K-Ras gene silencing suppresses growth of EC9706 cells and enhances chemotherapy sensitivity of esophageal cancer.

    Science.gov (United States)

    Wang, Xin-Jie; Zheng, Yu-Ling; Fan, Qing-Xia; Zhang, Xu-Dong

    2012-01-01

    To analyze the growth, proliferation, apoptosis, invasiveness and chemotherapy sensitivity of EC9706 cells after K-Ras gene silencing, an expression carrier pSilencer-siK-Ras was constructed, and the EC9706 cell line was transfected using a liposome technique. Six groups were established: Control, siRNA NC (transfected with empty vector pSilencer2.1); Ras siRNA (transfected with pSilencer-siK-Ras2); Paclitaxel; Paclitaxel + siRNA NC; and Ras siRNA +Paclitaxel. After the treatment, RT-PCR, Western blotting, MTT assay, flow cytometry and the Transwell technique were used to assess expression of K-Ras mRNA and protein in EC9706 cells, as well as cell growth, proliferation, apoptosis and invasiveness. The effect of Paclitaxel chemotherapy was also tested. pSilencer-siK-Ras2 effectively down-regulated expression of K-Ras mRNA and protein in EC9706 cells, growth being significantly inhibited. Flow cytometry indicated obvious apoptosis of cells in the experimental group, with arrest in the G1 phase; cell migration ability was also reduced. After pSilencer-siK-Ras2 transfection or the addition of Paclitaxel, EC9706 cells were suppressed to different extents; the suppressive effect was strengthened by combined treatment. The results suggested that RNAi-induced K-Ras gene silencing could enhance chemotherapy sensitivity of esophageal cancer.

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

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    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.

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

    Science.gov (United States)

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

    2012-08-03

    We are interested in investigating the biological activity of chalcones, a major class of compounds found in the beverage kava, in order to develop potent and selective chemopreventive candidates. Consumption of kava in the South Pacific Islands is inversely correlated with cancer incidence, even among smokers. Accordingly, chalcones have anti-cancer activities in animal and cell culture models. To investigate signaling pathways that affect chalcone action we studied a potent analog, (E)-3-(3-hydroxy-4-methoxyphenyl)-1-(3,4,5-trimethoxyphenyl)prop-2-en-1-one (chalcone-24). Chalcone-24 was selected from a series of chalcone analogs that were synthesized based on the structures derived from flavokawain compounds found in kava, and screened in A549 lung cancer cells for induction of cytotoxicity and inhibition of NF-κB, a transcription factor associated with cell survival. Incubation of A549 cells with chalcone-24 resulted in a dose-dependent inhibition of cell viability, inhibition of NF-κB, activation of caspases, and activation of extracellular signal regulated kinase 1/2 (ERK1/2) and c-Jun N-terminal kinase (JNK); ERK1/2 and JNK are mitogen activated protein kinases that play central roles in regulating cell fate. Pharmacological inhibitors of ERK1/2 or JNK increased the sensitivity of A549 cells to chalcone-24-induced cytotoxicity, without affecting NF-κB or caspase activity. These results will help refine the synthesis of chalcone analogs to maximize the combination of actions required to prevent and treat cancer. Copyright © 2012 Elsevier Inc. All rights reserved.

  14. Knockdown of cancerous inhibitor of protein phosphatase 2A may sensitize metastatic castration-resistant prostate cancer cells to cabazitaxel chemotherapy.

    Science.gov (United States)

    Huang, Jinming; Jia, Jiaoyuan; Tong, Qiang; Liu, Jun; Qiu, Jun; Sun, Rong; Yao, Lixin; Yang, Chun

    2015-03-01

    Cancerous inhibitor of protein phosphatase 2A (CIP2A) is a recently identified human oncoprotein that can stabilize some proteins by inhibiting degradation mediated by protein phosphatase 2A (PP2A), and its level in cancer is associated with resistance to chemotherapy. However, whether CIP2A could increase chemoresistance of prostate cancer (PCa) cells to chemotherapeutic agent cabazitaxel remains unclear. To determine whether CIP2A serves as a potential therapeutic target of human PCa, we utilized small interference RNA (siRNA) to knock down CIP2A expression in human PCa cells and analyzed their phenotypic changes. The data demonstrated that CIP2A was significantly elevated in mCRPC cell lines C4-2 and ARCaP(M) at both the mRNA and protein levels. CIP2A silencing led to decreased proliferation and enhanced chemosensitivity and apoptosis to cabazitaxel in human PCa cells, as well as reduced Akt phosphorylation. Our data suggesting critical roles of CIP2A in PCa cells chemoresistance to cabazitaxel and raising the possibility of CIP2A inhibition as a promising approach for chemosensitization of metastatic castration-resistant prostate cancer (mCRPC).

  15. Mechanism of paclitaxel resistance in a human prostate cancer cell line, PC3-PR, and its sensitization by cabazitaxel.

    Science.gov (United States)

    Sobue, Sayaka; Mizutani, Naoki; Aoyama, Yuka; Kawamoto, Yoshiyuki; Suzuki, Motoshi; Nozawa, Yoshinori; Ichihara, Masatoshi; Murate, Takashi

    2016-10-28

    Paclitaxel (PTX) is a microtubule-targeting drug widely used for the treatment of a variety of cancers. However, drug resistance can emerge after a series of treatments, and this can seriously affect the patient's prognosis. Here, we analyzed the mechanism of PTX resistance using a human prostate cancer cell line, PC3, and its PTX-resistant subline, PC3-PR. Compared with PC3, PC3-PR exhibited some unique phenotypes that might be associated with PTX resistance, including decreased expression of acetylated α-tubulin and the cell cycle regulator p21, and increased expression of βIII tubulin, histone deacetylase 6 (HDAC6), and the anti-apoptotic protein Bcl2. The drug exporters MDR1 and MRP1 were not involved in PTX resistance. Although cabazitaxel (CTX), a novel taxoid, has been reported to overcome PTX resistance, its mechanism of action is unknown. We found that treatment of PC3-PR cells with CTX induced expression of acetylated α-tubulin and p21, but not the related regulators p27, p15, and p16 or the Bcl2 family proteins. The pan-HDAC inhibitors trichostatin A and suberanilohydroxamic acid and the HDAC6-specific inhibitor tubacin inhibited PC3-PR proliferation and increased expression of p21 and acetylated α-tubulin in a manner similar to CTX. Our data shed light on the cellular response to PTX and CTX. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. 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.

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

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    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. Sensitive electrochemiluminescence detection of c-Myc mRNA in breast cancer cells on a wireless bipolar electrode.

    Science.gov (United States)

    Wu, Mei-Sheng; Qian, Guang-sheng; Xu, Jing-Juan; Chen, Hong-Yuan

    2012-06-19

    We report an ultrasensitive wireless electrochemiluminescence (ECL) protocol for the detection of a nucleic acid target in tumor cells on an indium tin oxide bipolar electrode (BPE) in a poly(dimethylsiloxane) microchannel. The approach is based on the modification of the anodic pole of the BPE with antisense DNA as the recognition element, Ru(bpy)(3)(2+)-conjugated silica nanoparticles (RuSi@Ru(bpy)(3)(2+)) as the signal amplification tag, and reporter DNA as a reference standard. It employs the hybridization-induced changes of RuSi@Ru(bpy)(3)(2+) ECL efficiency for the specific detection of reporter DNA released from tumor cells. Prior to ECL detection, tumor cells are transfected with CdSe@ZnS quantum dot (QD)-antisense DNA/reporter DNA conjugates. Upon the selective binding of antisense DNA probes to intracellular target mRNA, reporter DNA will be released from the QDs, which indicates the amount of the target mRNA. The proof of concept is demonstrated using a proto-oncogene c-Myc mRNA in MCF-7 cells (breast cancer cell line) as a model target. The wireless ECL biosensor exhibited excellent ECL signals which showed a good linear range over 2 × 10(-16) to 1 × 10(-11) M toward the reporter DNA detection and could accurately quantify c-Myc mRNA copy numbers in living cells. C-Myc mRNA in each MCF-7 cell and LO2 cell was estimated to be 2203 and 13 copies, respectively. This wireless ECL strategy provides great promise in a miniaturized device and may facilitate the achievement of point of care testing.

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

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    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.

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

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    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

  1. Rsf-1 Influences the Sensitivity of Non-Small Cell Lung Cancer to Paclitaxel by Regulating NF-κB Pathway and Its Downstream Proteins

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    Xitao Chen

    2017-12-01

    Full Text Available Background/Aims: The therapeutic efficacy of paclitaxel is hampered by chemotherapeutic resistance in non-small cell lung cancer (NSCLC. Rsf-1 enhanced paclitaxel resistance via nuclear factor-κB (NF-κB in ovarian cancer cells and nasopharyngeal carcinoma. This study assessed the function of Rsf-1 in the modulation of the sensitivity of NSCLC to paclitaxel via the NF-κB pathway. Methods: The mRNA and protein levels of the related genes were quantified by RT-PCR and Western blotting. Rsf-1 silencing was achieved with CRISPR/Cas9 gene editing. Cell cycle, migration and proliferation were tested with flow cytometry, transwell test and CCK8 test. Cell apoptosis was analyzed with flow cytometry and quantification of C-capase3. The parameters of the tumors were measured in H460 cell xenograft mice. Results: Rsf-1 was highly expressed in H460 and H1299 cells. Rsf-1 knockout caused cell arrest at the G1 phase, increased cell apoptosis, and decreased migration and cell proliferation. Rsf-1 knockout increased the inhibition of cell proliferation, the reduction in cell migration and the augment in cell apoptosis in paclitaxel treated H460 and H1299 cells. Rsf-1 knockout further enhanced the paclitaxel-mediated decrease in the volume and weight of the tumors in H460 cell xenograft mice. Helenalin and Rsf-1 knockout decreased the protein levels of p-P65, BcL2, CFLAR, and XIAP; hSNF2H knockout decreased the protein level of NF-κB p-P65 without altering Rsf-1 and p65 protein levels, while Rsf-1 and hSNF2H double knockout decreased the level of NF-κB p-P65, in H1299 and H460 cells. Conclusion: These results demonstrate that Rsf-1 influences the sensitivity of NSCLC to paclitaxel via regulation of the NF-κB pathway and its downstream genes.

  2. Molecular Targets of TRAIL-Sensitizing Agents in Colorectal Cancer

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    Giovanni Monteleone

    2012-06-01

    Full Text Available Tumor necrosis factor (TNF-related apoptosis inducing ligand (TRAIL, a member of the TNF superfamily, interacts with its functional death receptors (DRs and induces apoptosis in a wide range of cancer cell types. Therefore, TRAIL has been considered as an attractive agent for cancer therapy. However, many cancers are resistant to TRAIL-based therapies mainly due to the reduced expression of DRs and/or up-regulation of TRAIL pathway-related anti-apoptotic proteins. Compounds that revert such defects restore the sensitivity of cancer cells to TRAIL, suggesting that combined therapies could help manage neoplastic patients. In this article, we will focus on the TRAIL-sensitizing effects of natural products and synthetic compounds in colorectal cancer (CRC cells and discuss the molecular mechanisms by which such agents enhance the response of CRC cells to TRAIL.

  3. 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

  4. 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.

    Science.gov (United States)

    Villegas-Pineda, Julio César; Toledo-Leyva, Alfredo; Osorio-Trujillo, Juan Carlos; Hernández-Ramírez, Verónica Ivonne; Talamás-Rohana, Patricia

    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. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. 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

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    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.

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

    Science.gov (United States)

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

    2011-12-15

    Over-expression of P-gp, MRP1 and BCRP in tumor cells is one of the important mechanisms leading to multidrug resistance (MDR), which impairs the efficacy of chemotherapy. P-gp, MRP1 and BCRP are ABC (ATP-Binding Cassette) transporters, which can expel a variety of lipophilic anti-cancer drugs and protect tumor cells. During a screening of MDR reversal agents among alkaloids of various structural types, a piperidine alkaloid, piperine (a main piperidine alkaloid in Piper nigurm) was identified as an inhibitor. Piperine can potentiate the cytotoxicity of anti-cancer drugs in resistant sublines, such as MCF-7/DOX and A-549/DDP, which were derived from MCF-7 and A-549 cell lines. At a concentration of 50 μM piperine could reverse the resistance to doxorubicin 32.16 and 14.14 folds, respectively. It also re-sensitized cells to mitoxantrone 6.98 folds. In addition, long-term treatment of cells by piperine inhibits transcription of the corresponding ABC transporter genes. These results suggest that piperine can reverse MDR by multiple mechanisms and it may be a promising lead compound for future studies. Copyright © 2011 Elsevier GmbH. All rights reserved.

  7. 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

  8. Upregulated expression of BCL2, MCM7, and CCNE1 indicate cisplatin-resistance in the set of two human bladder cancer cell lines: T24 cisplatin sensitive and T24R2 cisplatin resistant bladder cancer cell lines

    Directory of Open Access Journals (Sweden)

    Sung Han Kim

    2016-01-01

    Full Text Available Purpose: The mechanism of resistance to cisplatin during treatment of bladder cancer (BC has been a subject of intense investigation in clinical research. This study aims to identify candidate genes associated with resistance to cisplatin, in order to understand the resistance mechanism of BC cells to the drug, by combining the use of microarray profiling, quantitative reverse transcriptionpolymerase chain reaction (RT-PCR, and Western blot analyses. Materials and Methods: The cisplatin sensitive human BC cell line (T24 and the cisplatin resistant BC cell line, T24R2, were used for microarray analysis to determine the differential expression of genes that are significant in cisplatin resistance. Candidate upregulated genes belonging to three well-known cancer-related KEGG (Kyoto Encyclopedia of Genes and Genomes pathways (p53 tumor suppressor, apoptosis, and cell cycle were selected from the microarray data. These candidate genes, differentially expressed in T24 and T24R2, were then confirmed by quantitative RT-PCR and western blot. A fold change ≥2 with a p-value <0.05 was considered significant. Results: A total of 18 significantly upregulated genes were detected in the three selected cancer-related pathways in both microarray and RT-PCR analyses. These genes were PRKAR2A, PRKAR2B, CYCS, BCL2, BIRC3, DFFB, CASP6, CDK6, CCNE1, STEAP3, MCM7, ORC2, ORC5, ANAPC1 , and ANAPC7, CDC7, CDC27 , and SKP1 . Western blot analyses also confirmed the upregulation of BCL2, MCM7, and CCNE1 at the protein level, indicating their crucial association with cisplatin resistance. Conclusions: The BCL2, MCM7 , and CCNE1 genes might play distinctive roles in cisplatin resistance in BC.

  9. 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.

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

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    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

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

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    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.

  12. Endostatin sensitizes p53-deficient non-small-cell lung cancer to genotoxic chemotherapy by targeting DNA-dependent protein kinase catalytic subunit.

    Science.gov (United States)

    Jia, Lin; Lu, Xin-An; Liu, Guanghua; Wang, Shan; Xu, Min; Tian, Yang; Zhang, Shaosen; Fu, Yan; Luo, Yongzhang

    2017-10-01

    Endostatin was discovered as an endogenous angiogenesis inhibitor with broad-spectrum antitumour activities. Although clinical efficacy was observed when endostatin was combined with standard chemotherapy for non-small cell lung cancer (NSCLC), as well as other cancer types, the specific mechanisms underlying the benefit of endostatin are not completely understood. Extensive investigations suggest that endostatin is a multifunctional protein possessing more than anti-angiogenic activity. Here, we found that endostatin exerts a direct chemosensitizing effect on p53-deficient tumour cells. Concomitant treatment with endostatin and genotoxic drugs resulted in therapeutic synergy in both cellular and animal models of p53-deficient NSCLC. Mechanistically, endostatin specifically interacts with DNA-dependent protein kinase catalytic subunit (DNA-PKcs) in tumour cells and suppresses its DNA repair activity. Using isogenic NSCLC cells with different p53 statuses, we discovered that p53-deficient tumour cells show chemoresistance to genotoxic drugs, creating a synthetic dependence on DNA-PKcs-mediated DNA repair. In this setting, endostatin exerted inhibitory effects on DNA-PKcs activity, leading to accumulation of DNA lesions and promotion of the therapeutic effect of genotoxic chemotherapy. In contrast, p53-proficient tumour cells were more sensitive to genotoxic drugs so that DNA-PKcs could be cleaved by drug-activated caspase-3, making DNA-PKcs inhibition less effective during this ongoing apoptotic process. Therefore, our data demonstrate a novel mechanism for endostatin as a DNA-PKcs suppressor, and indicate that combination therapy of endostatin with genotoxic drugs could be a promising treatment strategy for cancer patients with p53-deficient tumours. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

  13. Dye Sensitized Tandem Photovoltaic Cells

    Energy Technology Data Exchange (ETDEWEB)

    Barber, Greg D.

    2009-12-21

    This work provided a new way to look at photoelectrochemical cells and their performance. Although thought of as low efficiency, a the internal efficiency of a 9% global efficiency dye sensitized solar cell is approximately equal to an 18% efficient silicon cell when each is compared to their useful spectral range. Other work undertaken with this contract also reported the first growth oriented titania and perovskite columns on a transparent conducting oxide. Other work has shown than significant performance enhancement in the performance of dye sensitized solar cells can be obtained through the use of coupling inverse opal photonic crystals to the nanocrystalline dye sensitized solar cell. Lastly, a quick efficient method was developed to bond titanium foils to transparent conducting oxide substrates for anodization.

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

    Science.gov (United States)

    Wu, Yifen; Li, Rong; Zhang, Junyi; Wang, Gang; Liu, Bin; Huang, Xiaofang; Zhang, Tao; Luo, Rongcheng

    2015-01-01

    Trastuzumab resistance in HER-2 positive breast cancer cells is closely related to overexpression of both epidermal growth factor receptor (EGFR) and human epidermal receptor (HER-2). SHP-1 has been demonstrated to downregulate tyrosine kinase activity including EGFR via its phosphatase function, but its effect on HER-2 activity is still unknown. Here, we examined the hypothesis that SHP-1 enhances the anticancer efficacy of trastuzumab in EGFR/HER-2 positive breast cancer cells through combining dual inhibition of EGFR and HER-2. Trastuzumab-resistant breast cancer SKBr-3 cells were generated by long-term in vitro culture of SKBr-3cells in the presence of trastuzumab. The SHP-1 was ectopically expressed by stable transfection. The activity and expression of EGFR, HER-2, and downstream signaling pathways were tested by Western blot. Cell viability was examined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, and apoptosis was examined by flow cytometry. The binding between SHP-1 and EGFR/HER-2 was evaluated by immunoprecipitation assay and bimolecular fluorescence complementation. The effects of SHP-1 on tumorigenicity and trastuzumab sensitivity were confirmed via in vivo xenograft model. Trastuzumab-resistant SKBr-3 cells showed aberrant co-expression of EGFR and HER-2. Introduction of wild-type SHP-1 inhibited cell proliferation, clone formation, and promoted the apoptosis induced by trastuzumab. Meanwhile, SHP-1 overexpression reduced phosphorylation levels of EGFR and HER-2 both in parental and trastuzumab-resistant SKBr-3 cells. In vivo study showed an increased antitumor effect of trastuzumab in SHP-1 overexpressed xenografts. At last, we discovered that SHP-1 can make complexes with both EGFR and HER-2, and both phospho-EGFR and phosphor-HER-2 levels in wild-type SHP-1 immunoprecipitates were less than those in phosphatase-inactive SHP-1 (C453S) immunoprecipitates, indicating that EGFR and HER-2 are potential substrates of

  15. Lunasin, a novel seed peptide, sensitizes human breast cancer MDA-MB-231 cells to aspirin-arrested cell cycle and induced apoptosis.

    Science.gov (United States)

    Hsieh, Chia-Chien; Hernández-Ledesma, Blanca; de Lumen, Ben O

    2010-07-30

    Breast cancer is one of the most common tumors in women of Western countries. The high aggressiveness and therapeutic resistance of estrogen-independent breast tumors have motivated the development of new strategies for prevention and/or treatment. Combinations of two or more chemopreventive agents are currently being used to achieve greater inhibitory effects on breast cancer cells. This study reveals that both aspirin and lunasin inhibit, in a dose-dependent manner, human estrogen-independent breast cancer MDA-MB-231 cell proliferation. These compounds arrest the cell cycle in the S- and G1-phases, respectively, acting synergistically to induce apoptosis. To begin elucidating the mechanism(s) of action of these compounds, different molecular targets involved in cell cycle control, apoptosis and signal transduction have been evaluated by real-time polymerase chain reaction (RT-PCR) array. The cell growth inhibitory effect of a lunasin/aspirin combination is achieved, at least partially, by modulating the expression of genes encoding G1 and S-phase regulatory proteins. Lunasin/aspirin therapy exerts its potent pro-apoptotic effect is at least partially achieved through modulating the extrinsic-apoptosis dependent pathway. Synergistic down-regulatory effects were observed for ERBB2, AKT1, PIK3R1, FOS and JUN signaling genes, whose amplification has been reported as being responsible for breast cancer cell growth and resistance to apoptosis. Therefore, our results suggest that a combination of these two compounds is a promising strategy to prevent/treat breast cancer. (c) 2010 Elsevier Ireland Ltd. All rights reserved.

  16. A link prediction approach to cancer drug sensitivity prediction

    OpenAIRE

    Turki, Turki; Wei, Zhi

    2017-01-01

    Background Predicting the response to a drug for cancer disease patients based on genomic information is an important problem in modern clinical oncology. This problem occurs in part because many available drug sensitivity prediction algorithms do not consider better quality cancer cell lines and the adoption of new feature representations; both lead to the accurate prediction of drug responses. By predicting accurate drug responses to cancer, oncologists gain a more complete understanding of...

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

    Science.gov (United States)

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

    2015-03-01

    Inherent or acquired drug resistance is a major contributor to epithelial ovarian cancer (EOC) mortality. Novel drugs or drug combinations that produce EOC cell death or resensitize drug resistant cells to standard chemotherapy may improve patient treatment. After conducting drug tolerability studies for the multikinase inhibitors dorsomorphin (DM) and it is structural analogue LDN-193189 (LDN), these drugs were tested in a mouse intraperitoneal xenograft model of EOC. DM significantly increased survival, whereas LDN showed a trend toward increased survival. In vitro experiments using cisplatin (CP)-resistant EOC cell lines, A2780-cp or SKOV3, we determined that pretreatment or cotreatment with DM or LDN resensitized cells to the killing effect of CP or carboplatin (CB). DM was capable of blocking EOC cell cycle and migration, whereas LDN produced a less pronounced effect on cell cycle and no effect on migration. Subsequent analyses using primary human EOC cell samples or additional established EOC cells lines showed that DM or LDN induced a dose-dependent autophagic or cell death response, respectively. DM induced a characteristic morphological change with the appearance of numerous LC3B-containing acidic vacuoles and an increase in LC3BII levels. This was coincident with a decrease in cell growth and the altered cell cycle consistent with DM-induced cytostasis. By contrast, LDN produced a caspase 3-independent, reactive oxygen species-dependent cell death. Overall, DM and LDN possess drug characteristics suitable for adjuvant agents used to treat chemotherapy-sensitive and -resistant EOC. © 2014 UICC.

  18. Allicin sensitizes hepatocellular cancer cells to anti-tumor activity of 5-fluorouracil through ROS-mediated mitochondrial pathway.

    Science.gov (United States)

    Zou, Xuejing; Liang, Jiyun; Sun, Jingyuan; Hu, Xiaoyun; Lei, Ling; Wu, Dehua; Liu, Li

    2016-08-01

    Drug resistance and hepatic dysfunction are the two major factors that limit the application of chemotherapy for hepatocellular carcinoma (HCC). It has been reported that allicin has the hepatic protective effect and antitumor activity. Hence allicin may be an ideal enhancer to chemotherapy regimen of HCC. In the present study, we demonstrated that allicin enhanced 5-fluorouracil (5-FU) inducing cytotoxicity in HCC cells. In vivo experiment, combined treatment group with allicin (5 mg/kg/d; every two days for 3 weeks) and 5-FU (20 mg/kg/d; 5 consecutive days) showed a dramatic inhibitory effect on the growth of HCC xenograft tumors in nude mice. The co-treatment group showed highly apoptotic level compared with 5-FU treated alone. Cells combined treatment with allicin and 5-FU increased intracellular reactive oxygen species (ROS) level, reduced mitochondrial membrane potential (ΔΨm), activated caspase-3 and PARP, and down-regulated Bcl-2 compared with DMSO, allicin and 5-FU treated alone. Moreover, the increase of activated caspase-3 and PARP was blocked by the ROS inhibitor antioxidant N-acetyl cysteine (NAC). In conclusion, this is the first study to demonstrate that allicin sensitized HCC cells to 5-FU induced apoptosis through ROS-mediated mitochondrial pathway. These results provided evidences for the combination used of allicin and 5-FU as a novel chemotherapy regimen in HCC. Copyright © 2016 The Authors. Production and hosting by Elsevier B.V. All rights reserved.

  19. Allicin sensitizes hepatocellular cancer cells to anti-tumor activity of 5-fluorouracil through ROS-mediated mitochondrial pathway

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    Xuejing Zou

    2016-08-01

    Full Text Available Drug resistance and hepatic dysfunction are the two major factors that limit the application of chemotherapy for hepatocellular carcinoma (HCC. It has been reported that allicin has the hepatic protective effect and antitumor activity. Hence allicin may be an ideal enhancer to chemotherapy regimen of HCC. In the present study, we demonstrated that allicin enhanced 5-fluorouracil (5-FU inducing cytotoxicity in HCC cells. In vivo experiment, combined treatment group with allicin (5 mg/kg/d; every two days for 3 weeks and 5-FU (20 mg/kg/d; 5 consecutive days showed a dramatic inhibitory effect on the growth of HCC xenograft tumors in nude mice. The co-treatment group showed highly apoptotic level compared with 5-FU treated alone. Cells combined treatment with allicin and 5-FU increased intracellular reactive oxygen species (ROS level, reduced mitochondrial membrane potential (ΔΨm, activated caspase-3 and PARP, and down-regulated Bcl-2 compared with DMSO, allicin and 5-FU treated alone. Moreover, the increase of activated caspase-3 and PARP was blocked by the ROS inhibitor antioxidant N-acetyl cysteine (NAC. In conclusion, this is the first study to demonstrate that allicin sensitized HCC cells to 5-FU induced apoptosis through ROS-mediated mitochondrial pathway. These results provided evidences for the combination used of allicin and 5-FU as a novel chemotherapy regimen in HCC.

  20. 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

  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)

    Grimm, Martin; Cetindis, Marcel; Lehmann, Max; Biegner, Thorsten; Munz, Adelheid; Teriete, Peter; Kraut, Wiebke; Reinert, Siegmar

    2014-07-21

    Tumor metabolism is a crucial factor for the carcinogenesis of oral squamous cell carcinoma (OSCC). 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. 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). 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.

  2. Cinnamaldehyde derivative (CB-PIC) sensitizes chemo-resistant cancer cells to drug-induced apoptosis via suppression of MDR1 and its upstream STAT3 and AKT signalling.

    Science.gov (United States)

    Yun, Miyong; Lee, Duckgue; Park, Moon-Nyeo; Kim, Eun-Ok; Sohn, Eun Jung; Kwon, Byung-Mog; Kim, Sung-Hoon

    2015-01-01

    Our group reported that cinnamaldehyde derivative, (E)-4-((2-(3-oxopop-1-enyl)phenoxy)methyl)pyridinium malonic acid (CB-PIC) induced apoptosis in hypoxic SW620 colorectal cancer cells via activation of AMP-activated protein kinase (AMPK) and extracellular signal regulated kinase (ERK). Herein, sensitizing effect of CB-PIC was investigated in resistant cancer cells such as paclitaxel (PT) resistant lung cancer cells (H460/PT), and Adriamycin (Adr) resistant breast cancer (MCF7/Adr) and colon cancer (HCT15/cos) cells. Various drug resistant cell lines were treated with CB-PIC, and the signalling pathway and functional assay were explored by Western blot, Rhodamine assay, FACS, RT-PCR and MTT assay. We found that CB-PIC effectively exerted cytotoxicity, increased sub G1 population and the cleaved form of poly (ADP-ribose) polymerase (PARP) and caspase 9 in drug resistant cancer cells. Furthermore, CB-PIC sensitized resistant cancer cells to adriamycin via downregulation of survival proteins such as survivin, Bcl-xL and Bcl-2, along with MDR1 suppression leading to accumulation of drug in the intracellular region. Of note, CB-PIC transcriptionally decreased MDR1 expression via suppression of STAT3 and AKT signalling in three resistant cancer cells with highly expressed P-glycoprotein. Nonetheless, CB-PIC did not affect transport activity of P-glycoprotein in a short time efflux assay, while epigallocatechin gallate (EGCG) accumulated Rhodamine 123 into intracellular region of cell by direct inhibition of MDR1 transport activity. These data demonstrate that CB-PIC suppresses the P-glycoprotein expression through inhibition of STAT3 and AKT signalling to overcome drug resistance in chemo-resistant cancer cells as a potent chemotherapeutic sensitizer. © 2015 S. Karger AG, Basel.

  3. Down-regulation of human complement factor H sensitizes non-small cell lung cancer cells to complement attack and reduces in vivo tumor growth.

    Science.gov (United States)

    Ajona, Daniel; Hsu, Yi-Fan; Corrales, Leticia; Montuenga, Luis M; Pio, Ruben

    2007-05-01

    Malignant cells are often resistant to complement activation through the enhanced expression of complement inhibitors. In this work, we examined the protective role of factor H, CD46, CD55, and CD59 in two non-small cell lung cancer cell lines, H1264 and A549, upon activation of the classical pathway of complement. Complement was activated with polyclonal Abs raised against each cell line. After blocking factor H activity with a neutralizing Ab, C3 deposition and C5a release were more efficient. Besides, a combined inhibition of factor H and CD59 significantly increased complement-mediated lysis. CD46 and CD55 did not show any effect in the control of complement activation. Factor H expression was knockdown on A549 cells using small interfering RNA. In vivo growth of factor H-deficient cells in athymic mice was significantly reduced. C3 immunocytochemistry on explanted xenografts showed an enhanced activation of complement in these cells. Besides, when mice were depleted of complement with cobra venom factor, growth was recovered, providing further evidence that complement was important in the reduction of in vivo growth. In conclusion, we show that expression of the complement inhibitor factor H by lung cancer cells can prevent complement activation and improve tumor development in vivo. This may have important consequences in the efficiency of complement-mediated immunotherapies.

  4. 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

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

    Directory of Open Access Journals (Sweden)

    Rosa Lauretta

    2016-01-01

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

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

    Science.gov (United States)

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

    2016-01-01

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

  7. Targeting NF-kappa B Signaling by Artesunate Restores Sensitivity of Castrate-Resistant Prostate Cancer Cells to Antiandrogens

    Directory of Open Access Journals (Sweden)

    Jessica J. Nunes

    2017-04-01

    Full Text Available Androgen deprivation therapy (ADT is the most preferred treatment for men with metastatic prostate cancer (PCa. However, the disease eventually progresses and develops resistance to ADT in majority of the patients, leading to the emergence of metastatic castration-resistant prostate cancer (mCRPC. Here, we assessed artesunate (AS, an artemisinin derivative, for its anticancer properties and ability to alleviate resistance to androgen receptor (AR antagonists. We have shown AS in combination with bicalutamide (Bic attenuates the oncogenic properties of the castrate-resistant (PC3, 22RV1 and androgen-responsive (LNCaP PCa cells. Mechanistically, AS and Bic combination inhibits nuclear factor (NF-κB signaling and decreases AR and/or AR-variant 7 expression via ubiquitin-mediated proteasomal degradation. The combination induces oxidative stress and apoptosis via survivin downregulation and caspase-3 activation, resulting in poly-ADP-ribose polymerase (PARP cleavage. Moreover, preclinical castrate-resistant PC3 xenograft studies in NOD/SCID mice (n =28, seven per group show remarkable tumor regression and significant reduction in lungs and bone metastases upon administering AS (50 mg/kg per day in two divided doses and Bic (50 mg/kg per day via oral gavage. Taken together, we for the first time provide a compelling preclinical rationale that AS could disrupt AR antagonist–mediated resistance observed in mCRPC. The current study also indicates that the therapeutic combination of Food and Drug Administration–approved AS or NF-κB inhibitors and AR antagonists may enhance the clinical efficacy in the treatment of mCRPC patients.

  8. PARP inhibition sensitizes to low dose-rate radiation TMPRSS2-ERG fusion gene-expressing and PTEN-deficient prostate cancer cells.

    Directory of Open Access Journals (Sweden)

    Payel Chatterjee

    Full Text Available Exposure to genotoxic agents, such as irradiation produces DNA damage, the toxicity of which is augmented when the DNA repair is impaired. Poly (ADP-ribose polymerase (PARP inhibitors were found to be "synthetic lethal" in cells deficient in BRCA1 and BRCA2 that impair homologous recombination. However, since many tumors, including prostate cancer (PCa rarely have on such mutations, there is considerable interest in finding alternative determinants of PARP inhibitor sensitivity. We evaluated the effectiveness of radiation in combination with the PARP inhibitor, rucaparib in PCa cells. The combination index for clonogenic survival following radiation and rucaparib treatments revealed synergistic interactions in a panel of PCa cell lines, being strongest for LNCaP and VCaP cells that express ETS gene fusion proteins. These findings correlated with synergistic interactions for senescence activation, as indicated by β--galactosidase staining. Absence of PTEN and presence of ETS gene fusion thus facilitated activation of senescence, which contributed to decreased clonogenic survival. Increased radiosensitivity in the presence of rucaparib was associated with persistent DNA breaks, as determined by χ-H2AX, p53BP1, and Rad51 foci. VCaP cells, which harbor the TMPRSS2-ERG gene fusion and PC3 cells that stably express a similar construct (fusion III showed enhanced sensitivity towards rucaparib, which, in turn, increased the radiation response to a similar extent as the DNA-PKcs inhibitor NU7441. Rucaparib radiosensitized PCa cells, with a clear benefit of low dose-rate radiation (LDR administered over a longer period of time that caused enhanced DNA damage. LDR mimicking brachytherapy, which is used successfully in the clinic, was most effective when combined with rucaparib by inducing persistent DNA damage and senescence, leading to decreased clonogenic survival. This combination was most effective in the presence of the TMPRSS2-ERG and in the

  9. Lung cancer - small cell

    Science.gov (United States)

    ... carcinoma Small cell carcinoma Squamous cell carcinoma Secondhand smoke and lung cancer Normal lungs and alveoli Respiratory system Smoking hazards Bronchoscope References Horn L, Eisenberg R, ...

  10. 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 exposure ...

  11. Stepwise targeted drug delivery to liver cancer cells for enhanced therapeutic efficacy by galactose-grafted, ultra-pH-sensitive micelles.

    Science.gov (United States)

    Yan, Guoqing; Wang, Jun; Hu, Liefeng; Wang, Xin; Yang, Guanqing; Fu, Shengxiang; Cheng, Xu; Zhang, Panpan; Tang, Rupei

    2017-03-15

    To promote drug accumulation and cell-killing ability at tumor tissue, we have prepared a stepwise targeted drug delivery system that can remain stealthy and long-circulating in the blood vessels, improve drug retention at extracellular stimuli, enhance cellular uptake through special targeting ligands, and then achieve rapid drug release to improve toxicity to tumor cells at intracellular stimuli. Herein, galactose-grafted, ultra-pH-sensitive drug carriers (POEAd-g-LA-DOX micelles), which could respond to both extracellular and intracellular pH, and combine with galactose-receptors in cell membrane, were constructed by a facile method, therefore achieving: (i) remaining stable at pH 7.4; (ii) responding to tumoral extracellular pH following gradually larger nanoparticles (NPs); (iii) conjugating receptors in the cell membrane of liver cancer through surface galactose-ligands of micelles; (iv) being sensitive to tumoral intracellular pH following further swelling for rapid drug release. In vitro cytotoxicity and cellular uptake measurement showed that POEAd-g-LA20-DOX micelle was more easily internalized and more toxic effect on tumor cells than free DOX. Moreover, in vivo biodistribution and tumor inhibition examinations demonstrated that POEAd-g-LA20-DOX formulation had more superior efficacy to significantly enhance drug accumulation in tumor, and then restrain tumor growth while decreasing drug concentration in heart. Chemotherapeutic efficacy is limited by poor tumor selectivity, which also causes severe toxicity in normal tissues and organs, although many targeted drug delivery systems have been developed by passive targeting strategies or active targeting strategies with specific targeting ligands in recent years. Herein, galactose-grafted, ultra-pH-sensitive, ortho ester-based drug carriers, which can respond to both extracellular and intracellular pH, and target to galactose-receptors in cell membrane, have been successfully constructed by facile method

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

    DEFF Research Database (Denmark)

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

    2009-01-01

    -glycoprotein in cancer cells. In this study, we have investigated the effect of chlorpromazine on tamoxifen response of human breast cancer cells. We found that chlorpromazine worked synergistically together with tamoxifen with respect to reduction of cell growth and metabolic activity, both in the antiestrogen...

  13. 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...... and GLC 19 on recurrence after radiotherapy. TGF beta was detected by ELISA and TGF beta receptors by chemical crosslinking to radiolabelled TGF beta 1. Furthermore, TGF beta and TGF beta receptor mRNAs were detected by northern blot analysis. Expression of type II TGF beta receptor mRNA and protein...

  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

    2017-01-01

    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. PMID:28423356

  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. 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

    of pluripotency genes and simultaneous upregulation of the cell cycle regulators p21, p27, p53, p73 and FOXO1, while no significant effects were found in TCam-2 and 2102Ep cell lines (derived from seminoma and embryonal carcinoma, respectively). Anti-tumor effects of cholecalciferol, 1,25(OH)(2)D(3....... Future studies are needed to investigate potential beneficial effects of vitamin D with lower cisplatin doses, and to determine whether 1,25(OH)(2)D(3) may increase cisplatin sensitivity in chemotherapy-resistant TGCTs. This article is part of a Special Issue entitled 'Vitamin D Workshop'....

  17. Sensitization of Prostate Cancer Cells to Androgen Deprivation and Radiation Via Manipulation of the MDM2 Pathway

    Science.gov (United States)

    2006-04-01

    of Pathology, Fox Chase Cancer Center, Philadelphia, Pennsylvania. 4 Department of Pathology, Latter-Day Saints Hospi- tal, Intermountain Health Care... Saints Hos- pital, Salt Lake City, Utah. 7 Department of Radiation Oncology, University of California, Los Angeles, California. 8 Department of...Cancer Center, Houston, TX; §Department of Pathology, Baylor College of Medicine, Houston, TX Purpose: E2F-1 is a transcription factor that enhances the

  18. Growth Suppression and Therapy Sensitization of Breast Cancer

    Science.gov (United States)

    2001-07-01

    an independent eucaryotic origin of replication (EBV origin). We prepared a pCEP4 vector encoding wild-type p53 (pCEPp53), transduced T47D cells ...activity in tumor cells sensitizes them to a variety of DNA damaging treatments, including doxorubicin, a standard breast cancer therapeutic. An...important determinant of p53-mediated apoptosis is the level of endogenous DNA damage, and this is increased by treatment of cells with inhibitors of DNA

  19. CCN5/WISP-2 restores ER-∝ in normal and neoplastic breast cells and sensitizes triple negative breast cancer cells to tamoxifen.

    Science.gov (United States)

    Sarkar, S; Ghosh, A; Banerjee, S; Maity, G; Das, A; Larson, M A; Gupta, V; Haque, I; Tawfik, O; Banerjee, S K

    2017-05-22

    CCN5/WISP-2 is an anti-invasive molecule and prevents breast cancer (BC) progression. However, it is not well understood how CCN5 prevents invasive phenotypes of BC cells. CCN5 protein expression is detected in estrogen receptor-α (ER-α) -positive normal breast epithelial cells as well as BC cells, which are weakly invasive and rarely metastasize depending on the functional status of ER-α. A unique molecular relation between CCN5 and ER-α has been established as the components of the same signaling pathway that coordinate some essential signals associated with the proliferation as well as delaying the disease progression from a non-invasive to invasive phenotypes. Given the importance of this connection, we determined the role of CCN5 in regulation of ER-α in different cellular settings and their functional relationship. In a genetically engineered mouse model, induced expression of CCN5 in the mammary ductal epithelial cells by doxycycline promotes ER-α expression. Similarly, CCN5 regulates ER-α expression and activity in normal and neoplastic breast cells, as documented in various in vitro settings such as mouse mammary gland culture, human mammary epithelial cell and different BC cell cultures in the presence or absence of human recombinant CCN5 (hrCCN5) protein. Mechanistically, at least in the BC cells, CCN5 is sufficient to induce ER-α expression at the transcription level via interacting with integrins-α6β1 and suppressing Akt followed by activation of FOXO3a. Moreover, in vitro and in vivo functional assays indicate that CCN5 treatment promotes response to tamoxifen in triple-negative BC (TNBC) cells possibly via restoring ER-α. Collectively, these studies implicates that the combination treatments of CCN5 (via activation of CCN5 or hrCCN5 treatment) and tamoxifen as potential therapies for TNBC.

  20. Highly Eribulin-resistant KBV20C Oral Cancer Cells Can Be Sensitized by Co-treatment with the Third-generation P-Glycoprotein Inhibitor, Elacridar, at a Low Dose.

    Science.gov (United States)

    Park, Yujin; Son, Ji-Yeon; Lee, Byung-Mu; Kim, Hyung Sik; Yoon, Sungpil

    2017-08-01

    Eribulin mesylate, also called Halaven® (HAL), was recently developed as a microtubule-targeting drug and is used in the clinic for resistant or metastatic cancer. Previously, we showed that P-glycoprotein (P-gp)-overexpressing KBV20C oral cancer cells are highly resistant to HAL compared to sensitive KB cells. This qualitative study was designed to identify specific P-gp inhibitors that increase the sensitivity of highly resistant cancer cells to HAL. In order to identify functional P-gp inhibitors, HAL-treated KBV20C cells were co-treated with P-gp inhibitors, verapamil, elacridar, cyclosporine A, mitotane, piperine, fumagillin, curcumin, indomethacin, probenecid, sulindac, tesmilifene, and C-4. We then evaluated which P-gp inhibitors required a low dose to sensitize KBV20C cells to HAL. We also determined whether a low dose of a P-gp inhibitor could inhibit P-gp efflux pumping. We found that cyclosporine A sensitized HAL-treated KBV20C cells at a low dose, whereas verapamil, another first-generation P-gp inhibitor, required a dose that was nearly 10-fold higher. We also found that the natural products, piperine and mitotane, sensitized KBV20C cells to HAL co-treatment. Interestingly, we found that elacridar, a third-generation P-gp inhibitor, sensitized HAL-treated cells at a low dose. Elacridar required approximately a 500-fold lower dose than that of verapamil to exert a similar effect. All inhibitors showed P-gp inhibitory activity that correlated with sensitivity to HAL. These results suggest that highly HAL-resistant cancer cells can be sensitized with cyclosporine A or elacridar, specific P-gp inhibitors that exert their effects at a low dose. These findings provide important information regarding the sensitization of highly HAL-resistant cells with selective P-gp inhibitors and indicate that elacridar may be used to treat such highly HAL-resistant cancer cells. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios

  1. Association of thymidylate synthase gene 3'-untranslated region polymorphism with sensitivity of non-small cell lung cancer to pemetrexed treatment: TS gene polymorphism and pemetrexed sensitivity in NSCLC.

    Science.gov (United States)

    Wang, Xia; Wang, Yadi; Wang, Yue; Cheng, Jian; Wang, Yanyun; Ha, Minwen

    2013-01-25

    Thymidylate synthase (TS) is a key enzyme responsible for DNA synthesis and repair. Altered expression of TS protein or TS gene polymorphisms has been associated with cancer progression and treatment response. This study investigated the expressions of TS and its gene SNPs in non-small cell lung cancer (NSCLC), and then its association with sensitivity to pemetrexed treatment. Immunohistochemistry and qRT-PCR were performed on 160 resected NSCLC specimens and corresponding normal tissues to assess the expressions of TS protein and TS mRNA, and for associations with clinicopathological data. Blood samples of 106 lung adenocarcinoma patients were examined for polymorphisms of the TS gene 3'-UTR 1494del 6 bp, which was then investigated for associations with responses of the patients to pemetrexed treatment and survival. Expression of both TS protein and its mRNA was elevated in NSCLC tissues compared with matched normal tissues, and significantly higher in lung squamous cell carcinoma than in lung adenocarcinoma. TS expression was associated with poor tumor differentiation. Furthermore, the genotyping data showed that 56% of lung adenocarcinoma patients had the TS gene 3'-UTR 1494 bp (-6 bp/-6 bp) genotype and the rest had TS gene 3'-UTR 1494 bp (-6 bp/+6 bp). There was no TS 3'-UTR 1494 bp (+6 bp/+6 bp) genotype in any patients. Statistical analysis revealed that gender, tumor stage, and TS 3'-UTR 1494del 6 bp polymorphism were significant prognostic factors after short-term pemetrexed treatment. Log-rank analysis revealed that patients with the (-6 bp/-6 bp) genotype had significantly better progression-free and overall survival than patients with (-6 bp/+6 bp). This study showed that TS protein is highly expressed in NSCLC and that polymorphisms of TS 3'-UTR 1494del 6 bp are associated with sensitivity of lung adenocarcinoma patients to pemetrexed treatment. This suggests that TS gene polymorphisms should be further evaluated as prognostic markers for personalized

  2. pH-Sensitive Coiled-Coil Peptide-Cross-Linked Hyaluronic Acid Nanogels: Synthesis and Targeted Intracellular Protein Delivery to CD44 Positive Cancer Cells.

    Science.gov (United States)

    Ding, Lingling; Jiang, Yu; Zhang, Jian; Klok, Harm-Anton; Zhong, Zhiyuan

    2018-02-12

    The clinical translation of protein drugs that act intracellularly is limited by the absence of safe and efficient intracellular protein delivery vehicles. Here, pH-sensitive coiled-coil peptide-cross-linked hyaluronic acid nanogels (HA-cNGs) were designed and investigated for targeted intracellular protein delivery to CD44 overexpressing MCF-7 breast cancer cells. HA-cNGs were obtained with a small size of 176 nm from an equivalent mixture of hyaluronic acid conjugates with GY(EIAALEK) 3 GC (E3) and GY(KIAALKE) 3 GC (K3) peptides, respectively, at pH 7.4 by nanoprecipitation. Circular dichroism (CD) proved the formation of coiled-coil structures between E3 and K3 peptides at pH 7.4 while fast uncoiling at pH 5.0. HA-cNGs showed facile loading of cytochrome C (CC) and greatly accelerated CC release under mild acidic conditions (18.4%, 76.8%, and 91.4% protein release in 24 h at pH 7.4, 6.0, and 5.0, respectively). Confocal microscopy and flow cytometry displayed efficient internalization of CC-loaded HA-cNGs and effective endosomal escape of CC in MCF-7 cancer cells. Remarkably, HA-cNGs loaded with saporin, a ribosome inactivating protein, exhibited significantly enhanced apoptotic activity to MCF-7 cells with a low IC 50 of 12.2 nM. These coiled-coil peptide-cross-linked hyaluronic acid nanogels have appeared as a simple and multifunctional platform for efficient intracellular protein delivery.

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

    Science.gov (United States)

    2012-10-01

    GMNN) or synergistically ( CCNA2 , CDC20, CCNB2, Survivin/BIRC5, GADD45G, E2F1, ITPR1, BRCA1). Genes that are known to modulate the cell cycle ( CCNA2 ...changes in the mRNA levels of cell cycle regulators. CCNA2 , GMNN, CDC20 and CCNB2 transcript levels were measured over a 72 h time course in LNCaP cells ...been rigorously evaluated (48). The cells express wild type AR and are positive for PSA, PCA3, PSCA (prostate stem cell antigen), PSMA (prostate

  4. Liver Cancer Stem Cells

    OpenAIRE

    Sameh Mikhail; Aiwu Ruth He

    2011-01-01

    Hepatocellular carcinoma is the most common primary malignancy of the liver in adults. It is also the fifth most common solid cancer worldwide and the third leading cause of cancer-related death. Recent research supports that liver cancer is a disease of adult stem cells. From the models of experimental hepatocarcinogenesis, there may be at least three distinct cell lineages with progenitor properties susceptible to neoplastic transformation. Identification of specific cell surface markers fo...

  5. XPC gene intron 11 C/A polymorphism is a predictive biomarker for the sensitivity to NP chemotherapy in patients with non-small cell lung cancer.

    Science.gov (United States)

    Zhu, Li-Bo; Xu, Qian; Hong, Cheng-Yu; Yue, Zheng; Zhang, Ye; Ye, Hui-Nan; Yuan, Yuan

    2010-08-01

    The fact that intron single nucleotide polymorphisms could regulate gene expression or even alter gene expression levels has been the focus of attention. To study the relationship between the intron 11 C/A single nucleotide polymorphism of XPC gene and the efficacy of vinorelbine and cisplatin (NP) chemotherapy, 164 patients with non-small cell lung cancer (NSCLC) taking NP chemotherapy drugs were evaluated according to the efficacy of the treatment. We used polymerase chain reaction restriction fragment length polymorphism to examine the C/A polymorphism in the XPC gene intron 11 of the DNA samples extracted from peripheral blood. It was found that the frequency of patients in the effective group with C/C+C/A genotype (37.6%) had significant difference to chemotherapy than that of patients with A/A homozygotes (27.7%) in the same group (P=0.043, odds ratio=2.366, 95% confidence interval=1.026-5.457). Therefore, NSCLC patients with the C/C+C/A genotype are more sensitive to NP treatment than those with the A/A genotype. The XPC gene intron 11 C/A polymorphism may be a predictive biomarker for sensitivity to NP chemotherapy in patients with NSCLC.

  6. Cancer stem cell metabolism

    National Research Council Canada - National Science Library

    Peiris-Pagès, Maria; Martinez-Outschoorn, Ubaldo E; Pestell, Richard G; Sotgia, Federica; Lisanti, Michael P

    2016-01-01

    .... Cancer stem cells also seem to adapt their metabolism to microenvironmental changes by conveniently shifting energy production from one pathway to another, or by acquiring intermediate metabolic phenotypes...

  7. Drug screening and grouping by sensitivity with a panel of primary cultured cancer spheroids derived from endometrial cancer.

    Science.gov (United States)

    Kiyohara, Yumiko; Yoshino, Kiyoshi; Kubota, Satoshi; Okuyama, Hiroaki; Endo, Hiroko; Ueda, Yutaka; Kimura, Toshihiro; Kimura, Tadashi; Kamiura, Shoji; Inoue, Masahiro

    2016-04-01

    Several molecular targeting drugs are being evaluated for endometrial cancer; selecting patients whose cancers are sensitive to these agents is of paramount importance. Previously, we developed the cancer tissue-originated spheroid method for primary cancer cells taken from patients' tumors as well as patient-derived xenografts. In this study, we successfully prepared and cultured cancer tissue-originated spheroids from endometrial cancers. Characteristics of the original tumors were well retained in cancer tissue-originated spheroids including morphology and expression of p53 or neuroendocrine markers. We screened 79 molecular targeting drugs using two cancer tissue-originated spheroid lines derived from endometrioid adenocarcinoma grade 3 and serous adenocarcinoma. Among several hits, we focused on everolimus, a mammalian target of rapamycin complex 1 inhibitor, and YM155, a survivin inhibitor. When sensitivity to everolimus or YM155 was assessed in 12 or 11 cancer tissue-originated spheroids, respectively, from different endometrial cancer patients, the sensitivity varied substantially. The cancer tissue-originated spheroids sensitive to everolimus showed remarkable suppression of proliferation. The phosphorylation status of the mammalian target of rapamycin complex 1 downstream molecules before and after everolimus treatment did not predict the effect of the drug. In contrast, the cancer tissue-originated spheroids sensitive to YM155 showed remarkable cell death. The effect of YM155 was also confirmed in vivo. The histological type correlated with YM155 sensitivity; non-endometrioid adenocarcinomas were sensitive and endometrioid adenocarcinomas were resistant. Non-canonical autophagic cell death was the most likely cause of cell death in a sensitive cancer tissue-originated spheroid. Thus, sensitivity assays using cancer tissue-originated spheroids from endometrial cancers may be useful for screening drugs and finding biomarkers. © 2016 The Authors. Cancer

  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. 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.

  10. 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

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    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

  11. Adaphostin toxicity in a sensitive non-small cell lung cancer model is mediated through Nrf2 signaling and heme oxygenase 1

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    Monks Anne

    2010-07-01

    Full Text Available Abstract Background Preclinical toxicity of adaphostin has been related to oxidative stress. This study investigated the regulatory mechanism underlying adaphostin induction of heme oxygenase 1 (HMOX1 which plays a significant role in modulation of drug-induced toxicity in the non-small cell lung cancer cell line model, NCI-H522. Methods The transcriptional response of NCI-H522 to adaphostin prominently involved oxidative stress genes, particularly HMOX1. Reactive oxygen species (ROS involvement was additionally established by generation of ROS prior to modulation of adaphostin-toxicity with antioxidants. To identify up-stream regulatory elements of HMOX1, immunofluorescence was used to evaluate nuclear translocation of the transcription factor, NF-E2-related factor 2 (Nrf2, in the presence of adaphostin. The PI3-kinase inhibitor, wortmannin, was employed as a pharmacological inhibitor of this process. Results Generation of ROS provided a substantial foundation for the sensitivity of NCI-H522 to adaphostin. However, in contrast to leukemia cell lines, transcriptional response to oxidative stress was associated with induction of HMOX1, which was dependent on nuclear translocation of the transcription factor, Nrf2. Pretreatment of cells with wortmannin inhibited translocation of Nrf2 and induction of HMOX1. Wortmannin pretreatment was also able to diminish adaphostin induction of HMOX1, and as a consequence, enhance the toxicity of adaphostin to NCI-H522. Conclusions Adaphostin-induced oxidative stress in NCI-H522 was mediated through nuclear translocation of Nrf2 leading to upregulation of HMOX1. Inhibition of Nrf2 translocation by wortmannin inhibited this cytoprotective response, and enhanced the toxicity of adaphostin, suggesting that inhibitors of the PI3K pathway, such as wortmannin, might augment the antiproliferative effects of adaphostin in solid tumors that depend on the Nrf2/ARE pathway for protection against oxidative stress.

  12. Disruption of the ER-α36-EGFR/HER2 Positive Regulatory Loops Restores Tamoxifen Sensitivity in Tamoxifen Resistance Breast Cancer Cells

    OpenAIRE

    Yin, Li; Zhang, Xin-Tian; Bian, Xiu-Wu; Guo, Yu-Ming; Wang, Zhao-Yi

    2014-01-01

    Tamoxifen provided a successful treatment for ER-positive breast cancer for many years. However, most breast tumors develop tamoxifen resistance and are eventually refractory to tamoxifen therapy. The molecular mechanisms underlying development of tamoxifen resistance have not been well established. Recently, we reported that breast cancer cells with high levels of ER-α36, a variant of ER-α, were resistant to tamoxifen and knockdown of ER-α36 expression in tamoxifen resistant cells with the s...

  13. Basal cell cancer (image)

    Science.gov (United States)

    ... biopsy is needed to prove the diagnosis of basal cell carcinoma. Treatment varies depending on the size, depth, and location of the cancer. Early treatment by a dermatologist may result in a cure ... is required to watch for new sites of basal cell cancer.

  14. Effect of culture conditions on androgen sensitivity of the human prostatic cancer cell line LNCaP

    NARCIS (Netherlands)

    E.G. Langeler (E.); C.J. van Uffelen; M.A. Blankenstein (Marinus); G.J. van Steenbrugge (Gert Jan); E. Mulder (Eppo)

    1993-01-01

    textabstractSeveral effects of androgens on LNCaP-FGC prostate tumor cells showed a biphasic pattern. Stimulation of growth and inhibition of secretion of prostatic acid phosphatase (PAP) was observed at low androgen concentrations (below 1 nM of the synthetic androgen R1881), and inhibition of

  15. Prostate cancer stem cells.

    Science.gov (United States)

    Tu, Shi-Ming; Lin, Sue-Hwa

    2012-06-01

    Stem cells have long been implicated in prostate gland formation. The prostate undergoes regression after androgen deprivation and regeneration after testosterone replacement. Regenerative studies suggest that these cells are found in the proximal ducts and basal layer of the prostate. Many characteristics of prostate cancer indicate that it originates from stem cells. For example, the putative androgen receptor-negative (AR(-)) status of prostate stem cells renders them inherently insensitive to androgen blockade therapy. The androgen-regulated gene fusion TMPRSS2-ERG could be used to clarify both the cells of origin and the evolution of prostate cancer cells. In this review, we show that the hypothesis that distinct subtypes of cancer result from abnormalities within specific cell types-the stem cell theory of cancer-may instigate a major paradigm shift in cancer research and therapy. Ultimately, the stem cell theory of cancers will affect how we practice clinical oncology: our diagnosis, monitoring, and therapy of prostate and other cancers. Copyright © 2012 Elsevier Inc. All rights reserved.

  16. 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

    Science.gov (United States)

    2012-01-01

    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 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 against oxidative stress mediated by ascorbic acid induced hydrogen peroxide production. The antioxidative enzyme catalase is important to protect cancer cells against cytotoxic hydrogen peroxide

  17. 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.

  18. 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.

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

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    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.

  20. Response to mTOR inhibition: activity of eIF4E predicts sensitivity in cell lines and acquired changes in eIF4E regulation in breast cancer

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    Bartlett John MS

    2011-02-01

    Full Text Available Abstract Background Inhibitors of the kinase mTOR, such as rapamycin and everolimus, have been used as cancer therapeutics with limited success since some tumours are resistant. Efforts to establish predictive markers to allow selection of patients with tumours likely to respond have centred on determining phosphorylation states of mTOR or its targets 4E-BP1 and S6K in cancer cells. In an alternative approach we estimated eIF4E activity, a key effector of mTOR function, and tested the hypothesis that eIF4E activity predicts sensitivity to mTOR inhibition in cell lines and in breast tumours. Results We found a greater than three fold difference in sensitivity of representative colon, lung and breast cell lines to rapamycin. Using an assay to quantify influences of eIF4E on the translational efficiency specified by structured 5'UTRs, we showed that this estimate of eIF4E activity was a significant predictor of rapamycin sensitivity, with higher eIF4E activities indicative of enhanced sensitivity. Surprisingly, non-transformed cell lines were not less sensitive to rapamycin and did not have lower eIF4E activities than cancer lines, suggesting the mTOR/4E-BP1/eIF4E axis is deregulated in these non-transformed cells. In the context of clinical breast cancers, we estimated eIF4E activity by analysing expression of eIF4E and its functional regulators within tumour cells and combining these scores to reflect inhibitory and activating influences on eIF4E. Estimates of eIF4E activity in cancer biopsies taken at diagnosis did not predict sensitivity to 11-14 days of pre-operative everolimus treatment, as assessed by change in tumour cell proliferation from diagnosis to surgical excision. However, higher pre-treatment eIF4E activity was significantly associated with dramatic post-treatment changes in expression of eIF4E and 4E-binding proteins, suggesting that eIF4E is further deregulated in these tumours in response to mTOR inhibition. Conclusions

  1. Association of thymidylate synthase gene 3'-untranslated region polymorphism with sensitivity of non-small cell lung cancer to pemetrexed treatment: TS gene polymorphism and pemetrexed sensitivity in NSCLC

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    Wang Xia

    2013-01-01

    Full Text Available Abstract Background Thymidylate synthase (TS is a key enzyme responsible for DNA synthesis and repair. Altered expression of TS protein or TS gene polymorphisms has been associated with cancer progression and treatment response. This study investigated the expressions of TS and its gene SNPs in non-small cell lung cancer (NSCLC, and then its association with sensitivity to pemetrexed treatment. Immunohistochemistry and qRT-PCR were performed on 160 resected NSCLC specimens and corresponding normal tissues to assess the expressions of TS protein and TS mRNA, and for associations with clinicopathological data. Blood samples of 106 lung adenocarcinoma patients were examined for polymorphisms of the TS gene 3’-UTR 1494del 6 bp, which was then investigated for associations with responses of the patients to pemetrexed treatment and survival. Results Expression of both TS protein and its mRNA was elevated in NSCLC tissues compared with matched normal tissues, and significantly higher in lung squamous cell carcinoma than in lung adenocarcinoma. TS expression was associated with poor tumor differentiation. Furthermore, the genotyping data showed that 56% of lung adenocarcinoma patients had the TS gene 3’-UTR 1494 bp (−6 bp/-6 bp genotype and the rest had TS gene 3’-UTR 1494 bp (−6 bp/+6 bp. There was no TS 3’-UTR 1494 bp (+6 bp/+6 bp genotype in any patients. Statistical analysis revealed that gender, tumor stage, and TS 3’-UTR 1494del 6 bp polymorphism were significant prognostic factors after short-term pemetrexed treatment. Log-rank analysis revealed that patients with the (−6 bp/-6 bp genotype had significantly better progression-free and overall survival than patients with (−6 bp/+6 bp. Conclusions This study showed that TS protein is highly expressed in NSCLC and that polymorphisms of TS 3’-UTR 1494del 6 bp are associated with sensitivity of lung adenocarcinoma patients to pemetrexed treatment. This suggests that TS gene

  2. Application of ZnO/graphene and S6 aptamers for sensitive photoelectrochemical detection of SK-BR-3 breast cancer cells based on a disposable indium tin oxide device.

    Science.gov (United States)

    Liu, Fang; Zhang, Yan; Yu, Jinghua; Wang, Shaowei; Ge, Shenguang; Song, Xianrang

    2014-01-15

    ZnO/graphene (ZnO/G) composite and S6 aptamer were employed to sensitive photoelectrochemical (PEC) strategy for the specific detection of SK-BR-3 cancer cells based on a portable indium tin oxide microdevice. ZnO/G composite was synthesized using a facile ultrasonic method, and then applied to improve the PEC performance due to the unique hollow structure of ZnO naospheres and the superior properties of graphene. Subsequently, S6 aptamer was applied to this specific detection of SK-BR-3 cancer cells. And the concentration of SK-BR-3 cells was measured with a low detection limit of 58 cells mL(-1) and a wide linear range of 1×10(2)-1×10(6) cells mL(-1), through the decrease in photocurrent intensity resulting from the increase in steric hindrances when specifically recognized with S6 aptamers. Excellent discrimination against target and analogous cells was demonstrated, indicating the high selectivity of the proposed cell sensor. Our work also demonstrated a sensitive, stable and low cytotoxicity approach for early and accurate detection of cancer cells. © 2013 Elsevier B.V. All rights reserved.

  3. The relevance of using 3D cell cultures, in addition to 2D monolayer cultures, when evaluating breast cancer drug sensitivity and resistance

    Science.gov (United States)

    Breslin, Susan; O'Driscoll, Lorraine

    2016-01-01

    Solid tumours naturally grow in 3D wherein the spatial arrangement of cells affects how they interact with each other. This suggests that 3D cell culture may mimic the natural in vivo setting better than traditional monolayer (2D) cell culture, where cells are grown attached to plastic. Here, using HER2-positive breast cancer cell lines as models (BT474, HCC1954, EFM192A), the effects of culturing cells in 3D using the poly-HEMA method compared to 2D cultures were assessed in terms of cellular viability, response/resistance to anti-cancer drugs, protein expression and enzyme activity. Scanning electron microscopy showed the morphology of cells in 3D to be substantially different to those cultured in 2D. Cell viability in 3D cells was substantially lower than that of cells in 2D cultures, while 3D cultures were more resistant to the effects of HER-targeted (neratinib) and classical chemotherapy (docetaxel) drugs. Expression of proteins involved in cell survival, transporters associated with drug resistance and drug targets were increased in 3D cultures. Finally, activity of drug metabolising enzyme CYP3A4 was substantially increased in 3D compared to 2D cultures. Together this data indicates that the biological information represented by 3D and 2D cell cultures is substantially different i.e. 3D cell cultures demonstrate higher innate resistance to anti-cancer drugs compared to 2D cultures, which may be facilitated by the altered receptor proteins, drug transporters and metabolising enzyme activity. This highlights the importance of considering 3D in addition to 2D culture methods in pre-clinical studies of both newer targeted and more traditional anti-cancer drugs. PMID:27304190

  4. Protons sensitize epithelial cells to mesenchymal transition.

    Science.gov (United States)

    Wang, Minli; Hada, Megumi; Saha, Janapriya; Sridharan, Deepa M; Pluth, Janice M; Cucinotta, Francis A

    2012-01-01

    Proton radiotherapy has gained more favor among oncologists as a treatment option for localized and deep-seated tumors. In addition, protons are a major constituent of the space radiation astronauts receive during space flights. The potential for these exposures to lead to, or enhance cancer risk has not been well studied. Our objective is to study the biological effects of low energy protons on epithelial cells and its propensity to enhance transforming growth factor beta 1 (TGFβ1)-mediated epithelial-mesenchymal transition (EMT), a process occurring during tumor progression and critical for invasion and metastasis. Non-transformed mink lung epithelial cells (Mv1Lu) and hTERT- immortalized human esophageal epithelial cells (EPC) were used in this study. EMT was identified by alterations in cell morphology, EMT-related gene expression changes determined using real-time PCR, and EMT changes in specific cellular markers detected by immunostaining and western blotting. Although TGFβ1 treatment alone is able to induce EMT in both Mv1Lu and EPC cells, low energy protons (5 MeV) at doses as low as 0.1 Gy can enhance TGFβ1 induced EMT. Protons alone can also induce a mild induction of EMT. SD208, a potent TGFβ Receptor 1 (TGFβR1) kinase inhibitor, can efficiently block TGFβ1/Smad signaling and attenuate EMT induction. We suggest a model for EMT after proton irradiation in normal and cancerous tissue based on our results that showed that low and high doses of protons can sensitize normal human epithelial cells to mesenchymal transition, more prominently in the presence of TGFβ1, but also in the absence of TGFβ1.

  5. 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.

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

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    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

  7. Breast cancer stem cells

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    Thomas W Owens

    2013-08-01

    Full Text Available Cancer metastasis, resistance to therapies and disease recurrence are significant hurdles to successful treatment of breast cancer. Identifying mechanisms by which cancer spreads, survives treatment regimes and regenerates more aggressive tumours are critical to improving patient survival. Substantial evidence gathered over the last 10 years suggests that breast cancer progression and recurrence is supported by cancer stem cells (CSCs. Understanding how CSCs form and how they contribute to the pathology of breast cancer will greatly aid the pursuit of novel therapies targeted at eliminating these cells. This review will summarise what is currently known about the origins of breast CSCs, their role in disease progression and ways in which they may be targeted therapeutically.

  8. Inhibition of Aerobic Glycolysis Represses Akt/mTOR/HIF-1α Axis and Restores Tamoxifen Sensitivity in Antiestrogen-Resistant Breast Cancer Cells.

    Science.gov (United States)

    Woo, Yu Mi; Shin, Yubin; Lee, Eun Ji; Lee, Sunyoung; Jeong, Seung Hun; Kong, Hyun Kyung; Park, Eun Young; Kim, Hyoung Kyu; Han, Jin; Chang, Minsun; Park, Jong-Hoon

    2015-01-01

    Tamoxifen resistance is often observed in the majority of estrogen receptor-positive breast cancers and it remains as a serious clinical problem in breast cancer management. Increased aerobic glycolysis has been proposed as one of the mechanisms for acquired resistance to chemotherapeutic agents in breast cancer cells such as adriamycin. Herein, we report that the glycolysis rates in LCC2 and LCC9--tamoxifen-resistant human breast cancer cell lines derived from MCF7--are higher than those in MCF7S, which is the parent MCF7 subline. Inhibition of key glycolytic enzyme such as hexokinase-2 resulted in cell growth retardation at higher degree in LCC2 and LCC9 than that in MCF7S. This implies that increased aerobic glycolysis even under O2-rich conditions, a phenomenon known as the Warburg effect, is closely associated with tamoxifen resistance. We found that HIF-1α is activated via an Akt/mTOR signaling pathway in LCC2 and LCC9 cells without hypoxic condition. Importantly, specific inhibition of hexokinase-2 suppressed the activity of Akt/mTOR/HIF-1α axis in LCC2 and LCC9 cells. In addition, the phosphorylated AMPK which is a negative regulator of mTOR was decreased in LCC2 and LCC9 cells compared to MCF7S. Interestingly, either the inhibition of mTOR activity or increase in AMPK activity induced a reduction in lactate accumulation and cell survival in the LCC2 and LCC9 cells. Taken together, our data provide evidence that development of tamoxifen resistance may be driven by HIF-1α hyperactivation via modulation of Akt/mTOR and/or AMPK signaling pathways. Therefore, we suggest that the HIF-1α hyperactivation is a critical marker of increased aerobic glycolysis in accordance with tamoxifen resistance and thus restoration of aerobic glycolysis may be novel therapeutic target for treatment of tamoxifen-resistant breast cancer.

  9. 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.

  10. A cancer cell-specific fluorescent probe for imaging Cu2 + in living cancer cells

    Science.gov (United States)

    Wang, Chao; Dong, Baoli; Kong, Xiuqi; Song, Xuezhen; Zhang, Nan; Lin, Weiying

    2017-07-01

    Monitoring copper level in cancer cells is important for the further understanding of its roles in the cell proliferation, and also could afford novel copper-based strategy for the cancer therapy. Herein, we have developed a novel cancer cell-specific fluorescent probe for the detecting Cu2 + in living cancer cells. The probe employed biotin as the cancer cell-specific group. Before the treatment of Cu2 +, the probe showed nearly no fluorescence. However, the probe can display strong fluorescence at 581 nm in response to Cu2 +. The probe exhibited excellent sensitivity and high selectivity for Cu2 + over the other relative species. Under the guidance of biotin group, could be successfully used for detecting Cu2 + in living cancer cells. We expect that this design strategy could be further applied for detection of the other important biomolecules in living cancer cells.

  11. Sensitivity of neoplastic cells to senescence unveiled under standard cell culture conditions.

    Science.gov (United States)

    Zieba, Jolanta; Ksiazkiewcz, Magdalena; Janik, Karolina; Banaszczyk, Mateusz; Peciak, Joanna; Piaskowski, Sylwester; Lipinski, Marek; Olczak, Michal; Stoczynska-Fidelus, Ewelina; Rieske, Piotr

    2015-05-01

    Cancer cells are typically defined as infinitely proliferating, whereas normal cells (except stem cells) are considered as being programmed to become senescent. Our data show that this characterization is misleading. Multiplex Ligation-dependent Probe Amplification, TP53 sequencing, real-time polymerase chain reaction (PCR) for MUC1 and SCGB2A2 and immunocytochemistry, together with senescence detection assay and real-time microscopic observations were used to analyze primary neoplastic cells isolated from prostate, breast and colorectal tumors, as well as stable cancer cell lines (MCF7, MDA-MB-468, SW962, SK-MEL28, NCI-H1975 and NCI-H469). In all cases of primary cancer cell cultures, in vitro conditions rapidly revealed senescence in the majority of cells. Two out of six stable cancer cell lines did not exhibit any senescence-associated-β-Galactosidase-positive cells. Interestingly, four cell lines had small sub-populations of senescent cells (single SA-β-Gal-positive cells). Primary neoplastic cells from different types of cancer (prostate, breast, colon cancer) appear to be senescent in vitro. Apparently, cancer cell lines that have been used for many years in drug-testing analyses have constantly been misleading researchers in terms of the general sensitivity of cancer cells to senescence. Copyright© 2015 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

  12. Hurthle Cell Cancer

    Science.gov (United States)

    ... breath Hurthle cell cancer Symptoms & causes Diagnosis & treatment Advertisement Mayo Clinic does not endorse companies or products. ... a Job Site Map About This Site Twitter Facebook Google YouTube Pinterest Mayo Clinic is a not- ...

  13. Basal cell skin cancer

    Science.gov (United States)

    Basal cell skin cancer almost never spreads. If it is left untreated, it may spread into surrounding areas and nearby tissues and bone. In these cases, treatment can injure the appearance of the skin.

  14. 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.

  15. Epigallocatechin gallate sensitizes cisplatin-resistant oral cancer CAR cell apoptosis and autophagy through stimulating AKT/STAT3 pathway and suppressing multidrug resistance 1 signaling.

    Science.gov (United States)

    Yuan, Chien-Han; Horng, Chi-Ting; Lee, Chiu-Fang; Chiang, Ni-Na; Tsai, Fuu-Jen; Lu, Chi-Cheng; Chiang, Jo-Hua; Hsu, Yuan-Man; Yang, Jai-Sing; Chen, Fu-An

    2017-03-01

    Epigallocatechin gallate (EGCG) is a green tea polyphenol that presents anticancer activities in multiple cancer cells, but no available report was addressed for the underling molecular mechanism of cytotoxic impacts on drug-resistant oral squamous cell carcinoma cells. In the present study, the inhibitory effects of EGCG were experienced on cisplatin-resistant oral cancer CAR cells. EGCG inhibited cell viability in a time- and concentration-dependent manner by a sulforhodamine B (SRB) assay. EGCG induced CAR cell apoptosis and autophagy by 4',6-diamidino-2-phenylindole (DAPI) dye, acridine orange (AO) staining and green fluorescent protein (GFP)-tagged LC3B assay, respectively. EGCG also significantly enhanced caspase-9 and caspase-3 activities by caspase activity assay. EGCG markedly increased the protein levels of Bax, cleaved caspase-9, cleaved caspase-3, Atg5, Atg7, Atg12, Beclin-1, and LC3B-II, as well as significantly decreased the expression of Bcl-2, phosphorylated AKT (Ser473) and phosphorylation of STAT3 on Tyr705 by western blotting in CAR cells. Importantly, the protein and gene expression of multidrug resistance 1 (MDR1) were dose-dependently inhibited by EGCG. Overall, downregulation of MDR1 levels and alterations of AKT/STAT3 signaling contributed to EGCG-induced apoptosis and autophagy in CAR cells. Based on these results, EGCG has the potential for therapeutic effect on oral cancer and may be useful for long-term oral cancer prevention in the future. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 845-855, 2017. © 2016 Wiley Periodicals, Inc.

  16. Relationship between Expression of β-tubulin-Ⅲ Plus Stathmin in Advanced Non-Small Cell Lung Cancer and its Sensitivity to Venorelbine Chemotherapy

    Directory of Open Access Journals (Sweden)

    Xiaolin PU

    2009-01-01

    Full Text Available Background and objective Vinorelbine plus cisplatin/carboplatin (NP is one of the standard combination chemotherapy regimen for advanced non-small cell lung cancer (NSCLC. The aim of this study is toinvestigate the relationship between expression of Stathmin and β-tubulin-Ⅲ in NSCLC biopsies and sensitivity to Vinorelbine, which would provide a basis of the proper medicine choice for the patients' tailored chemotherapy. Methods Western blot was used to investigate the expression of Stathmin and β-tubulin-Ⅲ protein in the biopsies from stage ⅢB-Ⅳ NSCLC patients. All the cases were divided into 4 groups according to the level of the two proteins, of which L represented both protein expressed lowly, B showed β-tubulin-Ⅲ lowly expressed group, while S showed Stathmin lowly, and H represented both protein highly expressed. At the same time, all the patients accepted NP chemotherapy for 2 or 4 cycles according to the responses to this regimen. The responses rate (RR, media survival time (MST, time to progress (TTP were observed. Results A total of 90 stage ⅢB-Ⅳ NSCLC patients were divided into 4 groups, 22 in L group, 23 in B and S group while 22 in H group respectively. The RR of the groups were 68.2%, 26.1%, 30.4% and 22.7% respectively.There were statistically significant differences between L group and other 3 groups (P <0.05. The MST were 377, 305, 321 and 271 days respectively, and the TTP were 240, 182, 190 and 166 days in the 4 groups. Statistically significant differences between L group and other 3 groups (P <0.05 can be seen in both MST and TTP. Conclusion The expression of β-tubulin-Ⅲ and Stathmin in advanced NSCLC biopsies had relationship with the sensitivity to NP chemotherapyregimen in the patients. Cases with high level of these two proteins would have poor responses to this cytotoxic drug.

  17. 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

  18. Inflammation and cancer stem cells.

    Science.gov (United States)

    Shigdar, Sarah; Li, Yong; Bhattacharya, Santanu; O'Connor, Michael; Pu, Chunwen; Lin, Jia; Wang, Tao; Xiang, Dongxi; Kong, Lingxue; Wei, Ming Q; Zhu, Yimin; Zhou, Shufeng; Duan, Wei

    2014-04-10

    Cancer stem cells are becoming recognised as being responsible for metastasis and treatment resistance. The complex cellular and molecular network that regulates cancer stem cells and the role that inflammation plays in cancer progression are slowly being elucidated. Cytokines, secreted by tumour associated immune cells, activate the necessary pathways required by cancer stem cells to facilitate cancer stem cells progressing through the epithelial-mesenchymal transition and migrating to distant sites. Once in situ, these cancer stem cells can secrete their own attractants, thus providing an environment whereby these cells can continue to propagate the tumour in a secondary niche. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  19. GPX3 promoter methylation predicts platinum sensitivity in colorectal cancer.

    Science.gov (United States)

    Pelosof, Lorraine; Yerram, Sashidhar; Armstrong, Todd; Chu, Nina; Danilova, Ludmila; Yanagisawa, Breann; Hidalgo, Manuel; Azad, Nilofer; Herman, James G

    2017-07-03

    Epigenetic control of gene expression is a major determinant of tumor phenotype and has been found to influence sensitivity to individual chemotherapeutic agents. Glutathione peroxidase 3 (GPX3, plasma glutathione peroxidase) is a key component of cellular antioxidant regulation and its gene has been reported to be methylated in specific tumor types. GPX3 role in oxidative damage has been associated with sensitivity to platinums in other tumors but its importance in colorectal cancer (CRC) has not been determined. We examined the role of GPX3 methylation in colorectal carcinoma in determining sensitivity to platinum drugs using primary tumor specimens, cell lines, knockdown cell lines, and tumor cell line xenografts. We find GPX3 promoter region methylation in approximately one third of CRC samples and GPX3 methylation leads to reduced GPX3 expression and increased oxaliplatin and cisplatin sensitivity. In contrast, in cell lines with high baseline levels of GPX3 expression or with the ability to increase GPX3 expression, platinum resistance is increased. The cisplatin IC50 in GPX3-methylated cell lines is approximately 6-fold lower than that in GPX3-unmethylated lines. Additionally, knockdown cell lines with essentially no GPX3 expression require N-acetylcysteine to survive in culture underscoring the importance of GPX3 in redox biology. In vivo, GPX3 methylation predicts tumor xenograft sensitivity to platinum with regression of GPX3 knockdown xenografts with platinum treatment but continued growth of GPX3 wild type xenografts in the presence of platinum. These studies demonstrate the importance of GPX3 for CRC cells resistance to platinums and the potential utility of GPX3 methylation status as a predictive biomarker for platinum sensitivity in CRC.

  20. A link prediction approach to cancer drug sensitivity prediction.

    Science.gov (United States)

    Turki, Turki; Wei, Zhi

    2017-10-03

    Predicting the response to a drug for cancer disease patients based on genomic information is an important problem in modern clinical oncology. This problem occurs in part because many available drug sensitivity prediction algorithms do not consider better quality cancer cell lines and the adoption of new feature representations; both lead to the accurate prediction of drug responses. By predicting accurate drug responses to cancer, oncologists gain a more complete understanding of the effective treatments for each patient, which is a core goal in precision medicine. In this paper, we model cancer drug sensitivity as a link prediction, which is shown to be an effective technique. We evaluate our proposed link prediction algorithms and compare them with an existing drug sensitivity prediction approach based on clinical trial data. The experimental results based on the clinical trial data show the stability of our link prediction algorithms, which yield the highest area under the ROC curve (AUC) and are statistically significant. We propose a link prediction approach to obtain new feature representation. Compared with an existing approach, the results show that incorporating the new feature representation to the link prediction algorithms has significantly improved the performance.

  1. 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.

  2. RNA interference-mediated vascular endothelial growth factor-C reduction suppresses malignant progression and enhances mitomycin C sensitivity of bladder cancer T24 cells.

    Science.gov (United States)

    Zhang, Hui-hui; Qi, Fan; Shi, Ying-rui; Miao, Jian-guang; Zhou, Mi; He, Wei; Chen, Min-feng; Li, Yuan; Zu, Xiong-bing; Qi, Lin

    2012-06-01

    Vascular endothelial growth factor-C (VEGF-C) has been found to be significantly associated with lymphangiogenesis and regional lymph node metastasis in various human tumors. The present work was aimed to explore the role of VEGF-C in malignant progression of human bladder cancer T24 cell line. First, the expression of VEGF-C in T24 cells was detected by western blotting. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was employed to measure the cellular proliferation after treatment with various concentrations of recombinant human VEGF-C (rhVEGF-C). Then, lentivirus vector-based RNA interference (RNAi) was used to inhibit VEGF-C expression of T24 cells. The alterations of T24 cells regarding proliferation, invasiveness, and the apoptosis induced by mitomycin C (MMC) were evaluated. The results showed that the proliferation rate of T24 cells rose from 27.3% to 65.0%, with increasing rhVEGF-C concentration. T24 cells stably transfected with VEGF-C small interference RNA showed 85% reduction in VEGF-C mRNA expression (p T24 cells induced by MMC (p T24 cells, which is due to suppression of apoptosis and facilitation of migration, accompanied with upregulation of p38 MAPK and Akt phosphorylation. RNAi targeting VEGF-C could effectively suppress malignant progression and enhance chemosensitivity of T24 cells. Thus, inhibition of VEGF-C expression is a potential and promising therapeutic strategy for bladder cancer.

  3. Impaired SHP2-Mediated Extracellular Signal-Regulated Kinase Activation Contributes to Gefitinib Sensitivity of Lung Cancer Cells with Epidermal Factor Receptor-Activating Mutations

    OpenAIRE

    Lazzara, Matthew J.; Lane, Keara M.; Chan, Richard; Jasper, Paul J; Yaffe, Michael B.; Sorger, Peter K.; Jacks, Tyler E.; Neel, Benjamin G.; Lauffenburger, Douglas A.

    2010-01-01

    Most non–small cell lung cancers (NSCLC) display elevated expression of epidermal growth factor receptor (EGFR), but response to EGFR kinase inhibitors is predominantly limited to NSCLC harboring EGFR-activating mutations. These mutations are associated with increased activity of survival pathways, including phosphatidylinositol 3-kinase/AKT and signal transducer and activator of transcription 3/5. We report that EGFR-activating mutations also surprisingly lead to decreased ability to activat...

  4. Metabolic perturbation sensitizes human breast cancer to NK cell-mediated cytotoxicity by increasing the expression of MHC class I chain-related A/B

    OpenAIRE

    Fu, Dexue; Geschwind, Jean-Francois; Karthikeyan, Swathi; Miller, Eliyahu; Kunjithapatham, Rani; Wang, Zhijun; Ganapathy-Kanniappan, Shanmugasundaram

    2015-01-01

    Cleavage or shedding of the surface antigen, MHC class I chain-related (MIC) protein (A/B) has been known to be one of the mechanisms by which tumor cells escape host immune surveillance. Thus, any strategy to augment the surface expression of MICA/B could facilitate anticancer immune response. Here, we demonstrate that metabolic perturbation by the glycolytic inhibitor, 3-bromopyruvate (3-BrPA) augments the surface expression of MICA/B in human breast cancer cell lines, MDA-MB-231 and T47D. ...

  5. Propofol induces apoptosis and increases gemcitabine sensitivity in pancreatic cancer cells in vitro by inhibition of nuclear factor-κB activity

    Science.gov (United States)

    Du, Qi-Hang; Xu, Yan-Bing; Zhang, Meng-Yuan; Yun, Peng; He, Chang-Yao

    2013-01-01

    AIM: To investigate the effect of propofol on human pancreatic cells and the molecular mechanism of propofol action. METHODS: We used the human pancreatic cancer cell line MIAPaCa-2 for in vitro studies measuring growth inhibition and degree of apoptotic cell death induced by propofol alone, gemcitabine alone, or propofol followed by gemcitabine. All experiments were conducted in triplicate and carried out on three or more separate occasions. Data were means of the three or more independent experiments ± SE. Statistically significant differences were determined by two-tailed unpaired Student’s t test and defined as P propofol for 24 h followed by gemcitabine resulted in 24%-75% growth inhibition compared with 6%-18% when gemcitabine was used alone. Overall growth inhibition was directly correlated with apoptotic cell death. We also showed that propofol potentiated gemcitabine-induced killing by downregulation of nuclear factor-κB (NF-κB). In contrast, NF-κB was upregulated when pancreatic cancer cells were exposed to gemcitabine alone, suggesting a potential mechanism of acquired chemoresistance. CONCLUSION: Inactivation of the NF-κB signaling pathway by propofol might abrogate gemcitabine-induced activation of NF-κB, resulting in chemosensitization of pancreatic tumors to gemcitabine. PMID:24023491

  6. 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)....

  7. (II) complexes as sensitizers for dye sensitized solar cells

    Indian Academy of Sciences (India)

    electrical conversion efficiency. (η) of 10% at AM 1·5 solar radiation.12 Although. Z907 sensitized solar cell resulted in low efficiency. *For correspondence. J. Chem. Sci., Vol. 123, No. 1, January 2011, pp. 37–46. * Indian Academy of Sciences. 37 ...

  8. Benzo[a]pyrene sensitizes MCF7 breast cancer cells to induction of G1 arrest by the natural flavonoid eupatorin-5-methyl ether, via activation of cell signaling proteins and CYP1-mediated metabolism.

    Science.gov (United States)

    Androutsopoulos, Vasilis P; Tsatsakis, Aristeidis M

    2014-10-15

    Eupatorin-5-methyl ether (E5M) is a flavone containing 4 methoxy groups that is present in plants with medicinal activity, whereas luteolin (L) is a polyhydroxylated flavone commonly encountered in dietary products. In the present study we investigated the interaction of the two flavonoids with cytochrome P450 CYP1 enzymes in breast cancer MCF7 cells. Both compounds induced a dose dependent increase in CYP1A1 and CYP1B1 mRNA levels, as well as in EROD activity, a marker of CYP1 enzyme activity. Induction of cytochrome P450 CYP1 expression by E5M was accompanied by translocation of the ligand-activated transcription factor AhR to the nucleus, as demonstrated by confocal immunofluoresence. More importantly, although E5M was less active than L in inhibiting proliferation of MCF7 cells, when the cells were pretreated with the CYP1 inducer Benzo[a]pyrene (BaP) the potency of E5M was augmented. HPLC and LC-MS analysis revealed that E5M was metabolized to a major conversion product assigned E5M1 resulting from one step demethylation reaction in MCF7 cells whereas L metabolism by recombinant CYP1A1 did not reveal any metabolites. E5M1 production in BaP-induced MCF7 cells was attenuated in the presence of the CYP1A1 inhibitor α-napthoflavone. E5M further induced a dose dependent increase in the cell signaling proteins p21, JNK and p-JNK in MCF7 cells. This effect was enhanced in BaP pretreated cells and was associated with G1 arrest and a small percentage of apoptosis (3.5%). E5M antiproliferative effect in BaP pretreated cells was attenuated in the presence of the CYP1A1 inhibitor α-napthoflavone, as demonstrated by Western blotting and FACS analysis. Taken together the results demonstrate that BaP sensitizes MCF7 cells to E5M antiproliferative activity via enhanced induction of p21, JNK and p-JNK that in turn results by cytochrome P450 CYP1-mediated conversion to the metabolite E5M1. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  9. Squamous cell skin cancer

    Science.gov (United States)

    ... squamous cell cancer include: Having light-colored skin, blue or green eyes, or blond or red hair Long-term, daily sun exposure (such as in people who work outside) Many severe sunburns early in life Older age Having had many x-rays Chemical exposure A weakened immune system, especially in ...

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

    Directory of Open Access Journals (Sweden)

    McBride William H

    2005-07-01

    Full Text Available Abstract Background 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. Methods 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. Results 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. Conclusion We conclude that caspase-dependent cleavage of DNA-PKcs during apoptosis does not contribute to the radiosensitizing effects of MG-132.

  11. Cancer stem cell-like cells from a single cell of oral squamous carcinoma cell lines

    Energy Technology Data Exchange (ETDEWEB)

    Felthaus, O. [Department of Operative Dentistry and Periodontology, University of Regensburg (Germany); Department of Oral and Maxillofacial Surgery, University of Regensburg (Germany); Ettl, T.; Gosau, M.; Driemel, O. [Department of Oral and Maxillofacial Surgery, University of Regensburg (Germany); Brockhoff, G. [Department of Gynecology and Obstetrics, University of Regensburg (Germany); Reck, A. [Department of Oral and Maxillofacial Surgery, University of Regensburg (Germany); Zeitler, K. [Institute of Pathology, University of Regensburg (Germany); Hautmann, M. [Department of Radiotherapy, University of Regensburg (Germany); Reichert, T.E. [Department of Oral and Maxillofacial Surgery, University of Regensburg (Germany); Schmalz, G. [Department of Operative Dentistry and Periodontology, University of Regensburg (Germany); Morsczeck, C., E-mail: christian.morsczeck@klinik.uni-regensburg.de [Department of Operative Dentistry and Periodontology, University of Regensburg (Germany)

    2011-04-01

    Research highlights: {yields} Four oral squamous cancer cell lines (OSCCL) were analyzed for cancer stem cells (CSCs). {yields} Single cell derived colonies of OSCCL express CSC-marker CD133 differentially. {yields} Monoclonal cell lines showed reduced sensitivity for Paclitaxel. {yields} In situ CD133{sup +} cells are slow cycling (Ki67-) indicating a reduced drug sensitivity. {yields} CD133{sup +} and CSC-like cells can be obtained from single colony forming cells of OSCCL. -- Abstract: Resistance of oral squamous cell carcinomas (OSCC) to conventional chemotherapy or radiation therapy might be due to cancer stem cells (CSCs). The development of novel anticancer drugs requires a simple method for the enrichment of CSCs. CSCs can be enriched from OSCC cell lines, for example, after cultivation in serum-free cell culture medium (SFM). In our study, we analyzed four OSCC cell lines for the presence of CSCs. CSC-like cells could not be enriched with SFM. However, cell lines obtained from holoclone colonies showed CSC-like properties such as a reduced rate of cell proliferation and a reduced sensitivity to Paclitaxel in comparison to cells from the parental lineage. Moreover, these cell lines differentially expressed the CSC-marker CD133, which is also upregulated in OSCC tissues. Interestingly, CD133{sup +} cells in OSCC tissues expressed little to no Ki67, the cell proliferation marker that also indicates reduced drug sensitivity. Our study shows a method for the isolation of CSC-like cell lines from OSCC cell lines. These CSC-like cell lines could be new targets for the development of anticancer drugs under in vitro conditions.

  12. Alcohol and Cancer Stem Cells

    OpenAIRE

    Mei Xu; Jia Luo

    2017-01-01

    Heavy alcohol consumption has been associated with increased risk of several cancers, including cancer of the colon, rectum, female breast, oral cavity, pharynx, larynx, liver, and esophagus. It appears that alcohol exposure not only promotes carcinogenesis but also enhances the progression and aggressiveness of existing cancers. The molecular mechanisms underlying alcohol tumor promotion, however, remain unclear. Cancer stem cells (CSC), a subpopulation of cancer cells with self-renewal and ...

  13. ALDH+ tumor-initiating cells exhibiting gain in NOTCH1 gene copy number have enhanced regrowth sensitivity to a γ-secretase inhibitor and irinotecan in colorectal cancer.

    Science.gov (United States)

    Arcaroli, John J; Powell, Rebecca W; Varella-Garcia, Marileila; McManus, Martine; Tan, Aik Choon; Quackenbush, Kevin S; Pitts, Todd M; Gao, Dexiang; Spreafico, Anna; Dasari, Arvind; Touban, Basel M; Messersmith, Wells A

    2012-06-01

    The Notch signaling pathway has been shown to be upregulated in colorectal cancer (CRC) and important for the self-renewal of cancer stem cells. In this study, we evaluated the efficacy of PF-03084014, a γ-secretase inhibitor, in combination with irinotecan to identify the effects of treatment on tumor recurrence and the tumor-initiating population in our CRC preclinical explant model. The combination of PF-03084014 and irinotecan had the greatest effect at reducing tumor growth on four CRC tumors when compared with treatment with PF-03084014 or irinotecan alone. The combination significantly reduced tumor recurrence in two CRC explants (CRC001 and CRC036) after treatment was discontinued. Both of these tumors exhibited elevated baseline levels of Notch pathway activation as well as an increase in NOTCH1 gene copy number when compared with the two CRC explants (CRC026 and CRC027) where tumors reappeared quickly after termination of treatment. Isolation and injection of aldehyde dehydrogenase (ALDH(+) and ALDH(-)) cells in an in vivo explant model demonstrated that the ALDH(+) cell population were tumorigenic. Evaluation of the ALDH(+) cells after 28 days of treatment showed that the combination reduced the ALDH(+) population in the tumors that did not regrow. Furthermore, ALDH(+) cells from CRC001 and CRC027 were injected in vivo and treated immediately for 28 days. Two months after treatment, tumors were evident in the combination treatment group for CRC027 but not for CRC036. These results indicate the combination of PF-03084014 and irinotecan may be effective in reducing tumor recurrence in CRC patients whose tumors exhibit elevated levels of the Notch pathway. Copyright © 2012 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

  14. 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.

  15. Fruit based Dye Sensitized Solar Cells

    Science.gov (United States)

    Ung, M. C.; Sipaut, C. S.; Dayou, J.; Liow, K. S.; Kulip, J.; Mansa, R. F.

    2017-07-01

    Dye Sensitized Solar Cell (DSSC) was first discovered in 1991 by O’regan and Gratzel. This new type of solar cell was reported to have lower production cost with efficiency as high as 12% which is comparable to conventional silicon solar cell. Initially, it uses ruthenium dye as light sensitizer for the operation. However, DSSC with ruthenium dyes are facing environment friendly issues due to the toxic chemicals and costly purification in processing ruthenium dye. Regardless of the poor performance in DSSC, natural dyes which are easy to prepare, cheap and environmental friendly still appear to be an alternative as dye sensitizer. In this study, dye sensitized solar cells (DSSCs) were fabricated using anthocyanin source dyes extracted from several local fruits. All the extracts absorb a wide range of the visible light and ultraviolet spectrum. Therefore, all of the natural dyes show light absorption properties which is important for a dye sensitizer. A DSSC is comprised of conductive substrate, nanoporous semiconductor TiO2 layer, dye sensitizer, electrolyte with redox couple and a counter electrode with catalyst. In this study, the effect of different light source and different counter electrode are been investigated. However, it is vital to know that further research need to do more on the locally Borneo sourced dyes to evaluate and enhance their performance in Dye Sensitized Solar Cell.

  16. [Development of ultrasonic cancer therapy using ultrasound sensitive liposome].

    Science.gov (United States)

    Suzuki, Ryo; Oda, Yusuke; Utoguchi, Naoki; Maruyama, Kazuo

    2010-12-01

    Ultrasound (US) has been utilized as a useful tool for diagnosis and therapy. US mediated drug and gene delivery is paid to attention as a non-invasive system. The combination of US and microbubbles generated microjet stream by inducing disruption of bubbles and resulted in enhancing permeability of cell membrane. This phenomenon has been utilized as driving force for drug and gene delivery. Recently, we developed ultrasound sensitive liposome [Bubble liposome (BL)] containing perfluoropropane gas. US combined with BL could effectively transfer gene in vivo compared to conventional cationic liposomes. Using this method, we succeeded to obtain a therapeutic effect in cancer gene therapy with Interleukin-12 corded plasmid DNA. Therefore, it is expected that US combined with BL might be a useful non-viral vector system. From this result, the fusion of liposomal and ultrasound technologies would be important for establishment of advanced cancer therapy.

  17. Hepatocyte SLAMF3 reduced specifically the multidrugs resistance protein MRP-1 and increases HCC cells sensitization to anti-cancer drugs

    Science.gov (United States)

    Eugenio, Mélanie Simoes; Demey, Baptiste; Singh, Amrathlal Rabbind; Ossart, Christèle; Bagami, Mohammed Al; Regimbeau, Jean-Marc; Nguyen-Khac, Eric; Naassila, Mickael

    2016-01-01

    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. PMID:27081035

  18. 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.

  19. Endoplasmic reticulum stress could induce autophagy and apoptosis and enhance chemotherapy sensitivity in human esophageal cancer EC9706 cells by mediating PI3K/Akt/mTOR signaling pathway.

    Science.gov (United States)

    Zhou, Fang; Li, Yan-Hua; Wang, Jian-Jun; Pan, Jia; Lu, Hong

    2017-06-01

    The study was designed to explore the mechanism of tunicamycin-induced endoplasmic reticulum stress in human esophageal cancer EC9706 cells and EC109 cells, as well as its effects on cell autophagy, apoptosis, and chemoresistance. Tunicamycin-induced endoplasmic reticulum stress model was established in EC9706 and EC109 cell lines. Western blotting was employed to detect the expression of endoplasmic reticulum stress iconic protein GRP78. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was used to evaluate the effect of different cisplatin and tunicamycin concentrations on survival rate of EC9706 cells and EC109 cells. Autophagy was monitored using monodansylcadaverin and apoptosis was detected by flow cytometry. Western blotting was used to detect the expressions of endoplasmic reticulum stress-related proteins (PERK, eIF2α, and CHOP), PI3K/Akt/mTOR signaling pathway-related proteins, autophagy-related proteins (LC3-I/LC3-II, Beclin-1, and p62), and apoptosis-related proteins (Bcl-2, Bax, and cleaved caspase-3). Tunicamycin led to increased expression of GRP78. With tunicamycin treatment, phosphorylation of PERK and eIF2α and CHOP expression increased. Meanwhile, the increase in cytolysosome was concentration and time dependent. With the increased tunicamycin concentration, there were increased expressions of Bax and cleaved caspase-3, decreased expression of Bcl-2, and lower phosphorylation of PI3K/Akt/mTOR signaling pathway-related proteins. Therefore, it can be concluded that the combination of tunicamycin and cisplatin could improve the sensitivity of EC9706 cells and EC109 cells to cisplatin; PI3K inhibitor BEZ235 could enhance cell autophagy and apoptosis and increase cell sensitivity to cisplatin.

  20. Cancer Stem Cells and Epithelial Ovarian Cancer

    Directory of Open Access Journals (Sweden)

    Sheetal Dyall

    2010-01-01

    Full Text Available The cancer stem cell hypothesis is becoming more widely accepted as a model for carcinogenesis. Tumours are heterogeneous both at the molecular and cellular level, containing a small population of cells that possess highly tumourigenic “stem-cell” properties. Cancer stem cells (CSCs, or tumour-initiating cells, have the ability to self-renew, generate xenografts reminiscent of the primary tumour that they were derived from, and are chemoresistant. The characterisation of the CSC population within a tumour that drives its growth could provide novel target therapeutics against these cells specifically, eradicating the cancer completely. There have been several reports describing the isolation of putative cancer stem cell populations in several cancers; however, no defined set of markers has been identified that conclusively characterises “stem-like” cancer cells. This paper highlights the current experimental approaches that have been used in the field and discusses their limitations, with specific emphasis on the identification and characterisation of the CSC population in epithelial ovarian cancer.

  1. Cancer treatments transform residual cancer cell phenotype

    Directory of Open Access Journals (Sweden)

    Harless William W

    2011-01-01

    Full Text Available Abstract Background Physiologic wound repair and tissue regeneration are associated with distinct cellular behaviors triggered by tissue damage. Normally quiescent stem cells proliferate to regenerate damaged tissue, while relatively immobile epithelial cells can transform into a motile, tissue invasive phenotype through a partial epithelial-mesenchymal transition. These distinct cellular behaviors may have particular relevance to how cancer cells can be predicted to behave after treatments damaging a tumor. Presentation of the hypothesis Surgery, chemotherapy, and radiation therapy trigger highly conserved wound healing pathways that: (1 facilitate the phenotypic transformation of surviving cancer cells into a highly mobile, metastatic phenotype through an EMT or epithelial-mesenchymal transition and (2 induce residual cancer stem cell proliferation. Testing the hypothesis Tissue damage caused by cancer treatments will trigger the release of distinct cytokines with established roles in physiologic wound healing, EMT induction, and stem cell activation. They will be released rapidly after treatment and detectable in the patient's blood. Careful histologic evaluation of cancerous tissue before and after treatment will reveal cellular changes suggestive of EMT induction (down regulation of cytokeratin expression and cancer stem cell enrichment (stem cell markers upregulated. Implications of the hypothesis Cancer cells surviving treatment will be more capable of metastasis and resistant to conventional therapies than the pre-treatment population of cancer cells. These changes will develop rapidly after treatment and, in distinct contrast to selection pressures fostering such changes, be triggered by highly conserved wound repair signals released after tissue damage. This pattern of tissue (tumor repair may be amenable to treatment intervention at the time it is upregulated.

  2. Monitoring of epidermal growth factor receptor tyrosine kinase inhibitor-sensitizing and resistance mutations in the plasma DNA of patients with advanced non-small cell lung cancer during treatment with erlotinib

    DEFF Research Database (Denmark)

    Sorensen, Boe S; Wu, Lin; Wei, Wen

    2014-01-01

    BACKGROUND: The feasibility of monitoring epidermal growth factor receptor (EGFR) mutations in plasma DNA from patients with advanced non-small cell lung cancer (NSCLC) during treatment with erlotinib and its relation to disease progression was investigated. METHODS: The amount of EGFR-mutant DNA...... was tested in plasma DNA from patients with advanced NSCLC with allele-specific polymerase chain reaction assays. Blood samples from 23 patients with adenocarcinoma of NSCLC that carried tyrosine kinase inhibitor-sensitizing EGFR mutations were taken immediately before treatment with erlotinib. Additional...... blood samples were taken at timed intervals until erlotinib treatment was withdrawn. RESULTS: The amount of plasma DNA with sensitizing EGFR mutations was found to be reduced after the first cycle of erlotinib treatment in 22 of 23 patients (96%). No patients presented with the resistant T790M mutation...

  3. Stem cells and solid cancers.

    Science.gov (United States)

    McDonald, Stuart A C; Graham, Trevor A; Schier, Stefanie; Wright, Nicholas A; Alison, Malcolm R

    2009-07-01

    Recently, there have been significant advances in our knowledge of stem cells found in tissues that can develop solid tumours. In particular, novel stem cell markers have been identified for the first time identifying multipotential cells: a required characteristic of a stem cell. The scarcity of cancer stem cells has been questioned. Current dogma states that they are rare, but novel research has suggested that this may not be the case. Here, we review the latest literature on stem cells, particularly cancer stem cells within solid tumours. We discuss current thinking on how stem cells develop into cancer stem cells and how they protect themselves from doing so and do they express unique markers that can be used to detect stem cells. We attempt to put into perspective these latest advances in stem cell biology and their potential for cancer therapy.

  4. Identifying Determinants of PARP Inhibitor Sensitivity in Ovarian Cancer

    Science.gov (United States)

    2015-10-01

    Maryland 21702-5012 Approved for Public Release; Distribution Unlimited Identifying Determinants of PARP Inhibitor Sensitivity in Ovarian Cancer October...NOTES 14. ABSTRACT 15. SUBJECT TERMS Ovarian cancer , BRCA1, RAD51, PARP inhibitors, platinum, biomarkers, drug resistance 16. SECURITY CLASSIFICATION...Identifying Determinants of PARP Inhibitor Sensitivity in Ovarian Cancer Form Approved OMB No. 0704-0188 Public reporting burden for this collection of

  5. pH-Sensitive PEGylated liposomes for delivery of an acidic dinitrobenzamide mustard prodrug: Pathways of internalization, cellular trafficking and cytotoxicity to cancer cells.

    Science.gov (United States)

    Yang, Mimi M; Wilson, William R; Wu, Zimei

    2017-01-10

    This paper aims to develop and evaluate a pH-sensitive PEGylated liposomal (pPSL) system for tumor-targeted intracellular delivery of SN25860, a weakly acidic, poorly water-soluble dinitrobenzamide mustard prodrug which is activated by the E. coli nitroreductase nfB. pPSL and non pH-sensitive liposomes (nPSL), as reference, were formulated by thin-film hydration; an active drug loading method was developed with the aid of solubilizers. Cytotoxicity was evaluated in an nfsB-transfected EMT6 mouse mammary carcinoma cell line. Cellular uptake of liposomes was evaluated by both high performance liquid chromatography and flow cytometry. Intracellular trafficking was visualised by confocal microscopy. High drug loading (7.0±0.2% w/w) was achieved after systematic optimization of drug loading conditions. pPSL-SN25860 demonstrated a 21 and 24- fold increase in antiproliferative potency compared to nPSL-SN25860 and free drug, respectively. Cells treated with pPSL had a 1.6-2.5- fold increase in intracellular drug concentration compared to nPSL. This trend was consistent with flow cytometry results. Cells treated with chlorpromazine demonstrated reduced uptake of both nPSL (40%) and pPSL (46%), indicating clathrin-mediated endocytosis was the major pathway. Confocal microscopy showed that pPSL had not only undergone faster and greater endocytosis than nPSL but was also homogeneously distributed in the cytosol and nuclei suggesting endosome escape, in contrast to nPSL. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. 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...... 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...... 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...

  7. 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

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

    Science.gov (United States)

    Flusberg, Deborah A.; Sorger, Peter K.

    2013-06-01

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

  9. The telomerase inhibitor imetelstat depletes cancer stem cells in breast and pancreatic cancer cell lines.

    Science.gov (United States)

    Joseph, Immanual; Tressler, Robert; Bassett, Ekaterina; Harley, Calvin; Buseman, Christen M; Pattamatta, Preeti; Wright, Woodring E; Shay, Jerry W; Go, Ning F

    2010-11-15

    Cancer stem cells (CSC) are rare drug-resistant cancer cell subsets proposed to be responsible for the maintenance and recurrence of cancer and metastasis. Telomerase is constitutively active in both bulk tumor cell and CSC populations but has only limited expression in normal tissues. Thus, inhibition of telomerase has been shown to be a viable approach in controlling cancer growth in nonclinical studies and is currently in phase II clinical trials. In this study, we investigated the effects of imetelstat (GRN163L), a potent telomerase inhibitor, on both the bulk cancer cells and putative CSCs. When breast and pancreatic cancer cell lines were treated with imetelstat in vitro, telomerase activity in the bulk tumor cells and CSC subpopulations were inhibited. Additionally, imetelstat treatment reduced the CSC fractions present in the breast and pancreatic cell lines. In vitro treatment with imetelstat, but not control oligonucleotides, also reduced the proliferation and self-renewal potential of MCF7 mammospheres and resulted in cell death after telomerase activity expression levels or telomere length of CSCs and bulk tumor cells in these cell lines did not correlate with the increased sensitivity of CSCs to imetelstat, suggesting a mechanism of action independent of telomere shortening for the effects of imetelstat on the CSC subpopulations. Our results suggest that imetelstat-mediated depletion of CSCs may offer an alternative mechanism by which telomerase inhibition may be exploited for cancer therapy. Copyright © 2010 AACR.

  10. CXCR4 Inhibition with AMD3100 Sensitizes Prostate Cancer to Docetaxel Chemotherapy

    Directory of Open Access Journals (Sweden)

    Urszula M. Domanska

    2012-08-01

    Full Text Available Several in vitro and in vivo models have revealed the key role of CXCR4/CXCL12 axis in tumor-stroma interactions. Stromal cells present in the tumor microenvironment express high levels of CXCL12 protein, directly stimulating proliferation and migration of CXCR4-expressing cancer cells. This specific prosurvival influence of stromal cells on tumor cells is thought to protect them from cytotoxic chemotherapy and is postulated as a possible explanation for the minimal residual disease in hematological and solid cancers. Therefore, CXCR4/CXCL12 signaling is an attractive therapeutic target in cancer, as proven in preclinical leukemia mouse models, where CXCR4 inhibition sensitized cancer cells to conventional chemotherapy. This study investigates whether inhibition of CXCR4 with the specific inhibitor AMD3100 sensitizes human prostate cancer cells to docetaxel. We showed that both mouse and human stromal cell lines have a protective effect on PC3-luc cells by promoting their survival after chemotherapy. Furthermore, we demonstrated that AMD3100 sensitizes PC3-luc cells to docetaxel. In a subcutaneous xenograft mouse model of human prostate carcinoma, we showed that a combination of docetaxel and AMD3100 exerts increased antitumor effect compared with docetaxel alone. We concluded that CXCR4 inhibition chemosensitizes prostate cancer cells, both in vitro and in vivo. To explore the relevance of these findings, we analyzed CXCR4 expression levels in human prostate cancer samples. We found that cancer cells present in bone metastatic lesions express higher CXCR4 levels relative to the cells present in primary tumors and lymph node metastatic lesions. These findings underscore the potential of CXCR4 inhibitors as chemosensitizing agents.

  11. Sensitive-cell-based fish chromatophore biosensor

    Science.gov (United States)

    Plant, Thomas K.; Chaplen, Frank W.; Jovanovic, Goran; Kolodziej, Wojtek; Trempy, Janine E.; Willard, Corwin; Liburdy, James A.; Pence, Deborah V.; Paul, Brian K.

    2004-07-01

    A sensitive biosensor (cytosensor) has been developed based on color changes in the toxin-sensitive colored living cells of fish. These chromatophores are highly sensitive to the presence of many known and unknown toxins produced by microbial pathogens and undergo visible color changes in a dose-dependent manner. The chromatophores are immobilized and maintained in a viable state while potential pathogens multiply and fish cell-microbe interactions are monitored. Low power LED lighting is used to illuminate the chromatophores which are magnified using standard optical lenses and imaged onto a CCD array. Reaction to toxins is detected by observing changes is the total area of color in the cells. These fish chromatophores are quite sensitive to cholera toxin, Staphococcus alpha toxin, and Bordatella pertussis toxin. Numerous other toxic chemical and biological agents besides bacterial toxins also cause readily detectable color effects in chromatophores. The ability of the chromatophore cell-based biosensor to distinguish between different bacterial pathogens was examined. Toxin producing strains of Salmonella enteritis, Vibrio parahaemolyticus, and Bacillus cereus induced movement of pigmented organelles in the chromatophore cells and this movement was measured by changes in the optical density over time. Each bacterial pathogen elicited this measurable response in a distinctive and signature fashion. These results suggest a chromatophore cell-based biosensor assay may be applicable for the detection and identification of virulence activities associated with certain air-, food-, and water-borne bacterial pathogens.

  12. 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.

  13. 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.

  14. A Noise-Filtering Approach for Cancer Drug Sensitivity Prediction

    OpenAIRE

    Turki, Turki; Wei, Zhi

    2016-01-01

    Accurately predicting drug responses to cancer is an important problem hindering oncologists' efforts to find the most effective drugs to treat cancer, which is a core goal in precision medicine. The scientific community has focused on improving this prediction based on genomic, epigenomic, and proteomic datasets measured in human cancer cell lines. Real-world cancer cell lines contain noise, which degrades the performance of machine learning algorithms. This problem is rarely addressed in th...

  15. 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.

  16. 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

    2012-01-01

    According to the cancer stem cell theory, cancers can be initiated by cancer stem cells. This makes cancer stem cells prime targets for therapeutic intervention. Eradicating cancer stem cells by efficient targeting agents may have the potential to cure cancer. In this review, we summarize recent breakthroughs that have improved our understanding of cancer stem cells, and we discuss the therapeutic strategy of targeting cancer stem cells, a promising future direction for cancer stem cell research. PMID:22507219

  17. The impact of insulin on chemotherapeutic sensitivity to 5-fluorouracil in gastric cancer cell lines SGC7901, MKN45 and MKN28

    OpenAIRE

    Wei, Zhao; Liang, Li; Junsong, Liu; Rui, Chen; Shuai, Chang; Guanglin, Qiu; Shicai, He; Zexing, Wang; Jin, Wang; Xiangming, Che; Shufeng, Wang

    2015-01-01

    Background The role of insulin in the pathogenesis of cancer has been increasingly emphasized because of the high incidence of obesity and metabolic syndrome and their correlated complication including cancer. This study aimed to explore the impact of insulin on chemoresistance to 5-fluorouracil in gastric cancer and the possible mechanisms. Methods Tissue samples of gastric cancer and adjacent normal gastric mucosa from patients with or without obesity were performed immunohistochemical stai...

  18. Determination of Cancer Cell-Based pH-Sensitive Fluorescent Carbon Nanoparticles of Cross-Linked Polydopamine by Fluorescence Sensing of Alkaline Phosphatase Activity on Coated Surfaces and Aqueous Solution.

    Science.gov (United States)

    Kang, Eun Bi; Choi, Cheong A; Mazrad, Zihnil Adha Islamy; Kim, Sung Han; In, Insik; Park, Sung Young

    2017-12-19

    The tumor-specific sensitive fluorescence sensing of cellular alkaline phosphatase (ALP) activity on the basis of host-guest specific and pH sensitivity was conducted on coated surfaces and aqueous states. Cross-linked fluorescent nanoparticles (C-FNP) consisting of β-cyclodextrin (β-CD)/boronic acid (BA) and fluorescent hyaluronic acid [FNP(HA)] were conjugated to fluorescent polydopamine [FNP(pDA)]. To determine the quenching effect of this system, hydrolysis of 4-nitrophenyl phosphate (NPP) to 4-nitrophenol (NP) was performed in the cavity of β-CD in the presence of ALP activated photoinduced electron transfer (PET) between NP and C-FNP. At an ALP level of 30-1000 U/L, NP caused off-emission of C-FNP because of their specific host-guest recognition. Fluorescence can be recovered under pH shock due to cleavage of the diol bond between β-CD and BA, resulting in release of NP from the fluorescent system. Sensitivity of the assays was assessed by confocal imaging not only in aqueous states, but also for the first time on coated surfaces in MDAMB-231 and MDCK cells. This novel system demonstrated high sensitivity to ALP through generation of good electron donor/acceptor pair during the PET process. Therefore, this fluorescence sensor system can be used to enhance ALP monitoring and cancer diagnosis on both coated surfaces and in aqueous states in clinical settings.

  19. Comparative analysis of cell morphology in sputum samples homogenized with dithiothreitol, N-acetyl-L cysteine, Cytorich(®) red preservative and in cellblock preparations to enhance the sensitivity of sputum cytology for the diagnosis of lung cancer.

    Science.gov (United States)

    Saraswathy Veena, Vamadevan; Sara George, Preethi; Jayasree, Kattoor; Sujathan, Kunjuraman

    2015-07-01

    Lung cancer claims highest rate of cancer related mortality worldwide, mainly due to late diagnosis and distant metastasis. Sputum cytology is the simplest, non-invasive and cost effective technique but it has low sensitivity due to lack of robust processing methods to retrieve all the diagnostic materials clogged in mucus, inflammatory exudates and blood. This study have compared conventional pick and smear method of sputum processing with samples prepared by homogenization methods using N-acetyl-l-cysteine, Dithiothreitol (DTT), CytoRich red solution and cell blocks (CBs) with respect to screening time, quality of staining, cellularity, smear background, nuclear and cytoplasmic morphology preservation, and diagnostic efficacy. The significance of CB prepared from homogenised samples for immunocytochemistry, protein extraction, Genomic DNA and RNA extraction were also evaluated on a cohort 3,185 samples. The significance of the morphological features in each of the techniques was statistically analysed using SPSS 11 software. The smear background clarity, staining quality and diagnostic efficacy of samples processed in red solution was found to be superior to the conventional method (P extraction were found possible in CBs as well as from the cell suspension. A combined analysis of smears and CBs found to improve the sensitivity of sputum cytology. The study suggests homogenization of sputum in CytoRich ® red solution and cellblock preparations routinely for all samples to improve the sensitivity of sputum cytology. IHC and DNA extraction can be performed in sputum samples suggesting the role of sputum samples for ancillary techniques. © 2015 Wiley Periodicals, Inc.

  20. Knockdown of OCT4 may sensitize NSCLC cells to cisplatin.

    Science.gov (United States)

    Liu, X; Ma, M; Duan, X; Zhang, H; Yang, M

    2017-05-01

    Cisplatin is commonly used in non-small-cell lung cancer (NSCLC) chemotherapy; however, chemoresistance to cisplatin remains a great clinical challenge. Octamer-binding protein 4 (OCT4) has been reported to be overexpressed in NSCLC. In this study, we aimed to investigate the potential role of OCT4 in NSCLC with chemoresistance to cisplatin. Expressions of OCT4 was detected in NSCLC tissues and cell lines. We utilized siRNA to knock down OCT4 expression in human NSCLC cells and analyzed their phenotypic changes. We found that the difference of OCT4 expression between NSCLC and the adjacent non-tumourous tissues was statistically significant. Knockdown of OCT4 in NSCLC cells could decrease cell proliferation, and potentiate apoptosis induced by cisplatin, suggesting OCT4 may contribute to cisplatin resistance in NSCLC. Our findings indicate that targeting OCT4 could improve cisplatin effect in NSCLC, confirming their role in modulating cisplatin sensitivity.

  1. Paper-based plasmonic platform for sensitive, noninvasive, and rapid cancer screening.

    Science.gov (United States)

    Liu, Qian; Wang, Jiahong; Wang, Beike; Li, Zhe; Huang, Hao; Li, Chengzhang; Yu, Xuefeng; Chu, Paul K

    2014-04-15

    Surface-enhanced Raman scattering (SERS) fingerprints of individual molecules offer the possibility of multiplexing as well as cancer screening. A highly sensitive, noninvasive, and rapid cancer screening platform encompassing exfoliative cytology and paper-based SERS technology is described. The SERS substrate which consists of plasmonic gold nanorods (GNRs) adsorbed on a piece of filter paper forms the flexible and three-dimensional heterogeneous scaffold for cancer screening. Different and reproducible SERS spectra are obtained from normal and cancerous cells due to specific biomolecular changes in cancerous cells. A diagnostic algorithm based on the ratio of the spectra values is adopted to distinguish between cells exfoliated from 20 normal and cancerous tissues, and a high sensitivity of 100% and specificity of 100% are achieved by I1600/1440 (peak ratio of signals at 1600-1440 cm(-1)) and I1440/1340 (1440-1340 cm(-1)), which is better than I1600/1340 (1600-1340 cm(-1)) with a sensitivity of 70% and specificity of 60%. The combination of exfoliative cytology and paper-based plasmonic technology enables highly sensitive, rapid, and non-invasive cancer screening and has large clinical potential. © 2013 Published by Elsevier B.V.

  2. TAK1 inhibitor 5Z-7-oxozeaenol sensitizes cervical cancer to doxorubicin-induced apoptosis.

    Science.gov (United States)

    Guan, Shan; Lu, Jiaxiong; Zhao, Yanling; Woodfield, Sarah E; Zhang, Huiyuan; Xu, Xin; Yu, Yang; Zhao, Jing; Bieerkehazhi, Shayahati; Liang, Haoqian; Yang, Jianhua; Zhang, Fuchun; Sun, Surong

    2017-05-16

    Aberrant activation of nuclear factor-κB (NF-κB) allows cancer cells to escape chemotherapy-induced cell death and acts as one of the major mechanisms of acquired chemoresistance in cervical cancer. TAK1, a crucial mediator that upregulates NF-κB activation in response to cellular genotoxic stress, is required for tumor cell viability and survival. Herein, we examined whether TAK1 inhibition is a potential therapeutic strategy for treating cervical cancer. We found that TAK1 inhibitor 5Z-7-oxozeaenol significantly augmented the cytotoxic effects of Dox in a panel of cervical cancer cell lines. Treatment with 5Z-7-oxozeaenol hindered Dox-induced NF-κB activation and promoted Dox-induced apoptosis in cervical cancer cells. Moreover, 5Z-7-oxozeaenol showed similar effects in both positive and negative human papillomavirus-infected cervical cancer cells. Taken together, our results provide evidence that TAK1 inhibition significantly sensitizes cervical cancer cells to chemotherapy-induced cell death and supports the use of TAK1 inhibitor with current chemotherapies in the clinic for patients with refractory cervical cancer.

  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. Platinum-sensitive recurrence in ovarian cancer: The role of tumor microenvironment

    Directory of Open Access Journals (Sweden)

    Jeremy eChien

    2013-09-01

    Full Text Available Despite several advances in the understanding of ovarian cancer pathobiology, in terms of driver genetic alterations in high-grade serous cancer, histology heterogeneity of epithelial ovarian cancer, cell-of-origin for ovarian cancer, the survival rate from ovarian cancer is disappointingly low when compared to that of breast or prostate cancer. One of the factors contributing to the poor survival rate from ovarian cancer is the development of chemotherapy resistance following several rounds of chemotherapy. Although unicellular drug resistance mechanisms contribute to chemotherapy resistance, tumor microenvironment and the extracellular matrix, in particular, is emerging as a significant determinant of a tumor’s response to chemotherapy. In this review, we discuss the potential role of the tumor microenvironment in ovarian cancer recurrence and resistance to chemotherapy. Finally, we propose an alternative view of platinum-sensitive recurrence to describe a potential role of the extracellular matrix in the process.

  5. 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 ... Horn L, Eisenberg R, Gius D, et al. Cancer of the lung. In: Niederhuber JE, Armitage JO, Doroshow JH, Kastan ...

  6. Silencing long non-coding RNA ROR improves sensitivity of non-small-cell lung cancer to cisplatin resistance by inhibiting PI3K/Akt/mTOR signaling pathway.

    Science.gov (United States)

    Shi, Hui; Pu, Jin; Zhou, Xiao-Li; Ning, Yun-Ye; Bai, Chong

    2017-05-01

    This study aimed to investigate the effects of long non-coding RNA ROR (regulator of reprogramming) on cisplatin (DDP) resistance in patients with non-small-cell lung cancer by regulating PI3K/Akt/mTOR signaling pathway. Human cisplatin-resistant A549/DDP cell lines were selected and divided into control group, negative control group, si-ROR group, ROR over-expression group, Wortmannin group, and ROR over-expression + Wortmannin group. MTT assay was used to determine the optimum inhibitory concentration of DDP. Quantitative real-time polymerase chain reaction and western blotting were applied to detect expressions of long non-coding RNA ROR, PI3K, Akt, and mTOR. Colony-forming assay, scratch test, Transwell assay, and flow cytometry were conducted to detect cell proliferation, migration, invasion, and apoptosis, respectively. Tumor-formation assay was performed to detect the growth of transplanted tumors. Long non-coding RNA ROR expression was high in human A549/DDP cell lines. Compared with the control and negative control groups, the mRNA and protein expressions of PI3K, Akt, mTOR, and bcl-2 decreased, whereas the mRNA and protein expression of bax and the sensitivity of cells to DDP significantly increased. Cell proliferation, migration, and invasion abilities decreased in the si-ROR and Wortmannin groups. In comparison with control and negative control groups, the mRNA and protein expressions of PI3K, Akt, mTOR, and bcl-2 increased, whereas the mRNA and protein expressions of bax decreased, the sensitivity of cells to DDP significantly increased, and cell proliferation, migration, and invasion abilities decreased in the ROR over-expression group. For nude mice in tumor-formation assay, compared with control and negative control groups, the tumor weight was found to be lighter (1.03 ± 0.15) g, the protein expressions of PI3K, Akt, mTOR, and bcl-2 decreased, and the protein expression of bax increased in the si-ROR group. Long non-coding RNA ROR may affect

  7. Mechanotransduction in cancer stem cells.

    Science.gov (United States)

    Hao, Jin; Zhang, Yueling; Ye, Rui; Zheng, Yingcheng; Zhao, Zhihe; Li, Juan

    2013-09-01

    The cancer stem cell (CSC) concept, which arose about a decade ago, proposes that tumor growth is sustained by a subpopulation of highly malignant cells. These cells, termed CSCs, are capable of extensive self-renewal that contributes to metastasis and treatment resistance. Therefore, therapeutic strategies that target CSCs should be developed for improving outcomes of cancer patients. Recent progress has highlighted the importance of physical properties of the extracellular matrix and mechanotransduction pathway in cancer cells during cancer development. On the other hand, the significance of CXCR1, an upstream signal of FAK/PI3K/Akt has been revealed in CSCs. FAK/PI3K/Akt is a key signal mediator in mechanotransduction pathway. Therefore, mechanotransduction could be a new target for CSCs, and would be an innovative way to treat cancer by inhibiting FAK/PI3K/Akt. © 2013 International Federation for Cell Biology.

  8. 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 ...

  9. 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.

  10. Aptamer-Functionalized Fluorescent Silica Nanoparticles for Highly Sensitive Detection of Leukemia Cells

    Science.gov (United States)

    Tan, Juntao; Yang, Nuo; Hu, Zixi; Su, Jing; Zhong, Jianhong; Yang, Yang; Yu, Yating; Zhu, Jianmeng; Xue, Dabin; Huang, Yingying; Lai, Zongqiang; Huang, Yong; Lu, Xiaoling; Zhao, Yongxiang

    2016-06-01

    A simple, highly sensitive method to detect leukemia cells has been developed based on aptamer-modified fluorescent silica nanoparticles (FSNPs). In this strategy, the amine-labeled Sgc8 aptamer was conjugated to carboxyl-modified FSNPs via amide coupling between amino and carboxyl groups. Sensitivity and specificity of Sgc8-FSNPs were assessed using flow cytometry and fluorescence microscopy. These results showed that Sgc8-FSNPs detected leukemia cells with high sensitivity and specificity. Aptamer-modified FSNPs hold promise for sensitive and specific detection of leukemia cells. Changing the aptamer may allow the FSNPs to detect other types of cancer cells.

  11. Nanotechniques Inactivate Cancer Stem Cells

    Science.gov (United States)

    Goltsev, Anatoliy N.; Babenko, Natalya N.; Gaevskaya, Yulia A.; Bondarovich, Nikolay A.; Dubrava, Tatiana G.; Ostankov, Maksim V.; Chelombitko, Olga V.; Malyukin, Yuriy V.; Klochkov, Vladimir K.; Kavok, Nataliya S.

    2017-06-01

    One of the tasks of current oncology is identification of cancer stem cells and search of therapeutic means capable of their specific inhibition. The paper presents the data on phenotype characteristics of Ehrlich carcinoma cells as convenient and easy-to-follow model of tumor growth. The evidence of cancer stem cells as a part of Ehrlich carcinoma and significance of CD44+ and CD44- subpopulations in maintaining the growth of this type of tumor were demonstrated. A high (tenfold) tumorigenic activity of the Ehrlich carcinoma CD44+ cells if compared to CD44- cells was proven. In this pair of comparison, the CD44+ cells had a higher potential of generating in peritoneal cavity of CD44high, CD44+CD24-, CD44+CD24+ cell subpopulations, highlighting the presence of cancer stem cells in a pool of CD44+ cells.

  12. Multitask learning improves prediction of cancer drug sensitivity.

    Science.gov (United States)

    Yuan, Han; Paskov, Ivan; Paskov, Hristo; González, Alvaro J; Leslie, Christina S

    2016-08-23

    Precision oncology seeks to predict the best therapeutic option for individual patients based on the molecular characteristics of their tumors. To assess the preclinical feasibility of drug sensitivity prediction, several studies have measured drug responses for cytotoxic and targeted therapies across large collections of genomically and transcriptomically characterized cancer cell lines and trained predictive models using standard methods like elastic net regression. Here we use existing drug response data sets to demonstrate that multitask learning across drugs strongly improves the accuracy and interpretability of drug prediction models. Our method uses trace norm regularization with a highly efficient ADMM (alternating direction method of multipliers) optimization algorithm that readily scales to large data sets. We anticipate that our approach will enhance efforts to exploit growing drug response compendia in order to advance personalized therapy.

  13. 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.

  14. Characterization of the cell growth inhibitory effects of a novel DNA-intercalating bipyridyl-thiourea-Pt(II) complex in cisplatin-sensitive and -resistant human ovarian cancer cells.

    Science.gov (United States)

    Marverti, Gaetano; Ligabue, Alessio; Montanari, Monica; Guerrieri, Davide; Cusumano, Matteo; Di Pietro, Maria Letizia; Troiano, Leonarda; Di Vono, Elena; Iotti, Stefano; Farruggia, Giovanna; Wolf, Federica; Monti, Maria Giuseppina; Frassineti, Chiara

    2011-02-01

    The cellular effects of a novel DNA-intercalating agent, the bipyridyl complex of platinum(II) with diphenyl thiourea, [Pt(bipy)(Ph(2)-tu)(2)]Cl(2), has been analyzed in the cisplatin (cDDP)-sensitive human ovarian carcinoma cell line, 2008, and its -resistant variant, C13* cells, in which the highest accumulation and cytotoxicity was found among six related bipyridyl thiourea complexes. We also show here that this complex causes reactive oxygen species to form and inhibits topoisomerase II activity to a greater extent in the sensitive than in the resistant line. The impairment of this enzyme led to DNA damage, as shown by the comet assay. As a consequence, cell cycle distribution has also been greatly perturbed in both lines. Morphological analysis revealed deep cellular derangement with the presence of cellular masses, together with increased membrane permeability and depolarization of the mitochondrial membrane. Some of these effects, sometimes differentially evident between the two cell lines, might also be related to the decrease of total cell magnesium content caused by this thiourea complex both in sensitive and resistant cells, though the basal content of this ion was higher in the cDDP-resistant line. Altogether these results suggest that this compound exerts its cytotoxicity by mechanisms partly mediated by the resistance phenotype. In particular, cDDP-sensitive cells were affected mostly by impairing topoisomerase II activity and by increasing membrane permeability and the formation of reactive oxygen species; conversely, mitochondrial impairment appeared to play the most important role in the action of complex F in resistant cells.

  15. 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...

  16. Melatonin sensitizes H1975 non-small-cell lung cancer cells harboring a T790M-targeted epidermal growth factor receptor mutation to the tyrosine kinase inhibitor gefitinib.

    Science.gov (United States)

    Yun, Miyong; Kim, Eun-Ok; Lee, Duckgue; Kim, Ji-Hyun; Kim, Jaekwang; Lee, Hyemin; Lee, Jihyun; Kim, Sung-Hoon

    2014-01-01

    The use of tyrosine kinase inhibitors (TKIs) to target active epidermal growth factor receptor (EGFR)-harbouring mutations has been effective in patients with advanced non-small-cell lung cancer (NSCLC). However, the use of TKIs in NSCLS patients with somatic EGFR mutations, particularly T790M, causes drug resistance. Thus, in the present study, we investigated overcoming resistance against the TKI gefitinib by combination treatment with melatonin in H1975 NSCLC cells harbouring the T790M somatic mutation. H1975 and HCC827 cells were treated with melatonin in combination with gefitinib, and cell viability, cell cycle progression, apoptosis, and EGFR, AKT, p38, Bcl-2, Bcl-xL, caspase 3 and Bad protein levels were examined. Treatment with melatonin dose-dependently decreased the viability of H1975 cells harbouring the T790M somatic mutation compared to HCC827 cells with an EGFR active mutation. Melatonin-mediated cell death resulted in decreased phosphorylation of EGFR and Akt, leading to attenuated expression of survival proteins, such as Bcl-2, Bcl-xL and survivin, and activated caspase 3 in H1975 cells, but not in HCC827 cells. However, we did not observe a significant change in expression of cell cycle proteins, such as cyclin D, cyclin A, p21 and CDK4 in H1975 cells. Surprisingly, co-treatment of gefitinib with melatonin effectively decreased the viability of H1975 cells, but not HCC827 cells. Moreover, co-treatment of H1975 cells caused consistent down-regulation of EGFR phosphorylation and induced apoptosis compared to treatment with gefitinib or melatonin alone. Our findings demonstrate that melatonin acts as a potent chemotherapeutic agent by sensitising to gefitinib TKI-resistant H1975 cells that harbour a EGFR T790M mutation. © 2014 S. Karger AG, Basel.

  17. Melatonin Sensitizes H1975 Non-Small-Cell Lung Cancer Cells Harboring a T790M-Targeted Epidermal Growth Factor Receptor Mutation to the Tyrosine Kinase Inhibitor Gefitinib

    Directory of Open Access Journals (Sweden)

    Miyong Yun

    2014-08-01

    Full Text Available Background/Aims: The use of tyrosine kinase inhibitors (TKIs to target active epidermal growth factor receptor (EGFR-harbouring mutations has been effective in patients with advanced non-small-cell lung cancer (NSCLC. However, the use of TKIs in NSCLS patients with somatic EGFR mutations, particularly T790M, causes drug resistance. Thus, in the present study, we investigated overcoming resistance against the TKI gefitinib by combination treatment with melatonin in H1975 NSCLC cells harbouring the T790M somatic mutation. Methods: H1975 and HCC827 cells were treated with melatonin in combination with gefitinib, and cell viability, cell cycle progression, apoptosis, and EGFR, AKT, p38, Bcl-2, Bcl-xL, caspase 3 and Bad protein levels were examined. Results: Treatment with melatonin dose-dependently decreased the viability of H1975 cells harbouring the T790M somatic mutation compared to HCC827 cells with an EGFR active mutation. Melatonin-mediated cell death resulted in decreased phosphorylation of EGFR and Akt, leading to attenuated expression of survival proteins, such as Bcl-2, Bcl-xL and survivin, and activated caspase 3 in H1975 cells, but not in HCC827 cells. However, we did not observe a significant change in expression of cell cycle proteins, such as cyclin D, cyclin A, p21 and CDK4 in H1975 cells. Surprisingly, co-treatment of gefitinib with melatonin effectively decreased the viability of H1975 cells, but not HCC827 cells. Moreover, co-treatment of H1975 cells caused consistent down-regulation of EGFR phosphorylation and induced apoptosis compared to treatment with gefitinib or melatonin alone. Conclusions: Our findings demonstrate that melatonin acts as a potent chemotherapeutic agent by sensitising to gefitinib TKI-resistant H1975 cells that harbour a EGFR T790M mutation.

  18. Multifaceted Interpretation of Colon Cancer Stem Cells

    OpenAIRE

    Hatano, Yuichiro; Fukuda, Shinya; Hisamatsu, Kenji; Hirata, Akihiro; Hara, Akira; Tomita, Hiroyuki

    2017-01-01

    Colon cancer is one of the leading causes of cancer-related deaths worldwide, despite recent advances in clinical oncology. Accumulating evidence sheds light on the existence of cancer stem cells and their role in conferring therapeutic resistance. Cancer stem cells are a minor fraction of cancer cells, which enable tumor heterogeneity and initiate tumor formation. In addition, these cells are resistant to various cytotoxic factors. Therefore, elimination of cancer stem cells is difficult but...

  19. Semiconductor quantum dot-sensitized solar cells

    Directory of Open Access Journals (Sweden)

    Jianjun Tian

    2013-10-01

    Full Text Available 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.

  20. 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.

  1. Retinoic acid receptor alpha amplifications and retinoic acid sensitivity in breast cancers.

    Science.gov (United States)

    Alsafadi, Samar; Even, Caroline; Falet, Coralie; Goubar, Aicha; Commo, Frédéric; Scott, Véronique; Quidville, Virginie; Albiges, Laurence; Dieci, Maria-Vittoria; Guegan, Justine; Lazar, Vladimir; Ahomadegbe, Jean-Charles; Delaloge, Suzette; André, Fabrice

    2013-10-01

    Molecular segmentation of breast cancer allows identification of small groups of patients who present high sensitivity to targeted agents. A patient, with chemo- and trastuzumab-resistant HER2-overexpressing breast cancer, who presented concomitant acute promyelocytic leukemia, showed a response in her breast lesions to retinoic acid, arsenic, and aracytin. We therefore investigated whether RARA gene amplification could be associated with sensitivity to retinoic acid derivatives in breast cancers. Array comparative genomic hybridization and gene expression arrays were used to characterize RARA amplifications and expression in 103 breast cancer samples. In vitro activity of ATRA was characterized in T47D, SKBR3, and BT474 cell lines. Retinoic acid receptor alpha was gained or amplified in 27% of HER2-positive and 13% of HER2-negative breast cancer samples. Retinoic acid receptor alpha can be coamplified with HER2. Retinoic acid receptor alpha copy number changes could be correlated with messenger RNA expression. All-trans-retinoic acid reduced cell viability of RARA-amplified, but not RARA-normal, cell lines through apoptosis. Gene expression arrays showed that ATRA-induced apoptosis in RARA-amplified cell lines was related to an increase in CASP1 and IRF1. The results of this study suggest that breast cancers exhibiting RARA amplifications could be sensitive to retinoic acid. A phase II trial will evaluate this hypothesis in the clinical setting. Copyright © 2013 Elsevier Inc. All rights reserved.

  2. Milk stimulates growth of prostate cancer cells in culture.

    Science.gov (United States)

    Tate, Patricia L; Bibb, Robert; Larcom, Lyndon L

    2011-11-01

    Concern has been expressed about the fact that cows' milk contains estrogens and could stimulate the growth of hormone-sensitive tumors. In this study, organic cows' milk and two commercial substitutes were digested in vitro and tested for their effects on the growth of cultures of prostate and breast cancer cells. Cows' milk stimulated the growth of LNCaP prostate cancer cells in each of 14 separate experiments, producing an average increase in growth rate of over 30%. In contrast, almond milk suppressed the growth of these cells by over 30%. Neither cows' milk nor almond milk affected the growth of MCF-7 breast cancer cells or AsPC-1 pancreatic cancer cells significantly. Soy milk increased the growth rate of the breast cancer cells. These data indicate that prostate and breast cancer patients should be cautioned about the possible promotional effects of commercial dairy products and their substitutes.

  3. Characterising Castrate Tolerant Prostate Cancer Cells

    OpenAIRE

    ASHLEE KATE CLARK

    2017-01-01

    Prostate cancer is a prevalent disease in aging males. This thesis explores prostate cancer cells that escape current therapy and give rise to end-stage disease. Using sophisticated experimental approaches, this important cancer cell population was identified and characterised in human prostate cancer tissues.  Our discoveries will eventually lead to improved cancer treatments for men with prostate cancer.

  4. Enhancement of Cisplatin Sensitivity in Human Cervical Cancer: Epigallocatechin-3-Gallate

    Science.gov (United States)

    Kilic, Ulkan; Sahin, Kazim; Tuzcu, Mehmet; Basak, Nazli; Orhan, Cemal; Elibol-Can, Birsen; Kilic, Ertugrul; Sahin, Fikrettin; Kucuk, Omer

    2015-01-01

    Cisplatin is one of the effective chemotherapeutics in the treatment of several types of cancers. However, in addition to the efforts against to its toxicity, the amelioration of cisplatin sensitivity is an important point in treatment of cervical cancer. To do so, additional substances such as epigallocatechin gallate (EGCG), a polyphenol in green tea, have been used in combination with chemotherapeutics. We aimed to investigate the possible molecular pathways to potentiate cervical cancer cell (HeLa) growth inhibition by combination therapy of cisplatin and EGCG. HeLa cells were treated with EGCG (25 μM), cisplatin (250 nM), and their combination for 24 h. Cell viability was determined by MTS Assay. We analyzed the expressions of NF-κB p65, COX-2, Nrf2, HO-1, p-mTOR, p-p70S6K1, p-4E-BP1, and p-Akt by Western blot analysis. Herein, we have demonstrated that EGCG works synergistic with cisplatin in inhibiting growth of cervical cancer cells. EGCG improved efficacy of cisplatin treatment in HeLa cells by regulating NFκB p65, COX-2, p-Akt, and p-mTOR pathways, whereas it increased the expression levels of Nrf2/HO-1 in combined therapy. Our observations revealed that EGCG increases the sensitization of cisplatin to cervical cancer cells by inhibiting cell survival and inducing apoptosis. PMID:25988128

  5. Sensitive HPV detection in oropharyngeal cancers

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    Stanley Margaret A

    2009-12-01

    Full Text Available Abstract Background Human papillomaviruses (HPV are the aetiological agents of certain benign and malignant tumours of skin and mucosae; the most important of which is cervical cancer. Also, the incidence of ano-genital warts, HPV-anal cancer and oropharyngeal cancers are rising. To help ascertain a useful PCR detection protocol for oropharyngeal cancers, we directly compared three commonly used primer sets in detection of HPV from different clinical samples. Methods We compared PGMY09/11, MY09/11 and GP5+/6+ primers sets in PCRs of 34 clinically diagnosed samples of genital warts, cervical brushings (with associated histological diagnosis and vulval biopsies. All negative samples were subsequently tested using the previously reported PGMY/GP PCR method and amplicons directly sequenced for confirmation and typing. An optimised PCR protocol was then compared to a line blot assay for detection of HPV in 15 oropharyngeal cancer samples. Results PGMY09/11 primers detected HPV presence in more cervical brushing (100% and genital wart (92.9% samples compared to MY09/11 (90% and 64.3% and GP5+/6+ (80% and 64.3% primer sets, respectively. From vulval biopsies, HPV detection rates were: MY09/11 (63.6%, GP5+/6+ (54.5% and PGMY09/11 (54.5%. PGMY/GP nested PCR demonstrated that HPV was present, and direct sequencing confirmed genotypes. This nested PCR protocol showed detection of HPV in 10/15 (66.7% of oropharyngeal cancer samples. Conclusions PGMY09/11 primers are the preferred primer set among these three for primary PCR screening with different clinical samples. MY09/11 and GP5+/6+ may be used (particularly for cervical samples but demonstrate lower detection rates. A nested PCR approach (i.e. a PGMY-GP system may be required to confirm negativity or to detect low levels of HPV, undetectable using current primary PCR methods, as demonstrated using oropharyngeal cancer samples.

  6. ELF5 suppresses estrogen sensitivity and underpins the acquisition of antiestrogen resistance in luminal breast cancer.

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    Maria Kalyuga

    Full Text Available We have previously shown that during pregnancy the E-twenty-six (ETS transcription factor ELF5 directs the differentiation of mammary progenitor cells toward the estrogen receptor (ER-negative and milk producing cell lineage, raising the possibility that ELF5 may suppress the estrogen sensitivity of breast cancers. To test this we constructed inducible models of ELF5 expression in ER positive luminal breast cancer cells and interrogated them using transcript profiling and chromatin immunoprecipitation of DNA followed by DNA sequencing (ChIP-Seq. ELF5 suppressed ER and FOXA1 expression and broadly suppressed ER-driven patterns of gene expression including sets of genes distinguishing the luminal molecular subtype. Direct transcriptional targets of ELF5, which included FOXA1, EGFR, and MYC, accurately classified a large cohort of breast cancers into their intrinsic molecular subtypes, predicted ER status with high precision, and defined groups with differential prognosis. Knockdown of ELF5 in basal breast cancer cell lines suppressed basal patterns of gene expression and produced a shift in molecular subtype toward the claudin-low and normal-like groups. Luminal breast cancer cells that acquired resistance to the antiestrogen Tamoxifen showed greatly elevated levels of ELF5 and its transcriptional signature, and became dependent on ELF5 for proliferation, compared to the parental cells. Thus ELF5 provides a key transcriptional determinant of breast cancer molecular subtype by suppression of estrogen sensitivity in luminal breast cancer cells and promotion of basal characteristics in basal breast cancer cells, an action that may be utilised to acquire antiestrogen resistance.

  7. Inhibitory effect of Disulfiram/copper complex on non-small cell lung cancer cells

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    Duan, Lincan [Department of Thoracic Surgery, The Third Affiliated Hospital of Kunming Medical University, Kunming (China); Shen, Hongmei [Cancer Center of Integrative Medicine, The Third Affiliated Hospital of Kunming Medical University, Kunming (China); Zhao, Guangqiang [Department of Thoracic Surgery, The Third Affiliated Hospital of Kunming Medical University, Kunming (China); Yang, Runxiang [Cancer Chemotherapy Center, The Third Affiliated Hospital of Kunming Medical University, Kunming (China); Cai, Xinyi [Colorectal Cancer Center, The Third Affiliated Hospital of Kunming Medical University, Kunming (China); Zhang, Lijuan [Department of Pathology, The Third Affiliated Hospital of Kunming Medical University, Kunming (China); Jin, Congguo [Cancer Institute, The Third Affiliated Hospital of Kunming Medical University, Kunming (China); Huang, Yunchao, E-mail: daliduanlincan@163.com [Department of Thoracic Surgery, The Third Affiliated Hospital of Kunming Medical University, Kunming (China)

    2014-04-18

    Highlights: • Disulfiram and copper synergistically inhibit lung cancer cell proliferation. • Lung cancer cell colony formation ability is inhibited by Disulfiram/copper. • Disulfiram/copper increases the sensitivity of cisplatin to lung cancer cells. • Lung cancer stem cells are specifically targeted by Disulfiram/copper complex. - Abstract: Non-small cell lung cancer (NSCLC) is the most common cause of cancer-related death in both men and women worldwide. Recently, Disulfiram has been reported to be able to inhibit glioblastoma, prostate, or breast cancer cell proliferation. In this study, the synergistic effect of Disulfiram and copper on NSCLC cell growth was investigated. Inhibition of cancer cell proliferation was detected by 1-(4,5-Dimethylthiazol-2-yl)-3,5-diphenylformazan (MTT) assay and cell cycle analysis. Liquid colony formation and tumor spheroid formation assays were used to evaluate their effect on cancer cell clonogenicity. Real-time PCR was performed to test the mRNA level of cancer stem cell related genes. We found th