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Chen J, Ding Z, Peng Y, Pan F, Li J, Zou L, Zhang Y, Liang H. HIF-1α inhibition reverses multidrug resistance in colon cancer cells via downregulation of MDR1/P-glycoprotein. PLoS One 2014; 9:e98882. [PMID: 24901645 PMCID: PMC4047061 DOI: 10.1371/journal.pone.0098882] [Citation(s) in RCA: 99] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2013] [Accepted: 05/08/2014] [Indexed: 12/11/2022] Open
Abstract
Background Multidrug resistance (MDR) is one of the major reasons chemotherapy-based treatments fail. Hypoxia is generally associated with tumor chemoresistance. However, the correlation between the heterodimeric hypoxia-inducible factor-1 (HIF-1) and the multidrug resistance (MDR1) gene/transporter P-glycoprotein (P-gp) remains unclear. This study aims to explore the molecular mechanisms of reversing colon cancer MDR by focusing on the target gene HIF-1α. Methods A chemotherapeutic sensitivity assay was used to observe the efficiency of MDR reversal in LoVo multicellular spheroids (MCS). The apoptotic level induced by different drugs was examined by flow cytometry (FCM). Binding of HIF-1α to the MDR1 gene promoter was evaluated by Chromatin immunoprecipitation (ChIP). The relationship between HIF-1α/P-gp expression and sensitivity to chemotherapy was analyzed. Results The sensitivity of LoVo MCS to all four chemotherapy drugs was decreased to varying degrees under hypoxic conditions. After silencing the HIF-1α gene, the sensitivities of LoVo MCS to all four chemotherapy drugs were restored. The apoptotic levels that all the drugs induced were all decreased to various extents in the hypoxic group. After silencing HIF-1α, the apoptosis level induced by all four chemotherapy drugs increased. The expression of HIF-1α and P-gp was significantly enhanced in LoVo MCS after treatment with hypoxia. Inhibiting HIF-1α significantly decreased the expression of MDR1/P-gp mRNA or protein in both the LoVo monolayers and LoVo MCS. The ChIP assay showed that HIF-1α was bound to the MDR1 gene promoter. Advanced colon carcinoma patients with expression of both HIF-1α and P-gp were more resistant to chemotherapy than that with non expression. Conclusions HIF-1α inhibition reverses multidrug resistance in colon cancer cells via downregulation of MDR1/P-gp. The expression of HIF-1α and MDR1/P-gp can be used as a predictive marker for chemotherapy resistance in colon cancer.
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MESH Headings
- ATP Binding Cassette Transporter, Subfamily B/genetics
- Antineoplastic Agents/pharmacology
- Apoptosis/drug effects
- Apoptosis/genetics
- Cell Line, Tumor
- Colonic Neoplasms/genetics
- Colonic Neoplasms/metabolism
- Drug Resistance, Neoplasm/genetics
- Gene Expression Regulation, Neoplastic
- Humans
- Hypoxia/genetics
- Hypoxia/metabolism
- Hypoxia-Inducible Factor 1, alpha Subunit/genetics
- Hypoxia-Inducible Factor 1, alpha Subunit/metabolism
- Promoter Regions, Genetic
- Protein Binding
- RNA Interference
- RNA, Messenger/genetics
- RNA, Small Interfering/genetics
- Transcription, Genetic
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Affiliation(s)
- Jianfang Chen
- Department of Oncology and Southwest Cancer Center, Southwest Hospital, Third Military Medical University, Chongqing, China
| | - Zhenyu Ding
- Department of Oncology and Southwest Cancer Center, Southwest Hospital, Third Military Medical University, Chongqing, China
- Department of Oncology, General Hospital of Shenyang Military Region, Shenyang, Liaoning, China
| | - Yonghai Peng
- Department of Oncology and Southwest Cancer Center, Southwest Hospital, Third Military Medical University, Chongqing, China
| | - Feng Pan
- Department of Oncology and Southwest Cancer Center, Southwest Hospital, Third Military Medical University, Chongqing, China
| | - Jianjun Li
- Department of Oncology and Southwest Cancer Center, Southwest Hospital, Third Military Medical University, Chongqing, China
| | - Lan Zou
- Department of Oncology and Southwest Cancer Center, Southwest Hospital, Third Military Medical University, Chongqing, China
| | - Yanling Zhang
- Department of Oncology and Southwest Cancer Center, Southwest Hospital, Third Military Medical University, Chongqing, China
| | - Houjie Liang
- Department of Oncology and Southwest Cancer Center, Southwest Hospital, Third Military Medical University, Chongqing, China
- * E-mail:
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Xu F, Yang T, Fang D, Xu Q, Chen Y. An investigation of heat shock protein 27 and P-glycoprotein mediated multi-drug resistance in breast cancer using liquid chromatography-tandem mass spectrometry-based targeted proteomics. J Proteomics 2014; 108:188-97. [PMID: 24882106 DOI: 10.1016/j.jprot.2014.05.016] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2014] [Revised: 05/13/2014] [Accepted: 05/21/2014] [Indexed: 12/20/2022]
Abstract
UNLABELLED One missing puzzle piece to study heat shock protein 27 (HSP27) in P-glycoprotein (P-gp) mediated multi-drug resistance (MDR) was the amount of HSP27 and the extent of its phosphorylation in the biological context. Liquid chromatography-tandem mass spectrometry (LC/MS/MS)-based targeted proteomics allows researchers to monitor associated proteins and their modification simultaneously and quantitatively. In this study, a targeted proteomics assay was first developed and validated for the quantification of HSP27 and its phosphorylated forms. Using this assay, the level of HSP27 was determined in non-tumoral cells MCF-10A, parental drug-sensitive cancer cells MCF-7/WT and drug-resistant cancer cells MCF-7/ADR. A decrease of HSP27 expression was observed in P-gp overexpressed MCF-7/ADR cells. A quantitative time-course analysis of both HSP27 and P-gp in doxorubicin (DOX)-treated MCF-7/WT cells also implied that HSP27 may participate in the P-gp modulation. Furthermore, stoichiometry of site-specific HSP27 phosphorylation indicated that DOX treatment rapidly induced the HSP27 phosphorylation at Ser82. Moreover, conventional analytical methods were also performed for a comparison. BIOLOGICAL SIGNIFICANCE LC/MS/MS-based targeted proteomics turns out to be a promising quantification approach for the study of proteins in the preclinical and clinical environment. Unfortunately, rare studies applied this technology to detect multiple associated proteins or protein modification in one experiment. This study demonstrated the potential of LC/MS/MS-based targeted proteomics to understand the cell events in a more accurate context of biological system. By the quantitative time-course analysis of HSP27 and its phosphorylated forms at sites of Ser15 and Ser82, the possible role of HSP27 in P-gp mediated MDR was suggested. Further development of targeted proteomics in future may provide more insight into signal transduction pathways upon perturbation of a protein network or changes to a panel of proposed biomarkers in a given disease state.
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Affiliation(s)
- Feifei Xu
- School of Pharmacy, Nanjing Medical University, 818 Tian Yuan East Road, Nanjing 211166, China
| | - Ting Yang
- School of Pharmacy, Nanjing Medical University, 818 Tian Yuan East Road, Nanjing 211166, China
| | - Danjun Fang
- School of Pharmacy, Nanjing Medical University, 818 Tian Yuan East Road, Nanjing 211166, China
| | - Qingqing Xu
- School of Pharmacy, Nanjing Medical University, 818 Tian Yuan East Road, Nanjing 211166, China
| | - Yun Chen
- School of Pharmacy, Nanjing Medical University, 818 Tian Yuan East Road, Nanjing 211166, China.
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Abstract
Multidrug resistance (MDR) in cancer cells is a phenotype whereby cells display reduced sensitivity to anticancer drugs, based on a variety of mechanisms, including an increase in drug efflux, the reduction of drug uptake, the activation of cell growth and survival signaling, the promotion of DNA repair, and the inhibition of apoptosis signaling. Increased expression of the plasma membrane drug efflux pumps, the ATP-binding cassette (ABC) transporters, is involved in MDR. P-Glycoprotein/ABCB1 is a member of the ABC transporter family, and facilitates the efflux of various anticancer drugs, including anthracyclines, vinca alkaloids, epipodophyllotoxins, taxanes, and kinase inhibitors, from cells. P-Glycoprotein is also expressed in normal tissues and cells, including the kidney, liver, colon, and adrenal gland, to transport and/or secrete substrates and at the blood-brain, blood-placenta, and blood-testis barriers to protect these tissues from toxic substances. To understand the mechanistic functions of P-glycoprotein and to overcome MDR, investigators have identified the substrates and competitive inhibitors of P-glycoprotein. Recently, we and other groups reported associations between cellular signaling pathways and the expression, stability, degradation, localization, and activity of P-glycoprotein. The present review summarizes the currently available information about the transcriptional and posttranslational regulation of P-glycoprotein expression and function.
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Ma J, Yu L, Tian J, Mu Y, Lv Z, Zou J, Li J, Wang H, Xu W. MG132 reverse the malignant characteristics of hypopharyngeal cancer. Mol Med Rep 2014; 9:2587-91. [PMID: 24691740 DOI: 10.3892/mmr.2014.2103] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2013] [Accepted: 03/06/2014] [Indexed: 11/05/2022] Open
Abstract
In order to reverse the malignant characteristics of hypopharyngeal cancer, the proteasome inhibitor MG132 was introduced into FaDu/T cells and the mechanisms underlying its effects were investigated. The multi-drug resistance (MDR) sensitivities of FaDu/T and FaDu/T-MG132 cancer cells to several chemotherapeutics were investigated by a 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyltetrazolium bromide (MTT) assay. Apoptosis was measured by staining cells with Annexin V and propidium iodide (PI) double staining. Reverse transcription-polymerase chain reaction and western blot analysis were conducted to detect mRNA and corresponding protein levels of the MDR- and apoptosis-related genes P-glycoprotein (P-gp), caspase-3, Bcl-2 and Bax. The nuclear protein of nuclear factor κ-light-chain-enhancer of activated B cells. (NF-κB) and p53 were also investigated via western blot analysis. Compared with FaDu/T cells, the drug resistance of FaDu/T + MG132 cells to cisplatin (DDP), 5-fluorouracil (5-FU), doxorubicin (Dox) and vincristine (VCR) decreased. With increased expression of caspase-3 and Bax and decreased expression of Bcl-2, the anti-apoptotic ability markedly decreased in FaDu/T + MG132 cells. P-gp and NF-κB significantly decreased; however, p53 increased in FaDu/T + MG132 cells. These results suggested that the proteasome inhibitor MG132 reversed the malignant characteristics of FaDu/T by enhancing apoptosis and inhibiting P-gp. MG132 was also able to inhibit the nuclear translocation of NF-κB and increase the expression of p53.
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Affiliation(s)
- Juke Ma
- Department of Otolaryngology-Head and Neck Surgery, Provincial Hospital Affiliated to Shandong University, Jinan, Shandong 250021, P.R. China
| | - Liang Yu
- Department of Otolaryngology-Head and Neck Surgery, Provincial Hospital Affiliated to Shandong University, Jinan, Shandong 250021, P.R. China
| | - Jiajun Tian
- Department of Otolaryngology-Head and Neck Surgery, Provincial Hospital Affiliated to Shandong University, Jinan, Shandong 250021, P.R. China
| | - Yakui Mu
- Department of Otolaryngology-Head and Neck Surgery, Provincial Hospital Affiliated to Shandong University, Jinan, Shandong 250021, P.R. China
| | - Zhenghua Lv
- Department of Otolaryngology-Head and Neck Surgery, Provincial Hospital Affiliated to Shandong University, Jinan, Shandong 250021, P.R. China
| | - Jidong Zou
- Department of Otolaryngology-Head and Neck Surgery, Provincial Hospital Affiliated to Shandong University, Jinan, Shandong 250021, P.R. China
| | - Jianfeng Li
- Institute of Eye and Otolaryngology, Shandong Clinic Research Institute, Jinan, Shandong 250022, P.R. China
| | - Haibo Wang
- Department of Otolaryngology-Head and Neck Surgery, Provincial Hospital Affiliated to Shandong University, Jinan, Shandong 250021, P.R. China
| | - Wei Xu
- Department of Otolaryngology-Head and Neck Surgery, Provincial Hospital Affiliated to Shandong University, Jinan, Shandong 250021, P.R. China
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Zhao BX, Sun YB, Wang SQ, Duan L, Huo QL, Ren F, Li GF. Grape seed procyanidin reversal of p-glycoprotein associated multi-drug resistance via down-regulation of NF-κB and MAPK/ERK mediated YB-1 activity in A2780/T cells. PLoS One 2013; 8:e71071. [PMID: 23967153 PMCID: PMC3744527 DOI: 10.1371/journal.pone.0071071] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2013] [Accepted: 07/01/2013] [Indexed: 11/20/2022] Open
Abstract
The expression and function of P-glycoprotein (P-gp) is associated with the phenotype of multi-drug resistance (MDR), leading chemotherapy failure of patients suffered with cancer. Grape seed procyanidin(GSP) is a natural polyphenol supplement with anti-inflammatory effect. Present study assessed a new use of GSP on the MDR reversal activity and its possible molecular mechanisms in MDR1-overpressing paclitaxel resistant ovarian cancer cells. Our results showed GSP significantly enhanced the cytotoxicity of paclitaxel and adriamycin in paclitaxel resistant A2780/T cells but its parental A2780 cells. Furthermore, GSP strongly inhibited P-gp expression by blocking MDR1 gene transcription, as well as, increased the intracellular accumulation of the P-gp substrate rhodamine-123 in A2780/T cells. Nuclear factor-κB(NF-κB) activity, IκB degradation level and NF-κB/p65 nuclear translocation induced by lipopolysaccharide (LPS) and receptor activator for nuclear factor-κB ligand (RANKL) were markedly inhibited by pre-treatment with GSP. Meanwhile, GSP inhibited MAPK/ERK pathway by decreasing the phosphorylation of ERK1/2, resulting in reduced the Y-box binding protein 1 (YB-1) activation with blocking its nuclear translocation. Moreover, the up-regulation of P-gp expression, the activation of AKT/NF-κB and MAPK/ERK pathway induced by LPS was attenuated by GSP administration. Compared with PDTC and U1026, inhibitor of NF-κB and MAPK/ERK respectively, GSP showed the same tendency of down-regulating NF-κB and MAPK/ERK mediated YB-1 activities. Thus, GSP reverses P-gp associated MDR by inhibiting the function and expression of P-gp through down-regulation of NF-κB activity and MAPK/ERK pathway mediated YB-1 nuclear translocation, offering insight into the mechanism of reversing MDR by natural polyphenol supplement compounds. GSP could be a new potential MDR reversal agent used for combination therapy with chemotherapeutics in clinic.
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Affiliation(s)
- Bo-xin Zhao
- Department of Pharmacy, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China
| | - Ya-bin Sun
- GCP Office, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China
| | - Sheng-qi Wang
- Department of Pharmacy, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China
| | - Lian Duan
- Department of Pharmacy, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China
| | - Qi-lu Huo
- Department of Pharmacy, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China
| | - Fei Ren
- Department of Pharmacy, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China
| | - Guo-feng Li
- Department of Pharmacy, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China
- * E-mail:
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56
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Li HH, Su JH, Chiu CC, Lin JJ, Yang ZY, Hwang WI, Chen YK, Lo YH, Wu YJ. Proteomic investigation of the sinulariolide-treated melanoma cells A375: effects on the cell apoptosis through mitochondrial-related pathway and activation of caspase cascade. Mar Drugs 2013; 11:2625-42. [PMID: 23880933 PMCID: PMC3736442 DOI: 10.3390/md11072625] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2013] [Revised: 07/09/2013] [Accepted: 07/10/2013] [Indexed: 12/22/2022] Open
Abstract
Sinulariolide is an active compound isolated from the cultured soft coral Sinularia flexibilis. In this study, we investigated the effects of sinulariolide on A375 melanoma cell growth and protein expression. Sinulariolide suppressed the proliferation and migration of melanoma cells in a concentration-dependent manner and was found to induce both early and late apoptosis by flow cytometric analysis. Comparative proteomic analysis was conducted to investigate the effects of sinulariolide at the molecular level by comparison between the protein profiles of melanoma cells treated with sinulariolide and those without treatment. Two-dimensional gel electrophoresis (2-DE) master maps of control and treated A375 cells were generated by analysis with PDQuest software. Comparison between these maps showed up- and downregulation of 21 proteins, seven of which were upregulated and 14 were downregulated. The proteomics studies described here identify some proteins that are involved in mitochondrial dysfunction and apoptosis-associated proteins, including heat shock protein 60, heat shock protein beta-1, ubiquinol cytochrome c reductase complex core protein 1, isocitrate dehydrogenase (NAD) subunit alpha (down-regulated), and prohibitin (up-regulated), in A375 melanoma cells exposed to sinulariolide. Sinulariolide-induced apoptosis is relevant to mitochondrial-mediated apoptosis via caspase-dependent pathways, elucidated by the loss of mitochondrial membrane potential, release of cytochrome c, and activation of Bax, Bad and caspase-3/-9, as well as suppression of p-Bad, Bcl-xL and Bcl-2. Taken together, our results show that sinulariolide-induced apoptosis might be related to activation of the caspase cascade and mitochondria dysfunction pathways. Our results suggest that sinulariolide merits further evaluation as a chemotherapeutic agent for human melanoma.
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Affiliation(s)
- Hsing-Hui Li
- National Museum of Marine Biology and Aquarium, Pingtung 94450, Taiwan; E-Mails: (H.-H.L.); (J.-H.S.)
| | - Jui-Hsin Su
- National Museum of Marine Biology and Aquarium, Pingtung 94450, Taiwan; E-Mails: (H.-H.L.); (J.-H.S.)
| | - Chien-Chih Chiu
- Department of Biotechnology, Kaohsiung Medical University, Kaohsiung 80761, Taiwan; E-Mail:
| | - Jen-Jie Lin
- Graduate Institute of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung 91202, Taiwan; E-Mail:
| | - Zih-Yan Yang
- Graduate Institute of Food Science, National Pingtung University of Science and Technology, Pingtung 91202, Taiwan; E-Mail:
| | - Wen-Ing Hwang
- Department of Food Science and Nutrition, Meiho University, Pingtung 91202, Taiwan; E-Mails: (W.-I.H.); (Y.-K.C.)
| | - Yu-Kuei Chen
- Department of Food Science and Nutrition, Meiho University, Pingtung 91202, Taiwan; E-Mails: (W.-I.H.); (Y.-K.C.)
| | - Yu-Hsuan Lo
- Excellence Biotech Co., Kaohsiung 80655, Taiwan; E-Mail:
| | - Yu-Jen Wu
- Department of Biotechnology, Kaohsiung Medical University, Kaohsiung 80761, Taiwan; E-Mail:
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +886-8-7799821 (ext. 8613); Fax: +886-8-7797821
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57
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Parthenolide reverses doxorubicin resistance in human lung carcinoma A549 cells by attenuating NF-κB activation and HSP70 up-regulation. Toxicol Lett 2013; 221:73-82. [PMID: 23792430 DOI: 10.1016/j.toxlet.2013.06.215] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2013] [Revised: 06/10/2013] [Accepted: 06/12/2013] [Indexed: 11/23/2022]
Abstract
Chemotherapy resistance represents a major problem for the treatment of patients with lung carcinomas. Parthenolide (PN), a naturally occurring small molecule found in herb feverfew, has been used in clinical treatment. Although its importance in treating the chemotherapy resistance has been shown, the pharmacological benefits of PN for lung cancer with multidrug resistance are underappreciated. Using human lung epithelial carcinoma A549 and A549 derived DOX-resistant A549/DOX cell lines, we found that PN enhanced the apoptotic cytotoxicity of DOX in A549/DOX cells. PN inhibited P-glycoprotein (P-gp) up-regulation and promoted the intracellular accumulation of DOX in A549/DOX cells. PN also exhibited inhibitory effect on NF-κB activation in A549/DOX cells, suggesting that inhibition of NF-κB was involved in attenuating P-gp expression by PN. Moreover, we found that PN could also effectively inhibit the HSP70 up-regulation in A549/DOX cells. Further studies revealed a positive correlation between HSP70 and P-gp expression. Overexpression of HSP70 upregulated P-gp expression independently of NF-κB activation in A549 cells, and knockdown of HSP70 caused a reduced expression of P-gp in A549/DOX cells. RT-PCR experiments showed that HSP70 modulated the P-gp expression mainly at transcription level. Taken together, PN can reverse DOX resistance through suppressing P-gp expression by mechanisms involving attenuation of NF-κB activation and HSP70 up-regulation. Our results not only provide insight into potential use of PN in reversing P-gp mediated MDR to facilitate lung cancer chemotherapy, but also highlight a potential role of HSP70 in the development of drug resistance.
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58
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Katayama K, Noguchi K, Sugimoto Y. FBXO15 regulates P-glycoprotein/ABCB1 expression through the ubiquitin--proteasome pathway in cancer cells. Cancer Sci 2013; 104:694-702. [PMID: 23465077 DOI: 10.1111/cas.12145] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2012] [Revised: 02/27/2013] [Accepted: 03/01/2013] [Indexed: 12/25/2022] Open
Abstract
Expression of P-glycoprotein (P-gp)/ABCB1 on cancer cell surfaces is a critical determinant of anticancer drug resistance. Regulators of P-gp expression and function are key molecules controlling drug resistance. Here we report the mechanism underlying the ubiquitin-proteasome pathway-mediated degradation of P-gp. The proteasome inhibitor MG132 increased the P-gp level, enhanced its ubiquitination, and delayed the disappearance of the ubiquitinated P-gp. To search for regulators of P-gp ubiquitination, MALDI-time of flight mass spectrometry analyses were carried out, and 22 candidates were identified as P-gp binding partners. Among them, FBXO15/Fbx15 is known as an F-box protein in the ubiquitin E3 ligase complex, Skp1-Cullin1-FBXO15 (SCF(Fbx15) ); therefore, we further studied the involvement of FBXO15 on P-gp degradation. Coprecipitation assays revealed that FBXO15 bound to P-gp. We screened ubiquitin-conjugating enzyme E2s that bind to FBXO15 and P-gp; Ube2r1/Cdc34/Ubc3 was found to be a binding partner. Exogenous FBXO15 expression enhanced P-gp ubiquitination, but FBXO15 knockdown suppressed it. FBXO15 knockdown increased P-gp expression without affecting its mRNA level. Ube2r1 knockdown decreased P-gp ubiquitination, and simultaneous knockdown of Ube2r1 with FBXO15 further suppressed the ubiquitination. Ube2r1 knockdown increased P-gp expression, suggesting that Ube2r1 is a partner of FBXO15 in P-gp ubiquitination. FBXO15 knockdown enhanced vincristine resistance and lowered intracellular levels of rhodamine 123. These data suggest that FBXO15 and Ube2r1 regulate P-gp expression through the ubiquitin-proteasome pathway.
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Affiliation(s)
- Kazuhiro Katayama
- Division of Chemotherapy, Faculty of Pharmacy, Keio University, Tokyo, Japan
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59
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Sims JT, Ganguly SS, Bennett H, Friend JW, Tepe J, Plattner R. Imatinib reverses doxorubicin resistance by affecting activation of STAT3-dependent NF-κB and HSP27/p38/AKT pathways and by inhibiting ABCB1. PLoS One 2013; 8:e55509. [PMID: 23383209 PMCID: PMC3561297 DOI: 10.1371/journal.pone.0055509] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2012] [Accepted: 12/23/2012] [Indexed: 02/07/2023] Open
Abstract
Despite advances in cancer detection and prevention, a diagnosis of metastatic disease remains a death sentence due to the fact that many cancers are either resistant to chemotherapy (conventional or targeted) or develop resistance during treatment, and residual chemoresistant cells are highly metastatic. Metastatic cancer cells resist the effects of chemotherapeutic agents by upregulating drug transporters, which efflux the drugs, and by activating proliferation and survival signaling pathways. Previously, we found that c-Abl and Arg non-receptor tyrosine kinases are activated in breast cancer, melanoma, and glioblastoma cells, and promote cancer progression. In this report, we demonstrate that the c-Abl/Arg inhibitor, imatinib (imatinib mesylate, STI571, Gleevec), reverses intrinsic and acquired resistance to the anthracycline, doxorubicin, by inducing G2/M arrest and promoting apoptosis in cancer cells expressing highly active c-Abl and Arg. Significantly, imatinib prevents intrinsic resistance by promoting doxorubicin-mediated NF-κB/p65 nuclear localization and repression of NF-κB targets in a STAT3-dependent manner, and by preventing activation of a novel STAT3/HSP27/p38/Akt survival pathway. In contrast, imatinib prevents acquired resistance by inhibiting upregulation of the ABC drug transporter, ABCB1, directly inhibiting ABCB1 function, and abrogating survival signaling. Thus, imatinib inhibits multiple novel chemoresistance pathways, which indicates that it may be effective in reversing intrinsic and acquired resistance in cancers containing highly active c-Abl and Arg, a critical step in effectively treating metastatic disease. Furthermore, since imatinib converts a master survival regulator, NF-κB, from a pro-survival into a pro-apoptotic factor, our data suggest that NF-κB inhibitors may be ineffective in sensitizing tumors containing activated c-Abl/Arg to anthracyclines, and instead might antagonize anthracycline-induced apoptosis.
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Affiliation(s)
- Jonathan T. Sims
- Department of Molecular and Biomedical Pharmacology, University of Kentucky School of Medicine, Lexington, Kentucky, United States of America
| | - Sourik S. Ganguly
- Department of Molecular and Biomedical Pharmacology, University of Kentucky School of Medicine, Lexington, Kentucky, United States of America
| | - Holly Bennett
- Department of Molecular and Biomedical Pharmacology, University of Kentucky School of Medicine, Lexington, Kentucky, United States of America
| | - J. Woodrow Friend
- Department of Molecular and Biomedical Pharmacology, University of Kentucky School of Medicine, Lexington, Kentucky, United States of America
| | - Jessica Tepe
- Department of Molecular and Biomedical Pharmacology, University of Kentucky School of Medicine, Lexington, Kentucky, United States of America
| | - Rina Plattner
- Department of Molecular and Biomedical Pharmacology, University of Kentucky School of Medicine, Lexington, Kentucky, United States of America
- * E-mail:
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60
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Xu Y, Diao Y, Qi S, Pan X, Wang Q, Xin Y, Cao X, Ruan J, Zhao Z, Luo L, Liu C, Yin Z. Phosphorylated Hsp27 activates ATM-dependent p53 signaling and mediates the resistance of MCF-7 cells to doxorubicin-induced apoptosis. Cell Signal 2013; 25:1176-85. [PMID: 23357534 DOI: 10.1016/j.cellsig.2013.01.017] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2012] [Revised: 12/30/2012] [Accepted: 01/21/2013] [Indexed: 01/07/2023]
Abstract
DNA damage activates p53 and its downstream target genes, which further leads to apoptosis or survival either by the cell cycle arrest or by DNA repair. In many tumors, the heat shock protein 27 (Hsp27) is expressed at high levels to provide protection against anticancer drugs. However, the roles of Hsp27 in p53-mediated cellular responses to DNA damage are controversial. Here, we investigated the interplay between the phosphorylation status of Hsp27 and p53 in kidney 293A (HEK293A) cells and found that over-expressing phosphorylated Hsp27 mimics (Hsp27-3D) activated p53/p21 in an ATM-dependent manner. In addition, incubation with doxorubicin (Dox), an anticancer drug, induced Hsp27 phosphorylation in human adenocarcinoma cells (MCF-7). In contrast, inhibition of Hsp27 phosphorylation retarded both p53 induction and p21 accumulation, and led to cell apoptosis. Furthermore, phosphorylated Hsp27 increased p53 nuclear importing and its downstream target gene expression such as p21 and MDM2, while de-phosphorylated Hsp27 impeded this procession. Taken together, our data suggest that Hsp27, in its phosphorylated or de-phosphorylated status, plays different roles in regulating p53 pathway and cell survival.
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Affiliation(s)
- Yimiao Xu
- Jiangsu Province Key Laboratory for Molecular and Medicine Biotechnology, College of Life Science, Nanjing Normal University, Nanjing, Jiangsu, PR China
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Schäfer C, Seeliger H, Bader DC, Assmann G, Buchner D, Guo Y, Ziesch A, Palagyi A, Ochs S, Laubender RP, Jung A, De Toni EN, Kirchner T, Göke B, Bruns C, Gallmeier E. Heat shock protein 27 as a prognostic and predictive biomarker in pancreatic ductal adenocarcinoma. J Cell Mol Med 2012; 16:1776-91. [PMID: 22004109 PMCID: PMC3822691 DOI: 10.1111/j.1582-4934.2011.01473.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
A role of heat shock protein 27 (HSP27) as a potential biomarker has been reported in various tumour entities, but comprehensive studies in pancreatic cancer are lacking. Applying tissue microarray (TMA) analysis, we correlated HSP27 protein expression status with clinicopathologic parameters in pancreatic ductal adenocarcinoma specimens from 86 patients. Complementary, we established HSP27 overexpression and RNA-interference models to assess the impact of HSP27 on chemo- and radiosensitivity directly in pancreatic cancer cells. In the TMA study, HSP27 expression was found in 49% of tumour samples. Applying univariate analyses, a significant correlation was found between HSP27 expression and survival. In the multivariate Cox-regression model, HSP27 expression emerged as an independent prognostic factor. HSP27 expression also correlated inversely with nuclear p53 accumulation, indicating either protein interactions between HSP27 and p53 or TP53 mutation-dependent HSP27-regulation in pancreatic cancer. In the sensitivity studies, HSP27 overexpression rendered HSP27 low-expressing PL5 pancreatic cancer cells more susceptible towards treatment with gemcitabine. Vice versa, HSP27 protein depletion in HSP27 high-expressing AsPC-1 cells caused increased gemcitabine resistance. Importantly, HSP27 expression was inducible in pancreatic cancer cell lines as well as primary cells. Taken together, our study suggests a role for HSP27 as a prognostic and predictive marker in pancreatic cancer. Assessment of HSP27 expression could thus facilitate the identification of specific patient subpopulations that might benefit from individualized treatment options. Additional studies need to clarify whether modulation of HSP27 expression could represent an attractive concept to support the incorporation of hyperthermia in clinical treatment protocols for pancreatic cancer.
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Affiliation(s)
- Claus Schäfer
- Department of Medicine II, Klinikum Neumarkt, Neumarkt id OPf, Germany
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Li Y, Zhao L, Sun H, Yu J, Li N, Liang J, Wang Y, He M, Bai X, Yu Z, Zheng Z, Mi X, Wang E, Wei M. Gene silencing of FANCF potentiates the sensitivity to mitoxantrone through activation of JNK and p38 signal pathways in breast cancer cells. PLoS One 2012; 7:e44254. [PMID: 22952942 PMCID: PMC3429446 DOI: 10.1371/journal.pone.0044254] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2012] [Accepted: 07/31/2012] [Indexed: 12/21/2022] Open
Abstract
Fanconi anemia complementation group-F (FANCF) is a key factor to maintain the function of FA/BRCA, a DNA-damage response pathway. However, the functional role of FANCF in breast cancer has not been elucidated. In this study, we examined the effects and mechanisms of FANCF-RNAi on the sensitivity of breast cancer cells to mitoxantrone (MX). FANCF silencing by FANCF-shRNA blocked functions of FA/BRCA pathway through inhibition of FANCD2 mono-ubiquitination in breast cancer cell lines MCF-7 and T-47D. In addition, FANCF shRNA inhibited cell proliferation, induced apoptosis, and chromosome fragmentation in both breast cancer cells. We also found that FANCF silencing potentiated the sensitivity to MX in breast cancer cells, accompanying with an increase in intracellular MX accumulation and a decrease in BCRP expression. Furthermore, we found that the blockade of FA/BRCA pathway by FANCF-RNAi activated p38 and JNK MAPK signal pathways in response to MX treatment. BCRP expression was restored by p38 inhibitor SB203580, but not by JNK inhibitor SP600125. FANCF silencing increased JNK and p38 mediated activation of p53 in MX-treated breast cancer cells, activated the mitochondrial apoptosis pathway. Our findings indicate that FANCF shRNA potentiates the sensitivity of breast cancer cells to MX, suggesting that FANCF may be a potential target for therapeutic strategies for the treatment of breast tumors.
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Affiliation(s)
- Yanlin Li
- Department of Pharmacology, China Medical University, Shenyang City, Liaoning, China
| | - Lin Zhao
- Department of Pharmacology, China Medical University, Shenyang City, Liaoning, China
| | - Haigang Sun
- Department of Pharmacology, China Medical University, Shenyang City, Liaoning, China
| | - Jiankun Yu
- Department of Pharmacology, China Medical University, Shenyang City, Liaoning, China
| | - Na Li
- Department of Pharmacology, China Medical University, Shenyang City, Liaoning, China
| | - Jingwei Liang
- Department of Pharmacology, China Medical University, Shenyang City, Liaoning, China
| | - Yan Wang
- Department of Pharmacology, China Medical University, Shenyang City, Liaoning, China
| | - Miao He
- Department of Pharmacology, China Medical University, Shenyang City, Liaoning, China
| | - Xuefeng Bai
- Department of Pharmacology, China Medical University, Shenyang City, Liaoning, China
| | - Zhaojin Yu
- Department of Pharmacology, China Medical University, Shenyang City, Liaoning, China
| | - Zhihong Zheng
- Institute of Pathophysiology, China Medical University, Shenyang City, Liaoning, China
| | - Xiaoyi Mi
- Institute of Pathophysiology, China Medical University, Shenyang City, Liaoning, China
| | - Enhua Wang
- Institute of Pathophysiology, China Medical University, Shenyang City, Liaoning, China
| | - Minjie Wei
- Department of Pharmacology, China Medical University, Shenyang City, Liaoning, China
- Institute of Pathophysiology, China Medical University, Shenyang City, Liaoning, China
- * E-mail:
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63
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Su TR, Lin JJ, Chiu CC, Chen JYF, Su JH, Cheng ZJ, Hwang WI, Huang HH, Wu YJ. Proteomic investigation of anti-tumor activities exerted by sinularin against A2058 melanoma cells. Electrophoresis 2012; 33:1139-52. [PMID: 22539317 DOI: 10.1002/elps.201100462] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The extracts from soft corals have been increasingly investigated for biomedical and therapeutic purposes. The aim of this study is to examine and analyze the anti-tumor effects of the genus Sinularia extract sinularin on A2058 melanoma cells using MTT assay, cell migration assay, wound healing assay, flow cytometric analysis, and proteomic analysis. Sinularin dose-dependently (1-5 μg/mL) inhibited melanoma cell proliferation while the treatment at identical concentrations suppressed cell migration. Sinularin dose-dependently enhanced apoptotic melanoma cells and caused tumor cell accumulation at G2/M phase, indicating that sinularin exerts apoptosis-induced and cell cycle-delayed activities in A2058 melanoma cells. Comparative proteomic analysis was conducted to investigate the effects of sinularin at the molecular level by comparison between the protein profiling of melanoma cells treated with sinularin and without the treatment. Thirty-five differential proteins (13 upregulated and 22 downregulated) concerning the treatment were identified by liquid chromatography-tandem mass spectrometry. Proteomic data and Western blot displayed the levels of several tumor inhibitory or apoptosis-associated proteins including annexin A1, voltage-dependent anion-selective channel protein 1 and prohibitin (upregulated), heat shock protein 60, heat shock protein beta-1, and peroxiredoxin-2 (downregulated) in A2058 melanoma cells exposed to sinularin. Increased expression of p53, cleaved-caspase-3, cleaved-caspase-8, cleaved-caspase-9, p21, and Bax and decreased expression of Bcl-2 in sinularin-treated melanoma cells suggest that the anti-tumor activities of sinularin against melanoma cells are particularly correlated with these pro-apoptotic factors. These data provide important information for the mechanisms of anti-tumor effects of sinularin on melanoma cells and may be helpful for drug development and progression monitoring of human melanoma.
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Affiliation(s)
- Tzu-Rong Su
- Antai Tian-Sheng Memorial Hospital, Pingtung, Taiwan
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64
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Fang P, Zhang X, Gao Y, Ding CR, Cui F, Jiao SC. Reversal effect of melanoma differentiation associated gene-7/interleukin-24 on multidrug resistance in human hepatocellular carcinoma cells. Anat Rec (Hoboken) 2012; 295:1639-46. [PMID: 22899557 DOI: 10.1002/ar.22551] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2011] [Accepted: 07/20/2012] [Indexed: 12/13/2022]
Abstract
Multidrug resistance is the main cause for failure of chemotherapy. Melanoma differentiation associated gene-7/interleukin-24 (mda-7/IL-24) has been implicated in the inhibition of human tumor cell proliferation. However, the reversing effect of mda-7/IL-24 on multidrug resistance of human hepatocellular carcinoma (HCC) is not fully clear. In this study, we investigated the effects of overexpression of the mda-7/IL-24 gene in human HCC. We established mda-7/IL-24 overexpressing BEL-7402/5-fluorouracil (5-FU) cell lines and their drug sensitivity to 5-FU and doxorubicin (DOX) which were investigated by MTT. Furthermore, we investigated the apoptotic rate and the intracellular accumulation of Rhodamine-123 and DOX by flow cytometry. We also studied the expression of multidrug resistance gene 1 (MDR1), lung resistance-related protein (LRP), and multidrug resistance-related protein 1 (MRP1) by real-time polymerase chain reaction and Western blotting. Transcriptional activation of AP-1 and NF-κB was determined by luciferase reporter assay. The drug sensitivity of 5-FU or DOX, the apoptotic rate, and the intracellular accumulation of Rhodamine-123 and DOX were increased, while the mRNA and protein expression levels of MDR1, LRP, and MRP1 were reduced. The transcriptional activation of AP-1 and NF-κB was suppressed in mda-7/IL-24 overexpressing BEL-7402/5-FU cells. Our results demonstrated that mda-7/IL-24 could restore the drug sensitivity through the downregulation of MDR1, MRP1, and LRP expression, as well as the transcriptional activation of AP-1 and NF-κB and effectively reverse MDR.
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Affiliation(s)
- Ping Fang
- Institute of Cancer, PLA General Hospital, Beijing, China
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65
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Ciocca DR, Arrigo AP, Calderwood SK. Heat shock proteins and heat shock factor 1 in carcinogenesis and tumor development: an update. Arch Toxicol 2012; 87:19-48. [PMID: 22885793 DOI: 10.1007/s00204-012-0918-z] [Citation(s) in RCA: 194] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2012] [Accepted: 07/25/2012] [Indexed: 12/20/2022]
Abstract
Heat shock proteins (HSP) are a subset of the molecular chaperones, best known for their rapid and abundant induction by stress. HSP genes are activated at the transcriptional level by heat shock transcription factor 1 (HSF1). During the progression of many types of cancer, this heat shock transcriptional regulon becomes co-opted by mechanisms that are currently unclear, although evidently triggered in the emerging tumor cell. Concerted activation of HSF1 and the accumulation of HSPs then participate in many of the traits that permit the malignant phenotype. Thus, cancers of many histologies exhibit activated HSF1 and increased HSP levels that may help to deter tumor suppression and evade therapy in the clinic. We review here the extensive work that has been carried out and is still in progress aimed at (1) understanding the oncogenic mechanisms by which HSP genes are switched on, (2) determining the roles of HSF1/HSP in malignant transformation and (3) discovering approaches to therapy based on disrupting the influence of the HSF1-controlled transcriptome in cancer.
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Affiliation(s)
- Daniel R Ciocca
- Oncology Laboratory, Institute of Experimental Medicine and Biology of Cuyo (IMBECU), Scientific and Technological Center (CCT), CONICET, 5500 Mendoza, Argentina.
| | - Andre Patrick Arrigo
- Apoptosis Cancer and Development, Cancer Research Center of Lyon (CRCL), UMR INSERM 1052-CNRS 5286, Claude Bernard University, Lyon-1, Cheney A Building, Centre Regional Léon Bérard, 28, rue Laennec 69008 LYON, France. ;
| | - Stuart K Calderwood
- Molecular and Cellular Radiation Oncology, Department of Radiation Oncology, Beth Israel Deaconess Medical Center, Boston, MA02215
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Krishnamurthy K, Vedam K, Kanagasabai R, Druhan LJ, Ilangovan G. Heat shock factor-1 knockout induces multidrug resistance gene, MDR1b, and enhances P-glycoprotein (ABCB1)-based drug extrusion in the heart. Proc Natl Acad Sci U S A 2012; 109:9023-8. [PMID: 22615365 PMCID: PMC3384141 DOI: 10.1073/pnas.1200731109] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Heat-shock factor 1 (HSF-1), a transcription factor for heat-shock proteins (HSPs), is known to interfere with the transcriptional activity of many oncogenic factors. In the present work, we have discovered that HSF-1 ablation induced the multidrug resistance gene, MDR1b, in the heart and increased the expression of P-glycoprotein (P-gp, ABCB1), an ATP binding cassette that is usually associated with multidrug-resistant cancer cells. The increase in P-gp enhanced the extrusion of doxorubicin (Dox) to alleviate Dox-induced heart failure and reduce mortality in mice. Dox-induced left ventricular (LV) dysfunction was significantly reduced in HSF-1(-/-) mice. DNA-binding activity of NF-κB was higher in HSF-1(-/-) mice. IκB, the NF-κB inhibitor, was depleted due to enhanced IκB kinase (IKK)-α activity. In parallel, MDR1b gene expression and a large increase in P-gp and lowering Dox loading were observed in HSF-1(-/-) mouse hearts. Moreover, application of the P-gp antagonist, verapamil, increased Dox loading in HSF-1(-/-) cardiomyocytes, deteriorated cardiac function in HSF-1(-/-) mice, and decreased survival. MDR1 promoter activity was higher in HSF-1(-/-) cardiomyocytes, whereas a mutant MDR1 promoter with heat-shock element (HSE) mutation showed increased activity only in HSF-1(+/+) cardiomyocytes. However, deletion of HSE and NF-κB binding sites diminished luminescence in both HSF-1(+/+) and HSF-1(-/-) cardiomyocytes, suggesting that HSF-1 inhibits MDR1 activity in the heart. Thus, because high levels of HSF-1 are attributed to poor prognosis of cancer, systemic down-regulation of HSF-1 before chemotherapy is a potential therapeutic approach to ameliorate the chemotherapy-induced cardiotoxicity and enhance cancer prognosis.
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Affiliation(s)
| | | | | | - Lawrence J. Druhan
- Anesthesiology, Division of Cardiovascular Medicine, Davis Heart and Lung Research Institute, The Ohio State University, Columbus, OH 43210
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ABCB1/MDR1 contributes to the anticancer drug-resistant phenotype of IPH-926 human lobular breast cancer cells. Cancer Lett 2011; 315:153-60. [PMID: 22118813 DOI: 10.1016/j.canlet.2011.09.038] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2011] [Revised: 09/22/2011] [Accepted: 09/27/2011] [Indexed: 11/21/2022]
Abstract
Contribution of the ABCB1/MDR1/P-glycoprotein drug transporter to breast cancer resistance has been controversial. One issue is that ABCB1-dependent drug-resistance has primarily been investigated in mammary epithelial cell models technically manipulated to overexpress ABCB1, either by gene transfer using appropriate expression vectors or by chronic anticancer drug-selection. However, an unmodified human breast cancer cell line with an endogenous overexpression of ABCB1 has not been described thus far. Using Affymetrix microarray analyses, we identified an endogenous overexpression of several tumor-biologically relevant transcripts including ABCB1, BCAR4, CCL28, SCGB2A2 and PIP in IPH-926, an anticancer drug-resistant human lobular breast cancer cell line derived from a chemo-refractory mammary carcinoma patient. In a panel of twenty breast cancer cell lines examined, overexpression of ABCB1 mRNA and protein was exclusively detected in IPH-926. This was further validated using chronically in vitro drug-selected KB-V-1 cells as a widely used reference model to accurately define an ABCB1 overexpression. IPH-926 and KB-V-1 displayed a similar overexpression of ABCB1. Flow cytometric analyses showed that IPH-926 but not ABCB1-negative breast cancer cells extruded the anticancer agent doxorubicin, a classical substrate of the ABCB1 drug transporter. PSC-833 (valspodar), a selective ABCB1 inhibitor, blocked this efflux, restored apoptotic PARP cleavage and increased doxorubicin sensitivity in IPH-926 and KB-V-1. To our knowledge, IPH-926 represents the first human breast cancer cell line with a genuine, endogenous overexpression of ABCB1. IPH-926 provides evidence that ABCB1 can occasionally cause anticancer drug-resistance in breast cancer patients and offers a new tool for the evaluation of compounds to overcome drug-resistance.
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