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Conformational determinants for the recruitment of ERCC1 by XPA in the nucleotide excision repair (NER) Pathway: structure and dynamics of the XPA binding motif. Biophys J 2014; 104:2503-11. [PMID: 23746523 DOI: 10.1016/j.bpj.2013.04.023] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2012] [Revised: 04/08/2013] [Accepted: 04/10/2013] [Indexed: 11/23/2022] Open
Abstract
XPA is an essential protein in the nucleotide excision repair (NER) pathway, in charge of recruiting the ERCC1-XPF endonuclease complex to the DNA damage site. The only currently available structural insight into the binding of XPA to ERCC1 derives from the solution NMR structure of a complex between the ERCC1 central fragment and a 14-residue peptide, corresponding to the highly conserved binding motif of the XPA N-terminus, XPA₆₇₋₈₀. The extensive all-atom molecular-dynamics simulation study of the XPA₆₇₋₈₀ peptide both bound to the ERCC1 central fragment and free in solution presented here completes the profile of the structural determinants responsible for the ERCC1/XPA₆₇₋₈₀ complex stability. In addition to the wild-type, this study also looks at specific XPA₆₇₋₈₀ mutants in complex with the ERCC1 central domain and thus contributes to defining the conformational determinants for binding, as well as all of the essential structural elements necessary for the rational design of an XPA-based, ERCC1-specific inhibitor.
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102
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Matthaios D, Hountis P, Karakitsos P, Bouros D, Kakolyris S. H2AX a Promising Biomarker for Lung Cancer: A Review. Cancer Invest 2013; 31:582-99. [DOI: 10.3109/07357907.2013.849721] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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103
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Morse JL, Luczak MW, Zhitkovich A. Chromium(VI) causes interstrand DNA cross-linking in vitro but shows no hypersensitivity in cross-link repair-deficient human cells. Chem Res Toxicol 2013; 26:1591-8. [PMID: 24059640 DOI: 10.1021/tx400293s] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Hexavalent chromium is a human carcinogen activated primarily by direct reduction with cellular ascorbate and to a lesser extent, by glutathione. Cr(III), the final product of Cr(VI) reduction, forms six bonds allowing intermolecular cross-linking. In this work, we investigated the ability of Cr(VI) to cause interstrand DNA cross-links (ICLs) whose formation mechanisms and presence in human cells are currently uncertain. We found that in vitro reduction of Cr(VI) with glutathione showed a sublinear production of ICLs, the yield of which was less than 1% of total Cr-DNA adducts at the optimal conditions. Formation of ICLs in fast ascorbate-Cr(VI) reactions occurred during a short reduction interval and displayed a linear dose dependence with the average yield of 1.3% of total adducts. In vitro production of ICLs was strongly suppressed by increasing buffer molarity, indicating inhibitory effects of ligand-Cr(III) binding on the formation of cross-linking species. The presence of ICLs in human cells was assessed from the impact of ICL repair deficiencies on Cr(VI) responses. We found that ascorbate-restored FANCD2-null and isogenic FANCD2-complemented cells showed similar cell cycle inhibition and toxicity by Cr(VI). XPA-null cells are defective in the repair of Cr-DNA monoadducts, but stable knockdowns of ERCC1 or XPF in these cells with extended time for the completion of cross-linking reactions did not produce any sensitization to Cr(VI). Our results together with chemical and steric considerations of Cr(III) reactivity suggest that ICL generation by chromate is probably an in vitro phenomenon occurring at conditions permitting the formation of Cr(III) oligomers.
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Affiliation(s)
- Jessica L Morse
- Department of Pathology and Laboratory Medicine, Brown University , 70 Ship Street, Providence, Rhode Island 02912, United States
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104
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Friboulet L, Postel-Vinay S, Sourisseau T, Adam J, Stoclin A, Ponsonnailles F, Dorvault N, Commo F, Saulnier P, Salome-Desmoulez S, Pottier G, André F, Kroemer G, Soria JC, Olaussen KA. ERCC1 function in nuclear excision and interstrand crosslink repair pathways is mediated exclusively by the ERCC1-202 isoform. Cell Cycle 2013; 12:3298-306. [PMID: 24036546 DOI: 10.4161/cc.26309] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
ERCC1 (excision repair cross-complementation group 1) plays essential roles in the removal of DNA intrastrand crosslinks by nucleotide excision repair, and that of DNA interstrand crosslinks by the Fanconi anemia (FA) pathway and homology-directed repair processes (HDR). The function of ERCC1 thus impacts on the DNA damage response (DDR), particularly in anticancer therapy when DNA damaging agents are employed. ERCC1 expression has been proposed as a predictive biomarker of the response to platinum-based therapy. However, the assessment of ERCC1 expression in clinical samples is complicated by the existence of 4 functionally distinct protein isoforms, which differently impact on DDR. Here, we explored the functional competence of each ERCC1 protein isoform and obtained evidence that the 202 isoform is the sole one endowed with ERCC1 activity in DNA repair pathways. The ERCC1 isoform 202 interacts with RPA, XPA, and XPF, and XPF stability requires expression of the ERCC1 202 isoform (but none of the 3 others). ERCC1-deficient non-small cell lung cancer cells show abnormal mitosis, a phenotype reminiscent of the FA phenotype that can be rescued by isoform 202 only. Finally, we could not observe any dominant-negative interaction between ERCC1 isoforms. These data suggest that the selective assessment of the ERCC1 isoform 202 in clinical samples should accurately reflect the DDR-related activity of the gene and hence constitute a useful biomarker for customizing anticancer therapies.
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Affiliation(s)
- Luc Friboulet
- Gustave Roussy; Villejuif, France; INSERM, U981; IRCIV; Villejuif, France; Département Hospitalo-Universitaire Thorax Innovation (DHU TORINO); Villejuif, France; Université Paris Sud; Kremlin-Bicêtre, France
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105
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Kothandapani A, Sawant A, Dangeti VSMN, Sobol RW, Patrick SM. Epistatic role of base excision repair and mismatch repair pathways in mediating cisplatin cytotoxicity. Nucleic Acids Res 2013; 41:7332-43. [PMID: 23761438 PMCID: PMC3753620 DOI: 10.1093/nar/gkt479] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Base excision repair (BER) and mismatch repair (MMR) pathways play an important role in modulating cis-Diamminedichloroplatinum (II) (cisplatin) cytotoxicity. In this article, we identified a novel mechanistic role of both BER and MMR pathways in mediating cellular responses to cisplatin treatment. Cells defective in BER or MMR display a cisplatin-resistant phenotype. Targeting both BER and MMR pathways resulted in no additional resistance to cisplatin, suggesting that BER and MMR play epistatic roles in mediating cisplatin cytotoxicity. Using a DNA Polymerase β (Polβ) variant deficient in polymerase activity (D256A), we demonstrate that MMR acts downstream of BER and is dependent on the polymerase activity of Polβ in mediating cisplatin cytotoxicity. MSH2 preferentially binds a cisplatin interstrand cross-link (ICL) DNA substrate containing a mismatch compared with a cisplatin ICL substrate without a mismatch, suggesting a novel mutagenic role of Polβ in activating MMR in response to cisplatin. Collectively, these results provide the first mechanistic model for BER and MMR functioning within the same pathway to mediate cisplatin sensitivity via non-productive ICL processing. In this model, MMR participation in non-productive cisplatin ICL processing is downstream of BER processing and dependent on Polβ misincorporation at cisplatin ICL sites, which results in persistent cisplatin ICLs and sensitivity to cisplatin.
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Affiliation(s)
- Anbarasi Kothandapani
- Department of Biochemistry and Cancer Biology, University of Toledo - Health Science Campus, Toledo, OH 43614, USA, Department of Pharmacology & Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA, University of Pittsburgh Cancer Institute, Hillman Cancer Center, Pittsburgh, PA 15213, USA and Department of Human Genetics, University of Pittsburgh Graduate School of Public Health, Pittsburgh, PA 15213, USA
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106
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Jordheim LP, Barakat KH, Heinrich-Balard L, Matera EL, Cros-Perrial E, Bouledrak K, El Sabeh R, Perez-Pineiro R, Wishart DS, Cohen R, Tuszynski J, Dumontet C. Small Molecule Inhibitors of ERCC1-XPF Protein-Protein Interaction Synergize Alkylating Agents in Cancer Cells. Mol Pharmacol 2013; 84:12-24. [DOI: 10.1124/mol.112.082347] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
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107
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Jagdis A, Phan T, Klimowicz AC, Laskin JJ, Lau HY, Petrillo SK, Siever JE, Thomson TA, Magliocco AM, Hao D. Assessment of ERCC1 and XPF Protein Expression Using Quantitative Immunohistochemistry in Nasopharyngeal Carcinoma Patients Undergoing Curative Intent Treatment. Int J Radiat Oncol Biol Phys 2013. [DOI: 10.1016/j.ijrobp.2012.09.032] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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108
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Ayers D, Nasti A. Utilisation of nanoparticle technology in cancer chemoresistance. JOURNAL OF DRUG DELIVERY 2012; 2012:265691. [PMID: 23213536 PMCID: PMC3505656 DOI: 10.1155/2012/265691] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/06/2012] [Revised: 10/11/2012] [Accepted: 10/11/2012] [Indexed: 01/08/2023]
Abstract
The implementation of cytotoxic chemotherapeutic drugs in the fight against cancer has played an invariably essential role for minimizing the extent of tumour progression and/or metastases in the patient and thus allowing for longer event free survival periods following chemotherapy. However, such therapeutics are nonspecific and bring with them dose-dependent cumulative adverse effects which can severely exacerbate patient suffering. In addition, the emergence of innate and/or acquired chemoresistance to the exposed cytotoxic agents undoubtedly serves to thwart effective clinical efficacy of chemotherapy in the cancer patient. The advent of nanotechnology has led to the development of a myriad of nanoparticle-based strategies with the specific goal to overcome such therapeutic hurdles in multiple cancer conditions. This paper aims to provide a brief overview and recollection of all the latest advances in the last few years concerning the application of nanoparticle technology to enhance the safe and effective delivery of chemotherapeutic agents to the tumour site, together with providing possible solutions to circumvent cancer chemoresistance in the clinical setting.
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Affiliation(s)
- Duncan Ayers
- Department of Pathology, Faculty of Medicine & Surgery, University of Malta, Msida MSD 2060, Malta
| | - Alessandro Nasti
- School of Medicine, Kanazawa University Hospital, University of Kanazawa, Kanazawa 920-1192, Japan
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109
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Jones AR, Bell-Horwath TR, Li G, Rollmann SM, Merino EJ. Novel oxidatively activated agents modify DNA and are enhanced by ercc1 silencing. Chem Res Toxicol 2012; 25:2542-52. [PMID: 23051149 DOI: 10.1021/tx300337j] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Agents that chemically modify DNA form a backbone of many cancer treatments. A key problem for DNA-modifying agents is lack of specificity. To address this issue, we designed novel molecular scaffolds, termed An-Hq and An-Hq(2), which are activated by a hallmark of some cancers: elevated concentrations of reactive oxygen species. Elevated reactive oxygen species are linked to oncogenesis and are found to increase in several aggressive cancers. The agents are quinones that, upon oxidation, form highly electrophilic species. In vitro studies identified the mode of addition to DNA. The aniline portion of An-Hq serves to enhance nucleophilic addition to the ethyl phenyl ether instead of forming common Michael additions. Structural characterization showed that the agents add to 2'-deoxyguanosine at the N2,N3-positions. The product formed is a bulky hydroxy-N2,3-benzetheno-2'-deoxyguanosine adduct. In addition, the oxidatively activated agents added to 2'-deoxyadenosine and 2'-deoxycytidine but not thymidine or 2'-deoxyinosine. These findings are confirmed by primer extension analysis of a 392 base pair DNA. The full-length primer extension product was reduced by 69.0 ± 0.6% upon oxidative activation of An-Hq(2) as compared to controls. Little sequence dependence was observed with 76% of guanine, adenine, and cytosine residues showing an increase in extension stops between 2- and 4-fold above controls. Benzetheno-nucleobase addition to double-stranded DNA was confirmed by LC/MS of a self-complementary oligonucletide. Experiments were carried out to confirm in vivo DNA damage. Because of the lesion identified in vitro, we reasoned that nucleotide excision repair should be involved in reversing the effects of these oxidatively activated agents and enhance toxicity in Drosophila melanogaster. Using an RNAi-based approach, Ercc1 was silenced, and survival was monitored after injection of an agent. As expected, bulky cross-linking DNA-modifying agents, cisplatin and chlorambucil, showed statistically significant enhanced toxicity in Drosophila with silenced Ercc1. In addition, 5-fluorouracil, which does not produce bulky lesions, showed no selective toxicity. An-Hq and An-Hq(2) showed statistically significant toxicity in Drosophila with silenced Ercc1. Examination of cytotoxicity shows renal carcinoma cell lines as a target of these agents with a median IC(50) of 1.8 μM. Taken together, these data show that the designed oxidatively activated agents form distinct, bulky DNA modifications that prove difficult for cancer cells possessing an elevated reactive oxygen species phenotype to overcome. The modification produced is relatively unique among anticancer agents.
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Affiliation(s)
- Amy R Jones
- Department of Biological Sciences, University of Cincinnati, Cincinnati, OH 45221-0006, USA
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110
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Drayton RM, Catto JWF. Molecular mechanisms of cisplatin resistance in bladder cancer. Expert Rev Anticancer Ther 2012; 12:271-81. [PMID: 22316374 DOI: 10.1586/era.11.201] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Metastatic disease is the most common mechanism of death in patients with advanced bladder cancer. As for most solid tumors, chemotherapy remains the only realistic option for palliating or curing metastatic disease. However, bladder cancer is characterized by chemoresistance. Only modest response rates are obtained using multiagent regimens including cisplatin. These low response rates and the toxicity of these regimens limit their use to patients at highest risk. Here, we review the molecular mechanisms of cisplatin resistance. These include methods to reduce cisplatin bioavailability within a cell, and defects in the machinery that produces cell death following cisplatin-induced DNA damage. While overcoming these mechanisms is a potential therapeutic approach that can increase response rates, in the short term this knowledge could be used to predict response in individual tumors.
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Affiliation(s)
- Ross M Drayton
- Institute for Cancer Studies and Academic Urology Unit, University of Sheffield, Sheffield, S10 2RX, UK.
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111
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Kothandapani A, Gopalakrishnan K, Kahali B, Reisman D, Patrick SM. Downregulation of SWI/SNF chromatin remodeling factor subunits modulates cisplatin cytotoxicity. Exp Cell Res 2012; 318:1973-86. [PMID: 22721696 PMCID: PMC3408789 DOI: 10.1016/j.yexcr.2012.06.011] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2011] [Revised: 06/05/2012] [Accepted: 06/08/2012] [Indexed: 01/23/2023]
Abstract
Chromatin remodeling complex SWI/SNF plays important roles in many cellular processes including transcription, proliferation, differentiation and DNA repair. In this report, we investigated the role of SWI/SNF catalytic subunits Brg1 and Brm in the cellular response to cisplatin in lung cancer and head/neck cancer cells. Stable knockdown of Brg1 and Brm enhanced cellular sensitivity to cisplatin. Repair kinetics of cisplatin DNA adducts revealed that downregulation of Brg1 and Brm impeded the repair of both intrastrand adducts and interstrand crosslinks (ICLs). Cisplatin ICL-induced DNA double strand break repair was also decreased in Brg1 and Brm depleted cells. Altered checkpoint activation with enhanced apoptosis as well as impaired chromatin relaxation was observed in Brg1 and Brm deficient cells. Downregulation of Brg1 and Brm did not affect the recruitment of DNA damage recognition factor XPC to cisplatin DNA lesions, but affected ERCC1 recruitment, which is involved in the later stages of DNA repair. Based on these results, we propose that SWI/SNF chromatin remodeling complex modulates cisplatin cytotoxicity by facilitating efficient repair of the cisplatin DNA lesions.
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Affiliation(s)
- Anbarasi Kothandapani
- Department of Biochemistry and Cancer Biology, University of Toledo – Health Science Campus, Toledo, OH – 43614, USA
| | - Kathirvel Gopalakrishnan
- Physiological Genomics Laboratory, Department of Physiology and Pharmacology, University of Toledo College of Medicine, Toledo, OH – 43614, USA
| | - Bhaskar Kahali
- Division of Hematology and Oncology, Department of Medicine, University of Florida, Gainesville, FL – 32610, USA
| | - David Reisman
- Division of Hematology and Oncology, Department of Medicine, University of Florida, Gainesville, FL – 32610, USA
| | - Steve M Patrick
- Department of Biochemistry and Cancer Biology, University of Toledo – Health Science Campus, Toledo, OH – 43614, USA
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112
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McNeil EM, Melton DW. DNA repair endonuclease ERCC1-XPF as a novel therapeutic target to overcome chemoresistance in cancer therapy. Nucleic Acids Res 2012; 40:9990-10004. [PMID: 22941649 PMCID: PMC3488251 DOI: 10.1093/nar/gks818] [Citation(s) in RCA: 139] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
The ERCC1–XPF complex is a structure-specific endonuclease essential for the repair of DNA damage by the nucleotide excision repair pathway. It is also involved in other key cellular processes, including DNA interstrand crosslink (ICL) repair and DNA double-strand break (DSB) repair. New evidence has recently emerged, increasing our understanding of its requirement in these additional roles. In this review, we focus on the protein–protein and protein–DNA interactions made by the ERCC1 and XPF proteins and discuss how these coordinate ERCC1–XPF in its various roles. In a number of different cancers, high expression of ERCC1 has been linked to a poor response to platinum-based chemotherapy. We discuss prospects for the development of DNA repair inhibitors that target the activity, stability or protein interactions of the ERCC1–XPF complex as a novel therapeutic strategy to overcome chemoresistance.
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Affiliation(s)
- Ewan M McNeil
- MRC Institute of Genetics and Molecular Medicine, University of Edinburgh, MRC Human Genetics Unit, Western General Hospital, Crewe Road, Edinburgh EH4 2XU, UK
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113
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Saleh EM, El-Awady RA, Anis N, El-Sharkawy N. Induction and repair of DNA double-strand breaks using constant-field gel electrophoresis and apoptosis as predictive markers for sensitivity of cancer cells to cisplatin. Biomed Pharmacother 2012; 66:554-62. [PMID: 22939736 DOI: 10.1016/j.biopha.2012.07.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2012] [Revised: 07/16/2012] [Accepted: 07/16/2012] [Indexed: 11/30/2022] Open
Abstract
This study was designed to evaluate some parameters that may play a role in the prediction of cancer cells sensitivity to cisplatin (CIS). Sensitivity, induction and repair of DNA double-strand breaks (DSB), cell cycle regulation and induction of apoptosis were measured in four cancer cell lines with different sensitivities to CIS. Using a sulphorhodamine-B assay, the cervical carcinoma cells (HeLa) were found to be the most sensitive to CIS followed by breast carcinoma cells (MCF-7) and liver carcinoma cells (HepG2). Colon carcinoma HCT116 cells were the most resistant. As measured by constant-field gel electrophoresis (CFGE), DSB induction, but not residual DSB exhibited a significant correlation with the sensitivity of cells to CIS. Flow cytometric DNA ploidy analysis revealed that 67% of HeLa cells and 10% of MCF-7 cells shift to sub-G1 phase after incubation with CIS. Additionally, CIS induced the arrest of MCF-7 cells in S-phase and the arrest of HepG2 and HCT116 cells in both S phase and G2/M phase. Determination of the Fas-L level and Caspase-9 activity indicated that CIS-induced apoptosis results from the mitochondrial (intrinsic) pathway. These results, if confirmed using clinical samples, indicate that the induction of DNA DSB as measured by CFGE and the induction of apoptosis should be considered, along with other predictive markers, in future clinical trials to develop predictive assays for platinum -based therapy.
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Affiliation(s)
- Ekram M Saleh
- Clinical Biochemistry and Molecular Biology unit, Cancer Biology Department, National Cancer Institute, Cairo University, Cairo, Egypt.
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114
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Li J, Zhang J, Liu Y, Ye G. Increased expression of DNA repair gene XPF enhances resistance to hydroxycamptothecin in bladder cancer. Med Sci Monit 2012; 18:BR156-62. [PMID: 22460090 PMCID: PMC3560829 DOI: 10.12659/msm.882618] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Background Xeroderma pigmentosum group F (XPF) is an important participant in the nucleotide excision repair process. This study aimed to investigate the expression of DNA repair gene xeroderma pigmentosum group F (XPF) in bladder cancer and its clinical significance. Material/Methods Total RNA and protein were extracted from 45 untreated bladder cancer tissues and 21 hydroxycamptothecin (HCPT)-treated bladder cancer specimens. Real-time PCR and Western blot assay were used to detect the mRNA and protein levels of XPF, respectively. siRNA targeting XPF was used to knock down the XPF expression in T24 cells and 5637 cells, and the sensitivity of XPF-depleted cells to HCPT was measured. Results The XPF expressions in the HCPT-treated cancer tissues was significantly higher than those in the untreated cancer tissues at both mRNA and protein levels. Importantly, the enhanced XPF expression decreased the sensitivity of T24 cells and 5637 cells to HCPT. Furthermore, the HCPT treatment significantly increased the apoptosis of T24 cells and 5637 cells. Alternatively, after the XPF gene silencing, the chemotherapeutic resistance of bladder cancer cells was significantly decreased. Conclusions Our results show the increased expression of XPF is involved in the chemotherapeutic resistance of bladder cancer, and decreasing XPF expression may become a promising therapeutic strategy for bladder cancer.
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Affiliation(s)
- Jie Li
- Department of Urology, 2nd Affiliated Hospital, 3rd Military Medical University, Chongqing, China
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115
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Facista A, Nguyen H, Lewis C, Prasad AR, Ramsey L, Zaitlin B, Nfonsam V, Krouse RS, Bernstein H, Payne CM, Stern S, Oatman N, Banerjee B, Bernstein C. Deficient expression of DNA repair enzymes in early progression to sporadic colon cancer. Genome Integr 2012; 3:3. [PMID: 22494821 PMCID: PMC3351028 DOI: 10.1186/2041-9414-3-3] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2011] [Accepted: 04/11/2012] [Indexed: 12/11/2022] Open
Abstract
Background Cancers often arise within an area of cells (e.g. an epithelial patch) that is predisposed to the development of cancer, i.e. a "field of cancerization" or "field defect." Sporadic colon cancer is characterized by an elevated mutation rate and genomic instability. If a field defect were deficient in DNA repair, DNA damages would tend to escape repair and give rise to carcinogenic mutations. Purpose To determine whether reduced expression of DNA repair proteins Pms2, Ercc1 and Xpf (pairing partner of Ercc1) are early steps in progression to colon cancer. Results Tissue biopsies were taken during colonoscopies of 77 patients at 4 different risk levels for colon cancer, including 19 patients who had never had colonic neoplasia (who served as controls). In addition, 158 tissue samples were taken from tissues near or within colon cancers removed by resection and 16 tissue samples were taken near tubulovillous adenomas (TVAs) removed by resection. 568 triplicate tissue sections (a total of 1,704 tissue sections) from these tissue samples were evaluated by immunohistochemistry for 4 DNA repair proteins. Substantially reduced protein expression of Pms2, Ercc1 and Xpf occurred in field defects of up to 10 cm longitudinally distant from colon cancers or TVAs and within colon cancers. Expression of another DNA repair protein, Ku86, was infrequently reduced in these areas. When Pms2, Ercc1 or Xpf were reduced in protein expression, then either one or both of the other two proteins most often had reduced protein expression as well. The mean inner colon circumferences, from 32 resections, of the ascending, transverse and descending/sigmoid areas were measured as 6.6 cm, 5.8 cm and 6.3 cm, respectively. When combined with other measurements in the literature, this indicates the approximate mean number of colonic crypts in humans is 10 million. Conclusions The substantial deficiencies in protein expression of DNA repair proteins Pms2, Ercc1 and Xpf in about 1 million crypts near cancers and TVAs suggests that the tumors arose in field defects that were deficient in DNA repair and that deficiencies in Pms2, Ercc1 and Xpf are early steps, often occurring together, in progression to colon cancer.
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Affiliation(s)
- Alexander Facista
- Southern Arizona Veterans Affairs Heath Care System, Mail Stop 0-151, 3601 S, 6th Ave,, Tucson, Arizona 85723, USA.
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116
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Tang C, Yang H, Zhou X. [Advances of DNA damage repair and Cisplatin resistance mechanisms in lung cancer]. ZHONGGUO FEI AI ZA ZHI = CHINESE JOURNAL OF LUNG CANCER 2011; 14:960-4. [PMID: 22152698 PMCID: PMC6000195 DOI: 10.3779/j.issn.1009-3419.2011.12.11] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Lung cancer is the most common cause of death from cancer worldwide per year. Platinum-based combination chemotherapy is a main treatment of lung cancer. Cisplatin is adopted widely and used effectively in the first-line chemotherapy. Unfortunately, development of cisplatin resistance is a major obstacle to the success of lung caner. Cisplatin is a cell-cycle-non-specific cytotoxic drugs and its main target is DNA. Thus, defective DNA damage repair is one of the main mechanisms of cisplatin resistance. In this review, we will focus on the defective DNA damage repair in cisplatin resistance of lung cancer including nucleotide excision repair, DNA mismatch repair, DNA double-strand break repair and translesion synthesis.
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Affiliation(s)
- Chunlan Tang
- Department of Respiratory Medicine, Southwest Hospital, Third Military Medical University, Chongqing 400038, China
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117
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Wang LE, Yin M, Dong Q, Stewart DJ, Merriman KW, Amos CI, Spitz MR, Wei Q. DNA repair capacity in peripheral lymphocytes predicts survival of patients with non-small-cell lung cancer treated with first-line platinum-based chemotherapy. J Clin Oncol 2011; 29:4121-8. [PMID: 21947825 DOI: 10.1200/jco.2010.34.3616] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
PURPOSE Platinum-based regimens are the standard chemotherapy for patients with advanced non-small-cell lung cancer (NSCLC). DNA repair capacity (DRC) in tumor cells plays an important role in resistance to platinum-based drugs. We have previously reported that efficient DRC, as assessed by an in vitro lymphocyte-based assay, was a determinant of poor survival in patients with NSCLC in a relatively small data set. In this larger independent study of 591 patients with NSCLC, we further evaluated whether DRC in peripheral lymphocytes predicts survival of patients with NSCLC who receive platinum-based chemotherapy. PATIENTS AND METHODS All patients were recruited at The University of Texas MD Anderson Cancer Center and donated blood samples before the start of any chemotherapy. We measured DRC in cultured T lymphocytes by using the host-cell reactivation assay, and we assessed associations between DRC in peripheral lymphocytes and survival of patients with NSCLC who were treated with first-line platinum-based chemotherapy. RESULTS We found an inverse association between DRC in peripheral lymphocytes and patient survival. Compared with patients in the low tertile of DRC, patients with NSCLC in the high tertile of DRC had significantly worse overall and 3-year survival (adjusted hazard ratio [HR], 1.33; 95% CI, 1.04 to 1.71; P = .023; and HR, 1.35; 95% CI, 1.04 to 1.76; P = .025, respectively). This trend was more pronounced in patients with early-stage tumors, adenocarcinoma, or squamous cell carcinoma. CONCLUSION We confirmed that DRC in peripheral lymphocytes is an independent predictor of survival for patients with NSCLC treated with platinum-based chemotherapy.
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Affiliation(s)
- Li-E Wang
- The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX 77030, USA
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118
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Jalal S, Earley JN, Turchi JJ. DNA repair: from genome maintenance to biomarker and therapeutic target. Clin Cancer Res 2011; 17:6973-84. [PMID: 21908578 DOI: 10.1158/1078-0432.ccr-11-0761] [Citation(s) in RCA: 85] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
A critical link exists between an individual's ability to repair cellular DNA damage and cancer development, progression, and response to therapy. Knowledge gained about the proteins involved and types of damage repaired by the individual DNA repair pathways has led to the development of a variety of assays aimed at determining an individual's DNA repair capacity. These assays and their use in the analysis of clinical samples have yielded useful though somewhat conflicting data. In this review article, we discuss the major DNA repair pathways, the proteins and genes required for each, assays used to analyze activity, and the relevant clinical studies to date. With the recent results from clinical trials targeting specific DNA repair proteins for the treatment of cancer, accurate, reproducible, and relevant analysis of DNA repair takes on an even greater significance. We highlight the strengths and limitations of these DNA repair studies and assays, with respect to the clinical assessment of DNA repair capacity to determine cancer development and response to therapy.
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Affiliation(s)
- Shadia Jalal
- Division of Hematology and Oncology, Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana 46202, USA
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119
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Rageul J, Frëmin C, Ezan F, Baffet G, Langouët S. The knock-down of ERCC1 but not of XPF causes multinucleation. DNA Repair (Amst) 2011; 10:978-90. [DOI: 10.1016/j.dnarep.2011.07.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2011] [Revised: 07/18/2011] [Accepted: 07/19/2011] [Indexed: 11/26/2022]
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120
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Song L, Ritchie AM, McNeil EM, Li W, Melton DW. Identification of DNA repair gene Ercc1 as a novel target in melanoma. Pigment Cell Melanoma Res 2011; 24:966-71. [DOI: 10.1111/j.1755-148x.2011.00882.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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121
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Soares DG, Machado MS, Rocca CJ, Poindessous V, Ouaret D, Sarasin A, Galmarini CM, Henriques JA, Escargueil AE, Larsen AK. Trabectedin and Its C Subunit Modified Analogue PM01183 Attenuate Nucleotide Excision Repair and Show Activity toward Platinum-Resistant Cells. Mol Cancer Ther 2011; 10:1481-9. [DOI: 10.1158/1535-7163.mct-11-0252] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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122
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Yin JY, Shen J, Dong ZZ, Huang Q, Zhong MZ, Feng DY, Zhou HH, Zhang JT, Liu ZQ. Effect of eIF3a on response of lung cancer patients to platinum-based chemotherapy by regulating DNA repair. Clin Cancer Res 2011; 17:4600-9. [PMID: 21610145 DOI: 10.1158/1078-0432.ccr-10-2591] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE The purpose of this study is to test the hypothesis that eIF3a may regulate the expression of DNA repair proteins which, in turn, affects response of lung cancer patients to treatments by DNA-damaging anticancer drugs. EXPERIMENTAL DESIGN Immunohistochemistry was used to determine the expression of eIF3a in 211 human lung cancer tissues followed by association analysis of eIF3a expression with patient's response to platinum-based chemotherapy. Ectopic overexpression and RNA interference knockdown of eIF3a were carried out in NIH3T3 and H1299 cell lines, respectively, to determine the effect of altered eIF3a expression on cellular response to cisplatin, doxorubicine, etoposide (VP-16), vincristine, and vinblastine by using MTT assay. The DNA repair capacity of these cells was evaluated by using host-cell reactivation assay. Real-time reverse transcriptase PCR and Western Blot analyses were carried out to determine the effect of eIF3a on the DNA repair genes by using cells with altered eIF3a expression. RESULTS eIF3a expression associates with response of lung cancer patients to platinum-based chemotherapy. eIF3a knockdown or overexpression, respectively, increased and decreased the cellular resistance to cisplatin and anthrocycline anticancer drugs, DNA repair activity, and expression of DNA repair proteins. CONCLUSIONS eIF3a plays an important role in regulating the expression of DNA repair proteins which, in turn, contributes to cellular response to DNA-damaging anticancer drugs and patients' response to platinum-based chemotherapy.
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Affiliation(s)
- Ji-Ye Yin
- Institute of Clinical Pharmacology, Hunan Key Laboratory of Pharmacogenetics, Xiang-Ya Hospital, Central South University, Changsha, Hunan, PR China
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123
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Malavasi N, Ferrara L, Fiorani C, Saviola A, Longo G. Diagnostic delay in oncology: a case report of metastatic seminoma. Case Rep Oncol 2011; 4:216-21. [PMID: 21516272 PMCID: PMC3080788 DOI: 10.1159/000327697] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Germ cell tumours are the most common malignancy among young men; cryptorchidism is a possible risk factor for the development of testicular cancer. Psycho-oncology studies indicate that diagnostic delay can often be explained by different social conditions and that symptoms worsened under lack of appropriate treatment can lead to an urgent admission to the hospital. Nevertheless, germ cell tumours are considered curable malignancies even in advanced stages since the introduction of a chemotherapy regimen based on bleomycin, etoposide and cisplatin. Cell lines derived from germ cell tumours are sensitive to cisplatin-based treatment more than other solid cancers, which is reflected in the good clinical response. We report an unusual manifestation of malignancy in an adult man presenting with a metastatic seminoma of the left testicle. The large ulcerate and necrotic mass suggested a secondary infection from a tumour site. The patient reported surgical orchiopexy for left cryptorchidism in his childhood. Despite worsening of physical features, he had not sought help at the hospital for social reasons. The patient achieved complete clinical remission after receiving standard chemotherapy, and a good objective response of the primitive mass was clearly visible. Complete response was persistent at the 30-month clinical follow-up. The chemotherapy administration was later complicated by acute haemorrage in the site of the primitive tumour that needed urgent surgical management; in addition to this, the artificial graft material was rejected and the arterial prosthesis had to be removed. This case report can be considered for epidemiologic contribute, for clinical relevance despite diagnostic delay and for psycho-oncology studies.
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Affiliation(s)
- Norma Malavasi
- Department of Oncology and Haematology, University of Modena and Reggio Emilia, Modena, Italy
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124
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Graf N, Ang WH, Zhu G, Myint M, Lippard SJ. Role of endonucleases XPF and XPG in nucleotide excision repair of platinated DNA and cisplatin/oxaliplatin cytotoxicity. Chembiochem 2011; 12:1115-23. [PMID: 21452186 DOI: 10.1002/cbic.201000724] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2010] [Indexed: 12/12/2022]
Abstract
Resistance of tumor cells to platinum anticancer agents poses a major problem in cancer chemotherapy. One of the mechanisms associated with platinum-based drug resistance is the enhanced capacity of the cell to carry out nucleotide excision repair (NER) on platinum-damaged DNA. Endonucleases XPF and XPG are critical components of NER, responsible for excising the damaged DNA strand to remove the DNA lesion. Here, we investigated possible consequences of down-regulation of XPF and XPG gene expression in osteosarcoma cancer cells (U2OS) and the impact on cellular transcription and DNA repair. We further evaluated the sensitivity of such cells toward the platinum anticancer drugs cisplatin and oxaliplatin.
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Affiliation(s)
- Nora Graf
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, 02139, USA
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125
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Wang QE, Milum K, Han C, Huang YW, Wani G, Thomale J, Wani AA. Differential contributory roles of nucleotide excision and homologous recombination repair for enhancing cisplatin sensitivity in human ovarian cancer cells. Mol Cancer 2011; 10:24. [PMID: 21385444 PMCID: PMC3064653 DOI: 10.1186/1476-4598-10-24] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2011] [Accepted: 03/08/2011] [Indexed: 11/10/2022] Open
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 of the sensitivity to cisplatin, and suggest that manipulation of the HRR but not the NER factor expression provides an effective strategy for sensitizing cisplatin-resistant tumors to platinating agents.
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Affiliation(s)
- Qi-En Wang
- Department of Radiology, The Ohio State University, Columbus, OH 43210, USA.
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126
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Kothandapani A, Dangeti VSMN, Brown AR, Banze LA, Wang XH, Sobol RW, Patrick SM. Novel role of base excision repair in mediating cisplatin cytotoxicity. J Biol Chem 2011; 286:14564-74. [PMID: 21357694 DOI: 10.1074/jbc.m111.225375] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Using isogenic mouse embryonic fibroblasts and human cancer cell lines, we show that cells defective in base excision repair (BER) display a cisplatin-specific resistant phenotype. This was accompanied by enhanced repair of cisplatin interstrand cross-links (ICLs) and ICL-induced DNA double strand breaks, but not intrastrand adducts. Cisplatin induces abasic sites with a reduced accumulation in uracil DNA glycosylase (UNG) null cells. We show that cytosines that flank the cisplatin ICLs undergo preferential oxidative deamination in vitro, and AP endonuclease 1 (APE1) can cleave the resulting ICL DNA substrate following removal of the flanking uracil. We also show that DNA polymerase β has low fidelity at the cisplatin ICL site after APE1 incision. Down-regulating ERCC1-XPF in BER-deficient cells restored cisplatin sensitivity. Based on our results, we propose a novel model in which BER plays a positive role in maintaining cisplatin cytotoxicity by competing with the productive cisplatin ICL DNA repair pathways.
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Affiliation(s)
- Anbarasi Kothandapani
- Department of Biochemistry and Cancer Biology, University of Toledo, Health Science Campus, Toledo, Ohio 43614, USA
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127
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Köberle B, Tomicic MT, Usanova S, Kaina B. Cisplatin resistance: Preclinical findings and clinical implications. Biochim Biophys Acta Rev Cancer 2010; 1806:172-82. [PMID: 20647037 DOI: 10.1016/j.bbcan.2010.07.004] [Citation(s) in RCA: 183] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2010] [Revised: 07/07/2010] [Accepted: 07/12/2010] [Indexed: 02/03/2023]
Affiliation(s)
- Beate Köberle
- Institute of Toxicology, University Medical Center Mainz, Germany.
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128
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Bagnyukova TV, Serebriiskii IG, Zhou Y, Hopper-Borge EA, Golemis EA, Astsaturov I. Chemotherapy and signaling: How can targeted therapies supercharge cytotoxic agents? Cancer Biol Ther 2010; 10:839-53. [PMID: 20935499 PMCID: PMC3012138 DOI: 10.4161/cbt.10.9.13738] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2010] [Accepted: 08/02/2010] [Indexed: 12/19/2022] Open
Abstract
In recent years, oncologists have begun to conclude that chemotherapy has reached a plateau of efficacy as a primary treatment modality, even if toxicity can be effectively controlled. Emerging specific inhibitors of signaling and metabolic pathways (i.e., targeted agents) contrast with traditional chemotherapy drugs in that the latter primarily interfere with the DNA biosynthesis and the cell replication machinery. In an attempt to improve on the efficacy, combination of targeted drugs with conventional chemotherapeutics has become a routine way of testing multiple new agents in early phase clinical trials. This review discusses the recent advances including integrative systematic biology and RNAi approaches to counteract the chemotherapy resistance and to buttress the selectivity, efficacy and personalization of anti-cancer drug therapy.
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129
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Basu A, Krishnamurthy S. Cellular responses to Cisplatin-induced DNA damage. J Nucleic Acids 2010; 2010:201367. [PMID: 20811617 PMCID: PMC2929606 DOI: 10.4061/2010/201367] [Citation(s) in RCA: 315] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2010] [Accepted: 06/28/2010] [Indexed: 12/29/2022] Open
Abstract
Cisplatin is one of the most effective anticancer agents widely used in the treatment of solid tumors. It is generally considered as a cytotoxic drug which kills cancer cells by damaging DNA and inhibiting DNA synthesis. How cells respond to cisplatin-induced DNA damage plays a critical role in deciding cisplatin sensitivity. Cisplatin-induced DNA damage activates various signaling pathways to prevent or promote cell death. This paper summarizes our current understandings regarding the mechanisms by which cisplatin induces cell death and the bases of cisplatin resistance. We have discussed various steps, including the entry of cisplatin inside cells, DNA repair, drug detoxification, DNA damage response, and regulation of cisplatin-induced apoptosis by protein kinases. An understanding of how various signaling pathways regulate cisplatin-induced cell death should aid in the development of more effective therapeutic strategies for the treatment of cancer.
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Affiliation(s)
- Alakananda Basu
- Department of Molecular Biology & Immunology, University of North Texas Health Science Center and Institute for Cancer Research, 3500 Camp Bowie Boulevard, Fort Worth, TX 76107, USA
| | - Soumya Krishnamurthy
- Department of Molecular Biology & Immunology, University of North Texas Health Science Center and Institute for Cancer Research, 3500 Camp Bowie Boulevard, Fort Worth, TX 76107, USA
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