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Thomas AF, Kelly GL, Strasser A. Of the many cellular responses activated by TP53, which ones are critical for tumour suppression? Cell Death Differ 2022; 29:961-971. [PMID: 35396345 PMCID: PMC9090748 DOI: 10.1038/s41418-022-00996-z] [Citation(s) in RCA: 42] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Revised: 03/24/2022] [Accepted: 03/28/2022] [Indexed: 12/12/2022] Open
Abstract
The tumour suppressor TP53 is a master regulator of several cellular processes that collectively suppress tumorigenesis. The TP53 gene is mutated in ~50% of human cancers and these defects usually confer poor responses to therapy. The TP53 protein functions as a homo-tetrameric transcription factor, directly regulating the expression of ~500 target genes, some of them involved in cell death, cell cycling, cell senescence, DNA repair and metabolism. Originally, it was thought that the induction of apoptotic cell death was the principal mechanism by which TP53 prevents the development of tumours. However, gene targeted mice lacking the critical effectors of TP53-induced apoptosis (PUMA and NOXA) do not spontaneously develop tumours. Indeed, even mice lacking the critical mediators for TP53-induced apoptosis, G1/S cell cycle arrest and cell senescence, namely PUMA, NOXA and p21, do not spontaneously develop tumours. This suggests that TP53 must activate additional cellular responses to mediate tumour suppression. In this review, we will discuss the processes by which TP53 regulates cell death, cell cycling/cell senescence, DNA damage repair and metabolic adaptation, and place this in context of current understanding of TP53-mediated tumour suppression.
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Affiliation(s)
- Annabella F Thomas
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia.,The Department of Medical Biology, The University of Melbourne, Melbourne, VIC, Australia
| | - Gemma L Kelly
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia.,The Department of Medical Biology, The University of Melbourne, Melbourne, VIC, Australia
| | - Andreas Strasser
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia. .,The Department of Medical Biology, The University of Melbourne, Melbourne, VIC, Australia.
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Zebian A, El-Dor M, Shaito A, Mazurier F, Rezvani HR, Zibara K. XPC multifaceted roles beyond DNA damage repair: p53-dependent and p53-independent functions of XPC in cell fate decisions. MUTATION RESEARCH. REVIEWS IN MUTATION RESEARCH 2022; 789:108400. [PMID: 35690409 DOI: 10.1016/j.mrrev.2021.108400] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2021] [Revised: 11/19/2021] [Accepted: 11/19/2021] [Indexed: 06/15/2023]
Abstract
Xeroderma pigmentosum group C protein (XPC) acts as a DNA damage recognition factor for bulky adducts and as an initiator of global genome nucleotide excision repair (GG-NER). Novel insights have shown that the role of XPC is not limited to NER, but is also implicated in DNA damage response (DDR), as well as in cell fate decisions upon stress. Moreover, XPC has a proteolytic role through its interaction with p53 and casp-2S. XPC is also able to determine cellular outcomes through its interaction with downstream proteins, such as p21, ARF, and p16. XPC interactions with effector proteins may drive cells to various fates such as apoptosis, senescence, or tumorigenesis. In this review, we explore XPC's involvement in different molecular pathways in the cell and suggest that XPC can be considered not only as a genomic caretaker and gatekeeper but also as a tumor suppressor and cellular-fate decision maker. These findings envisage that resistance to cell death, induced by DNA-damaging therapeutics, in highly prevalent P53-deficent tumors might be overcome through new therapeutic approaches that aim to activate XPC in these tumors. Moreover, this review encourages care providers to consider XPC status in cancer patients before chemotherapy in order to improve the chances of successful treatment and enhance patients' survival.
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Affiliation(s)
- Abir Zebian
- University of Bordeaux, INSERM U1035, BMGIC, Bordeaux, France; PRASE, Lebanese University, Beirut, Lebanon
| | | | - Abdullah Shaito
- Biomedical Research Center, Qatar University, P.O. Box 2713, Doha, Qatar
| | | | | | - Kazem Zibara
- PRASE, Lebanese University, Beirut, Lebanon; Biology Department, Faculty of Sciences - I, Lebanese University, Beirut, Lebanon.
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3
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Xeroderma Pigmentosum C: A Valuable Tool to Decipher the Signaling Pathways in Skin Cancers. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2021; 2021:6689403. [PMID: 34630850 PMCID: PMC8495593 DOI: 10.1155/2021/6689403] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/22/2020] [Revised: 03/24/2021] [Accepted: 04/19/2021] [Indexed: 12/13/2022]
Abstract
Xeroderma pigmentosum (XP) is a rare autosomal genodermatosis that manifests clinically with pronounced sensitivity to ultraviolet (UV) radiation and the high probability of the occurrence of different skin cancer types in XP patients. XP is mainly caused by mutations in XP-genes that are involved in the nucleotide excision repair (NER) pathway that functions in the removal of bulky DNA adducts. Besides, the aggregation of DNA lesions is a life-threatening event that might be a key for developing various mutations facilitating cancer appearance. One of the key players of NER is XPC that senses helical distortions found in damaged DNA. The majority of XPC gene mutations are nonsense, and some are missense leading either to the loss of XPC protein or to the expression of a truncated nonfunctional version. Given that no cure is yet available, XPC patients should be completely protected and isolated from all types of UV radiations (UVR). Although it is still poorly understood, the characterization of the proteomic signature of an XPC mutant is essential to identify mediators that could be targeted to prevent cancer development in XPC patients. Unraveling this proteomic signature is fundamental to decipher the signaling pathways affected by the loss of XPC expression following exposure to UVB radiation. In this review, we will focus on the signaling pathways disrupted in skin cancer, pathways modulating NER's function, including XPC, to disclose signaling pathways associated with XPC loss and skin cancer occurrence.
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Chen JC, Ko JC, Taso YC, Cheng HH, Chen TY, Yen TC, Lin YW. Downregulation of Xeroderma Pigmentosum Complementation Group C Expression by 17-Allylamino-17-Demethoxygeldanamycin Enhances Bevacizumab-Induced Cytotoxicity in Human Lung Cancer Cells. Pharmacology 2020; 106:154-168. [PMID: 33202406 DOI: 10.1159/000509052] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Accepted: 05/29/2020] [Indexed: 11/19/2022]
Abstract
INTRODUCTION Xeroderma pigmentosum complementation group C (XPC) protein is an important DNA damage recognition factor involved in nucleotide excision repair and regulation of non-small-cell lung cancer (NSCLC) cell proliferation and viability. 17-Allylamino-17-demethoxygeldanamycin (17-AAG) blocks ATP binding to heat shock protein 90 (Hsp90), resulting in destabilization of Hsp90-client protein complexes. Vascular endothelial growth factor (VEGF) is a potent angiogenic growth factor expressed by many types of tumors. Bevacizumab (Avastin) is a humanized monoclonal antibody against human VEGF used as an antiangiogenesis agent in the therapy of many cancers, proving successful in increasing objective tumor response rate and prolonging overall survival in NSCLC patients. METHODS After the bevacizumab and/or 17-AAG treatment, the expressions of XPC mRNA were determined by quantitative real-time PCR analysis. Protein levels of XPC and phospho-AKT were determined by Western blot analysis. We used specific XPC small interfering RNA and PI3K inhibitor (LY294002) to examine the role of the AKT-XPC signal in regulating the chemosensitivity of bevacizumab and 17-AAG. Cell viability was assessed by the MTS assay and trypan blue exclusion assay. RESULTS In this study, bevacizumab decreased XPC expression in human lung squamous cell carcinoma H520 and H1703 cells via AKT inactivation. Enhancement of AKT activity by transfection with constitutively active AKT vectors increased XPC expression and cell survival after treatment with bevacizumab. In addition, 17-AAG synergistically enhanced bevacizumab-induced cytotoxicity and cell growth inhibition in H520 and H1703 cells, associated with downregulation of XPC expression and inactivation of AKT. DISCUSSION/CONCLUSION Together, these results may provide a rationale to combine bevacizumab with Hsp90 inhibitors in future to enhance therapeutic effects for lung cancer.
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Affiliation(s)
- Jyh-Cheng Chen
- Department of Food Science, National Chiayi University, Chiayi, Taiwan
| | - Jen-Chung Ko
- Department of Internal Medicine, National Taiwan University Hospital, Hsin-Chu Branch, Hsin-Chu, Taiwan
| | - Yong-Cing Taso
- Department of Biochemical Science and Technology, National Chiayi University, Chiayi, Taiwan
| | - Hsiang-Hung Cheng
- Department of Biochemical Science and Technology, National Chiayi University, Chiayi, Taiwan
| | - Tzu-Ying Chen
- Department of Biochemical Science and Technology, National Chiayi University, Chiayi, Taiwan
| | - Ting-Chuan Yen
- Department of Biochemical Science and Technology, National Chiayi University, Chiayi, Taiwan
| | - Yun-Wei Lin
- Department of Biochemical Science and Technology, National Chiayi University, Chiayi, Taiwan,
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Zebian A, Shaito A, Mazurier F, Rezvani HR, Zibara K. XPC beyond nucleotide excision repair and skin cancers. MUTATION RESEARCH-REVIEWS IN MUTATION RESEARCH 2019; 782:108286. [DOI: 10.1016/j.mrrev.2019.108286] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Revised: 05/23/2019] [Accepted: 07/05/2019] [Indexed: 12/17/2022]
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Chen JC, Wu CH, Peng YS, Zheng HY, Lin YC, Ma PF, Yen TC, Chen TY, Lin YW. Astaxanthin enhances erlotinib-induced cytotoxicity by p38 MAPK mediated xeroderma pigmentosum complementation group C (XPC) down-regulation in human lung cancer cells. Toxicol Res (Camb) 2018; 7:1247-1256. [PMID: 30555679 DOI: 10.1039/c7tx00292k] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Accepted: 09/07/2018] [Indexed: 12/11/2022] Open
Abstract
Astaxanthin has been demonstrated to exhibit a wide range of beneficial effects that include anti-cancer and anti-inflammatory properties. Xeroderma pigmentosum complementation group C (XPC) protein is an important DNA damage recognition factor in nucleotide excision repair and is involved in regulating non-small cell lung cancer (NSCLC) cell proliferation and viability. Erlotinib (TarcevaR) is a selective epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor that has demonstrated clinical activity in NSCLC cells. However, whether astaxanthin and erlotinib could induce synergistic cytotoxicity in NSCLC cells through modulating XPC expression is unknown. In this study, we found that p38 MAPK activation by astaxanthin decreased XPC expression in two human lung adenocarcinoma A549 and H1975 cells. Inactivation of p38 MAPK by pharmacological inhibitor SB203580 or the specific small interfering RNA (siRNA) rescued the astaxanthin-reduced XPC mRNA and protein levels. Enforced expression of XPC cDNA or inhibiting the p38 MAPK activity reduced the cytotoxicity and cell growth inhibition of astaxanthin. In contrast, knockdown of XPC using siRNA enhanced the cytotoxic effects of astaxanthin. Moreover, astaxanthin synergistically enhanced cytotoxicity and cell growth inhibition of erlotinib in NSCLC cells, which were associated with the down-regulation of XPC expression and activation of p38 MAPK. Our findings suggested that the astaxanthin induced p38 MAPK mediated XPC down-regulation enhanced the erlotinib-induced cytotoxicity in A549 and H1975 cells.
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Affiliation(s)
- Jyh-Cheng Chen
- Department of Food Science , National Chiayi University , Chiayi , Taiwan
| | - Chia-Hung Wu
- Department of Biochemical Science and Technology , National Chiayi University , Chiayi , Taiwan . ; ; Tel: +886-5-271-7770
| | - Yi-Shuan Peng
- Department of Biochemical Science and Technology , National Chiayi University , Chiayi , Taiwan . ; ; Tel: +886-5-271-7770
| | - Hao-Yu Zheng
- Department of Biochemical Science and Technology , National Chiayi University , Chiayi , Taiwan . ; ; Tel: +886-5-271-7770
| | - Yuan-Cheng Lin
- Department of Biochemical Science and Technology , National Chiayi University , Chiayi , Taiwan . ; ; Tel: +886-5-271-7770
| | - Peng-Fang Ma
- Department of Biochemical Science and Technology , National Chiayi University , Chiayi , Taiwan . ; ; Tel: +886-5-271-7770
| | - Ting-Chuan Yen
- Department of Biochemical Science and Technology , National Chiayi University , Chiayi , Taiwan . ; ; Tel: +886-5-271-7770
| | - Tzu-Ying Chen
- Department of Biochemical Science and Technology , National Chiayi University , Chiayi , Taiwan . ; ; Tel: +886-5-271-7770
| | - Yun-Wei Lin
- Department of Biochemical Science and Technology , National Chiayi University , Chiayi , Taiwan . ; ; Tel: +886-5-271-7770
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Cui T, Srivastava AK, Han C, Yang L, Zhao R, Zou N, Qu M, Duan W, Zhang X, Wang QE. XPC inhibits NSCLC cell proliferation and migration by enhancing E-Cadherin expression. Oncotarget 2016; 6:10060-72. [PMID: 25871391 PMCID: PMC4496340 DOI: 10.18632/oncotarget.3542] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2014] [Accepted: 02/13/2015] [Indexed: 02/07/2023] Open
Abstract
Xeroderma pigmentosum complementation group C (XPC) protein is an important DNA damage recognition factor in nucleotide excision repair. Deletion of XPC is associated with early stages of human lung carcinogenesis, and reduced XPC mRNA levels predict poor patient outcome for non-small cell lung cancer (NSCLC). However, the mechanisms linking loss of XPC expression and poor prognosis in lung cancer are still unclear. Here, we report evidence that XPC silencing drives proliferation and migration of NSCLC cells by down-regulating E-Cadherin. XPC knockdown enhanced proliferation and migration while decreasing E-Cadherin expression in NSCLC cells with an epithelial phenotype. Restoration of E-Cadherin in these cells suppressed XPC knockdown-induced cell growth both in vitro and in vivo. Mechanistic studies showed that the loss of XPC repressed E-Cadherin expression by activating the ERK pathway and upregulating Snail expression. Our findings indicate that XPC silencing-induced reduction of E-Cadherin expression contributes, at least in part, to the poor outcome of NSCLC patients with low XPC expression.
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Affiliation(s)
- Tiantian Cui
- Department of Radiology, The Ohio State University Wexner Medical Center, Columbus, OH, USA
| | - Amit Kumar Srivastava
- Department of Radiology, The Ohio State University Wexner Medical Center, Columbus, OH, USA
| | - Chunhua Han
- Department of Radiology, The Ohio State University Wexner Medical Center, Columbus, OH, USA
| | - Linlin Yang
- Department of Radiation Oncology, The Ohio State University Wexner Medical Center, Columbus, OH, USA
| | - Ran Zhao
- Department of Radiology, The Ohio State University Wexner Medical Center, Columbus, OH, USA
| | - Ning Zou
- Department of Radiology, The Ohio State University Wexner Medical Center, Columbus, OH, USA
| | - Meihua Qu
- Department of Radiology, The Ohio State University Wexner Medical Center, Columbus, OH, USA
| | - Wenrui Duan
- Department of Internal Medicine, The Ohio State University Wexner Medical Center, Columbus, OH, USA
| | - Xiaoli Zhang
- Center for Biostatistics, The Ohio State University Wexner Medical Center, Columbus, OH, USA
| | - Qi-En Wang
- Department of Radiology, The Ohio State University Wexner Medical Center, Columbus, OH, USA
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Zhang X, He N, Gu D, Wickliffe J, Salazar J, Boldogh I, Xie J. Genetic Evidence for XPC-KRAS Interactions During Lung Cancer Development. J Genet Genomics 2015; 42:589-596. [PMID: 26554912 DOI: 10.1016/j.jgg.2015.09.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2015] [Revised: 09/16/2015] [Accepted: 09/17/2015] [Indexed: 01/17/2023]
Abstract
Lung cancer causes more deaths than breast, colorectal and prostate cancers combined. Despite major advances in targeted therapy in a subset of lung adenocarcinomas, the overall 5-year survival rate for lung cancer worldwide has not significantly changed for the last few decades. DNA repair deficiency is known to contribute to lung cancer development. In fact, human polymorphisms in DNA repair genes such as xeroderma pigmentosum group C (XPC) are highly associated with lung cancer incidence. However, the direct genetic evidence for the role of XPC for lung cancer development is still lacking. Mutations of the Kirsten rat sarcoma viral oncogene homolog (Kras) or its downstream effector genes occur in almost all lung cancer cells, and there are a number of mouse models for lung cancer with these mutations. Using activated Kras, Kras(LA1), as a driver for lung cancer development in mice, we showed for the first time that mice with Kras(LA1) and Xpc knockout had worst outcomes in lung cancer development, and this phenotype was associated with accumulated DNA damage. Using cultured cells, we demonstrated that induced expression of oncogenic KRAS(G12V) led to increased levels of reactive oxygen species (ROS) as well as DNA damage, and both can be suppressed by anti-oxidants. Our results suggest that XPC may help repair DNA damage caused by KRAS-mediated production of ROS.
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Affiliation(s)
- Xiaoli Zhang
- Department of Pediatrics, Wells Center for Pediatrics Research, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Nonggao He
- University of Texas Medical Branch, School of Medicine Cancer Center, Galveston, TX 77550, USA
| | - Dongsheng Gu
- Department of Pediatrics, Wells Center for Pediatrics Research, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Jeff Wickliffe
- Department of Global Environmental Health Sciences, Tulane University School of Public Health, New Orleans, LA 70112, USA
| | - James Salazar
- Biology Department, Galveston College, Galveston, TX 77550, USA
| | - Istavan Boldogh
- Department of Microbiology and Immunology, University of Texas Medical Branch, School of Medicine, Galveston, TX 77550, USA
| | - Jingwu Xie
- Department of Pediatrics, Wells Center for Pediatrics Research, Indiana University School of Medicine, Indianapolis, IN 46202, USA.
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9
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The role of XPC: implications in cancer and oxidative DNA damage. Mutat Res 2011; 728:107-17. [PMID: 21763452 DOI: 10.1016/j.mrrev.2011.07.001] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2011] [Revised: 06/30/2011] [Accepted: 07/01/2011] [Indexed: 01/14/2023]
Abstract
The accumulation of DNA damage is a slow but hazardous phenomenon that may lead to cell death, accelerated aging features and cancer. One of the most versatile and important defense mechanisms against the accumulation of DNA damage is nucleotide excision repair (NER), in which the Xeroderma pigmentosum group C (XPC) protein plays a prominent role. NER can be divided into global genome repair (GG-NER) and transcription coupled repair (TC-NER). XPC is a key factor in GG-NER where it functions in DNA damage recognition and after which the repair machinery is recruited to eliminate the DNA damage. Defective XPC functioning has been shown to result in a cancer prone phenotype, in human as well as in mice. Mutation accumulation in XPC deficient mice is accelerated and increased, resulting in an increased tumor incidence. More recently XPC has also been linked to functions outside of NER since XPC deficient mice show a divergent tumor spectrum compared to other NER deficient mouse models. Multiple in vivo and in vitro experiments indicate that XPC appears to be involved in the initiation of several DNA damage-induced cellular responses. XPC seems to function in the removal of oxidative DNA damage, redox homeostasis and cell cycle control. We hypothesize that this combination of increased oxidative DNA damage sensitivity, disturbed redox homeostasis together with inefficient cell cycle control mechanisms are causes of the observed increased cancer susceptibility in oxygen exposed tissues. Such a phenotype is absent in other NER-deficient mice, including Xpa.
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10
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Preston BD, Albertson TM, Herr AJ. DNA replication fidelity and cancer. Semin Cancer Biol 2010; 20:281-93. [PMID: 20951805 PMCID: PMC2993855 DOI: 10.1016/j.semcancer.2010.10.009] [Citation(s) in RCA: 105] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2010] [Accepted: 10/07/2010] [Indexed: 12/14/2022]
Abstract
Cancer is fueled by mutations and driven by adaptive selection. Normal cells avoid deleterious mutations by replicating their genomes with extraordinary accuracy. Here we review the pathways governing DNA replication fidelity and discuss evidence implicating replication errors (point mutation instability or PIN) in carcinogenesis.
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Affiliation(s)
- Bradley D Preston
- Department of Pathology, University of Washington, Seattle, WA 98195, USA.
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11
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Animal Models of Xeroderma Pigmentosum. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2008; 637:152-60. [DOI: 10.1007/978-0-387-09599-8_17] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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12
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Niedernhofer LJ. Nucleotide excision repair deficient mouse models and neurological disease. DNA Repair (Amst) 2008; 7:1180-9. [PMID: 18272436 DOI: 10.1016/j.dnarep.2007.12.006] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2007] [Accepted: 12/12/2007] [Indexed: 11/27/2022]
Abstract
Nucleotide excision repair (NER) is a highly conserved mechanism to remove helix-distorting DNA base damage. A major substrate for NER is DNA damage caused by environmental genotoxins, most notably ultraviolet radiation. Xeroderma pigmentosum, Cockayne syndrome and trichothiodystrophy are three human diseases caused by inherited defects in NER. The symptoms and severity of these diseases vary dramatically, ranging from profound developmental delay to cancer predisposition and accelerated aging. All three syndromes include neurological disease, indicating an important role for NER in protecting against spontaneous DNA damage as well. To study the pathophysiology caused by DNA damage, numerous mouse models of NER-deficiency were generated by knocking-out genes required for NER or knocking-in disease-causing human mutations. This review explores the utility of these mouse models to study neurological disease caused by NER-deficiency.
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Affiliation(s)
- Laura J Niedernhofer
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Hillman Cancer Center, Pittsburgh, PA 15213, USA.
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13
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van der Pluijm I, Garinis GA, Brandt RMC, Gorgels TGMF, Wijnhoven SW, Diderich KEM, de Wit J, Mitchell JR, van Oostrom C, Beems R, Niedernhofer LJ, Velasco S, Friedberg EC, Tanaka K, van Steeg H, Hoeijmakers JHJ, van der Horst GTJ. Impaired genome maintenance suppresses the growth hormone--insulin-like growth factor 1 axis in mice with Cockayne syndrome. PLoS Biol 2007; 5:e2. [PMID: 17326724 PMCID: PMC1698505 DOI: 10.1371/journal.pbio.0050002] [Citation(s) in RCA: 190] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2006] [Accepted: 10/16/2006] [Indexed: 12/21/2022] Open
Abstract
Cockayne syndrome (CS) is a photosensitive, DNA repair disorder associated with progeria that is caused by a defect in the transcription-coupled repair subpathway of nucleotide excision repair (NER). Here, complete inactivation of NER in Csbm/m/Xpa−/− mutants causes a phenotype that reliably mimics the human progeroid CS syndrome. Newborn Csbm/m/Xpa−/− mice display attenuated growth, progressive neurological dysfunction, retinal degeneration, cachexia, kyphosis, and die before weaning. Mouse liver transcriptome analysis and several physiological endpoints revealed systemic suppression of the growth hormone/insulin-like growth factor 1 (GH/IGF1) somatotroph axis and oxidative metabolism, increased antioxidant responses, and hypoglycemia together with hepatic glycogen and fat accumulation. Broad genome-wide parallels between Csbm/m/Xpa−/− and naturally aged mouse liver transcriptomes suggested that these changes are intrinsic to natural ageing and the DNA repair–deficient mice. Importantly, wild-type mice exposed to a low dose of chronic genotoxic stress recapitulated this response, thereby pointing to a novel link between genome instability and the age-related decline of the somatotroph axis. Studies in mice defective in two DNA repair pathways (global NER and TCR; an animal model for Cockayne syndrome) highlight a link between aging, a failure to repair DNA lesions, and metabolic alterations. Normal metabolism routinely produces reactive oxygen species that damage DNA and other cellular components and is thought to contribute to the ageing process. Although DNA damage is typically kept in check by a variety of enzymes, several premature ageing disorders result from failure to remove damage from active genes. Patients with Cockayne syndrome (CS), a genetic mutation affecting one class of DNA repair enzymes, display severe growth retardation, neurological symptoms, and signs of premature ageing followed by an early death. Whereas mouse models for CS exhibit relatively mild deficits, we show that concomitant inactivation of a second DNA repair gene elicits severe CS pathology and ageing. Moreover, a few days after birth, these mice undergo systemic suppression of genes controlling growth, an unexpected decrease in oxidative metabolism, and an increased antioxidant response. Similar physiological changes are also triggered in normal mice by chronic exposure to DNA-damaging oxidative stress. From these findings, we conclude that DNA damage triggers a response aimed at limiting oxidative DNA damage levels (and associated tissue degeneration) to extend lifespan and promote healthy ageing. Better understanding of the ageing process will help to delineate intervention strategies to combat age-associated pathology.
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Affiliation(s)
- Ingrid van der Pluijm
- Department of Genetics, Center for Biomedical Genetics, Erasmus University Medical Center, Rotterdam, The Netherlands
| | - George A Garinis
- Department of Genetics, Center for Biomedical Genetics, Erasmus University Medical Center, Rotterdam, The Netherlands
| | - Renata M. C Brandt
- Department of Genetics, Center for Biomedical Genetics, Erasmus University Medical Center, Rotterdam, The Netherlands
| | - Theo G. M. F Gorgels
- Department of Genetics, Center for Biomedical Genetics, Erasmus University Medical Center, Rotterdam, The Netherlands
| | - Susan W Wijnhoven
- National Institute of Public Health and the Environment (RIVM), Laboratory of Toxicology, Pathology and Genetics (TOX), Bilthoven, The Netherlands
| | - Karin E. M Diderich
- Department of Genetics, Center for Biomedical Genetics, Erasmus University Medical Center, Rotterdam, The Netherlands
| | - Jan de Wit
- Department of Genetics, Center for Biomedical Genetics, Erasmus University Medical Center, Rotterdam, The Netherlands
| | - James R Mitchell
- Department of Genetics, Center for Biomedical Genetics, Erasmus University Medical Center, Rotterdam, The Netherlands
| | - Conny van Oostrom
- National Institute of Public Health and the Environment (RIVM), Laboratory of Toxicology, Pathology and Genetics (TOX), Bilthoven, The Netherlands
| | - Rudolf Beems
- National Institute of Public Health and the Environment (RIVM), Laboratory of Toxicology, Pathology and Genetics (TOX), Bilthoven, The Netherlands
| | - Laura J Niedernhofer
- Department of Genetics, Center for Biomedical Genetics, Erasmus University Medical Center, Rotterdam, The Netherlands
| | - Susana Velasco
- Laboratory of Molecular Pathology, Department of Pathology, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Errol C Friedberg
- Laboratory of Molecular Pathology, Department of Pathology, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Kiyoji Tanaka
- Division of Cellular Genetics, Institute for Molecular and Cellular Biology, Osaka University, Osaka, Japan
| | - Harry van Steeg
- National Institute of Public Health and the Environment (RIVM), Laboratory of Toxicology, Pathology and Genetics (TOX), Bilthoven, The Netherlands
| | - Jan H. J Hoeijmakers
- Department of Genetics, Center for Biomedical Genetics, Erasmus University Medical Center, Rotterdam, The Netherlands
| | - Gijsbertus T. J van der Horst
- Department of Genetics, Center for Biomedical Genetics, Erasmus University Medical Center, Rotterdam, The Netherlands
- * To whom correspondence should be addressed. E-mail:
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Nordstrand LM, Ringvoll J, Larsen E, Klungland A. Genome instability and DNA damage accumulation in gene-targeted mice. Neuroscience 2007; 145:1309-17. [PMID: 17218062 DOI: 10.1016/j.neuroscience.2006.10.059] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2006] [Revised: 10/29/2006] [Accepted: 10/30/2006] [Indexed: 01/02/2023]
Abstract
Six major pathways for DNA repair have been identified. These include (1) DNA repair by direct reversal, (2) base excision repair, (3) mismatch repair, (4) nucleotide excision repair, (5) homologous recombination, and (6) non-homologous end-joining. In addition, several other cellular processes influence the response to DNA damage. The generation of gene-targeted organisms is crucial for assessing the relative contribution of single DNA repair proteins and DNA repair pathways in maintaining genome stability. In particular, the accumulation of DNA damage, mutations and cancer in unexposed gene-targeted animals illuminates the spontaneous load of a particular lesion and the relative significance of a single gene in a specific pathway. Strategies for the generation of gene-targeted mice have been available for 15 years and more than 100 different genes relevant to DNA repair have been targeted. This review describes some important progress made toward understanding spontaneous DNA damage and its repair, exemplified through one, or a few, gene-targeted mice from each major DNA repair pathway.
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Affiliation(s)
- L M Nordstrand
- Centre for Molecular Biology and Neuroscience and Institute of Medical Microbiology, Rikshospitalet-Radiumhospitalet HF, University of Oslo, N-0027 Oslo, Norway
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15
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Ikehata H, Saito Y, Yanase F, Mori T, Nikaido O, Ono T. Frequent recovery of triplet mutations in UVB-exposed skin epidermis of Xpc-knockout mice. DNA Repair (Amst) 2007; 6:82-93. [PMID: 17049932 DOI: 10.1016/j.dnarep.2006.09.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2006] [Revised: 09/11/2006] [Accepted: 09/11/2006] [Indexed: 10/24/2022]
Abstract
Mutations of the Xpc gene cause a deficiency in global genome repair, a subpathway of nucleotide excision repair (NER), in mammalian cells. We used transgenic mice harboring the lambda-phage-based lacZ mutational reporter gene to study the effect of an Xpc null mutation (Xpc-/-) on damage induction, repair and mutagenesis in mouse skin epidermis after UVB irradiation. UVB induced equal amounts of cyclobutane pyrimidine dimers (CPDs) and pyrimidine(6-4)pyrimidone photoproducts (64PPs) in mouse skin epidermis of Xpc-/- and wild-type mice. CPDs were not significantly removed in either of the mouse genotypes by 12h after irradiation, whereas removal of 64PPs was observed in the wild-type. Irradiation with 300 and 400J/m2 UVB increased the lacZ mutant frequency in the Xpc-/- epidermis to at least twice as high as in the wild-type. Ninety-nine lacZ mutants isolated from the UVB-exposed epidermis of Xpc(-/-)mice were analyzed and compared with mutant sequences from irradiated wild-type mice. The spectra of the mutations in the two genotypes were both highly UV-specific and similar in the dominance of C-->T transitions at dipyrimidine sites; however, Xpc-/- mice had a higher frequency of two-base tandem substitutions, including CC-->TT mutations, three-base tandem substitutions and double base substitutions that were separated by one unchanged base in a three-base sequence (alternating mutations). These tandem/alternating mutations included a remarkably large number of triplet mutations, a recently reported, novel type of UV-specific mutation, characterized by multiple base substitutions or frameshifts within a three-nucleotide sequence containing a dipyrimidine. We concluded that the triplet mutation is a UV-specific mutation that preferably occurs in NER deficient genetic backgrounds.
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Affiliation(s)
- Hironobu Ikehata
- Department of Cell Biology, Graduate School of Medicine, Tohoku University, Sendai 980-8575, Japan.
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16
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Ohkumo T, Kondo Y, Yokoi M, Tsukamoto T, Yamada A, Sugimoto T, Kanao R, Higashi Y, Kondoh H, Tatematsu M, Masutani C, Hanaoka F. UV-B radiation induces epithelial tumors in mice lacking DNA polymerase eta and mesenchymal tumors in mice deficient for DNA polymerase iota. Mol Cell Biol 2006; 26:7696-706. [PMID: 17015482 PMCID: PMC1636855 DOI: 10.1128/mcb.01076-06] [Citation(s) in RCA: 95] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
DNA polymerase eta (Pol eta) is the product of the Polh gene, which is responsible for the group variant of xeroderma pigmentosum, a rare inherited recessive disease which is characterized by susceptibility to sunlight-induced skin cancer. We recently reported in a study of Polh mutant mice that Pol eta is involved in the somatic hypermutation of immunoglobulin genes, but the cancer predisposition of Polh-/- mice has not been examined until very recently. Another translesion synthesis polymerase, Pol iota, a Pol eta paralog encoded by the Poli gene, is naturally deficient in the 129 mouse strain, and the function of Pol iota is enigmatic. Here, we generated Polh Poli double-deficient mice and compared the tumor susceptibility of them with Polh- or Poli-deficient animals under the same genetic background. While Pol iota deficiency does not influence the UV sensitivity of mouse fibroblasts irrespective of Polh genotype, Polh Poli double-deficient mice show slightly earlier onset of skin tumor formation. Intriguingly, histological diagnosis after chronic treatment with UV light reveals that Pol iota deficiency leads to the formation of mesenchymal tumors, such as sarcomas, that are not observed in Polh(-/-) mice. These results suggest the involvement of the Pol eta and Pol iota proteins in UV-induced skin carcinogenesis.
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Affiliation(s)
- Tsuyoshi Ohkumo
- Cellular Biology Laboratory, Graduate School of Frontier Biosciences, Osaka University, 1-3 Yamada-oka, Suita, Osaka 565-0871, Japan
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17
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Patterson AD, Hildesheim J, Fornace AJ, Hollander MC. Neural tube development requires the cooperation of p53- and Gadd45a-associated pathways. ACTA ACUST UNITED AC 2006; 76:129-32. [PMID: 16470852 DOI: 10.1002/bdra.20217] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND Numerous genetically engineered mouse models for neural tube defects (NTDs) exist, and some of the implicated proteins are functionally related. For example, the growth arrest and DNA damage-inducible protein Gadd45a and tumor suppressor p53 are functionally similar, and both are involved in neural tube development (Gadd45a- and Trp53-null embryos show low levels of exencephaly). To assess their roles in neural tube development, we generated double-null mice from Gadd45a- and Trp53-null mice, as well as from cyclin-dependent kinase inhibitor (Cdkn1a) (p21)-null and xeroderma pigmentosum group C (XPC)-null mice that do not show spontaneous exencephaly. METHODS Gadd45a-, Trp53-, Cdkn1a-, and XPC-null mice were crossed to generate several double-null mouse models. Embryos (embryonic day [ED] 16-18) from the single- and double-null crosses were scored for NTDs. RESULTS Deletion of both Gadd45a and Trp53 in mice increased exencephaly frequencies compared to the deletion of either single gene (34.0% in Gadd45a/Trp53-null compared to 8.4% and 9.1% in the Gadd45a- and Trp53-null embryos, respectively). Furthermore, although deletion of another p53-regulated gene, Cdkn1a, is not associated with exencephaly, in conjunction with Gadd45a deletion, the exencephaly frequencies are increased (30.5% in the Gadd45a/Cdkn1a-null embryos) and are similar to those in the Gadd45a/Trp53-null embryos. Although XPC deletion increased exencephaly frequencies in Trp53-null embryos, XPC deletion did not increase the exencephaly frequencies in Gadd45a-null embryos. CONCLUSIONS The increased genetic liability to exencephaly in the Gadd45a/Trp53- and Gadd45a/Cdkn1a-null embryos may be related to the disruption of multiple cellular pathways associated with Gadd45a and p53.
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Affiliation(s)
- Andrew D Patterson
- National Institutes of Health-George Washington University Graduate Partnerships Program in Genetics, National Cancer Institute, National Institutes of Health, Bethesda, MD 20889, USA
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18
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Tsai PS, Nielen M, van der Horst GTJ, Colenbrander B, Heesterbeek JAP, van Vlissingen JMF. The Effect of DNA Repair Defects on Reproductive Performance in Nucleotide Excision Repair (NER) Mouse Models: An Epidemiological Approach. Transgenic Res 2005; 14:845-57. [PMID: 16315091 DOI: 10.1007/s11248-005-1772-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2005] [Accepted: 08/05/2005] [Indexed: 10/25/2022]
Abstract
In this study, we used an epidemiological approach to analyze an animal database of DNA repair deficient mice on reproductive performance in five Nucleotide Excision Repair (NER) mutant mouse models on a C57BL/6 genetic background, namely CSA, CSB, XPA, XPC [models for the human DNA repair disorders Cockayne Syndrome (CS) and xeroderma pigmentosum (XP), respectively] and mHR23B (not associated with human disease). This approach allowed us to detect and quantify reproductive effects based on a relatively small number of matings. We measured and quantified the scale of the effect between factors that might influence reproductive performance (i.e. age at co-housing, seasons) and reproductive parameters (i.e. litter size and pairing-to-birth interval -'pbi'). Besides, we detected and quantified the differences in reproductive performance between wild type mice and heterozygous/homozygous NER mutant mice. From our analyses, we found impaired reproduction in heterozygous and homozygous knock out mice; in particular, reduced litter size and lengthened pbi was related to the NER mutation-mHR23B, in heterozygous couples, even if they were otherwise phenotypically normal. Heterozygous mHR23B couples produced a 6.6-fold lower number of mHR23B(-/-) pups than indicated by Mendelian expectation; other genetic deficiencies studied were not statistically significant from each other or wild type controls. We concluded that careful epidemiological evaluations by analysis of animal database could provide reliable information on reproductive performance and detect deviations that would remain unnoticed without this. Also, some managerial aspects of mouse breeding could be evaluated.
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Affiliation(s)
- P S Tsai
- Department of Farm Animal Health, Faculty of Veterinary Medicine, Utrecht University, The Netherlands
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19
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Friedberg EC, Meira LB. Database of mouse strains carrying targeted mutations in genes affecting biological responses to DNA damage Version 7. DNA Repair (Amst) 2005; 5:189-209. [PMID: 16290067 DOI: 10.1016/j.dnarep.2005.09.009] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2005] [Revised: 09/13/2005] [Accepted: 09/13/2005] [Indexed: 01/23/2023]
Abstract
We present Version 7 of a database of mouse mutant strains that affect biological responses to DNA damage. This database is also electronically available at http://pathcuricl.swmed.edu/research/research.htm.
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Affiliation(s)
- Errol C Friedberg
- Laboratory of Molecular Pathology, Department of Pathology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390-9072, USA.
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20
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He Z, Li J, Zhen C, Feng L, Ding X. Knockdown of p53 by RNAi in ES cells facilitates RA-induced differentiation into muscle cells. Biochem Biophys Res Commun 2005; 335:676-83. [PMID: 16087156 DOI: 10.1016/j.bbrc.2005.07.129] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2005] [Accepted: 07/25/2005] [Indexed: 01/12/2023]
Abstract
The p53 gene is widely expressed in embryo, tissues, and tumors, and its deficiency can rescue embryonic defects in certain genes null embryos. However, it is still poorly understood whether p53 is involved in myoblast and neuronal fate determination during embryogenesis. We established the ES cell clone in which p53 protein was persistently suppressed by stable expression of p53 RNAi, and GFP was expressed in a p53 RNAi transcription-independent manner. With the classical protocol in which the differentiation of ES cells into either neural or muscle cell is specifically modulated by different dosage retinoic acid (RA), we evaluated the function of p53 during myoblast and neuronal commitment. With RA treatment, silencing of p53 by RNAi in ES cells leads to dominant muscle cell production but lack of neuronal cell, indicating that p53 indeed plays a role during muscle and neuronal fate commitment. It thus provides a good model for investigating cross-talk between RA and p53 pathways during myogenesis and neurogenesis from ES cells.
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Affiliation(s)
- Zhao He
- Laboratory of Molecular and Cell biology, Institute of Biochemistry and Cell Biology, Shanghai 200031, China
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21
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Niimi N, Sugo N, Aratani Y, Koyama H. Genetic interaction between DNA polymerase beta and DNA-PKcs in embryogenesis and neurogenesis. Cell Death Differ 2005; 12:184-91. [PMID: 15647757 DOI: 10.1038/sj.cdd.4401543] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
DNA polymerase beta (Polbeta) has been implicated in base excision repair. Polbeta knockout mice exhibit apoptosis in postmitotic neuronal cells and die at birth. Also, mice deficient in nonhomologous end-joining (NHEJ), a major pathway for DNA double-strand break repair, cause massive neuronal apoptosis. Severe combined immunodeficiency (SCID) mice have a mutation in the gene encoding DNA-dependent protein kinase catalytic subunit (DNA-PKcs), the component of NHEJ, and exhibit defective lymphogenesis. To study the interaction between Polbeta and DNA-PKcs, we generated mice doubly deficient in Polbeta and DNA-PKcs. Polbeta(-/-)DNA-PKcs(scid/scid) embryos displayed greater developmental delay, more extensive neuronal apoptosis, and earlier lethality than Polbeta(-/-) and DNA-PKcs(scid/scid) embryos. Furthermore, to study the involvement of p53 in the phenotype, we generated Polbeta(-/-)DNA-PKcs(scid/scid)p53(-/-) triple-mutant mice. The mutants did not exhibit apoptosis but were lethal with defective neurulation at midgestation. These results suggest a genetic interaction between Polbeta and DNA-PKcs in embryogenesis and neurogenesis.
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Affiliation(s)
- N Niimi
- Kihara Institute for Biological Research and Graduate School of Integrated Science, Yokohama City University, 641-12 Maioka-cho, Totsuka-ku, Yokohama 244-0813, Japan
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22
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Hollander MC, Philburn RT, Patterson AD, Velasco-Miguel S, Friedberg EC, Linnoila RI, Fornace AJ. Deletion of XPC leads to lung tumors in mice and is associated with early events in human lung carcinogenesis. Proc Natl Acad Sci U S A 2005; 102:13200-5. [PMID: 16141330 PMCID: PMC1201581 DOI: 10.1073/pnas.0503133102] [Citation(s) in RCA: 105] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Chromosome 3p and 1p deletions are among the most frequent genetic changes in human lung cancer and although candidate tumor suppressor genes have been identified in these regions, no causative correlations have been drawn between deletion or mutation of these and lung carcinogenesis. We identify XPC and Gadd45a as genes within each of these regions involved in lung tumor initiation and progression, respectively. One hundred percent of XPC-/- mice develop multiple spontaneous lung tumors with a minority progressing to non-small cell lung adenocarcinoma, occasionally with metastasis to adjacent lymph nodes. Deletion of Gadd45a alone does not lead to increased lung tumors in mice, but coupled with an XPC deletion, it results in lung tumor progression. Analysis of published data indicated allelic loss of XPC in most human lung tumors and allelic loss of Gadd45a in some human lung and other cancer types. Because DNA repair capacity is compromised in XPC+/- cells, it is possible that the loss of a single XPC allele in the human lung might confer a mutator phenotype. Coupled with cigarette carcinogens, decreased DNA repair would lead to additional mutations in genes such as p53 that are frequent targets in lung cancer.
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23
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van Oosten M, Stout GJ, Backendorf C, Rebel H, de Wind N, Darroudi F, van Kranen HJ, de Gruijl FR, Mullenders LH. Mismatch repair protein Msh2 contributes to UVB-induced cell cycle arrest in epidermal and cultured mouse keratinocytes. DNA Repair (Amst) 2005; 4:81-9. [PMID: 15533840 DOI: 10.1016/j.dnarep.2004.08.008] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2004] [Accepted: 08/18/2004] [Indexed: 12/01/2022]
Abstract
Nucleotide excision repair (NER), cell cycle regulation and apoptosis are major defence mechanisms against the carcinogenic effects of UVB radiation. NER eliminates UVB-induced DNA photolesions via two subpathways: global genome repair (GGR) and transcription-coupled repair (TCR). In a previous study, we found UVB-induced accumulation of tetraploid (4N) keratinocytes in the epidermis of Xpc(-/-) mice (no GGR), but not in Xpa(-/-) (no TCR and no GGR) or in wild-type (WT) mice. We inferred that this arrest in Xpc(-/-) mice is caused by erroneous replication past photolesions, leading to 'compound lesions' known to be recognised by mismatch repair (MMR). MMR-induced futile cycles of breakage and resynthesis at sites of compound lesions may then sustain a cell cycle arrest. The present experiments with Xpc(-/-)Msh2(-/-) mice and derived keratinocytes show that the MMR protein Msh2 indeed plays a role in the generation of the UVB-induced arrested cells: a Msh2-deficiency lowered significantly the percentage of arrested cells in vivo (40-50%) and in vitro (30-40%). Analysis of calyculin A (CA)-induced premature chromosome condensation (PCC) of cultured Xpc(-/-) keratinocytes showed that the delayed arrest occurred in late S phase rather than in G(2)-phase. Taken together, the results indicate that in mouse epidermis and cultured keratinocytes, the MMR protein Msh2 plays a role in the UVB-induced S-phase arrest. This indicates that MMR plays a role in the UVB-induced S-phase arrest. Alternatively, Msh2 may have a more direct signalling function.
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Affiliation(s)
- Marijke van Oosten
- Department of Toxicogenetics, Leiden University Medical Center, Wassenaarseweg 72, 2333 AL Leiden, The Netherlands
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24
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Hoogervorst EM, van Oostrom CTM, Beems RB, van Benthem J, van den Berg J, van Kreijl CF, Vos JG, de Vries A, van Steeg H. 2-AAF-induced tumor development in nucleotide excision repair-deficient mice is associated with a defect in global genome repair but not with transcription coupled repair. DNA Repair (Amst) 2005; 4:3-9. [PMID: 15533832 DOI: 10.1016/j.dnarep.2004.08.009] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2004] [Indexed: 11/24/2022]
Abstract
The nucleotide excision repair (NER) pathway comprises two sub-pathways, transcription coupled repair (TCR) and global genome repair (GGR). To establish the importance of these separate sub-pathways in tumor suppression, we exposed mice deficient for either TCR (Csb), GGR (Xpc) or both (Xpa) to 300 ppm 2-acetylaminofluorene (in feed, ad libitum) in a unique comparative exposure experiment. We found that cancer proneness was directly linked to a defect in the GGR pathway of NER as both Xpa and Xpc mice developed significantly more liver tumors upon 2-AAF exposure than wild type or Csb mice. In contrast, a defect in TCR appeared to act tumor suppressive, leading to a lower hepatocellular tumor response in Xpa mice (tumor incidence of 25%) as compared to Xpc mice (53% tumor-bearing mice). The link between deficient GGR and tumor proneness was most pronounced in the liver, but this phenomenon was also found in the urinary bladder. As tumor induction by 2-AAF appeared almost exclusively dependent on a defect in GGR, we examined whether gene mutation induction in the non-transcribed lacZ locus could reliably predict tumor risk. Interestingly, however, short-term 2-AAF exposure induced lacZ mutant levels in Csb mice almost as high as those found in Xpa or Xpc mice. This indicates that lacZ mutant frequencies are not correlated with a specific DNA repair defect and eventual tumor outcome, at least not in the experimental design presented here.
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Affiliation(s)
- Esther M Hoogervorst
- Laboratory of Toxicology, Pathology and Genetics, National Institute of Public Health and the Environment, P.O. Box 1, 3720 BA Bilthoven, The Netherlands
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25
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Friedberg EC, Meira LB. Database of mouse strains carrying targeted mutations in genes affecting biological responses to DNA damage (Version 6). DNA Repair (Amst) 2005; 3:1617-38. [PMID: 15474422 DOI: 10.1016/j.dnarep.2004.06.016] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/25/2004] [Indexed: 12/31/2022]
Abstract
We present Version 6 of a database of mouse mutant strains that affect biological responses to DNA damage. This database is also electronically available at http://pathcuric1.swmed.edu/research/research.htm.
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Affiliation(s)
- Errol C Friedberg
- Laboratory of Molecular Pathology, Department of Pathology, University of Texas Southwestern Medical Center, Dallas, TX 75390-9072, USA.
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26
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Nahari D, McDaniel LD, Task LB, Daniel RL, Velasco-Miguel S, Friedberg EC. Mutations in the Trp53 gene of UV-irradiated Xpc mutant mice suggest a novel Xpc-dependent DNA repair process. DNA Repair (Amst) 2004; 3:379-86. [PMID: 15010313 DOI: 10.1016/j.dnarep.2003.03.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/03/2003] [Indexed: 01/06/2023]
Abstract
Mutational hot spots in the human p53 gene are well established in tumors in the human population and are frequently negative prognosticators of the clinical outcome. We previously developed a mouse model of skin cancer with mutations in the xeroderma pigmentosum group C gene (Xpc). UVB radiation-induced skin cancer is significantly enhanced in these mice when they also carry a mutation in one copy of the Trp53 gene (Xpc-/-Trp53+/-). Skin tumors in these mice often contain inactivating mutations in the remaining Trp53 allele and we have previously reported a novel mutational hot spot at a non-dipyrimidine site (ACG) in codon 122 of the Trp53 gene in the tumors. Here we show that this mutation is not a hot spot in Xpa or Csa mutant mice. Furthermore, the mutation in codon T122 can be identified in mouse skin DNA from (Xpc-/-Trp53+/-) mice as early as 2 weeks after exposure to UVB radiation, well before histological evidence of dysplastic or neoplastic changes. Since this mutational hot spot is not at a dipyrimidine site and is apparently Xpc-specific, we suggest that some form of non-dipyrimidine base damage is normally repaired in a manner that is distinct from conventional nucleotide excision repair, but that requires XPC protein.
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Affiliation(s)
- Dorit Nahari
- Laboratory of Molecular Pathology, Department of Pathology, University of Texas, Southwestern Medical Center, Dallas, TX 75390-9072, USA
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27
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Velasco-Miguel S, Richardson JA, Gerlach VL, Lai WC, Gao T, Russell LD, Hladik CL, White CL, Friedberg EC. Constitutive and regulated expression of the mouse Dinb (Polkappa) gene encoding DNA polymerase kappa. DNA Repair (Amst) 2003; 2:91-106. [PMID: 12509270 DOI: 10.1016/s1568-7864(02)00189-1] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A recently discovered group of novel polymerases are characterized by significantly reduced fidelity of DNA synthesis in vitro. This feature is consistent with the relaxed fidelity required for the replicative bypass of various types of base damage that frequently block high fidelity replicative polymerases. The present studies demonstrate that the specialized DNA polymerase kappa (polkappa) is uniquely and preferentially expressed in the adrenal cortex and testis of the mouse, as well as in a variety of other tissues. The adrenal cortex is the sole site of detectable expression of the Polkappa gene in mouse embryos. This adrenal expression pattern is consistent with a requirement for polkappa for the replicative bypass of DNA base damage generated during steroid biosynthesis. The expression pattern of polkappa in the testis is specific for particular stages of spermatogenesis and is distinct from the expression pattern of several other low fidelity DNA polymerases that are also expressed during spermatogenesis. The mouse (but not the human) Polkappa gene is primarily regulated by the p53 gene and is upregulated in response to exposure to various DNA-damaging agents in a p53-dependent manner.
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Affiliation(s)
- Susana Velasco-Miguel
- Department of Pathology, University of Texas Southwestern Medical Center, Dallas, TX 73590-9013, USA
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28
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Meira LB, Cheo DL, Reis AM, Claij N, Burns DK, te Riele H, Friedberg EC. Mice defective in the mismatch repair gene Msh2 show increased predisposition to UVB radiation-induced skin cancer. DNA Repair (Amst) 2002; 1:929-34. [PMID: 12531020 DOI: 10.1016/s1568-7864(02)00143-x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Mice defective in the mismatch repair (MMR) gene Msh2 manifest an enhanced predisposition to skin cancer associated with exposure to UVB radiation. This predisposition is further heightened if the mice are additionally defective for the nucleotide excision repair gene Xpc. To test the hypothesis that the predisposition of Msh2 mutant mice to skin cancer reflects a mutator phenotype associated with increased proliferation of skin cells following exposure to UV radiation, Msh2 mutant mice were exposed to the tumor promoter TPA. Such mice showed a robust proliferative response in the skin, but did not manifest evidence of dysplasia or neoplasia. We conclude that the predisposition of Msh2 mice to UVB radiation-induced skin cancer reflects an interaction between the processes of mismatch repair and some other excision repair mode, the exact nature of which remains to be established.
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Affiliation(s)
- Lisiane B Meira
- Laboratory of Molecular Pathology, Department of Pathology, Southwestern Medical Center, University of Texas, Dallas, TX 75235, USA
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29
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Schul W, Jans J, Rijksen YM, Klemann KH, Eker AP, de Wit J, Nikaido O, Nakajima S, Yasui A, Hoeijmakers JH, van der Horst GT. Enhanced repair of cyclobutane pyrimidine dimers and improved UV resistance in photolyase transgenic mice. EMBO J 2002; 21:4719-29. [PMID: 12198174 PMCID: PMC125407 DOI: 10.1093/emboj/cdf456] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
During evolution, placental mammals appear to have lost cyclobutane pyrimidine dimer (CPD) photolyase, an enzyme that efficiently removes UV-induced CPDs from DNA in a light-dependent manner. As a consequence, they have to rely solely on the more complex, and for this lesion less efficient, nucleotide excision repair pathway. To assess the contribution of poor repair of CPDs to various biological effects of UV, we generated mice expressing a marsupial CPD photolyase transgene. Expression from the ubiquitous beta-actin promoter allowed rapid repair of CPDs in epidermis and dermis. UV-exposed cultured dermal fibroblasts from these mice displayed superior survival when treated with photoreactivating light. Moreover, photoreactivation of CPDs in intact skin dramatically reduced acute UV effects like erythema (sunburn), hyperplasia and apoptosis. Mice expressing the photolyase from keratin 14 promoter photo reactivate CPDs in basal and early differentiating keratinocytes only. Strikingly, in these animals, the anti-apoptotic effect appears to extend to other skin compartments, suggesting the presence of intercellular apoptotic signals. Thus, providing mice with CPD photolyase significantly improves repair and uncovers the biological effects of CPD lesions.
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Affiliation(s)
| | | | | | | | | | | | - Osamu Nikaido
- MGC, Department of Cell Biology and Genetics, Center for Biomedical Genetics, Erasmus University Rotterdam, PO Box 1738, 3000 DR Rotterdam, The Netherlands,
Division of Radiation Biology, Faculty of Pharmaceutical Sciences, Kanazawa University, Kanazawa 920-0934 and Department of Molecular Genetics, Institute of Development, Aging and Cancer, Tohoku University, Sendai 980-8575, Japan Corresponding author e-mail: W.Schul and J.Jans contributed equally to this work
| | - Satoshi Nakajima
- MGC, Department of Cell Biology and Genetics, Center for Biomedical Genetics, Erasmus University Rotterdam, PO Box 1738, 3000 DR Rotterdam, The Netherlands,
Division of Radiation Biology, Faculty of Pharmaceutical Sciences, Kanazawa University, Kanazawa 920-0934 and Department of Molecular Genetics, Institute of Development, Aging and Cancer, Tohoku University, Sendai 980-8575, Japan Corresponding author e-mail: W.Schul and J.Jans contributed equally to this work
| | - Akira Yasui
- MGC, Department of Cell Biology and Genetics, Center for Biomedical Genetics, Erasmus University Rotterdam, PO Box 1738, 3000 DR Rotterdam, The Netherlands,
Division of Radiation Biology, Faculty of Pharmaceutical Sciences, Kanazawa University, Kanazawa 920-0934 and Department of Molecular Genetics, Institute of Development, Aging and Cancer, Tohoku University, Sendai 980-8575, Japan Corresponding author e-mail: W.Schul and J.Jans contributed equally to this work
| | | | - Gijsbertus T.J. van der Horst
- MGC, Department of Cell Biology and Genetics, Center for Biomedical Genetics, Erasmus University Rotterdam, PO Box 1738, 3000 DR Rotterdam, The Netherlands,
Division of Radiation Biology, Faculty of Pharmaceutical Sciences, Kanazawa University, Kanazawa 920-0934 and Department of Molecular Genetics, Institute of Development, Aging and Cancer, Tohoku University, Sendai 980-8575, Japan Corresponding author e-mail: W.Schul and J.Jans contributed equally to this work
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30
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Ng JMY, Vrieling H, Sugasawa K, Ooms MP, Grootegoed JA, Vreeburg JTM, Visser P, Beems RB, Gorgels TGMF, Hanaoka F, Hoeijmakers JHJ, van der Horst GTJ. Developmental defects and male sterility in mice lacking the ubiquitin-like DNA repair gene mHR23B. Mol Cell Biol 2002; 22:1233-45. [PMID: 11809813 PMCID: PMC134644 DOI: 10.1128/mcb.22.4.1233-1245.2002] [Citation(s) in RCA: 85] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
mHR23B encodes one of the two mammalian homologs of Saccharomyces cerevisiae RAD23, a ubiquitin-like fusion protein involved in nucleotide excision repair (NER). Part of mHR23B is complexed with the XPC protein, and this heterodimer functions as the main damage detector and initiator of global genome NER. While XPC defects exist in humans and mice, mutations for mHR23A and mHR23B are not known. Here, we present a mouse model for mHR23B. Unlike XPC-deficient cells, mHR23B(-/-) mouse embryonic fibroblasts are not UV sensitive and retain the repair characteristics of wild-type cells. In agreement with the results of in vitro repair studies, this indicates that mHR23A can functionally replace mHR23B in NER. Unexpectedly, mHR23B(-/-) mice show impaired embryonic development and a high rate (90%) of intrauterine or neonatal death. Surviving animals display a variety of abnormalities, including retarded growth, facial dysmorphology, and male sterility. Such abnormalities are not observed in XPC and other NER-deficient mouse mutants and point to a separate function of mHR23B in development. This function may involve regulation of protein stability via the ubiquitin/proteasome pathway and is not or only in part compensated for by mHR23A.
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Affiliation(s)
- Jessica M Y Ng
- MGC-Department of Cell Biology and Genetics, Centre for Biomedical Genetics, Erasmus University Rotterdam, Rotterdam, The Netherlands
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31
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Termorshuizen F, Garssen J, Norval M, Koulu L, Laihia J, Leino L, Jansen CT, De Gruijl F, Gibbs NK, De Simone C, Van Loveren H. A review of studies on the effects of ultraviolet irradiation on the resistance to infections: evidence from rodent infection models and verification by experimental and observational human studies. Int Immunopharmacol 2002; 2:263-75. [PMID: 11811930 DOI: 10.1016/s1567-5769(01)00178-3] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Recent studies on the immunosuppressive effects of ultraviolet radiation (UVR) and the related resistance to infections in rodents and humans are presented. The waveband dependency of trans-to-cis isomerisation of urocanic acid in the stratum corneum and the role of DNA damage in UVR-induced erythema and immunosuppression were investigated to further elucidate the underlying mechanisms. Furthermore, human experimental studies on UVR-induced immunomodulation were performed. It appeared that the doses needed to suppress various immune parameters in humans (e.g. NK activity, contact hypersensitivity) were higher than those needed in experiments in rodents. Still, extrapolation of experimental animal data to the human situation showed that UVR may impair the resistance to different systemic infections at relevant outdoor doses. In observational human studies we aimed to substantiate the relevance of UVR for infections in humans. It was shown that sunny season was associated with a slightly retarded but clinically non-relevant antibody response to hepatitis B vaccination. Furthermore, sunny season appeared to be associated with a small decline in the number of CD4+ T-helper cells in a cohort of HIV-infected persons and a higher recurrence of herpes simplex and herpes zoster in a cohort of renal transplant recipients. However, in a study among young children a higher exposure to solar UVR was associated with a lower occurrence of upper respiratory tract symptoms. As disentangling the effects of UVR from other relevant factors is often impossible in observational studies, concise quantitative risk estimations for the human situation cannot be given at present.
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Affiliation(s)
- F Termorshuizen
- Laboratory for Pathology and Immunobiology, National Institute of Public Health and the Environment, Bilthoven, The Netherlands
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32
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Meira LB, Reis AM, Cheo DL, Nahari D, Burns DK, Friedberg EC. Cancer predisposition in mutant mice defective in multiple genetic pathways: uncovering important genetic interactions. Mutat Res 2001; 477:51-8. [PMID: 11376686 DOI: 10.1016/s0027-5107(01)00097-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Mouse models that mimic the human skin cancer-prone disease xeroderma pigmentosum (XP) provide an useful experimental system with which to study the relationship between the DNA repair process of nucleotide excision repair (NER) and ultraviolet- (UV) induced skin carcinogenesis. We have generated Xpc mutant mice and documented their deficiency in the process of NER of UV-induced DNA damage. Xpc mutant mice are highly predisposed to UV-B radiation-induced skin cancer, both in the homozygous and the heterozygous state. The combination of Xpc and Trp53 mutations enhances this predisposition and alters the tumor spectrum observed in single mutant mice. These results suggest a synergism between NER and the function of Trp53 in suppression of cancer. We have examined the mutational spectrum in the Trp53 gene from skin cancers in Trp53+/+ and Trp53+/- mice of all three Xpc genotypes and have found evidence for signature mutations associated with defective NER. In addition, we have demonstrated that Xpc mutant mice are highly predisposed to the induction of lung and liver cancers by treatment with 2-acetylaminofluorene (2-AAF) and N-OH-2-AAF. By combining the Xpc mutation with other mutations in genes involved in repair of DNA damage we have identified additional genetic interactions important in carcinogenesis. The mouse Apex gene is a critical component of the base excision repair (BER) pathway as well as the redox regulation of transcription factors important in growth control and the cellular response to DNA damage. By combining mutations in Xpc, Trp53 and Apex we have obtained genetic evidence for a functional interaction between Apex and Trp53 which probably involves the activation of the Trp53 protein by Apex. Mutations in the mismatch repair (MMR) gene Msh2 also influence the carcinogenesis observed in Xpc Trp53 mutant mice. Our results demonstrate that multiple repair pathways operate in prevention of tumor formation.
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Affiliation(s)
- L B Meira
- Laboratory of Molecular Pathology, Department of Pathology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
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33
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Berneburg M, Lehmann AR. Xeroderma pigmentosum and related disorders: defects in DNA repair and transcription. ADVANCES IN GENETICS 2001; 43:71-102. [PMID: 11037299 DOI: 10.1016/s0065-2660(01)43004-5] [Citation(s) in RCA: 155] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The genetic disorders xeroderma pigmentosum (XP), Cockayne syndrome (CS), and trichothiodystrophy (TTD) are all associated with defects in nucleotide excision repair (NER) of DNA damage. Their clinical features are very different, however, XP being a highly cancer-prone skin disorder, whereas CS and TTD are cancer-free multisystem disorders. All three are genetically complex, with at least eight complementation groups for XP (XP-A to -G and variant), five for CS (CS-A, CS-B, XP-B, XP-D, and XP-G), and three for TTD (XP-B, XP-D, and TTD-A). With the exception of the variant, the products of the XP genes are proteins involved in the different steps of NER, and comprise three damage-recognition proteins, two helicases, and two nucleases. The two helicases, XPB and XPD, are components of the basal transcription factor TFIIH, which has a dual role in NER and initiation of transcription. Different mutations in these genes can affect NER and transcription differentially, and this accounts for the different clinical phenotypes. Mutations resulting in defective repair without affecting transcription result in XP, whereas if transcription is also affected, TTD is the outcome. CS proteins are only involved in transcription-coupled repair, a subpathway of NER in which damage in the transcribed strands of active genes is rapidly and preferentially repaired. Current evidence suggests that they also have an important but not essential role in transcription. The variant form of XP is defective in a novel DNA polymerase, which is able to synthesise DNA past UV-damaged sites.
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Affiliation(s)
- M Berneburg
- MRC Cell Mutation Unit, University of Sussex, Falmer, Brighton, United Kingdom
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34
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van Oosten M, Rebel H, Friedberg EC, van Steeg H, van der Horst GT, van Kranen HJ, Westerman A, van Zeeland AA, Mullenders LH, de Gruijl FR. Differential role of transcription-coupled repair in UVB-induced G2 arrest and apoptosis in mouse epidermis. Proc Natl Acad Sci U S A 2000; 97:11268-73. [PMID: 11005836 PMCID: PMC17189 DOI: 10.1073/pnas.200226697] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Nucleotide excision repair (NER), apoptosis, and cell-cycle regulation are major defense mechanisms against the carcinogenic effects of UVB light. NER eliminates UVB-induced DNA photolesions via two subpathways: global genome repair (GGR) and transcription-coupled repair (TCR). Defects in NER result in the human disorders xeroderma pigmentosum (XP) and Cockayne syndrome (CS), displaying severe UV sensitivity and in the case of XP, cancer proneness. We investigated the impact of deficiencies in NER subpathways on apoptosis, hyperplasia, and cell cycle progression in the epidermis of UVB-exposed CS group B (Csb(-/-)) mice (no TCR), XP group C (Xpc(-/-)) mice (no GGR), and XP group A (Xpa(-/-)) mice (no TCR and no GGR). On UVB treatment (250 J/m(2)), Xpa(-/-) and Csb(-/-) mice revealed an extensive apoptotic response in the skin, a blockage of cell cycle progression of epidermal cells, and strong hyperplasia. Interestingly, the absence of this apoptotic response in the skin of wild-type and Xpc(-/-) mice coincided with the ability of epidermal cells to enter the S phase. However, only epidermal cells of Xpc(-/-) mice subsequently became arrested in the G(2) phase. Our data demonstrate that TCR (and/or restoration of UVB-inhibited transcription) enables damaged cells to progress through S phase and prevents the induction of apoptosis and hyperplasia. G(2) arrest is manifest only under conditions of proficient TCR in combination with deficient GGR, indicating that epidermal cells become arrested in the G(2) phase as a result of persisting damage in their genome.
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Affiliation(s)
- M van Oosten
- Department of Radiation Genetics and Chemical Mutagenesis MGC, Leiden University Medical Center, 2333 AL Leiden, The Netherlands
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35
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Friedberg EC. Rous-Whipple Award Lecture. Nucleotide excision repair and cancer predisposition: A journey from man to yeast to mice. THE AMERICAN JOURNAL OF PATHOLOGY 2000; 157:693-701. [PMID: 10980107 PMCID: PMC1885695 DOI: 10.1016/s0002-9440(10)64581-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 05/18/2000] [Indexed: 01/21/2023]
Affiliation(s)
- E C Friedberg
- Laboratory of Molecular Pathology, Department of Pathology, The University of Texas Southwestern Medical Center, Dallas, Texas 75390-9072, USA.
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36
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Garssen J, van Steeg H, de Gruijl F, de Boer J, van der Horst GT, van Kranen H, van Loveren H, van Dijk M, Fluitman A, Weeda G, Hoeijmakers JH. Transcription-coupled and global genome repair differentially influence UV-B-induced acute skin effects and systemic immunosuppression. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2000; 164:6199-205. [PMID: 10843671 DOI: 10.4049/jimmunol.164.12.6199] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Exposure to UV-B radiation impairs immune responses in mammals by inhibiting especially Th1-mediated contact hypersensitivity and delayed-type hypersensitivity. Immunomodulation is not restricted to the exposed skin, but is also observed at distant sites, indicating the existence of mediating factors such as products from exposed skin cells or photoactivated factors present in the superficial layers. DNA damage appears to play a key role, because enhanced nucleotide excision repair (NER) strongly counteracts immunosuppression. To determine the effects of the type and genomic location of UV-induced DNA damage on immunosuppression and acute skin reactions (edema and erythema) four congenic mouse strains carrying different defects in NER were compared: CSB and XPC mice lacking transcription-coupled or global genome NER, respectively, as well as XPA and TTD/XPD mice carrying complete or partial defects in both NER subpathways, respectively. The major conclusions are that 1) transcription-coupled DNA repair is the dominant determinant in protection against acute skin effects; 2) systemic immunomodulation is only affected when both NER subpathways are compromised; and 3) sunburn is not related to UV-B-induced immunosuppression.
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MESH Headings
- Animals
- Cockayne Syndrome/genetics
- Cockayne Syndrome/immunology
- DNA Repair/immunology
- DNA Repair/radiation effects
- Dermatitis, Contact/genetics
- Dermatitis, Contact/immunology
- Dose-Response Relationship, Immunologic
- Dose-Response Relationship, Radiation
- Edema/genetics
- Edema/immunology
- Erythema/genetics
- Erythema/immunology
- Genome
- Hair Diseases/genetics
- Hair Diseases/immunology
- Hypersensitivity, Delayed/genetics
- Hypersensitivity, Delayed/immunology
- Hypersensitivity, Delayed/microbiology
- Immunosuppression Therapy
- Listeria monocytogenes/immunology
- Listeria monocytogenes/radiation effects
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Mice, Transgenic
- Picryl Chloride/immunology
- Skin/immunology
- Skin/metabolism
- Skin/radiation effects
- Transcription, Genetic/immunology
- Transcription, Genetic/radiation effects
- Ultraviolet Rays
- Xeroderma Pigmentosum/genetics
- Xeroderma Pigmentosum/immunology
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Affiliation(s)
- J Garssen
- Laboratory for Pathology and Immunobiology and Laboratory of Health Effects Research, National Institute of Public Health and the Environment, Bilthoven, The Netherlands.
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37
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Friedberg EC, Meira LB. Database of mouse strains carrying targeted mutations in genes affecting cellular responses to DNA damage. Version 4. Mutat Res 2000; 459:243-74. [PMID: 10844240 DOI: 10.1016/s0921-8777(00)00006-9] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Affiliation(s)
- E C Friedberg
- Department of Pathology, University of Texas Southwestern Medical Center Dallas, TX 75235-9072, USA.
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38
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Friedberg EC, Bond JP, Burns DK, Cheo DL, Greenblatt MS, Meira LB, Nahari D, Reis AM. Defective nucleotide excision repair in xpc mutant mice and its association with cancer predisposition. Mutat Res 2000; 459:99-108. [PMID: 10725660 DOI: 10.1016/s0921-8777(99)00068-3] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Mice that are genetically engineered are becoming increasingly more powerful tools for understanding the molecular pathology of many human hereditary diseases, especially those that confer an increased predisposition to cancer. We have generated mouse strains defective in the Xpc gene, which is required for nucleotide excision repair (NER) of DNA. Homozygous mutant mice are highly prone to skin cancer following exposure to UVB radiation, and to liver and lung cancer following exposure to the chemical carcinogen acetylaminofluorene (AAF). Skin cancer predisposition is significantly augmented when mice are additionally defective in Trp53 (p53) gene function. We also present the results of studies with mice that are heterozygous mutant in the Apex (Hap1, Ref-1) gene required for base excision repair and with mice that are defective in the mismatch repair gene Msh2. Double and triple mutant mice mutated in multiple DNA repair genes have revealed several interesting overlapping roles of DNA repair pathways in the prevention of mutation and cancer.
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Affiliation(s)
- E C Friedberg
- Laboratory of Molecular Pathology, Department of Pathology, University of Texas Southwestern Medical Center, Dallas, TX, USA.
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39
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Ananthaswamy HN, Ouhtit A, Evans RL, Gorny A, Khaskina P, Sands AT, Conti CJ. Persistence of p53 mutations and resistance of keratinocytes to apoptosis are associated with the increased susceptibility of mice lacking the XPC gene to UV carcinogenesis. Oncogene 1999; 18:7395-8. [PMID: 10602497 DOI: 10.1038/sj.onc.1203147] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Like xeroderma pigmentosum (XP) patients, transgenic mice lacking nucleotide excision repair (NER) genes such as XPA and XPC are extremely susceptible to ultraviolet (UV)-induced skin cancer. Because the p53 gene is an important target for UV carcinogenesis and because the p53 protein modulates NER, we investigated the consequences of NER deficiency on UV-induced p53 mutations in XPC-/- mouse skin tumors. Thirty-eight (76%) of 50 UV-induced XPC-/- skin tumor analysed displayed C-->T or CC-->TT transitions at dipyrimidine sites on the untranscribed strand of the p53 gene. A major hot spot for p53 mutation occurred at codon 270, which is also a hot spot in UV-induced skin tumors from NER-proficient C3H and SKH-hr 1 mice. Interestingly, codon 270 mutations were induced in both XPC-/- and +/+ mouse skin after 1 week of UV irradiation, but the mutations persisted only in XPC-/- mouse skin after 3 - 4 weeks of chronic UV. The persistence of UV-induced p53 mutations in XPC-/- mouse skin was associated with decreased apoptosis and increased proliferation of keratinocytes, suggesting that these events may contribute to the accelerated development of UV-induced skin tumors in XPC-/- mice.
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Affiliation(s)
- H N Ananthaswamy
- Department of Immunology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd., Houston, Texas, TX 77030, USA
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40
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Jiang W, Ananthaswamy HN, Muller HK, Kripke ML. p53 protects against skin cancer induction by UV-B radiation. Oncogene 1999; 18:4247-53. [PMID: 10435637 DOI: 10.1038/sj.onc.1202789] [Citation(s) in RCA: 135] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
To assess the role of the p53 tumor suppressor gene in skin carcinogenesis by UV radiation, mice constitutively lacking one or both copies of the functional p53 gene were compared to wild-type mice for their susceptibility to UV carcinogenesis. Heterozygous mice showed greatly increased susceptibility to skin cancer induction, and homozygous p53 knockout mice were even more susceptible. Accelerated tumor development in the heterozygotes was not associated with loss of the remaining wild-type allele of p53, as reported for tumors induced by other carcinogens, but in many cases was associated with UV-induced mutations in p53. Tumors arose on the ears and dorsal skin of mice of all three genotypes, and homozygous knockout mice also developed ocular tumors, mainly melanomas. Skin tumors in the p53 knockout mice were predominately squamous cell carcinomas and were associated with premalignant lesions resembling actinic keratoses, whereas those in the heterozygous and wild-type mice were mainly sarcomas. These results demonstrate the importance of p53 in protecting against UV-induced cancers, particularly in the eye and epidermis.
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MESH Headings
- Animals
- Carcinoma, Squamous Cell/etiology
- Carcinoma, Squamous Cell/genetics
- Carcinoma, Squamous Cell/prevention & control
- Codon/genetics
- Crosses, Genetic
- DNA, Neoplasm/genetics
- Epidermis/metabolism
- Epidermis/radiation effects
- Exons/genetics
- Eye Neoplasms/etiology
- Eye Neoplasms/genetics
- Eye Neoplasms/prevention & control
- Gene Dosage
- Genes, p53
- Genetic Predisposition to Disease
- Genotype
- Keratosis/etiology
- Keratosis/genetics
- Melanoma, Experimental/etiology
- Melanoma, Experimental/genetics
- Melanoma, Experimental/prevention & control
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Mice, Transgenic
- Neoplasms, Radiation-Induced/genetics
- Neoplasms, Radiation-Induced/prevention & control
- Point Mutation
- Polymerase Chain Reaction
- Polymorphism, Single-Stranded Conformational
- Precancerous Conditions/etiology
- Precancerous Conditions/genetics
- Radiation Tolerance/genetics
- Sarcoma, Experimental/etiology
- Sarcoma, Experimental/genetics
- Sarcoma, Experimental/prevention & control
- Skin Neoplasms/etiology
- Skin Neoplasms/genetics
- Skin Neoplasms/prevention & control
- Specific Pathogen-Free Organisms
- Tumor Suppressor Protein p53/deficiency
- Tumor Suppressor Protein p53/physiology
- Ultraviolet Rays/adverse effects
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Affiliation(s)
- W Jiang
- Department of Immunology, The University of Texas M.D. Anderson Cancer Center, Houston 77030, USA
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41
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Friedberg EC, Meira LB. Database of mouse strains carrying targeted mutations in genes affecting cellular responses to DNA damage: version 3. Mutat Res 1999; 433:69-87. [PMID: 10102034 DOI: 10.1016/s0921-8777(98)00068-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Affiliation(s)
- E C Friedberg
- Department of Pathology, University of Texas Southwestern Medical Center, Dallas 75235, USA.
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42
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de Boer J, Hoeijmakers JH. Cancer from the outside, aging from the inside: mouse models to study the consequences of defective nucleotide excision repair. Biochimie 1999; 81:127-37. [PMID: 10214917 DOI: 10.1016/s0300-9084(99)80045-5] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
In recent years, mouse models have been generated to study the syndromes associated with a defect in nucleotide excision repair (NER). Thus, via conventional knockout gene targeting or by mimicking patient-specific alleles, mouse models for xeroderma pigmentosum (XP), Cockayne syndrome (CS) and photosensitive trichothiodystrophy (TTD) have been obtained. The generation of this series of mouse mutants allows in vivo investigation of some intriguing questions that have puzzled the field, such as the paradoxical absence of cancer development in TTD and CS despite their NER deficiencies, and the role of the ERCC1 gene in mitotic recombination and cross-link repair. Other interesting issues include the pathophysiology of the non-NER related clinical symptoms in TTD and CS patients and the proposed involvement of NER and transcription in the process of aging. This review will focus on data obtained thus far and discuss further utilization of the mouse mutants for unraveling some of the fascinating and medically relevant aspects associated with defects in NER and related processes.
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Affiliation(s)
- J de Boer
- MGC-Department of Cell Biology and Genetics, Rotterdam, The Netherlands
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43
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Friedberg EC, Meira LB, Cheo DL. Database of mouse strains carrying targeted mutations in genes affecting cellular responses to DNA damage. Version 2. Mutat Res 1998; 407:217-26. [PMID: 9653448 DOI: 10.1016/s0921-8777(97)00066-9] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- E C Friedberg
- Department of Pathology, University of Texas Southwestern Medical Center, Dallas 75235, USA.
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44
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Affiliation(s)
- M R Mowat
- Manitoba Institute of Cell Biology, Winnipeg, Canada
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45
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Frijhoff AF, Krul CA, de Vries A, Kelders MC, Weeda G, van Steeg H, Baan RA. Influence of nucleotide excision repair on N-hydroxy-2-acetylaminofluorene-induced mutagenesis studied in lambda lacZ-transgenic mice. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 1998; 31:41-47. [PMID: 9464314 DOI: 10.1002/(sici)1098-2280(1998)31:1<41::aid-em6>3.0.co;2-e] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
To study the influence of nucleotide excision repair (NER) on mutagenesis in vivo, ERCC1 +/-, XPA-/-, and wild-type (ERCC1+/+ and XPA+/+, respectively) lambda lacZ-transgenic mice were treated i.p. with N-hydroxy-2-acetylaminofluorene (N-OH-AAF) and lacZ mutant frequencies were determined in liver. No significant effect of the treatment on the mutant frequency in wild-type or ERCC1-heterozygous mice was observed. The liver mutant frequency appeared to be significantly increased in treated XPA-/- mice only. To distinguish N-OH-AAF-induced from spontaneous mutations, lacZ mutants derived from treated XPA-/- mice were subjected to DNA-sequence analysis and the spectrum obtained was compared to that established for lacZ mutants in liver of PBS-treated lambda lacZ-transgenic mice of the parent strain 40.6. The N-OH-AAF-induced mutation spectrum appeared to be significantly different from the spontaneous mutation spectrum: the former consisted of mainly (19/22) single bp substitutions targeted at G, of which the majority (12/19) were G:C-->T:A transversions, suggesting that N-(deoxyguanosin-8-yl)-2-aminofluorene [dG-C8-AF], the major DNA adduct in N-OH-AAF-treated mice, is the premutagenic lesion. After analysis of 21 spontaneous mutants, only ten single bp substitutions targeted at G were found, of which five were G:C-->T:A transversions. This study with XPA-/- lambda lacZ-transgenic mice shows that one of the components of NER, that is, the XPA protein, suppresses mutagenesis in vivo.
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Affiliation(s)
- A F Frijhoff
- Department of Molecular Toxicology, TNO Nutrition and Food Research Institute, Zeist, The Netherlands
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Cleaver JE, States JC. The DNA damage-recognition problem in human and other eukaryotic cells: the XPA damage binding protein. Biochem J 1997; 328 ( Pt 1):1-12. [PMID: 9359827 PMCID: PMC1218880 DOI: 10.1042/bj3280001] [Citation(s) in RCA: 76] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The capacity of human and other eukaryotic cells to recognize a disparate variety of damaged sites in DNA, and selectively excise and repair them, resides in a deceptively small simple protein, a 38-42 kDa zinc-finger binding protein, XPA (xeroderma pigmentosum group A), that has no inherent catalytic properties. One key to its damage-recognition ability resides in a DNA-binding domain which combines a zinc finger and a single-strand binding region which may infiltrate small single-stranded regions caused by helix-destabilizing lesions. Another is the augmentation of its binding capacity by interactions with other single-stranded binding proteins and helicases which co-operate in the binding and are unloaded at the binding site to facilitate further unwinding of the DNA and subsequent catalysis. The properties of these reactions suggest there must be considerable conformational changes in XPA and associated proteins to provide a flexible fit to a wide variety of damaged structures in the DNA.
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Affiliation(s)
- J E Cleaver
- Laboratory of Radiobiology and Environmental Health, University of California, San Francisco 94143-0750, USA
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Abstract
Transgenic and knockout mice have been proposed as substitutes for one of the standard 2-yr rodent assays. The advantages of using genetically engineered mouse models is that fewer mice are needed, the time to develop disease is greatly reduced, and the mice are predisposed to developing cancer by virtue of gain or loss of functions. The models currently being used have yielded a large amount of data and have proved to be informative for risk assessment; however, they are still far from ideal. In fact, they inherently do not reflect the complexity of mutation and carcinogenesis in humans. Recent advances in technology and the creation of new knockout mice may produce more useful and more sensitive models. This review covers two recent advances in technology--inducible and regulatable gene expression and targeted genetic modifications in the genome--that will allow us to make better models. I also discuss new gene deletion and transgenic mouse models and their potential impact on risk-assessment assays. These models are presented in the context of four basic components or events that occur in the multistep process leading to cancer: maintenance of gene expression patterns, genome stability and DNA repair, cell-cell communication and signaling, and cell-cycle regulation. Finally, surrogate markers and utility in risk assessment are also discussed. This review is meant to stimulate further discussion in the field and to generate excitement about working toward the next generation of risk-assessment models.
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Affiliation(s)
- M P Rosenberg
- Department of Genomics, Glaxo Wellcome Research, Inc., Research Triangle Park, North Carolina
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Meira LB, Cheo DL, Hammer RE, Burns DK, Reis A, Friedberg EC. Genetic interaction between HAP1/REF-1 and p53. Nat Genet 1997; 17:145. [PMID: 9326930 DOI: 10.1038/ng1097-145] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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Weeda G, Donker I, de Wit J, Morreau H, Janssens R, Vissers CJ, Nigg A, van Steeg H, Bootsma D, Hoeijmakers JH. Disruption of mouse ERCC1 results in a novel repair syndrome with growth failure, nuclear abnormalities and senescence. Curr Biol 1997; 7:427-39. [PMID: 9197240 DOI: 10.1016/s0960-9822(06)00190-4] [Citation(s) in RCA: 283] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND The structure-specific ERCC1/XPF endonuclease complex that contains the ERCC1 and XPF subunits is implicated in the repair of two distinct types of lesions in DNA: nucleotide excision repair (NER) for ultraviolet-induced lesions and bulky chemical adducts; and recombination repair of the very genotoxic interstrand cross-links. RESULTS Here, we present a detailed analysis of two types of mice with mutations in ERCC1, one in which the gene is 'knocked out', and one in which the encoded protein contains a seven amino-acid carboxy-terminal truncation. In addition to the previously reported symptoms of severe runting, abnormalities of liver nuclei and greatly reduced lifespan (which appeared less severe in the truncation mutant), both types of ERCC1-mutant mouse exhibited an absence of subcutaneous fat, early onset of ferritin deposition in the spleen, kidney malfunction, gross abnormalities of ploidy and cytoplasmic invaginations in nuclei of liver and kidney, and compromised NER and cross-link repair. We also found that heterozygosity for ERCC1 mutations did not appear to provide a selective advantage for chemically induced tumorigenesis. An important clue to the cause of the very severe ERCC1-mutant phenotypes is our finding that ERCC1-mutant cells undergo premature replicative senescence, unlike cells from mice with a defect only in NER. CONCLUSIONS Our results strongly suggest that the accumulation in ERCC1-mutant mice of endogenously generated DNA interstrand cross-links, which are normally repaired by ERCC1-dependent recombination repair, underlies both the early onset of cell cycle arrest and polyploidy in the liver and kidney. Thus, our work provides an insight into the molecular basis of ageing and highlights the role of ERCC1 and interstrand DNA cross-links.
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Affiliation(s)
- G Weeda
- Department of Cell Biology and Genetics, Medical Genetics Center, Erasmus University, Rotterdam P.O. Box 1738, 3000 DR, Rotterdam, The Netherlands
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Shen HM, Cheo DL, Friedberg E, Storb U. The inactivation of the XP-C gene does not affect somatic hypermutation or class switch recombination of immunoglobulin genes. Mol Immunol 1997; 34:527-33. [PMID: 9364218 DOI: 10.1016/s0161-5890(97)00064-3] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The mechanism of somatic hypermutation of immunoglobulin genes is not known, but appears to be linked to transcription and perhaps DNA repair. In order to determine if global DNA repair or the repair of the nontranscribed DNA strand is required for somatic mutation, we have analysed mice whose XP-C gene was inactivated by homologous recombination. Our study shows that hypermutation occurs in XP-C knockout mice with a normal frequency, suggesting that the XP-C gene product is not required for somatic hypermutation. Furthermore, we found that Ig gene switch recombination also is normal in these mice.
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Affiliation(s)
- H M Shen
- Department of Molecular Genetics and Cell Biology, University of Chicago, IL 60637, USA
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