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Sarker AH, Trego KS, Zhang W, Jacob P, Snijders A, Mao JH, Schick SF, Cooper PK, Hang B. Thirdhand smoke exposure causes replication stress and impaired transcription in human lung cells. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2020; 61:635-646. [PMID: 32267018 PMCID: PMC7363442 DOI: 10.1002/em.22372] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Revised: 02/29/2020] [Accepted: 03/27/2020] [Indexed: 05/12/2023]
Abstract
Thirdhand cigarette smoke (THS) is a newly described toxin that lingers in the indoor environment long after cigarettes have been extinguished. Emerging results from both cellular and animal model studies suggest that THS is a potential human health hazard. DNA damage derived from THS exposure could have genotoxic consequences that would lead to the development of diseases. However, THS exposure-induced interference with fundamental DNA transactions such as replication and transcription, and the role of DNA repair in ameliorating such effects, remain unexplored. Here, we found that THS exposure increased the percentage of cells in S-phase, suggesting impaired S-phase progression. Key DNA damage response proteins including RPA, ATR, ATM, CHK1, and BRCA1 were activated in lung cells exposed to THS, consistent with replication stress. In addition, THS exposure caused increased 53BP1 foci, indicating DNA double-strand break induction. Consistent with these results, we observed increased micronuclei formation, a marker of genomic instability, in THS-exposed cells. Exposure to THS also caused a significant increase in phosphorylated RNA Polymerase II engaged in transcription elongation, suggesting an increase in transcription-blocking lesions. In agreement with this conclusion, ongoing RNA synthesis was very significantly reduced by THS exposure. Loss of nucleotide excision repair exacerbated the reduction in RNA synthesis, suggesting that bulky DNA adducts formed by THS are blocks to transcription. The adverse impact on both replication and transcription supports genotoxic stress as a result of THS exposure, with important implications for both cancer and other diseases.
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Affiliation(s)
- Altaf H. Sarker
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
- Correspondence: Dr. Altaf H. Sarker, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720, USA, Tel: (510) 486-6113,
| | - Kelly S. Trego
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Weiguo Zhang
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Peyton Jacob
- Department of Medicine, Division of Cardiology, Clinical Pharmacology Program, University of California, San Francisco, CA 94143, USA
| | - Antoine Snijders
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Jian-Hua Mao
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Suzaynn F. Schick
- Department of Medicine, Division of Occupational and Environmental Medicine, University of California, San Francisco, CA 94143, USA
| | - Priscilla K. Cooper
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Bo Hang
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
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Banda DM, Nuñez NN, Burnside MA, Bradshaw KM, David SS. Repair of 8-oxoG:A mismatches by the MUTYH glycosylase: Mechanism, metals and medicine. Free Radic Biol Med 2017; 107:202-215. [PMID: 28087410 PMCID: PMC5457711 DOI: 10.1016/j.freeradbiomed.2017.01.008] [Citation(s) in RCA: 66] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/17/2016] [Revised: 01/01/2017] [Accepted: 01/04/2017] [Indexed: 12/12/2022]
Abstract
Reactive oxygen and nitrogen species (RONS) may infringe on the passing of pristine genetic information by inducing DNA inter- and intra-strand crosslinks, protein-DNA crosslinks, and chemical alterations to the sugar or base moieties of DNA. 8-Oxo-7,8-dihydroguanine (8-oxoG) is one of the most prevalent DNA lesions formed by RONS and is repaired through the base excision repair (BER) pathway involving the DNA repair glycosylases OGG1 and MUTYH in eukaryotes. MUTYH removes adenine (A) from 8-oxoG:A mispairs, thus mitigating the potential of G:C to T:A transversion mutations from occurring in the genome. The paramount role of MUTYH in guarding the genome is well established in the etiology of a colorectal cancer predisposition syndrome involving variants of MUTYH, referred to as MUTYH-associated polyposis (MAP). In this review, we highlight recent advances in understanding how MUTYH structure and related function participate in the manifestation of human disease such as MAP. Here we focus on the importance of MUTYH's metal cofactor sites, including a recently discovered "Zinc linchpin" motif, as well as updates to the catalytic mechanism. Finally, we touch on the insight gleaned from studies with MAP-associated MUTYH variants and recent advances in understanding the multifaceted roles of MUTYH in the cell, both in the prevention of mutagenesis and tumorigenesis.
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Affiliation(s)
- Douglas M Banda
- Department of Chemistry, University of California, Davis, One Shields Avenue, Davis, CA 95616, United States
| | - Nicole N Nuñez
- Department of Chemistry, University of California, Davis, One Shields Avenue, Davis, CA 95616, United States
| | - Michael A Burnside
- Department of Chemistry, University of California, Davis, One Shields Avenue, Davis, CA 95616, United States
| | - Katie M Bradshaw
- Department of Chemistry, University of California, Davis, One Shields Avenue, Davis, CA 95616, United States
| | - Sheila S David
- Department of Chemistry, University of California, Davis, One Shields Avenue, Davis, CA 95616, United States.
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3
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Medda E, Minoprio A, Nisticò L, Bocca B, Simonelli V, D'Errico M, Calcagnile A, Giuliani A, Toccaceli V, Minghetti L, Alimonti A, Stazi MA, Mazzei F, Dogliotti E. The response to oxidative stress and metallomics analysis in a twin study: The role of the environment. Free Radic Biol Med 2016; 97:236-243. [PMID: 27264237 DOI: 10.1016/j.freeradbiomed.2016.05.026] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/09/2015] [Revised: 05/23/2016] [Accepted: 05/29/2016] [Indexed: 02/02/2023]
Abstract
Inefficient response to oxidative stress has been associated with ageing and health risk. Metals are known to inhibit DNA repair and may modify the antioxidant response. How genetic variability and lifestyle factors modulate the response to oxidative stress is poorly explored. Our study aims to disentangle the contribution of genetics and environmental exposures to oxidative stress response using data from twin pairs. The non-enzymatic antioxidant capacity (NEAC), the repair capacity of 8-oxo-7,8-dihydroguanine (OGG activity) and the levels of 12 metals were measured in blood of 64 monozygotic and 31 dizygotic twin pairs. The contributions of genetic and environmental effects were assessed using standard univariate twin modelling. NEAC and OGG activity significantly decreased with age. Gender-, age- and body mass index-associated differences were identified for some metals. Principal Component Analysis identified two groups of metals whose levels in blood were highly correlated: As, Hg, Pb, Se, Zn and Al, Co, Cr, Mn, Ni. The environmental influence was predominant on OGG activity and NEAC variance whereas for most metals the best-fitting model incorporated additive genetic and unique environmental sources of variance. NEAC and OGG activity were both inversely correlated with blood levels of various metals. The inhibition of OGG activity by Cd was largely explained by smoking. Our data show a substantial role of environmental factors in NEAC and OGG activity variance that is not explained by twins' age. Exogenous environmental factors such as metals contribute to oxidative stress by decreasing NEAC and inhibiting repair of oxidatively-induced DNA damage.
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Affiliation(s)
- Emanuela Medda
- National Center of Epidemiology, Surveillance and Health Promotion, Istituto Superiore di Sanità, Rome, Italy
| | - Anna Minoprio
- Department of Environment and Primary Prevention, Istituto Superiore di Sanità, Rome, Italy
| | - Lorenza Nisticò
- National Center of Epidemiology, Surveillance and Health Promotion, Istituto Superiore di Sanità, Rome, Italy
| | - Beatrice Bocca
- Department of Environment and Primary Prevention, Istituto Superiore di Sanità, Rome, Italy
| | - Valeria Simonelli
- Department of Environment and Primary Prevention, Istituto Superiore di Sanità, Rome, Italy
| | - Mariarosaria D'Errico
- Department of Environment and Primary Prevention, Istituto Superiore di Sanità, Rome, Italy
| | - Angelo Calcagnile
- Department of Environment and Primary Prevention, Istituto Superiore di Sanità, Rome, Italy
| | - Alessandro Giuliani
- Department of Environment and Primary Prevention, Istituto Superiore di Sanità, Rome, Italy
| | - Virgilia Toccaceli
- National Center of Epidemiology, Surveillance and Health Promotion, Istituto Superiore di Sanità, Rome, Italy
| | - Luisa Minghetti
- Department of Cell Biology and Neuroscience, Istituto Superiore di Sanità, Rome, Italy
| | - Alessandro Alimonti
- Department of Environment and Primary Prevention, Istituto Superiore di Sanità, Rome, Italy
| | - Maria Antonietta Stazi
- National Center of Epidemiology, Surveillance and Health Promotion, Istituto Superiore di Sanità, Rome, Italy
| | - Filomena Mazzei
- Department of Environment and Primary Prevention, Istituto Superiore di Sanità, Rome, Italy.
| | - Eugenia Dogliotti
- Department of Environment and Primary Prevention, Istituto Superiore di Sanità, Rome, Italy.
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Ferreira TS, Lanzetti M, Barroso MV, Rueff-Barroso CR, Benjamim CF, de Brito-Gitirana L, Porto LC, Valença SS. Oxidative stress and inflammation are differentially affected by atorvastatin, pravastatin, rosuvastatin, and simvastatin on lungs from mice exposed to cigarette smoke. Inflammation 2015; 37:1355-65. [PMID: 24609836 DOI: 10.1007/s10753-014-9860-y] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Our aim was to investigate the effects of four different statins on acute lung inflammation induced by cigarette smoke (CS). C57BL/6 male mice were divided into a control group (sham-smoked) and mice exposed to CS from 12 cigarettes/day for 5 days. Mice exposed to CS were grouped and treated with vehicle (i.p.), atorvastatin (10 mg/kg), pravastatin (10 mg/kg), rosuvastatin (5 mg/kg), or simvastatin (20 mg/kg). Treatment with statins differentially improved the pulmonary response when compared to the CS group. Atorvastatin and pravastatin demonstrated slightly effects on inflammation and oxidative stress. Rosuvastatin demonstrated the best anti-inflammatory effect, whereas simvastatin demonstrated the best antioxidant response.
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Affiliation(s)
- Thiago Santos Ferreira
- Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
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Cho HY, Jedlicka AE, Gladwell W, Marzec J, McCaw ZR, Bienstock RJ, Kleeberger SR. Association of Nrf2 polymorphism haplotypes with acute lung injury phenotypes in inbred strains of mice. Antioxid Redox Signal 2015; 22:325-38. [PMID: 25268541 PMCID: PMC4298158 DOI: 10.1089/ars.2014.5942] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
AIMS Nrf2 is a master transcription factor for antioxidant response element (ARE)-mediated cytoprotective gene induction. A protective role for pulmonary Nrf2 was determined in model oxidative disorders, including hyperoxia-induced acute lung injury (ALI). To obtain additional insights into the function and genetic regulation of Nrf2, we assessed functional single nucleotide polymorphisms (SNPs) of Nrf2 in inbred mouse strains and tested whether sequence variation is associated with hyperoxia susceptibility. RESULTS Nrf2 SNPs were compiled from publicly available databases and by re-sequencing DNA from inbred strains. Hierarchical clustering of Nrf2 SNPs categorized the strains into three major haplotypes. Hyperoxia susceptibility was greater in haplotypes 2 and 3 strains than in haplotype 1 strains. A promoter SNP -103 T/C adding an Sp1 binding site in haplotype 2 diminished promoter activation basally and under hyperoxia. Haplotype 3 mice bearing nonsynonymous coding SNPs located in (1862 A/T, His543Gln) and adjacent to (1417 T/C, Thr395Ile) the Neh1 domain showed suppressed nuclear transactivation of pulmonary Nrf2 relative to other strains, and overexpression of haplotype 3 Nrf2 showed lower ARE responsiveness than overexpression of haplotype 1 Nrf2 in airway cells. Importantly, we found a significant correlation of Nrf2 haplotypes and hyperoxic lung injury phenotypes. INNOVATION AND CONCLUSION The results indicate significant influence of Nrf2 polymorphisms and haplotypes on gene function and hyperoxia susceptibility. Our findings further support Nrf2 as a genetic determinant in ALI pathogenesis and provide useful tools for investigators who use mouse strains classified by Nrf2 haplotypes to elucidate the role for Nrf2 in oxidative disorders.
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Affiliation(s)
- Hye-Youn Cho
- 1 Laboratory of Respiratory Biology, National Institute of Environmental Health Sciences, National Institutes of Health , Research Triangle Park, North Carolina
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Fikrova P, Stetina R, Hrnciarik M, Hrnciarikova D, Hronek M, Zadak Z. DNA crosslinks, DNA damage and repair in peripheral blood lymphocytes of non-small cell lung cancer patients treated with platinum derivatives. Oncol Rep 2013; 31:391-6. [PMID: 24154806 DOI: 10.3892/or.2013.2805] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2013] [Accepted: 09/03/2013] [Indexed: 11/06/2022] Open
Abstract
Lung cancer is the leading cause of cancer-related mortality in the world. Chemotherapy has been the mainstay of treatment for advanced non-small cell lung cancer (NSCLC) and platinum-based derivatives have been shown to improve overall survival. The aim of the present study was to investigate the DNA damage [single strand breaks (SSBs) and DNA crosslinks] and DNA repair in peripheral blood lymphocytes in patients with NSCLC treated with platinum derivatives using modified comet assay. Twenty patients in the final (4th) stage of NSCLC and 10 age-corresponding healthy controls participated in the study. Alkaline comet assay was performed according to the appropriate protocol. The DNA base excision repair (BER) activity of the controls was significantly higher compared to that of cancer patients, and the activity of DNA nucleotide excision repair (NER) was almost at the same level both in controls and patients. We observed changes in the amount of SSBs and DNA crosslinks during the course of chemotherapy. We found a significantly higher level of SSBs immediately after administration of chemotherapy. Similarly, we found the highest incidence of DNA crosslinks immediately or 1 day after chemotherapy (compared to measurement before chemotherapy). Moreover, we compared the levels of DNA repair in patients who survived chemotherapy with those in patients who died in the course of chemotherapy: the activity of BER was higher in the case of surviving patients, while the levels of NER were essentially the same. The data arising from the present study confirm the findings of other studies dealing with DNA damage and repair in cancer patients treated with chemotherapy. Moreover, our results indicated that despite the fact that cisplatin-DNA adducts are removed by the NER pathway, BER may also play a role in the clinical status of patients and their survival.
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Affiliation(s)
- Petra Fikrova
- Department of Biological and Medical sciences, Faculty of Pharmacy, Charles University in Prague, Hradec Králové, Czech Republic
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Simonelli V, Mazzei F, D'Errico M, Dogliotti E. Reprint of: gene susceptibility to oxidative damage: from single nucleotide polymorphisms to function. Mutat Res 2012; 736:104-16. [PMID: 22732424 DOI: 10.1016/j.mrfmmm.2012.06.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2011] [Revised: 09/27/2011] [Accepted: 10/27/2011] [Indexed: 11/18/2022]
Abstract
Oxidative damage to DNA can cause mutations, and mutations can lead to cancer. DNA repair of oxidative damage should therefore play a pivotal role in defending humans against cancer. This is exemplified by the increased risk of colorectal cancer of patients with germ-line mutations of the oxidative damage DNA glycosylase MUTYH. In contrast to germ-line mutations in DNA repair genes, which cause a strong deficiency in DNA repair activity in all cell types, the role of single nucleotide polymorphisms (SNPs) in sporadic cancer is unclear also because deficiencies in DNA repair, if any, are expected to be much milder. Further slowing down progress are the paucity of accurate and reproducible functional assays and poor epidemiological design of many studies. This review will focus on the most common and widely studied SNPs of oxidative DNA damage repair proteins trying to bridge the information available on biochemical and structural features of the repair proteins with the functional effects of these variants and their potential impact on the pathogenesis of disease.
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Affiliation(s)
- Valeria Simonelli
- Department of Environment and Primary Prevention, Istituto Superiore di Sanità, Rome, Italy.
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8
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Simonelli V, Mazzei F, D'Errico M, Dogliotti E. Gene susceptibility to oxidative damage: from single nucleotide polymorphisms to function. Mutat Res 2012; 731:1-13. [PMID: 22155132 DOI: 10.1016/j.mrfmmm.2011.10.012] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2011] [Revised: 09/27/2011] [Accepted: 10/27/2011] [Indexed: 05/31/2023]
Abstract
Oxidative damage to DNA can cause mutations, and mutations can lead to cancer. DNA repair of oxidative damage should therefore play a pivotal role in defending humans against cancer. This is exemplified by the increased risk of colorectal cancer of patients with germ-line mutations of the oxidative damage DNA glycosylase MUTYH. In contrast to germ-line mutations in DNA repair genes, which cause a strong deficiency in DNA repair activity in all cell types, the role of single nucleotide polymorphisms (SNPs) in sporadic cancer is unclear also because deficiencies in DNA repair, if any, are expected to be much milder. Further slowing down progress are the paucity of accurate and reproducible functional assays and poor epidemiological design of many studies. This review will focus on the most common and widely studied SNPs of oxidative DNA damage repair proteins trying to bridge the information available on biochemical and structural features of the repair proteins with the functional effects of these variants and their potential impact on the pathogenesis of disease.
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Affiliation(s)
- Valeria Simonelli
- Department of Environment and Primary Prevention, Istituto Superiore di Sanità, Rome, Italy.
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9
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Reduced expression of DNA repair genes (XRCC1, XPD, and OGG1) in squamous cell carcinoma of head and neck in North India. Tumour Biol 2011; 33:111-9. [PMID: 22081374 DOI: 10.1007/s13277-011-0253-7] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2011] [Accepted: 10/18/2011] [Indexed: 12/13/2022] Open
Abstract
Squamous cell carcinoma of head and neck (SCCHN) is the sixth most common cancer globally, and in India, it accounts for 30% of all cancer cases. Epidemiological studies have shown a positive association between defective DNA repair capacity and SCCHN. The underlying mechanism of their involvement is not well understood. In the present study, we have analyzed the relationship between SCCHN and the expression of DNA repair genes namely X-ray repair cross-complementing group 1 (XRCC1), xeroderma pigmentosum group D (XPD), and 8-oxoguanine DNA glycosylase (OGG1) in 75 SCCHN cases and equal number of matched healthy controls. Additionally, levels of DNA adduct [8-hydroxyguanine (8-OHdG)] in 45 SCCHN cases and 45 healthy controls were also determined, to ascertain a link between mRNA expression of these three genes and DNA adducts. The relative expression of XRCC1, XPD, and OGG1 in head and neck cancer patients was found to be significantly low as compared to controls. The percent difference of mean relative expression between cases and controls demonstrated maximum lowering in OGG1 (47.3%) > XPD (30.7%) > XRCC1 (25.2%). A negative Spearmen correlation between XRCC1 vs. 8-OHdG in cases was observed. In multivariate logistic regression analysis (adjusting for age, gender, smoking status, and alcohol use), low expression of XRCC1, XPD, and OGG1 was associated with a statistically significant increased risk of SCCHN [crude odds ratios (ORs) (95%CI) OR 2.10; (1.06-4.17), OR 2.76; (1.39-5.49), and 5.24 (2.38-11.52), respectively]. In conclusion, our study demonstrated that reduced expression of XRCC1, XPD, and OGG1 is associated with more than twofold increased risk in SCCHN.
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10
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Lillenes MS, Espeseth T, Støen M, Lundervold AJ, Frye SA, Rootwelt H, Reinvang I, Tønjum T. DNA base excision repair gene polymorphisms modulate human cognitive performance and decline during normal life span. Mech Ageing Dev 2011; 132:449-58. [DOI: 10.1016/j.mad.2011.08.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2010] [Revised: 06/25/2011] [Accepted: 08/14/2011] [Indexed: 10/17/2022]
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Li SY, Zhang XY, Zhang X, Lan Y, Hua ZC. A convenient fluorescent-labeled assay for in vitro measurement of DNA mismatch repair activity. BIOMEDICAL AND ENVIRONMENTAL SCIENCES : BES 2010; 23:496-501. [PMID: 21315249 DOI: 10.1016/s0895-3988(11)60013-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2010] [Accepted: 09/17/2010] [Indexed: 05/30/2023]
Abstract
OBJECTIVE The assay of DNA mismatch repair (MMR) activity can be used as a biomarker for environmental condition detection and human disease diagnosis. Radioactive ³²P-endlabeled DNA containing mismatch is extensively used as the substrate for MMR activity analyses. The aim of the present study is to develop a simple non-radioactive, but equally specific and sensitive method for the MMR activity assay. METHODS A fluorescent label was chosen to replace the radioactive isotope label. Sensitive evaluation of the fluorescent label was carried out for the first time, and then the fluorescent label was compared with the isotope label in the MMR activity and DNA binding assays. RESULT LOD (limit of detection) of the fluorescent label was about 0.1 fmol and the relative signal strength displayed a pretty good linear relationship. Moreover, the fluorescent label method has equivalent sensitivity and performance as compared with the classical radioactive method in experiments. CONCLUSION In light of the sensitivity, reproducibility, safety, rapidity and long lifespan of the fluorescent label, this improved method can be applied to evaluation of biologic and toxic effects of environmental pollutants on man and other forms of life.
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Affiliation(s)
- Shi-Ying Li
- The State Key Laboratory of Pharmaceutical Biotechnology and Jiangsu Center of Hepatobiliary Diseases, School of Stomatology and Affiliated Stomatological Hospital, Nanjing University, Nanjing 210093, Jiangsu, China
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Decordier I, Loock KV, Kirsch-Volders M. Phenotyping for DNA repair capacity. MUTATION RESEARCH-REVIEWS IN MUTATION RESEARCH 2010; 705:107-129. [PMID: 20478396 DOI: 10.1016/j.mrrev.2010.05.002] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2009] [Revised: 05/10/2010] [Accepted: 05/10/2010] [Indexed: 12/21/2022]
Affiliation(s)
- Ilse Decordier
- Laboratorium voor Cellulaire Genetica, Vrije Universiteit Brussel, Belgium.
| | - Kim Vande Loock
- Laboratorium voor Cellulaire Genetica, Vrije Universiteit Brussel, Belgium
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13
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Rai P. Oxidation in the nucleotide pool, the DNA damage response and cellular senescence: Defective bricks build a defective house. Mutat Res 2010; 703:71-81. [PMID: 20673809 DOI: 10.1016/j.mrgentox.2010.07.010] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2010] [Accepted: 07/19/2010] [Indexed: 12/20/2022]
Abstract
Activation of persistent DNA damage response (DDR) signaling is associated with the induction of a permanent proliferative arrest known as cellular senescence, a phenomenon intrinsically linked to both tissue aging as well as tumor suppression. The DNA damage observed in senescent cells has been attributed to elevated levels of reactive oxygen species (ROS), failing DNA damage repair processes, and/or oncogenic activation. It is not clear how labile molecules such as ROS are able to damage chromatin-bound DNA to a sufficient extent to invoke persistent DNA damage and DDR signaling. Recent evidence suggests that the nucleotide pool is a significant target for oxidants and that oxidized nucleotides, once incorporated into genomic DNA, can lead to the induction of a DNA strand break-associated DDR that triggers senescence in normal cells and in cells sustaining oncogene activation. Evasion of this DDR and resulting senescence is a key step in tumor progression. This review will explore the role of oxidation in the nucleotide pool as a major effector of oxidative stress-induced genotoxic damage and DDR in the context of cellular senescence and tumorigenic transformation.
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Affiliation(s)
- Priyamvada Rai
- Division of Gerontology and Geriatric Medicine, Department of Medicine, Rosenstiel Medical Sciences Building, Rm#7094/Locator Code: D-503, 1600 NW 10th Ave, Miller School of Medicine, University of Miami, Miami, FL 33136, United States.
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14
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Cho HY, Gladwell W, Wang X, Chorley B, Bell D, Reddy SP, Kleeberger SR. Nrf2-regulated PPAR{gamma} expression is critical to protection against acute lung injury in mice. Am J Respir Crit Care Med 2010; 182:170-82. [PMID: 20224069 DOI: 10.1164/rccm.200907-1047oc] [Citation(s) in RCA: 149] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
RATIONALE The NF-E2 related factor 2 (Nrf2)-antioxidant response element (ARE) pathway is essential for protection against oxidative injury and inflammation including hyperoxia-induced acute lung injury. Microarray expression profiling revealed that lung peroxisome proliferator activated receptor gamma (PPARgamma) induction is suppressed in hyperoxia-susceptible Nrf2-deficient (Nrf2(-/-)) mice compared with wild-type (Nrf2(+/+)) mice. PPARgamma has pleiotropic beneficial effects including antiinflammation in multiple tissues. OBJECTIVES We tested the hypothesis that PPARgamma is an important determinant of pulmonary responsivity to hyperoxia regulated by Nrf2. METHODS A computational bioinformatic method was applied to screen potential AREs in the Pparg promoter for Nrf2 binding. The functional role of a potential ARE was investigated by in vitro promoter analysis. A role for PPARgamma in hyperoxia-induced acute lung injury was determined by temporal silencing of PPARgamma via intranasal delivery of PPARgamma-specific interference RNA and by administration of a PPARgamma ligand 15-deoxy-Delta(12,14)-prostaglandin J(2) in mice. MEASUREMENTS AND MAIN RESULTS Deletion or site-directed mutagenesis of a potential ARE spanning -784/-764 sequence significantly attenuated hyperoxia-increased Pparg promoter activity in airway epithelial cells overexpressing Nrf2, indicating that the -784/-764 ARE is critical for Nrf2-regulated PPARgamma expression. Mice with decreased lung PPARgamma by specific interference RNA treatment had significantly augmented hyperoxia-induced pulmonary inflammation and injury. 15 Deoxy-Delta(12,14)-prostaglandin J(2) administration significantly reduced hyperoxia-induced lung inflammation and edema in Nrf2(+/+), but not in Nrf2(-/-) mice. CONCLUSIONS Results indicate for the first time that Nrf2-driven PPARgamma induction has an essential protective role in pulmonary oxidant injury. Our observations provide new insights into the therapeutic potential of PPARgamma in airway oxidative inflammatory disorders.
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Affiliation(s)
- Hye-Youn Cho
- Laboratory of Respiratory Biology, National Institute of Environmental Health Sciences, National Institutes of Health, 111 TW Alexander Dr., Building 101, MD D-201, Research Triangle Park, NC 27709, USA.
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15
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Hamann I, Schwerdtle T, Hartwig A. Establishment of a non-radioactive cleavage assay to assess the DNA repair capacity towards oxidatively damaged DNA in subcellular and cellular systems and the impact of copper. Mutat Res 2009; 669:122-130. [PMID: 19505484 DOI: 10.1016/j.mrfmmm.2009.05.011] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2009] [Revised: 05/19/2009] [Accepted: 05/27/2009] [Indexed: 05/27/2023]
Abstract
Oxidative stress is involved in many diseases, and the search for appropriate biomarkers is one major focus in molecular epidemiology. 8-Oxoguanine (8-oxoG), a potentially mutagenic DNA lesion, is considered to be a sensitive biomarker for oxidative stress. Another approach consists in assessing the repair capacity towards 8-oxoG, mediated predominantly by the human 8-oxoguanine DNA glycosylase 1 (hOGG1). With respect to the latter, during the last few years so-called cleavage assays have been described, investigating the incision of (32)P-labelled and 8-oxoG damaged oligonucleotides by cell extracts. Within the present study, a sensitive non-radioactive test system based on a Cy5-labelled oligonucleotide has been established. Sources of incision activity are isolated proteins or extracts prepared from cultured cells and peripheral blood mononuclear cells (PBMC). After comparing different oligonucleotide structures, a hairpin-like structure was selected which was not degraded by cell extracts. Applying this test system the impact of copper on the activity of isolated hOGG1 and on hOGG activity in A549 cells was examined, showing a distinct inhibition of the isolated protein at low copper concentration as compared to a modest inhibition of hOGG activity in cells at beginning cytotoxic concentrations. For investigating PBMC, all reaction conditions, including the amounts of oligonucleotide and cell extract as well as the reaction time have been optimized. The incision activities of PBMC protein extracts obtained from different donors have been investigated, and inter-individual differences have been observed. In summary, the established method is as sensitive and even faster than the radioactive technique, and additionally, offers the advantage of reduced costs and low health risk.
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Affiliation(s)
- Ingrit Hamann
- Fachgebiet Lebensmittelchemie und Toxikologie, Institut für Lebensmitteltechnologie und Lebensmittelchemie, Technische Universität Berlin, Berlin, Germany
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16
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The recombination protein RAD52 cooperates with the excision repair protein OGG1 for the repair of oxidative lesions in mammalian cells. Mol Cell Biol 2009; 29:4441-54. [PMID: 19506022 DOI: 10.1128/mcb.00265-09] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Oxidized bases are common types of DNA modifications. Their accumulation in the genome is linked to aging and degenerative diseases. These modifications are commonly repaired by the base excision repair (BER) pathway. Oxoguanine DNA glycosylase (OGG1) initiates BER of oxidized purine bases. A small number of protein interactions have been identified for OGG1, while very few appear to have functional consequences. We report here that OGG1 interacts with the recombination protein RAD52 in vitro and in vivo. This interaction has reciprocal functional consequences as OGG1 inhibits RAD52 catalytic activities and RAD52 stimulates OGG1 incision activity, likely increasing its turnover rate. RAD52 colocalizes with OGG1 after oxidative stress to cultured cells, but not after the direct induction of double-strand breaks by ionizing radiation. Human cells depleted of RAD52 via small interfering RNA knockdown, and mouse cells lacking the protein via gene knockout showed increased sensitivity to oxidative stress. Moreover, cells depleted of RAD52 show higher accumulation of oxidized bases in their genome than cells with normal levels of RAD52. Our results indicate that RAD52 cooperates with OGG1 to repair oxidative DNA damage and enhances the cellular resistance to oxidative stress. Our observations suggest a coordinated action between these proteins that may be relevant when oxidative lesions positioned close to strand breaks impose a hindrance to RAD52 catalytic activities.
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17
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Forsbring M, Vik ES, Dalhus B, Karlsen TH, Bergquist A, Schrumpf E, Bjørås M, Boberg KM, Alseth I. Catalytically impaired hMYH and NEIL1 mutant proteins identified in patients with primary sclerosing cholangitis and cholangiocarcinoma. Carcinogenesis 2009; 30:1147-54. [PMID: 19443904 PMCID: PMC2704287 DOI: 10.1093/carcin/bgp118] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The human hMYH and NEIL1 genes encode DNA glycosylases involved in repair of oxidative base damage and mutations in these genes are associated with certain cancers. Primary sclerosing cholangitis (PSC), a chronic cholestatic liver disease characterized by inflammatory destruction of the biliary tree, is often complicated by the development of cholangiocarcinoma (CCA). Here, we aimed to investigate the influence of genetic variations in the hMYH and NEIL1 genes on risk of CCA in PSC patients. The hMYH and NEIL1 gene loci in addition to the DNA repair genes hOGG1, NTHL1 and NUDT1 were analyzed in 66 PSC patients (37 with CCA and 29 without cancer) by complete genomic sequencing of exons and adjacent intronic regions. Several single-nucleotide polymorphisms and mutations were identified and severe impairment of protein function was observed for three non-synonymous variants. The NEIL1 G83D mutant was dysfunctional for the major oxidation products 7,8-dihydro-8-oxoguanine (8oxoG), thymine glycol and dihydrothymine in duplex DNA, and the ability to perform δ-elimination at abasic sites was significantly reduced. The hMYH R260Q mutant had severe defect in adenine DNA glycosylase activity, whereas hMYH H434D could excise adenines from A:8oxoG pairs but not from A:G mispairs. We found no overall associations between the 18 identified variants and susceptibility to CCA in PSC patients; however, the impaired variants may be of significance for carcinogenesis in general. Our findings demonstrate the importance of complete resequencing of selected candidate genes in order to identify rare genetic variants and their possible contribution to individual susceptibility to cancer development.
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Affiliation(s)
- Monika Forsbring
- Institute of Medical Microbiology, Rikshospitalet University Hospital HF and Centre for Molecular Biology and Neuroscience, University of Oslo, Oslo, Norway
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18
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Sin DD, Man SP, McWilliams A, Lam S. Surfactant Protein D and Bronchial Dysplasia in Smokers at High Risk of Lung Cancer. Chest 2008; 134:582-588. [DOI: 10.1378/chest.08-0600] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
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19
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Kennedy CH, Catallo WJ, Wilson VL, Mitchell JB. Combustion products of 1,3-butadiene inhibit catalase activity and induce expression of oxidative DNA damage repair enzymes in human bronchial epithelial cells. Cell Biol Toxicol 2008; 25:457-70. [PMID: 18685817 DOI: 10.1007/s10565-008-9100-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2008] [Accepted: 07/21/2008] [Indexed: 10/21/2022]
Abstract
1,3-Butadiene, an important petrochemical, is commonly burned off when excess amounts need to be destroyed. This combustion process produces butadiene soot (BDS), which is composed of a complex mixture of polycyclic aromatic hydrocarbons in particulates ranging in size from <1 microm to 1 mm. An organic extract of BDS is both cytotoxic and genotoxic to normal human bronchial epithelial (NHBE) cells. Based on the oxidizing potential of BDS, we hypothesized that an organic extract of this particulate matter would (1) cause enzyme inactivation due to protein amino acid oxidation and (2) induce oxidative DNA damage in NHBE cells. Thus, our aims were to determine the effect of butadiene soot ethanol extract (BSEE) on both enzyme activity and the expression of proteins involved in the repair of oxidative DNA damage. Catalase was found to be sensitive to BDS as catalase activity was potently diminished in the presence of BSEE. Using Western analysis, both the alpha isoform of human 8-oxoguanine DNA glycosylase (alpha-hOGG1) and human apurinic/apyrimidinic endonuclease (APE-1) were shown to be significantly overexpressed as compared to untreated controls after exposure of NHBE cells to BSEE. Our results indicate that BSEE is capable of effectively inactivating the antioxidant enzyme catalase, presumably via oxidation of protein amino acids. The presence of oxidized biomolecules may partially explain the extranuclear fluorescence that is detected when NHBE cells are treated with an organic extract of BDS. Overexpression of both alpha-hOGG1 and APE-1 proteins following treatment of NHBE cells with BSEE suggests that this mixture causes oxidative DNA damage.
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Affiliation(s)
- Christopher H Kennedy
- Department of Biochemistry, Lake Erie College of Osteopathic Medicine, Erie, PA 16509-1025, USA.
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20
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Paz-Elizur T, Sevilya Z, Leitner-Dagan Y, Elinger D, Roisman LC, Livneh Z. DNA repair of oxidative DNA damage in human carcinogenesis: potential application for cancer risk assessment and prevention. Cancer Lett 2008; 266:60-72. [PMID: 18374480 DOI: 10.1016/j.canlet.2008.02.032] [Citation(s) in RCA: 149] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2008] [Revised: 01/31/2008] [Accepted: 02/11/2008] [Indexed: 12/19/2022]
Abstract
Efficient DNA repair mechanisms comprise a critical component in the protection against human cancer, as indicated by the high predisposition to cancer of individuals with germ-line mutations in DNA repair genes. This includes biallelic germ-line mutations in the MUTYH gene, encoding a DNA glycosylase that is involved in the repair of oxidative DNA damage, which strongly predispose humans to a rare hereditary form of colorectal cancer. Extensive research efforts including biochemical, enzymological and genetic studies in model organisms established that the oxidative DNA lesion 8-oxoguanine is mutagenic, and that several DNA repair mechanisms operate to prevent its potentially mutagenic and carcinogenic outcome. Epidemiological studies on the association with sporadic cancers of single nucleotide polymorphisms in genes such as OGG1, involved in the repair of 8-oxoguanine yielded conflicting results, and suggest a minor effect at best. A new approach based on the functional analysis of DNA repair enzymatic activity showed that reduced activity of 8-oxoguanine DNA glycosylase (OGG) is a risk factor in lung and head and neck cancer. Moreover, the combination of smoking and low OGG activity was associated with a higher risk, suggesting a potential strategy for risk assessment and prevention of lung cancer, as well as other types of cancer.
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Affiliation(s)
- Tamar Paz-Elizur
- Department of Biological Chemistry, Weizmann Institute of Science, Rehovot 76100, Israel
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21
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Taniguchi Y, Kool ET. Nonpolar isosteres of damaged DNA bases: effective mimicry of mutagenic properties of 8-oxopurines. J Am Chem Soc 2007; 129:8836-44. [PMID: 17592846 DOI: 10.1021/ja071970q] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A substantial fraction of mutations that arise in the cell comes from oxidative damage to DNA bases. Oxidation of purine bases at the 8-position, yielding 8-oxo-G and 8-oxo-A, results in conformational changes (from anti to syn) that cause miscoding during DNA replication. Here we describe the synthesis and biophysical and biochemical properties of low-polarity shape mimics of 8-oxopurines, and we report that these new analogues exhibit remarkable mimicry of the mutagenic properties of the natural damaged bases. A 2-chloro-4-fluoroindole nucleoside (1) was designed as an isosteric analogue of 8-oxo-dG, and a 2-chloro-4-methylbenzimidazole nucleoside (2) as a mimic of 8-oxo-dA. The nucleosides were prepared by reaction of the parent heterocycles with Hoffer's chlorodeoxyribose derivative. Structural studies of the free nucleosides 1 and 2 revealed that both bases are oriented syn, thus mimicking the conformation of the oxopurine nucleosides. Suitably protected phosphoramidite derivatives were prepared for incorporation into synthetic DNAs, to be used as probes of DNA damage responses, and 5'-triphosphate derivatives (3 and 4) were synthesized as analogues of damaged nucleotides in the cellular nucleotide pool. Base pairing studies in 12-mer duplexes showed that 1 and 2 have low affinity for polar pairing partners, consistent with previous nonpolar DNA base analogues. However, both compounds pair with small but significant selectivity for purine partners, consistent with the idea that the syn purine geometry leads to pyrimidine-like shapes. Steady-state kinetics studies of 1 and 2 were carried out with the Klenow fragment of Escherichia coli DNA Pol I (exo-) in single-nucleotide insertions. In the DNA template, the analogues successfully mimicked the mutagenic behavior of oxopurines, with 1 being paired selectively with adenine and 2 pairing selectively with guanine. The compounds showed similar mutagenic behavior as nucleoside triphosphate analogues, being preferentially inserted opposite mutagenic purine partners. The results suggest that much of the mutagenicity of oxopurines arises from their shapes in the syn conformation rather than from electrostatic and hydrogen-bonding effects. The new analogues are expected to be generally useful as mechanistic probes of cellular responses to DNA damage.
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Affiliation(s)
- Yosuke Taniguchi
- Department of Chemistry, Stanford University, Stanford, California 94305-5080, USA
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22
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Paz-Elizur T, Ben-Yosef R, Elinger D, Vexler A, Krupsky M, Berrebi A, Shani A, Schechtman E, Freedman L, Livneh Z. Reduced repair of the oxidative 8-oxoguanine DNA damage and risk of head and neck cancer. Cancer Res 2007; 66:11683-9. [PMID: 17178863 DOI: 10.1158/0008-5472.can-06-2294] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
An increasing number of studies indicate that reduced DNA-repair capacity is associated with increased cancer risk. Using a functional assay for the removal of the oxidative DNA lesion 8-oxoguanine by the DNA-repair enzyme 8-oxoguanine DNA glycosylase 1 (OGG1), we have previously shown that reduced OGG activity is a risk factor in lung cancer. Here, we report that OGG activity in peripheral blood mononuclear cells from 37 cases with squamous cell carcinoma of the head and neck (SCCHN) was significantly lower than in 93 control subjects, frequency matched for age and gender. Retesting of OGG activity 3 to 4 years after diagnosis and successful treatment of 18 individuals who recovered from the disease showed that OGG activity values were similar to those determined at diagnosis, suggesting that reduced OGG activity in case patients was not caused by the disease. Logistic regression analysis indicated that the adjusted odds ratio (OR) associated with a unit decrease in OGG activity was statistically significantly increased [OR, 2.3; 95% confidence interval (95% CI), 1.5-3.4]. Individuals in the lowest tertile of OGG activity exhibited an increased risk of SCCHN with an OR of 7.0 (95% CI, 2.0-24.5). The combination of smoking and low OGG was associated with a highly increased estimated relative risk for SCCHN. These results suggest that low OGG is associated with the risk of SCCHN, and if confirmed by additional epidemiologic studies, screening of smokers for low OGG activity might be used as a strategy for the prevention of lung cancer and SCCHN.
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Affiliation(s)
- Tamar Paz-Elizur
- Department of Biological Chemistry, Weizmann Institute of Science, Rehovot, Israel
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23
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Paz-Elizur T, Elinger D, Leitner-Dagan Y, Blumenstein S, Krupsky M, Berrebi A, Schechtman E, Livneh Z. Development of an enzymatic DNA repair assay for molecular epidemiology studies: distribution of OGG activity in healthy individuals. DNA Repair (Amst) 2006; 6:45-60. [PMID: 16982217 DOI: 10.1016/j.dnarep.2006.08.003] [Citation(s) in RCA: 90] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2006] [Revised: 08/03/2006] [Accepted: 08/15/2006] [Indexed: 10/24/2022]
Abstract
While the role of reduced DNA repair in susceptibility to hereditary cancers is well established, its role in sporadic cancer is less understood. One of the reasons is the lack of specific DNA repair assays that are suitable for epidemiology studies. Here we describe the development of the OGG test, an epidemiology-grade enzymatic assay for the activity of the base excision repair enzyme 8-oxoguanine DNA glycosylase, in protein extracts prepared from human blood cells. The assay is robust and reproducible, with a coefficient of variation of 10%. Using the OGG test we determined OGG activity in 120 healthy individuals. Our results show an inter-individual variation of 2.8-fold in OGG activity, from 3.6 up to 10.1units/microg protein, with a mean value of 7.2units/microg protein. There was no significant difference in OGG activity between males and females, or between smokers and non-smokers. Interestingly, there was a gender-specific effect of age: OGG activity was slightly but significantly lower in males older than the age of 55 years compared to younger males, but not in females at the same age groups. Analysis of OGG1 mRNA by quantitative real-time RT-PCR showed a group trend of an increase in OGG enzymatic activity with increasing mRNA expression, but the correlation between activity and mRNA in individuals was poor, indicating the importance of factors other than mRNA expression. The OGG test described is expected to be useful in studying the role of 8-oxoguanine repair in cancer, as recently demonstrated for non-small cell lung cancer [T. Paz-Elizur, M. Krupsky, S. Blumenstein, D. Elinger, E. Schechtman, Z. Livneh, J. Natl. Cancer Inst. 95 (2003) 1312-1319]. In addition, it may serve as a paradigm for the development of additional functional DNA repair tests, which are needed in order to gain further insight into the role of DNA repair in cancer risk and pathology.
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Affiliation(s)
- Tamar Paz-Elizur
- Department of Biological Chemistry, Weizmann Institute of Science, Rehovot 76100, Israel
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