Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0596263 (carcinogenesis)
 64,820 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The XRCC1 protein is involved in the base excision repair pathway through interactions with other proteins. Polymorphisms in the XRCC1 gene may lead to variation in repair proficiency and confer inherited predisposition to cancer. We prospectively assessed the associations between polymorphisms and haplotypes in XRCC1 and breast cancer risk in a nested case-control study within the Nurses' Health Study (incident cases, n = 1004; controls, n = 1385). We further investigated gene-environment interactions between the XRCC1 variations and plasma carotenoids on breast cancer risk. We genotyped four haplotype-tagging single nucleotide polymorphisms (Arg(194)Trp, C26602T, Arg(399)Gln, and Gln(632)Gln) in the XRCC1 gene. Five common haplotypes accounted for 99% of the chromosomes in the present study population of mostly Caucasian women. We observed a marginally significant reduction in the risk of breast cancer among (194)Trp carriers. As compared with no-carriers, women with at least one (194)Trp allele had a multivariate odds ratio of 0.79 (95% of the confidence interval, 0.60-1.04). The inferred haplotype harboring the (194)Trp allele was more common in controls than in cases (6.6 versus 5.3%, P = 0.07). We observed that the Arg(194)Trp modified the inverse associations of plasma alpha-carotene level (P, ordinal test for interaction = 0.02) and plasma beta-carotene level (P, ordinal test for interaction = 0.003) with breast cancer risk. No suggestion of an interaction was observed between the Arg(194)Trp and cigarette smoking. Our results suggest an inverse association between XRCC1 (194)Trp allele and breast cancer risk. The findings of the effect modification of the Arg(194)Trp on the relations of plasma alpha- and beta-carotene levels with breast cancer risk suggest a potential protective effect of carotenoids in breast carcinogenesis by preventing oxidative DNA damage.
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PMID:A prospective study of XRCC1 haplotypes and their interaction with plasma carotenoids on breast cancer risk. 1467 22

We analysed the associations between genetic polymorphisms in genes coding for DNA repair enzymes XPD (exon 23 A --> C, K751Q), XPG (exon 15 G --> C, D1104H), XPC (exon 15 A --> C, K939Q), XRCC1 (exon 10 G --> A, R399Q) and XRCC3 (exon 7 C --> T, T241 M) and the levels of chromosomal aberrations (CAs) and single-strand breaks (SSBs) in peripheral lymphocytes in a central European population. We also measured the irradiation-specific DNA repair rates and the repair rates of 8-oxoguanines in these individuals. An elevated frequency of CAs was observed in individuals with the XPD exon 23 A allele (AA and AC) genotypes (F = 3.6, P = 0.028, ANOVA). In multifactorial analysis of variance, the XPD exon 23 polymorphism appeared as a major factor influencing CAs (F = 4.2, P = 0.017). SSBs in DNA, on the other hand, were modulated by XPD (F = 4.3, P = 0.023), XPG (F = 4.3, P = 0.024) and XRCC1 genotypes (F = 3.0, P = 0.064). Irradiation-specific DNA repair rates (reflecting mainly base excision repair activity) were affected by XRCC1 (F = 5.9, P = 0.010) and XPC polymorphisms (F = 4.2, P = 0.046, MANOVA). Our results from this study suggest that markers of genotoxicity are associated with polymorphisms in genes encoding DNA repair enzymes.
Carcinogenesis 2004 May
PMID:Genetic polymorphisms in DNA repair genes and possible links with DNA repair rates, chromosomal aberrations and single-strand breaks in DNA. 1472 91

APE1 (apurinic/apyrimidinic endonuclease 1) and XRCC1 (X-ray cross-complementing group 1) are DNA repair proteins that play important roles in the base excision repair (BER) pathway. Polymorphisms in their encoding genes are associated with altered DNA repair capacity and thus may impact on cancer risk. In the present case-control study with 178 Japanese incident lung cancer cases and 449 age- and sex-matched controls, we investigated the gene-environment interaction among APE1 Asp148Glu, XRCC1 Arg399Gln and smoking habit in lung cancer risk. The results were analyzed by using conditional logistic regression models, adjusted for age, sex and smoking status. The adjusted odds ratio for the current smokers with APE1 148Asp/Asp, Asp/Glu and Glu/Glu genotype as compared with the never smokers with the Asp/Asp genotype were 3.01 (95% CI 1.39-6.51, P = 0.005), 2.73 (95% CI 1.29-5.77, P = 0.008) and 7.33 (95% CI 2.93-18.3, P < 0.001), respectively. The gene-environment interaction between current smoking and APE1 148Glu/Glu genotype was statistically significant (OR 3.59, 95% CI 1.28-10.1, P = 0.015). When APE1 Asp148Glu and XRCC1 Arg399Gln polymorphisms were evaluated together, the adjusted odds ratios for the current smokers with 0-1, 2 and 3-4 of APE1 148Glu or XRCC1 399Gln alleles as compared with never smokers with the 0 of these alleles were 2.96 (95% CI 1.57-5.58, P = 0.001), 3.86 (95% CI 1.85-8.05, P < 0.001) and 6.01 (95% CI 2.25-16.1, P < 0.001), respectively. The gene-environment interaction between current smoking and three or more APE1 148Glu or XRCC1 399Gln alleles was statistically significant (OR 2.44, 95% CI 1.00-9.22, P = 0.049). The OR for the gene-environment interaction of Glu/Glu genotype of APE1 codon 148 with heavy smoking was 1.04 (95% CI 0.38-2.90, P = 0.936) and that with light smoking was 2.67 (95% CI 1.00-7.68, P = 0.049). These results suggest that APE1 Asp148Glu and XRCC1 Arg399Gln polymorphisms might modify the risk of lung cancer attributable to cigarette smoking exposure.
Carcinogenesis 2004 Aug
PMID:Gene-environment interactions between the smoking habit and polymorphisms in the DNA repair genes, APE1 Asp148Glu and XRCC1 Arg399Gln, in Japanese lung cancer risk. 1504 28

Cigarette smoking is the major cause of bladder cancer. Constituents in tobacco smoke can induce oxidative DNA damage requiring base excision repair. The Arg399Gln polymorphism in the DNA base excision repair gene XRCC1 is associated with several phenotypic markers of reduced DNA repair capacity. Results from several epidemiologic studies suggest that the Arg399Gln polymorphism may influence susceptibility to several cancers including bladder cancer; however, data from large population-based studies are lacking. In a population-based case-control study from New Hampshire, we observed a reduced risk among those homozygous for the Arg399Gln XRCC1 variant polymorphism compared with those with one or two wild-type alleles (odds ratio 0.6, 95% confidence interval 0.4-1.0). There was no indication of a gene-environment interaction between cigarette smoking and the variant genotype. Our data are consistent with a potential role of the XRCC1 Arg399Gln polymorphism in bladder cancer susceptibility and further suggest that there may be DNA lesions important in bladder carcinogenesis, repaired by the base excision repair mechanism, that are not directly associated with tobacco smoking.
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PMID:A population-based case-control study of the XRCC1 Arg399Gln polymorphism and susceptibility to bladder cancer. 1529 55

Several polymorphisms in DNA repair genes have been reported to be associated with lung cancer risk including XPA (-4G/A), XPD (Lys751Gln and Asp312Asn), XRCC1 (Arg399Gln), APE1 (Asp148Glu) and XRCC3 (Thr241Met). As there is little information on the combined effects of these variants, polymorphisms were analyzed in a case-control study including 463 lung cancer cases [among them 204 adenocarcinoma and 212 squamous cell carcinoma (SCC)] and 460 tumor-free hospital controls. Odds ratios (OR) adjusted for age, gender, smoking and occupational exposure were calculated for the variants alone and combinations thereof. For homozygous individuals carrying the Glu variant of APE1, a protective effect was found (OR = 0.77, CI = 0.51-1.16). Individuals homozygous for the variants XPA (-4A) (OR = 1.53, CI = 0.94-2.5), XPD 751Gln (OR = 1.39, CI = 0.90-2.14) or XRCC3 241Met (OR = 1.29, CI = 0.85-1.98) showed a slightly higher risk for lung cancer overall. In the subgroup of adenocarcinoma cases, adjusted ORs were increased for individuals homozygous for XPA (-4A) (OR = 1.62, CI = 0.91-2.88) and XRCC3 241Met (OR = 1.65; CI = 0.99-2.75). When analyzing the combined effects of variant alleles, 54 patients and controls were identified that were homozygous for two or three of the potential risk alleles [i.e. the variants in nucleotide excision repair, XPA (-4A) and XPD 751Gln, and in homologous recombination, XRCC3-241Met]. ORs were significantly increased when all patients (OR = 2.37; CI = 1.26-4.48), patients with SCC (OR = 2.83; CI = 1.17-6.85) and with adenocarcinoma (OR = 3.05; CI = 1.49-6.23) were analyzed. Combinations of polymorphisms in genes involved in the same repair pathway (XPA + XPD or XRCC1 + APE1) affected lung cancer risk only in patients with SCC. These results indicate that lung cancer risk is only moderately increased by single DNA repair gene variants investigated but it is considerably enhanced by specific combinations of variant alleles. Analyses of additional DNA repair gene interactions in larger population-based studies are warranted for identification of high-risk subjects.
Carcinogenesis 2004 Dec
PMID:Specific combinations of DNA repair gene variants and increased risk for non-small cell lung cancer. 1533 65

Lack of functional telomeres can cause chromosomal aberrations. This type of genetic instability may promote tumorigenesis. We have investigated the association between mean telomere length in buccal cells (assessed with quantitative real-time PCR) and bladder cancer risk in a case-control study. Patients with bladder cancer displayed significantly shorter telomeres than control subjects (P = 0.001). Median telomere length ratio was 0.95 (range 0.53-3.2) for cases and 1.1 (0.51-2.4) for controls. Moreover, the adjusted odds ratio (OR) for bladder cancer was significantly increased in the quartile with the shortest telomere length OR = 4.5 [95% confidence interval (CI) 1.7-12]. It is known that oxidative stress, alkylation or UV radiation increases shortening of telomeres. Therefore, we also analyzed whether environmental and genetic factors associated with DNA damage, i.e. smoking and polymorphisms in the genes involved in the metabolism of genotoxic carcinogens (EPHX1, GSTA1, GSTM1, GSTP1, GSTT1, NAT1, NAT2 and NQO1) or DNA repair (APE1, NBS1, XPC, XPD, XRCC1, XRCC3 and XRCC4), could modify the association between telomere length and cancer risk. A clear effect of smoking and telomere length could be observed. Current smokers with short telomeres had more than six times as higher risk as non-smokers/former smokers with long telomeres (OR = 6.3, 95% CI 1.7-23). Lack of the biotransformation gene GSTM1 and short telomeres were associated with OR = 6.5 (95% CI 2.4-18), whereas homozygous carriers of 312Asn in the DNA repair gene XPD, with short telomeres, displayed an OR of 17 (95% CI 1.9-150). However, no significant interaction for cancer risk could be proven for telomere length, smoking and susceptibility genotypes of metabolizing and DNA-repairing genes.
Carcinogenesis 2005 Jul
PMID:Constitutional short telomeres are strong genetic susceptibility markers for bladder cancer. 1574 60

A wide variety of base damages and single-strand breaks formed by reactive oxygen species during metabolic activation of polycyclic aromatic hydrocarbons (PAHs) have been recognized to be involved in PAH carcinogenesis. In this study, alkaline comet assay was used to detect the DNA damage in peripheral blood lymphocytes among 143 coke-oven workers and 50 non-coke-oven workers, and the effects of genetic polymorphisms of XRCC1 and ERCC2 genes on DNA damage were evaluated. The olive tail moment was significantly higher in coke-oven workers than in non-coke-oven workers (2.6, 95% CI=2.1-3.3 versus 1.0, 95% CI=0.8-1.2, p<0.01), and significant correlation between ln-transformed urinary 1-OHP and ln-transformed olive tail moment was found in total population (n=193, Pearson's r=0.393, p<0.001) and in coke-oven workers (n=143, Pearson's r=0.224, p=0.007). The olive tail moment was significantly higher in coke-oven workers with GA genotype of G27466A polymorphism of XRCC1 than those with GG genotype (4.6, 95% CI=2.5-8.7 versus 2.4, 95% CI=1.9-2.9, p<0.01 with adjustment for covariates). No significant associations between C26304T, G28152A and G36189A polymorphisms of XRCC1 and G23591A and A35931C polymorphisms of ERCC2 and olive tail moment were found in both groups. The study showed that the alkaline comet assay is a suitable biomarker in the detection of DNA damage among coke-oven workers and it suggested that the A allele of G27466A polymorphism of XRCC1 may be associated with decreased DNA repair capacity toward PAH-induced base damage and strand breaks.
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PMID:Associations between XRCC1 and ERCC2 polymorphisms and DNA damage in peripheral blood lymphocyte among coke oven workers. 1576 1

Whereas animal and in vitro studies support a role of unsaturated fatty acids in colon carcinogenesis, the epidemiologic evidence is inconclusive. Using a large sigmoidoscopy-based case-control study (753 cases and 799 controls) in Los Angeles County, we investigated possible associations between single-nucleotide polymorphisms in the XRCC1 (codons 194 Arg/Trp and codon 399 Arg/Gln) and XRCC3 (codon 241 Thr/Met) genes and colorectal adenoma risk and their possible role as modifiers of the effect of monounsaturated fatty acid, the ratio of omega-6/omega-3 polyunsaturated fatty acids, and antioxidant intake. We found no evidence of associations between the XRCC1 codon 194 Arg/Trp or Trp/Trp genotypes and the XRCC3 codon 241 Thr/Met or Met/Met genotypes. Subjects with the XRCC1 Gln/Gln genotype were inversely associated with adenoma risk (odds ratio, 0.6; 95% confidence interval, 0.4-0.9; P = 0.01) when compared with subjects with Arg/Arg and Arg/Gln genotypes combined. We found no evidence of gene-dietary fat interactions for the XRCC3 codon 241 polymorphism. However, our data suggest an XRCC1-unsaturated fat interaction. High monounsaturated fatty acid intake was associated with adenoma risk only among subjects with the XRCC1 codon 194 Arg/Arg and codon 399 Gln/Gln combined genotypes (P for interaction = 0.018). High omega-6/omega-3 polyunsaturated fatty acid ratios were associated with adenoma risk among subjects with the XRCC1 codon 194 Arg/Arg and codon 399 Gln/Gln or the codon 194 Arg/Trp or Trp/Trp and codon 399 Arg/Arg or Arg/Gln combined genotypes (P for interaction = 0.026). These interactions were not modified by antioxidant intake. However, low antioxidant intake was associated with an inverse association only among subjects with the XRCC1 codon 194 Arg/Trp or Trp/Trp and codon 399 Arg/Arg or Arg/Gln combined genotypes (P for interaction = 0.022), which was independent of unsaturated fat intake. Our data suggest that the XRCC1 codon 194 and codon 399 single nucleotide polymorphisms may modify the effect of unsaturated fatty acid and antioxidant intake and that this XRCC1 effect modification may explain, in part, previously reported inconsistencies on the role of unsaturated fatty acids and adenoma risk.
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PMID:XRCC1 and XRCC3 polymorphisms and their role as effect modifiers of unsaturated fatty acids and antioxidant intake on colorectal adenomas risk. 1576 38

Inherited polymorphisms in the genes controlling the cell cycle or functioning in the DNA repair mechanisms may impair their function and contribute to genetic susceptibility. Abnormalities in the DNA repair have been reported in head and neck cancer. The XRCC1 gene functions in singlestrand break and base excision repair processes. In this study, two polymorphisms of the XRCC1 gene, Arg194Trp and Arg399Gln were investigated in 95 patients with head and neck carcinoma. The polymorphic regions were amplified by PCR followed by digestion with methylation-specific restriction enzymes, and analyzed electrophoretically. Genotype and allele frequencies were calculated, and association with cancer risk or clinical parameters was investigated. No association was observed between the genotypes and head and neck cancer for either polymorphism. Distribution of the alleles did not significantly differ between the patients and the control group. A significant association was only found for the Trp194 allele among the smoking individuals. Our data indicate that the Arg194Trp and Arg399Gln polymorphisms do not confer a significant risk for head and neck carcinogenesis.
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PMID:Polymorphisms of the XRCC1 DNA repair gene in head and neck cancer. 1580 Jun 78

Impaired DNA repair capacity may adversely affect cancer risk, particularly in subjects exposed to DNA damaging carcinogens, as found in tobacco smoke, or among subjects deficient for protective factors, as found in fruits and vegetables. We studied tobacco use, fruit and vegetable intake, and common non-synonymous single nucleotide polymorphisms in four DNA repair genes in relation to gastric cancer risk, in a population-based, case-control study of 281 incident gastric cancer cases and 390 controls, in Warsaw, Poland. Multivariate logistic regression analysis was performed to calculate odds ratios (OR) and 95% confidence intervals (CI). Increased risks of gastric cancer were found for smokers (OR=3.1, CI=1.9-5.1 for pack-years>or=40 versus never smokers) and subjects with low fruit intake (OR=2.2, CI=1.3-3.6 for 1st versus 4th quartile); risk associated with vegetable intake was not statistically significant. Allele frequencies among the controls were consistent with those previously reported for the 5 polymorphisms studied: XRCC1-Arg399Gln, XPD-Lys751Gln, MGMT-Ile143Val, Leu84Phe, and XRCC3-Thr241Met. None of the studied polymorphisms were independently associated with gastric cancer risk. Smoking-associated risks, however, were greatest for carriers of the XRCC1-399 ArgArg genotype (Pinteraction=0.004). Risks associated with low intake of fruits or vegetables tended to be modified by selected polymorphisms in XRCC1, XPD and MGMT (Pinteraction=0.1-0.2). Risk modification was not found for the other repair polymorphisms. Selected DNA repair polymorphisms did not have independent effects on gastric cancer risk; however, they may modify smoking- and probably diet-related risks for this disease. These results need replication in larger epidemiological studies of gastric cancer.
Carcinogenesis 2005 Aug
PMID:Selected DNA repair polymorphisms and gastric cancer in Poland. 1580 98


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