An updated meta-analysis between the association of XRCC1 Arg399Gln polymorphism and hepatocellular carcinoma risk

Background: Various studies have evaluated the relationship between X-ray repair cross-complementinggroup 1 (XRCC1) Arg399Gln polymorphism and hepatocellular carcinoma (HCC) risk, but the conclusionshave been inconsistent and underpowered. The purpose of this updated meta-analysis was to examine whetherXRCC1 Arg399Gln polymorphism confers susceptibility to HCC. Methods: Eligible studies extracted fromPubMed, Embase, Cochrane Library, VIP (chinese) and CNKI (chinese) up to November 2013 were included inthe study. Pooled odds ratio (OR) together with their 95% confidence interval (CI) were estimated to evaluateXRCC1 Arg399Gln polymorphism and HCC risk. Results: Finally, 21 studies with 4,170 cases and 5,030controls were involved in our meta-analysis. The results demonstrated that there was significant associationbetween Arg399Gln polymorphism and HCC risk under two contrast models in overall populations (AG vs GG:OR=1.265, 95%CI=1.036-1.545, p=0.021; AA+AG vs GG: OR=1.240, 95%CI=1.021-1.506, p=0.030). In subgroupanalyses, significant association was found in Asians (A vs G: OR=1.175, 95%CI=1.013-1.362, p=0.033; AG vsGG: OR=1.317, 95%CI=1.070-1.622, p=0.009; AA+AG vs GG: OR=1.289, 95%CI=1.055-1.575, p=0.013) andCaucasians (A vs G: OR=0.591, 95%CI=0.361-0.966, p=0.036; AA+AG vs GG: OR=0.468, 95%CI=0.234-0.934,p=0.031). Conclusions: The results suggest that XRCC1 Arg399Gln polymorphism may increase HCC riskespecially among Asians. However, XRCC1 Arg399Gln polymorphism might act as a protective role againstHCC among Caucasians.     

XRCC1 Arg399Gln基因多态性与中国人群肝细胞癌易感性的Meta分析

目的 探讨XRCC1 Arg399Gln基因多态性与肝细胞癌（HCC）易感性的关系。方法 计算机检索PubMed、中国生物医学文献（CBM）、中国知网、万方及维普等数据库,收集有关XRCC1 Arg399Gln基因多态性与HCC易感性关系的病例对照研究,提取纳入文献的相关数据进行Meta分析,以病例组与对照组XRCC1 Arg399Gln各种基因模型的比值比（OR）为效应指标,发表偏倚采用Eggers检验和Beggs检验。结果 共17篇文献符合纳入标准,累计病例数3301例,对照组4156例。XRCC1 Arg399Gln基因多态性与中国人群HCC易感性有明显关联性（G/G vs. A/A：OR=1.32,95％CI：1.13～1.54,P=0.000;A/G vs. A/A：OR=1.25,95％CI：1.10～1.41,P=0.000;A/G+G/G vs. A／A：OR=1.22,95％CI：1.09～1.36,P=0000;G／G vs. A／A+A／G：OR=1.20,95％CI：1.04～1.39,P=0.014）。根据健康对照组来源不同的亚组分析中,所有地区或者控制人口来源医院的研究结果均显示,XRCC1 Arg399Gln 基因多态性与HCC易感性有明显关联性,但控制人口非医院来源的研究结果显示XRCC1 Arg399Gln 基因多态性与HCC易感性无明显关联性;根据地区不同分组的亚组分析中,在广西地区,除隐性遗传模型外（G/G vs. A/A+A/G：OR=1.25,95％CI：0.95～1.65,P=0.115）,其余遗传模型结果显示XRCC1 Arg399Gln基因多态性与广西地区HCC易感性有明显相关性（G/G vs. A/A：OR=1.47,95％CI：1.10～1.95,P=0.009;A/G vs. A/A：OR=1.35,95％CI：1.17～1.56,P=0.000;A/G+G/G vs.A／A：OR=133,95％CI：1.16～1.52,P=0.000）。结论 XRCC1 Arg399Gln 基因多态性可能增加中国人群HCC的易感性,尤其在广西地区。     

An Updated Meta-analysis on the Association of X-Ray Repair Cross Complementing Group 1 Codon 399 Polymorphism with Hepatocellular Carcinoma Risk

Background: A number of studies have reported the association of X-ray repair cross-complementing group1 (XRCC1) Arg399Gln polymorphism with susceptibility to hepatocellular carcinoma (HCC). However, theresults were inconsistent and inconclusive. The aim of this study was to comprehensively explore the associationof XRCC1 Arg399Gln variant with HCC risk. Materials and Methods: Systematic searches of PubMed, Elsevier,Science Direct, CNKI and Chinese Biomedical Literature Database were performed. Pooled odds ratio (OR)with 95% confidence intervals (CI) was calculated to estimate the strength of association. Results: Overall,we observed an increased HCC risk among subjects carrying XRCC1 codon 399 Gln/Gln, Arg/Gln and Gln/Gln+Arg/Gln genotypes (OR=1.20, 95%CI: 1.05-1.38, OR=1.16, 95%CI: 1.05-1.28, and OR=1.14, 95%CI:1.04-1.24, respectively) based on 20 studies including 3374 cases and 4633 controls. In subgroup analysis, weobserved an increased risk of XRCC1 codon 399 Gln/Gln, Arg/Gln and Gln/Gln+Arg/Gln polymorphisms forHCC in hospital-based study (OR=1.25, 95%CI: 1.03-1.51, OR=1.21, 95%CI: 1.07-1.36 and OR=1.18, 95%CI:1.06-1.31, respectively) and in Asian population (OR=1.19, 95%CI: 1.03-1.38, OR=1.17, 95%CI: 1.04-1.30 andOR=1.14, 95%CI: 1.04-1.25, respectively). Limiting the analysis to the studies with controls in agreement withHardy-Weinberg equilibrium (HWE), we observed an increased HCC risk among Gln/Gln, Arg/Gln and Gln/Gln+Arg/Gln genotype carriers (OR=1.17, 95%CI: 1.05-1.29, OR=1.12, 95%CI: 1.00-1.25 and OR=1.11, 95%CI:1.02-1.21, respectively). Conclusions: This updated meta-analysis results suggest that XRCC1 Arg399Gln variantsmay contribute to HCC risk. Well-designed studies with larger sample size were required to further verify ourfindings.     

Evaluation of DNA repair gene XRCC1 polymorphism in prediction and prognosis of hepatocellular carcinoma risk

We conducted a case-control study in China to clarify the association between XRCC1-Arg399Gln polymorphism and HCC risk. A total of 150 cases and 158 controls were selected from the the Affiliated Hospital of Qingdao University from May 2008 to May 2010. XRCC1-Arg399Gln polymorphism was based upon duplex polymerase-chain-reaction with the confronting-two-pair primer (PCR-CTPP) method. All analyses were performed using the STATA statistical package. A significantly increased risk was associated with the Arg/Gln genotype (adjusted OR 1.78, 95%CI=1.13-2.79) compared with genotype Arg/Arg. In contrast, the Gln/Gln genotype had non-significant increased risk of HCC with adjusted OR (95%CI) of 1.69 (0.93-2.66). A significant association was found between positive HBsAg and Arg/Gln, with an OR of 3.43 (95% CI=1.45-8.13). Patients carrying Gln/Gln genotypes showed significantly lower median survival than Arg/Arg genotypes (HR=1.38, 95% CI=1.04-1.84). Further Kaplan-Meier analysis showed decreased median survival in Arg/Gln+Gln/Gln genotype carriers in comparison to Arg/Arg carriers (HR=1.33, 95% CI=1.02-1.76). In conclusion, we observed that XRCC1-Arg399Cln polymorphism is associated with susceptibility to HCC, and XRCC1 Gln allele genotype showed significant prognostic associations.     

Polymorphisms of DNA repair gene XRCC1 and hepatocellular carcinoma risk among East Asians: a meta-analysis

Association studies on the X-ray repair cross-complementing group 1 (XRCC1) polymorphisms (Arg194Trp, Arg280His, and Arg399Gln) in hepatocellular carcinoma (HCC) have shown conflicting results. The aim of this study was to quantitatively summarize the evidence for such a relationship. Published literatures from PubMed, Embase, CNKI, and Chinese Biomedicine Database were retrieved. Pooled odds ratio (OR) with 95 % confidence interval (CI) was calculated using fixed- or random-effects model. Thirteen studies including 3,011 HCC cases and 3,619 controls were included in the meta-analysis of the association between XRCC1 Arg399Gln polymorphism and HCC risk. The results indicated that Arg399Gln polymorphism was significantly associated with risk of HCC in a codominant model (Gln/Gln vs. Arg/Arg, OR?=?1.32, 95 % CI?=?1.08–1.61; Arg/Gln vs. Arg/Arg, OR?=?1.41, 95 % CI?=?1.12–1.80) and a dominant model (Gln/Gln?+?Arg/Gln vs. Arg/Arg, OR?=?1.39, 95 % CI?=?1.15–1.69), but not in a recessive model (Gln/Gln vs. Arg/Gln?+?Arg/Arg, OR?=?1.13, 95 % CI?=?0.95–1.35). Limiting the analysis to the studies within Hardy–Weinberg equilibrium, the results were persistent and robust. When stratifying for region and source of controls, persistent results were observed in any subgroup. No evidence of association of Arg194Trp (980 HCC cases and 966 controls) and Arg280His (1,200 HCC cases and 1,236 controls) with HCC risk was found. No publication bias was found in the present study. The results from the present meta-analysis indicated that the Arg399Gln polymorphisms of XRCC1 may be a genetic susceptibility for HCC in the East Asian population. Further, large and well-designed studies are needed to confirm this conclusion.     

X-ray repair cross-complementing group 1 Arg399Gln gene polymorphism and susceptibility to colorectal cancer:a meta-analysis

X-ray repair cross-complementing group 1 (XRCC1), a DNA repair enzyme, plays a crucial role in the base excision repair by generating a single nucleotide repair patch. It has been demonstrated that the XRCC1 Arg399Gln gene polymorphism was associated with variations in XRCC1 enzyme activity. The aim of this study was to quantitatively summarize the association between the XRCC1 Arg399Gln polymorphism and susceptibility to colorectal cancer (CRC). A comprehensive search of the PubMed, Embase, and China National Knowledge Infrastructure databases was conducted for studies on the association between the XRCC1 Arg399Gln polymorphism and CRC risk. Summary odds ratio (OR) with its corresponding 95 % confidence interval (95 %CI) was estimated, in a fixed-effects model or a random-effects model when appropriate, to assess the association. Totally, 26 case–control studies with 6,979 cases and 11,470 controls were included into this meta-analysis. The pooled results of total studies showed that the XRCC1 Arg399Gln polymorphism was significantly associated with increased risk of CRC in all genetic contrast models (OR_{A vs. G}?=?1.13, 95 %CI 1.03–1.23, P _OR?=?0.008; OR_{Gln/Gln vs. Arg/Arg}?=?1.24, 95 %CI 1.04–1.46, P _OR?=?0.015; OR_{Gln/Gln vs. Arg/Gln + Arg/Arg}?=?1.19, 95 %CI 1.03–1.38, P _OR?=?0.021; OR_{Gln/Gln + Arg/Gln vs. Arg/Arg}?=?1.14, 95 %CI 1.02–1.28, P _OR?=?0.022), except for the additive contrast model (OR_{Arg/Gln vs. Arg/Arg}?=?1.11, 95 %CI 0.99–1.25, P _OR?=?0.064). The statistically significant association between the XRCC1 Arg399Gln polymorphism and CRC risk was observed among studies with high quality and in Asians, but not in Caucasians. Sensitivity analyses by sequential omission of any individual studies further identified the significant association. Publication bias was inexistent in this meta-analysis. The meta-analysis suggests that the XRCC1 Arg399Gln polymorphism is associated with increased risk of CRC.     

Updated Assessment of the Association of the XRCC1 Arg399Gln Polymorphism with Lung Cancer Risk in the Chinese Population

Background: Published studies have reported relationships between X-ray repair cross-complementing group1 (XRCC1) Arg399Gln polymorphism and lung cancer risk in Chinese population. However, the epidemiologicalresults remained controversial. The objective of this study was to clarify the association of XRCC1 Arg399Glnpolymorphism with lung cancer risk in the Chinese population. Materials and Methods: Systematic searches wereperformed through the database of Medline/Pubmed, Web of Science, Embase, CNKI and WanFang MedicalOnline. Odds ratios (ORs) with 95% confidence interval (95%CI) were calculated to estimate the strength ofthe association. Results: Overall, we observed an increased lung cancer risk among subjects carrying XRCC1codon 399 Gln/Gln genotype (OR=1.36, 95%CI: 1.09-1.71) in the Chinese population on the basis of 19 studieswith 5,416 cases and 5,782 controls. We did not observe any association between XRCC1 codon 399 Arg/Gln andArg/Gln+Gln/Gln polymorphisms and lung cancer risk (OR=1.00, 95%CI: 0.92-1.08 and OR=1.05, 95%CI: 0.97-1.13, respectively). Limiting the analysis to studies with controls in agreement with Hardy-Weinberg equilibrium(HWE), we observed an increased lung cancer risk among subjects carrying XRCC1 codon 399 Gln/Gln genotype(OR=1.18, 95%CI: 1.01-1.38). When stratified by source of control, we observed an increased lung cancer riskamong subjects carrying XRCC1 codon 399 Arg/Gln+Gln/Gln genotype on the basis of hospitalized patient-basedcontrols (OR=1.21, 95%CI: 1.04-1.42) and among subjects carrying XRCC1 codon 399 Gln/Gln genotype onthe basis of healthy subject-based controls (OR=1.22, 95%CI: 1.04-1.43). Conclusions: Our findings indicatedthat certain XRCC1 Arg399Gln variants might affect the susceptibility of lung cancer in Chinese population.Larger sample size studies are required to confirm our findings.     

X-Ray Repair Cross-Complementing Group 1(XRCC1) Genetic Polymorphisms and Thyroid Carcinoma Risk: a Meta-Analysis

A number of studies have been conducted to explore the association of XRCC1 polymorphisms with thyroidcancer risk, but the results have been inconsistent. Thus we performed the present meta-analysis to clarify thisissue based on all of the evidence available to date. Relevant studies were retrieved by searching PubMed andstatistical analysis conducted using Stata software. Nine studies were included in this meta-analysis (1,620 casesand 3,557 controls). There were 6 studies (932 cases and 2,270 controls) of the Arg194Trp polymorphism, 7 studies(1432 cases and 3356 controls) of the Arg280His polymorphism and 9 studies (1,620 cases and 3,557 controls) forthe Arg399Gln polymorphism. No association of XRCC1 Arg194Trp, Arg280His and Arg399Gln polymorphismwith thyroid cancer risk was observed in the overall analysis. However, subgroup analysis revealed: 1) anelevated risk in aa vs AA analysis (OR=2.03, 95%CI= 1.24-3.31) and recessive genetic model analysis (OR=1.93,95%CI= 1.20-3.08) in the larger sample size trials for XRCC1 Arg194Trp polymorphism; 2) a decreased thyroidcancer risk on subgroup analysis based on ethnicity in Aa vs AA analysis (OR=0.84, 95%CI= 0.72-0.98) and ina dominant genetic model (OR=0.84, 95%CI= 0.72-0.97) in Caucasian populations for the XRCC1 Arg399Glnpolymorphism; 3) a decreased thyroid cancer risk on subgroup analysis based on design type in Aa vs AA analysis(OR=0.72, 95% CI= 0.54-0.97) among the PCC trials for the Arg399Gln polymorphism. Our results suggest thatthe XRCC1 Arg399Gln polymorphism may be associated with decreased thyroid cancer risk among Caucasiansand XRCC1 Arg194Trp may be associated with a tendency for increased thyroid cancer risk in the two largersample size trials.     

XRCC1 Polymorphisms are Associated with Cervical Cancer Risk and Response to Chemotherapy: a Systematic Review and Meta-analysis

Background: Functional single nucleotide polymorphisms of x-ray repair cross-complementing protein1 (XRCC1) have been suspected to contribute to uterine cervical cancer risk for a long time; however, mostprevious case-control studies were small sized and biased. Additionally, recent studies suggested that XRCC1polymorphisms could be a biomarker of response to platinum-based chemotherapy. Methods: A comprehensivesearch was conducted to retrieve eligible studies and odds ratios (ORs) and 95% confidence intervals (95% CIs)were calculated to measure association strength. Results: A total of 13 studies were identified and analyzed. Wefound that the Arg194Trp polymorphism (Trp vs. Arg, OR=1.342, 95% CI: 1.176) was associated with increasedrisk of cervical cancer, while no significant association was found with Arg280His (His vs. Arg, OR=1.059, 95%CI: 0.863, 1.299) or Arg399Gln (Gln vs. Arg, OR=1.144, 95% CI: 0.938, 1.394). As for response to platinumbasedchemotherapy, the variant XRCC1 399Gln allele (Gln vs. Arg, OR=0.345, 95% CI: 0.163, 0.729) waslinked with a poor response; however, the Arg194Trp polymorphism (TrpArg vs. ArgArg, OR=6.421, 95% CI:1.573, 26.205) predicted a good response. Conclusion: The Arg194Trp polymorphism of XRCC1 increases riskof cervical cancer; the variant 399Gln allele predicts poor response to platinum-based chemotherapy, while theArg194Trp polymorphism indicates a good response.     

Association of XRCC1 Arg399Gln Polymorphism with Colorectal Cancer Risk: A HuGE Meta Analysis of 35 Studies

Background: Non-synonymous polymorphisms in XRCC1 hase been shown to reduce effectiveness of DNArepair and be associated with risk of certain cancers. In this study we aimed to clarify any association betweenXRCC1 Arg399Gln and colorectal cancer (CRC) risk by performing a meta-analysis of published case-controlstudies. Materials and Methods: PubMed and Google Scholar were searched to explore the association betweenXRCC1 and CRC. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to estimate theassociation strength. Publication bias was assessed by Egger’s and Begg’s tests. Results: Up to January 2015, 35case control studies involving 9,114 CRC cases and 13,948 controls were included in the present meta-analysis.The results showed that the Arg399Gln polymorphism only under an allele genetic model was associated withCRC risk (A vs. G: OR 0.128, 95% CI 0.119-0.138, p<0.001). Also, this meta-analysis suggested that the XRCC1Arg399Gln polymorphism might associated with susceptibility to CRC in Asians (A vs G: OR 0.124, 95% CI0.112-0.138, p<0.001) and Caucasian (A vs G: OR 0.132, 95% CI 0.119-0.146, p<0.001) only under an allele geneticmodel. Conclusions: This meta-analysis confirms the association between XRCC1 Arg399Gln polymorphismand CRC risk and suggests that the heterogeneity is not strongly modified by ethnicity and deviation from theHardy-Weinberg equilibrium.     

XRCC1 Arg399Gln variation and leukemia susceptibility: evidence from 2,647 cases and 5,518 controls

Previous reports implicate XRCC1 Arg399Gln polymorphism as a possible risk factor for several cancers. Increasing studies have been conducted on the association of XRCC1 Arg399Gln polymorphisms with susceptibility to leukemia. However, conflicting results have been generated. The goal of the present study was to derive a more precise estimation of the relationship. Meta-analyses assessing the association of XRCC1 Arg399Gln variation with leukemia were conducted, and subgroup analyses on ethnicity and clinical types were further performed. Eligible studies were identified for the period up to February 2013. Consequently, 16 publications including 17 case–control studies with 2,647 cases and 5,518 controls were selected for analysis. The overall data indicated a significant association of XRCC1 Arg399Gln polymorphism with leukemia risk (Gln/Gln versus Arg/Arg: OR?=?1.37, 95% confidence interval (CI)?=?1.08–1.74; dominant model: OR?=?1.23, 95%CI?=?1.03–1.46; recessive model: OR?=?1.23, 95%CI?=?1.06–1.44). In the subgroup analysis by ethnicity, Gln allele may increase leukemia susceptibility among Asians (Gln/Gln versus Arg/Arg: OR?=?1.82, 95%CI?=?1.19–2.78; dominant model: OR?=?1.53, 95%CI?=?1.00–2.33; recessive model: OR?=?1.51, 95%CI?=?1.11–2.06), but not Caucasians or mixed ethnicities. In the subgroup analysis by clinical types, increased risk was observed in acute lymphocytic leukemia (ALL) subgroup (Gln/Gln versus Arg/Arg: OR?=?1.45, 95%CI?=?1.09–1.93; recessive model: OR?=?1.30, 95%CI?=?1.00–1.69), but not in acute myeloid leukemia, chronic lymphocytic leukemia, or chronic myeloid leukemia subgroups, respectively. Collectively, the results of the present study suggest that XRCC1 Arg399Gln polymorphism might be a low-penetrant risk factor for leukemia, particularly among Asians. Homozygous Gln/Gln alleles might have a correlation with increased ALL susceptibility.     

广西扶绥县肝癌家系XRCC1基因Arg399Gln多态性与肝细胞癌的遗传易感性

目的研究广西扶绥县肝癌家系人群DNA修复基因XRCC1Arg399Gln多态性与肝细胞癌（HCC）遗传易感性的相关性。方法采用病例-对照研究方法,对扶绥县21个肝癌家系人群和10个正常家系人群,运用PCR-RFLP方法分析XRCC1基因Arg399Gln位点多态性,并应用Logistic回归模型分析该位点多态性与肝细胞癌遗传易感性的关系。结果通过XRCC1Arg399Gln基因型检测分型,肝癌家系人群携带变异等位基因Gln的频率为23.68%,正常家系人群为13.16%,等位基因在两组间的分布差异无统计学意义（P〉0.05）。基因型分布符合Hardy-Weinberg平衡定律。正常家系人群中携带Arg/Gln者发生HCC的风险是携带Arg/Arg者的1.622倍（95%CI=0.475～5.541,P=0.440）。肝癌家系人群中除肝癌患者外,携带Arg/Gln、Gln/Gln者发生HCC的风险分别是携带Arg/Arg者的1.198倍（95%CI=0.362～3.968）和2.964倍（95%CI=0.434～20.220,P分别为0.768、0.267）。结论广西扶绥县肝癌家系人群中,XRCC1399Arg/Gln基因型和Gln/Gln基因型者患HCC的风险较Arg/Arg基因型者有增加的趋势,但不存在显著相关性。     

Polymorphism of XRCC1 and the frequency of mutation in codon 249 of the p53 gene in hepatocellular carcinoma among Guangxi population, China

In hepatocellular carcinoma (HCC), hotspot mutation in codon 249 of the p53 gene has been associated with exposure to aflatoxin B1 (AFB1). While the polymorphism of DNA repair gene X-ray repair cross-complementary group 1 (XRCC1) Arg399Gln may be related with AFB1-DNA adducts and gene mutations. Five hundred one HCCs were included in this study to investigate the role of the XRCC1 codon 399 polymorphism on hotspot mutation in codon 249 of the p53 gene. The genotypes of XRCC1 codon 399 and p53 codon 249 were examined by PCR-RFLP. The HCC patients with XRCC1 genotypes with 399 Gln (namely: XRCC1-AG/GG) exhibited a significantly higher frequency of the p53 hotspot mutations in codon 249 than those with the wild-type homozygote of XRCC1 [namely: XRCC1-AA, adjusted odds ratio (OR) = 6.77, 95% confidence interval (CI) = 4.34-10.57]. Compared with those individuals who did express XRCC1-AA as reference (OR = 1), moreover, individuals featuring XRCC1-AG/GG and AFB1-DNA adducts did experience a significantly greater frequency of the hotspot mutation in codon 249 of the p53 gene (adjusted OR = 28.37, 95% CI = 13.19-61.02, P < 0.01). This study suggests that the XRCC1 Arg399Gln polymorphism and AFB1-DNA adducts are associated with the increased frequency of the p53 mutations in codon 249.     

Polymorphism of DNA repair gene XRCC1 and hepatocellular carcinoma risk in Chinese population

Aim: We conducted a case-control study in China to clarify the association between the XRCC1-Arg399Gln polymorphism and HCC risk. Methods: A total of 202 cases and 236 controls were selected from the the Affiliated Hospital of Qingdao University from May 2008 to May 2010. Assessment of the XRCC1-Arg399Gln polymorphism was based upon duplex polymerase-chain-reactions with the confronting-two-pair primer (PCR-CTPP) method. All analyses were performed using the STATA statistical package. Results: A significant increase in risk was associated with the Arg/Gln genotype (adjusted OR 1.55, 95%CI=1.03-2.57) compared with Arg/Arg. However, the Gln/Gln genotype had non-significant increased risk of HCC with adjusted OR (95%CI) of 1.34(0.67-2.38). There was also a significant increasewith the Arg/Gln genotype among HCC patients above 50 years old (OR=1.95, 95% CI=1.14-3.57). Additionally, the risk of HCC was moderately increased in drinkers with Arg/Gln genotype compared with never drinkers, and the adjusted OR (95% CI) was 1.89 (1.13-3.45). Conclusion: This study demonstrated that a polymorphism in a DNA repair gene may influence the risk of HCC. The XRCC1 codon Arg/Gln was thuis associated with an increased risk of HCC, especiallyin patients above 50 years old and/or with a drinking habit.     

XRCC1 Arg399Gln gene polymorphism and breast cancer risk: a meta-analysis based on case-control studies

Background: The Arg399Gln polymorphism in the XRCC1 DNA repair gene is likely to be involved with the development of breast cancer (BC). However, there have been inconsistent reports of association. The objective of this study was to systematically evaluate the published papers. Methods: We performed a meta-analysis of 44 published case-control studies fitting our eligibility criteria. These studies involved XRCC1 Arg399Gln polymorphisms in 20,841 BC cases and 22,688 controls in dominant (GlnGln+ArgGln vs. ArgArg), recessive (GlnGln vs. ArgGln+ArgArg), and co-dominant (GlnGln vs. ArgArg) inheritance models. Analyses of Asian, African and Caucasian ethnic subgroups was also conducted. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of associations. Results: Our overall analyses indicated Arg399Gln to be associated with a trend of increased BC risk when using recessive (OR=1.15, 95%CI: 1.05–1.27), and co-dominant models (OR=1.15, 95%CI: 1.04-1.27) to analyze the data. In ethnic subgroups, Arg399Gln significantly increased BC risk in Asians (OR=1.54, 95%CI: 1.18–2.01) when using recessive model analysis, in Africans (OR=1.30, 95%CI: 1.07–1.60) when using dominant model analysis, and in Asians (OR=1.50, 95%CI: 1.15–1.97) and Africans (OR=1.80, 95%CI: 1.08-3.02) when using the co-dominant model analysis. Conclusions: From our meta-analysis of data from 44 publications, we conclude that XRCC1 Arg399Gln allele is a risk factor for the development breast cancer, especially among Asian and African populations.     

X-RAY REPAIR CROSS-COMPLEMENTING GROUP 1 （XRCC1） Arg 399 Gin POLYMORPHISM AND AFLATOXIN B1 （AFB1）-RELATED HEPATOCELLULAR CARCINOMA （HCC） IN GUANGXI POPULATION

In Guangxi Zhuang Autonomous Region,Hepatocellular carcinoma(HCC)is one of the maincancer killers,the incidence rate of which is5～40/1,000,000per year.Clinic-epidemiological evidencesuggests AFB1exposure is the most cause[1].However,the exact mechanisms of AFB1hepatocarcinogenesishave not been fully elucidated.Recently,there is agrowing realization that genetic constitution is ofimportance in determining individual’s susceptibility toHCC.This genetic susceptibility may result frominhe…     

Association of XPD and XRCC1 Genetic Polymorphisms with Hepatocellular Carcinoma Risk

Aim: XRCC1 and XPD are two major repair genes involved in nucleotide excision repair (NER), whichis reported to be associated with risk of several cancers. We explored the association of XRCC1 and XPDpolymorphisms with the risk of HCC. Methods: A total of 410 cases with HCC and 410 health controls werecollected. XRCC1 Arg194Trp, XRCC1 Arg399Gln, XPD Lys751Gln and XPD Asp312Asn genotyping wasperformed by duplex polymerase-chain-reaction with the confronting-two-pair primer (PCR-CTPP) method.Results: XRCC1 194Trp/Trp was strongly significantly associated with an increased risk of HCC cancer whencompared with the wide-type genotype (OR=2.26, 95% CI=(1.23-5.38). Individuals carrying the XRCC1 399Gln/Gln showed increased risk of HCC (OR=1.74, 95%CI=1.06-2.74). The XPD 751Gln/Gln and Gln allele genotypewere associated with strong elevated susceptibility to HCC (OR=3.51 and 1.42, respectively). Conclusion: Theseresults suggest that polymorphisms in XRCC1 and XPD may have functional significance in risk of HCC.     

Assessment of the association between XRCC1 Arg399Gln polymorphism and lung cancer in Chinese

X-ray repair cross-complementing group 1 (XRCC1) is one of the major DNA repair proteins involved in the base excision repair and plays an important role in the maintenance of genomic integrity. Polymorphisms in XRCC1 may alter the function and repair capacity of XRCC1 protein which further results in the genetic instability and lung carcinogenesis. Previous studies investigating the relationship between XRCC1 Arg399Gln polymorphism and lung cancer risk in Chinese yielded contradictory results. A meta-analysis was performed to clarify the effect of XRCC1 Arg399Gln polymorphism on lung cancer. The association was assessed by calculating the pooled odds ratio (OR) with 95 % confidence intervals (95 %CI). Nineteen studies with a total of 12,835 participants were included into this meta-analysis. Overall, there was an obvious association between XRCC1 Arg399Gln polymorphism and increased risk of lung cancer under three genetic models (Gln vs. Arg: OR?=?1.13, 95 %CI 1.01–1.25, P?=?0.029; GlnGln vs. ArArg: OR?=?1.41, 95 %CI 1.07–1.84, P?=?0.013; GlnGln vs. ArArg/ArgGln: OR?=?1.37, 95 %CI 1.07–1.76, P?=?0.013). Meta-analysis of 18 studies with high quality also found that there was an obvious association between XRCC1 Arg399Gln polymorphism and increased risk of lung cancer under three genetic models. There was no obvious risk of bias in the meta-analysis. Data from the current meta-analysis support the obvious association between XRCC1 Arg399Gln polymorphism and increased risk of lung cancer in Chinese.     

Genetic Association of XRCC1 Gene rs1799782, rs25487 and rs25489 Polymorphisms with Risk of Thyroid Cancer: a Systematic Review and Meta-Analysis

Background: A number of case-control studies have evaluated associations between the X-ray cross complementary group 1 protein (XRCC1) gene rs1799782 (Arg194Trp), rs25487 (Arg399Gln) and rs25489 (Arg280His) polymorphisms and thyroid cancer (TC) risk, but the results remain inconclusive. Materials and Methods: A systematic literature search was performed using PubMed and Google Scholar Search. According to defined criteria data were extracted and pooled odds ratios with 95% confidence intervals were calculated under five genetic models. Results: A total of 8 studies with 1,672 cases and 2,805 controls for the rs1799782 polymorphism, 14 studies with 2,506 cases and 5,180 controls for the rs25487 polymorphism, and 11 studies with 2,197 cases and 4,761 controls for the rs25489 polymorphism were included in this meta-analysis. Overall, there was a statistical association between XRCC1 rs1799782 polymorphism and TC risk with the homozygote genetic model (TT vs. CC: OR = 1.815, 95% CI = 1.115-2.953, p= 0.016) and the recessive genetic model (TT vs. TC+CC: OR = 1.854, 95% CI = 1.433-2.399, p= <0.001). In the subgroup analysis by ethnicity, significantly increased TC risk was observed only in Asians under the recessive model (TT vs. TC+CC: OR = 1.816, 95% CI = 1.398-2.358, p= <0.001). In addition, there was no positive association between XRCC1 rs25487 and rs25489 polymorphisms and risk of TC. However, there was a significant association between XRCC1 rs25487 polymorphism risk of TC among Caucasians with allele genetic comparison (A vs. G: OR= 0.882, 95% CI = 0.794-0.979, p= 0.136) and dominant genetic comparison (AA+AG vs. GG: OR=0.838, 95% CI = 0.728-0.965, p= 0.014). Conclusions: The results of our meta-analysis suggest an increased risk of TC with the XRCC1 rs1799782 and rs25487 polymorphisms. However, the XRCC1 rs25489 polymorphism appeared to be without influence.     

XRCC1 polymorphisms and risk of nasopharyngeal carcinoma: a meta-analysis

Objective: Previous studies on the association between X-ray repair cross-complementing protein 1 (XRCC1) polymorphisms and nasopharyngeal carcinoma (NPC) risk showed inconsistent results. The aim of this study was to evaluate the effects of XRCC1 variants on NPC risk. Methods: A meta-analysis was performed with all eligible studies covering a total of 1,341 cases and 1,425 controls for the Arg194Trp polymorphism, 1,260 cases and 1,207 controls for the Arg280His polymorphism, and 1,644 cases and 1,678 controls for the Arg399Gln polymorphism. Results: No associations was found between Arg194Trp and Arg280His polymorphisms with NPC risk under all contrast models (co-dominant, dominant, and recessive models). However a deleterious effect of the 399Gln genotype was observed under the co-dominant model (Gln/Gln versus Arg/Arg, OR = 1.30, 95% CI : 1.01-1.69, P = 0.04). Under the recessive model (Gln/Gln versus Arg/Arg+Arg/Gln), the P value was marginally significant (OR = 1.28, 95% CI : 1.00-1.65, P = 0.05). However, the effect of the 399Gln genotype on NPC became non-significant after excluding one study from the meta-analysis because of departure from Hardy-Weinberg equilibrium. Conclusions: No associations was found between Arg194Trp and Arg280His polymorphisms with NPC risk, whereas the Arg399Gln genotype was associated with increased risk.