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.     

Polymorphisms of DNA repair gene XRCC1 and risk of glioma: a case-control study in Southern China

Objective: This study aimed to examine associations between polymorphisms in the X-ray cross-complementing group 1 (XRCC 1) gene and risk of glioma in a Chinese population. Methods: We performed a hospital-based case-control study with 271 cases and 289 controls in Guangdong province, China. Cases were patients newly diagnosed with pathologically confirmed glioma in two hospitals between June 2006 and May 2010. Controls were individuals without cancer, frequency matched by sex and age. Three SNPs in XRCC1 gene, Arg399Gln (rs25487), Arg194Trp (rs1799782) and Arg280His (rs25489), were analyzed by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) based method. Unconditional logistic regression was used to estimate the odds ratios (ORs) of polymorphisms in XRCC1 gene for glioma. Results: The Arg399Gln polymorphism was significantly associated with risk of glioma. Individuals with the Gln/Gln genotype had a significantly increased likelihood of developing glioma compared with those with the Arg/Arg genotype (adjusted OR = 1.93, 95% CI: 1.04 - 3.58), especially among males and individuals aged 50 years or older. Conclusion: The XRCC1 Arg399Gln polymorphism may be a useful susceptibility biomarker for glioma. Further studies in Chinese populations with larger sample sizes are now warranted.     

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.     

人类XRCC1-399单核苷酸多态性对原发性肝癌的影响

目的探讨人类DNA修复基因XRCC1-399单核苷酸多态性(SNP)在HBV感染者发生原发性肝细胞癌(HCC)中的作用.方法 72例HCC患者经病理检查证实,根据地缘、性别、年龄按1∶1～2比例匹配,选择137例对照者.采用聚合酶链反应-限制片段长度多态性(PCR-RFLP)技术检测受试者XRCC1基因第-399位SNP.结果单一人类XRCC1-399SNP因素与HCC的发生无关.在XRCC1-399 Arg/Arg型受试者中,HBV感染与否与HCC的发生无关(P=0.270),但在Gln/Gln型和Arg/Gln型受试者中,伴HBV感染者较不伴HBV感染者更容易发生HCC[25.7%对5.3%,Mantel-Haenszel OR估计值为2.563,95%可信区间(CI)为1.190～5.518,P=0.016].结论人类XRCC1-399位氨基酸突变在HBV阳性人群的HCC的发生中可能具有一定作用.     

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.     

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。     

Polymorphisms in DNA repair gene XRCC1 and increased genetic susceptibility to glioma

Background: The XRCC1 gene encodes the XRCC1 protein, which complexes with three other DNA repair enzymes involved in the base-excision repair (BER) pathways. Different XRCC1 polymorphisms may increase the risk of cancers by impairing interaction with other enzymatic proteins and consequently altering DNA repair activity, and result in carcinogenesis. Our study aimed to investigate any association between three polymorphisms of the XRCC1 gene at codon 194, 280 and 399 and potential glioma risk. Methods: We collected 127 patients with primary glioma and 249 controls who requested general health examinations from Union Hospital of Tongji Medical College hospital from March 2007 to September 2010. A total of 5 ml venous blood was drawn from each subject. The polymorphisms of XRCC1 gene at codons 194, 280 and 399 were analyzed based on duplex polymerase-chain-reactions with the confronting-two-pair primer (PCR-CTPP) method. Results: The homozygous Trp/Trp and heterozygotes Arg/Trp variants of codon 194 had a 2.12 fold and 1.46 fold increased risk of glioma compared to the homozygous Arg/Arg wide genotypes. The same effect was found in codon 399, the codon 399 Gln/Gln and Arg/Gln genotypes being associated with a 2.24 fold and 1.67 fold increased risk in glioma. When comparing the codon 194 Arg/Arg and 399 Arg/Arg genotypes, the combination of codon 194 Trp allele and 399 Gln allele had a heavy increase in glioma risk (OR=2.87, 95%CI=1.56-6.73). Conclusion: The present study provided evidence of a potential role for XRCC1 codon 194 and 399 polymorphisms in genetic predisposition to glioma among the Chinese population. This analysis of correlation of DNA repair genes and glioma may provide a deeper insight into the genetic and environment factors for cancer risk.     

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.     

XRCC1多态性与非吸烟女性肺腺癌易感性的关系

背景与目的XRCC1是一种DNA损伤修复基因，其单核苷酸多态性异常是导致DNA修复能力个体差异的重要原因，可能导致个体患肺癌的危险升高。本研究的目的是探讨XRCC1单核苷酸多态性与非吸烟女性肺腺癌易感性的关系。方法采用以医院患者为基础的病例对照研究方法，研究对象包括非吸烟女性肺腺癌患者126例和同期其它肺部疾病对照126例。以聚合酶链反应一限制性片段长度多态性方法分析XRCC1基因Arg399Gln多态性，比较不同基因型与非吸烟女性肺腺癌的关系，并探讨油烟暴露与基因多态交互作用对患癌风险的影响。结果与携带399Arg／Arg基因型者比较，携带399Gln／Gln基因型者患肺腺癌的风险是其8．695倍（95％CI为3．343～22．614）。携带等位基因399Gln又有油烟暴露的个体患肺腺癌的风险明显增高，校正的比值比为5．21（95％CI为1．85～14．70，P〈0．001）。结论XRCC1基因Arg399 Gln多态性可能是非吸烟女性肺腺癌的遗传易感因素。     

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…     

Predictive value of XRCC1 and XRCC3 gene polymorphisms for risk of ovarian cancer death after chemotherapy

Objective: To investigate any association between XRCC1 and XRCC3 polymorphisms and outcome ofplatinum-based chemotherapy in ovarian cancer patients. Methods: With a prospective study design was caseswere consecutively collected from January 2005 to January 2007. All 310 included patients were followed-upuntil the end of January 2010. Genotyping of XRCC1 and XRCC3 polymorphisms was conducted by TaqManGene Expression assays. Results: A total of 191 patients died during follow-up. Our study showed a lowersurvival rate in XRCC1 399 Arg/Arg genotype than Gln/ Gln, with a significant increased risk of death (HR=1.69,95%CI=1.07-2.78). Similarly, those carrying XRCC3 Thr/ Thr genotype had a increased risk as compare tothe Met/Met genotype, with a HR (95% CI) of 1.90 (1.12-3.41). There was no significant association betweenXRCC1 Arg194Trp and XRCC1Arg280His gene polymorphisms and ovarian cancer death. Conclusion: Ourstudy demonstrates that polymorphisms in DNA repair genes have roles in the susceptibility and survival ofovarian cancer patients.     

DNA repair gene XRCC3 Thr241Met polymorphism and hepatocellular carcinoma risk

The DNA repair genes have been indicated as candidates in the risk of hepatocellular carcinoma (HCC). Published data on the association between X-ray repair cross-complementing group 3 (XRCC3), a critical member of the DNA repair genes, and HCC risk were contradictory. The aim of this meta-analysis was to assess the effect of XRCC3 Thr241Met polymorphism on HCC risk by pooling available data from published case–control studies. We calculated the pooled odds ratio (OR) with the corresponding 95 % confidence interval (95 % CI) to estimate the effect. Based on the inclusion criteria, six individual studies with 2,288 cases and 3,170 controls were included into our study. Overall, significant association between the XRCC3 Thr241Met variant and HCC risk was observed under the following contrast models (OR_{Met vs. Thr}?=?1.68, 95 %CI 1.08–2.62; OR_{MetMet vs. ThrThr}?=?5.54, 95 %CI 3.09–9.94; OR_{MetMet vs. ThrThr?+?ThrMet}?=?5.70, 95 % CI 4.24–7.64). Besides, the pooled ORs indicated that the XRCC3 Thr241Met polymorphism exerted risk effect on the HCC pathogenesis among Asians. Additionally, when stratifying by the status of smoking and hepatitis B virus infection, the XRCC3 Thr241Met variant was significantly associated with HCC risk among the HBsAg (+) individuals but not the HBsAg (?) individuals, smokers, and non-smokers. The present meta-analysis suggests that the XRCC3 Thr241Met polymorphism is an independent risk factor for HCC, particularly among Asians and the HBsAg (+) individuals.     

Genetic polymorphisms of DNA repair genes XRCC1 and XRCC3 and risk of colorectal cancer in Chinese population

Aim: The distribution of DNA repair gene XRCC1 and XRCC3 genotypes was used to assess the potential influence of genetic polymorphisms on risk of colorectal cancer, and interactions with other factors. Methods: a 1:2 matched case-control study was conducted with 485 cases and 970 controls. XRCC1 and XRCC2 genotype polymorphisms were based upon duplex polymerase-chain-reaction with the confronting-two-pairprimer (PCR-CTPP) method. Results:The XRCC1 399Cln allele polymorphism was found to be associated with an increased colorectal cancer risk, while an non-significant inversely association was noted for XRCC3 241Thr/Thr genotype. We also found that individuals with the XRCC1 399 Gln and XRCC3 241Met alleles had an elevated risk, while XRCC3241Thr/Thr was proctective. Conclusion: This study is the first to provide evidence of importance of XRCC1 and XRCC3 gene polymorphisms for risk of colorectal cancer in the Chinese population.     

XRCC1和XRCC2的基因多态性在乳腺癌治疗中的临床意义

目的:乳腺癌是女性常见的恶性肿瘤之一,其发生发展与遗传因素十分密切,寻找与乳腺癌发生、病理、治疗及预后相关的分子标志物对于该病的治疗具有重要的指导意义。XRCC是参与DNA损伤修复的重要基因。XRCC1及XRCC2基因的多态性已被研究与多种肿瘤易感性及生物学行为有关。本实验研究XRCC1 和XRCC2 多态性与中国女性乳腺癌发病风险、临床病理（腋窝淋巴结转移状态）及预后(复发和转移)的相关性,以探讨其在乳腺癌临床治疗中的潜在价值。方法:采用PCR-RFLP方法检测60例原发性乳腺癌患者新鲜血标本中XRCC1 Arg399Gln、XRCC2 C41657T、XRCC2 G4234C多态,采用SAS 9.1.3统计软件分析基因型与乳腺癌发病风险、临床病理及预后的相关性。结果:XRCC1 Arg399Gln 不同基因型与乳腺癌的发病风险不存在统计学相关性(P>0.05); XRCC1 Arg399Gln与乳腺癌的腋窝淋巴结转移情况及乳腺癌的远处转移、局部复发不存在相关性(P>0.05);XRCC2 C41657T、XRCC2 G4234C 基因型与乳腺癌的发病风险均无显著相关(P>0.05);XRCC2 C41657T C/T和T/T基因型的多态性可能与乳腺癌的腋窝淋巴结转移状态、乳腺癌的远处转移及局部复发具有相关性(P<0.05)。结论:XRCC1 Arg399Gln G/G、XRCC2 C41657T、XRCC2 G4234C 基因型可能均与乳腺癌的发病风险无关。XRCC2 C41657T C/T和T/T基因型的多态性可能与乳腺癌的腋窝淋巴结转移状态、乳腺癌的远处转移及局部复发具有相关性。     

DNA修复基因ADPRT和XRCC1遗传变异与胃癌发病风险

背景与目的：DNA修复缺陷是肿瘤的遗传易感因素。二磷酸腺苷核糖转移酶（adenosine diphosphate ribosyl transferase,ADPRT）和X线修复交叉互补蛋白1（X-ray repair cross—complementing 1,XRCC1）是碱基切除修复的重要成分。这两个修复蛋白基因均存在功能性遗传。本研究探讨ADPRT 762val→Ala和XRCC1 399Arg→GIn变异单独或联合与胃癌发生风险的关系。方法：以聚合酶链反应．限制性片段长度多态分析方法,检测236例胃癌患者和708例无肿瘤正常对照的基因型。以logistic多因素回归模型计算各基因型的胃癌风险以及基因一基因交互作用对胃癌风险的影响。结果：ADPRT Ala／Ala基因型患胃癌的风险比ADPRT Val／Val基因型高2倍（OR=2．07;95％CI=1．33～3．21;P=0．001）。XRCC1 399Arg—GIn变异单独与胃癌风险无关,但与ADPRT基因型存在基因-基因交互作用,携带ADPRT Ala／Ala和XRCC1 GIn／GIn基因型者患胃癌的风险比携带ADPRT Val／Val和XRCC1 Arg／Arg者高5．32倍（95％CI=1．12～28．57;P〈0．001）。结论：ADPRT 762Val→Ala变异是胃癌的遗传易感因素,而XRCC1 399 Arg→GIn变异有促进ADPRT762 Val→Ala的作用。     

Polymorphisms of the XRCC1 DNA repair gene in head and neck cancer

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.     

DNA repair gene hOGG1 codon 326 and XRCC1 codon 399 polymorphisms and bladder cancer risk in a Japanese population

Background: Bladder cancer is the most common urologic malignancy in theUSA. Tobacco smoking generates oxidative DNA damage and inducesbladder cancer. Base excision repair (BER) is a very importantmechanism for repairing oxidative DNA damage. There are manyenzymes involved in BER. Human oxoguanine glycosylase 1 (hOGG1)and X-ray repair cross-complementing 1 (XRCC1) are enzyme genesof BER. Actually, the hOGG1 codon 326 polymorphism was associatedwith the risk of lung oesophagus and stomach cancer. On theother hand, among several XRCC1 gene polymorphisms, codon 399polymorphism was reported to reduce the risk of bladder cancerand raise the risk of lung cancer. Methods: We examined the association between the genetic polymorphismsof hOGG1 codon 326 and XRCC1 codon 399 and bladder cancer risk.In this study, we recruited 251 bladder cancer cases and 251healthy controls to evaluate the effect of hOGG1 codon 326 andXRCC1 codon 399 polymorphisms on bladder cancer. We detectedgenotypes by the polymerase chain reaction–restrictionfragment length polymorphism (PCR–RFLP) method. Results: The frequencies of the hOGG1 codon 326 genotypes Cys/Cys wassignificantly higher in the cases than in the controls. Adjustedodds ratio (OR) was 1.85 (95% CI: 1.12–3.03; p = 0.02)compared with Ser/Ser, and was 2.05 (95% CI: 1.36–3.08;p = 0.01) compared with Ser/Ser + Ser/Cys. In addition, whenevaluated with smoking status, the adjusted OR (Cys/Cys versusSer/Ser + Ser/Cys) ran up to 2.78 (95% CI: 1.39–5.60;p < 0.01) among non-smokers. For the XRCC1 polymorphism,the Gln/Gln of XRCC1 codon 399 genotype was statistically higherin the controls than in the cases though compared with Alg/Alg+ Alg/Gln. The adjusted OR was 0.45 (95% CI: 0.21–0.99;p = 0.05), and was lifted up to 0.37 (95% CI: 0.14–0.98;p = 0.05) among smokers. Conclusion: It is indicated that the hOGG1 codon 326 and XRCC1 codon 399polymorphisms are risk factors of bladder cancer.     

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.     

XRCC1 R399Q基因多态性与结直肠癌易感性的Meta分析

目的探讨X—rayrepair cross—complementing group1（XRCC1）RB99Q基因多态性与结直肠癌易感性的关系。方法通过计算机检索和手工检索,收集有关XRCC1 R399Q基因多态性与结直肠癌易感性关系的文献,筛选出符合条件的文献,应用Meta分析软件对各项研究进行异质性检验,计算合并OR值及其95％可信区间,并行敏感性分析和发表偏倚的评估。结果国内外共有21篇文献纳入研究（结直肠癌组6229例;对照组10692例）。Meta分析结果显示：XRCC1 R399Q基因多态性在整个人群中与结直肠癌无明显的关联性（OR QQvs、RR=1．10,95％CI=0．90～1．35;OR QQ/RQvs.RR=1．02,95％CI=0．90～1．16;OR QQvs.RR/RQ=1．12,95％CI=0．95～1．33）。通过种族的分层分析发现XRCC1 R399Q基因多态性与结直肠癌易感性在亚洲人群和欧洲人群中无差异。结论XRCC1 R399Q基因多态性与结直肠癌间不存在明显的易感性。