XRCC1 Arg399Gln gene polymorphism and hepatocellular carcinoma risk in the Chinese Han population: a meta-analysis

The X-ray Repair Cross-Complementing Group 1 Arg399Gln Genetic Polymorphism and Risk of Hepatocellular Carcinoma in an Iranian Population

BACKGROUND

The association between X-ray repair cross-complementing group 1 (XRCC1) Arg399Gln gene polymorphism and hepatocellular carcinoma (HCC) has been investigated in several populations. However, the findings are controversial. The aim of this study was to address the association between XRCC1 Arg399Gln polymorphism and HCC in an Iranian population.

METHODS

We have evaluated the association between XRCC1 Arg399Gln gene polymorphism and HCC in 151 Iranian individuals (50 patients with HCC and 101 healthy matched controls) using polymerase chain reaction-restriction fragment length polymorphisms (PCR-RFLP) method.

RESULTS

Significant association was found for the XRCC1 A allele and HCC [OR = 1.93, 95% CI (1.16 - 3.25), P = 0.0099]. Also, genotype analysis by SNPStats online software showed a significant association between XRCC1 gene polymorphisms and HCC under co-dominant, dominant, and recessive genetic models.

CONCLUSION

Our study provides evidence that the XRCC1 Arg399Gln polymorphism may be associated with the risk of HCC development in Iranian population.

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 group 1 (XRCC1) Arg399Gln polymorphism and lung cancer risk in Chinese population. However, the epidemiological results remained controversial. The objective of this study was to clarify the association of XRCC1 Arg399Gln polymorphism with lung cancer risk in the Chinese population.

MATERIALS AND METHODS

Systematic searches were performed through the database of Medline/Pubmed, Web of Science, Embase, CNKI and WanFang Medical Online. Odds ratios (ORs) with 95% confidence interval (95%CI) were calculated to estimate the strength of the association.

RESULTS

Overall, we observed an increased lung cancer risk among subjects carrying XRCC1 codon 399 Gln/Gln genotype (OR=1.36, 95%CI: 1.09-1.71) in the Chinese population on the basis of 19 studies with 5,416 cases and 5,782 controls. We did not observe any association between XRCC1 codon 399 Arg/Gln and Arg/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 risk among subjects carrying XRCC1 codon 399 Arg/Gln+Gln/Gln genotype on the basis of hospitalized patient-based controls (OR=1.21, 95%CI: 1.04-1.42) and among subjects carrying XRCC1 codon 399 Gln/Gln genotype on the basis of healthy subject-based controls (OR=1.22, 95%CI: 1.04-1.43).

CONCLUSIONS

Our findings indicated that certain XRCC1 Arg399Gln variants might affect the susceptibility of lung cancer in Chinese population. Larger sample size studies are required to confirm our findings.

The XRCC1 Arg399Gln gene polymorphism and risk of colorectal cancer: a study in Kashmir

BACKGROUND

The DNA repair gene XRCC1 Arg399Gln gene polymorphism has been found to be implicated in the development of various cancers, including colorectal cancer (CRC), in different populations. We aimed to determine any association of this polymorphism with the risk of CRC in Kashmir.

MATERIALS AND METHODS

A total of 120 confirmed cases of CRC and 146 healthy cancer free controls from the Kashmiri population were included in this study. Genotyping was carried out by the polymerase chain reaction- restriction fragment length polymorphism (PCR-RFLP) method.

RESULTS

Genotype frequencies of XRCC1 Arg399Gln observed in controls were 34.2%, 42.5% and 23.3% for GG (Arg/Arg), GA (Arg/Gln), AA( Gln/Gln), respectively, and 28.3%, 66.7% and 5% in cases, with an odds ratio (OR)=5.7 and 95% confidence interval (CI) =2.3-14.1 (p=0.0001). No significant association of Arg399Gln SNP with any clinicopathological parameters of CRC was found.

CONCLUSIONS

We found the protective role of 399Gln allele against risk to the development of CRC. The XRCC1 heterozygote status appears to be a strong risk factor for CRC development in the Kashmiri population.

Genetic polymorphisms of XRCC1 gene and susceptibility to hepatocellular carcinoma in Chinese population

Hepatocellular carcinoma (HCC) is a common cancer in the worldwide. Accumulated evidences indicate that genetic polymorphisms of human X-ray repair complementing group 1 gene (XRCC1) are associated with the susceptibility to HCC. This study aims to investigate the potential association between XRCC1 c.482C>T and c.1178G>A genetic polymorphisms and the susceptibility to HCC. A total of 1,069 Chinese Han subjects consisting of 530 HCC patients and 539 cancer-free controls were recruited in this case-control study. The created restriction site-polymerase chain reaction and directly DNA sequencing methods were utilized to analyze the genotyping of XRCC1 genetic polymorphisms. Our data suggested that the XRCC1 c.482C>T and c.1178G>A genetic polymorphisms were statistically associated with the increased risks of HCC [for c.482C>T, TT vs. CC: OR 2.05, 95% CI 1.26-3.32, P = 0.003; T vs. C: OR 1.26, 95% CI 1.04-1.51, P = 0.017; for c.1178G>A, AA vs. GG: OR 2.15, 95% CI 1.26-3.67, P = 0.004; A vs. G: OR 1.33, 95% CI 1.10-1.61, P = 0.004]. The allele-T and genotype-TT of c.482C>T and allele-A and genotype-AA of c.1178G>A genetic polymorphisms may enhance the susceptibility to HCC. Our findings indicate that the studied XRCC1 genetic polymorphisms may influence the risk of HCC in Chinese populations and might be used as molecular markers for assessing the risk of HCC.

XRCC1 Arg399Gln genetic polymorphism and the risk of hepatocellular carcinoma: a meta-analysis

The X-ray repair cross-complementing group 1 (XRCC1) gene, one of over 20 genes that participate in the base excision repair pathway, is thought to account for differences in susceptibility to hepatocellular carcinoma. To assess the relationship between the XRCC1 Arg399Gln polymorphism and the risk of hepatocellular carcinoma (HCC), we performed a meta-analysis. All the relevant studies were extracted from PubMed, Embase, the Chinese biomedicine databases, the Chinese national knowledge infrastructure, and the Wanfang databases (prior to August 2012). The meta-analysis was performed using all eligible studies, which covered a total of 2,554 cases and 3,320 controls, to examine the association between XRCC1 Arg399Gln polymorphism and the risk of HCC. Our analysis suggested that the variant genotypes of the XRCC1 Arg399Gln gene were associated with a significantly increased risk of HCC in a co-dominant model (Arg/Gln vs. Arg/Arg, odd ratios [OR] 1.39, 95 % confidence interval [CI] 1.08-1.79; Gln/Gln vs. Arg/Arg, OR 1.26, 95 % CI 1.04-1.52) and a dominant model (Arg/Gln + Gln/Gln vs. Arg/Arg OR 1.36, 95 % CI 1.07-1.72), whereas no association was observed in the recessive model (Gln/Gln vs. Arg/Gln + Arg/Arg, OR 1.05, 95 % CI 0.91-1.21). The results of the subgroup analysis by ethnicity indicated that the XRCC1 Arg399Gln polymorphism was associated with increased risk of HCC in Asian populations using the co-dominant model (Arg/Gln vs. Arg/Arg, OR 1.41, 95 % CI 1.06-1.87) and the dominant model (Gln/Gln vs. Arg/Gln + Arg/Arg, OR 1.35, 95 % CI 1.03-1.76). Our analysis provides evidence that the XRCC1 Arg399Gln polymorphism may be associated with a higher risk of HCC, especially among Asian populations.

Association between the XRCC1 Arg399Gln polymorphism and risk of cancer: evidence from 297 case-control studies

BACKGROUND

The Arg399Gln polymorphism in the X-ray cross-complementing group 1 (XRCC1) had been implicated in cancer susceptibility. The previous published data on the association between XRCC1 Arg399Gln polymorphism and cancer risk remained controversial.

METHODOLOGY/PRINCIPAL FINDINGS

To derive a more precise estimation of the association between the XRCC1 Arg399Gln polymorphism and overall cancer risk, we performed a meta-analysis of 297 case-control studies, in which a total of 93,941 cases and 121,480 controls were included. Overall, significantly increased cancer risk was observed in any genetic model (dominant model: odds ration [OR] = 1.04, 95% confidence interval [CI] = 1.01-1.07; recessive model: OR = 1.08, 95% CI = 1.03-1.13; additive model: OR = 1.09, 95% CI = 1.04-1.14) when all eligible studies were pooled into the meta-analysis. In further stratified and sensitivity analyses, significantly elevated hepatocellular and breast cancers risk were observed in Asians (dominant model: OR = 1.39, 95% CI = 1.06-1.84) and in Indians (dominant model: OR = 1.64, 95% CI = 1.31-2.04; recessive model: OR = 1.94, 95% CI = 1.09-3.47; additive model: OR = 2.06, 95% CI = 1.50-2.84), respectively.

CONCLUSIONS/SIGNIFICANCE

This meta-analysis suggests the participation of XRCC1 Arg399Gln is a genetic susceptibility for hepatocellular cancer in Asians and breast cancer in Indians. Moreover, our work also points out the importance of new studies for Arg399Gln association in some cancer types, such as glioma, gastric cancer, and oral cancer, where at least some of the covariates responsible for heterogeneity could be controlled, to obtain a more conclusive understanding about the function of the XRCC1 Arg399Gln polymorphism in cancer development.

Angiotensinogen gene polymorphism and ischemic stroke in East Asians: A meta-analysis

Objective:

To investigate the association between angiotensinogen gene M235T polymorphism and ischemic stroke in East Asians.

Data Retrieval:

A computer-based online search was conducted in PubMed, Google scholar, China National Knowledge lnfrastructure database between January 1990 and April 2012 for relevant studies. The key words were angiotensinogen or AGT, polymorphism or genetic and ischemic stroke or cerebral infarction.

Selection Criteria:

Case-controlled studies addressing the correlation between angiotensinogen gene M235T polymorphism and ischemic stroke in East Asians were included. The distribution of genotypes in the included studies was tested for Hardy-Weinberg equilibrium. Quality evaluation of the included studies was conducted by two physicians. Statistical analyses were carried out using Stata 12.0 software for meta-analysis. Heterogeneity tests, sensitivity analysis and publication bias were also conducted.

Main Outcome Measures:

The association between angiotensinogen gene M235T polymorphism and ischemic stroke risk in East Asians was assessed.

Results:

Six relevant studies involving 891 patients with ischemic stroke and 727 controls were included in this meta-analysis. Results showed that there was a significant association between angiotensinogen gene M235T polymorphism and the risk of ischemic stroke in East Asians (T vs. M: odds ratio (OR) = 1.54, 95% confidence interval (CI) = 1.10–2.16; TT vs. MM: OR = 2.24, 95%CI = 1.37–3.66; TT vs. MT: OR = 1.76, 95%CI = 1.41–2.20; MM + MT vs. TT: OR = 0.57, 95%CI = 0.46–0.70). Sensitivity analysis confirmed that the study results were stable and reliable, with no publication bias.

Conclusion:

The angiotensinogen gene M235T polymorphism is associated with ischemic stroke in East Asians, and the TT genotype and T allele are risk factors for ischemic stroke.