XRCC1 Arg194Trp polymorphism is associated with oral cancer risk: evidence from a meta-analysis.

Previous studies show that X-ray cross-complementing group 1 (XRCC1) Arg194Trp may result in variations in host's repair efficiency of DNA damage, and this repair deficit may eventually cause individual susceptibility to oral cancer. However, published data regarding the association between XRCC1 Arg194Trp polymorphism and oral cancer risk were contradictory. The aim of this study was to derive a more precise estimation of the association of XRCC1 Arg194Trp polymorphism with oral cancer by performing a meta-analysis. Odds ratios (ORs) and 95 % confidence intervals (95 % CIs) were used to assess the strength of the association. Finally, a meta-analysis of nine eligible studies including 1,281 cases and 1,966 controls was performed. Overall, there was a significant association between XRCC1 Arg194Trp polymorphism and oral cancer risk (for Trp versus Arg: OR = 1.41, 95 % CI 1.08-1.83, P = 0.01; for TrpTrp versus ArgArg: OR = 1.50, 95 % CI 1.00-2.30, P = 0.05; for TrpTrp/ArgTrp versus ArgArg: OR = 1.49, 95 % CI 1.14-1.94, P = 0.003). After excluding those studies containing patients with oral leukoplakia, there was still an obvious association between XRCC1 Arg194Trp polymorphism and oral cancer risk (for TrpTrp/ArgTrp versus ArgArg: OR = 1.40, 95 % CI 1.14-1.71, P = 0.001). Subgroup analysis by ethnicity suggested that there was an obvious association between XRCC1 Arg194Trp polymorphism and oral cancer risk in Asians under three genetic models. In conclusion, the results from this meta-analysis suggest that XRCC1 Arg194Trp polymorphism is associated with oral cancer risk, especially in Asians.