Current evidence on XPC rs2228001 A/C polymorphism and bladder cancer susceptibility

The xeroderma pigmentosum group C (XPC) gene plays a significant role in DNA damage recognition during nucleotide excision repair process. Polymorphisms of the XPC gene have been analyzed in numerous casecontrol studies to evaluate bladder cancer risk attributed to XPC genetic variation; however, published data on the association between XPC rs2228001 A/C and bladder cancer risk are inconclusive. To assess the impact of XPC rs2228001 polymorphism on bladder cancer risk, we performed a meta-analysis on all available studies including 4,741 patients and 5,065 control subjects. The overall results indicated a positive association of the variant on bladder cancer risk using an allelic contrast, homozygote comparison and the recessive genetic model. When stratified by ethnicity, obvious associations were found in Asian descendants by using an allelic contrast (odds ratio [OR] = 1.33, 95% confidence interval [CI] = 1.06-1.66, Pheterogeneity = 0.002), homozygote comparison (OR = 1.91, 95% CI = 1.30-2.82, Pheterogeneity = 0.040) and the recessive genetic model (OR = 1.64, 95% CI = 1.25-2.15, Pheterogeneity = 0.128). Furthermore, a significant association was found in smokers by using an allelic contrast (OR = 2.08, 95% CI = 1.044.17, Pheterogeneity = 0.039), homozygote comparison (OR = 4.66, 95% CI = 1.22-17.76, Pheterogeneity = 0.024) and the recessive genetic model (OR = 3.79, 95% CI = 1.18-12.20, Pheterogeneity = 0.027). In conclusion, XPC rs2228001 A/C polymorphism may contribute to the risk for developing bladder cancer in Asian descendants and may interact with smoking exposure. Further studies based on larger, more diverse case-control populations are warranted to further evaluate the association.