Poly (AT) deletion/insertion polymorphism of the XPC gene contributes to urinary system cancer susceptibility: a meta-analysis.

Numerous studies have investigated the association between xeroderma pigmentosum complementation group C (XPC) poly (AT) deletion/insertion (PAT -/+) polymorphism and cancer susceptibility; however, the findings are inconsistent. Therefore, we performed a meta-analysis based on 32 publications including 10,214 cases and 11,302 controls to acquire a more robust estimation of the relationship. We searched publications from MEDLINE, EMBASE and CBM which assessed the associations between XPC PAT -/+ polymorphism and cancer risk. We calculated pooled odds ratio (OR) and 95% confidence interval (CI) by using either fixed-effects or random-effects model. We found that individuals carrying the PAT +/+ genotype have significantly increased cancer risk (PAT +/+ vs. PAT -/-: OR=1.18, 95% CI=1.03-1.35 and recessive model: OR=1.19, 95% CI=1.06-1.33). Further stratification analysis showed a significantly increased risk for prostate cancer (PAT +/+ vs. PAT -/-: OR=2.20, 95% CI=1.39-3.48, recessive model: OR=2.07, 95% CI=1.33-3.23 and PAT + vs. PAT -: OR=1.39, 95% CI=1.12-1.71), bladder cancer (recessive model: OR=1.33, 95% CI=1.03-1.72), Caucasian ethnicity (recessive model: OR=1.21, 95% CI=1.02-1.43), population-based studies (recessive model: OR=1.23, 95% CI=1.05-1.43) and studies with relatively large sample size (PAT +/+ vs. PAT -/-: OR=1.18, 95% CI=1.04-1.35 and recessive model: OR=1.20, 95% CI=1.08-1.33). Despite some limitations, this meta-analysis established solid statistical evidence for the association between the XPC PAT +/+ genotype and cancer risk, especially for urinary system cancer, but this association warrants further validation in single large studies.