An association between XPC Lys939Gln polymorphism and the risk of bladder cancer: a meta-analysis

The polymorphism Lys939Gln in xeroderma pigmentosum complementation group C (XPC) gene has been reported to be associated with bladder cancer in some studies, though the results remain inconclusive. To explore this relationship between XPC Lys939Gln polymorphism and the susceptibility for bladder cancer and the impact of smoking exposures, a cumulative meta-analysis was performed in this study. PubMed and EMBASE databases have been systematically searched to identify relevant studies. Data were abstracted independently by two reviewers. A meta-analysis was performed to examine the association between XPC Lys939Gln polymorphism and susceptibility to bladder cancer (BC). Odds ratios (ORs) and 95 % confidence intervals (CIs) were calculated. Thirteen studies were chosen in this meta-analysis, involving 4,927 BC cases (1,119 Asian, 2,670 Caucasian, and 1,138 mixed) and 5,185 controls (1,399 Asian, 2,629 Caucasian, and 1,157 mixed). The XPC 939Gln allele was significantly associated with increased risk of BC based on allelic contrast (OR = 1.11, 95 % CI = 1.02-1.21), homozygote comparison (OR = 1.35, 95 % CI = 1.08-1.68), and a recessive genetic model (OR = 1.36, 95 % CI = 1.09-1.68). The results from the present meta-analysis indicated that the 939Gln polymorphism in XPC is a risk factor for bladder carcinogenesis. Further large and well-designed studies are needed to confirm this conclusion.