PSCA rs2294008 C > T polymorphism contributes to gastric and bladder cancer risk

Previous studies suggested genetic variations in PSCA (prostate stem cell antigen) may confer the susceptibility of cancer. Many case-control studies have reported the relationship between PSCA rs2294008 C > T polymorphism and cancer, especially gastric cancer and bladder cancer. However, the results are inconsistent. This meta-analysis is aimed at evaluating the association of rs2294008 polymorphism with cancer risk. The databases of PubMed, ISI Web of Knowledge, EMBASE, and Chinese National Knowledge Infrastructure (CNKI) were searched for related publications. Odds ratios (ORs) and 95% confidence intervals (CIs) were used to estimate the strength of the associations. Fixed models were used when heterogeneity among studies was not detected, otherwise the random model was used. Twenty-six studies from 24 articles with 30,050 multiple cancer cases and 51,670 controls were pooled into this meta-analysis. The results showed that the rs2294008 polymorphism was associated with increased cancer risk in any genetic model (T vs C, OR: 1.18, 95% CI: 1.08-1.28; TT vs CC, OR: 1.36, 95% CI: 1.14-1.62; TC vs CC, OR: 1.29, 95% CI: 1.17-1.44; TT + TC vs CC, OR: 1.32, 95% CI: 1.18-1.49; TT vs TC + CC, OR: 1.15, 95% CI: 1.02-1.30). In stratified analysis by cancer type, we found that the T allele had a significant high risk of gastric and bladder cancer, but not in other cancers. In subgroup analysis by ethnicity, increased cancer risk was found in both Asians and Caucasians. Our study suggested that the PSCA rs2294008 C > T polymorphism is a risk factor for cancer, especially in gastric and bladder cancer.