Effects of PSCA Rs2294008 (C/T) and C-MYC Rs9642880 (G/T) Polymorphisms on Bladder Cancer: Evidence from a Meta-analysis

Previous studies have investigated the associations between the two polymorphisms (prostate stem cell antigen (PSCA) rs2294008 C/T and c-MYC rs9642880 G/T) and bladder cancer (BC) risk. However, the results are inconsistent. We therefore carried out a meta-analysis to estimate the relationship between PSCA/c-MYC polymorphisms and BC risk. We searched PubMed up to November 2014 to identify potentially eligible literatures. Odds ratios (ORs) and 95% confidence intervals (CIs) were used to estimate the strength of the associations, the data were further stratified by ethnicity. Heterogeneity was evaluated by Q test and I(2) statistics. Begg's funnel plot and Egger's test were used to assess the publication bias. 11 studies from 9 articles were identified, including a total of 16,814 cancer cases and 52,868 case-free controls. We found a significant association between PSCA rs2294008 polymorphism and BC risk (the allele contrast model: OR = 1.14, 95% CI = 1.11-1.18; homozygote comparison: OR = 1.28, 95% CI = 1.20-1.37; heterozygote comparison: OR = 1.23, 95% CI = 1.17-1.30; dominant model: OR = 1.25, 95% CI = 1.19-1.31 and recessive model: OR = 1.13, 95% CI = 1.07-1.20). Moreover, a significant increased risk of BC was confirmed both in Caucasian and in Asians. For c-MYC rs9642880 polymorphism, significant increased BC risk was detected under the following genetic models (the allele contrast model: OR = 1.20, 95% CI = 1.13-1.27; homozygote comparison: OR = 1.37, 95% CI = 1.21-1.55; heterozygote comparison: OR = 1.20, 95% CI = 1.09-1.32; dominant model: OR = 1.25, 95% CI = 1.14-1.37 and recessive model: OR = 1.26, 95% CI = 1.13-1.40). Further stratified analysis by ethnicity also observed the same results. This meta-analysis suggested that PSCA rs2294008 and c-MYC rs9642880 polymorphisms may increase the BC risk. Further studies are needed to clarify the effects.