Genetic variation in PSCA and bladder cancer susceptibility in a Chinese population

Recently, two genome-wide association studies identified a significant association between the prostate stem cell antigen (PSCA) rs2294008 (C > T) polymorphism and risk of diffuse-type of gastric cancer in Asians and bladder cancer in Caucasians, respectively. PSCA has been reported highly expressed in bladder cancer and been considered as a useful marker for diagnosis and progression of bladder cancer. To determine whether rs2294008 polymorphism is associated with risk of bladder cancer in Chinese populations, we conducted a hospital-based case-control study of 581 cases and 580 controls. Sixteen normal bladder tissues adjacent to tumors were used to evaluate the functionality of this polymorphism. We genotyped the rs2294008 polymorphism and assessed its association with risk of bladder cancer and messenger RNA (mRNA) expression in normal bladder tissues. A significant increased risk of bladder cancer was found for rs2294008 CT/TT genotypes (adjusted odds ratio, 1.38; 95% confidence interval, 1.09-1.75) compared with the CC genotype. Furthermore, analysis of PSCA mRNA expression identified a clear correlation of rs2294008 with expression levels of PSCA mRNA. These results indicated that the rs2294008 polymorphism of PSCA gene may play a role in bladder cancer carcinogenesis and it could be served as a biomarker for genetic susceptibility to bladder cancer in Chinese populations.