Association and haplotype analysis of prostate stem cell antigen with gastric cancer in Tibetans.

Genetic factors are known to be important in the development of gastric cancer (GC). Prostate stem cell antigen (PSCA) has been shown to be expressed in diffuse-type GC, and PSCA variation is associated with susceptibility to diffuse-type GC in Japanese and Korean populations. The aim of this study was to investigate the association between PSCA gene polymorphisms and GC in a Tibetan population. We analyzed single-nucleotide polymorphisms of the PSCA gene in 196 patients with GC and 246 controls in a Tibetan population, using a polymerase chain reaction/ligase detection reaction test. The rs2294008 C/T polymorphism of the PSCA gene was significantly associated with the susceptibility to GC. The CT genotype was associated with a significantly higher risk of GC when compared with the CC genotype (odds ratio [OR] = 1.50; 95% confidence interval [CI], 1.01-2.23). Patients carrying the T allele had a significantly higher risk for developing GC compared with individuals carrying the C allele (OR = 1.34; 95% CI, 1.00-1.79). Haplotype analyses showed that CA haplotype was associated with a significantly decreased risk of GC when compared with the CG haplotype (OR = 0.47; 95% CI, 0.24-0.93). Our data indicate that PSCA gene polymorphisms may be associated with GC in Tibetans.