The PSCA polymorphisms derived from genome-wide association study are associated with risk of gastric cancer: a meta-analysis

Prostate stem cell antigen (PSCA) is a glycosylphosphatidylinositol-anchored 123-aa protein related to the cell-proliferation inhibition and/or cell-death induction activity. Many studies had reported the role of PSCA rs2294008 C > T and rs2976392 G > A polymorphisms on gastric cancer risk. To investigate a more precise estimation of the relationships, we performed a meta-analysis on 9 case-control studies included 10,746 cases and 9,158 controls. Odds ratios (ORs) and 95 % confidence intervals (CIs) were used to assess the strength of the association. For PSCA rs2294008 C > T polymorphism, there was a significantly increased risk of gastric cancer in all genetic models (TT/TC vs. CC: OR = 1.61, 95 % CI = 1.35-1.91; TT vs. TC/CC: OR = 1.33, 95 % CI = 1.24-1.42). Similar results were also observed for PSCA rs2976392 G > A polymorphism (AA/AG vs. GG: OR = 1.69, 95 % CI = 1.24-2.31; AA vs. AG/GG: OR = 1.36, 95 % CI = 1.24-1.50). In the stratified analysis by ethnicity of rs2294008, an increased gastric cancer risk was found in both Asians (TT vs. TC/CC: OR = 1.31, 95 % CI = 1.22-1.42) and Europeans (TT/TC vs. CC: OR = 1.42, 95 % CI = 1.18-1.71). Furthermore, when stratified by clinicopathologic characteristics of tumor location and histology, a higher risk on non-cardia compared with cardia gastric cancer (TT vs. TC/CC: OR = 1.43, 95 % CI = 1.12-1.83) as same as diffused compared with intestinal gastric cancer (TT vs. TC/CC: OR = 1.29, 95 % CI = 1.13-1.49) was observed. These findings supported that PSCA rs2294008 C > T and rs2976392 G > A polymorphisms may contribute to the susceptibility to gastric cancer, particular in non-cardia or diffused gastric cancer.