HLA genotype and development of gastric cancer in patients with Helicobacter pylori infection

BACKGROUND/AIMS: Helicobacter pylori (HP) infection is reported to be involved in gastric carcinogenesis. However, only a small percentage of HP-infected patients actually develop gastric cancer. In the present study, we assessed HLA antigen polymorphism and investigated its relationship with the development of gastric epithelial tumors in patients who had HP infection. METHODOLOGY: Among patients with serologically proven HP infection, 80 cases who underwent endoscopic mucosectomy for gastric epithelial tumors (24 adenomas and 56 carcinomas) were recruited in the study (the tumor group), and 20 cases without tumors were also included as controls (the nontumor group). HLA status (HLA-A, HLA-B, HLA-DRB1 and HLA-DQB1) was determined by HLA-DNA typing. RESULTS: HLA-B*05401, HLA-DQB1*0601 and HLA-DRB1*1502 genes showed a significantly higher frequency in the control group than in the tumor group (0.225 vs. 0.088, P=0.015; 0.3 vs. 0.163, P = 0.047; 0.175 vs. 0.069, P = 0.036, respectively). CONCLUSIONS: It suggests that HLA-B*5401, HLA-DQB1*0601 and HLA-DRB1*1502 may contribute to the inhibition of gastric carcinogenesis. Thus, HP-infected patients without these genotypes should undergo HP eradication therapy and close follow-up.