ABSTRACT
PURPOSE: This study was performed to investigate the interaction of genetic polymorphisms of glutathione S-transferases and L-myc proto-oncogene with smoking, drinking, and dietary factors in the carcinogenesis of gastric cancer. MATERIALS AND METHODS: Two hundred and four gastric cancer patients and 1:1 matched hospital controls were the study subjects. They were interviewed with a questionnaire including alcohol consumption, smoking and dietary habit. We investigated genetic polymorphisms of GSTM1, GSTT1 and L-myc genes using PCR-RFLP techniques. RESULTS: Smoking and soybean paste stew were risk factors and doughnut, fried potato, welsh onion, rice cake, seaweed, slices of raw fish, melon, tomato, garlic and onion were protective factors of gastric cancer. The odds ratios of some food items changed significantly according to the genotypes; green vegetables and pork according to the GSTM1 genotype; pork, soybean curd, steamed or hard-boiled soybean and welsh onion according to the GSTT1 genotype; rice cake and garlic according to the L-myc proto-oncogene genotype. CONCLUSION: These results suggest that the genetic polymorphisms of GSTM1, GSTT1 and L-myc genes might modify the effects of environmental factors on gastric cancer possibly by engaging in the metabolism of food, alcohol and cigarette smoke.