Family history and gastric carcinoma: The role of glutathione peroxidase

Background: The risk of gastric carcinoma is increased in persons with a positive family history of the disease. Previous findings suggest that free radicals are involved in both the initiation and promotion of carcinogenesis. Objective: The aim of this study was to assess whether alterations in the antioxidant defense system of gastric mucosal cells in patients with gastric carcinoma are related to a positive family history. Methods: Glutathione peroxidase activity, oxidized glutathione, total glutathione, and malondialdehyde levels were assayed in patients with gastric carcinoma with and without a family history of the disease. A control group consisted of healthy volunteers. Results: The study enrolled 65 patients with gastric carcinoma: 35 with and 30 without a family history of the disease, as well as 30 control subjects. The level of glutathione peroxidase activity in tumor-free tissue samples from patients with a family history of gastric carcinoma was higher than in samples from those without such family history. Glutathione peroxidase activity was also significantly higher in neoplastic than in tumor-free tissue. There was no significant difference in glutathione peroxidase activity between neoplastic tissue samples taken from patients with and without a positive family history. Conclusions: The results appear to support the existence of an enzymatic imbalance caused by cellular initiation in patients with a family history of gastric carcinoma. This imbalance may lead to an altered response to free radical oxygen species and a consequent progressive increase in biologic damage.