Effect of chronic smoking on lipid peroxidation and antioxidant status in gastric carcinoma patients.

Oxidative stress plays an important role in malignant transformation and is postulated to be associated with increased lipid peroxidation. We determined the effects of chronic cigarette smoking on lipid peroxidation and antioxidant status in 100 male patients with gastric cancer and an equal number of age-matched healthy control subjects. The mean (SD) level of thiobarbituric acid reactive substances (TBARS) was higher in plasma (healthy non-smokers 3.1 [0.2]; healthy smokers 4.6 [0.2]; gastric cancer non-smokers 6.5 [1.0]; gastric cancer smokers 8.9 [3.1]) and erythrocytes (3.3 [0.6]; 4.6 [0.1]; 8.3 [0.9]; 13.2 [5.1]) from gastric cancer patients when compared with control subjects. TBARS level was higher in smokers than non-smoking gastric cancer patients. The activities of superoxide dismutase, catalase, glutathione peroxidase, glutathione-S-treansferase, reduced glutathione, and vitamins A, E and C were decreased in gastric cancer patients who were smokers as compared to other groups (p<0.001). Thus, there occurs lipid peroxidation and possible breakdown of antioxidant status in cigarette smoking, which may increase the risk of gastric cancer.