INHIBITORY EFFECTS OF REBAMIPIDE ON ENNG-INDUCED DUODENAL CARCINOGENESIS IN MICE - A POSSIBLE STRATEGY FOR CHEMOPREVENTION OF GASTROINTESTINAL CANCERS

Rebamipide is a potent antioxidative agent; it increases gastric mucos al PGE, production and thus protects the gastric mucosa. We hypothesiz ed that the mechanisms of ulcer formation could be extended to carcino genesis and that an increase in gastric mucosal protection may result in a decrease in gastric carcinogenesis. Therefore, we assessed the in hibitory effects of rebamipide on N-ethyl-N' -nitro-N-nitrosoguanidine (ENNG) -induced carcinogenesis in mice. The percentage of tumor-beari ng mice in three treatment groups-ENNG + rebamipide 20 mg, ENNG + reba mipide 50 mg, and ENNG alone-was 55%, 42%, and 67%, respectively. The incidence of tumorigenesis tended to decrease with increasing doses of rebamipide. The difference between ENNG + rebamipide 50 mg and ENNG a lone was statistically significant (P < 0.05). These results suggest t hat rebamipide may strengthen the host defense mechanisms related to c arcinogenesis in the digestive tract.