Lycopene reduces azoxymethane-induced colon tumors in Fisher 344 rats

Epidemiologic studies have shown an inverse correlation between dietary intake of lycopene and the incidence of colon cancer. This study was conducted to determine (1) the effects of dietary lycopene (0, 200, and 400 ppm) and its interactions with fat levels (7% and 14% fat) on azoxymethane-induced colon tumors in Fisher 344 male weanling rats and (2) to the effect of dietary lycopene (400 ppm/7% fat and 400 ppm/14% fat) on tumor initiation and promotion stages in the colon. Dietary lycopene showed an effect in reducing the total number of tumors as well as tumor size in rats. Glutathione S-transferases activity was significantly higher (P < .05) in the lycopene-fed rats. This study provides evidence that dietary lycopene suppresses azoxymethane-induced colon tumors in Fisher 344 male rats at the initiation and promotion stages. Hence, the findings suggest that colon cancer may be highly sensitive to dietary intervention.