Abstract: AIM: To investigate the preventive and therapeutic effects of kwoninone on experimental hepatocellular carcinoma induced by 2-AAF and the mechanisms of its effects on cell proliferation.METHODS: Animal model of hepatocellular carcinoma was established by feeding SD rats with 0.05 % 2-AAF.Different doses of kwoninone were injected intraabdominally to observe the effects on occurrence of cancerous nodules.The expression of PCNA was observed by immunohistochemistry. The expression of cyclin D1 and CDK4 were detected by RT-PCR method.RESULTS: The cancerous nodules in preventive and therapeutic groups were significantly lower than that in model group and the cancerous nodules of preventive group were the lowest.The expression of cyclin D1 and CDK4 in preventive and therapeutic groups were significantly lower than that in model groups (P <0.01). CONCLUSION: Kwoninone can prevent or postpone hepatocarcinogenisis of hepatocellular carcinoma induced by 2-AAF.Kwoninone inhibits proliferation of liver cancer cells by inhibiting the expression of PCNA, cyclin D1 and CDK4 and inducing cell cycle arrest.

Key words: kwoninone, 2-AAF, hepatocellular carcinoma, PCNA, cyclin D1, CDK4