Antitumor agents 220. Antitumor-promoting effects of cimigenol and related compounds on Epstein-Barr virus activation and two-stage mouse skin carcinogenesis.

Abstract Cimigenol ( 1 ) and 39 related compounds were screened as potential antitumor promoters by examining the ability of the compounds to inhibit Epstein–Barr virus early antigen (EBV-EA) activation (induced by 12- O -tetradecanoylphorbol-13-acetate) in Raji cells. Structure–activity relationship analysis indicated that compound 1 showed the highest activity and also exhibited significant inhibitory effects on mouse skin tumor promotion in an in vivo two-stage carcinogenesis test. These data suggest that 1 and the related compounds might be valuable anti-tumor promoters.