Cancer chemopreventive agents, serratane-type triterpenoids from Picea jezoensis

Seven serratane-type triterpenoids isolated from the cuticle of Picea jezoensis (Sieb. et Zucc.) Carr. jezoensis (Pinaceae) and the stein bark of Picea jezoensis (Sieb. et Zucc.) Carr. hondoensis (Mayer) Rehder (Pinaceae) were studied their possible inhibitory effects on Epstein-Barr virus early antigen (EBV-EA) activation induced by 12-O-tetradecanoylphorbol-13-acetate (TPA). All compounds showed strong inhibitory effects on the EBV-EA activation, being stronger than that of oleanolic acid, which exerts on cancer preventive activity in animal carcinogenesis models. Among these compounds, 13 alpha, 14 alpha -epoxy-3 beta -methoxyserratan-21 beta P-ol and 3 beta -methoxy-21 alpha -hydroxyscrrat-14-en-29-al were investigated for the inhibitory effects in a two-stage mouse skin carcinogenesis test on mouse skin using 7,12-dimethylbenz[a]anthracene as initiator and TPA as promoter. 13 alpha ,14 alpha -Epoxy-3 beta -methoxyserratan-21 beta -ol was found to exhibit the excellent anti-tumor promoting activity in the in vivo carcinogenesis test. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved.