Cancer chemopreventive agents, serratane-type triterpenoids from Picea jezoensis

Seven serratane-type triterpenoids isolated from the cuticle of Picea jezoe nsis (Sieb. et Zucc.) Carr. jezoensis (Pinaceae) and the stein bark of Pice a jezoensis (Sieb. et Zucc.) Carr. hondoensis (Mayer) Rehder (Pinaceae) wer e studied their possible inhibitory effects on Epstein-Barr virus early ant igen (EBV-EA) activation induced by 12-O-tetradecanoylphorbol-13-acetate (T PA). All compounds showed strong inhibitory effects on the EBV-EA activatio n, being stronger than that of oleanolic acid, which exerts on cancer preve ntive activity in animal carcinogenesis models. Among these compounds, 13 a lpha, 14 alpha -epoxy-3 beta -methoxyserratan-21 beta P-ol and 3 beta -meth oxy-21 alpha -hydroxyscrrat-14-en-29-al were investigated for the inhibitor y 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 t he excellent anti-tumor promoting activity in the in vivo carcinogenesis te st. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved.