Anti-tumor promoting activity of bufadienolides from Kalanchoe pinnata and K.
daigremontiana x tubiflora.
Supratman U(1), Fujita T, Akiyama K, Hayashi H, Murakami A, Sakai H, Koshimizu K,
(1)Division of Applied Biological Chemistry, Graduate School of Agriculture and
Life Sciences, Osaka Prefecture University, Sakai, Japan.
Five bufadienolides (1-5) isolated from the leaves of Kalanchoe pinnata and K.
daigremontiana x tubiflora (Crassulaceae) were examined for their inhibitory
effects on Epstein-Barr virus early antigen (EBV-EA) activation in Raji cells
induced by the tumor promoter, 12-O-tetradecanoylphorbol-13-acetate. All
bufadienolides showed inhibitory activity, and bryophyllin A (1) exhibited the
most marked inhibition (IC50 = 0.4 microM) among the tested compounds.
Bryophyllin C (2), a reduction analogue of 1, and bersaldegenin-3-acetate (3)
lacking the orthoacetate moiety were less active. These results strongly suggest
that bufadienolides are potential cancer chemopreventive agents.
PMID: 11388478 [Indexed for MEDLINE]