Cytotoxicity and apoptosis induction of weisiensin B isolated from Rabdosia weisiensis C.Y. Wu in human hepatoma cells.

Weisiensin B, a new ent-kaurane diterpenoid, was isolated from traditional Chinese herb Rabdosia weisiensis C.Y. Wu. In this study, cytotoxicity of weisiensin B was tested on four different tumor cell lines and the effect of growth inhibition and apoptosis in BEL-7402 cell line were investigated in vitro. The results indicated that weisiensin B had significant antiproliferation activity on the four cell lines. Further study on BEL-7402 cells involving Hoechst 33258 stain and DNA fragmentation assay revealed the characteristic apoptotic features of nuclear and DNA ladder formation. Flow cytometric (FCM) analysis with propidium iodide (PI) staining demonstrated that BEL-7402 cells treated with weisiensin B were arrested in G2/M phase. The results demonstrated that a significant fraction of weisiensin B-treated cells died by an apoptotic pathway in BEL-7402 cells. [ABSTRACT FROM AUTHOR]