Growth inhibition and apoptosis induction in human hepatoma cells by tanshinone II A

Abstract

In order to study the effect of tanshinone II A on growth and apoptosis in human hepatoma cell line BEL-7402 in vitro, the human hepatoma cell line BEL-7402 was treated with tanshinone II A at various concentrations for 72 h. Growth suppression was evaluated by MTT assay; apoptosis-related alterations in morphology and biochemistry were ascertained under cytochemical staining (Hoechst 33258), transmission electron microscopy (TEM), and DNA agarose gel electrophoresis. Apoptotic rate was quantified by flow cytometry (FCM). The results showed that Tanshinone II A could inhibit the growth of hepatoma cells in a dose-dependent manner, with IC50 value being 6.28 micrograms/ml. After treatment with 1-10 micrograms/ml tanshinone II A for 72 h, BEL-7402 cells apoptosis with nuclear chromatin condensation and fragmentation as well as cell shrinkage and the formation of apoptotic bodies were observed. DNA ladder could be demonstrated on DNA electrophoresis. FCM analysis showed hypodiploid peaks on histogram, and the apoptotic rates at 5 micrograms/ml concentration for 12 h, 24 h, 36 h, 48 h and 72 h were (2.32 +/- 0.16)%, (3.01 +/- 0.35)%, (3.87 +/- 0.43)%, (6.73 +/- 0.58)% and (20.85 +/- 1.74)% respectively, which were all significantly higher than those in the control group (1.07 +/- 0.13)%. It is concluded that Tanshinone II A could induce human hepatoma cell line BEL-7402 apoptosis, which may be related to the mechanism of growth inhibition.