Vitexicarpin, a flavonoid from Vitex trifolia L., induces apoptosis in K562 cells via mitochondria-controlled apoptotic pathway
Wang, H-yan.; Cai, B.; Cui, C-bin.; Zhang, D-yun.; Yang, B-feng.
Yao Xue Xue Bao 40(1): 27-31
2005
ISSN/ISBN: 0513-4870 PMID: 15881322 Document Number: 589437
Aim: To investigate the inhibitory effect of vitexicarpin on the proliferation of human cancer cells and its mechanism of action. Methods: The inhibitory effect of vitexicarpin on the proliferation of human cancer cells was evaluated by the SRB method and its apoptosis-inducing effect was demonstrated by morphological observation under light microscope, flow cytometric analysis and agarose gel electrophoresis. The proteins related to apoptosis were examined by Western blotting analysis. Results: Vitexicarpin significantly inhibited the proliferation of human cancer cells, A2780, HCT-15, HT-1080 and K562, with the IC50 values of (19.1+or-2.4) micro mol/litre-1 for A2780 (48 h), (0.66+or-0.10) micro mol/litre-1 for HCT-15 (48 h), (0.44+or-0.06) micro mol/litre-1 for HT-1080 (48 h) and (0.28+or-0.14) micro mol/litre-1 for K562 (24 h). The cells treated with vitexicarpin showed characteristic morphology typical for apoptosis and gave dose-dependent sub-G0/G1 peak in the flow cytometric analysis and DNA ladder on agarose gel electrophoresis. In Western blotting analysis, the cleavage of PARP and caspase-3, the release of cytochrome c from mitochondria into the cytosol, the decrease of Bcl-2 expression level, and the down-regulation of the ratio of Bcl-2/Bax expression level were examined in the K562 cells treated with vitexicarpin. Conclusion: Vitexicarpin induces apoptosis in K562 cells via mitochondria-controlled apoptotic pathway.