Induction of mitotic arrest and apoptosis by salvianolic acid C in human hepatoma HepG2 cells

Aim To investigate the inhibitory effect of salvianolic acid C against human tumor cells and the related mechanisms.Methods In vitro growth inhibitory effect on a variety of tumor cell lines was determined by MTT assay.Cell cycle distribution and apoptosis were detected by flow cytometry.Giemsa staining was performed to demonstrate the morphological features of cells in mitotic phase.Polymerization of tubulin was detected by tubulin assembly assay.Activation of Caspase-3 and Caspase-6 was measured by colorimetric assay.Results MTT assay showed that salvianolic acid C inhibited the proliferation of several cancer cell lines,in which human hepatocellular cancer HepG2 cells exhibited the highest susceptibility to salvianolic acid C.HepG2 cells were markedly arrested in G2 /M phase and progressed into apoptosis after the treatment of salvianolic acid C.Increased activities of Caspase-3 and Caspase-6 in HepG2 cells were observed.Giemsa staining indicated mitotic blockade by salvianolic acid C.The drug also inhibited tubulin polymerization.Conclusions Salvianolic acid C displays antiproliferative effect on cancer cells.It blocks cell cycle through inhibiting tubulin polymerization and then induces apoptosis.