Telekin suppresses human hepatocellular carcinoma cells in vitro by inducing G2/M phase arrest via the p38 MAPK signaling pathway.

OBJECTIVE

Telekin, isolated from the Chinese herb Carpesium divaricatum, has shown anti-proliferation effects against various cancer cells, including hepatocellular carcinoma cells. In this study, we investigated the anti-proliferation mechanisms of telekin in human hepatocellular carcinoma HepG2 cells in vitro.

METHODS

HepG2 cells were treated with telekin. Cell viability was evaluated using MTT assay. Flow cytometry was used to measure cell cycle profiles, ROS level and apoptosis. The protein expression levels were analyzed with Western blotting.

RESULTS

Telekin (3.75-30 μmol/L) dose-dependently inhibited the viability of HepG2 cells and induced l apoptosis. Furthermore, the treatment induced cell cycle arrest at G2/M phase, accompanied by significantly increased the phosphorylation of Cdc25A and Cdc2, and decreased Cyclin B1 level. Moreover, the treatment significantly stimulated ROS production, and increased the phosphorylation of p38 and MAPKAPK-2 in the cells. Pretreatment with the antioxidant NAC (2.5, 5, and 10 mmol/L), or the p38 MAPK inhibitor SB203580 (2.5 and 5 μmol/L) dose-dependently attenuated these telekin-induced effects in the cells.

CONCLUSIONS

Telekin suppresses hepatocellular carcinoma cells in vitro by inducing G2/M phase arrest via activating the p38 MAPK pathway.