DICO, a novel nonaromatic B-ring flavonoid, induces G2/M cell cycle arrest and apoptosis in human hepatoma cells

DICO was a novel nonaromatic B-ring flavonoid obtained from Macrothelypteris torresiana. In the present work, we investigated the antitumor activity and the antineoplastic mechanism of DICO. Our study showed that DICO inhibited the growth of HepG2 cells in dose and time-dependent manners. As well as DICO induced G2/M cell cycle arrest and apoptosis via a ROS-mediated mitochondrial pathway. Western blot assay demonstrated that DICO decreased Bcl-2 level and induced Bax translocation to cause cytochrome c release. Subsequently, caspase-9 and caspase-3 were activated. Meanwhile, the alterations of cyclin A and B1, p-CDK1 and p-cdc25c levels were also observed in response to DICO treatment. Taken together, DICO displayed a significant antitumor effect through G2/M cell cycle arrest and apoptosis induction, which suggested DICO might have therapeutic potential against tumors.