Abstract

Glioblastoma multiforme is the most common and lethal primary brain tumor that responds poorly to currently available chemotherapy. Vitexicarpin, a flavonoid compound has been reported to exhibit anti-proliferative activities against various cancer cell lines. However, the anticancer effect of vitexicarpin on glioblastoma remains unexplored. In the present study, we found that vitexicarpin inhibited the growth of U87 glioblastoma cells in a dose-dependent manner with IC₅₀ ~22 µM. Vitexicarpin-induced growth inhibition was found to be associated with induction of apoptosis and mitotic arrest. During vitexicarpin-induced apoptosis, up-regulation of Bax, down-regulation of Bcl-2 and cleavage of caspase-3 and poly (ADP-ribose) polymerase (PARP) were observed. We also found that vitexicarpin induced mitotic arrest by inhibiting tubulin polymerization. Furthermore, pretreatment of cells with z-VAD-fmk reversed the apoptotic effect of vitexicarpin but failed to attenuate mitotic arrest. Taken together, our data revealed that vitexicarpin inhibited the growth of U87 cells by induction of apoptosis and mitotic arrest. Thus, vitexicarpin may be a promising candidate for the treatment of glioblastoma.

Key words: Vitexicarpin, glioblastoma, mitotic arrest, apoptosis, caspase-3.