Combination treatment with fasudil and clioquinol produces synergistic anti-tumor effects in U87 glioblastoma cells by activating apoptosis and autophagy

Survival of patients with glioblastoma (GBM) remains poor, and novel treatment methods are urgently needed. In this study, we tested the effects of a combination of fasudil, a ROCK inhibitor, and clioquinol, an 8-hydroxyquinoline derivative with antimicrobial properties, on human GBM U87 cells. Combination treatment synergistically inhibited the viability of glioma cells but not mouse normal neuron HT22 cells and significantly induced mitochondria-mediated apoptosis. Moreover, the combination was also found to trigger macro-autophagy (henceforth referred to as autophagy) by increasing the expression levels of several proteins involved in the induction of autophagy. Further studies showed that 3-methyladenine (3-MA) or chloroquine (CQ), two autophagy inhibitors, abrogated the cytotoxic effects of the combination treatment as well as the autophagy. Overall, we demonstrated that fasudil and clioquinol show synergistic anti-cancer effects, providing evidence for the further development of combination therapy for GBM.