Combination treatment of ergosterol followed by amphotericin B induces necrotic cell death in human hepatocellular carcinoma cells

The incidence of liver cancer, the second leading cause of cancer-related deaths has increased over the past few decades. Although recent treatments such as sorafenib are promising in patients with advanced hepatocellular carcinoma (HCC), the response rates remain poor thereby warranting the identification of novel therapeutic agents against liver cancer. Herein, we investigated the anti-cancer effect of ergosterol (a secondary metabolite in medicinal fungus) pretreatment followed by amphotericin B (AmB) treatment on liver cancer cell lines. We demonstrated that pretreatment with a nontoxic dose of ergosterol synergistically enhanced the cytotoxicity of AmB in both Hep3B and HepJ5 cells. The combination treatment-mediated suppression of cancer cell viability occurred through necrosis characterized by disrupted cell membrane and significant amounts of debris accumulation. In addition, we also observed a concomitant increase in reactive oxygen species (ROS) and LC3-II levels in HepJ5 cells treated with ergosterol and AmB. Our results suggest that ergosterol-AmB combination treatment effectively induced necrotic cell death in cancer cells, and deserves further evaluation for development as an anti-cancer agent.