Abstract 2813: The synergistic anticancer activity of 1’-acetoxychavicol acetate and sodium butyrate in human hepatocellular carcinoma cells

Introduction: It has been suggested that the combined effect of natural products may improve the effect of treatment against the proliferation of cancer cells. We evaluated the combination of 1’-acetoxychavicol acetate (ACA), obtained from Alpinia galangal, and sodium butyrate (NaB), a major short chain fatty acid, on the growth of HepG2 cells. ACA exhibits chemopreventive effects on chemically induced tumors in mouse skin as well as on rat oral, colonic, esophangeal, and pancreatic tumors. ACA also exerts antitumor activity by inducing apoptosis in various tumor cells. On the other hand, sodium butyrate has multiple effects on tumor cells cultured in vitro, including, most notably, inhibition of cell proliferation and induction of apoptosis, as well as initiating the differentiation of various carcinoma cells. The aim of our study was to elucidate the synergistic interaction of ACA and NaB on cell viability in the human hepatocellular carcinoma cell line HepG2 and to examine the mechanism of the anti-cancer effect of combined ACA and NaB treatment. Methods: HepG2 cells or HT-29 cells were cultured in Dulbecco9s modified Eagle9s medium supplemented with 10% FBS. Results: The number of HepG2 cells was synergistically decreased via apoptosis induction with the combined treatment of ACA and NaB. In ACA- and NaB-treated cells, intracellular reactive oxygen species (ROS) levels and NADPH oxidase activities were increased significantly. The decrease in cell number after combined treatment of ACA and NaB was improved with the treatment of catalase. These results suggest that an increase in intracellular ROS levels is involved in cancer cell death. AMP-activated protein kinase (AMPK) plays an essential role in controlling processes related to tumor development. In ACA- and NaB-treated cells, AMPK phosphorylation was induced significantly, and this induction improved when cells were pretreated with catalase. These results suggest that the increase in intracellular ROS is involved in the increase of AMPK phosphorylation. Conclusion: These findings are consistent with the hypothesis that combination treatments can sensitize cancer cells more effectively than individual treatments. We reported that combination treatment of ACA and NaB synergistically induced apoptotic cell death via an increase in intracellular ROS and an increase in pAMPK levels. Our findings may provide new insight into the development of novel combination therapies against hepatocellular carcinoma. Citation Format: Isao Matsui-Yuasa, Akiko Kojima-Yuasa. The synergistic anticancer activity of 1’-acetoxychavicol acetate and sodium butyrate in human hepatocellular carcinoma cells. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2813.