Abstract 1773: MHY-449 induces apoptotic cell death through ROS- and caspase-dependent pathways in AGS human gastric cancer cells

Abstract We previously reported on the anticancer effect of the diastereoisomeric compound MHY-449, a novel dihydrobenzofuro[4,5-b][1,8] naphthyridin-6-one derivative, in various human cancer cells such as HCT116 human colon cancer cells (Int J Oncol 41: 2057-64, 2012) and PC3 human prostate cancer cells (Int J Oncol 44: 905-11, 2014). In this study, we investigated whether MHY-449 has anticancer properties in AGS human gastric cancer cells, and if so, what the molecular mechanisms are. Treatment with MHY-449 inhibited cell growth and induced apoptotic cell death in a concentration-dependent manner. The induction of apoptosis was determined by morphological changes, Hoechst 33342 staining, DNA fragmentation, increase of late apoptosis and sub-G1 DNA which were detected by flow cytometry analysis. Western blot analysis showed that MHY-449 upregulated the levels of Fas, FasL, p53, p21WAF1/CIP1, p27KIP1 and the ratio of Bax/Bcl-2 and downregulated the levels of procaspase-8, -9 and -3 and the cleavage of poly(ADP-ribose) polymerase (PARP). The apoptotic cell death induced by MHY-449 was accompanied by the activation of caspase-8, -9 and -3, which was completely abrogated by the pan-caspase inhibitor, z-VAD-FMK. In addition, treatment with MHY-449 elevated the level of cellular ROS generation. These data were further confirmed by incubating the cells with N-acetyl-L-cysteine (NAC), which is a scavenger of ROS. Pretreatment with NAC protected against MHY-449-induced cytotoxicity. Similarly, pretreatment of NAC abolished MHY-449-induced downregulation of pro-caspase-8, -9 and -3 and PARP cleavage. Taken together, these findings suggest that MHY-449 induces apoptosis via caspase- and ROS-dependent pathways in AGS human gastric cancer cells. Citation Format: Yung Hyun Choi, Yong Jung Kang, Seon Hee Kim, Bokyung Sung, Dong Hwan Kim, Seong Yeon Hwang, Minjung Kim, Hyun Sook Lim, Jeong-Hyun Yoon, Hyung Ryong Moon, Hae Young Chung, Nam Deuk Kim. MHY-449 induces apoptotic cell death through ROS- and caspase-dependent pathways in AGS human gastric cancer cells. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1773. doi:10.1158/1538-7445.AM2015-1773