Hepatoma CSCs are also considered a pivotal target for cancer eradication, and liver CSCs have been identified

using stem cell markers such as EpCAM. Thus, we assessed the Notch-related effect by analyzing EpCAM+ features in vitro and in vivo. Methods: We inhibited the Notch receptor by using β-secretase inhibitors (GSIs; L-685,458 and DAPT) and examined the cell growth of the hepatoma cell lines Huh7, HepG2, HLE, and SKHep1 to assess their notch-modulating effect in hepatoma. We inoculated NOD-SCID mice with Huh7 cells and compared the degree of Notch inhibition, tumor growth, and survival by administering GSIs percutaneously. We evaluated EpCAM expression by immunohistochemistry in the inoculated hepatoma mouse tissues. We then distinguished the EpCAM+ and EpCAM- fractions of the hepatoma cells using fluorescence-activated cell sorting. The cells were cultured to compare the effects LY294002 of cell growth by administering GSIs. Results: GSIs administered to the AFP-producing Huh7 and HepG2 cells significantly selleck screening library suppressed cell growth after 5 days (Huh7 by L-685,458: p<0.001, Huh7 by DAPT: p<0.01, HepG2 by DAPT: p<0.01) compared with AFP-negative HLE and SKHep1 cells. GSIs reduced subcutaneous tumor growth in the inoculated

NOD-SCID mice compared with inhibitor-negative controls (p<0.05); when the tumors were allowed to grow, the control mice died earlier (p<0.005). Histologically, caspase 8,

EpCAM and HE staining revealed spacious apop-totic and necrotic areas in the hepatoma cells in the GSI-treated mice, along with a diminished number of active hepatoma cells and EpCAM+ features. Cell growth after administering DAPT was associated with significant suppression of EpCAM+ cells compared with EpCAM- cells (p<0.01). ADAMTS5 This suppression was 20% more effective than in the non-sorted Huh7 cells. Moreover, L-685,458 efficiently suppressed both EpCAM+ and EpCAM- cells (p<0.01). Conclusion: Notch signaling is activated in hepatoma cells, especially in AFP-producing and EpCAM+ cells. Notch-inactivating therapy could effective for targeting liver CSCs. Disclosures: Hikari Okada – Employment: Kanazawa University Shuichi Kaneko – Grant/Research Support: MDS, Co., Inc, Chugai Pharma., Co., Inc, Toray Co., Inc, Daiichi Sankyo., Co., Inc, Dainippon Sumitomo, Co., Inc, Ajinomoto Co., Inc, MDS, Co., Inc, Chugai Pharma., Co., Inc, Toray Co., Inc, Daiichi Sankyo., Co., Inc, Dainippon Sumitomo, Co., Inc, Ajinomoto Co., Inc, Bayer Japan The following people have nothing to disclose: Kazunori Kawaguchi, Masao Honda, Taro Yamashita, Kouki Nio, Masashi Nishikawa, Kuniaki Arai, Yoshio Sakai, Tatsuya Yamashita, Eishiro Mizukoshi Background and Aim: Among the organelle, the main generator of ROS is mitochondria, where electron transport chain produces ATP by oxidative phosphorylation.