Makoto Okawaki

Abstract 1757: The new molecular target therapy of Hsp90 inhibition in esophageal squamous cell carcinoma

Heat shock protein 90 (HSP90) has numerous cellular functions, including promotion of proper protein folding, and stabilizes a number of oncogenic proteins, many of which are overexpressed in cancers. The objective of this study is to evaluate an antitumor effect of HSP90 inhibitor, AUY922, in esophageal squamous cell carcinoma(ESCC) cell lines. ESCC cell lines were treated with AUY922 to examine the effect on proliferation assay, apoptosis assay, Western blotting, and chemotaxis assay. AUY922 inhibited cell proliferation in ESCC cells in a dose- and time-dependent manner. Growth inhibitory effect of AUY922 for ESCC cells was higher than CDDP. With flowcytometry and immunostaining, we showed that AUY922 induced apoptosis in ESCC cells and inhibited chemotaxis of ESCC cells. These antitumor effects of AUY922 were due to inhibition of cell proliferation through suppression of phosphorylation of the client proteins. The HSP90 inhibitor is useful as an antitumor drug in ESCC by inhibiting proliferation of ESCC cells through novel mechanism. Citation Format: Masahiro Yamamura, Tsutomu Nohno, Akira Yamauchi, Naoki Katase, Makoto Okawaki, Akira Sawaki, Hideo Matsumoto, Toshihiro Hirai, Yoshiyuki Yamaguchi. The new molecular target therapy of Hsp90 inhibition in esophageal squamous cell carcinoma. [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 1757. doi:10.1158/1538-7445.AM2015-1757