Open AccessThe Sirtuin Inhibitor Tenovin-6 Upregulates Death Receptor 5 and Enhances Cytotoxic Effects of 5-Fluorouracil and Oxaliplatin in Colon Cancer Cells
Author(s) -
Takayoshi Ueno,
Shunsuke Endo,
Rie Saito,
Masao Hirose,
Sachiko Hirai,
Hideo Suzuki,
Yamato Kikkawa,
Ichinosuke Hyodo
Publication year - 2014
Publication title -
oncology research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.267
H-Index - 57
eISSN - 1555-3906
pISSN - 0965-0407
DOI - 10.3727/096504013x13854886566598
Subject(s) - oxaliplatin , cancer research , apoptosis , colorectal cancer , histone deacetylase inhibitor , irinotecan , chemistry , cancer , histone deacetylase , biology , medicine , biochemistry , histone , gene
It has been reported that upregulated SIRT1 (NAD + -dependent class III histone deacetylase) deacetylates the p53 protein, represses its function, and allows for tumor cell growth in various cancers. Here we investigated antitumor effects of tenovin-6, a small-molecule inhibitor of SIRT1 and SIRT2, in various colon cancer cell lines. Tenovin-6 induced apoptosis in all five colon cancer cell lines investigated (two cell lines with wild-type p53 and three with mutant p53 ) regardless of the p53 mutation status. This effect was accompanied by accumulation of death receptor 5 (DR5) in most cell lines. DR5 silencing in HCT116 cells strongly attenuated tenovin-6-induced apoptosis. We investigated the effect of combining tenovin-6 with conventional anticancer agents 5-fluorouracil (5-FU), SN-38 (an active metabolite of irinotecan), and oxaliplatin. Synergistic antitumor effects of tenovin-6 were observed in combination with either 5-FU or oxaliplatin in vitro. The combination of tenovin-6 and oxaliplatin exhibited potent growth inhibition of HCT116 xenograft tumors in vivo. In conclusion, tenovin-6 induced apoptosis in human colon cancer cells through the activation of the DR5 signaling pathway and enhanced the antitumor properties of 5-FU and oxaliplatin. These results may help develop a novel treatment option for colorectal cancer using a SIRT inhibitor.