Nicotinamide inhibits growth of carcinogen induced mouse bladder tumor and human bladder tumor xenograft through up-regulation of RUNX3 and p300 - Abstract

Institute for Tumor Research and Department of Urology, College of Medicine, Cheongwon, South Korea.


Acetylation of chromatin interacting proteins is central to the epigenetic regulation of gene expression. Various tumor suppressors are inactivated by abnormal epigenetic modification. A great deal of effort has been devoted to developing anticancer agents that reactivate silenced tumor suppressors by modulating chromatin structure. Studies show that histone deacetylase inhibitors can act as anticancer agents and several histone deacetylase inhibitors are currently in clinical trials. We noted that the tumor suppressor RUNX3 is inactivated by promoter hypermethylation in human bladder cancer. We investigated whether reactivation of RUNX3 could suppress bladder cancer development in an animal model.

We analyzed RUNX3 reactivation and protein stabilization by a mild inhibitor of class III histone deacetylases, nicotinamide, by immunoprecipitation and immunoblot. Mouse bladder tumor was induced by N-butyl-N-(4-hydroxybutyl) nitrosamine. The effect of nicotinamide on Runx3 methylation status and tumor growth was measured.

Nicotinamide induced RUNX3 expression at the transcriptional and posttranslational levels in a carcinogen induced mouse bladder tumor model and in human bladder tumor xenografts. Nicotinamide effectively inhibited the growth and progression of bladder tumors without decreasing body weight.

Results suggest that nicotinamide has preventive and therapeutic effects on tumorigenesis through multiple mechanisms of RUNX3 expression up-regulation.

Written by:
Kim WJ, Lee JW, Quan C, Youn HJ, Kim HM, Bae SC.   Are you the author?

Reference: J Urol. 2011 Apr 19. Epub ahead of print.
doi: 10.1016/j.juro.2011.02.017

PubMed Abstract
PMID: 21511279 Bladder Cancer Section