Abstract 1861: The role and regulation of MTA1-ETS2 axis in prostate cancer

Abstract

Abstract Overexpression of the chromatin modifier protein, metastasis associated 1 (MTA1) in prostate cancer contributes to tumor aggressiveness, but the molecular mechanism involved has not been fully elucidated. MTA1 ChIP-Seq analysis in prostate tissues from the prostate-specific Pten heterozygous mice, which exhibit elevated levels of MTA1 revealed MTA1 recruitment onto the ETS2 promoter. Loss of function studies with MTA1 in various prostate cancer cell lines exhibited reduced expression for ETS2 at both mRNA and protein levels. We also observed increased expression of ETS2 at both mRNA and protein levels in prostate tissues from the prostate-specific MTA1 transgenic mice. Meta-analysis of prostate cancer samples in the GEO database exhibited a positive correlation between MTA1 and ETS2 levels. These results suggested that MTA1 functions as a coactivator for regulating ETS2 expression in prostate cancer. We found direct interaction between MTA1 and ETS2 in cells expressing ectopic MTA1 and ETS2. Interestingly, the prostate-specific Pten heterozygous mice, when fed with diet supplemented with pterostilbene, a natural pharmacological inhibitor of MTA1, showed a decrease in ETS2 mRNA and protein levels, perhaps due to decreased recruitment of MTA1 onto the ETS2 promoter. These results suggest that MTA1 functions as a coactivator for regulating ETS2 expression in prostate cancer at the transcriptional level and co-operates with ETS2 to promote prostate cancer progression. At the same time, pterostilbene may become a novel chemopreventive and therapeutic candidate for clinical development in prostate cancer due to its ability to target the MTA1-ETS2 axis. Citation Format: Avinash Kumar, Swati Dhar, Nasir Butt, Agnes Rimando, Luis Martinez, Anait Levenson. The role and regulation of MTA1-ETS2 axis in prostate cancer. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 1861.