In:
Cancer Research, American Association for Cancer Research (AACR), Vol. 73, No. 8_Supplement ( 2013-04-15), p. 4089-4089
Abstract:
Androgen receptor (AR) plays a pivotal role in prostate cancer. Regulation of AR transcriptional activity by post-translational modifications, such as phosphorylation by multiple kinases, is well documented. Here, we report that two PIM-1 kinase isoforms which are upregulated during prostate cancer progression, namely PIM-1S and PIM-1L, modulate AR stability and transcriptional activity through differentially phosphorylating AR at Serine 213 (S213) and Threonine 850 (T850). Although both kinases are capable of interacting with and phosphorylating AR at S213, only PIM-1L could phosphorylate T850. We also showed that PIM-1S induced S213 phosphorylation destabilizes AR by recruiting the ubiquitin E3 ligase Mdm2 and promotes AR degradation in a cell cycle dependent manner, while PIM-1L-induced T850 phosphorylation stabilizes AR by recruiting the ubiquitin E3 ligase RNF6 and promotes AR-mediated transcription under low-androgen conditions. Furthermore, both PIM-1 isoforms could promote prostate cancer cell growth under low-androgen conditions. Our data suggest that these kinases regulate AR stability and transcriptional activity through recruitment of different functional partners in a phosphorylation-dependent manner. As AR turnover has been previously shown to be critical for cell cycle progression in prostate cancer cells, PIM-1 kinase isoforms may promote prostate cancer cell growth, at least in part, through modulating AR activity via distinct mechanisms. Citation Format: Douglas Linn, Xi Yang, Yingqiu Xie, Alan Alfano, Dhanraj Deshmukh, Xin Wang, Hermela Shimelis, Hegang Chen, Wei Li, Kexin Xu, Mingyuan Chen, Yun Qiu. Differential regulation of androgen receptor by PIM-1 kinases via phosphorylation-dependent recruitment of distinct ubiquitin E3 ligases. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4089. doi:10.1158/1538-7445.AM2013-4089
Type of Medium:
Online Resource
ISSN:
0008-5472
,
1538-7445
DOI:
10.1158/1538-7445.AM2013-4089
Language:
English
Publisher:
American Association for Cancer Research (AACR)
Publication Date:
2013
detail.hit.zdb_id:
2036785-5
detail.hit.zdb_id:
1432-1
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