학술논문

Complex regulation of LCoR signaling in breast cancer cells
Original Article
Document Type
Academic Journal
Source
Oncogene. August 17, 2017, Vol. 36 Issue 33, 4790
Subject
Care and treatment
Research
Estrogen receptors -- Research
Cell proliferation -- Research
Cancer cells -- Research
Breast cancer -- Care and treatment
Gene expression -- Research
Language
English
ISSN
0950-9232
Abstract
Author(s): S Jalaguier [1, 2, 3, 4]; C Teyssier [1, 2, 3, 4]; T Nait Achour [1, 2, 3, 4]; A Lucas [1, 2, 3, 4]; S Bonnet [1, 2, [...]
Ligand-dependent corepressor (LCoR) is a transcriptional repressor of ligand-activated estrogen receptors (ERs) and other transcription factors that acts both by recruiting histone deacetylases and C-terminal binding proteins. Here, we first studied LCOR gene expression in breast cancer cell lines and tissues. We detected two mRNAs variants, LCoR and LCoR2 (which encodes a truncated LCoR protein). Their expression was highly correlated and localized in discrete nuclear foci. LCoR and LCoR2 strongly repressed transcription, inhibited estrogen-induced target gene expression and decreased breast cancer cell proliferation. By mutagenesis analysis, we showed that the helix-turn-helix domain of LCoR is required for these effects. Using in vitro interaction, coimmunoprecipitation, proximity ligation assay and confocal microscopy experiments, we found that receptor-interacting protein of 140 kDa (RIP140) is a LCoR and LCoR2 partner and that this interaction requires the HTH domain of LCoR and RIP140 N- and C-terminal regions. By increasing or silencing LCoR and RIP140 expression in human breast cancer cells, we then showed that RIP140 is necessary for LCoR inhibition of gene expression and cell proliferation. Moreover, LCoR and RIP140 mRNA levels were strongly correlated in breast cancer cell lines and biopsies. In addition, RIP140 positively regulated LCoR expression in human breast cancer cells and in transgenic mouse models. Finally, their expression correlated with overall survival of patients with breast cancer. Taken together, our results provide new insights into the mechanism of action of LCoR and RIP140 and highlight their strong interplay for the control of gene expression and cell proliferation in breast cancer cells. Oncogene (2017) 36, 4790-4801; doi: 10.1038/onc.2017.97; published online 17 April 2017