Oncogenic targeting of BRM drives malignancy through C/EBPβ-dependent induction of α5 integrin.

TitleOncogenic targeting of BRM drives malignancy through C/EBPβ-dependent induction of α5 integrin.
Publication TypeJournal Article
Year of Publication2013
AuthorsDamiano L, Stewart KM, Cohet N, Mouw JK, Lakins JN, Debnath J, Reisman D, Nickerson JA, Imbalzano AN, Weaver VM
JournalOncogene
Date Published2013 Jun 17
ISSN1476-5594
Abstract

Integrin expression and activity are altered in tumors, and aberrant integrin signaling promotes malignancy. However, how integrins become altered in tumors remains poorly understood. We discovered that oncogenic activation of MEK signaling induces cell growth and survival, and promotes the malignant phenotype of mammary epithelial cells (MECs) by increasing α5 integrin expression. We determined that MEK activates c-Myc to reduce the transcription of the SWI/SNF chromatin remodeling enzyme Brahma (BRM). Our studies revealed that reduced BRM expression and/or activity drives the malignant behavior of MECs by epigenetically promoting C/EBPβ expression to directly induce α5 integrin transcription. Consistently, we could show that restoring BRM levels normalized the malignant behavior of transformed MECs in culture and in vivo by preventing C/EBPβ-dependent α5 integrin transcription. Our findings identify a novel mechanism whereby oncogenic signaling promotes malignant transformation by regulating transcription of a key chromatin remodeling molecule that regulates integrin-dependent stromal-epithelial interactions.Oncogene advance online publication, 17 June 2013; doi:10.1038/onc.2013.220.

DOI10.1038/onc.2013.220
Alternate JournalOncogene
PubMed ID23770848
PubMed Central IDPMC3960370
Grant ListR01 CA085492 / CA / NCI NIH HHS / United States
R01 CA138818 / CA / NCI NIH HHS / United States
U01 ES019458 / ES / NIEHS NIH HHS / United States
U54 CA143836 / CA / NCI NIH HHS / United States
U54 CA163155 / CA / NCI NIH HHS / United States
Weaver