Phosphorylation of eIF4E promotes EMT and metastasis via translational control of SNAIL and MMP-3

Oncogene. 2015 Apr 16;34(16):2032-42. doi: 10.1038/onc.2014.146. Epub 2014 Jun 9.

Abstract

The progression of cancers from primary tumors to invasive and metastatic stages accounts for the overwhelming majority of cancer deaths. Understanding the molecular events which promote metastasis is thus critical in the clinic. Translational control is emerging as an important factor in tumorigenesis. The messenger RNA (mRNA) cap-binding protein eIF4E is an oncoprotein that has an important role in cancer initiation and progression. eIF4E must be phosphorylated to promote tumor development. However, the role of eIF4E phosphorylation in metastasis is not known. Here, we show that mice in which eukaryotic translation initiation factor 4E (eIF4E) cannot be phosphorylated are resistant to lung metastases in a mammary tumor model, and that cells isolated from these mice exhibit impaired invasion. We also demonstrate that transforming growth factor-beta (TGFβ) induces eIF4E phosphorylation to promote the translation of Snail and Mmp-3 mRNAs, and the induction of epithelial-to-mesenchymal transition (EMT). Furthermore, we describe a new model wherein EMT induced by TGFβ requires translational activation via the non-canonical TGFβ signaling branch acting through eIF4E phosphorylation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Line, Tumor
  • Cell Movement
  • Cell Transformation, Neoplastic / genetics
  • Epithelial-Mesenchymal Transition*
  • Eukaryotic Initiation Factor-4E / genetics
  • Eukaryotic Initiation Factor-4E / metabolism*
  • Female
  • Lung Neoplasms / genetics
  • Lung Neoplasms / secondary*
  • Mammary Neoplasms, Experimental / metabolism
  • Mammary Neoplasms, Experimental / pathology*
  • Matrix Metalloproteinase 3 / genetics
  • Matrix Metalloproteinase 3 / metabolism*
  • Mice
  • Phosphorylation
  • Protein Biosynthesis / genetics
  • RNA, Messenger / metabolism
  • Snail Family Transcription Factors
  • Transcription Factors / biosynthesis*
  • Transcription Factors / genetics
  • Transforming Growth Factor beta / metabolism*

Substances

  • Eukaryotic Initiation Factor-4E
  • RNA, Messenger
  • Snail Family Transcription Factors
  • Transcription Factors
  • Transforming Growth Factor beta
  • Matrix Metalloproteinase 3
  • Mmp3 protein, mouse