YB-1 overexpression promotes a TGF-β1-induced epithelial-mesenchymal transition via Akt activation

Biochem Biophys Res Commun. 2015 Mar 6;458(2):347-51. doi: 10.1016/j.bbrc.2015.01.114. Epub 2015 Jan 30.

Abstract

The Y-box binding protein-1 (YB-1) is a transcription/translation regulatory protein, and the expression thereof is associated with cancer aggressiveness. In the present study, we explored the regulatory effects of YB-1 during the transforming growth factor-β1 (TGF-β1)-induced epithelial-to-mesenchymal transition (EMT) in lung adenocarcinoma cells. Downregulation of YB-1 increased E-cadherin promoter activity, and upregulation of YB-1 decreased promoter activity, suggesting that the YB-1 level may be correlated with the EMT. TGF-β1 induced YB-1 expression, and TGF-β1 translocated cytosolic YB-1 into the nucleus. YB-1 overexpression promoted TGF-β1-induced downregulation of epithelial markers, upregulation of mesenchymal markers, and cell migration. Moreover, YB-1 overexpression enhanced the expression of E-cadherin transcriptional repressors via TGF-β1-induced Akt activation. Our findings afford new insights into the role played by YB-1 in the TGF-β1 signaling pathway.

Keywords: Akt; E-cadherin; Epithelial-mesenchymal transition; TGF-β1; YB-1.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Line
  • Cell Movement / physiology
  • Cell Proliferation
  • Enzyme Activation
  • Epithelial Cells / cytology*
  • Epithelial Cells / metabolism*
  • Epithelial-Mesenchymal Transition / physiology*
  • Humans
  • Proto-Oncogene Proteins c-akt / metabolism*
  • Transforming Growth Factor beta1 / metabolism*
  • Up-Regulation
  • Y-Box-Binding Protein 1 / metabolism*

Substances

  • Transforming Growth Factor beta1
  • Y-Box-Binding Protein 1
  • YBX1 protein, human
  • Proto-Oncogene Proteins c-akt