Loss of E-cadherin activates EGFR-MEK/ERK signaling, which promotes invasion via the ZEB1/MMP2 axis in non-small cell lung cancer

Oncotarget. 2013 Dec;4(12):2512-22. doi: 10.18632/oncotarget.1463.

Abstract

Loss of E-cadherin, a hallmark of epithelial-mesenchymal transition (EMT), can significantly affect metastatic dissemination. However, the molecular mechanism of EMT-associated metastatic dissemination by loss of E-cadherin still remains unclear in non-small cell lung cancers (NSCLCs). In the present study, we show that the knockdown of E-cadherin was sufficient to convert A549 NSCLC cells into mesenchymal type with the concurrent up-regulation of typical EMT inducers such as ZEB1 and TWIST1. Interestingly, the EMT-induced cells by E-cadherin depletion facilitate invasion in a matrix metalloproteinase-2 (MMP2)-dependent manner with aberrant activation of EGFR signaling. We demonstrated that the elevated invasiveness was a result of the activated EGFR-MEK/ERK signaling, which in turn leads to ZEB1 dependent MMP2 induction. These results suggest that the EGFR-MEK/ERK/ZEB1/MMP2 axis is responsible for promoted invasion in EMT-induced NSCLCs. Consistently, ERK activation and loss of E-cadherin were both observed in the disseminating cancer cells at the invasive tumor fronts in NSCLS cancer tissues. Thereby, these data suggest that the EGFR-MEK/ERK signaling would be a promising molecular target to control aberrant MMP2 expression and consequent invasion in the EMT-induced NSCSLs.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cadherins / deficiency*
  • Cadherins / genetics
  • Cadherins / metabolism
  • Carcinoma, Non-Small-Cell Lung / enzymology
  • Carcinoma, Non-Small-Cell Lung / genetics
  • Carcinoma, Non-Small-Cell Lung / metabolism*
  • Carcinoma, Non-Small-Cell Lung / pathology
  • Cell Growth Processes / physiology
  • Cell Line, Tumor
  • Epithelial-Mesenchymal Transition
  • ErbB Receptors / metabolism*
  • Gene Expression Regulation, Neoplastic
  • Gene Knockdown Techniques
  • Humans
  • Lung Neoplasms / enzymology
  • Lung Neoplasms / genetics
  • Lung Neoplasms / metabolism*
  • Lung Neoplasms / pathology
  • MAP Kinase Signaling System / genetics
  • MAP Kinase Signaling System / physiology*
  • Matrix Metalloproteinase 2 / metabolism*

Substances

  • Cadherins
  • EGFR protein, human
  • ErbB Receptors
  • MMP2 protein, human
  • Matrix Metalloproteinase 2