The Disintegrin and Metalloprotease ADAM12 Is Associated with TGF-β-Induced Epithelial to Mesenchymal Transition

PLoS One. 2015 Sep 25;10(9):e0139179. doi: 10.1371/journal.pone.0139179. eCollection 2015.


The increased expression of the Disintegrin and Metalloprotease ADAM12 has been associated with human cancers, however its role remain unclear. We have previously reported that ADAM12 expression is induced by the transforming growth factor, TGF-β and promotes TGF-β-dependent signaling through interaction with the type II receptor of TGF-β. Here we explore the implication of ADAM12 in TGF-β-mediated epithelial to mesenchymal transition (EMT), a key process in cancer progression. We show that ADAM12 expression is correlated with EMT markers in human breast cancer cell lines and biopsies. Using a non-malignant breast epithelial cell line (MCF10A), we demonstrate that TGF-β-induced EMT increases expression of the membrane-anchored ADAM12L long form. Importantly, ADAM12L overexpression in MCF10A is sufficient to induce loss of cell-cell contact, reorganization of actin cytoskeleton, up-regulation of EMT markers and chemoresistance. These effects are independent of the proteolytic activity but require the cytoplasmic tail and are specific of ADAM12L since overexpression of ADAM12S failed to induce similar changes. We further demonstrate that ADAM12L-dependent EMT is associated with increased phosphorylation of Smad3, Akt and ERK proteins. Conversely, inhibition of TGF-β receptors or ERK activities reverses ADAM12L-induced mesenchymal phenotype. Together our data demonstrate that ADAM12L is associated with EMT and contributes to TGF-β-dependent EMT by favoring both Smad-dependent and Smad-independent pathways.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • ADAM Proteins / metabolism*
  • ADAM12 Protein
  • Adult
  • Aged
  • Aged, 80 and over
  • Biocatalysis / drug effects
  • Biomarkers, Tumor / metabolism
  • Breast Neoplasms / genetics
  • Cell Line, Tumor
  • Cytoplasm / metabolism
  • Drug Resistance, Neoplasm / drug effects
  • Drug Resistance, Neoplasm / genetics
  • Epithelial Cells / drug effects
  • Epithelial Cells / metabolism
  • Epithelial-Mesenchymal Transition / drug effects*
  • Female
  • Humans
  • MAP Kinase Signaling System / drug effects
  • Membrane Proteins / metabolism*
  • Mesoderm / metabolism
  • Middle Aged
  • Phenotype
  • Receptors, Transforming Growth Factor beta / metabolism
  • Signal Transduction / drug effects
  • Signal Transduction / genetics
  • Transforming Growth Factor beta / pharmacology*


  • Biomarkers, Tumor
  • Membrane Proteins
  • Receptors, Transforming Growth Factor beta
  • Transforming Growth Factor beta
  • ADAM Proteins
  • ADAM12 Protein
  • ADAM12 protein, human

Grants and funding

This work was supported by the Institut National de la Santé et de la Recherche Médicale, the Ligue Nationale Contre le Cancer. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.