Matrix metalloproteinase-2 cleavage of the β1 integrin ectodomain facilitates colon cancer cell motility

J Biol Chem. 2012 Oct 19;287(43):36556-66. doi: 10.1074/jbc.M112.384909. Epub 2012 Aug 16.

Abstract

Cancer cell invasion is a key element in metastasis that requires integrins for adhesion/de-adhesion, as well as matrix metalloproteinases (MMPs) for focalized proteolysis. Herein we show that MMP-2 is up-regulated in resected colorectal tumors and degrades β1 integrins with the release of fragments containing the β1 I-domain. The β1 cleavage pattern is similar to that produced by digestion of α5β1 and α2β1 with MMP-2. Two such fragments, at 25 and 75 kDa, were identified after immunoprecipitation, with monoclonal antibody BD610468 reacting with the NH(2)-terminal I-like ectodomain followed by SDS-PAGE and microsequencing using electrospray (ISI-Q-TOF-Micromass) spectrometry. Cleavage of the β1 integrin can be abolished by inhibition of MMP-2 activity; it can be induced by up-regulation of MMP-2 expression, as exemplified by HT29 colon cancer cells transfected with pCMV6-XL5-MMP-2. Co-immunoprecipitation studies of colon cancer cells showed that the β1 integrin subunit is associated with MMP-2. The MMP-2-mediated shedding of the I-like domain from β1 integrins resulted in decreased adhesion of colon cancer cells to collagen and fibronectin, thus abolishing their receptivity. Furthermore, such cells showed enhanced motility as evaluated by a "wound healing-like" assay and time-lapse microscopy, indicating their increased invasiveness. Altogether, our data demonstrate that MMP-2 amplifies the motility of colon cancer cells, not only by digesting the extracellular matrix components in the vicinity of cancer cells but also by inactivating their major β1 integrin receptors.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Adhesion / genetics
  • Cell Line, Tumor
  • Cell Movement*
  • Collagen / genetics
  • Collagen / metabolism
  • Colonic Neoplasms / genetics
  • Colonic Neoplasms / metabolism*
  • Colonic Neoplasms / pathology
  • Fibronectins / genetics
  • Fibronectins / metabolism
  • Gene Expression Regulation, Enzymologic*
  • Gene Expression Regulation, Neoplastic*
  • Humans
  • Integrin alpha2beta1 / genetics
  • Integrin alpha2beta1 / metabolism
  • Integrin alpha5beta1 / genetics
  • Integrin alpha5beta1 / metabolism
  • Integrin beta1 / genetics
  • Integrin beta1 / metabolism*
  • Matrix Metalloproteinase 2 / genetics
  • Matrix Metalloproteinase 2 / metabolism*
  • Neoplasm Proteins / genetics
  • Neoplasm Proteins / metabolism*
  • Protein Structure, Tertiary
  • Proteolysis*
  • Up-Regulation / genetics

Substances

  • Fibronectins
  • Integrin alpha2beta1
  • Integrin alpha5beta1
  • Integrin beta1
  • Neoplasm Proteins
  • Collagen
  • MMP2 protein, human
  • Matrix Metalloproteinase 2