Positive expression of E-cadherin suppresses cell adhesion to fibronectin via reduction of alpha5beta1 integrin in human breast carcinoma cells

J Cancer Res Clin Oncol. 2006 Dec;132(12):795-803. doi: 10.1007/s00432-006-0128-2. Epub 2006 Jul 5.

Abstract

E-cadherin mainly mediated the epithelial cell-cell adhesion, and integrin signaling can modulate the signaling pathway of E-cadherin in the different levels. Up to now, however, it is still unclear that whether E-cadherin could interfere with cell-matrix interaction, a typical adhesion through integrins. In this study we investigated the effects of E-cadherin on cell-matrix adhesion and alpha5beta1 integrin expression in human breast carcinoma cells. It was found that either mRNA or protein level of alpha5 and beta1 subunits of integrin decreased in E-cad-231 compared with Mock-231. Furthermore, the promoter activity of alpha5 gene was inhibited in E-cad-231 compared with Mock-231. Consistently, phosphorylated focal adhesion kinase, a closer key downstream protein kinase of integrin signaling, were also down-regulated in E-cad-231. Furthermore, distribution of beta-catenin was observed and data showed beta-catenin was accumulated in the nucleus in Mock-231, while disappeared from the nucleus and mainly accumulated near the cell surface membrane in E-cad-231. LiCl, a molecule that can inhibit the GSK-3beta activity and down-regulate beta-catenin degradation, could inversely stimulate expression of alpha5 and beta1 integrin. Taken together, these results indicated that positive expression of E-cadherin inhibits the cell adhesion to extracellular matrix mediated by alpha5beta1 integrin signaling.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Breast Neoplasms / genetics
  • Breast Neoplasms / metabolism*
  • Cadherins / biosynthesis*
  • Cadherins / genetics*
  • Cell Adhesion / genetics
  • Cell Line, Tumor
  • Extracellular Matrix / metabolism
  • Female
  • Fibronectins / drug effects
  • Fibronectins / metabolism*
  • Gene Expression Profiling
  • Humans
  • Integrin alpha5beta1 / genetics
  • Integrin alpha5beta1 / metabolism*
  • Phosphorylation
  • RNA, Messenger / biosynthesis
  • RNA, Messenger / genetics
  • Reverse Transcriptase Polymerase Chain Reaction
  • Transfection
  • Tumor Cells, Cultured
  • Tyrosine / metabolism
  • beta Catenin / metabolism

Substances

  • Cadherins
  • Fibronectins
  • Integrin alpha5beta1
  • RNA, Messenger
  • beta Catenin
  • Tyrosine