Epidermal growth factor receptor/beta-catenin/T-cell factor 4/matrix metalloproteinase 1: a new pathway for regulating keratinocyte invasiveness after UVA irradiation

Cancer Res. 2009 Apr 15;69(8):3291-9. doi: 10.1158/0008-5472.CAN-08-1909. Epub 2009 Mar 31.

Abstract

Previous studies have established that UV irradiation results in epidermal growth factor receptor (EGFR) activation in keratinocytes. However, the signaling pathways and cellular effects related to this process remain incompletely elucidated. Herein, we describe for the first time that UVA-mediated EGFR activation results in beta-catenin tyrosine phosphorylation at the Y654 residue responsible for the dissociation of E-cadherin/alpha-catenin/beta-catenin complexes. Moreover, UVA induces an EGFR-dependent, but Wnt-independent, beta-catenin relocalization from the membrane to the nucleus followed by its association with T-cell factor 4 (TCF4). This newly formed beta-catenin/TCF4 complex binds to a specific site on matrix metalloproteinase 1 (MMP1) promoter and governs MMP1 gene and protein expression, as well as cell migration in collagen and gelatin. Altogether, these results suggest that UVA stimulates keratinocyte invasiveness through two coordinated EGFR-dependent processes: loss of cell-to-cell contact due to beta-catenin/E-cadherin/alpha-catenin dissociation and increased cell migration through extracellular matrix component degradation due to beta-catenin/TCF4-dependent MMP1 regulation. These events may represent an important step in epidermis repair following UVA injury and their abnormal regulation could contribute to photoaging and photocarcinogenesis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Adhesion / physiology
  • ErbB Receptors / metabolism*
  • Humans
  • Keratinocytes / metabolism*
  • Keratinocytes / radiation effects*
  • Matrix Metalloproteinase 1 / metabolism*
  • Phosphorylation / radiation effects
  • Signal Transduction / radiation effects
  • TCF Transcription Factors / metabolism*
  • Transcription Factor 7-Like 2 Protein
  • Transcription, Genetic / radiation effects
  • Ultraviolet Rays
  • beta Catenin / metabolism*

Substances

  • CTNNB1 protein, human
  • TCF Transcription Factors
  • TCF7L2 protein, human
  • Transcription Factor 7-Like 2 Protein
  • beta Catenin
  • ErbB Receptors
  • MMP1 protein, human
  • Matrix Metalloproteinase 1