Krüppel-like factor 4 is involved in cell scattering induced by hepatocyte growth factor

J Cell Sci. 2012 Oct 15;125(Pt 20):4853-64. doi: 10.1242/jcs.108910. Epub 2012 Aug 1.

Abstract

Hepatocyte growth factor/scatter factor (HGF) is unique by inducing epithelial cell scattering, a cellular event pivotal to HGF-mediated invasive-growth response essential for embryonic development and metastasis. Krüppel-like factor 4 (KLF4) is a multifunctional zinc-finger transcription factor involved in cell proliferation, differentiation and self-renewal. We herein present the first evidence for the functional connection between KLF4 and HGF-induced cell scattering. In particular, we found that KLF4 was upregulated by HGF in two independent epithelial cell types, HepG2 and MDCK, whereas KLF4 knockdown inhibited HGF-induced E-cadherin suppression and cell scattering. Moreover, enforced nuclear KLF4 expression alone was sufficient to upregulate KLF4, downregulate E-cadherin and trigger scattering. Chromatin immunoprecipitation (ChIP) analysis further revealed that KLF4 induced suppression of E-cadherin transcription by directly binding to the E-cadherin promoter. Additionally, we proved that HGF-induced upregulation of KLF4 transcription and cell scattering require activation of the MEK/ERK signaling pathway and the induction of early growth response 1 (EGR-1). At the mechanistic level, ChIP analysis validated a direct binding of EGR-1 to the KLF4 promoter to induce KLF4 transcription; in turn, EGR-1-induced KLF4 binds to its own promoter, thus creating a positive feedback mechanism to sustain KLF4 expression and the resultant cell scattering. We conclude that KLF4 upregulation by HGF represents a novel mechanism mediating HGF-induced cell scattering and perhaps other associated events such as cell migration and invasion.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cadherins / genetics
  • Cadherins / metabolism
  • Cell Movement / genetics*
  • Dogs
  • Early Growth Response Protein 1 / genetics
  • Early Growth Response Protein 1 / metabolism
  • Embryonic Development / genetics
  • Epithelial Cells* / cytology
  • Epithelial Cells* / metabolism
  • Gene Expression Regulation
  • Hep G2 Cells
  • Hepatocyte Growth Factor* / genetics
  • Hepatocyte Growth Factor* / metabolism
  • Humans
  • Kruppel-Like Factor 4
  • Kruppel-Like Transcription Factors* / genetics
  • Kruppel-Like Transcription Factors* / metabolism
  • MAP Kinase Signaling System
  • Madin Darby Canine Kidney Cells
  • Neoplasm Invasiveness
  • Neoplasm Metastasis / genetics
  • Signal Transduction

Substances

  • Cadherins
  • EGR1 protein, human
  • Early Growth Response Protein 1
  • KLF4 protein, human
  • Kruppel-Like Factor 4
  • Kruppel-Like Transcription Factors
  • Hepatocyte Growth Factor