Loss of FOXA1/2 is essential for the epithelial-to-mesenchymal transition in pancreatic cancer

Cancer Res. 2010 Mar 1;70(5):2115-25. doi: 10.1158/0008-5472.CAN-09-2979. Epub 2010 Feb 16.

Abstract

FOXA1 and FOXA2, members of the forkhead transcription factor family, are critical for epithelial differentiation in many endoderm-derived organs, including the pancreas. However, their role in tumor progression is largely unknown. Here, we identified FOXA1 and FOXA2 as important antagonists of the epithelial-to-mesenchymal transition (EMT) in pancreatic ductal adenocarcinoma (PDA) through their positive regulation of E-cadherin and maintenance of the epithelial phenotype. In human PDA samples, FOXA1/2 are expressed in all epithelia from normal to well-differentiated cancer cells, but are lost in undifferentiated cancer cells. In PDA cell lines, FOXA1/2 expression is consistently suppressed in experimental EMT models and RNAi silencing of FOXA1/2 alone is sufficient to induce EMT. Conversely, ectopic FOXA1/2 expression can potently neutralize several EMT-related E-cadherin repressive mechanisms. Finally, ectopic FOXA2 expression could reactivate E-cadherin expression in a PDA cell line with extensive promoter hypermethylation. In fact, demethylation-mediated reactivation of E-cadherin expression in these cells required concurrent reactivation of endogenous FOXA2 expression. We conclude that suppression of FOXA1/2 expression is both necessary and sufficient for EMT during PDA malignant progression.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cadherins / biosynthesis
  • Cadherins / genetics
  • Cadherins / metabolism
  • DNA Methylation
  • Epithelial Cells / pathology
  • Gene Silencing
  • Hepatocyte Nuclear Factor 3-alpha / biosynthesis*
  • Hepatocyte Nuclear Factor 3-alpha / genetics
  • Hepatocyte Nuclear Factor 3-beta / biosynthesis*
  • Hepatocyte Nuclear Factor 3-beta / genetics
  • Humans
  • Immunohistochemistry
  • Mesoderm / pathology
  • Pancreatic Neoplasms / genetics
  • Pancreatic Neoplasms / metabolism*
  • Pancreatic Neoplasms / pathology*
  • Promoter Regions, Genetic
  • RNA, Small Interfering / genetics
  • Transfection

Substances

  • Cadherins
  • FOXA1 protein, human
  • FOXA2 protein, human
  • Hepatocyte Nuclear Factor 3-alpha
  • RNA, Small Interfering
  • Hepatocyte Nuclear Factor 3-beta