Stabilization of phenotypic plasticity through mesenchymal-specific DNA hypermethylation in cancer cells

Oncogene. 2012 Apr 12;31(15):1963-74. doi: 10.1038/onc.2011.373. Epub 2011 Aug 29.

Abstract

The epithelial-mesenchymal transition (EMT) has a crucial role in normal and disease processes including tumor progression. In this study, we first classified epithelial-like and mesenchymal-like oral squamous cell carcinoma (OSCC) cell lines based on expression profiles of typical EMT-related genes using a panel of 18 OSCC cell lines. Then, we performed methylation-based and expression-based analyses of components of the Wnt signaling pathway, and identified WNT7A and WNT10A as genes silenced by mesenchymal-specific DNA hypermethylation in OSCCs. A significant association was revealed between some clinicopathological findings and the DNA methylation status of WNT7A (normal vs tumor, P=0.007; T1-2 vs T3-4, P=0.040; I-III vs IV, P=0.016) and WNT10A (N0-N1 vs N2-N3, P=0.046) in the advanced stages of OSCC. Moreover, we found that E-cadherin expression in cancer cells may be positively regulated by WNT7A, whose expression is negatively regulated by mesenchymal-specific DNA hypermethylation or ZEB1 in mesenchymal-like OSCC cells. Our findings indicate that epithelial-specific gene silencing through mesenchymal-specific DNA hypermethylation may stabilize the phenotypic plasticity of cancer cells during EMT/MET.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Carcinoma, Squamous Cell / genetics*
  • Cell Line, Tumor
  • DNA Methylation*
  • Epithelial-Mesenchymal Transition*
  • Female
  • Gene Silencing
  • Humans
  • Male
  • Middle Aged
  • Mouth Neoplasms / genetics*
  • Phenotype
  • Wnt Proteins / genetics
  • Wnt Signaling Pathway*

Substances

  • WNT10A protein, human
  • WNT7A protein, human
  • Wnt Proteins