The BHLH transcription factor DEC1 plays an important role in the epithelial-mesenchymal transition of pancreatic cancer

Int J Oncol. 2012 Oct;41(4):1337-46. doi: 10.3892/ijo.2012.1559. Epub 2012 Jul 18.


DEC1 (BHLHE40/Stra13/Sharp2) is a basic helix-loop-helix (bHLH) transcription factor that is involved in the regulation of apoptosis and cell proliferation and the response to hypoxia. Epithelial-mesenchymal transition (EMT) is an important step leading to invasion and migration of various tumor cells, and TGF-β treatment has been shown to induce cancer cells to undergo EMT. However, the significance of DEC1 in TGF-β-induced EMT remains unknown. We examined the role of DEC1 in EMT of PANC-1 cells, a human pancreatic cancer cell line. As a result, we found that DEC1 was upregulated by TGF-β in PANC-1 cells, and regulated the expression and the levels of nuclear, cytoplasmic or membrane localization of EMT-related factors, including phosphorylated Smad3 (pSmad3), snail, claudin-4 and N-cadherin. In the presence of TGF-β, DEC1 knockdown by siRNA inhibited morphological changes during EMT processes, while TGF-β induced PANC-1 cells to taken on a spindle-shaped morphology. Furthermore, a combination treatment of DEC1 expression with TGF-β was closely linked to the migration and invasion of PANC-1 cells. Immunohistochemically, DEC1 and pSmad3 were detected within pancreatic cancer tissues, whereas claudin-4 expression was weaker in the cancer tissues compared with the adjacent non-cancer pancreatic tissues. These findings suggest that DEC1 plays an important role in the regulation of these EMT-related factors in pancreatic cancer.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Apoptosis
  • Cell Line, Tumor
  • Cell Movement
  • Cell Proliferation
  • Claudin-4 / metabolism
  • Epithelial-Mesenchymal Transition / genetics*
  • Gene Expression Regulation, Neoplastic
  • Humans
  • Pancreatic Neoplasms / genetics*
  • Pancreatic Neoplasms / metabolism*
  • Pancreatic Neoplasms / pathology
  • RNA, Small Interfering / genetics
  • Smad3 Protein / metabolism
  • Transforming Growth Factor beta / genetics
  • Transforming Growth Factor beta / metabolism
  • Tumor Suppressor Proteins / biosynthesis
  • Tumor Suppressor Proteins / genetics*


  • Claudin-4
  • DELEC1 protein, human
  • RNA, Small Interfering
  • SMAD3 protein, human
  • Smad3 Protein
  • Transforming Growth Factor beta
  • Tumor Suppressor Proteins