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Updated: Jun 2, 2026

Studying TGF-β Signaling and TGF-β-induced Epithelial-to-mesenchymal Transition in Breast Cancer and Normal Cells
06:54

Studying TGF-β Signaling and TGF-β-induced Epithelial-to-mesenchymal Transition in Breast Cancer and Normal Cells

Published on: October 27, 2020

HSP70 decreases receptor-dependent phosphorylation of Smad2 and blocks TGF-β-induced epithelial-mesenchymal

Yihao Li1, Xianjiang Kang, Qiang Wang

  • 1College of Life Sciences, Hebei University, Baoding 071002, China.

Journal of Genetics and Genomics = Yi Chuan Xue Bao
|April 12, 2011
PubMed

Insights

Heat shock protein 70 (HSP70) inhibits transforming growth factor beta (TGF-β) signaling by preventing Smad2 phosphorylation. This interaction blocks TGF-β-induced epithelial-mesenchymal transition (EMT), revealing HSP70

Area of Science:

  • Cellular signaling pathways
  • Molecular biology
  • Protein interactions

Background:

  • Transforming growth factor beta (TGF-β) signaling is crucial for cellular processes.
  • Smad2 and Smad3 are key intracellular mediators of TGF-β signaling.
  • TGF-β signaling regulates gene expression via Smad protein nuclear translocation.

Purpose of the Study:

  • To investigate the role of 70-kDa heat-shock protein (HSP70) in TGF-β signal transduction.
  • To determine if HSP70 affects Smad2 phosphorylation and nuclear translocation.
  • To elucidate the impact of HSP70 on TGF-β-induced epithelial-mesenchymal transition (EMT).

Main Methods:

  • Investigated the interaction between HSP70 and Smad2.
  • Assessed the effect of HSP70 on TGF-β receptor-dependent Smad2 phosphorylation.
  • Monitored Smad2 nuclear translocation in response to TGF-β.
  • Examined the influence of HSP70 on TGF-β-induced EMT in HaCat cells.

Main Results:

  • HSP70 directly interacts with Smad2.
  • HSP70 expression decreases TGF-β signal transduction.
  • Ectopic HSP70 expression prevents Smad2 phosphorylation and nuclear translocation.
  • HSP70 blocks TGF-β-induced EMT in HaCat cells.

Conclusions:

  • HSP70 plays a critical role in regulating TGF-β signaling.
  • HSP70 acts as an inhibitor of TGF-β-induced EMT.
  • HSP70 impedes TGF-β signaling by blocking Smad2 phosphorylation.

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