TGF-beta signaling: a tale of two responses

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Updated: Jul 12, 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

Rod A Rahimi1, Edward B Leof

  • 1Department of Biochemistry and Molecular Biology, Thoracic Diseases Research Unit, Mayo Clinic Cancer Center, Mayo Clinic College of Medicine, Rochester, Minnesota 55905, USA.

Journal of Cellular Biochemistry
|August 31, 2007
PubMed

Insights

Transforming growth factor-beta (TGF-beta) signaling exhibits versatile cellular effects, from growth arrest to promoting cancer. This review explores how Smad and non-Smad pathways explain TGF-beta

Area of Science:

  • Molecular Biology
  • Cell Signaling
  • Cancer Biology

Background:

  • Transforming growth factor-beta (TGF-beta) is a crucial regulator of diverse cellular functions, including cell growth, apoptosis, differentiation, migration, and extracellular matrix production.
  • The canonical TGF-beta pathway involves Smad protein phosphorylation, nuclear translocation, and transcriptional regulation.
  • Cellular responses to TGF-beta are highly context-dependent, with epithelial cells undergoing growth arrest and apoptosis, while fibroblasts are activated, and epithelial cells can undergo epithelial-mesenchymal transition.

Purpose of the Study:

  • To review TGF-beta signaling in epithelial cells and fibroblasts.
  • To elucidate the mechanisms underlying TGF-beta's versatile cellular responses.
  • To understand how Smad and non-Smad pathways collaborate to determine cellular phenotype.

Main Methods:

  • Literature review of TGF-beta signaling pathways.
  • Analysis of Smad and non-Smad signaling interactions.
  • Focus on TGF-beta's role in epithelial cells and fibroblasts.

Main Results:

  • TGF-beta elicits opposing cellular outcomes (e.g., tumor suppression vs. cancer promotion) through the same receptor complex and Smad proteins.
  • Emerging evidence highlights the involvement of non-Smad pathways in modulating TGF-beta's diverse effects.
  • The interplay between Smad and non-Smad pathways dictates specific cellular phenotypes in response to TGF-beta.

Conclusions:

  • The paradox of TGF-beta's varied cellular effects is explained by the integration of Smad and non-Smad signaling.
  • Understanding these collaborative pathways is key to deciphering TGF-beta's role in physiological and pathological processes.
  • This review provides insights into the complex mechanisms governing TGF-beta signaling versatility.

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