Related Experiment Video

Updated: Jul 5, 2026

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

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Published on: October 27, 2020

Rb/E2F4 and Smad2/3 link survivin to TGF-beta-induced apoptosis and tumor progression

J Yang1, K Song, T L Krebs

  • 1Division of General Medical Sciences-Oncology, Case School of Medicine, Case Western Reserve University, Cleveland, OH 44106, USA

Oncogene
|May 28, 2008
PubMed

Insights

Transforming growth factor-beta (TGF-beta) rapidly reduces survivin protein levels in prostate cells. This newly found TGF-beta/Rb/survivin pathway impacts cancer progression and treatment resistance.

Area of Science:

  • Molecular Biology
  • Cancer Biology
  • Cell Signaling

Background:

  • Survivin is a key protein promoting cancer cell survival and drug resistance.
  • Mechanisms regulating survivin expression in cancer are not fully understood.
  • Transforming growth factor-beta (TGF-beta) plays a complex role in cancer, acting as both a suppressor and promoter.

Purpose of the Study:

  • To investigate the role of survivin in TGF-beta-induced apoptosis.
  • To elucidate the molecular mechanisms by which TGF-beta regulates survivin expression.
  • To explore the potential therapeutic implications of the TGF-beta-survivin interaction.

Main Methods:

  • Analysis of survivin expression in prostate epithelial cells.
  • Investigating transcriptional regulation involving Smad proteins, Rb/E2F4, and promoter elements (CDE/CHR).
  • Utilizing viral-mediated gene delivery for survivin overexpression and silencing.

Main Results:

  • TGF-beta rapidly downregulates survivin expression via transcriptional suppression.
  • The mechanism involves Smad2/3-dependent Rb hypophosphorylation and Rb/E2F4 complex binding to the survivin promoter.
  • Survivin plays a critical role in TGF-beta-induced apoptosis, alone or with chemotherapeutics.

Conclusions:

  • A novel TGF-beta/Rb/survivin signaling axis is identified.
  • This pathway is crucial for regulating apoptosis in response to TGF-beta.
  • The findings suggest a role for this axis in TGF-beta's switch from tumor suppressor to promoter in cancer.

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