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Updated: May 17, 2026

Studying TGF-β Signaling and TGF-β-induced Epithelial-to-mesenchymal Transition in Breast Cancer and Normal Cells
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A transcriptionally active pRb-E2F1-P/CAF signaling pathway is central to TGFβ-mediated apoptosis

J Korah1, N Falah, A Lacerte

  • 1Division of Medical Oncology, Department of Medicine, McGill University Health Center, Montreal, Canada.

Cell Death & Disease
|October 13, 2012
PubMed

Insights

Transforming growth factor-β (TGFβ) induces apoptosis via the transcription factor E2F1. This study reveals TGFβ stabilizes E2F1 protein, leading to cell death in both cancer and normal cells.

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Cancer Research

Background:

  • Transforming growth factor-β (TGFβ) is known to regulate apoptosis, but the central downstream signaling pathway remains unclear.
  • Identifying key mediators of TGFβ-induced cell death is crucial for understanding cancer progression and developing therapeutic strategies.

Purpose of the Study:

  • To elucidate the central signaling pathway downstream of TGFβ that mediates apoptosis.
  • To identify the role of transcription factor E2F1 in TGFβ-induced cell death.

Main Methods:

  • Utilized E2F1 knockout mouse models to assess TGFβ-mediated apoptosis in normal and cancer cells.
  • Investigated the post-translational regulation of E2F1 by TGFβ.
  • Analyzed the formation of E2F1-containing transcription complexes on target gene promoters.

Main Results:

  • TGFβ-induced apoptosis requires the transcription factor E2F1 in both cancer and normal cells.
  • TGFβ enhances E2F1 protein stability at the post-translational level.
  • TGFβ promotes the formation of a transcriptionally active E2F1-pRb-P/CAF complex on pro-apoptotic gene promoters, activating their transcription.

Conclusions:

  • E2F1 is a central mediator of the TGFβ apoptotic program.
  • The TGFβ-E2F1 signaling axis represents a novel mechanism for gene activation leading to apoptosis.

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