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Updated: Jul 20, 2026
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
Prion protein modifies TGF-beta induced signal transduction
Susanne Wurm1, Christian Wechselberger
1Upper Austrian Research GmbH, Center for Biomedical Nanotechnology, 4020 Linz, Austria.
Biochemical and Biophysical Research Communications
|September 1, 2006
Summary
Over-expression of cellular prion protein enhances transforming growth factor-beta (TGF-beta) signaling, increasing matrix metalloproteinase-2 (MMP-2) activity. This impacts cell adhesion and tissue development, suggesting a role in cancer metastasis.
Area of Science:
- Cell Biology
- Molecular Biology
- Biochemistry
Background:
- Transforming growth factor-beta (TGF-beta) superfamily proteins regulate critical cellular functions and extracellular matrix protein expression.
- Matrix metalloproteinases (MMPs) are enzymes that degrade extracellular matrix components, playing roles in development and disease.
- MMPs are implicated in pathological conditions including cancer metastasis and impaired wound healing.
Purpose of the Study:
- To investigate the effect of cellular prion protein (PrP) over-expression on TGF-beta-induced signaling pathways.
- To determine the impact of PrP on the activity and expression of MMPs, specifically MMP-2.
- To assess the functional consequences of PrP modulation on epithelial cell behavior, including adhesion and morphogenesis.
Main Methods:
- Over-expression of cellular prion protein in mouse mammary gland epithelial cells.
- Stimulation with transforming growth factor-beta (TGF-beta).
- Measurement of secreted MMP-2 activity using enzymatic assays.
- Assessment of cell-substrate adhesion in epithelial monolayers.
- Analysis of cell morphogenesis in three-dimensional collagen matrices.
Main Results:
- Cellular prion protein over-expression synergistically enhanced TGF-beta-induced MMP-2 activity.
- Elevated MMP-2 activity correlated with increased substrate detachment of epithelial cells.
- Morphogenesis of epithelial cells in a three-dimensional collagen type I matrix was disrupted.
Conclusions:
- Cellular prion protein modulates TGF-beta signaling to increase MMP-2 activity.
- Enhanced MMP-2 activity driven by PrP contributes to altered cell adhesion and impaired tissue development.
- These findings suggest a potential role for PrP in cancer progression and metastasis through MMP regulation.
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