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Screening and Identification of Small Peptides Targeting Fibroblast Growth Factor Receptor2 using a Phage Display Peptide Library
Published on: September 30, 2019
Epidermal growth factor receptor downregulation by small heterodimeric binding proteins
Benjamin J Hackel1, Jason R Neil, Forest M White
1Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
Protein Engineering, Design & Selection : PEDS
|December 14, 2011
Summary
Researchers engineered novel protein domains that effectively reduce epidermal growth factor receptor (EGFR) levels by up to 80% in cancer cells. These small protein heterodimers offer a new approach for targeting cancer by modulating surface receptors.
Area of Science:
- Biotechnology
- Molecular Biology
- Cancer Research
Background:
- Epidermal Growth Factor Receptor (EGFR) is a key target in cancer therapy.
- Existing methods have limitations in robustly downregulating EGFR.
Purpose of the Study:
- To engineer novel protein domains capable of downregulating EGFR.
- To evaluate the efficacy of these engineered proteins in reducing EGFR levels and inhibiting cancer cell activities.
Main Methods:
- Engineering fibronectin-based protein domains with high affinity for multiple EGFR epitopes.
- Constructing monovalent and bivalent dimers of these domains.
- Testing domain dimers for EGFR downregulation, signaling inhibition, and effects on cell proliferation and migration.
Main Results:
- Selected non-competitive heterodimers achieved up to 80% decrease in EGFR levels across various cell types.
- Engineered heterodimers inhibited EGFR autophosphorylation, cell proliferation, and migration without activating signaling.
- These heterodimers demonstrated synergy with cetuximab in inhibiting cancer cell activities.
Conclusions:
- Small (25 kDa) engineered protein heterodimers represent a novel and effective modality for modulating surface receptor levels.
- This approach offers a promising new strategy for cancer therapy by targeting EGFR.
- The developed heterodimers show potential for combination therapy with existing treatments like cetuximab.
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