Peptide-Based Inhibitors of Neu Tyrosine Kinase
Abstract
This project focuses on the product of the HER2/Neu oncogene, a receptor tyrosine kinase that is amplified in 25-30% of human primary breast tumors. The overall goal of the project is to characterize the substrate specificity 0 one HER2/Neu kinase. In previous years, we expressed and purified HER2/Neu using the SfO,baculovirus system. We then used peptide library technology to isolate novel peptide substrates for HER/Neu. One of them, AAEEIYAARRG, is the best synthetic peptide substrate reported to date for HER2/Neu. In the final year of the project, we produced several potential peptide-based inhibitors for HER2/Neu by replacing the tyrosine residue in the substrate peptide with the following amino acid analogs: (1) p-L-carboxy-Phe; (2) p-D-carboxy-Phe; (3) tetrafluoro-L-Phe; (4) tetrafluoro-D-Phe; (5) 3,5-diiodo-L-Phe. We produced an additional peptide inhibitor by introducing p-L-carboxy-Phe into another peptide isolated from the library (EDKVDYRMHRRG) The inhibitory potencies of these compounds against purified HER2/Neu were in the millimolar range; these values were too high for in vivo Inhibition of HER2/Neu. Instead, we used a microinjection technique to measure the ability of the parent peptide AAEEIYAARRG to block EGF-induced membrane ruffling in a fibroblast model system. The peptide showed significant inhibition of the EGF effect.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 2000
- Accession Number
- ADA387606
Entities
People
- W. T. Miller
Organizations
- State University of New York