Structural Basis of EGFR Dimerization for Drug Design
Abstract
Breast cancer occurs when there is a transition from normal breast epithelial cell behavior to that of uncontrolled cell growth. Cell surface receptors and specific growth factors play a crucial role in this transition. For this project, we proposed to evaluate the role of the epidermal growth factor receptor (EGFR) in breast cancer by expressing and purifying EGFR and solving the atomic structure. Antibodies generated from phage libraries would be used to: 1) facilitate structure solution, and 2) deliver drugs to EGFR expressing cells, EGFR was expressed at high levels and purified to homogeneity, but diffraction quality crystals were never obtained. As a result, efforts focused on antibody generation. A large panel (33) of human scFv antibodies to EGFR were isolated by selection on purified recombinant EGFR or on cells expressing EGFR. For cell selections, a method was developed which allowed direct selection from phage libraries of antibodies which trigger receptor mediated endocytosis. We show that this approach can be used either on tumor cell lines which overexpress the receptor or on cells transfected with the EGFR gene. This permits use of this methodology on transfected cells and provides a means of making antibodies without the need for protein expression and purification. We show that internalizing EGFR antibodies can be used to deliver cytotxic agents into the cytosol of EGFR expressing tumor cells by construction of immunoliposomes bearing an EGFR antibody on their surface. We are in the process of constructing and evaluating such an agent for breast cancer therapy.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 2000
- Accession Number
- ADA396724
Entities
People
- James Marks
Organizations
- University of California Regents