The investigators hypothesize that a complex combination of regulatory mechanisms is responsible for the low level of EGFR expression in ER+ breast cancer cells and that alterations in these mechanisms results in EGFR up- regulation during the progression to hormone-independence, and ultimately the overexpression of EGFR in ER- breast cancer cells. Using the available molecular biological techniques and the resources of the Lombardi Cancer Center, the investigators proposed to study three specific aims: 1) to determine the mechanisms by which low basallevels of EGFR are maintained in ER+ breast cancer cells, 2) to determine the mechanisms by which overexpression of EGFR occurs in ER- breast cancer cells and 3) to define the role of EGFR in the progression of breast cancer to hormone-independence. The results of the study may provide a specific target for the treatment and prevention of hormone-independent breast cancer.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Research Project (R01)
Project #
5R01CA055677-06
Application #
2517565
Study Section
Reproductive Endocrinology Study Section (REN)
Project Start
1992-09-01
Project End
1998-08-31
Budget Start
1997-09-01
Budget End
1998-08-31
Support Year
6
Fiscal Year
1997
Total Cost
Indirect Cost
Name
Georgetown University
Department
Internal Medicine/Medicine
Type
Schools of Medicine
DUNS #
049515844
City
Washington
State
DC
Country
United States
Zip Code
20057
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Chrysogelos, S A; Dickson, R B (1994) EGF receptor expression, regulation, and function in breast cancer. Breast Cancer Res Treat 29:29-40
Chrysogelos, S A (1993) Chromatin structure of the EGFR gene suggests a role for intron 1 sequences in its regulation in breast cancer cells. Nucleic Acids Res 21:5736-41