Ovarian cancer cells grow in response to a variety of growth factors. If proteins that allow a response to a specific growth factor exist on cancer cells but not on normal ovarian epithelial cells, it is possible that these proteins, called receptors, could serve as tumor-specific targets for new therapeutics. Recently, breast cancer cells were shown to have a version of the receptor for the hormone insulin that is different from the metabolically critical insulin receptor. This unique protein, called insulin receptor isoform A, primarily regulates cell growth instead of metabolism. Additionally, unlike the metabolic insulin receptor, isoform A can respond to insulin-like growth factor-II (IGF-II) as well as to insulin. Because IGF-II may be elevated locally in ovarian tumors, it is possible that IGF-II uses the isoform A receptor to control ovarian cancer cell growth.
Dr. Kalli’s laboratory has shown that ovarian cancer cell lines have insulin receptors that control growth. In her project, she will use these cell lines and patient samples to determine the role of the insulin receptor in regulating ovarian cancer growth and tumorigenicity. The results should lead to a better understanding of the biology of ovarian cancer. Additionally, they may identify potential targets for therapeutics that would block the insulin receptor isoform A while sparing the metabolic insulin receptor, vital for metabolism.