Research in ovarian cancer has provided strong support for the “cancer stem cell” hypothesis, which proposes that a rare group of tumor cells have the unique ability to initiate and perpetuate tumor growth. These cancer stem cells can renew themselves (like embryonic stem cells do) and therefore contribute to cancer recurrence. Ovarian cancer stem cells may be highly resistant to chemotherapy; therefore, the development of more effective therapies for ovarian cancer requires effective targeting of stem cells. MicroRNAs are short pieces of single-stranded RNA that control the expression of genes, and which may play roles in cancer stem cell behavior. This research project looks at the role of microRNAs in regulating the “PI-3 kinase pathway,” which is involved in ovarian cancer stem cell proliferation. Dr. Zhang will explore whether the restoration of certain microRNA expressions will shut down the PI-3 kinase pathway and stop cancer cell growth. Such findings might lead to ovarian cancer drugs directed at specific molecules employed by cancer cells to grow.