Grant: Doctoral Research Award: Canada Graduate Scholarships

Among gynecological cancers, ovarian cancer is the leading cause of death in women. The most common and lethal type is high-grade serous ovarian cancer (HGSC), for which the five-year survival rate is 45%. The standard treatment for patients is surgery to remove the bulk of the tumor and chemotherapy to kill the remaining cells, often with the drugs carboplatin and paclitaxel. Although many patients initially respond well to the treatment, approximately 70% of patients will develop resistance to the chemotherapy. The molecular and behavioural properties of cancer cells within tumours can vary. Our lab has identified three distinct types of cancer cells in HGSC, named SecA, SecB and Cil. We found that there were more SecB cells in both tumors that have spread and chemotherapy-treated tumors, suggesting the group of SecB cells is associated with disease spread and resistance to the treatments. Traditional strategies to study chemotherapy resistance involve continuous exposure of cells to the drugs until the cells are no longer affected. However, this method does not recapitulate how patients receive treatment in the clinic, where they are given single doses of chemotherapy every 3 weeks for 6 cycles. As such, there is a critical need to study treatment resistance using clinically relevant therapy regimens. Therefore, we aim to evaluate the response of the different cancer cell populations throughout cyclic chemotherapy treatment. We hypothesize that the group of SecB cells will expand following each treatment cycle and that targeting these specific cells could prevent resistance against the chemotherapy drugs. Overall, this project aims to understand how cells tolerate treatment and to determine strategies to target this group of cells so that resistance to chemotherapy does not develop.