Ovarian cancer is the fifth leading cause of cancer deaths overall in women. The most recent estimates indicate that over 20,000 new cases will be diagnosed this year and nearly 14,000 women will die of the disease in the US in 2019 alone. The platinum-based standard of care cytotoxic regimen has remained largely stagnant for the last 15 years and recurrent disease is frequently platinum-resistant. Despite some recent success using molecular targeted agents and maintenance therapies (such as PARP inhibitors), the genetic complexity and lack of common molecular drivers make predicting patient responses difficult. Additionally, in relapsed patients, molecular changes induced by cancer therapies are multifaceted. Combining multiple drugs to treat ovarian cancer may be the most direct path to overcoming this intra-tumoral heterogeneity and acquired resistance to achieve more durable clinical responses. In an effort to capitalize on drugs that are approved and show patient benefit, this proposal seeks to identify compounds that can sensitize cells to apoptosis when combined with one of three drugs that act as cornerstones in ovarian cancer therapy: carboplatin, the PARP inhibitor olaparib, and doxorubicin. In the first aim a novel high-throughput screening platform called high-throughput dynamic BH3 profiling, will be used to identify whether a 24-hour ex vivo chemical treatment sensitizes tumor cells to mitochondrial mediated apoptosis. This will be performed using three ovarian cancer models: (1) freshly isolated tumor cells from primary patient ascites fluid, (2) organoid cultures derived from primary tumors, and (3) ovarian tumor cell lines. Preliminary data indicates that BH3 mimetics in combination with the standard of care drugs can increase apoptotic induction. In the second aim, the mechanism of drug-induced BH3 mimetic sensitivity will be investigated on the cellular, mitochondrial, and molecular level to determine which cellular contexts are likely to benefit from specific BH3 mimetic combinations. In the third and final aim compounds identified that increase apoptotic induction in combination with each of the three standard of care drugs will be tested in recently developed patient-derived luciferized tumor xenograft models of ovarian cancer. This will provide in vivo validation of the ability of specific drug combinations to cause tumor regression. This innovative approach offers both the potential to identify effective combinations to use in the platinum-sensitive, PARP-sensitive, and platinum-resistant settings, and the opportunity to determine molecular features that can identify populations that would benefit from these combinations. Supplementing the research component of the proposal with select courses and workshops, engagement in research meetings and seminars, and participation in scientific conferences will ensure an understanding of current concepts and techniques, constant feedback regarding the project's results and progress, and enhanced exposure to more translational work. Collectively, the research and training plan will provide a strong foundation upon which to build a career as a productive, independent cancer researcher.
Ovarian cancer is the leading cause of gynecologic cancer-related death in the United States and is frequently diagnosed at an advanced stage. These statistics highlight the unmet need to develop new approaches to treating ovarian cancer; a void that could be filled by combining therapies to increase the efficacy and probability of a therapeutic response in a heterogenous tumor environment. The aim of this project is to identify drug combinations and understand how we can exploit specific vulnerabilities using patient samples and relevant models, thus providing a novel pharmacological strategy to employ in the treatment of patients affected by ovarian cancer.
