Abstract 5180: Nuclear receptor tyrosine kinase c-MET restrains efficacy of PARP inhibitor in pancreatic cancer cells

Abstract

Abstract Pancreatic tumors commonly have intra-tumor hypoxia and high reactive oxygen species (ROS) production and have become the fourth leading cause of death in the United States. Although ROS leads to oxidation of macromolecules such as DNA, protein, and lipids, pancreatic cancer cells are capable of surviving from the ROS-induced stress at relatively high tolerable levels. Therefore, identifying potential molecular mechanisms for pancreatic cancer cells to overcome ROS-induced cellular stress is important for develop therapeutic strategies in treating pancreatic cancer patients. While poly (ADP-ribose) polymerase 1 (PARP1) is a key protein for repairing ROS-induced DNA damages, we intended to include PARP inhibitors in targeted therapy strategy. Recent clinical trial showed that PARP inhibitor benefits pancreatic patients with BRCA mutation. However, our goal is to expand PARP inhibitor targeted therapy to pancreatic cancer patients without BRCA mutation with PARP inhibitor using strategies of combining kinase inhibitors as we demonstrated in breast cancer in our previous publications. Here, we used hydrogen peroxide (H2O2) as ROS stimuli and demonstrated that H2O2 induces nuclear transport of the receptor tyrosine kinase c-MET in AsPC-1 and BxPC-3 pancreatic cancer cells. We further showed that nuclear-located c-MET interacts with PARP1, and the interaction can be partially interrupted by crizotinib, a kinase inhibitor targeting c-MET. Moreover, combination of crizotinib and PARP inhibitor, olaparib, has synergistic anti-tumor effect in eliminating pancreatic cancer cells. Our data suggest that the intra-tumor hypoxia micro-environment of pancreatic cancer may promote nuclear localization of c-MET, which results in resistance to PARP inhibitor therapy. We further proposed a new therapeutic strategy of combining c-MET inhibitors and PARP inhibitors for advanced pancreatic cancer patients. Citation Format: Yuan Gao, Mei-Kuang Chen, Dihua Yu, Mien-Chie Hung. Nuclear receptor tyrosine kinase c-MET restrains efficacy of PARP inhibitor in pancreatic cancer cells [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 5180.