Abstract 7134: Treatment of pancreatic cancer cells with tumor treating fields (TTFields) and PARP inhibitors

Abstract Background: Therapeutic options for advanced stage pancreatic cancer are limited. Patients harboring germline BRCA mutations benefit from PARP inhibitors (PARPi) ; unfortunately, such mutations are rare in pancreatic cancer. Tumor Treating Fields (TTFields), electric fields that disrupt cellular processes crucial for cancer cell viability, have shown effectiveness against pancreatic cancer cells, and are currently under clinical investigation for the treatment of patients with pancreatic cancer. The mechanism of action of TTFields in various cancer types has suggested involvement of BRCA downregulation. The current study examined the potential sensitization of BRCA wild-type pancreatic cancer cell lines to PARPi with TTFields application. Methods: BxPC3 and AsPC1 human pancreatic BRCA wild-type cancer cells were treated for 72 h with TTFields (frequency of 150 kHz; intensity of 1 and 0. 5 V/cm RMS, respectively), using the inovitro device. The PARPi niraparib and olaparib were each administered to the cells at various concentrations, with or without co-application of TTFields. At treatment cessation, cell count, colony formation, and apoptosis were measured. Results: Applying PARPi to pancreatic cell lines yielded a dose-dependent cytotoxic and anti-clonogenic effects, and induced apoptosis. TTFields application also induced such effects when applied alone, while delivery of TTFields together with PARPi amplified the effects demonstrated by PARPi alone. Conclusions: Concomitant application of TTFields and PARPi in BRCA wild type pancreatic cancer cells exhibits a potential improvement relative to the mono-therapies. This could be rationalized based on the previously demonstrated ability of TTFields to induce a state of BRCAness in cancer cells, and suggests benefit for TTFields and PARPi co-treatment in the absence of background BRCA mutations. Citation Format: Hila Ene, Kerem Ben Meir, Antonia Martinez-Conde, Roni Frechtel-Gerzi, Hila Gabay, Daria Gerasimova, Rotem Engelman, Eyal Dor-On, Adi Haber, Moshe Giladi, Yoram Palti. Treatment of pancreatic cancer cells with tumor treating fields (TTFields) and PARP inhibitors abstract. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts) ; 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84 (6Suppl): Abstract nr 7134.