Abstract 7563: Efficacy of JPI-547, novel dual PARP inhibitor, in endometrial cancer cell line

Abstract Objectives: PARP inhibitor is effective in treating DNA repair deficiency endometrial cancer. Endometrial cancer (EC) is one of the most common gynecological cancers in developed countries and its incidence is increasing, and the prognosis of patients with early stage and low-risk EC is very good, but the prognosis of progressive and recurrent EC is poor. Novel PARP inhibitor JPI-547 is a PARP and tankyrase dual inhibitor, and in cancer cells, tankyrase inhibitor plays an important role in DNA repair, telomere maintenance, and cell survival. This experiment was conducted to determine whether the reactivity of the PTEN mutant EEC was increased by using the Novel PARP inhibitor. Method: Human endometrioid endometrial cancer cell lines, Hec-1A, Hec-1B and Ishikawa were obtained. Cell viability assay for the drugs Olaparib and JPI-547 were assessed. Colonies consisting of at least 50 cells were counted. The number of dead cells was counted in five different areas of the hemocytometer, and the experiment was performed three times. The percentage of dead cells was analyzed compared to the untreated group. We confirmed the efficacy by siRNA transfection and immunofluorescence. Result: When treated with Olaparib, there was no change in cell viability in the rest of the cells except for Ishikawa cells, which are PTEN mutations. It decreased by 35. 4% in Ishikawa cells, whereas when treated with JPI-547, all cell lines Hec-1A, Hec-1B, and Ishikawa cell viability decreased by 28%, 34. 3%, and 48. 7%, respectively. PTEN knock-down reduced cell visibility by 28% when treated with olaparib, whereas when treated with JPI-547, Hec-1A (siCont) and Hec-1A (siPTEN) decreased by 26% and 42%, respectively, in all cells regardless of whether PTEN knock-down is present. When treated with Olaparib, dead cells were identified only in PTEN knock-down cells, increasing by 22%. When treated with JPI-547, dead cells increased by 25. 5% and 33% in all cells of Hec-1A (siCont) and Hec-1A (siPTEN), respectively. It was confirmed that JPI-547 can reduce cell viability regardless of the formation of Rad51 according to PTEN. Conclusion: JPI-547, a novel PARP inhibitor, showed good efficacy in PTEN mutation and PTEN-wild-type EEC cell lines than in conventional PARP inhibitor. The effect of reducing survival of ECC cell line with JPI-547 was confirmed with or without PTEN mutation. Further evaluation and in vivo experiments are needed to prove the efficacy of JPI-547 in EC. Citation Format: Shin-Wha Lee, So-Hyun Nam, Su-Bin Park. Efficacy of JPI-547, novel dual PARP inhibitor, in endometrial cancer cell line 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 7563.