Abstract 4488: Newly developed organoiridium(III) complexes containing N,P-ligands possess antiproliferative activity in selected cancer cell lines

Abstract

Abstract In conventional cancer treatment, platinum-based cytostatics are considered as standard therapy; however, they possess severe side effects. This fact leads to a constant effort to develop new non-platinum metallodrugs with different mechanism of action (MoA). In our study we developed new half-sandwich organoiridium(III) complexes, of general formulas [Ir(η5-Cp*)Cl(LNP)]PF6 (1-3) and [Ir(η5-Cpph)Cl(LNP)]PF6 (4-6) involving three different N,P-donor phosphinoalkylamines (LNP), which we tested on 2D and 3D cancer models; HCp* = pentamethylcyclopentadiene, HCpph= (2,3,4,5-tetramethylcyclopenta-2,4-dien-1-yl)benzene. The most effective complexes 3 and 6 bearing 3-(diphenylphosphanyl)propan-1-amine had the highest cytotoxic effect against various cancer cell lines (THP-1, HeLa, SW982, A549, MOR) including a cisplatin-resistant lung carcinoma cell line (MOR/CPR) with IC50 values between 3.1 and 9.1 μM for specific cell lines. The cytotoxic effect was further demonstrated on 3D spheroids of lung cancer cells that revealed anti-cancer and anti-migration potential of complexes 3 and 6. Cell cycle and cell death analysis showed a different mechanism compared to the effect of cisplatin. Moreover, complex 3 did not decrease cell viability of non-cancerous cells (peripheral blood mononuclear cells and porcine chondrocytes) under 50% at a concentration of 20 µM. In addition, we report for the first time that organoiridium complexes showed high cytotoxic activity on cancer cell lines, including cisplatin-resistant cell line, with different MoA from cisplatin. They trigger expression of stress-related genes associated with oxidative stress, DNA damage, and endoplasmic reticulum stress and, moreover, complex 3 showed cytotoxic selectivity towards cancer cells. This work was supported by the Czech health research council of the Ministry of Health of the Czech Republic (AZV Project NU22-08-00236). Citation Format: Renata Hezova, Jan Hosek, Nicol Strakova, Pavlina Simeckova, Josef Masek, Simona Kajabova, Pavel Starcha. Newly developed organoiridium(III) complexes containing N,P-ligands possess antiproliferative activity in selected cancer cell lines [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(6_Suppl):Abstract nr 4488.