Abstract 5657: Carbon monoxide-releasing molecules as top-notch candidates for prostate cancer therapy

Abstract Carbon monoxide (CO) is an endogenous gasotransmitter with proven anti-inflammatory, anti-apoptotic, and antiproliferative effects. CO-releasing molecules (CO-RMs) have been developed to deliver controlled doses of CO, differing in their CO-release kinetics and chemical structure, showing promise as therapeutic agents in various diseases, including cancer. The main goal of our study is to identify the effectiveness of CO-RMs as a therapeutic strategy to counteract prostatic carcinogenesis. This study aimed to assess the effects of three water-soluble CO-RMs—CORM-3, CORM-401, and CORM-A1—on key hallmarks of prostate cancer (PCa). Using the PCa cell line PC3 we evaluated cell viability across a range of CO-RM concentrations (25-150 µM; 6 h) to identify doses that do not compromise cell viability for further analyses. Confocal microscopy with the DCFH-DA probe revealed that CO-RM treatments significantly reduced reactive oxygen species (ROS) levels (p<0.001). Furthermore, CO-RMs enhanced cell adhesion (p<0.001) and inhibited cell migration (p<0.01). Moreover, mitochondrial integrity, mitochondrial mass and mitochondrial DNA copy numbers were significantly altered (p<0.0001), as shown by MitoGreen, TMRE staining and RT-qPCR. Metabolically, PC3 cells treated with CO-RMs exhibited significant reductions in ATP content (p<0.05), LDH activity (p<0.01) and lactate amounts (p<0.01). At the molecular level, CO-RMs repressed markers of oxidative stress (NFkB, SOD-2), metabolism (PKM2, PDHB, ACO2), proliferation (Ki67) (p<0.01) and angiogenesis (VEGF) (p<0.05), as assessed by RT-qPCR. Additionally, analyzing stem-like characteristics, we observed that CO-RMs reduced spheroid size in a hanging drop assay (p<0.0001), as well as colony formation in a clonogenic assay (p<0.01). As PCa predominantly metastasizes to bone, we further analyzed the potential of CO-RMs to modulate the communication between tumor and bone cells using indirect co-cultures of PC3 cells with osteoblasts precursor cells (MC3T3). CO-RMs decreased osteoblastic marker levels in bone cells (COL1A1, SPP1, RUNX2) (p<0.01) and increased OPG expression in PCa cells (p<0.01) demonstrating that this molecule impaired the crosstalk between both cell types, probably affecting the osteotropism of PC3 cells. This study demonstrates that CO-RMs has a strong effect on modulating key biological processes in PCa cells, highlighting its potential as a therapeutic agent for PCa. Citation Format: Gastón Pascual, Pablo Sanchis, Agustina Sabater, Rocio Seniuk, Javier Cotignola, Elba Vazquez, Ayelen Toro, Roberta Foresti, Roberto Motterlini, Geraldine Gueron. Carbon monoxide-releasing molecules as top-notch candidates for prostate cancer therapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 5657.