Abstract 1589: Morin activates mitophagy via the PINK1/Parkin pathway, promoting apoptosis and suppressing tumor growth in pancreatic cancer cells

Abstract Background: Pancreatic cancer (PC) is an aggressive malignancy characterized by high rates of invasiveness, chemoresistance, and relapse. Mitochondrial dysfunction, often due to mutations or metabolic imbalances, results in excessive ROS production and DNA damage, enhancing tumor aggressiveness. Additionally, stromal fibrosis in PC hinders drug delivery, complicating treatment outcomes. Therefore, we aim to investigate the effect of Morin, a bioflavonoid with antioxidant and anti-inflammatory properties, in promoting mitophagy in PC cells to inhibit tumor progression. Methods: Experiments were conducted under control and Morin-treated conditions on PANC-1 cells and normal pancreatic epithelial cells. Cytotoxicity was assessed via the MTT assay, while invasiveness, migration, morphology, and stemness were evaluated using colony-formation, transwell, spheroid-formation assays, and ALDH activity. Mitochondrial membrane potential, functional mitochondria, superoxide production, and ROS were analyzed using JC-1, Mitotracker Green/Red, MitoSOX™ Red, and DCFDA dyes. Apoptosis was quantified with Annexin V/PI staining, and ATP synthase activity was measured using ATP Synthase Profiling Kit. Expression of markers related to mitochondrial function, transport, and apoptosis was analyzed via PCR microarray, qRT-PCR, and immunofluorescence. Results: Morin exhibited a dose- and time-dependent cytotoxic effect on PANC-1 cells, with an IC50 of 50.018 µM at 24 hours. Treatment reduced spheroid size, made them rounder, and formed pores, indicating apoptosis. Morin also decreased colony formation, migration, and ALDH activity, suggesting reduced cancer stem cell properties. JC-1 staining showed a lower mitochondrial membrane potential, while DCFDA indicated reduced ROS, and MitoSOX Red revealed increased superoxide levels. Mitotracker Red/Green staining indicated fewer dysfunctional mitochondria. Following Morin treatment, Annexin V/PI staining showed significant increases in apoptosis and reduced ATP synthase activity (p = 0.0286). Microarray results indicated significant downregulation of genes related to mitochondrial fusion (MFN2, p = 0.000616), and apoptosis regulator (SH3GLB1, p = 0.037). qRT-PCR and immunofluorescence showed Morin upregulated mitophagy genes (PINK1, Parkin), autophagy markers (LC3b), and apoptosis markers (Cytochrome c), while increasing epithelial markers (E-Cadherin) and decreasing mesenchymal (N-Cadherin, Snail, ZEB1), and stemness markers (Sox2, Nanog, OCT4). In silico docking showed stable binding of Morin to mitophagy marker PINK1 (docking score: -8.3 kcal/mol). Conclusion: Morin targets mitochondrial dysfunction via the PINK1/Parkin pathway, promoting apoptosis and reducing cancer cell survival, highlighting its promise as a potential therapeutic agent. Citation Format: Vinit Sharma, Mayank Sharma, Ankita Semwal, Ankita Arora, Sakshi Bansal, Anjali Aggarwal. Morin activates mitophagy via the PINK1/Parkin pathway, promoting apoptosis and suppressing tumor growth in pancreatic cancer cells [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 1589.