Resveratrol Induces Oxidative Stress and Downregulates GPX4 and xCT to Activate the Ferroptosis Pathway for Anti-Bladder Cancer Organoids.

Purpose: Resveratrol (RES) exhibits promising anti-bladder cancer (BC) effects. It causes cell death of BC cell lines and xenografts, but comprehensive analyses are required concerning oxidative status in RES-treated BC cells and its relevance with cell death patterns, and especially the efficacy of BC individuals. Methods: Two human BC cell lines (T24 and UM-UC-3) were cultured under 2D and 3D conditions to determine RES IC₅₀ values and 100 μM RES was thus used as a working concentration to treat 18 cases of BC-derived organoids (BCDOs). To observe the experimental results, this study will assess the oxidative stress status of bladder cancer cells, the corresponding potential cell death patterns, and the extent of inhibition by death inhibitors. Results: It revealed growth suppression of 10 RES-treated BCDOs (55.56%), accompanied by reduced mitochondrial potential and increased Reactive Oxygen Species (ROS) levels. Lipid peroxidation and downregulation of GPX4 and xCT, key antioxidant molecules of ferroptosis, were also found in RES-sensitive BC cells, and the inhibition rate of ferroptosis inhibitors increased to 22.57% of BCDOs. In addition, the supplementary experiment also indicated that it may be related to apoptosis and autophagy pathways. The above cellular and molecular alterations were not distinct in RES-insensitive BCDOs. Conclusion: RES possesses promising inhibitory effects on either BC cell lines or a large part (10/18) of BCDOs via enhancing oxidative stress and triggering the ferroptosis pathway or more. These findings underscore anti-BC properties of RES and its role as a potential personalized treatment option.