JS-K induces autophagy-dependent ferroptosis in bladder cancer: a multimodal mechanistic and translational study.

Abstract

Background: Bladder cancer is the most common urological malignancy. Bladder cancer has limited therapeutic options, especially in advanced stages. Ferroptosis, an iron-dependent form of regulated cell death, has emerged as a promising target for cancer therapy. However, the role of autophagy in modulating ferroptosis remains incompletely understood.

Methods: We investigated the anti-tumor effects of JS-K, a nitric oxide-releasing prodrug, in bladder cancer through integrated cell, animal, and patient data studies. In vitro experiments with T24 and UM-UC-3 cells were used to explore how JS-K influences cancer cell survival and the interplay between autophagy and ferroptosis. In vivo, a BALB/c nude mouse tumor model provided a system to examine tumor response and tissue-level changes. To extend these findings to the clinical setting, we analyzed LC3B expression and its associations with ferroptosis-related genes, patient prognosis, and the tumor immune microenvironment.

Results: JS-K induced mitochondrial damage, lipid peroxidation, reactive oxygen species accumulation, and intracellular iron overload in bladder cancer cells in a concentration-dependent manner. These changes were accompanied by downregulation of GPX4 and SLC7A11 and upregulation of FTH1 and TFR1, indicative of ferroptosis. Inhibition or knockdown of the autophagy marker LC3B reversed these effects, establishing the role of autophagy in mediating ferroptosis. In xenograft models, JS-K suppressed tumor growth, an effect abrogated by LC3B silencing. Integrated transcriptomic and single-cell analyses revealed a strong correlation between LC3B and ferroptosis-related genes, with CISD1 identified as a key prognostic marker.

Conclusions: JS-K induces autophagy-dependent ferroptosis in bladder cancer cells and significantly suppresses tumor progression. Targeting the autophagy-ferroptosis axis offers a novel therapeutic strategy for bladder cancer treatment.