Multi‐Target Effects of Novel Synthetic Indanedione‐Based Spirotransdicalinol Compound 4l in Autosomal Dominant Polycystic Kidney Disease

Autosomal dominant polycystic kidney disease (ADPKD) is a common genetic disorder characterized by the development of fluid-filled cysts in the kidneys. Tolvaptan is the only FDA-approved drug to treat ADPKD, which has significant side effects, prompting the need for safer novel treatments. Given the pathophysiological similarities between ADPKD and malignant tumors, repurposing anti-cancer compounds signifies a promising strategy. In this study, we explored the therapeutic potential of a novel spirocyclic compound 4l with anti-cancer effects in ADPKD. Our preliminary results demonstrated that 4l reduced cell viability in a dose-dependent manner and inhibited cyst growth in 3D culture. Transcriptomic analysis indicated hypoxia-related pathways, mitophagy, and necroptosis (Ripk1 and Mlkl activation) as key mechanisms, alongside cell cycle arrest via Cdkn1a-Rb1 pathway and inhibition of fibrotic markers (Tgfb2 and Col4a6). To strengthen the translational relevance, we established an ADPKD iPSC-derived renal epithelial model, confirming successful differentiation into proximal tubule/collecting duct-like cells (LTL/DBA staining and upregulation of renal markers AQP1, LRP2, and GATA3). Differentiated ADPKD cells exhibited hyperproliferation, reflecting the cystic epithelium observed in vivo. 4l treatment significantly reduced cell viability without immediate cytotoxicity, suggesting a cytostatic effect. Our findings emphasize 4l as a multi-target agent, proficient in reducing cystogenesis through mitophagy induction, modulation of necroptosis, cell cycle inhibition, and suppression of fibrosis. 4l's efficiency across 2D, 3D, and iPSC-derived models highlights its therapeutic potential. This study also recognizes mitophagy and necroptosis as novel targets in ADPKD and corroborates iPSC-derived renal cells as a powerful platform for drug screening.