PLA2G2F suppresses ferroptosis through phospholipid remodeling
摘要
Ferroptosis is an iron-dependent form of regulated cell death driven by phospholipid peroxidation, and it has emerged as a potential therapeutic vulnerability of cancer. Here we identify the secretory phospholipase PLA2G2F (phospholipase A2 group IIF) as a ferroptosis suppressor in bladder cancer and elucidate its regulation and mechanism of action. PLA2G2F functions through an intracellular mechanism by localizing to the endoplasmic reticulum to inhibit ferroptosis. Our genetic and pharmacological analyses reveal that peroxisome proliferator-activated receptor γ (PPARG), a nuclear hormone receptor and transcription factor previously implicated in ferroptosis regulation, upregulates PLA2G2F and that PPARG-mediated ferroptosis resistance is largely dependent on PLA2G2F in bladder cancer. Further, lipidomic profiling suggests that PLA2G2F preferentially acts on ether-linked phospholipids containing polyunsaturated fatty acids, thereby reducing the pool of peroxidation-prone polyunsaturated fatty acid-containing phospholipids. Together, our findings establish PLA2G2F as an endoplasmic reticulum-resident ferroptosis suppressor regulated by PPARG and show that inhibiting PPARG signaling or PLA2G2F activity can sensitize bladder cancer cells to ferroptosis induction.