MLN4924 Enhances RSL3-Induced Ferroptosis Sensitivity in Glioblastoma via Inhibiting the STAT3/GPX4 Axis

Glioblastoma (GBM) is one of the most aggressive and treatment-resistant tumors of the central nervous system, demanding innovative therapeutic strategies. Ferroptosis, an iron-driven lipid peroxidation-dependent cell death, has emerged as a potential means to overcome resistance, with glutathione peroxidase 4 (GPX4) as its key suppressor. MLN4924 (pevonedistat), a first-in-class inhibitor of neddylation currently in clinical trials, has shown strong antitumor activity across multiple malignancies. However, its role in ferroptosis regulation and the underlying molecular mechanisms remain poorly defined. Here, we show that MLN4924 induces ferroptosis, with GPX4 emerging as a central regulatory node. GPX4 expression is elevated in gliomas compared to normal brains, and its higher levels correlate with increased grades and worse patient prognosis. MLN4924 downregulates GPX4 mRNA by suppressing STAT3 signaling, whereas RSL3 directly inhibits GPX4 enzymatic activity. The combination of MLN4924 and RSL3 synergistically potentiates ferroptosis and, in vivo, suppresses subcutaneous tumor growth with a considerable biosafety. Collectively, these findings identify GPX4 as the principal mediator of MLN4924-induced ferroptosis and establish that dual targeting of GPX4 transcription and activity represents a promising therapeutic strategy for GBM.