Dual novel compounds destroy mitochondrial morphology and function to treat glioblastoma by promoting the p62-mediated protein degradation of mitochondrial respiratory chain complex.

Therapeutic efficacy of temozolomide (TMZ) remains limited, and GBM patients generally experience poor outcomes due to the presence of multiple mechanisms of TMZ resistance. Previously, we developed two novel compounds: EPIC-1027, which targets HOTAIR/PRC2 complex, and EPIC-1042, which disrupts interaction between PTRF and CAV1. In this study, we aim to establish a novel combinatorial strategy for GBM by targeting mitochondrial function. Proteomics was employed to evaluate global protein alterations induced by EPIC-1027 and EPIC-1042. Super-resolution microscopy and transmission electron microscopy were used to characterize changes in mitochondrial morphology. Metabolic flux analysis was performed to assess alterations in cellular energy metabolism following combined treatment. An intracranial GBM model was established to validate the anti-GBM efficacy of EPIC-1027 and EPIC-1042 in vivo. Combined treatment with EPIC-1027 and EPIC-1042 reduced the abundance of respiratory chain complex proteins by promoting p62-dependent protein degradation, resulting in severe mitochondrial damage. Both glycolytic activity and oxidative phosphorylation were markedly suppressed following EPIC-1027 and EPIC-1042 treatment. In vitro, EPIC-1027 and EPIC-1042 exerted a synergistic inhibitory effect on GBM cell proliferation and significantly induced apoptosis in an MGMT-independent manner. In vivo, combined treatment with EPIC-1027 and EPIC-1042 significantly attenuated tumor growth and prolonged survival in mice bearing orthotopic GBM. Our study demonstrates that combined treatment with EPIC-1027 and EPIC-1042 induces mitochondrial structural abnormalities and functional impairment, leading to suppressed proliferation and enhanced apoptosis. These findings identified a novel combinatorial therapeutic strategy targeting mitochondria for the treatment of glioblastoma.