Enhancing of Nanocatalyst-Driven Chemodynaminc Therapy for Endometrial Cancer Cells Through Inhibition of PINK1/Parkin-Mediated Mitophagy

Purpose: Iron-based nanomaterials have recently been developed as excellent and potent Fenton reagents to reactive oxygen species (ROS) during chemodynamic therapy (CDT). The performance of the materials, however, can be impaired by the intrinsic antioxidant defense mechanism in organisms, such as autophagy. Methods: The nanoscale metal-organic frameworks (nMOFs), nMIL-100 (Fe), were exploited and characterized. Also, the Fenton-like catalytic characteristics, anti-endometrial cancer (EC) effects and potential mechanisms of nMIL-100 (Fe) nanoparticles were investigated in vitro. Results: The synthesized nMIL-100 (Fe) nanocatalyst catalyzed hydroxyl radicals (·OH) production in the presence of hydrogen peroxide (H 2 O 2 ) and simultaneously depleted intracellular glutathione (GSH). Combining with H 2 O 2 , nMIL-100 (Fe) nanoparticles exhibited enhanced cytotoxicity for EC cells, especially for progesterone treatment-insensitive KLE cells, probably due to relatively lower expression of the catalase gene. The accumulated ·OH initiated PTEN induced putative kinase 1 (PINK1)/E3 ubiquitin-protein ligase Parkin-mediated cytoprotective mitophagy in turn to partially rescue ·OH-induced cell apoptosis. Furthermore, both pretreatments of EC cells with siRNA-mediated Parkin knockdown and Mdivi-1 (a mitophagy inhibitor) addition were sufficient to ensure nMIL-100 (Fe) synergizing with H 2 O 2 -induced oxidative damages. Conclusion: These results suggest that the degree of mitophagy should be taken into consideration to optimize therapeutic efficiency when developing ROS based-CDT for EC cancer therapies. Therefore, a nMIL-100 (Fe)-guided, elevated ROS and overwhelmed mitophagy-mediated therapeutic strategy may have greater promise for EC therapy compared with current treatment modalities. Keywords: mitophagy, chemodynamic therapy, metal-organic frameworks, nanocatalyst, endometrial cancer