LRPPRC-Driven Oxidative Phosphorylation Is Associated with Elesclomol-Induced Cuproptosis in Ovarian Cancer

Mitochondrial oxidative phosphorylation serves as a critical driving force in the progression of ovarian cancer. Recent studies have demonstrated that copper induces mitochondrial-dependent programmed cell death by directly binding to the thioacylated components of the tricarboxylic acid (TCA) cycle. The involvement of copper in OXPHOS complex IV, a rate-limiting step in the mitochondrial respiratory chain, suggests that the role of mitochondria in mediating copper-induced cell death can be further elucidated through the study of OXPHOS complex IV. The findings of this study indicate that the cuproptosis process in ovarian cancer, induced by Elesclomol, is associated with mitochondrial complex IV, with LRPPRC identified as a crucial factor. Following Elesclomol treatment of ovarian cancer cells, there was a notable increase in mitochondrial reactive oxygen species (ROS), a significant accumulation of the copper death marker protein DLAT, and a marked decrease in the lipoic acid synthesis-related protein FDX1. Furthermore, the expression levels of copper ion transporters ATP7B and CTR1, which are involved in the assembly and translation of complex IV, as well as the core subunit MTCO1 of complex IV, the copper chaperone protein SCO1, and the interacting protein LRPPRC, were significantly diminished. Inhibition of the IV-stabilizing protein LRPPRC in the ovarian cancer cell lines A2780 and SKOV3 through RNA interference resulted in increased sensitivity to Elesclomol. Concurrently, the expression levels of FDX1, LIAS, LIPT1, SCO1, and MTCO1 decreased significantly. These findings suggest that LRPPRC plays a role in inhibiting the expression of lipoic acid and copper chaperone proteins during Elesclomol-induced copper death in ovarian cancer. This inhibition collectively diminishes the expression and activity changes in complex IV, induces mitochondrial dysfunction, and promotes cuproptosis in ovarian cancer. This study further demonstrates that inhibiting the oxidative phosphorylation complex IV can enhance copper-induced cell death in ovarian cancer.