Effect of RSL3 and IFN-γ on gene expression in 526MEL cells

Tumor masses often exhibit heterogeneity, including escape variant clones that lack antigen-presenting machinery and/or tumor antigens, which poses a major challenge to immunotherapy. Ferroptosis, a form of regulated cell death driven by iron-dependent lipid peroxidation, has been shown to effectively induce cell death in various tumor cells. Recent studies have reported that IFN-γ suppresses the expression of System Xc-, thereby enhancing the induction of ferroptosis. Based on this, we hypothesized that combining immunotherapy with ferroptosis inducers could enhance antitumor effects against both antigen-positive and antigen-negative tumor cells. Consistent with this hypothesis, we comprehensively analyzed mRNA expression changes in 526MEL cells treated with the combination of RSL3 and IFN-γ using RNA sequencing. Our data suggest that multiple ferroptosis-related pathways, including the CoQ-dependent membrane repair pathway (FSP1–CoQ axis), the DHODH–CoQ mitochondrial redox pathway (DHODH–CoQ axis), the CYB5R–cytochrome b5 lipid redox pathway (CYB5R axis), and the thioredoxin–peroxiredoxin repair pathway (PRDX/TXN axis), may contribute to the synergistic effects of combined RSL3 and IFN-γ treatment in human melanoma cell lines.