CTLA4 and neoplasm: In reaction to immune checkpoint inhibitors, such as PD-L1 and CTLA-4, CD8+ T cells impede tumor cell cystine uptake and bolster the lipid peroxidation process by downregulating SLC3A2 and SLC711 via the release of IFN-γ, while augmenting T cell-mediated anti-tumor immunity and inducing ferroptosis in tumor cells 223, 224.