The treatment with PD-1 antibody increases the secretion of IFN-γ in activated infiltrating CD8+T cells, which further suppresses the expression of subunits of glutamate-cystine antiporter system Xc- and leads to restrained tumor cell cystine uptake, potentiated lipid peroxidation, and ultimately ferroptosis (115, 116). The gene discussed is PDCD1; the disease is neoplasm.