For example, the activation of immune cells, such as CD8+ T cells, through the secretion of INF-γ downregulates the expression of components of system XC−, such as SLC3A2 and SLC7A11, to inhibit the uptake of cystine by tumor cells, thereby promoting ferroptosis induced by the depletion of glutathione (67). This evidence concerns the gene CD8A and neoplasm.