In 2 separate data sets on breast cancer and renal carcinoma, respectively, the GSH metabolism–related gene set, including gclc, gls, gpx4, gss, slc25a39, and e2f1, was enriched along with mki67, top2a, and zwint genes in one particular cluster of intratumoral CD8+ T cells (Figure 7A), presumably linking with a superior proliferative potential. This evidence concerns the gene SLC25A39 and breast cancer.