Finally, due to the promise associated with immune checkpoint inhibitor therapy for cancer treatment, we further determined the association between ATG5 and PD-1 and CTLA-4 expression (Figure S4C), and found that there was a negative correlation between ATG5 and PD-1 (r = −0.069, P < 0.05) as well as between ATG5 and CTLA-4 (r = −0.04, P = 0.11) in BRCA and SKCM tumors. Here, CTLA4 is linked to cancer.