The in-house anti-PD1 treatment melanoma patients cohort, two public melanoma patients cohorts with immune checkpoint therapy (the Riaz N cohort [21]/GSE91061: Anti-PD1-treated advanced melanoma (Nivolumab)), and the Van Allen, E. M cohort [22]: Anti–CTLA4-treated metastatic melanoma) and other cohorts with immune checkpoint therapy (the Balar AV cohort [23]/IMvigor210: Anti-PD-L1-treated locally advanced and metastatic urothelial carcinoma and the Braun DA cohort [25]: anti-PD-1-treated advanced clear cell renal cell carcinoma) were taken for analysis. The gene discussed is PDCD1; the disease is metastatic melanoma.