TIMER2.0 analysis of 471 melanoma samples (368 metastatic, 103 primary) by single-cell RNA-seq revealed that PDPN expression was inversely correlated with infiltration by antitumor immune populations (CD4+ T cells, CD8+ T cells, NK cells, and M1 macrophages), and positively correlated with immunosuppressive populations (M2 macrophages, regulatory T cells), most notably with M2 macrophages (Supplementary Table 1). The gene discussed is CD4; the disease is melanoma.