TREM2 and melanoma: CXCL9, CXCL10, PD-L1, CD86, IL-10, TREM2, GPNMB, IL-4l1 and FOLR2 markers showed widespread expression by most melanoma TAMs, with no definition of a particular macrophage subset, and regardless of whether the tumor was metastasizing or not (Figures 3B, D; Supplementary Figure S1D).