All these networks were associated to intracellular signaling pathways known to be active in MDSCs (SRC, Grb2, Ras, Stat3, NF-κB and MAPKs), some of them melanoma MDSC-specific targets such as STAT3 [22] (Fig. 5C and Supplementary Fig. S3). This evidence concerns the gene GRB2 and melanoma.