DDR2 and melanoma: Using this analysis, we could also label the links in the cell-cell interaction network map in the melanoma tissues with the specific by ligand-receptor pairs (Fig. 8b): melanoma tumor cells talked to CAF cells mainly through the three ligand-receptor pairs CTGF-LRP1, C1QB-LRP1 and COL1A2-ITGA11; conversely, CAF cells “talked back” through CYR61-CAV1, CTGF-LRP1 and COL3A1-DDR2.