In the case of cytokines, the secretion of at least five of them (i.e., CCL2 (i.e., C-C Motif Chemokine Ligand 2), CXCL1 (C-X-C Motif Chemokine Ligand 1), IL6, IL8, ICAM1 (Intercellular Adhesion Molecule 1)) is specifically induced in CAFs obtained using metastatic melanoma cells (WM9) and undetected in primary melanoma-derived CAFs (Fig. 7A, C). This evidence concerns the gene XCL1 and metastatic melanoma.