The inhibitory role of PDGFR-alpha in melanoma was supported by data collected in several hundred melanoma patients' biopsies, showing a significant reduction of PDGFR-alpha expression in melanoma biopsies as compared to normal skin, as well as in metastatic melanoma biopsies as compared to primary melanoma biopsies (Figure 1D, 1E and datasets GDS1375, GDS1989, GDS2200, GDS1965 available at GEO database site http://www.ncbi.nlm.nih.gov/sites/entrez) [31]. This evidence concerns the gene PDGFRA and metastatic melanoma.