CXCR4 and melanoma: We have shown that melanoma cells recruit Au-NPs-loaded ECFCs prepared from cord blood (CB) by the CXCR4 (expressed by ECFCs)-SDF-1 (produced by melanoma cells and associated MSCs) axis in 18 h, and that an anti-SDF-1 neutralizing antibody precludes ECFCs recruitment both in vitro and in vivo [140].