Our data clearly show anti-tumorigenic properties for the CXCR7 receptor in NB, as CXCR7 was able to affect in vitro migration-promoting effect mediated by the CXCR4/CXCL12 axis, and to delay orthotopic tumor take of CXCR4-positive NB cells. This evidence concerns the gene ACKR3 and neoplasm.