CXCR7 is up-regulated in all pathological conditions in which CXCL12 activity is enhanced, including neoplastic diseases, and contributes to tumor growth, adhesion, survival, angiogenesis, and invasion of breast, lung and prostate carcinomas (Miao et al., 2007; Wang et al., 2008) and promotes tumor development in mice (Burns et al., 2006). This evidence concerns the gene CXCL12 and neoplasm.