Beside the effect on tumour dissemination, CXCR4 as well as other chemokine receptors have also been implicated in various aspects of tumour progression such as cancer cell proliferation and survival as well as in the regulation of the leukocytic and endothelial milieu within the tumour environment (Vlahakis et al, 2002; Koizumi et al, 2007). The gene discussed is CXCR4; the disease is cancer.