The increased expression of CXCR7 in lymphoid leukemia cells detected in this study is a phenomenon observed in a variety of solid tumors such as brain, prostate, lung, breast, prostatic, renal and glioma cells in which the increased expression of CXCR7 has been positively correlated with aggressive tumor behavior [15], [33]. The gene discussed is ACKR3; the disease is lymphoid leukemia.