Moreover, in vivo treatment of TCL1-tg mice allowed for further insight into the clinical effects of PF-04691502: inhibition of CXCL12-mediated migration toward spleen and lymph nodes (LNs) induced redistribution of the tumor cells from lymphoid organs to the blood, followed by a marked reduction of tumor burden due to the cytotoxic activity of the drug. The gene discussed is CXCL12; the disease is neoplasm.