In the previous study, expression of both CXCR4 and its ligand CXCL12 in VHL-null 786-O cells, even in the lack of exogenous CXCL12, may promote ccRCC proliferation and metastatic dissemination by stimulating autocrine receptors. The gene discussed is CXCL12; the disease is nonpapillary renal cell carcinoma.