To determine the biological role of FUBP1 in the proliferation of human ccRCC cells, we used chemically synthesized siRNAs, which were designed to target distinct sites of FUBP1 mRNA for knocking down endogenous FUBP1 in ccRCC cell lines of 786-O and caki-1. The gene discussed is FUBP1; the disease is nonpapillary renal cell carcinoma.