To determine whether the phenotypic changes in KDF1 overexpressing ccRCC cells is caused by the increased KDF1 in the cells, we knocked down the expression of KDF1 in the KDF1 overexpressing cells by transducing them with a shRNA overexpression recombinant lentivirus, which was designed to express a shRNA targeting KDF1. The gene discussed is KDF1; the disease is nonpapillary renal cell carcinoma.