As consistently shown by qRT-PCR and Western blot analysis, TIMP1 was abundantly expressed in A498 and Caki-1 mesenchymal cells, which exhibit higher N-cadherin and lower E-cadherin expression than HK2 cells, indicating that that TIMP1 level may be related to the mesenchymal phenotype of ccRCC cell line. The gene discussed is CDH1; the disease is nonpapillary renal cell carcinoma.