TGFB1 and nonpapillary renal cell carcinoma: Many studies has reported the involvement of signaling pathways such as Notch [51, 52] and TGF-β [53, 54] in the biological and pathological processes of ccRCC, but there are few reports on the involvement of signaling pathways such as Notch and TGF-β regulated by miRNAs in ccRCC development.