TGF-β-induced EMT has been implicated in tumor progression and metastasis in many types of carcinomas, including ccRCC.23, 24, 25, 26 However, our understanding of the mechanism underlying the regulation of TGF-β/Smad3 signaling during cancer metastasis remains limited.27 Here, TGFB1 is linked to nonpapillary renal cell carcinoma.