As the most important marker of lipid browning, UCP1 is also a key molecule for initiating lipid browning.28 As shown in Figure4A–E, UCP1 mRNA and protein levels were significantly lower in ccRCC tissues than in normal tissues, and there was also a lower UCP1 expression in ccRCC cell lines (786‐0, A498, ACHN, CAKI, OSRC) compared with normal cell line (293). This evidence concerns the gene UCP1 and nonpapillary renal cell carcinoma.