We also tested the expression of MT-RNR1 in ccRCC cell lines, and the results showed that compared with HK2 cells, MT-RNR1 expression was significantly increased in OSRC2 and Caki-1 cells with higher DNA methylation level of ZNF582-AS1 promoter (Fig. 6f). Here, PTGDR is linked to nonpapillary renal cell carcinoma.