METTL3 and nonpapillary renal cell carcinoma: We analyzed the mRNA expression levels of 13 m6A-related genes (METTL3, METTL14, WTAP, RBM15, ZC3H13, KIAA1429, FTO, ALKBH5, YTHDC1, YTHDC2, YTHDF1, YTHDF2, HNRNPC) in TCGA database to identify the different expressed genes between ccRCC tissues and normal tissues.