MUC13 and nonpapillary renal cell carcinoma: Expression levels of 9 MUCINs were significantly altered in ccRCC patients (p < 0.05), including six membrane‐bound MUCINs (MUC1, MUC3A, MUC12, MUC13, MUC15, and MUC20), one secreted MUCIN (MUC6), and two atypical MUCINs (EMCN and MCAM) (Figure 2).