AZIN2 and nonpapillary renal cell carcinoma: In the TCGA-ccRCC cohort, ARG1, ATP13A2, ATP13A3, AZIN2, OAZ1, OAZ2, OAZ3, PAOX, SMOX, and SRM were highly expressed in cancer tissues, whereas AZIN1, ODC1, SLC18B1, and SMS had low expression levels in cancer tissues, compared with corresponding normal tissues (Figure 1A).