Co-expression analysis among immune checkpoint molecules and NOP2 presented that NOP2 was markedly related to PDCD1 (PD1), CTLA4, CD274 (PDL1), LAG3, etc., in ccRCC from TCGA dataset (all P < 0.05, Figure 9(c)). Here, CTLA4 is linked to nonpapillary renal cell carcinoma.