Importantly, it was found that the expression levels of immune checkpoint related genes, such as PDCD1, LAG3, TNFSF14 and CTLA4, were significantly elevated in cluster 3, which indicated that ccRCC samples of cluster 3 are beneficial to reshape the immune-rejection microenvironment (Figure 5C). The gene discussed is PDCD1; the disease is nonpapillary renal cell carcinoma.