XCL2 and nonpapillary renal cell carcinoma: This signature was established by the overexpression of a group of 11 NK cell-associated genes that are not expressed or are weakly expressed on CD8+ T cells: NCR1, XCL2, IL2RB, KLRF1, KIR2DL4, KLRC3, XCL1, NKG7, CTSW, NCR3, and IL18RAP. We observed that CD85j (Figure 5A), CD45 (Figure 5B), CD48 (Figure 5C) and PD-1 (Figure 5D) were significantly overexpressed in ccRCC.