SFTPB and nonpapillary renal cell carcinoma: In this study, we performed bioinformatics analysis and identified 11 hub genes [fibulin 1(FBLN1), thrombospondin 2 (THBS2), secretoglobin family 1A member 1 (SCGB1A1), NK2 homeobox 1 (NKX2-1), collagen type XI alpha 1 chain (COL11A1), decorin (DCN), lumican (LUM), collagen type I alpha 1 chain (COL1A1), collagen type VI alpha 3 chain (COL6A3), surfactant protein C (SFTPC), and surfactant protein B (SFTPB)] and three key miRNAs (miR-328, miR-502, and miR-504), and established a novel mRNA-miRNA network in metastatic ccRCC.