In order to further screen the key anoikis genes in the process of ccRCC metastasis, we intersected anoikis-related genes, DEGs from TCGA-KIRC, and DEGs from GSE22541 (ccRCC with metastasis) and finally obtained five candidate genes: MMP9, BIRC3, MUC1, HMCN1 and ANGPTL4 (Supplementary Figure 7A). This evidence concerns the gene MMP9 and nonpapillary renal cell carcinoma.