TUBB6 and nonpapillary renal cell carcinoma: We found that the expression of IRF6, TEK, ABCB1, and COL4A5 was downregulated in ccRCC tissues compared to that in adjacent normal tissues, and the expression of PLCB2, TGFA, PLOD2, and TUBB6 was upregulated in ccRCC tissues compared to that in adjacent normal tissues (Supplementary Figure 6).