First, we compared the expression of ACE2 mRNA in ccRCC and adjacent normal tissues based on four GEO datasets (GSE40435, GSE53757, GSE66272 and GSE126964), and found that ACE2 mRNA expression was down-regulated in ccRCC tissues compared with adjacent normal tissues (Figure 1A). The gene discussed is ACE2; the disease is nonpapillary renal cell carcinoma.