PDE2A and nonpapillary renal cell carcinoma: Our findings revealed significant downregulation of PDE2A protein levels in hepatocellular carcinoma (HCC), BRCA, LUAD, LUSC, head and neck squamous cell carcinoma (HNSC), GBM, clear cell renal cell carcinoma (CCRCC) and UCEC, as shown in Figure 2C.