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. The gene discussed is PDE2A; the disease is head and neck squamous cell carcinoma.