Then, we analyzed the differential expression of COMMD2 between the tumors with paired or non‐paired normal samples depending on the TCGA (Figure 1A) and SangerBox databases (Figure 1B), and it was shown that COMMD2 expression was markedly upregulated in BLCA, cholangiocarcinoma (CHOL), colon adenocarcinoma (COAD), esophageal carcinoma (ESCA), HNSC, LIHC, lung squamous cell carcinoma (LUSC), GBM, and stomach cancer (STAD), whereas it was downregulated in kidney renal clear cell carcinoma (KICH), lung adenocarcinoma (LUAD), and thyroid carcinoma (THCA). The gene discussed is COMMD2; the disease is gastric adenocarcinoma.