Intriguingly, ADAR1 exhibited remarkably high expression in most cancer types, comprising bladder cancer (BLCA), breast cancer (BRCA), cholangiocarcinoma (CHOL), esophageal carcinoma (ESCA), head and neck squamous cell carcinoma (HNSC), liver hepatocellular carcinoma (LIHC), lung adenocarcinoma (LUAD), lung squamous cell carcinoma (LUSC), pheochromocytoma and paraganglioma (PCPG), and stomach adenocarcinoma (STAD) (Fig. 1A). This evidence concerns the gene ADAR and pheochromocytoma-paraganglioma.