PDCD1 and esophageal squamous cell carcinoma: In addition, m6A-related signature has been identified as biomarker for tumor immune phenotypes and anti-PD-1 immunotherapy treatment response in lung adenocarcinoma (LADC) (72, 73), stomach adenocarcinomas (STADs) (74), Esophageal squamous cell carcinoma (ESCC) (75, 76), Renal Papillary Cell Carcinoma (RPCC), Hepatocellular Carcinoma (HCC) (77, 78).