PHB2 and esophageal squamous cell carcinoma: It has been reported that commonly up-regulated PHB2 has been found in certain tumors, such as esophageal squamous cell carcinoma (ESCC), non-small cell lung cancer (NSCLC), and hepatocellular carcinoma, and PHB2 is considered as a prognostic marker for ESCC and NSCLC [25–27].