The expression of ESM1 is mostly detected in endothelium cells (18) and is prominently upregulated in multiple neoplasms including hepatocellular carcinoma (19), bladder cancer (20), head and neck squamous cell carcinoma (HNSCC) (21), colorectal cancer (22), nonsmall cell lung cancer (NSCLC) (23), etc. Additionally, serum endocan also could be detected in a crowd of patients with cancers (24–26). Here, ESM1 is linked to head and neck squamous cell carcinoma.