The invasiveness and metastatic function of LY6K in cancer as a diagnostic biomarker and therapeutic target has been elucidated in various cancers such as head and neck squamous cell carcinoma, breast cancer, lung and esophageal carcinomas, bladder cancer, and esophageal squamous cell carcinoma [13–18]. This evidence concerns the gene LY6K and esophageal squamous cell carcinoma.