PLOD2, highly expressed in esophageal squamous cell carcinoma, promotes the invasion and metastasis of esophageal squamous cell carcinoma through the epithelial to mesenchymal transition via the FAK/AKT signal pathway (Di et al., 2019; Dongre and Weinberg, 2019). The gene discussed is PTK2; the disease is esophageal squamous cell carcinoma.