Similarly, overexpression of ITGA2 in esophageal squamous cell carcinoma cell lines promoted EMT and metastasis through FAK/AKT pathway [49] and also showed chemotherapy resistance in gastric cancer, while ITGA2 knockdown restored chemosensitivity by inducing apoptosis in chemoresistant cells [50]. Here, PTK2 is linked to esophageal squamous cell carcinoma.