Clinical studies have found that the expression level of OX40 in the gastric mucosal immune microenvironment of gastric cancer patients is increased, and the OX40 expression level of stage I and II gastric cancer patients is higher than that of stage III and IV gastric cancer patients [48], suggesting that the immune system of patients with advanced gastric cancer is suppressed and that OX40 may play an important role in the immune microenvironment of gastric cancer. Here, TNFRSF4 is linked to gastric cancer.