Research progress of immune heckpoint LAG-3 in gastric cancer: a narrative review

In recent years, the immunotherapy of gastric cancer has made a breakthrough. With the emergence of immune checkpoint inhibitors, blocking the inhibitory molecules in the body can reactivate the immune system to resist tumors, which dramatically improves the survival rate of gastric cancer patients. Lymphocyte activation gene-3 (LAG-3), also known as CD223, is a kind of immune checkpoint receptor protein, mainly expressed in activated immune cells, and it has the functions of maintaining internal environment stability and immunological regulation and is closely related to the occurrence and development of tumor. Therefore, LAG-3 can be used as a new target for tumor immunotherapy. In this narrative review, the structure, immunological function, and research progress of immune checkpoint LAG-3 in gastric cancer is explored to provide a reference for further research and immunotherapy of gastric cancer.