LAG3 and cancer: Among these receptors, lymphocyte activation gene 3 (LAG-3) has great potentiality in cancer immunotherapy because co-expression of PD-1 and LAG-3 was often found in T-cell-depleted immune microenvironment, and PD-1 inhibitors combined with LAG-3 blockades showed strong synergic antitumor responses in preliminary models (169).