found that the synergistic effects of LAG3 with other immune checkpoints, including PD-L1, TIGIT, CD27/28/40/48/86, cytotoxic T lymphocyte-associated antigen-4 (CTLA-4), ICOS, and IDO1, which may co-regulate the immune microenvironment of breast cancer, are prominent (31). Here, LAG3 is linked to breast cancer.