By blocking LAG-3 through the infusion of anti-mouse LAG-3 antibodies, the investigators observed an inhibition of tumor progression in mice, along with a significant increase in the antitumor response mediated by CD8+ T cells and a consequent reduction in the number of immunosuppressive cells, such as Tregs, and MDSCs, in the HNSCC mouse model. Here, LAG3 is linked to head and neck squamous cell carcinoma.