Other immune approaches, in order to suppress MDSC functions and/or recruitment, are also being tested in HNSCC treatment, such as the depletion of MDSC along with anti-CTLA-4 monoclonal antibody (in order to enhance anti-CTLA-4 antitumor effects) [49], the use of STAT3 (AZD9150), and the recruitment of inhibitors (e.g. MJ18, a B7-H3 antagonist; AZD5069, a CXCR2 antagonist) [50, 51]. Here, CTLA4 is linked to head and neck squamous cell carcinoma.