Targeting tumor-associated macrophages in head and neck squamous cell carcinoma.

In head and neck squamous cell carcinoma (HNSCC), tumor-associated macrophages (TAMs) are associated with a poorer prognosis. TAMs, derived from inflammatory monocyte, play a critical role in regulating tumor progression. Generally, TAMs promote tumor progression and suppress immune response via both innate and adaptive immune mechanisms. However, as the double-blade sword, TAMs retain the potential pro-inflammatory ability to inhibit tumor progression. By depleting the immunosuppressive function or evoking anti-tumor ability, therapeutic strategies targeting TAMs show promising preclinical and clinical effects. Now, macrophage-centered therapeutic approaches are entering the clinical arena. In this review, we discuss the immunosuppressive role of TAMs in the tumor microenvironment and the therapeutic approaches targeting macrophages which offer promise in improving HNSCC outcome.