Fig. 3From: The tumor ecosystem in head and neck squamous cell carcinoma and advances in ecotherapyOverview of protumor effects of TAMs in head and neck squamous cell carcinoma. TAMs promote tumor progression by participating in tumor invasion, metastasis, and angiogenesis as well as immunosuppression. Abbreviations: CCL2, C–C chemokine ligand 2; CCR2, CC chemokine receptor 2; ECM, extracellular matrix; HLA-G, human leucocyte antigen-G; IL-6, interleukin-6; MMP9, matrix metalloproteinase 9; PD-L1, programmed death-ligand 1; TAM, tumor-associated macrophage; TGF-β, transforming growth factor-beta; VEGF, vascular endothelial growth factorBack to article page