Fig. (1) A schematic illustration of the cellular components and factors responsible for the immune-suppressive mechanisms in the tumor micro environment. Cellular components including Oral Square Cell Carcinoma (OSCC), Myeloid Derived Suppressor Cell (MDSC), Cancer Associated Fibroblast (CAF), Tumor Associated Macrophage (TAM), regulatory T cells (Tregs) and effector T cells, interact mutually using soluble factors, including Interleukins (ILs), C-C Chemokine Ligands (CCLs), Tumor Necrosis Factor (TNF)-α, Tumor Growth Factor (TGF)-β, High Mobility Group Box (HMGB) 1, Granulocyte Macrophage-Colony Stimulating Factor (GM-CSF), Vascular Endothelial Growth Factor (VEGF), Arginase (Arg) 1, Prostaglandin (PG) E2, Nitric Oxide (NO) and lactate. CAFs and Tregs can also interact directly with effector T cells via receptor-ligand interactions, including Programmed cell Death (PD)-1, Cytotoxic T-Lymphocyte-Associated Protein (CTLA)-4, Inducible Co-Stimulator Ligand (ICOSL), V Domain-Containing Ig Suppressor of T-Cell Activation (VISTA) and C-C Chemokine Receptor (CCR) 6.