Figure 1.

A simplified overview of interactions between tumor cells and TME-associated immune cells. CD4⁺(FoxP3⁻) and CD8⁺ T cells are designed for tumor cell elimination, though their function can be altered by recruitment of pro-tumorigenic (M2) TAMs and FoxP3⁺ Treg, who interact in a positive feedback-loop. TNFα = Tumor necrosis factor alfa. TGFβ = Tumor growth factor Beta; IL = Interleukin; IFNγ = Interferon gamma; Arg1 = Arginase 1; iNOS = inducible nitric oxide synthase; ROS = reactive oxygen species, PD-1 = programmed death 1, PD-L1 = programmed death ligand 1, CTLA-4 = cytoxic T-lymphocyte associated protein 4, MHC = major histocompatibility complex, TCR = T cell receptor.