FIGURE 2.

Proposed models for the molecular mechanisms of immunomodulatory effects by natural productions. Inhibitory effects of natural products on tumors through enhancing the cytotoxic function of effect T cells and NKs, attenuating CD4⁺CD25⁺Foxp3⁺ regulatory T cells (Tregs), reducing myeloid‐derived suppressor cells, decreasing TGF‐β, IL‐10, IL‐5, indoleamine 2,3‐dioxygenase, ARG1 levels, inducing IL‐12, IFN‐γ, and TNF‐α/β production, and preventing cell‐cell interaction of Tregs via the inhibition of CTLA‐4 and PD‐L1