Fig. 2

Tregs interact with immune cells and the therapies in liver cancer. Tregs suppress anti-liver cancer immunity via interacting with several immune cells. Firstly, Tregs inhibit APCs’ function in liver cancer, currently known mechanisms like CTLA-4 ligand expression to down-regulate DCs’ CD80/86 and IL-10 secretion to inhibit DCs maturation, TLR-4 signal mediated immune suppression with macrophage participant. And the APCs suppression may be rescued by drugs like cabozantinib and CTLA4 blockade. Secondly, Tregs suppress FOXP3⁻ T cells in liver cancer such as effector T cell (consuming IL-2 with highly expressed CD25; PD-1 correlated dysregulation) and γδ T cell (depending on TGF β and IL-10), which can be partially blocked by GITRL therapy. And regulatory T cell itself can be depressed by CD4⁺CD25⁺ Tregs’ proportion decreaser solanine and FOXP3 expression inhibitor astragalus polysaccharides for liver cancer therapy. CTLA-4, cytotoxic T lymphocyte associated antigen-4; IL-2, interleukin-2; IL-10, interleukin-10; TLR-4, Toll like receptor-4; PD-1, programmed cell death-1; PD-L1, programmed cell death-ligand 1; TGF β, transforming growth factor β; GITRL, glucocorticoid induced tumor necrosis factor receptor ligand; CD25, cluster of differentiation 25