Fig. 4
From: Novel targeted therapies and immunotherapy for advanced thyroid cancers

Immune checkpoints and their proposed mechanism of action in T cells: Several immune checkpoints are overexpressed on T cell surface in thyroid tumor microenvironment and their corresponding ligands on tumor cells or immature dendritic cells. Interaction of receptors and ligands lead to inhibition of the AKT pathway inside T cells and subsequently inhibition of T cell proliferation and division