Figure 1.

Interaction and functions of immune cells in HCC tumor microenvironment. MDSC can secrete TGF-β, IL-10 and recruit Treg by expressing CD40. TAM can produce chemokines CCL22 and CCL17, and recruit Treg to transfer to cancer sites. IL-10 secreted by Treg promotes M2 polarization of TAM. DC promotes Treg by reducing IL-12 secretion. The number of NK cells in tumor tissues of HCC patients decreased, and the levels of IFN-γ and TNF-α secreted by NK cells decreased, but NK cells increased the expression of TIM-3. After blocking TIM-3, the function of depleted NK cells recovered rapidly. Created with BioRender.com.