CD4 and hepatocellular carcinoma: These HCC-Treg cells may suppress effector cells' proliferation, activation, cytokine secretion, degranulation, and cytotoxic compounds production [84, 85]. In vitro experiments also revealed that isolated HCC-infiltrating CD4+CD25+FOXP3+ regulatory T-cells can directly delete the cytotoxic function and the IFNγ secretion of some effector TIL in a TGFβ- and IL10-dependent manner [62, 86].