TGFB1 and hepatocellular carcinoma: However, a number of molecules and signaling pathways have been implicated in Treg-induced immune tolerance: (a) the emergence of other immune checkpoints from Tregs, such as TIM-3, TIGIT, LAG3, and VISTA, blocks effector T cell activation, and their high expression is often associated with poor prognosis in HCC patients after anti-PD-1/PD-L1 treatment (63, 64); (b) TGF-B secreted by Tregs induces EMT and promotes the invasion and migration of HEPA1-6 cells.