Notably, CAFs suppressed T cell activity in two distinct ways: directly through PD1/PDL1 interaction and secretion of inhibitory molecules (such as TGF-β) and indirectly through inducing immunosuppressive phenotypes in the tumor-associated immune cell, such as macrophage M2 phenotype differentiation and recruitment of MDSCs and Treg cells [76, 77]. Here, TGFB1 is linked to neoplasm.