Like TGF-β, the Fas ligand-mediated T cell death signal that is highly expressed in the TME can also be converted into pro-survival signal via CSR, by fusing the Fas extracellular domain with the 4-1BB intracellular domain (231), resulting in engineered T cells with increased pro-survival signaling, proliferation, antitumor function, and enhanced in vivo efficacy against leukemia and pancreatic cancer mouse models. This evidence concerns the gene FAS and leukemia.