FAS and neoplasm: Circulating Treg are highly susceptible to CD95‐FASL‐dependent apoptosis but not to TCR‐mediated cell death in contrast to effector T cells.11 Treg in the tumor undergo CD95‐dependent cell death as a consequence of FASL expression by tumor cells.37 We have reported previously that BECs express FASL in inflammatory liver diseases,14 but we have not explored the role of Fas in the differential fate of bile duct‐associated Treg and CD8 cells.