FAS and Autoimmunity: Fas (TNFRSF6/CD95), a member of the tumor necrosis factor receptor superfamily, can either induce apoptosis, which is essential for shutting down chronic immune responses1–3 and preventing autoimmunity and cancer4, or mediate cell survival, proliferation, and motility, which can promote autoimmunity, cancer growth, and metastasis5–10.