PRF1 and neoplasm: Subsets such as Vγ9Vδ2 and Vδ1+ T cells mediate anti-tumor responses via perforin/granzyme-dependent cytolysis and through engagement of death receptors (e.g., FasL, TRAIL), along with secretion of IFN-γ and TNF to promote effector cell recruitment and antigen presentation [160–162].