PRF1 and neoplasm: Studies have also revealed that γδ T cells can exert anticancer activity through various mechanisms, such as eliminating tumor cells via the perforin-granzyme pathway (37), binding to TNF-related apoptosis-inducing ligand (TRAIL) and Fas ligand (FasL) (38), via antibody-dependent cellular cytotoxicity (ADCC) (39), or by secreting interferon (IFN)-γ and tumor necrosis factor (TNF)-α (40, 41).