NK cells exert cytotoxic effects through four main mechanisms: secreting cytokines to directly act on target cells; tumor-specific antibodies binding to CD16 on NK cells to induce ADCC effects [36]; releasing perforin and granzyme B to lyse tumor cells; and activating FASL, TRAIL, and their ligands to mediate death receptor pathways, thereby inducing target cell death. The gene discussed is PRF1; the disease is neoplasm.