In osteosarcoma, Ewing sarcoma, and rhabdomyosarcoma cell lines, increased IL-12 expression levels by lentiviral transduction successfully induced elevated levels of IFN-γ release from NK cells in vitro without systemic toxicity due to IL-12 injection, which provides a new idea for NK cell-based tumor immunotherapy. The gene discussed is IFNG; the disease is neoplasm.