Adoptive transfer of T-cells with a TCR and inducible IL-12 to melanoma-bearing mice resulted in severe toxicity with high levels of IFNγ and TNFα in blood, whereas T-cell activation upon interaction with melanoma cells promoted IL-18-mediated cytotoxic response against tumor without side effects, enhancing the presence of T-cells within tumors, and reducing tumor burden. The gene discussed is IFNG; the disease is melanoma.