Previous studies also showed that IL‐18 possesses an antitumor activity in various human cancers 8, 9, 10, 11; for example, treatment of human cancer patients with intravenous injection of recombinant human IL‐18 (rhIL‐18) showed antitumor effects 10 and the combination with other cytokines could also achieve tumor cell killing and tumor inhibitory effects 8, 12. This evidence concerns the gene IL18 and neoplasm.