By using an NK‐specific Tipe2 knockout mice, in which Tipe2 gene expression was deficient in NK cells with no reduction in the NK cell population size, we previously showed that Tipe2−/− mouse NK cells produce higher levels of IFN‐γ than control mouse NK cells in the tumor.[19] In this study, we further found that tumor‐infiltrating Tipe2−/− mouse NK cells increased the expression of T‐bet and Eomes. The gene discussed is TIPE2; the disease is neoplasm.