Lung tumor growth or some cytokines, such as IFN-γ, induce Tregs polarization to a TH1-like state, and Tregs then increase the expression of CXCR3, IFN-γ and T-bet and suppress DC1s, thereby restraining CTL activation and inducing CTL dysfunction, which might result in CTLs not infiltrating into the tumor microenvironment. Here, IFNG is linked to neoplasm.