Then we treated BMDMs with IL‐4 and found xCT KO in macrophages markedly suppressed IL‐4‐mediated SOCS3‐STAT6‐PPAR‐γ pathway, as well as the expression of factors including Arg1, CD206 and CD163(Figure 4P,Q), suggesting that xCT KO disrupted macrophage responsiveness to IL4 in tumor microenvironment, but not the production of IL4 cytokine. The gene discussed is ARG1; the disease is neoplasm.