PDCD1 and neoplasm: In addition, in a mouse lung cancer model, XBP1 was found to upregulate the expression of IL10, TGFβ, and Arginase1 associated with M2 macrophages, downregulate the expression of IL-12, TNF-α, and iNOS associated with M1 macrophages, facilitate M2 polarization, decrease M2 macrophages in the tumour region, and enhance T-cell infiltration, thereby improving the efficacy of anti-PD1 therapy [204].