IL1B and neoplasm: While IMCs normally differentiate into mature neutrophils, macrophages, and DCs upon entering peripheral blood and tissues, tumor-derived soluble factors and pro-inflammatory cytokines in the TME such as IFN-γ, IL-1β, IL-4, and IL-10 instead drive the differentiation of IMCs into MDSCs and later into immunosuppressive macrophages and DCs (Figure 1B) (Bunt et al., 2006; Gallina et al., 2006; Gabrilovich et al., 2012).