IL13 and neoplasm: M2 macrophages—“bad macrophages,” induced by Th2 cytokines (e.g., IL-4, IL-10, IL-13), produce anti-inflammatory cytokines (e.g., IL-10, IL-13, TGF-β) promoting tumor growth, ECM remodeling to facilitate tumor invasion, metastasis, angiogenesis, and immune suppression [18,19].