In response to tumor cells or Th2-derived stimuli (IL-4, IL-10, IL-13, TGF-β) [24] macrophages differentiate to M2 TAMs characterized by the production of IL-4, IL-5, IL-10, C-C Motif Chemokine Ligand 2 (CCL2), CCL17, C-C Motif Chemokine Receptor 2 (CCR2), C-X-C Motif Chemokine Receptor 1 (CXCR1), CXCR2, and high levels of programming death-ligand 1 (PD-L1) to promote angiogenesis and immune system suppression [24]. Here, CXCR1 is linked to neoplasm.