Tumor-associated macrophages (TAMs) derived from blood monocytes, myeloid-derived suppressor cells, and tissue resident macrophages are induced and differentiated in tumor tissues by cytokines such as C-C motif chemokine ligand 2 (CCL2), CCL5, and colony-stimulating factor 1 (CSF-1) [7]. Here, CCL2 is linked to neoplasm.