TAMs that originate from circulating monocytes are recruited to the hypoxic tumor area by tumor-derived factors, such as colony-stimulating factor-1 (CSF-1), VEGF-A, and chemokine (C–C motif) ligand 2 (CCL2) (Lin et al. 2019; Pathria et al. 2019). Here, CCL2 is linked to neoplasm.