CCL2 and neoplasm: CCR2+ bone marrow-derived monocytes are readily recruited to primary and secondary tumours in multiple tumour types by the chemokine CCL2.79–81 Consequently, the CCL2–CCR2 axis represents one point at which the accumulation of metastasis-associated macrophages (MAM) could be prevented.82,83 CCR2 small molecule antagonists are effective in transplantable models of pancreatic cancer and hepatocellular carcinoma,80,84 suggesting that secondary tumours may also be susceptible to these drugs.