Various animal studies showed that HIF-1α regulates many chemokines that may induce recruitment of BMDCs into tumours, including chemokine ligand 2 (CCL2 or MCP1)29, colony-stimulating factor-1 (CSF-1)30, 31, 32, and stromal-derived factor-1 (SDF-1)5, 17. Here, CCL2 is linked to neoplasm.