It has also been experimentally demonstrated that breast cancer cells that overexpress chemokine (C-X-C motif) ligand 1 (CXCL1) and 2 by transcriptional hyperactivation or 4q21 amplification display increased survival, the onset of lung metastases and enhanced chemoresistance through myeloid cell recruitment [41]. The gene discussed is CXCL1; the disease is breast carcinoma.