CXCL12 and breast neoplasm: Mechanistically, NCOA1 has been shown to up-regulate Twist1, ITGA5, CSF-1, SDF1 and CXCR4 expression, which are partially responsible for promoting metastasis through potentiating breast tumor cell epithelial-mesenchymal transition (EMT), migration, invasion and macrophage recruitment [19, 21–23].