Numerous studies have already been discussed, which highlighted the intricate interactions between resident macrophages, IL-6, COX-2/PGE2 and CXCL12 in the breast cancer microenvironment (Garcia-Tuñón et al., 2005; Martinet et al., 2010; Chow and Luster, 2014). Here, CXCL12 is linked to breast cancer.