CXCL12 and breast cancer: In addition, miR-126/miR-126* directly inhibits chemokine C–X–C motif ligand 12 (CXCL12) and indirectly suppresses chemokine C–C motif ligand 2 (CCL2) in a CXCL12-dependent manner, thereby blocking the recruitment of MSCs and inflammatory monocytes to the tumor microenvironment and reducing the lung metastatic potential of breast cancer [35].