CXCL12 and neoplasm: Interestingly, the interaction of MSC with tumor cells modifies their trophic properties through the release of various cytokines such as CXCL1, CXCL2, CXCL12 or IL-6 and metalloproteinases (MMPs) that can degrade the extracellular matrix and promote tumor migration [15,16,17].