CXCL12 and neoplasm: MSCs have been shown to release factors such as VEGF, FGF-2, PDGF, HGF, BDNF, SDF-1α, IGF-1, IGF-2, TGF-β, TNFα IGFBP-2, LIF, M-CSF, MIP-2, IL-8, IL-6, and IFNγ that promote tumour survival, proliferation, migration, invasion [21,43,44,45,46,47], and angiogenesis [21,24,25,33,48,49,50,51,52].