CXCL12 and breast carcinoma: The inhibition of PDGFRα by PDGFRα inhibitors and NT21MP attenuated the SDF-1α-stimulated phosphorylation of AKT and ERK1/2 and breast cancer cell migration and had a synergistic effect compared with single treatment with either NT21MP or PDGFR inhibitor (Figure 8A, 8C).