Among the mechanisms of breast cancer cell dissemination to the BM, bone and bone marrow homing of cancer cells may depend on similar molecular determinants, especially the SDF1/CXCR4 axis.47, 48 CXCR4 is a G protein-coupled receptor,49 which plays a role in the chemotaxis of breast cancer cells. This evidence concerns the gene CXCL12 and breast carcinoma.