CXCR4 signaling in the regulation of stem cell migration and development

The regulated migration of stein cells is a feature of the development of all tissues and also of a number of pathologies. In the former situation the migration of stem cells over large distances is required for the correct formation of the embryo. In addition, stern cells are deposited in niche like regions in adult tissues where they call be called upon for tissue regeneration and repair. The migration of cancer stern cells is a feature of the metastatic nature of this disease. In this article we discuss observations that have demonstrated the important role of chemokine signaling in the regulation of stem cell migration in both normal and pathological situations. It has been demonstrated that the chemokine receptor CXCR4 is expressed in numerous types of embryonic and adult stern cells and the chemokine SDF-1/CXCL12 has chemoattractant effects oil these cells. Animals in which SDF-1/CXCR4 signaling has been interrupted exhibit numerous phenotypes that call be explained as resulting from inhibition of SDF-1 mediated chemoattraction of stem cells. Hence, CXCR4 signaling is a key element ill understanding the functions of stem cells ill normal development and in diverse pathological situations. Published by Elsevier B.V.