Importance and regulation of adult stem cell migration

Cell migration is an essential process throughout the life of vertebrates, beginning during embryonic development and continuing throughout adulthood. Stem cells have an inherent ability to migrate, that is as important as their capacity for self-renewal and differentiation, enabling them to maintain tissue homoeostasis and mediate repair and regeneration. Adult stem cells reside in specific tissue niches, where they remain in a quiescent state until called upon and activated by tissue environmental signals. Cell migration is a highly regulated process that involves the integration of intrinsic signals from the niche and extrinsic factors. Studies using three-dimensional in vitro models have revealed the astonishing plasticity of cells in terms of the migration modes employed in response to changes in the microenvironment. These same properties can, however, be subverted during the development of some pathologies such as cancer. In this review, we describe the response of adult stem cells to migratory stimuli and the mechanisms by which they sense and transduce intracellular signals involved in migratory processes. Understanding the molecular events underlying migration may help develop therapeutic strategies for regenerative medicine and to treat diseases with a cell migration component.