MicroRNA reins in embryonic and cancer stem cells.

MicroRNAs represents a new layer of gene regulation in stem cells by controlling the molecular mechanisms involved in modulating stem cell fate and behavior. Such a role of microRNA is seen in embryonic stem cell as well, maintaining a delicate balance between survival, proliferation, and self-renewal signals. Further, dysregulation of stem cell self-renewal is a likely requirement for the initiation and formation of cancer stem cells that probably pose resistance to current cancer treatments. In fact, the precise mechanism that regulates embryonic as well as cancer stem cell self-renewal and pluripotency remains largely unknown. Understanding the miRNA related stem cell biology and pathways offers great promise for improving stem cell mediated regenerative therapy as well as cancer therapies. Here we summarize some of the emerging evidences demonstrating the role of these molecular switches in embryonic and cancer stem cells.