A Glance into Cancer Stem Cells

The presence of stem cells in leukemia and solid tumors has been demonstrated in recent decades. Cancer stem cells have the potency of tumorigenesis; furthermore, they have the ability of self-renewing and differentiation like other stem cells. They also play important role in the process of tumor invasion and metastasis. Several studies have been performed to discover the specific markers and different phenotypes of these cells that can be very important in their identification. It seems that the characteristic of cancer stem cells, like tumor genesis, is greatly related to the specific signaling pathways such as Wnt, ? catenin and hedgehog. In addition, the tumor microenvironment and its controlling agents are the important factors involving in the regulation of cancer stem cell function. The present review aimed to investigate the biology of cancer stem cells, specific signaling pathways, factors controlling the microenvironment as well as the role of microRNAs in controlling the function of these cells to provide new therapeutic methods.