Stem cells in cancer therapy: From their role in pathogenesis to their use as therapeutic agents.

Advances in the understanding of the intriguing properties of stem cells are prompting the development of new therapeutic approaches in oncology. Stemness is a crucial condition for the homeostasis of the human body. Nevertheless, pathways that regulate self-renewal and cell fate of normal stem cells, such as Wnt and hedgehog, are also involved in the regulation of cancer stem cells and tumor growth and progression, and may thus represent novel therapeutic targets in cancer treatment. In addition, the ability of stem cells to self-renew, migrate to tumor sites and differentiate into multiple cell types makes them perfect candidates for being used as tools for delivering therapeutic genes and proteins and as drug vectors to eliminate malignant cells.