Cancer stem cells

Cancer stem cells (CSC) are recently proposed to be the cancer initiating cells responsible for tumorigenesis and contribute to cancer resistance. Advances have been made in identifying and enriching CSC ill leukemia and several solid tumors, including breast, brain and lung cancers. These Studies suggest that, like normal stem cells, CSCs should be rare, quiescent, and capable of self renewing and maintaining tumour growth and heterogeneity. Although the concept of CSC originates from that of normal stern cells, CSCs are not necessarily aberrant Counterparts of normal stern cells. In fact, they may arise from stein cells or committed progenitors of corresponding tissues, and even cells from other tissues. At the molecular level, the alteration of stern cell self-renewal pathway(s) has been recognized as all essential step for CSC transformation. Better understanding of CSC will no doubt lead to a new era of both basic and clinical cancer research, re-classification of human tumors and development of novel therapeutic strategies specifically targeting CSC.