title: The clinical and therapeutic implications of cancer stem cell biology.
abstract: Cancer stem cells (CSCs) have provided new insights into the tumorigenesis and metastatic potential of cancer. The discovery of CSCs has provided many new insights into the complexities of cancer therapy: tumor initiation, treatment resistance, metastasis, recurrence, assessment of prognosis and prediction of clinical course. Recent rapid advances in molecular analysis have contributed to the better understanding of the molecular attributes and pathways that give CSCs their unique attributes. Use of these molecular techniques has facilitated elucidation of specific surface markers and pathways that favor propagation of CSCs - allowing for targeted therapy. Furthermore, it has been discovered that a specific microenvironment, or niche, is essential for the genesis of tumors from CSCs. Therapeutic strategies that alter these microenvironments compromise CSC proliferation and constitute another method of targeted cancer therapy. We review the clinical and therapeutic implications of CSCs, with a focus on treatment resistance and metastasis, and the emerging approaches to target CSCs and their microenvironments in order to attain improved outcomes in cancer. It is noteworthy that CSCs are the only cells capable of sustaining tumorigenesis; however, the cell of origin of cancer, in which tumorigenesis is initiated, may be distinct from CSCs that propagate the tumor.
authors.affiliation: Department of Pathology, Indiana University School of Medicine, 350 West 11th Street, Room 4010, Indianapolis, IN 4620, USA. liang_cheng@yahoo.com
authors.forename: Liang
authors.initials: L
authors.lastname: Cheng
authors.forename: Riley
authors.initials: R
authors.lastname: Alexander
authors.forename: Shaobo
authors.initials: S
authors.lastname: Zhang
authors.forename: Chong-Xian
authors.initials: CX
authors.lastname: Pan
authors.forename: Gregory T
authors.initials: GT
authors.lastname: MacLennan
authors.forename: Antonio
authors.initials: A
authors.lastname: Lopez-Beltran
authors.forename: Rodolfo
authors.initials: R
authors.lastname: Montironi
mesh_terms: D002471:Cell Transformation, Neoplastic / Q000187:drug effects* / Q000473:pathology; D019008:Drug Resistance, Neoplasm / Q000502:physiology; D006801:Humans; D009362:Neoplasm Metastasis / Q000503:physiopathology / Q000628:therapy*; D009369:Neoplasms / Q000473:pathology / Q000628:therapy*; D014411:Neoplastic Stem Cells / Q000187:drug effects* / Q000473:pathology