title: On mammary stem cells.
abstract: Mammary gland stem cells are a quiescent and self-renewing population within the mammary gland that are capable of giving rise to the differentiated ductal, alveolar and myoepithelial cells. To identify mammary gland stem cells, several investigators have employed a variety of methods including: non-adherent mammosphere cultures; 5-bromo-2-deoxy-uridine (BrdU) label-retention studies; cell-surface markers, such as Sca1 and CD49f; and Hoechst dye efflux. These methods have helped identify and further characterize signal transduction pathways such as the Notch, Wnt and Hedgehog pathways that may be important for the self-renewal and fate determination of mammary gland stem cells. Stem cells within the mammary gland have been proposed to underpin many types of breast cancer. A better understanding of the signal transduction pathways and the molecules that are responsible for the self-renewal and survival of these cells will be essential in the design of more effective therapies aimed at the eradication of both cancer-initiating cells and breast cancer stem cells.
authors.affiliation: Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030-3498, USA.
authors.forename: Wendy A
authors.initials: WA
authors.lastname: Woodward
authors.forename: Mercy S
authors.initials: MS
authors.lastname: Chen
authors.forename: Fariba
authors.initials: F
authors.lastname: Behbod
authors.forename: Jeffrey M
authors.initials: JM
authors.lastname: Rosen
mesh_terms: D000818:Animals; D001943:Breast Neoplasms / Q000209:etiology* / Q000503:physiopathology / Q000628:therapy; D002454:Cell Differentiation / Q000502:physiology*; D019070:Cell Lineage / Q000502:physiology*; D002471:Cell Transformation, Neoplastic; D005260:Female; D006801:Humans; D008321:Mammary Glands, Animal / Q000166:cytology* / Q000254:growth & development / Q000502:physiology; D042361:Mammary Glands, Human / Q000166:cytology* / Q000254:growth & development / Q000502:physiology; D015398:Signal Transduction / Q000502:physiology; D013234:Stem Cells / Q000166:cytology / Q000502:physiology*