title: Evolving views of breast cancer stem cells and their differentiation States.
abstract: Cellular heterogeneity is a prominent characteristic of breast cancers, and accumulating evidence indicates that variability in the differentiation state of tumor cells contributes to this phenomenon. Breast cancers are among the tumor types in which the existence of cancer stem cells has been widely supported, and specific markers, including CD44/CD24 and ALDH1, have been consistently used to identify such cells. Recent studies have revealed the potential for dynamic bidirectional transitions of breast cancer cells between differentiated and stem-like phenotypes. In addition, the potential importance of intermediate states along differentiation axes, including the epithelial-to-mesenchymal transition and the basal-luminal differentiation axis, has emerged. These findings provide a view of breast cancer stem cells that departs from the traditional unidirectional hierarchical model, as well as new insights into the mechanisms by which differentiation events contribute to breast cancer biology. Herein we discuss these advances.
authors.affiliation: Department of Developmental Biology and Cancer Research, Institute for Medical Research - Israel-Canada, The Hebrew University-Hadassah Medical School, Jerusalem, Israel.
authors.forename: Reba
authors.initials: R
authors.lastname: Condiotti
authors.affiliation: Gottesman Institute for Stem Cell and Regenerative Medicine Research, Department of Cell Biology, Albert Einstein College of Medicine, New York, New York.
authors.forename: Wenjun
authors.initials: W
authors.lastname: Guo
authors.affiliation: Department of Developmental Biology & Cancer Research Institute for Medical Research - Israel-Canada; The Hebrew University-Hadassah Medical School Jerusalem, Israel.
authors.forename: Ittai
authors.initials: I
authors.lastname: Ben-Porath
mesh_terms: D001943:Breast Neoplasms / Q000473:pathology*; D002454:Cell Differentiation; D058750:Epithelial-Mesenchymal Transition; D006801:Humans; D014411:Neoplastic Stem Cells / Q000473:pathology*