title: Cancer stem cells, the epithelial to mesenchymal transition (EMT) and radioresistance: potential role of hypoxia.
abstract: Numerous studies have demonstrated the presence of cancer stem cells (CSCs) within solid tumors. Although the precursor of these cells is not clearly established, recent studies suggest that the phenotype of CSCs may be quite plastic and associated with the epithelial-to-mesenchymal transition (EMT). In patients, the presence of EMT and CSCs has been implicated in increased resistance to radiotherapy. Hypoxia, a negative prognostic factor for treatment success, is a potent driver of a multitude of molecular signalling pathways that allow cells to survive and thrive in the hostile tumor microenvironment and can induce EMT. Hypoxia also provides tumor cells with cues for maintenance of a stem-like state and may help to drive the linkage between EMT and CSCs. Understanding the biology of CSCs, the EMT phenotype and their implications in therapeutic relapse may provide crucial new approaches in the development of improved therapeutic strategies.
authors.affiliation: Ontario Cancer Institute/Princess Margaret Cancer Centre, University Health Network, Toronto, Canada; Campbell Family Institute for Cancer Research, University Health Network, Toronto, Canada; Department of Medical Biophysics, University of Toronto, Toronto, Canada.
authors.forename: Delphine Tamara
authors.initials: DT
authors.lastname: Marie-Egyptienne
authors.forename: Ines
authors.initials: I
authors.lastname: Lohse
authors.forename: Richard Peter
authors.initials: RP
authors.lastname: Hill
mesh_terms: D015687:Cell Hypoxia / Q000528:radiation effects*; D058750:Epithelial-Mesenchymal Transition / Q000528:radiation effects; D006801:Humans; D000860:Hypoxia / Q000473:pathology; D009369:Neoplasms / Q000473:pathology* / Q000532:radiotherapy*; D014411:Neoplastic Stem Cells / Q000378:metabolism / Q000473:pathology* / Q000528:radiation effects*; D011836:Radiation Tolerance; D059016:Tumor Microenvironment