title: A role for cancer stem cells in therapy resistance: cellular and molecular mechanisms.
abstract: Similar to normal tissue, many tumors have a hierarchical organization where tumorigenic cancer stem cells (CSCs) differentiate into non-tumorigenic progenies. A host of studies have demonstrated that although CSCs and their non-tumorigenic progenies within the same clone can share common genotype, they display different epigenetic profiles that results in changes of multiple signaling pathways. Many of these pathways confer cell adaptation to the microenvironmental stresses including inflammation, hypoxia, low pH, shortage in nutrients and anti-cancer therapies. Treatment strategies based on combination of conventional therapies targeting bulk tumor cells and CSC-specific pathway inhibition bear a promise to improve cancer cure compared to monotherapies. In this review we describe the mechanisms of CSC-related therapy resistance including drug efflux by ABC transporters, activation of aldehyde dehydrogenase and developmental pathways, enhanced DNA damage response, autophagy and microenvironmental conditions, and discuss possible therapeutic strategies for improving cancer treatment.
authors: OncoRay-National Center for Radiation Research in Oncology, Medical Faculty and University Hospital Carl Gustav Carus, Technische Universität Dresden and Helmholtz-Zentrum Dresden-Rossendorf, Fetscherstrasse 74, 01307 Dresden, Germany.
authors: Monica
authors: M
authors: Cojoc
authors: OncoRay-National Center for Radiation Research in Oncology, Medical Faculty and University Hospital Carl Gustav Carus, Technische Universität Dresden and Helmholtz-Zentrum Dresden-Rossendorf, Fetscherstrasse 74, 01307 Dresden, Germany.
authors: Katrin
authors: K
authors: Mäbert
authors: Institute of Pathology, Medical Faculty and University Hospital Carl Gustav Carus, Technische Universität Dresden, Fetscherstrasse 74, 01307 Dresden, Germany.
authors: Michael H
authors: MH
authors: Muders
authors: OncoRay-National Center for Radiation Research in Oncology, Medical Faculty and University Hospital Carl Gustav Carus, Technische Universität Dresden and Helmholtz-Zentrum Dresden-Rossendorf, Fetscherstrasse 74, 01307 Dresden, Germany; German Cancer Consortium (DKTK) Dresden and German Cancer Research Center (DKFZ), Heidelberg, Germany. Electronic address: Anna.Dubrovska@OncoRay.de.
authors: Anna
authors: A
authors: Dubrovska
mesh_terms: D018528:ATP-Binding Cassette Transporters / Q000378:metabolism; D000970:Antineoplastic Agents / Q000378:metabolism / Q000627:therapeutic use*; D014408:Biomarkers, Tumor / Q000378:metabolism; D019008:Drug Resistance, Neoplasm; D006801:Humans; D008954:Models, Biological; D058990:Molecular Targeted Therapy / Q000379:methods; D009369:Neoplasms / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D014411:Neoplastic Stem Cells / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D015398:Signal Transduction / Q000187:drug effects
chemical_list: D018528:ATP-Binding Cassette Transporters; D000970:Antineoplastic Agents; D014408:Biomarkers, Tumor
keywords: Autophagy; Cancer stem cells; DNA repair; Hypoxia; Therapy resistance