title: Acetazolamide potentiates the anti-tumor potential of HDACi, MS-275, in neuroblastoma.
abstract: Neuroblastoma (NB), a tumor of the primitive neural crest, despite aggressive treatment portends a poor long-term survival for patients with advanced high stage NB. New treatment strategies are required.
  
  
  
  We investigated coordinated targeting of essential homeostatic regulatory factors involved in cancer progression, histone deacetylases (HDACs) and carbonic anhydrases (CAs).
  
  
  
  We evaluated the antitumor potential of the HDAC inhibitor (HDACi), pyridylmethyl-N-{4-[(2-aminophenyl)-carbamoyl]-benzyl}-carbamate (MS-275) in combination with a pan CA inhibitor, acetazolamide (AZ) on NB SH-SY5Y, SK-N-SH and SK-N-BE(2) cells. The key observation was that the combination AZ + MS-275 significantly inhibited growth, induced cell cycle arrest and apoptosis, and reduced migration capacity of NB cell line SH-SY5Y. In addition, this combination significantly inhibited tumor growth in vivo, in a pre-clinical xenograft model. Evidence was obtained for a marked reduction in tumorigenicity and in the expression of mitotic, proliferative, HIF-1α and CAIX. NB xenografts of SH-SY5Y showed a significant increase in apoptosis.
  
  
  
  MS-275 alone at nanomolar concentrations significantly reduced the putative cancer stem cell (CSC) fraction of NB cell lines, SH-SY5Y and SK-N-BE(2), in reference to NT2/D1, a teratocarcinoma cell line, exhibiting a strong stem cell like phenotype in vitro. Whereas stemness genes (OCT4, SOX2 and Nanog) were found to be significantly downregulated after MS-275 treatment, this was further enhanced by AZ co-treatment. The significant reduction in initial tumorigenicity and subsequent abrogation upon serial xenografting suggests potential elimination of the NB CSC fraction. The significant potentiation of MS-275 by AZ is a promising therapeutic approach and one amenable for administration to patients given their current clinical utility.
authors.affiliation: Developmental and Stem Cell Biology, The Hospital for Sick Children, Toronto, ON, Canada. reza.mokhtari@sickkids.ca.|Department of Paediatric Laboratory Medicine, The Hospital for Sick Children, Toronto, ON, Canada. reza.mokhtari@sickkids.ca.|Institute of Medical Science, University of Toronto, Toronto, ON, Canada. reza.mokhtari@sickkids.ca.|Department of Immunology and Infectious Diseases, The Forsyth Institute, Cambridge, MA, USA. reza.mokhtari@sickkids.ca.
authors.forename: Reza
authors.initials: R
authors.lastname: Bayat Mokhtari
authors.affiliation: Department of Pathology and Molecular Medicine, Queen's University, Kingston, ON, Canada.
authors.forename: Narges
authors.initials: N
authors.lastname: Baluch
authors.affiliation: Developmental and Stem Cell Biology, The Hospital for Sick Children, Toronto, ON, Canada.
authors.forename: Micky
authors.initials: M
authors.lastname: Ka Hon Tsui
authors.affiliation: Developmental and Stem Cell Biology, The Hospital for Sick Children, Toronto, ON, Canada.
authors.forename: Sushil
authors.initials: S
authors.lastname: Kumar
authors.affiliation: Developmental and Stem Cell Biology, The Hospital for Sick Children, Toronto, ON, Canada.
authors.forename: Tina
authors.initials: T
authors.lastname: S Homayouni
authors.affiliation: Developmental and Stem Cell Biology, The Hospital for Sick Children, Toronto, ON, Canada.
authors.forename: Karen
authors.initials: K
authors.lastname: Aitken
authors.affiliation: Department of Immunology and Infectious Diseases, The Forsyth Institute, Cambridge, MA, USA.
authors.forename: Bikul
authors.initials: B
authors.lastname: Das
authors.affiliation: Department of Paediatrics, Division of Hematology/Oncology, The Hospital for Sick Children, Toronto, ON, Canada.
authors.forename: Sylvain
authors.initials: S
authors.lastname: Baruchel
authors.affiliation: Developmental and Stem Cell Biology, The Hospital for Sick Children, Toronto, ON, Canada. hermie@sickkids.ca.|Department of Paediatric Laboratory Medicine, The Hospital for Sick Children, Toronto, ON, Canada. hermie@sickkids.ca.|Institute of Medical Science, University of Toronto, Toronto, ON, Canada. hermie@sickkids.ca.
authors.forename: Herman
authors.initials: H
authors.lastname: Yeger
mesh_terms: D000086:Acetazolamide / Q000494:pharmacology* / Q000627:therapeutic use; D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology* / Q000627:therapeutic use; D017209:Apoptosis / Q000187:drug effects*; D001549:Benzamides / Q000494:pharmacology* / Q000627:therapeutic use; D002257:Carbonic Anhydrase Inhibitors / Q000494:pharmacology / Q000627:therapeutic use; D002460:Cell Line; D002465:Cell Movement / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D004359:Drug Therapy, Combination; D005260:Female; D056572:Histone Deacetylase Inhibitors / Q000494:pharmacology / Q000627:therapeutic use; D006801:Humans; D051379:Mice; D009447:Neuroblastoma / Q000188:drug therapy*; D011725:Pyridines / Q000494:pharmacology* / Q000627:therapeutic use; D016896:Treatment Outcome; D023041:Xenograft Model Antitumor Assays
chemical_list: D000970:Antineoplastic Agents; D001549:Benzamides; D002257:Carbonic Anhydrase Inhibitors; D056572:Histone Deacetylase Inhibitors; D011725:Pyridines; C118739:entinostat; D000086:Acetazolamide
keywords: Acetazolamide; Carbonic anhydrases; HDAC inhibitor; Histone deacetylases; MS-275; Neuroblastoma