title: APO866 Increases Antitumor Activity of Cyclosporin-A by Inducing Mitochondrial and Endoplasmic Reticulum Stress in Leukemia Cells.
abstract: OBJECTIVE
  The nicotinamide phosphoribosyltransferase (NAMPT) inhibitor, APO866, has been previously shown to have antileukemic activity in preclinical models, but its cytotoxicity in primary leukemia cells is frequently limited. The success of current antileukemic treatments is reduced by the occurrence of multidrug resistance, which, in turn, is mediated by membrane transport proteins, such as P-glycoprotein-1 (Pgp). Here, we evaluated the antileukemic effects of APO866 in combination with Pgp inhibitors and studied the mechanisms underlying the interaction between these two types of agents.
  
  
  METHODS
  The effects of APO866 with or without Pgp inhibitors were tested on the viability of leukemia cell lines, primary leukemia cells (AML, n = 6; B-CLL, n = 19), and healthy leukocytes. Intracellular nicotinamide adenine dinucleotide (NAD(+)) and ATP levels, mitochondrial transmembrane potential (ΔΨ(m)), markers of apoptosis and of endoplasmic reticulum (ER) stress were evaluated.
  
  
  RESULTS
  The combination of APO866 with Pgp inhibitors resulted in a synergistic cytotoxic effect in leukemia cells, while sparing normal CD34(+) progenitor cells and peripheral blood mononuclear cells. Combining Pgp inhibitors with APO866 led to increased intracellular APO866 levels, compounded NAD(+) and ATP shortage, and induced ΔΨ(m) dissipation. Notably, APO866, Pgp inhibitors and, to a much higher extent, their combination induced ER stress and ER stress inhibition strongly reduced the activity of these treatments.
  
  
  CONCLUSIONS
  APO866 and Pgp inhibitors show a strong synergistic cooperation in leukemia cells, including acute myelogenous leukemia (AML) and B-cell chronic lymphocytic leukemia (B-CLL) samples. Further evaluations of the combination of these agents in clinical setting should be considered.
authors.affiliation: Department of Hematology and Oncology, IRCCS AOU S. Martino-IST, Genoa, Italy. Department of Medical Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts.
authors.forename: Antonia
authors.initials: A
authors.lastname: Cagnetta
authors.affiliation: Department of Hematology and Oncology, IRCCS AOU S. Martino-IST, Genoa, Italy.
authors.forename: Irene
authors.initials: I
authors.lastname: Caffa
authors.affiliation: Department of Medical Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts.
authors.forename: Chirag
authors.initials: C
authors.lastname: Acharya
authors.affiliation: Department of Hematology and Oncology, IRCCS AOU S. Martino-IST, Genoa, Italy.
authors.forename: Debora
authors.initials: D
authors.lastname: Soncini
authors.affiliation: Mount Auburn Hospital, Harvard Medical School, Cambridge, Massachusetts.
authors.forename: Prakrati
authors.initials: P
authors.lastname: Acharya
authors.affiliation: Department of Medical Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts.
authors.forename: Sophia
authors.initials: S
authors.lastname: Adamia
authors.affiliation: Department of Hematology and Oncology, IRCCS AOU S. Martino-IST, Genoa, Italy.
authors.forename: Ivana
authors.initials: I
authors.lastname: Pierri
authors.affiliation: Department of Hematology and Oncology, IRCCS AOU S. Martino-IST, Genoa, Italy.
authors.forename: Micaela
authors.initials: M
authors.lastname: Bergamaschi
authors.affiliation: Department of Hematology and Oncology, IRCCS AOU S. Martino-IST, Genoa, Italy.
authors.forename: Anna
authors.initials: A
authors.lastname: Garuti
authors.affiliation: Laboratories Department, Pathology Unit, IRCCS AUO S. Martino-IST, Genoa, Italy.
authors.forename: Giulio
authors.initials: G
authors.lastname: Fraternali
authors.affiliation: Department of Surgical and Diagnostic Sciences (DISC), Pathology Unit, IRCCS AUO S. Martino-IST, Genoa, Italy.
authors.forename: Luca
authors.initials: L
authors.lastname: Mastracci
authors.affiliation: Center for Integrative Biology, University of Trento, Trento, Italy.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Provenzani
authors.affiliation: Department of Experimental Medicine, Section of Biochemistry, and CEBR, University of Genoa, Italy.
authors.forename: Chiara
authors.initials: C
authors.lastname: Zucal
authors.affiliation: Department of Experimental Medicine, Section of Biochemistry, and CEBR, University of Genoa, Italy.
authors.forename: Gianluca
authors.initials: G
authors.lastname: Damonte
authors.affiliation: Department of Experimental Medicine, Section of Biochemistry, and CEBR, University of Genoa, Italy.
authors.forename: Annalisa
authors.initials: A
authors.lastname: Salis
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Foundation for Medical Researchers, University of Geneva, Geneva, Switzerland. Department of Medical Specialties, University of Geneva, Geneva, Switzerland.
authors.forename: Fabrizio
authors.initials: F
authors.lastname: Montecucco
authors.affiliation: Department of Hematology and Oncology, IRCCS AOU S. Martino-IST, Genoa, Italy.
authors.forename: Franco
authors.initials: F
authors.lastname: Patrone
authors.affiliation: Department of Hematology and Oncology, IRCCS AOU S. Martino-IST, Genoa, Italy.
authors.forename: Alberto
authors.initials: A
authors.lastname: Ballestrero
authors.affiliation: Department of Experimental Medicine, Section of Biochemistry, and CEBR, University of Genoa, Italy.
authors.forename: Santina
authors.initials: S
authors.lastname: Bruzzone
authors.affiliation: Department of Hematology and Oncology, IRCCS AOU S. Martino-IST, Genoa, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Gobbi
authors.affiliation: Department of Hematology and Oncology, IRCCS AOU S. Martino-IST, Genoa, Italy. michele.cea@unige.it alessio.nencioni@unige.it.
authors.forename: Alessio
authors.initials: A
authors.lastname: Nencioni
authors.affiliation: Department of Hematology and Oncology, IRCCS AOU S. Martino-IST, Genoa, Italy. Department of Medical Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts. michele.cea@unige.it alessio.nencioni@unige.it.
authors.forename: Michele
authors.initials: M
authors.lastname: Cea
mesh_terms: D018435:ATP Binding Cassette Transporter, Subfamily B / Q000037:antagonists & inhibitors / Q000378:metabolism; D000178:Acrylamides / Q000494:pharmacology*; D000255:Adenosine Triphosphate / Q000378:metabolism; D000368:Aged; D000970:Antineoplastic Agents / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D002869:Chromosome Aberrations; D016572:Cyclosporine / Q000494:pharmacology*; D019008:Drug Resistance, Neoplasm; D004357:Drug Synergism; D059865:Endoplasmic Reticulum Stress / Q000187:drug effects*; D005260:Female; D015870:Gene Expression; D006801:Humans; D007143:Immunoglobulin Heavy Chains / Q000235:genetics; D007938:Leukemia / Q000235:genetics / Q000378:metabolism* / Q000401:mortality / Q000473:pathology; D008297:Male; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D008875:Middle Aged; D008928:Mitochondria / Q000187:drug effects* / Q000378:metabolism*; D009154:Mutation; D009243:NAD / Q000378:metabolism; D009367:Neoplasm Staging; D009525:Niacin / Q000494:pharmacology; D009536:Niacinamide / Q000494:pharmacology; D054409:Nicotinamide Phosphoribosyltransferase / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D010880:Piperidines / Q000494:pharmacology*; D061251:Primary Cell Culture; D011379:Prognosis; D014407:Tumor Cells, Cultured; D056811:Unfolded Protein Response / Q000187:drug effects
chemical_list: D018435:ATP Binding Cassette Transporter, Subfamily B; D000178:Acrylamides; D000970:Antineoplastic Agents; D007143:Immunoglobulin Heavy Chains; C480543:N-(4-(1-benzoylpiperidin-4-yl)butyl)-3-(pyridin-3-yl)acrylamide; D010880:Piperidines; D009243:NAD; D009536:Niacinamide; D009525:Niacin; D016572:Cyclosporine; D000255:Adenosine Triphosphate; D054409:Nicotinamide Phosphoribosyltransferase