title: Up-regulation of MDR1 and induction of doxorubicin resistance by histone deacetylase inhibitor depsipeptide (FK228) and ATRA in acute promyelocytic leukemia cells.
abstract: The multidrug resistance 1 (MDR1) gene product P-glycoprotein (P-gp) is frequently implicated in cross-resistance of tumors to chemotherapeutic drugs. In contrast, acute promyelocytic leukemia (APL) cells do not express MDR1 and are highly sensitive to anthracyclines. The combination of ATRA and the novel histone deacetylase inhibitor (HDACI) depsipeptide (FK228) induced P-gp expression and prevented growth inhibition and apoptosis in NB4 APL cells subsequently exposed to doxorubicin (DOX). ATRA/FK228 treatment after exposure to DOX, however, enhanced apoptosis. Both agents, ATRA or FK228, induced MDR1 mRNA. This effect was significantly enhanced by ATRA/FK228 administered in combination, due in part to increased H4 and H3-Lys9 acetylation of the MDR1 promoter and recruitment of the nuclear transcription factor Y alpha (NFYA) transcription activator to the CCAAT box. Cotreatment with specific P-gp inhibitor PSC833 reversed cytoprotective effects of ATRA/FK228. G1 cell-cycle arrest and p21 mRNA induction were also observed in response to ATRA/FK228, which may restrict DOX-induced apoptosis of cells in G2 phase. These results indicate that epigenetic mechanisms involving NF-YA transcription factor recruitment and histone acetylation are activated by ATRA and HDACI, induce MDR1 in APL cells, and point to the critical importance of mechanism-based sequential therapy in future clinical trials that combine HDAC inhibitors, ATRA, and anthracyclines.
authors.affiliation: Section of Molecular Hematology and Therapy, Department of Blood and Marrow Transplantation, Unit 448, 1515 Holcombe Boulevard, Houston, TX 77030, USA.
authors.forename: Yoko
authors.initials: Y
authors.lastname: Tabe
authors.forename: Marina
authors.initials: M
authors.lastname: Konopleva
authors.forename: Rooha
authors.initials: R
authors.lastname: Contractor
authors.forename: Mark
authors.initials: M
authors.lastname: Munsell
authors.forename: Wendy D
authors.initials: WD
authors.lastname: Schober
authors.forename: Linhua
authors.initials: L
authors.lastname: Jin
authors.forename: Yuko
authors.initials: Y
authors.lastname: Tsutsumi-Ishii
authors.forename: Isao
authors.initials: I
authors.lastname: Nagaoka
authors.forename: Jun
authors.initials: J
authors.lastname: Igari
authors.forename: Michael
authors.initials: M
authors.lastname: Andreeff
mesh_terms: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000235:genetics*; D000903:Antibiotics, Antineoplastic / Q000494:pharmacology*; D002453:Cell Cycle / Q000187:drug effects; D047630:Depsipeptides / Q000494:pharmacology*; D004317:Doxorubicin / Q000494:pharmacology*; D019008:Drug Resistance, Neoplasm / Q000502:physiology*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D019450:Genes, MDR; D056572:Histone Deacetylase Inhibitors; D006801:Humans; D015473:Leukemia, Promyelocytic, Acute / Q000235:genetics*
chemical_list: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D000903:Antibiotics, Antineoplastic; D047630:Depsipeptides; D004791:Enzyme Inhibitors; D056572:Histone Deacetylase Inhibitors; D004317:Doxorubicin; C087123:romidepsin