title: Blockade of mitogen-activated protein kinase/extracellular signal-regulated kinase kinase and murine double minute synergistically induces Apoptosis in acute myeloid leukemia via BH3-only proteins Puma and Bim.
abstract: Molecular aberrations of the Ras/Raf/mitogen-activated protein kinase/extracellular signal-regulated kinase (ERK) kinase (MEK)/ERK and/or Murine double minute (MDM2)/p53 signaling pathways have been reported in 80% and 50% of primary acute myeloid leukemia (AML) samples and confer poor outcome. In this study, antileukemic effects of combined MEK inhibition by AZD6244 and nongenotoxic p53 activation by MDM2 antagonist Nutlin-3a were investigated. Simultaneous blockade of MEK and MDM2 signaling by AZD6244 and Nutlin-3a triggered synergistic proapoptotic responses in AML cell lines [combination index (CI) = 0.06 +/- 0.03 and 0.43 +/- 0.03 in OCI/AML3 and MOLM13 cells, respectively] and in primary AML cells (CI = 0.52 +/- 0.01). Mechanistically, the combination upregulated levels of BH3-only proteins Puma and Bim, in part via transcriptional upregulation of the FOXO3a transcription factor. Suppression of Puma and Bim by short interfering RNA rescued OCI/AML3 cells from AZD/Nutlin-induced apoptosis. These results strongly indicate the therapeutic potential of combined MEK/MDM2 blockade in AML and implicate Puma and Bim as major regulators of AML cell survival.
authors.affiliation: Section of Molecular Hematology and Therapy, Department of Stem Cell Transplantation and Cellular Therapy, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030-4009, USA.
authors.forename: Weiguo
authors.initials: W
authors.lastname: Zhang
authors.forename: Marina
authors.initials: M
authors.lastname: Konopleva
authors.forename: Jared K
authors.initials: JK
authors.lastname: Burks
authors.forename: Karen C
authors.initials: KC
authors.lastname: Dywer
authors.forename: Wendy D
authors.initials: WD
authors.lastname: Schober
authors.forename: Jer-Yen
authors.initials: JY
authors.lastname: Yang
authors.forename: Teresa J
authors.initials: TJ
authors.lastname: McQueen
authors.forename: Mien-Chie
authors.initials: MC
authors.lastname: Hung
authors.forename: Michael
authors.initials: M
authors.lastname: Andreeff
mesh_terms: D000208:Acute Disease; D017209:Apoptosis / Q000187:drug effects / Q000502:physiology; D051017:Apoptosis Regulatory Proteins / Q000378:metabolism*; D000072224:Bcl-2-Like Protein 11; D001562:Benzimidazoles / Q000494:pharmacology; D004357:Drug Synergism; D048049:Extracellular Signal-Regulated MAP Kinases / Q000037:antagonists & inhibitors* / Q000378:metabolism; D000071316:Forkhead Box Protein O3; D051858:Forkhead Transcription Factors / Q000378:metabolism; D018922:HL-60 Cells; D006801:Humans; D007093:Imidazoles / Q000494:pharmacology; D007951:Leukemia, Myeloid / Q000188:drug therapy* / Q000201:enzymology* / Q000378:metabolism / Q000473:pathology; D020935:MAP Kinase Signaling System / Q000187:drug effects; D008565:Membrane Proteins / Q000378:metabolism*; D064549:Myeloid Cell Leukemia Sequence 1 Protein; D010766:Phosphorylation; D010879:Piperazines / Q000494:pharmacology; D011518:Proto-Oncogene Proteins / Q000378:metabolism*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism; D051736:Proto-Oncogene Proteins c-mdm2 / Q000037:antagonists & inhibitors* / Q000378:metabolism; D020298:U937 Cells
chemical_list: C517975:AZD 6244; D051017:Apoptosis Regulatory Proteins; C438378:BBC3 protein, human; C000606775:BCL2L11 protein, human; D000072224:Bcl-2-Like Protein 11; D001562:Benzimidazoles; C499517:FOXO3 protein, human; D000071316:Forkhead Box Protein O3; D051858:Forkhead Transcription Factors; D007093:Imidazoles; D008565:Membrane Proteins; D064549:Myeloid Cell Leukemia Sequence 1 Protein; D010879:Piperazines; D011518:Proto-Oncogene Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; C482205:nutlin 3; C497206:MDM2 protein, human; D051736:Proto-Oncogene Proteins c-mdm2; D048049:Extracellular Signal-Regulated MAP Kinases