BCL-2 inhibition with ABT-737 prolongs survival in an NRAS/BCL-2 mouse model of AML by targeting primitive LSK and progenitor cells.
Myelodysplastic syndrome (MDS) transforms into an acute myelogenous leukemia (AML) with associated increased bone marrow (BM) blast infiltration. Using a transgenic mouse model, MRP8[NRASD12/hBCL-2], in which the NRAS:BCL-2 complex at the mitochondria induces MDS progressing to AML with dysplastic features, we studied the therapeutic potential of a BCL-2 homology domain 3 mimetic inhibitor, ABT-737. Treatment significantly extended lifespan, increased survival of lethally irradiated secondary recipients transplanted with cells from treated mice compared with cells from untreated mice, with a reduction of BM blasts, Lin-/Sca-1(+)/c-Kit(+), and progenitor populations by increased apoptosis of infiltrating blasts of diseased mice assessed in vivo by technicium-labeled annexin V single photon emission computed tomography and ex vivo by annexin V/7-amino actinomycin D flow cytometry, terminal deoxynucleotidyltransferase-mediated dUTP nick end labeling, caspase 3 cleavage, and re-localization of the NRAS:BCL-2 complex from mitochondria to plasma membrane. Phosphoprotein analysis showed restoration of wild-type (WT) AKT or protein kinase B, extracellular signal-regulated kinase 1/2 and mitogen-activated protein kinase patterns in spleen cells after treatment, which showed reduced mitochondrial membrane potential. Exon specific gene expression profiling corroborates the reduction of leukemic cells, with an increase in expression of genes coding for stem cell development and maintenance, myeloid differentiation, and apoptosis. Myelodysplastic features persist underscoring targeting of BCL-2-mediated effects on MDS-AML transformation and survival of leukemic cells.
Institut National de la Santé et de la Recherche Médicale U940, Paris, France;
Stephanie
S
Beurlet
Nader
N
Omidvar
Petra
P
Gorombei
Patricia
P
Krief
Carole
C
Le Pogam
Niclas
N
Setterblad
Pierre
P
de la Grange
Christophe
C
Leboeuf
Anne
A
Janin
Maria-Elena
ME
Noguera
Florence
F
Hervatin
Laure
L
Sarda-Mantel
Marina
M
Konopleva
Michael
M
Andreeff
Andrea W
AW
Tu
Alice C
AC
Fan
Dean W
DW
Felsher
Anthony
A
Whetton
Marika
M
Pla
Robert
R
West
Pierre
P
Fenaux
Christine
C
Chomienne
Rose Ann
RA
Padua
D000818:Animals; D000950:Antigens, Ly / Q000378:metabolism; D001713:Biphenyl Compounds / Q000494:pharmacology*; D019070:Cell Lineage; D002462:Cell Membrane / Q000378:metabolism; D049109:Cell Proliferation; D002471:Cell Transformation, Neoplastic; D017690:Cell Transplantation; D004195:Disease Models, Animal; D005434:Flow Cytometry; D015973:Gene Expression Regulation, Leukemic; D015470:Leukemia, Myeloid, Acute / Q000378:metabolism*; D020935:MAP Kinase Signaling System; D008565:Membrane Proteins / Q000378:metabolism; D051379:Mice; D008822:Mice, Transgenic; D008928:Mitochondria / Q000378:metabolism; D009596:Nitrophenols / Q000494:pharmacology*; D010879:Piperazines / Q000494:pharmacology; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000037:antagonists & inhibitors / Q000378:metabolism*; D019009:Proto-Oncogene Proteins c-kit / Q000378:metabolism; D013234:Stem Cells / Q000166:cytology; D013449:Sulfonamides / Q000494:pharmacology*; D018631:ras Proteins / Q000378:metabolism*
C501332:ABT-737; D000950:Antigens, Ly; D001713:Biphenyl Compounds; C074650:Ly6a protein, mouse; D008565:Membrane Proteins; D009596:Nitrophenols; D010879:Piperazines; D019253:Proto-Oncogene Proteins c-bcl-2; D013449:Sulfonamides; D019009:Proto-Oncogene Proteins c-kit; D018631:ras Proteins