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NEOPLASIA
From the Department of Hematology and Oncology and the
Department of Pathology, Graduate School of Medicine, University of
Tokyo, Tokyo, Japan.
The AML1 gene encodes a DNA-binding protein that
contains the runt domain and is the most frequent target of
translocations associated with human leukemias. Here, point mutations
of the AML1 gene, V105ter (single-letter amino acid
code) and R139G, (single-letter amino acid codes)
were identified in 2 cases of myelodysplastic syndrome (MDS) by means
of the reverse transcriptase-polymerase chain reaction single-strand
conformation polymorphism method. Both mutations are present in the
region encoding the runt domain of AML1 and cause
loss of the DNA-binding ability of the resultant products. Of these
mutants, V105ter has also lost the ability to heterodimerize with
polyomavirus enhancer binding protein 2/core binding factor The human AML1 gene was first identified
on chromosome 21 as the gene that is disrupted in the (8;21)(q22;q22)
translocation; this is one of the most frequent chromosome
abnormalities associated with human acute myelogeneous leukemia
(AML).1,2 In t(8;21)(q22;q22), the rearrangement results
in the production of the AML1/MTG8 (ETO) fusion
protein.3-5 We and another group previously reported that the AML1 gene is also disrupted in t(3;21)(q26;q22), which
is found in the blastic crisis phase of chronic myelogeneous leukemia and therapy-related AML.6-10 Furthermore, it was reported
that the AML1 gene is rearranged in acute lymphoblastic
leukemia carrying t(12;21)(p12;q22).11-14
PEBP2 Recently, somatic point mutations of the AML1
gene were demonstrated in patients with AMLs.29 This
indicates that the structural alterations of AML1 caused by
non-translocation-generated mutations may also play a role in
leukemogenesis. Furthermore, it was reported that haploinsufficiency of
AML1 caused by the mutations of the AML1 gene in one allele
results in familial thrombocytopenia with propensity to develop
AML.30 However, no mutations have been described in
sporadic cases of preleukemic diseases. Myelodysplastic syndrome (MDS)
is a preleukemic state in which multistep progression to AML is
documented by serial acquisition of genetic abnormalities associated
with progression of disease.31,32 Here, among 37 cases of
MDS, we have identified 2 mutations of the AML1 gene in the
region encoding the runt domain. One patient exhibited a frame-shift
mutation resulting in termination in the middle of the runt domain of
AML1. The other has a missense mutation that causes a single amino acid
change in the adenosine triphosphate (ATP)-binding motif in the runt
domain. Both mutants have lost the ability to activate transcription of
target genes. Furthermore, we have found that the latter mutant acts as
a dominant negative inhibitor of wild-type AML1 by competing for
interaction with PEBP2 Patients and cell preparation
Reverse transcriptase-polymerase chain reaction-single-strand
conformation polymorphism
Plasmid constructions The pME-AML1 and pME-PEBP2 /CBF plasmids were constructed
by ligation of human AML1 and mouse PEBP2/CBF cDNAs,
respectively, to the pME18S expression vector as described
previously.18 For tagging AML1 at the N-terminus, the
FLAG octapeptide (DYKDDDDK) was inserted after the first
methionine by PCR as described previously.36 To generate
the FLAG-tagged constructs of AML1 mutants, we replaced the
EcoRI-BamHI fragment of pME-AML1-FLAG with the
corresponding fragment derived from cDNAs of the patients. A reporter
plasmid containing an M-CSF receptor promoter (pM-CSF-R-luc) and a
neutrophil elastase promoter (pNE-luc) were described
elsewhere.19,21
Cell culture and DNA transfection COS-7 and HeLa cells were grown in a 5% CO2 environment in Dulbecco's modified Eagle's medium (DMEM) supplemented with penicillin/streptomycin and 10% fetal calf serum (FCS). COS-7 cells were transfected with expression plasmids by the DEAE-dextran method as described previously.37 HeLa cells were transfected with expression and reporter plasmids by the calcium phosphate-DNA method as described previously.38Transient transfections and transcriptional response assays Luciferase assays were performed as described previously.18 Briefly, reporter and expression plasmids were transfected into HeLa cells by the calcium phosphate-DNA method. For analysis of luciferase activities observed in cotransfection with several expression plasmids, the equivalent-molar plasmid DNAs were transfected, and the total amount of DNA in terms of weight was adjusted to be equal by adding the plasmid pUC13. HeLa cells were cultured in DMEM containing 10% FCS for 30 to 36 hours, then harvested and subjected to the luciferase assay. The data were normalized with the use of the internal control of transfection efficiency, as described previously.39Electrophoretic mobility shift assay Nuclear extracts were obtained from COS-7 cells transfected with the corresponding cDNAs in pME18S by the DEAE-dextran method. The procedures for electrophoretic mobility shift assay (EMSA) were described previously.18 The M4 probe, which includes a partial A core of the polyomavirus enhancer and a mutated PEBP4 site (the introduced mutation abolishes the binding of PEBP4), was produced by annealing oligonucleotides 5'-GATCTAACTGACCGCAGCTGTCAGTGCGAG-3' and 5'-GATCCTCGCACTGACAGCTGCGGTCAGTTA-3'.40 The M24 probe, in which the sequence of the PEBP2 site in the M4 probe was changed to one different from the PEBP2 consensus sequence, was obtained by annealing oligonucleotides 5'-GATCTAACTCACGGCAGCTGTCAGTGCGAG-3' and 5'-GATCCTCGCACTGACAGCTGCCGTGAGTTA-3'. For radioisotope labeling, [ -32P]deoxycytidine triphosphate was
incorporated into the probes by incubation with Klenow fragment.
In vivo binding assays We coexpressed FLAG-tagged AML1 or AML1 mutants together with PEBP2/CBF in COS-7 cells. The COS-7 cells were lysed by the lysis
buffer (10 mmol/L Tris-HCl, pH 7.4; 5 mmol/L EDTA; 150 mmol/L NaCl; 1%
Triton-X; 10% glycerol; 10 U/mL aprotinin; 2 mmol/L
phenylmethylsulfonyl fluoride; 1 mmol/L Na3VO4;
5 µg/mL leupeptin; 1 µg/mL pepstatin A; 2 mmol/L benzamidine; 1 µg/mL antipain; 1 µg/mL chymostatin; and 2 µg/mL soybean trypsin
inhibitor). These cell lysates were precleared by protein G-sepharose
(Pharmacia, Uppsala, Sweden), mixed with the anti-FLAG M2 monoclonal
antibody (Sigma, St Louis, MO), and rotated for 3 hours; this was
followed by recovery of the FLAG-tagged protein on protein G-sepharose
beads. The beads were washed 4 times with the lysis buffer.
Immunoprecipitates were subjected to sodium dodecyl
sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and Western
blotting with the anti-PEBP2/CBF antibody. The
anti-PEBP2/CBF antibody was prepared as described
elsewhere.18,41
In vitro binding assays The COS-7 cells expressing wild-type or mutant AML1 were lysed by the lysis buffer described above. The cell lysates containing the same amount of wild-type or mutant AML1 were incubated with those containing PEBP2/CBF in the same lysis buffer for 2 hours. These
cell lysates were precleared by protein G-sepharose, mixed with the
anti-FLAG M2 monoclonal antibody, and rotated for 3 hours; this was
followed by recovery of the FLAG-tagged protein on protein G-sepharose
beads. The beads were washed 4 times with the lysis buffer.
Immunoprecipitates were subjected to SDS-PAGE and Western blotting with
the anti-PEBP2/CBF antibody.
Frameshift and missense mutations of the AML1 gene We screened 37 MDS patients for mutations in 4 exons (exons 3, 4, 5, and 6) of the AML1 gene, which include the runt domain, using the RT-PCR-SSCP and sequencing analyses. The specific subtypes of MDS analyzed and their relative frequency are summarized in Table 1. Abnormally migrating bands were detected on the RT-PCR-SSCP analyses in 2 patients with MDS; 1 was a patient with chronic myelomonocytic leukemia (CMMoL) and the other was a patient with AML secondary to refractory anemia (RA) (Figure 1). The sequencing analyses showed nucleotide alterations of the AML1 gene in exon 4 in both patients. The mutation found in the patient with CMMoL was a GT insertion at codon 105 resulting in V105 termination (V105) (single-letter amino acid code) (Figure 2). The other patient had a missense mutation at codon 139 (CGA to GGA), which leads to a change of amino acid, R139G (single-letter amino acid code) (Figure 2). From the sample of the patient with CMMoL, the normal and the mutated sequences were obtained, conforming to the results from the RT-PCR-SSCP analysis, in which both normally and abnormally migrating bands were detected. On the other hand, the RT-PCR-SSCP analysis of the other MDS patient showed abnormally migrating bands exclusively. Consistently, only the abnormal sequence was obtained from sequencing of the PCR product. These results suggest that an allelic loss of the runt-domain-encoding region also exists in this patient. To determine whether the AML1 gene is mutated at the germ line or the somatic level, we examined the genomic DNA sequences of the formalin-fixed and paraffin-embedded specimen of the rectum from the patient with CMMoL and the lung and liver from the patient with AML secondary to RA. Both of the genomic DNA sequences examined were normal; this reveals that the AML1 mutations are somatic events (data not shown).
AML1 mutants found in patients with MDS lack transcriptional activities AML1 has been shown to regulate expression of several hematopoietic-lineage-specific genes by affecting transcription from the cognate promoters or enhancers.19,42-46 To elucidate functional alterations of AML1 in preleukemic states, we investigated transcriptional activities of the AML1 mutants found in MDS. Previous studies show that coexpression of AML1 and its heterodimeric partner PEBP2/CBF can activate the M-CSF receptor promoter in
transcriptional response assays.21 When AML1 and
PEBP2/CBF were cotransfected with a reporter plasmid containing
an M-CSF receptor promoter into HeLa cells, there was a 4-fold
induction of the promoter activity (Figure
3A, lane 2). On the other hand, when the
V105ter or the R139G mutant was cotransfected with PEBP2/CBF,
there was no induction of the promoter activity (Figure 3A, lane 3, 4).
AML1 and its mutants were expressed with PEBP2/CBF at comparable levels in each transfection (Figure 3A). These results indicate that
those 2 mutants of AML1 found in MDS lack transcriptional activities.
Furthermore, we investigated whether these mutants act as a dominant
negative inhibitor of wild-type AML1. It is known that AML1 activates
transcription from the neutrophil elastase (NE) promoter that includes
a potential binding site for AML1.19 Concomitant
expression of the V105ter mutant with wild-type AML1 did not affect
transcriptional activation of the NE promoter induced by wild-type AML1
(data not shown). In contrast, the R139G mutant represses the
transcriptional activity of wild-type AML1 in a dose-dependent manner
(Figure 3B). The expression level of AML1 is invariable in each
transfection (Figure 3B). Although the physiological significance of
these overexpression experiments should be interpreted carefully, these
results suggest that R139G could act as a dominant negative inhibitor
for AML1.
Analyses of DNA binding of the AML1 mutants The runt domain of AML1 is reported to be responsible for binding to the PEBP2/CBF site, which is a consensus DNA sequence for AML1 binding.43,47 In a previous study, we demonstrated that AML1 specifically binds to the PEBP2/CBF site and that the DNA binding is required for AML1-induced transactivation.18 We next investigated the DNA-binding affinity of the AML1 mutants obtained from patients with MDS by means of EMSA. For this assay, a double-stranded oligonucleotide containing the PEBP2/CBF site was used as a probe (M4 probe).37 When this probe was incubated and electrophoresed with nuclear extracts from COS-7 cells containing wild-type AML1, we observed a significantly shifted band (Figure 4, lane 2), which is not seen in the control lane derived from mock-transfected cells (Figure 4, lane 1). This band was not detected when we used a mutant probe, M24, in which the PEBP2/CBF site was changed to a sequence different from the consensus sequence (Figure 4, lane 3). On the other hand, no band was detected when the M4 probe was incubated and electrophoresed with nuclear extracts containing the V105ter or the R139G mutant (Figure 4, lane 4, 6). Because a large amount of endogeneous PEBP2/CBF
should accumulate in the nucleus of COS-7 cells where AML1 is
overexpressed, these results indicate that V105ter and R139G fail to
bind to the PEBP2 site even in the presence of PEBP2/CBF. These
findings account for loss of the transcriptional activity of these 2 mutants in the transcriptional response assays. Furthermore, we
evaluated the affinity of wild-type AML1 to DNA when it is coexpressed
with each AML1 mutant in COS-7 cells. The DNA-binding ability of
wild-type AML1 was not affected when the V105ter mutant was coexpressed (Figure 4, lane 8). However, when the R139G mutant was coexpressed with
wild-type AML1, there was a marked reduction of the DNA-binding ability
of wild-type AML1 (Figure 4, lane 9). These results suggest that the
R139G mutant blocks binding of wild-type AML1 to the PEBP2/CBF site.
Because AML1-induced transcription from the M-CSF receptor or the NE
promoter is dependent on binding to the PEBP2 site, these findings are
compatible with the results that the R139G mutant acts as a dominant
negative inhibitor of wild-type AML1 in the transcriptional response
assays.19-21
The R139G mutant binds to
PEBP2 /CBF, which does
not have a DNA-binding ability per se, and heterodimerization with
PEBP2/CBF enhances the DNA-binding ability of AML1, resulting in
enhanced transactivational potency of the AML1-PEBP2/CBF complex.48 Thus, association with PEBP2/CBF is one
of the key determinants for AML1 functions. In these lines, we
previously demonstrated that chimeric products of AML1 in t(8;21) and
t(3;21) leukemias inhibit the transcriptional activity of AML1 by
sequestering PEBP2/CBF from AML1.41 Therefore, we
investigated heterodimerizing properties of the AML1 mutants that we
have identified in the patients with MDS. We coexpressed FLAG-tagged
forms of wild-type AML1, V105ter, or R139G together with
PEBP2/CBF in COS-7 cells. PEBP2/CBF was
coimmunoprecipitated with wild-type AML1 by the anti-FLAG antibody
(Figure 5A, lane 2). In contrast,
PEBP2/CBF was not detected in the coprecipitates of V105ter
(Figure 5A, lane 3). On the other hand, PEBP2/CBF was
coimmunoprecipitated with the R139G mutant (Figure 5A, lane 4). These
results show that V105ter has lost the ability to heterodimerize with
PEBP2/CBF while R139G can associate with PEBP2/CBF. In
these coimmunoprecipitation assays, PEBP2/CBF was apparently
coimmunoprecipitated with R139G more efficiently than with wild-type
AML1. To compare the abilities of heterodimerization with
PEBP2/CBF between wild-type AML1 and the R139G mutant more
precisely, we used an in vitro binding assay. The COS-7 cell lysates
containing the same amount of FLAG-tagged forms of wild-type AML1 or
the R139G mutant were incubated with the COS-7 cell lysates containing
the same amount of PEBP2/CBF. The resultant lysates were
subjected to immunoprecipitation with the anti-FLAG antibody followed
by recovery on protein G-sepharose. Amounts of these proteins were
confirmed by Western blotting of the corresponding lysates (Figure
6, middle and bottom). As shown in Figure
6, PEBP2/CBF was coimmunoprecipitated with the R139G mutant more
efficiently than with wild-type AML1. These data indicate that the
R139G mutant, having an enhanced binding affinity with PEBP2/CBF,
competes with wild-type AML1 for heterodimerization with
PEBP2/CBF, resulting in reduced DNA-binding and transactivational ability of wild-type AML1.
We analyzed the AML1 gene in patients with MDS by the
RT-PCR-SSCP method and found 2 mutations of the AML1 gene
among 37 patients. In a previous study, sporadic point mutations were
found in the AML1 gene of the patients with
AML.29 These mutations all clustered in the runt domain.
In addition, other genes containing the runt domain, such as
PEBP2 Both of the AML1 mutants found in patients with MDS in our study lack
the transcriptional activity through the M-CSF receptor or the NE
promoter assessed by the overexpression experiments. It is shown that
the runt domain of AML1 is responsible for DNA binding and
interaction with PEBP2 A recent study of the crystal structure of AML1 suggests that 3 distinct regions of the runt domain should be involved in DNA
binding.54 One of them is the In the present study, the RT-PCR-SSCP and sequencing analyses showed that the V105ter mutation was heterozygous. We obtained V105ter from a case with CMMoL, in which nearly 30% of the mononuclear cells of the bone marrow of the case were leukemic cells when the sample was obtained. On the other hand, the examination of the germ-line tissue revealed that the AML1 mutations represent somatic events. Therefore, it remains elusive whether the normal allele detected in the case with CMMoL is derived from the leukemic cells or nonleukemic cells. Our study is the first report that describes mutations of the AML1 gene in patients with MDS. It provides important insights into the molecular basis for dominant negative inhibition of AML1 and leukemogenesis derived from dysfunction of AML1.
The authors thank Dr Y. Ito for providing the cDNA of mouse
PEBP2
Submitted March 1, 2000; accepted June 27, 2000.
Supported in part by Grants-in-Aid for Cancer Research from the Ministry of Education, Science, and Culture of Japan.
The publication costs of this article were defrayed in part by page charge payment. Therefore, and solely to indicate this fact, this article is hereby marked "advertisement" in accordance with 18 U.S.C. section 1734.
Reprints: Hisamaru Hirai, Dept of Hematology and Oncology, Graduate School of Medicine, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan.
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  S. D. Nimer Myelodysplastic syndromes Blood, May 15, 2008; 111(10): 4841 - 4851. [Abstract] [Full Text] [PDF]
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N. Watanabe-Okochi, J. Kitaura, R. Ono, H. Harada, Y. Harada, Y. Komeno, H. Nakajima, T. Nosaka, T. Inaba, and T. Kitamura AML1 mutations induced MDS and MDS/AML in a mouse BMT model Blood, April 15, 2008; 111(8): 4297 - 4308. [Abstract] [Full Text] [PDF]
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 M. Ichikawa, S. Goyama, T. Asai, M. Kawazu, M. Nakagawa, M. Takeshita, S. Chiba, S. Ogawa, and M. Kurokawa AML1/Runx1 Negatively Regulates Quiescent Hematopoietic Stem Cells in Adult Hematopoiesis J. Immunol., April 1, 2008; 180(7): 4402 - 4408. [Abstract] [Full Text] [PDF]
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 D. Li, K. K. Sinha, M. A. Hay, C. R. Rinaldi, Y. Saunthararajah, and G. Nucifora RUNX1-RUNX1 Homodimerization Modulates RUNX1 Activity and Function J. Biol. Chem., May 4, 2007; 282(18): 13542 - 13551. [Abstract] [Full Text] [PDF]
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 J. Cammenga, B. Niebuhr, S. Horn, U. Bergholz, G. Putz, F. Buchholz, J. Lohler, and C. Stocking RUNX1 DNA-Binding Mutants, Associated with Minimally Differentiated Acute Myelogenous Leukemia, Disrupt Myeloid Differentiation Cancer Res., January 15, 2007; 67(2): 537 - 545. [Abstract] [Full Text] [PDF]
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M. Nakagawa, M. Ichikawa, K. Kumano, S. Goyama, M. Kawazu, T. Asai, S. Ogawa, M. Kurokawa, and S. Chiba AML1/Runx1 rescues Notch1-null mutation-induced deficiency of para-aortic splanchnopleural hematopoiesis Blood, November 15, 2006; 108(10): 3329 - 3334. [Abstract] [Full Text] [PDF]
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V. Hamelin, C. Letourneux, P.-H. Romeo, F. Porteu, and M. Gaudry Thrombopoietin regulates IEX-1 gene expression through ERK-induced AML1 phosphorylation Blood, April 15, 2006; 107(8): 3106 - 3113. [Abstract] [Full Text] [PDF]
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P. G. Heller, A. C. Glembotsky, M. J. Gandhi, C. L. Cummings, C. J. Pirola, R. F. Marta, L. I. Kornblihtt, J. G. Drachman, and F. C. Molinas Low Mpl receptor expression in a pedigree with familial platelet disorder with predisposition to acute myelogenous leukemia and a novel AML1 mutation Blood, June 15, 2005; 105(12): 4664 - 4670. [Abstract] [Full Text] [PDF]
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Y. Fukushima-Nakase, Y. Naoe, I. Taniuchi, H. Hosoi, T. Sugimoto, and T. Okuda Shared and distinct roles mediated through C-terminal subdomains of acute myeloid leukemia/Runt-related transcription factor molecules in murine development Blood, June 1, 2005; 105(11): 4298 - 4307. [Abstract] [Full Text] [PDF]
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 D. P. Steensma and A. F. List Genetic Testing in the Myelodysplastic Syndromes: Molecular Insights Into Hematologic Diversity Mayo Clin. Proc., May 1, 2005; 80(5): 681 - 698. [Abstract] [PDF]
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L. A. Nguyen, P. P. Pandolfi, Y. Aikawa, Y. Tagata, M. Ohki, and I. Kitabayashi Physical and functional link of the leukemia-associated factors AML1 and PML Blood, January 1, 2005; 105(1): 292 - 300. [Abstract] [Full Text] [PDF]
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S. Goyama, Y. Yamaguchi, Y. Imai, M. Kawazu, M. Nakagawa, T. Asai, K. Kumano, K. Mitani, S. Ogawa, S. Chiba, et al. The transcriptionally active form of AML1 is required for hematopoietic rescue of the AML1-deficient embryonic para-aortic splanchnopleural (P-Sp) region Blood, December 1, 2004; 104(12): 3558 - 3564. [Abstract] [Full Text] [PDF]
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W. Sun and J. R. Downing Haploinsufficiency of AML1 results in a decrease in the number of LTR-HSCs while simultaneously inducing an increase in more mature progenitors Blood, December 1, 2004; 104(12): 3565 - 3572. [Abstract] [Full Text] [PDF]
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D. H. Christiansen, M. K. Andersen, and J. Pedersen-Bjergaard Mutations of AML1 are common in therapy-related myelodysplasia following therapy with alkylating agents and are significantly associated with deletion or loss of chromosome arm 7q and with subsequent leukemic transformation Blood, September 1, 2004; 104(5): 1474 - 1481. [Abstract] [Full Text] [PDF]
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H. Harada, Y. Harada, H. Niimi, T. Kyo, A. Kimura, and T. Inaba High incidence of somatic mutations in the AML1/RUNX1 gene in myelodysplastic syndrome and low blast percentage myeloid leukemia with myelodysplasia Blood, March 15, 2004; 103(6): 2316 - 2324. [Abstract] [Full Text] [PDF]
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 Y. Imai, M. Kurokawa, Y. Yamaguchi, K. Izutsu, E. Nitta, K. Mitani, M. Satake, T. Noda, Y. Ito, and H. Hirai The Corepressor mSin3A Regulates Phosphorylation-Induced Activation, Intranuclear Location, and Stability of AML1 Mol. Cell. Biol., February 1, 2004; 24(3): 1033 - 1043. [Abstract] [Full Text] [PDF]
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M. Nishimura, Y. Fukushima-Nakase, Y. Fujita, M. Nakao, S. Toda, N. Kitamura, T. Abe, and T. Okuda VWRPY motif-dependent and -independent roles of AML1/Runx1 transcription factor in murine hematopoietic development Blood, January 15, 2004; 103(2): 562 - 570. [Abstract] [Full Text] [PDF]
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Z. Li, J. Yan, C. J. Matheny, T. Corpora, J. Bravo, A. J. Warren, J. H. Bushweller, and N. A. Speck Energetic Contribution of Residues in the Runx1 Runt Domain to DNA Binding J. Biol. Chem., August 29, 2003; 278(35): 33088 - 33096. [Abstract] [Full Text] [PDF]
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 H. Hirai Molecular Mechanisms of Myelodysplastic Syndrome Jpn. J. Clin. Oncol., April 1, 2003; 33(4): 153 - 160. [Abstract] [Full Text] [PDF]
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 M. L. Kalev-Zylinska, J. A. Horsfield, M. V. C. Flores, J. H. Postlethwait, M. R. Vitas, A. M. Baas, P. S. Crosier, and K. E. Crosier Runx1 is required for zebrafish blood and vessel development and expression of a human RUNX1-CBF2T1 transgene advances a model for studies of leukemogenesis Development, March 6, 2003; 129(8): 2015 - 2030. [Abstract] [Full Text] [PDF]
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H. Harada, Y. Harada, H. Tanaka, A. Kimura, and T. Inaba Implications of somatic mutations in the AML1 gene in radiation-associated and therapy-related myelodysplastic syndrome/acute myeloid leukemia Blood, January 15, 2003; 101(2): 673 - 680. [Abstract] [Full Text] [PDF]
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H. Leroy, C. Roumier, N. Grardel-Duflos, E. Macintyre, P. Lepelley, P. Fenaux, and C. Preudhomme Unlike AML1, CBFbeta gene is not deregulated by point mutations in acute myeloid leukemia and in myelodysplastic syndromes Blood, May 15, 2002; 99(10): 3848 - 3850. [Abstract] [Full Text] [PDF]
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J. Michaud, F. Wu, M. Osato, G. M. Cottles, M. Yanagida, N. Asou, K. Shigesada, Y. Ito, K. F. Benson, W. H. Raskind, et al. In vitro analyses of known and novel RUNX1/AML1 mutations in dominant familial platelet disorder with predisposition to acute myelogenous leukemia: implications for mechanisms of pathogenesis Blood, February 15, 2002; 99(4): 1364 - 1372. [Abstract] [Full Text] [PDF]
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A. Buijs, P. Poddighe, R. van Wijk, W. van Solinge, E. Borst, L. Verdonck, A. Hagenbeek, P. Pearson, and H. Lokhorst A novel CBFA2 single-nucleotide mutation in familial platelet disorder with propensity to develop myeloid malignancies Blood, November 1, 2001; 98(9): 2856 - 2858. [Abstract] [Full Text] [PDF]
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Abstract
Introduction
