High incidence of biallelic point mutations in the Runt domain of the AML1/PEBP2 alpha B gene in Mo acute myeloid leukemia and in myeloid malignancies with acquired trisomy 21.

The AML1 gene, situated in 21q22, is often rearranged in acute leukemias through t(8;21) translocation, t(12;21) translocation, or less often t(3;21) translocation. Recently, point mutations in the Runt domain of the AML1 gene have also been reported in leukemia patients. Observations for mutations of the Runt domain of the AML1 gene in bone marrow cells were made in 300 patients, including 131 with acute myeloid leukemia (AML), 94 with myelodysplastic syndrome (MDS), 28 with blast crisis chronic myeloid leukemia (CML), 3 with atypical CML, 41 with acute lymphoblastic leukemia (ALL), and 3 with essential thrombocythemia (ET). Forty-one of the patients had chromosome 21 abnormalities, including t(8;21) in 6 of the patients with AML, t(12;21) in 8 patients with ALL, acquired trisomy 21 in 17 patients, tetrasomy 21 in 7 patients, and constitutional trisomy 21 (Down syndrome) in 3 patients. A point mutation was found in 14 cases (4.7%), including 9 (22%) of the 41 patients with AML of the Mo type (MoAML) (none of them had detectable chromosome 21 rearrangement) and 5 (38%) of the 13 myeloid malignancies with acquired trisomy 21 (1 M1AML, 2 M2AML, 1 ET, and 1 atypical CML). In at least 8 of 9 mutated cases of MoAML, both AML alleles were mutated: 3 patients had different stop codon mutations of the 2 AML1 alleles, and 5 patients had the same missense or stop codon mutation in both AML1 alleles, which resulted in at least 3 of the patients having duplication of the mutated allele and deletion of the normal residual allele, as shown by FISH analysis and by comparing microsatellite analyses of several chromosome 21 markers on diagnosis and remission samples. In the remaining mutated cases, with acquired trisomy 21, a missense mutation of AML1, which involved 2 of the 3 copies of the AML1 gene, was found. Four of the 7 mutated cases could be reanalyzed in complete remission, and no AML1 mutation was found, showing that mutations were acquired in the leukemic clone. In conclusion, these findings confirm the possibility of mutations of the Runt domain of the AML1 gene in leukemias, mainly in MoAML and in myeloid malignancies with acquired trisomy 21. AML1 mutations, in MoAML, involved both alleles and probably lead to nonfunctional AML1 protein. As AML1 protein regulates the expression of the myeloperoxidase gene, the relationship between AML1 mutations and Mo phenotype in AML will have to be further explored. (Blood. 2000;96:2862-2869)

[1]  B. Chait,et al.  Immunoglobulin motif DNA recognition and heterodimerization of the PEBP2/CBF Runt domain , 2000, Nature Structural Biology.

[2]  M. H. Werner,et al.  Runt domains take the lead in hematopoiesis and osteogenesis , 1999, Nature Medicine.

[3]  John M. Maris,et al.  Haploinsufficiency of CBFA2 causes familial thrombocytopenia with propensity to develop acute myelogenous leukaemia , 1999, Nature Genetics.

[4]  H. Yamasaki,et al.  Biallelic and heterozygous point mutations in the runt domain of the AML1/PEBP2alphaB gene associated with myeloblastic leukemias. , 1999, Blood.

[5]  Francesco Pagano,et al.  Duplication and overexpression of the mutant allele of the MET proto-oncogene in multiple hereditary papillary renal cell tumours , 1998, Oncogene.

[6]  Y. Ito,et al.  Negative regulation of granulocytic differentiation in the myeloid precursor cell line 32Dcl3 by ear-2, a mammalian homolog of Drosophila seven-up, and a chimeric leukemogenic gene, AML1/ETO. , 1998, Proceedings of the National Academy of Sciences of the United States of America.

[7]  M. Giphart-Gassler,et al.  Chromosome loss with concomitant duplication and recombination both contribute most to loss of heterozygosity in vitro , 1998, Genes, chromosomes & cancer.

[8]  J. Kere,et al.  Evidence for two molecular steps in the pathogenesis of myeloid disorders associated with deletion of chromosome 7 long arm , 1997, Leukemia.

[9]  H. Cavé,et al.  ETV6 is the target of chromosome 12p deletions in t(12;21) childhood acute lymphocytic leukemia , 1997, Leukemia.

[10]  M. Owen,et al.  Mutations Involving the Transcription Factor CBFA1 Cause Cleidocranial Dysplasia , 1997, Cell.

[11]  Yoshiaki Ito,et al.  The Runt Domain Transcription Factor, PEBP2/CBF, and its Involvement in Human Leukemia , 1997 .

[12]  Yoshiaki Ito,et al.  Functional Dissection of the α and β Subunits of Transcription Factor PEBP2 and the Redox Susceptibility of Its DNA Binding Activity* , 1996, The Journal of Biological Chemistry.

[13]  R. Bronson,et al.  Absence of fetal liver hematopoiesis in mice deficient in transcriptional coactivator core binding factor beta. , 1996, Proceedings of the National Academy of Sciences of the United States of America.

[14]  J. Rowley,et al.  Synergistic up-regulation of the myeloid-specific promoter for the macrophage colony-stimulating factor receptor by AML1 and the t(8;21) fusion protein may contribute to leukemogenesis. , 1996, Proceedings of the National Academy of Sciences of the United States of America.

[15]  M. Marín‐Padilla,et al.  Disruption of the Cbfa2 gene causes necrosis and hemorrhaging in the central nervous system and blocks definitive hematopoiesis. , 1996, Proceedings of the National Academy of Sciences of the United States of America.

[16]  P. Marynen,et al.  The 12;21 translocation involving TEL and deletion of the other TEL allele: two frequently associated alterations found in childhood acute lymphoblastic leukemia. , 1996, Blood.

[17]  T. Golub,et al.  The t(12;21) translocation converts AML-1B from an activator to a repressor of transcription , 1996, Molecular and cellular biology.

[18]  J. Downing,et al.  AML1, the Target of Multiple Chromosomal Translocations in Human Leukemia, Is Essential for Normal Fetal Liver Hematopoiesis , 1996, Cell.

[19]  J. Rowley,et al.  AML1 and the 8;21 and 3;21 translocations in acute and chronic myeloid leukemia. , 1995, Blood.

[20]  D. Le Paslier,et al.  The t(12;21) of acute lymphoblastic leukemia results in a tel-AML1 gene fusion. , 1995, Blood.

[21]  H. Hirai,et al.  An acute myeloid leukemia gene, AML1, regulates hemopoietic myeloid cell differentiation and transcriptional activation antagonistically by two alternative spliced forms. , 1995, The EMBO journal.

[22]  Y. Ito,et al.  PEBP2/PEA2 represents a family of transcription factors homologous to the products of the Drosophila runt gene and the human AML1 gene. , 1993, Proceedings of the National Academy of Sciences of the United States of America.

[23]  N. Carter,et al.  Analysis of chromosome 21 copy number in uncultured amniocytes by fluorescence in situ hybridization using a cosmid contig , 1992, Prenatal diagnosis.

[24]  H. Gralnick,et al.  Proposal for the recognition of minimally differentiated acute myeloid leukaemia (AML‐MO) , 1991, British journal of haematology.

[25]  T. Sekiya,et al.  Detection of ras gene mutations in human lung cancers by single-strand conformation polymorphism analysis of polymerase chain reaction products. , 1990, Oncogene.

[26]  T. Sekiya,et al.  Rapid and sensitive detection of point mutations and DNA polymorphisms using the polymerase chain reaction. , 1989, Genomics.

[27]  T. P. Dryja,et al.  Expression of recessive alleles by chromosomal mechanisms in retinoblastoma , 1983, Nature.

[28]  Iscn.  International System for Human Cytogenetic Nomenclature , 1978 .