Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0023467 (acute myeloid leukemia)
 35,200 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Bone marrow specimens obtained from 54 patients with de novo AML and 7 patients with AML evolving from MDS were retrospectively examined for the presence of micromegakaryocytes defined as cells of less than 30 microns in diameter with one or two nuclei. At least 25 megakaryocytes were counted in each patient. Micromegakaryocytes were found in 17 cases (31%), M1:1/11, M2:5/18, M3:0/4, M4:5/12, M5:1/4, M6:4/4, M7:1/1. The median age of the patients was higher in de novo AML with micromegakaryocytes (57 years) than in de novo AML without micromegakaryocytes (41 years) (p = 0.014). Chromosomal analysis revealed that deletion of 5 or 5q-, 7 or 7q- was recognized only in the group of de novo AML with micromegakaryocytes and that t(15;17), t(8:21) and inv (16) were not recognized in this group. Micromegakaryocytes were identified in each bone marrow specimen obtained from 9 of 10 patients with de novo AML with trilineage myelodysplasia. The complete remission rate was significantly lower in de novo AML with micromegakaryocytes (33%) than in de novo AML without micromegakaryocytes (86%) (p = 0.001). The duration of survival of the patients with de novo AML with micromegakaryocytes was shown to be shorter than that of the patients with de novo AML without micromegakaryocytes (p = 0.017). Micromegakaryocytes were recognized in all of 7 patients with AML evolving from MDS. The presence of micromegakaryocytes in bone marrow of the patients with AML indicates a subset of AML with poor prognosis that may be closely associated with myelodysplastic syndrome.
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PMID:[Clinical significance of micromegakaryocytes in de novo AML]. 847 83

A nonrandom translocation between chromosomes 3 and 21, t(3;21)(q26.2;q22) has been detected in patients with a myelodysplastic syndrome or acute myeloid leukemia after treatment (t-MDS/t-AML) for a primary malignant disease and in chronic myelogenous leukemia in blast crisis (CML-BC). In these patients, the breakpoint on chromosome 21 is at band 21q22. This band is also involved in the t(8;21)(q22;q22) detected in 40% of the patients with acute myeloid leukemia subtype M2 (AML-M2) de novo who have an abnormal karyotype. In the t(8;21), the AML1 gene is the site of the breakpoint on chromosome 21. The AML1 gene is transcribed from telomere to centromere, and in the t(8;21) the 5' part of AML1 is fused to the ETO gene on chromosome 8 to produce the chimeric AML1/ETO on the der(8) chromosome. We found that AML1 is also rearranged in two t-AML patients and in one CML-BC patient with the t(3;21), but the breakpoints are approximately 40 to 60 kb downstream to those of AML-M2 patients. This region contains at least one additional exon of AML1, as determined by using an AML1 cDNA as a probe in Southern blot analysis. The t(3;21) breakpoints for the remaining patients could not be determined because, by fluorescence in situ hybridization analysis, the breaks are outside of the region covered by the available probes.
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PMID:Involvement of the AML1 gene in the t(3;21) in therapy-related leukemia and in chronic myeloid leukemia in blast crisis. 849 Jan 81

Most studies of the clonal origin of the underlying lesion(s) and all investigations using X-inactivation, have concluded that the myelodysplastic syndromes arise from a multipotent stem cell. Non-random chromosomal abnormalities, particularly deletions of 5q and 7q, are common, most notably in therapy related MDS. Progression to AML is also frequently accompanied by increased genomic instability as evidenced by the emergence of multiple karyotypic abnormalities. While some evidence hints at the presence of tumour suppressor genes on chromosomes 5, 7, 20 and 12, no such genes have yet been identified. The search for point mutations in known oncogenes has concentrated on two oncogenes RAS and c-FMS. Point mutation frequency generating active forms of RAS oncogenes is approximately 40% in MDS overall, up to 80% in studies of CMML. 60% of all MDS RAS mutation involves a G to A transition, producing a substitution of aspartate for glycine at a frequency of 50% (of total ras mutants). RAS mutation is associated with progression to AML, although the presence of a RAS point mutation alone is neither necessary nor sufficient for leukaemic transformation. Mutation of c-FMS is also more common in CMML in comparison to other MDS subtypes and, as yet, point mutation potentiating the response of the receptor to CSF-1 (codon 969) has been found more frequently than point mutation resulting in permanently activated receptor (codon 301). However, recent work has identified additional mutations which produce transforming proteins, and mutation rates at these sites may be relevant in MDS.
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PMID:Myelodysplastic syndromes: from morphology to molecular biology. Part II. The molecular genetics of myelodysplasia. 849 99

Finding a clone in the bone marrow of a patient with a hematologic disorder is important to confirm the neoplastic nature of the disease and may be indicative of prognosis. Since cytogenetic analysis detects only actively dividing clones, the presence of a single abnormal cell among 20 cells analyzed raises doubts about its clonal nature. Fluorescence in situ hybridization (FISH) enables rapid detection of certain chromosomal abnormalities in metaphase and interphase cells, thus enabling detection of minor or inactive clones. Seven patients with hematologic malignancy each having random cell(s) were investigated thus: at diagnosis, with MDS and a cell with +8 (two cases) or +9 (one case) and with AML and a cell with +4 (one case), +7 (one case), or two cells with +9, +22/ +10, +17, +17 (one case). One patient with ALL in remission had one cell with trisomy 4. One patient, a male aged 66 years with refractory anemia with ringed sideroblasts, was found to have a minor trisomy 8 clone in his diagnostic marrow. A follow-up marrow 42 months later showed no trisomy 8 cell among 62 metaphases analyzed, and the percentage of trisomic cells using FISH on interphase cells was within the control range. This patient has survived for more than 42 months requiring no treatment. Single-cell abnormalities in the other six cases proved to be random events. Thus it appears that single-cell abnormalities may not be clonal or at most indicate the presence of a minor clone well below the level of cytogenetic detection. The prognostic significance of such minor clones is at present unclear.
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PMID:Single-cell trisomy in hematologic malignancy. Random change or tip of the iceberg? 878 Jul 56

As a first step to evaluate the possibility of gene therapy using adenoviral vectors in hematological malignancies in vivo, we tested the efficacy of gene transfer by a recombinant adenovirus in cell lines and fresh cells from various hematological neoplasms. Thirteen cell lines and samples from 27 patients were studied. Cells were infected by a recombinant adenovirus expressing beta galactosidase gene (Ad RSV betagal) and efficacy of transduction assessed by evaluating betagal expression in cells with a histochemical method. After infection of the cells at a multiplicity of infection (MOI) of 200 p.f.u./cell, the percentage of beta gal-positive cells after 48h was high in two cell lines. K562 (64%) and RPMI 8226 (a myeloma cell line, 65%), relatively large in the two myeloma cell lines tested (41% and 20%, respectively) and in MT4 (an adult T cell leukemia cell line, 38%) and low or absent in other cell lines. In fresh samples from AML, ALL, CLL, NHL, myeloma and MDS, no betagal positive cells were seen 48h and 72h after infection, except in one case of myeloma and one case of CLL (where 10% and 2% of betagal positive cells were seen after infection, respectively). Exposure of fresh malignant cells to GM-CSF before and during adenoviral infection, in three cases, did not increase the number of transfected cells. This suggests that adenoviral vectors, at least in their present form, cannot efficiently be used for direct gene transfer in hematological malignant cells.
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PMID:Differential efficacy of adenoviral mediated gene transfer into cells from hematological cell lines and fresh hematological malignancies. 855 24

Platelet function was studied in a child with myelodysplastic syndrome (MDS: refractory anemia with an excess of blasts) and a child with acute myeloblastic leukemia (AML-M6) associated with trilineage myelodysplasia (TMDS). An acquired Bernard-Soulier-like platelet defect was considered in both patients with the findings of prolonged bleeding time and abnormally large platelets that failed to aggregate in response to ristocetin. In contrast to findings in von Willebrand's disease, the abnormal response of platelets to ristocetin could not be corrected by the addition of normal flesh plasma. The detection of abnormal platelet aggregation response to ristocetin may be a useful diagnostic finding for clonal disorders causing impaired platelet function in MDS and coexistent TMDS associated with AML. Further studies of ristocetin-induced platelet aggregation in a large number of these patients are required.
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PMID:Bernard-Soulier-like functional platelet defect in myelodysplastic syndrome and in acute myeloblastic leukemia associated with trilineage myelodysplasia. 856 Jun 14

Although molecular and cytogenetic studies strongly point to the role of oncogenes, the mechanisms underlying the development of MDS and their progressive evolution to AML are still largely unknown. It has been postulated that AML has a preleukemic stage and a multi step pathogenesis, with the preleukemic stem cell able to undergo clonal evolution, with the acquisition of karyotypic abnormalities, leading to the development of acute leukemic subclones. The activations of the ras oncogenes or inactivation of the p53 anti-oncogene by point mutations have been described recently in several cases of MDS as well as AML, suggesting a critical role for these alterations in the development of these myelogenous leukemias. We reported previously establishment of a leukemic cell line, SKM-1, from the patient who initially possessed multiple point mutations of ras genes but lost these mutations during disease progression to myelomonocytic leukemia with acquisition of chromosomal abnormalities involving the p53 anti-oncogene. This process is characterized by genetic instabilities probably due to the failure of their DNA repairment leading to abnormal control of cell proliferation and differentiation. Studying this cell line, SKM-1, is a promising approach to understand the mechanisms of the initiation, disease progression, alterations of DNA repairment, and genetic instability in MDS and myelogenous malignancies.
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PMID:The SKM-1 leukemic cell line established from a patient with progression to myelomonocytic leukemia in myelodysplastic syndrome (MDS)-contribution to better understanding of MDS. 858 Aug 5

A previously healthy 74-year-old patient without a prior history of hematological disease presented with an acute respiratory infection. Peripheral pancytopenia led us to perform a bone marrow biopsy, and the diagnosis of undifferentiated acute myelogenous leukemia (AML, 61% blasts) was made. Following antibiotic treatment and resolution of the infection, the blast count in the bone marrow fell to 2%, leaving a clinicopathologic picture consistent with myelodysplastic syndrome (MDS, French-American-British type refractory anemia), and the patient survived for a total of 16.5 months following the initial presentation with cytokine support. A preterminal blast proliferation occurred during a bacterial ear infection and rapidly responded to a withdrawal of cytokine support, antibiotic therapy, and hydroxyurea. The patient succumbed ultimately to an apparent myocardial infarct. Clinicians should consider transient acceleration of MDS in their differential diagnosis when confronted with apparent AML and acute infection.
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PMID:Recent-onset myelodysplastic syndrome mimicking acute leukemia during infection. 859 13

The aim of the present study was to increase our knowledge of myelopoiesis evaluated by flow cytometry. We therefore designed a triple-marker assay employing monoclonal antibodies against the CD13 (immature), the CD14 (monocytic), and the CD66 (mature myeloid) antigens using three-colour immunofluorescence. In normal donor bone marrow the assay enables simultaneous identification of immature (CD13+, CD14-, CD66-), intermediate (CD13+, myelopoietic differentiation stages through the exclusion of CD14+ monocytic cells. In the diagnosis and longitudinal follow-up of AML patients the assay was of value in the fast determination of remission state. In MDS, the immature myeloid component could be distinguished in patients defined according to the FAB classification with the possibility of identifying aberrant phenotypes, the assay should also be of interest in other myeloproliferative disorders. Moreover, because it is easy to perform, time-saving, and yields comparable results to single antibody reactivity controls, it can replace more tedious and less-informative flow cytometric immunophenotyping procedures.
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PMID:Improved flow cytometric identification of myelopoiesis by the simultaneous labelling with CD13, CD14 and CD66 monoclonal antibodies. 860 85

A 48-year-old Japanese man was admitted to our hospital because of general fatigue, nasal bleeding, and petechiae on his extremities. He was diagnosed with acute myelomonocytic leukemia with trilineage myelodysplasia (T-MDS). Chromosomal analysis of bone marrow cells revealed t(7;11)(p15;p15), which has been rarely reported but known to be characteristic of Japanese patients. Although t(7;11)(p15;p15) has been reported mainly in acute myelogenous leukemia (AML), it can be occasionally found in so-called stem cell diseases such as chronic myelogenous leukemia or chronic myeloproliferative disorders. Therefore, t(7;11)(p15;p15) might affect trilineage progenitors or stem cells as well as myeloid lineage cells, subsequently resulting in AML with T-MDS, as in our case reported here.
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PMID:t(7;11) and trilineage myelodysplasia in acute myelomonocytic leukemia. 861 92


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