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)

Until now, reports on the cell cycle distribution of AML patients have shown highly variable results which are probably related to the technical heterogeneity of such studies. The aim of the present paper was to analyse in 204 AML patients at diagnosis the proliferative rate (assessed by the number of S-phase cells) of peripheral blood (PB) (126 cases) and bone marrow (BM) (78 cases) cells in order to explore its relationship with disease characteristics. A strong parallelism was observed regarding the relationship between the proliferative rate of the blast cells both in PB and in BM and the disease characteristics. Cases with a high proliferative rate were associated with advanced age, high WBC counts and LDH serum levels, monocytic leukaemias (assessed both by morphological and immunophenotypic criteria) and NK-associated antigens (CD56, CD16). The proliferative activity did not influence the CR rate; in contrast, cases with a high number of S-phase cells had shorter survival. In addition, multivariate analysis showed that age, the expression of CD11b, and the S-phase counts are the only three prognostic factors displaying an independent impact on survival.
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PMID:Prognostic value of S-phase cells in AML patients. 787 84

To date no hematopoietic progenitors of dendritic Langerhans' cells (DLC), which represent an highly efficient class of antigen presenting cells, have been identified or the cytokines they elaborate have been defined. Here we describe an acute leukemia patient whose blasts (90-96% in peripheral blood and bone marrow) had a phenotype consistent with putative progenitors of DLC. The patient was treated with ara-C and VP-16 but did not achieve remission. The blasts had lobulated nuclei, no cytoplasmic vacuolation or Auer rods and were weakly positive for acid phosphatase and non-specific esterase and negative for PAS, granzyme A, dipeptidyl aminopeptidase IV, ATPase/ADPase and lysozyme production. The blasts were positive for CD1a, CD4, CD16, CD35, HLADR, HLADQ, CD11b, CD11c, CD14, CD33, CD34, CD11a, CD71, CD19, CD25, IL-2R beta and negative for CD2, CD7, CD8, CD10, CD22, CD56, CD57, surface or cytoplasmic CD3, TCR delta and TCR beta, HTLV-1p19 and P-glycoprotein. On liquid culture with or without 5 x 10(-9) M 12-O-tetradecanoylphorbol-13-acetate (TPA) for 3 days, the blasts formed aggregates of proliferating and elongating cells on the wall of the flasks with a decline in CD34, numerous dendritic processes appeared on the cells and there was strong positivity for ATPase/ADPase, but no other changes in phenotype. No macrophages were observed, indicating derivation from separate DLCs. Cytogenetic analysis showed chromosomal abnormalities and electron microscopy showed Birbeck granules. Southern blotting of DNA showed rearrangement of one allele for both JH and TCR beta but no HTLV-1 related sequences. Culture supernatants from blasts cultured with or without TPA showed the production of large amounts of IL-8, IL-6, TNF-alpha, MIP-1 alpha, IL-10 and interferon gamma and modest amounts of IL-1 alpha, GM-CSF and stem cell factor. The presence not only of CD1a, HLADR, HLADQ and many other characteristics including Birbeck granules, but also differentiation along the lines of DLC with appearance of dendritic processes on the cells and expression of ATPase/ADPase activity, indicate that the leukemic blasts in our patient represented a leukemic counterpart of normal progenitors of DLC and the leukemia a new entity which could possibly be classified as AML-M8. Lastly, many pro-inflammatory cytokines produced by DLC could contribute to inflammation and IL-10 to immunosuppression.
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PMID:Phenotype, genotype and cytokine production in acute leukemia involving progenitors of dendritic Langerhans' cells. 791 55

The multidrug resistance-associated protein (MRP) gene is a member of the ATP-binding cassette transporter gene superfamily and may be partially responsible for clinical drug resistance. Reverse transcriptase-polymerase chain reaction was used to measure MRP mRNA in normal hematopoietic cells from bone marrow and peripheral blood as well as patients with high risk acute myelocytic leukemia and multiple myeloma. All normal peripheral blood cells, regardless of cell lineage (CD4, CD8, CD14, CD15, CD19, CD56), expressed a similar basal level of MRP mRNA. Specimens from bone marrow containing mixed lineages also expressed a similar basal level of MRP expression. In patients with acute myelocytic leukemia, 10 of 12 (83%) of the specimens had detectable MRP mRNA, but the level of expression was similar to that of normal blood cells and low compared to a cell line known to overexpress MRP (H69/AR). All myeloma patients (12 of 12) had detectable MRP mRNA expression at levels comparable to normal peripheral blood and bone marrow cells. We conclude that MRP is commonly expressed in normal hematopoietic cells as well as certain hematopoietic malignancies. The therapeutic relevance of MRP expression is unknown, but these studies emphasize the importance of measuring MRP expression in normal cells as a point of reference and comparison for detection in malignant cells. We also recommend obtaining sequential specimens from patients, which may reveal an increased expression of MRP from baseline as the disease progresses and becomes resistant.
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PMID:Analysis of multidrug resistance-associated protein (MRP) messenger RNA in normal and malignant hematopoietic cells. 806 63

Transplantation of bone marrow autografts activated by culture in interleukin-2 (IL-2) followed by administration of IL-2 represents a novel approach in an attempt to combine ex vivo purging and post-transplant in vivo immunotherapy, and initial clinical results have suggested its feasibility. To further characterize the mechanism of the in vitro anti-leukemia effect, fresh bone marrow from normal donors and from patients with acute myelogenous leukemia (AML) in remission was cultured for 6 days in the absence or presence of IL-2 (1000 IU/ml). Proliferation of CD3, CD8, CD14, and CD56 cells was determined by direct immunofluorescence using flow cytometry. Predominantly T-lymphocytes (CD3+) and to a lesser extent CD56+ natural killer (NK) cells proliferate in 6-day marrow cultures in IL-2. Fresh bone marrow cells have no measurable NK activity when tested against K562 and Daudi target cell lines in a 4 h chromium-51 release assay, and it requires at least 6 days of culture in IL-2 to develop optimal cytotoxic activity. Cytokines released in the supernatants of these cultures were measured by immuno- and bioassays. Tumour necrosis factor alpha (TNF-alpha), interferon gamma (IFN-gamma), and IL-6 were found to be produced in significant amounts by marrow mononuclear cells during culture in IL-2. Even without IL-2 present, concentrations of these cytokines were increased in 6-day marrow cultures. In contrast, IL-3, IL-7, granulocyte and granulocyte-macrophage colony-stimulating factors (G-CSF and GM-CSF) were below the level of detection of the immunoassay, a result that could be confirmed for GM-CSF and IL-3 by bioassay. The data suggest that culture of marrow from normal donors as well as from patients with AML obtained in remission can generate anti-leukemia effector mechanisms which are non-crossreactive with chemo- and radiotherapy and may contribute to effective ex vivo purging of residual leukemic cells. The transplantation of such IL-2 'primed' marrow may also contribute to an in vivo graft-versus-leukemia effect.
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PMID:Culture of normal and leukemic bone marrow in interleukin-2: analysis of cell activation, cell proliferation, and cytokine production. 837 89

During the immunodiagnosis of 517 cases of acute myelogenous leukemia (AML) entered into the Medical Research Council (MRC) AML 10 trials, we have observed the CD34 precursor cell antigen more frequently in AML of M2 morphology, especially in the 84% of cases with the t(8;21) chromosomal translocation, than in any other French-American-British classification group. CD34 expression was then quantified (using QIFI and Quantum Simply Cellular beads [Flow Cytometry Standards, Research Triangle Park, NC] and CD34+ standard cells). When CD34 antibody-binding capacity (ABC) of normal bone marrow (BM) precursors and leukemic blasts was compared, it was shown that AML M2 cases with t(8;21) not only had the highest percentages of CD34+ blasts, but in > 80% of CD34+ cases the individual blasts expressed higher than normal levels of CD34 antigen (> 60 x 10(3) ABC per cell). In addition, in 73% of this group CD34 antigen was overexpressed in an asynchronous combination with cytoplasmic myeloperoxidase (MPO). Other signs of asynchrony included high CD34 expression with CD15 and/or CD56, as well as aberrant combinations of CD13 with terminal deoxynucleotidyl transferase (TdT) and CD19. These findings demonstrate that asynchrony is identifiable in virtually every case of AML with t(8;21), although it does not always involve the same antigens. M2 cases with t(8;21), mostly CD34+, had a 100% remission rate and 71% 5-year survival rate; other patients with CD34+ or CD34- AML showed 69% and 84% remission rates and 31% and 36% 5-year survival rates, respectively. Consequently, individual markers such as CD34 should be interpreted in relation to other features such as chromosomal changes. These simple methods, which are well suited to quantify the expression of ligands, are a useful contribution to diagnosis: 60% to 65% of M2 cases with t(8;21) are rapidly identified by CD34 overexpression alone. This aberration, together with the other signs of asynchrony seen at presentation, can be used to search for residual leukemia after therapy.
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PMID:Leukemia-associated changes identified by quantitative flow cytometry. IV. CD34 overexpression in acute myelogenous leukemia M2 with t(8;21). 856 43

Here we report a case of acute myelogenous leukemia (M2, FAB classification) presenting with cytogenetic abnormalities of ins(21;8), +del(8) without t(8;21). A 8;21 chromosome translocation is frequently found in acute myelogenous leukemia, especially in the M2 subtype. The translocation results in a fusion transcript between AML1 and MTG8 (ETO), assigned on chromosomes 21 and 8, respectively. Among patients with a t(8;21) abnormality, solid leukemic tumor deposits outside the marrow or good response to chemotherapy are observed frequently. Decrease in neutrophil alkaline phosphatase score and positive rate, and eosinophilia in bone marrow or the blast cells with Auer rods expressing CD19, CD56 antigens occur at a relatively high rate. Although our case lacked these clinical, cytological and cytochemical features, expression of chimeric AML1-MTG8 mRNA was detected. AML1-MTG8 fusion transcript may play a critical role in leukemogenesis of AML M2. Studies on this case may help to reveal the oncogenic function of the AML1-MTG8 fusion gene in AML M2.
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PMID:[Acute myelogenous leukemia with ins(21;8) expressing AML-1-MTG8 fusion transcript]. 896 Jun 65

The CD56 antigen is normally expressed on natural-killer cells but has additionally been shown to be present on a variety of hematologic malignancies, including a subset of acute myelogenous leukemia (AML). There is disagreement, however, about its prognostic significance and its association with specific cytogenetic abnormalities. All clinical samples from June 1994, through September 1995, with increased myeloblasts were analyzed by multiparameter flow cytometry for anomalous expression of CD56. Patients with CD56+ blast cells were selected, and morphologic review was performed. Clinical information was obtained, and cytogenetic data were reviewed. Southern blot analysis to detect rearrangement of the mixed lineage leukemia (MLL) gene was performed when possible. The samples from 23 of 114 patients studied demonstrated anomalous expression of CD56 on myeloblasts, including patients with AML, myelodysplastic syndromes (MDS), and chronic myelogenous leukemia in blast crisis. The samples from 10 of 15 patients with CD56+ AML demonstrated at least partial monocytic differentiation. Dysplastic features were displayed in the samples of 12 patients. Correlation with specific cytogenetic abnormalities was not found. The MLL gene was rearranged in five of 18 patients. Seventeen patients have died, with a median survival of 4.6 months for patients with AML. Three have sustained a complete remission. One has findings of high-grade myelodysplastic syndrome. Two were unavailable for follow-up. Expression of CD56 was found in 20% of patients with increased myeloblasts, including patients with high-grade MDS, chronic myelogenous leukemia in blast crisis, and AML. This phenotype was associated with dysplasia, monocytic differentiation, and rearrangement of the MLL gene.
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PMID:Neural cell adhesion molecule (CD56)-positive acute myelogenous leukemia and myelodysplastic and myeloproliferative syndromes. 916 61

Expression of the multidrug resistance (MDR) phenotype is an independent prognostic variable in acute myeloid leukemia. Approximately 43-57% of the patients have P-glycoprotein (P-gp) expression. A major drawback with the interpretation of P-gp data in AML is the lack of coherence with different analytical assays. We have focused our efforts of P-gp detection on flow cytometry using a dual technique of P-gp staining with antibodies for the extracellular epitope (MRK16) and a functional analysis of P-gp using the rhodamine efflux assay and the effect of P-gp inhibitors such as SDZ PSC 833. This technique was combined with the staining of lineage-specific antigens such as CD34, CD56 and c-kit. In this way, various subsets of AML cells can be identified such as MRK 16+/-, CD34+/- blasts. These cells can be sorted for further analysis, such as the molecular expression of P-gp and other pleiotropic drug resistance genes.
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PMID:Assays for the analysis of P-glycoprotein in acute myeloid leukemia and CD34 subsets of AML blasts. 920 6

Although acute myeloid leukemia (AML) with t(8;21) (q22;q22) is associated with a high complete remission (CR) rate and prolonged disease-free survival, treatment outcome is not universally favorable. Identifying factors that predict for treatment outcome might allow therapy to be optimized based on risk. AML with t(8;21) has a distinctive immunophenotype, characterized by expression of the myeloid and stem cell antigens CD13, CD15, CD34, and HLADr, and frequent expression of the B-cell antigen CD19 and the neural cell adhesion molecule CD56, a natural killer cell/stem cell antigen. Because CD56 expression has been associated with both extramedullary leukemia and multidrug resistance, we sought to correlate CD56 expression with treatment outcome in AML with t(8;21). Pretreatment leukemia cells from 29 adult de novo AML patients with t(8;21) treated on Cancer and Leukemia Group B (CALGB) protocols were immunophenotyped by multiparameter flow cytometry as part of a prospective immunophenotyping study of adult AML (CALGB 8361). CD56 was expressed in 16 cases (55%). There was no correlation between CD56 expression and age, sex, white blood cell count, granulocyte count, the presence of additional cytogenetic abnormalities, or the presence of extramedullary disease at diagnosis. The CR rate to standard-dose cytarabine and daunorubicin was similar for cases with and without CD56 expression (88% v 92%; P = 1.0). Post-CR therapy included at least one course of high-dose cytarabine in 24 of 26 patients who achieved CR; numbers of courses administered were similar in cases with and without CD56 expression. Although post-CR therapy did not differ, CR duration was significantly shorter in cases with CD56 expression compared with those without (median, 8.7 months v not reached; P = .01), as was survival (median, 16.5 months v not reached; P = .008). We conclude that CD56 expression in AML with t(8;21) is associated with significantly shorter CR duration and survival. Our results suggest that CD56 expression may be useful in stratifying therapy for this subtype of AML.
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PMID:Expression of the neural cell adhesion molecule CD56 is associated with short remission duration and survival in acute myeloid leukemia with t(8;21)(q22;q22). 926 84

The disease spectrum of natural killer (NK) cell leukemias and lymphomas has recently been expanding with the continuing evolution in diagnostic concepts. We describe here seven cases of acute leukemia of conceivable myeloid and NK cell precursor phenotype in six men and one woman varying from 19 to 59 years of age (median, 46 years). Striking extramedullary involvement was evident at initial presentation, with peripheral lymphadenopathy and/or mediastinal masses. Two lacked any leukemic cells in the bone marrow at diagnosis. Using cytochemical myeloperoxidase staining, less than 3% of the leukemic cells showed positive reactivity. However, expression of CD7, CD33, CD34, CD56, and frequently HLA-DR, but not other NK, T-cell, and B-cell markers was observed. Cytoplasmic CD3 was detected in three of the cases by flow cytometry and in six by Northern blotting, suggesting an origin from common progenitors between the NK cell and myeloid lineages. All but one presented germline configurations of the T-cell receptor beta and gamma chain genes and Ig heavy chain gene. With regard to morphology, the cells were generally L2-shaped, with variation in cell size, round to moderately irregular nuclei and prominent nucleoli, pale cytoplasm, and a lack of azurophilic granules. Histopathologic examination of biopsied specimens of extramedullary tumors showed a lymphoblast-like morphology, implying the differential diagnostic problem from lymphoblastic lymphomas, especially in cases lacking bone marrow involvement. Three patients were successfully treated with chemotherapy for acute myeloid leukemia (AML), whereas three other patients proved refractory to chemotherapeutic regimens for lymphoid malignancies, although two responded to subsequent AML chemotherapy. However, despite intensive chemotherapy, including allogeneic bone marrow transplantation, most persued fatal courses within 41 months. These data suggested that the CD7+ and CD56+ myeloid/NK cell precursor acute leukemia might constitute a distinct biologic and clinical disease entity. Its recognition appears to be particularly important for the clinicopathologic evaluation of CD56+ hematolymphoid malignancies and the development of therapeutic approaches to such disease.
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PMID:CD7+ and CD56+ myeloid/natural killer cell precursor acute leukemia: a distinct hematolymphoid disease entity. 931 Apr 93


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