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)

Immunohistochemical investigations were performed on decalcified, paraffin-embedded iliac crest trephine biopsy specimens from 30 cases of acute myeloid leukemia (AML, as defined by the FAB classification) with antibodies against B cells (L26, 4KB5, MB1, Ki-B3), T cells (UCHL1, MT1), myeloid/histiocytic cells (anti-neutrophil elastase, MAC387, anti-S-100 protein, anti-alpha 1-antichymotrypsin, DAKO-M1), natural killer/killer cells (anti-Leu-7), and megakaryocytes (anti-factor VIII-related antigen). (1) The blast cells of all the cases reacted with from at least two to at most eight different antibodies. Each antibody reacted with blast cells in a minimum of two (maximum 30) cases. (2) MT1, Ki-B3, anti-alpha 1-antichymotrypsin anti-neutrophil elastase, anti-S-100 protein, and MAC387 stained blast cells in more than 50% of the cases; MB1, L26, UCHL1, 4KB5, and DAKO-M1 in 20% to 50% of the cases; and anti-Leu-7 and anti-factor VIII-related antigen in less than 20% of the cases. (3) In the majority of cases many T lymphocytes, a small-to-moderate number of B lymphocytes, and a few Leu-7-positive lymphoid cells were intermingled with the blast cells. In some cases, especially where only a minor proportion of the blast cells was immunostained, it was nearly impossible to distinguish the lymphocytes of the tumor's stromal reaction from small blast cells. Thus, AML exhibits a heterogeneous immunophenotype in trephine biopsy specimens. Immunohistologic diagnosis of this disease in such specimens may be extremely difficult. Since staining of the blast cells with one or more of the antibodies generally used to define B cells, T cells, or their neoplastic derivatives is not uncommon, misinterpretation as non-Hodgkin's lymphoma of high-grade malignancy could easily occur. These findings also suggest that mixed-type (hybrid) acute leukemias with coexpression of myeloid and lymphoid cell markers could be more common than generally realized.
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PMID:Acute myeloid leukemia: immunohistologic findings in paraffin-embedded bone marrow biopsy specimens. 169 93

Two cytochemical methods for detection of granulocytic elastase and chymotrypsin employing alanine and phenylalanine naphthyl esters were developed. Specificity of reaction with the ester substrates was proven by chloromethyl ketone inhibitors. The results of both staining methods were almost identical with the staining for naphthol AS-D chloroacetate (Cl Ac-O Nap AS-D) esterase, since Cl Ac-O Nap AS-D also reacts with granulocyte elastase and chymotrypsin. Mature neutrophils and myeloid precursors except myeloblasts are stained with all three substrates in peripheral blood and bone marrow. Mast cells, however, only react with Cl Ac-O Nap AS-D and the chymotrypsin substrate and not with the elastase substrate. In acute myeloid leukemia the three esterases appear in parallel at a somewhat later stage of maturation than myeloperoxidase. In blood smears from 380 hospital patients no hereditary elastase or chymotrypsin deficiency could be demonstrated. Staining for elastase and chymotrypsin was also normal in hereditary myeloperoxidase deficiency and chronic granulomatous disease. On the other hand 6% of the hospital patients and about two-thirds of patients with acute myeloid leukemia showed a partial elastase deficiency in more than 25% of the peripheral neutrophils.
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PMID:Cytochemical determination of granulocyte elastase and chymotrypsin in human myeloid cells and its application in acquired deficiency states and diagnosis of myeloid leukemia. 630 May 11

A systematic morphological analysis of cutaneous infiltrates in acute myelogenous leukemia and myelodysplastic syndrome revealed that in many cases the infiltrating cells have a different phenotype from those in the bone marrow. This study sought to answer two questions: (a) How wide is the range of cytological features and immunoreactivity of the cutaneous infiltrates and what danger is there of misinterpretation? (b) What are the possible causes of the wide spectrum of differentiation of the cells infiltrating the skin? Skin biopsy specimens from 16 patients with myelogenous leukemia or myelodysplastic syndrome were investigated. The diagnosis was acute myelomonocytic leukemia (M4, according to the French-American-British/FAB system of classification of acute leukemias) in eight cases, acute monocytic leukemia (M5) in four cases, aleukemic leukemia cutis as a recurrence of M2 leukemia after treatment in one case, and myelodysplastic syndrome in three cases, including one case of myelodysplasia with an excess of bone marrow blasts (RAEB-T) and two cases of chronic myelomonocytic leukemia, one of which presented as aleukemic leukemia cutis. Reactivity with the macrophage-associated antibodies anti-CD68, Ki-M1p, and anti-lysozyme was the most consistent. However, the naphthol AS-D chloroacetate esterase reaction and staining with DAKO-M1, Ki-My2p, anti-neutrophil elastase, and anti-CD34 were found to be of little value for identifying the cutaneous infiltrate as myelogenous. Some antibodies (e.g., anti-S100 protein and MB2) even produced staining in a few cases that could have led to a mistaken diagnosis of histiocytic neoplasm or malignant lymphoma.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Skin involvement in myelogenous leukemia: morphologic and immunophenotypic heterogeneity of skin infiltrates. 754 88

The value of immunohistochemical staining in the subtyping of acute leukemia was investigated on 36 routinely processed (formalin-fixed and paraffin-embedded) trephine biopsy specimens from the iliac crest containing diffuse infiltrates of acute myelogenous leukemia (AML; n = 23) and acute lymphoblastic leukemia (ALL; n = 13). These were stained with a broad panel of antibodies (n = 23) against various leukocyte antigens, among them 11 macrophage-associated antibodies (MAAs): Ki-M1p, MAC387, HAM56, LN5, KP1 (CD68), PG-M1 (CD68), Ki-M4p, DAKO-DRC (CD35), and antibodies against lysozyme, alpha 1-antichymotrypsin, and S100 protein. The French-American-British (FAB) classification subtypes of the AML cases, as determined by enzyme-cytochemical and/or immunocytological investigation of bone marrow smears, were as follows: M1 = 6, M2 = 5, M4 = 7, M5 = 3, and AML (not classified) = 2. The 13 cases of ALL were classified as follows: c-ALL (pre-B-ALL) = 7, B-ALL = 3, T-ALL = 2, and ALL (not classified) = 1. All the MAAs except LN5, Ki-M4p, and DAKO-DRC stained blast cells in AML. However, the number of stained blast cells varied considerably within and between the individual subtypes (M4/5 > M2/1). Using Fisher's exact test a significant difference in frequency of blast cell staining between AML and ALL was found for four MAAs (anti-lysozyme, MAC387, Ki-M1p, and KP1) and two of the three myeloid cell markers applied (Ki-My2p and anti-neutrophil elastase). Of these six antibodies, the combination of anti-lysozyme and KP1 can be recommended for use in routine diagnostics for the differentiation of AML from ALL on the basis of immunohistochemical staining because both of these antibodies were found to stain a relatively large percentage of cases of AML but none of ALL. However, none of the MAAs were found to discriminate reliably between the FAB M4/5 and M1/2 subtypes of AML.
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PMID:Assessment of the value of immunohistochemistry in the subtyping of acute leukemia on routinely processed bone marrow biopsy specimens with particular reference to macrophage-associated antibodies. 805 22

A 47-year-old man complaining of common cold-like symptoms was admitted to our hospital. Acute myelogenous leukemia was diagnosed and the patient was treated with induction chemotherapy. During granulocytopenia caused by induction chemotherapy, a nodular lesion appeared in the right upper lobe. The nodular lesion changed to a cavitary lesion after the recovery of peripheral white blood cell counts. A transbronchial biopsy specimen obtained from the right B3b showed Aspergillus. Oral itraconozole, flucytosine, and intravenous amphotericin B were given. The cavitary lesion in the right upper lobe regressed after anti-fungal therapy was started. During granulocytopenia caused by consolidation chemotherapy, the nodular lesion enlarged again. Thereafter, as bone marrow recovered, it changed to a cavitary lesion with a lung ball inside. In both episodes, a nodular lesion appeared during granulocytopenia, and changed to a cavitary lesion after bone marrow recovery. In addition, the level of neutrophil elastase reached its maximum at the time of the bone marrow recovery. These findings suggest that white blood cells of the host as well as neutrophil elastase play an important role in cavitation in pulmonary aspergillosis.
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PMID:[Invasive pulmonary aspergillosis in a patient with acute leukemia--the role of neutrophil elastase in in cavity formation]. 869 69

The genes encoding Hoxa9 and Meis1 are transcriptionally coactivated in a subset of acute myeloid leukemia (AML) in mice. In marrow reconstitution experiments, coexpression of both genes produces rapid AML, while neither gene alone generates overt leukemia. Although Hoxa9 and Meis1 can bind DNA as heterodimers, both can also heterodimerize with Pbx proteins. Thus, while their coactivation may result from the necessity to bind promoters as heterodimers, it may also result from the necessity of altering independent biochemical pathways that cooperate to generate AML, either as monomers or as heterodimers with Pbx proteins. Here we demonstrate that constitutive expression of Hoxa9 in primary murine marrow immortalizes a late myelomonocytic progenitor, preventing it from executing terminal differentiation to granulocytes or monocytes in the presence of granulocyte-macrophage colony-stimulating factor (GM-CSF) or interleukin-3. This immortalized phenotype is achieved in the absence of endogenous or exogenous Meis gene expression. The Hoxa9-immortalized progenitor exhibited a promyelocytic transcriptional profile, expressing PU.1, AML1, c-Myb, C/EBP alpha, and C/EBP epsilon as well as their target genes, the receptors for GM-CSF, G-CSF, and M-CSF and the primary granule proteins myeloperoxidase and neutrophil elastase. G-CSF obviated the differentiation block of Hoxa9, inducing neutrophilic differentiation with accompanying expression of neutrophil gelatinase B and upregulation of gp91phox. M-CSF also obviated the differentiation block, inducing monocytic differentiation with accompanying expression of the macrophage acetyl-low-density lipoprotein scavenger receptor and F4/80 antigen. Versions of Hoxa9 lacking the ANWL Pbx interaction motif (PIM) also immortalized a promyelocytic progenitor with intrinsic biphenotypic differentiation potential. Therefore, Hoxa9 evokes a cytokine-selective block in differentiation by a mechanism that does not require Meis gene expression or interaction with Pbx through the PIM.
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PMID:Hoxa9 immortalizes a granulocyte-macrophage colony-stimulating factor-dependent promyelocyte capable of biphenotypic differentiation to neutrophils or macrophages, independent of enforced meis expression. 1075 11

Leukemia is observed with increased frequency in patients with severe congenital neutropenia (SCN). In the past decade, recombinant human granulocyte colony-stimulating factor (rh G-CSF) has prolonged the survival of patients with SCN increasingly reported to have leukemias. In this communication acute myelogenous leukemia (AML) associated with a mutation of the G-CSF receptor (G-CSF-R) developed in a patient with SCN maintained on long-term G-CSF therapy. The blast count in the blood and bone marrow fell to undetectable levels twice on withholding G-CSF and without chemotherapy administration, but the mutant G-CSF-R was detectable during this period. The patient subsequently underwent successful allogeneic bone marrow transplantation. After transplantation, the patient's neutrophil elastase (ELA-2) mutation and G-CSF-R mutation became undetectable by polymerase chain reaction. This report provides novel insights on leukemia developing in congenital neutropenia.
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PMID:Spontaneous remission of granulocyte colony-stimulating factor-associated leukemia in a child with severe congenital neutropenia. 1107 67

Severe congenital neutropenia is a heritable human disorder characterized by neutropenia and acute myelogenous leukemia. We recently determined that the majority of cases result from de novo or autosomal dominantly inherited heterozygous mutations in ELA2, encoding neutrophil elastase. Neutrophil elastase is a chymotryptic serine protease localized in granules of neutrophils and monocytes and is the major target of inhibition of the serpin alpha(1)-antitrypsin. The mutations causing severe congenital neutropenia consist of amino acid missense substitutions, in-frame deletion, splice donor mutation producing a deletion, splice acceptor mutation causing insertion of novel residues, and protein truncating mutations of the carboxyl terminus resulting from nonsense substitutions and deletions leading to frameshifts. We have expressed 14 mutant forms of neutrophil elastase in vitro and have characterized their biochemical properties. The mutations have variable effects on proteolytic activity, eliminating the possibility that the disease results from haploinsufficiency. There is no evidence that the mutant enzymes are cytotoxic. The mutant enzymes retain vulnerability to inhibition by alpha(1)-antitrypsin, but demonstrate variable avidity for interaction with this serpin. Somewhat surprisingly, the mutant enzymes inhibit the wild type enzyme when both are coexpressed within the same cell, suggesting the potential to interfere with normal subcellular trafficking or post-translational processing.
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PMID:Characterization of mutant neutrophil elastase in severe congenital neutropenia. 1127 53

Severe congenital neutropenia (SCN) is a syndrome characterized by an isolated block in granulocytic differentiation and an increased risk of developing acute myeloid leukemia (AML). Recent studies have demonstrated that the majority of patients with SCN and cyclic neutropenia, a related disorder characterized by periodic oscillations in the number of circulating neutrophils, have heterozygous germline mutations in the ELA2 gene encoding neutrophil elastase (NE). To test the hypothesis that these mutations are causative for SCN, we generated transgenic mice carrying a targeted mutation of their Ela2 gene ("V72M") reproducing a mutation found in 2 unrelated patients with SCN, one of whom developed AML. Expression of mutant NE mRNA and enzymatically active protein was confirmed. Mice heterozygous and homozygous for the V72M allele have normal numbers of circulating neutrophils, and no accumulation of myeloid precursors in the bone marrow was observed. Serial blood analysis found no evidence of cycling in any of the major hematopoietic lineages. Rates of apoptosis following cytokine deprivation were similar in wild-type and mutant neutrophils, as were the frequency and cytokine responsiveness of myeloid progenitors. The stress granulopoiesis response, as measured by neutrophil recovery after cyclophosphamide-induced myelosuppression, was normal. To define the leukemogenic potential of V72M NE, a tumor watch was established. To date, no cases of leukemia have been detected. Collectively, these data suggest that expression of V72M NE is not sufficient to induce an SCN phenotype or leukemia in mice.
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PMID:Mice expressing a neutrophil elastase mutation derived from patients with severe congenital neutropenia have normal granulopoiesis. 1238 20

There are several common themes that are emerging from our expanding knowledge about the inherited bone marrow failure syndromes. Patients have a spectrum of birth defects, which are relatively characteristic for each syndrome. but overlap in features such as poor growth. radial ray anomalies, and involvement of skin, eyes, renal, cardiac, skeletal, and other organs. Within each syndrome the composition and severity of the physical phenotype varies widely, and it may require the astute observer to make the correct diagnoses in the milder cases. There is also a wide spectrum to the hematologic picture. These range from single cytopenias such as DBA, SCN, and TAR, which do not develop pancytopenia, to SD and Amega patients who begin with deficiency of a specific single lineage, but evolve to aplastic anemia, to patients with FA or DC, who may present with a deficiency of any one of the cell lines, but almost inevitably end up with full-blown aplastic anemia. Acute myeloid leukemia has been observed in FA, DBA, DC, SD, SCN, and Amega, although not yet in TAR patients. MDS has also been reported in all of the same disorders as AML, although whether it is a preleukemic condition or an independent bone marrow dyspoiesis is not yet clear. Solid tumors are also now appearing in patients whose underlying disease involves hematopoiesis and physical development. These tumors occur at much younger ages than in the general population, in patients who do not appear to have the usual risk factors, and have patterns that are characteristic to the syndrome, such as head and neck and gynecologic cancers in FA and DC, and osteogenic sarcomas in DBA. The other syndromes have not yet been reported to have a propensity for solid tumors. Several genes have been identified that are mutant in some of the syndromes, although the pathophysiology is still not entirely clear. The inheritance patterns include X-linked recessive, autosomal dominant, autosomal recessive, and even mitochondrial. The FA gene products appear to cooperate, and are important in the pathways involved in response to DNA damage. However, the role of this pathway in developmental defects, hematopoietic failure, and the specific malignancies in FA is not fully elucidated. The DC gene products are important for maintenance of telomere length, which may have relevance to development of aplastic anemia and malignancies, but the relation to the physical phenotype is less apparent. The role of mutations in c-mpl in Amega is more straightforward. since the gene codes for the receptor for thrombopoietin. which is the hormone required for megakaryocyte and platelet development; patients with mutant c-mpl do not have birth defects. The role of mutations in RPS19 in erythropoiesis or developmental defects in DBA patients is not obvious, and the increased frequency of osteogenic sarcomas suggests that at least that subset of patients may have a mutant tumor suppressor gene (such as p53, the mutant gene in Li-Fraumeni syndrome) [68]. Although patients with SCN have mutations in neutrophil elastase, patients with similar mutations may have relatively benign cyclic neutropenia, or may even have normal neutrophil levels [69,70]. The mitochondrial gene deletions in Pearson's Syndrome result in variable degrees of acidosis, and varied organ involvement due to heteroplasmy. Thus, the disorders included under the rubric "inherited bone marrow failure syndromes" have clinical. hematologic, oncologic, and genetic diversity.
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PMID:Bone marrow failure syndromes in children. 1243 Jun 21


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