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

Somatostatin (SS) is a 14 amino acid peptide which is secreted by the hypothalamus and the pancreatic islets. It expresses antiproliferative activity in various organ systems, experiments have suggested effects of SS on hematopoietic cells. Here we present investigations regarding the effect of SS and its analog SMS 201-995 (SMS) on the in vitro proliferation of acute lymphoblastic leukemia (ALL; n = 7 cases), acute myeloid leukemia (AML; n = 21 cases) and chronic lymphocytic leukemia (CLL; n = 2 cases). Both SS and SMS inhibited spontaneous leukemic cell growth in approximately 1/3 of cases (i.e. 7/19). G-CSF stimulated AML cells were inhibited by SMS in 11/21 cases. AML cell proliferation induced by IL-3 or GM-CSF was suppressed in only 3/21 and 6/21 cases, respectively. In ALL cells, IL-7-induced proliferation was suppressed by SMS in 3/7 cases. The effect of SMS seemed to depend on the type of the hematopoietic growth factor, and on their concentrations. In fact, high concentrations of G-CSF could override SMS blocking completely. Colony formation by normal marrow progenitors and DNA synthesis by HL-60 and T11/65 leukemic cell lines were not affected by SMS. In conclusion, somatostatin may act as a negative regulator of the proliferative activity of human leukemia.
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PMID:Somatostatin and its cyclic octapeptide analog SMS 201-995 as inhibitors of proliferation of human acute lymphoblastic and acute myeloid leukemia. 750 Jun 46

A 75-year-old man developed a cluster of differentiation (CD)4-positive but human T-cell lymphotropic virus type I (HTLV-I)-negative T lymphoid neoplasm with overwhelming cutaneous involvement and mild thrombocytosis. Twelve courses tetrahydropyranyl adriamycin, cyclophosphamide, vincristine and prednisone (THP-COP) combination chemotherapy led him to complete remission. After four months of complete remission, however, atypical immature cells (blasts) appeared in peripheral blood and bone marrow. Surface marker analysis revealed the blasts to be CD2-, CD3-, CD4-, CD5-, CD7+, CD8-, CD10, CD13 +/-, CD19-, CD20-, CD25-, CD33+ and human leukocyte antigen-DR (HLA-DR+). Staining for myeloperoxidase, esterases, PAS and platelet peroxidase were all negative. The patient was diagnosed as having both CD7 and CD33 positive acute myeloid leukemia (AML). The relation between the T cell lymphoid neoplasm and AML was not clear. Thrombocytosis became more marked after acute leukemia occurred and the platelet count varied in parallel with the blast cell count in peripheral blood. When the leukemic cell count was high, thrombopoietic activity could be detected in the serum. In addition, conditioned medium obtained from primarily-cultured blasts had detectable thrombopoietic activity, which implied the blasts directly to produce a thrombopoietic factor(s). Analysis of the serum concentration for cytokines with associated thrombopoietic activity indicated that the blasts possibly produced a thrombopoietic factor(s) distinct from interleukin (IL)6, IL3, leukemia inhibitory factor (LIF), erythropoietin and granulocyte macrophage-colony stimulating factor. To our knowledge, this is the first reported case of an acute myeloid leukemia with marked thrombopoiesis (more than 2000 x 10(3)/microliter of maximum platelet count in peripheral blood.
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PMID:Acute myeloid leukemia possibly producing thrombopoietic factor(s). 750 2

Acute myelogenous leukemia is characterized by the infinite proliferation of malignant leukemia cells and by the impaired hematopoiesis. The proliferation of leukemia cells is supported by a small subpopulation, leukemic blast progenitors. Leukemic blast progenitors make leukemic blast colonies in methylcellulose culture. To determine the mechanism by which leukemia cells proliferate, we studied the role of several cytokines in the proliferation of leukemic blast progenitors in vitro. The findings indicated that there are at least three types in the regulation by cytokines of the leukemic cell growth. One is the stimulation of leukemic blast progenitors by colony-stimulating factors(CSFs) or interleukins(ILs) added in culture. These cytokines include granulocyte-CSF(G-CSF), granulocyte-macrophage CSF (GM-CSF), IL-3 and IL-1. The second is the autocrine growth mechanism. Leukemia cells by themselves produce and secrete G-CSF and GM-CSF, which stimulate the growth of leukemic blast progenitors. The third is a complex mechanism. IL-1, produced by leukemia cells or other cells, enhances the production of GM-CSF by leukemia cells, which stimulates the growth of leukemic blast progenitors. The precise mechanism by which each cytokine acts on leukemic blast progenitors should be determined to explore the mechanism of leukemia cell growth.
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PMID:[The role of cytokines in the proliferation of leukemia cells in acute myelogenous leukemia]. 750 32

Tumor necrosis factor (TNF) is a major regulator of AML growth in vitro and markedly enhances AML growth induced by GM-CSF/IL-3. TNF, on the other hand, suppresses the G-CSF stimulated AML cell proliferation and serves as a modulator of growth factor receptors on AML cells. It upregulates GM-CSF and IL-3 receptors by a mechanism which depends on new protein synthesis and downregulates G-CSF receptors by activation of protein kinase C (PCK). The leukemic cells from patients with acute or chronic leukemias have similar TNF receptor structures (MW 76 kD). Serum TNF levels increase in patients with both acute and chronic leukemias especially in those with advanced disease. The clinical application of TNF in association with GM-CSF or IL-3 may be of value for patients with AML.
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PMID:Tumor necrosis factor and human acute leukemia. 751 20

The effects of six recombinant human cytokines: erythropoietin, GM-CSF, G-CSF, interleukin-3, -4 and -6 on the proliferation and differentiation of a human multilineage myeloid leukemia cell line MHH 225, established from the bone marrow of an AML(M7) patient in our laboratory determined by changes in antigen expressions using monoclonal antibodies in APAAP technique were examined in liquid suspension culture. The MHH 225 cells have been growing exponentially without cytokines or conditioned media. About 90 per cent of MHH 225 cells are CD33+ CD34+ CD3- CD7- CD19- CD20- TdT- with 57.6 per cent, 28.3 per cent and 7.8 per cent of them being CD41+, glycophorin A+ and CD15+, respectively. After five days of treatment with erythropoietin, GM-CSF, G-CSF or IL-6 no change was observed in MHH 225 cell antigens expression. IL-3 (100 U/ml) induced a moderate increase in only CD13 and alpha naphthyl esterase positive cells from 6.5 +/- 1.9 per cent and 5.7 +/- 2.4 per cent in control cultures to 21.6 +/- 3.0 per cent and 19.1 +/- 2.8 per cent, respectively. On the other hand, 100 U/ml IL-4 significantly increased the number of CD13, CD15 and alpha naphthyl esterase positive cells to 48.9 +/- 5.0 per cent, 47.2 +/- 3.6 per cent and 46.1 +/- 3.0 per cent, p < 0.001, respectively. Also, 100 U/ml IL-4 decreased the number of CD41 positive cells from 57.6 +/- 2.8 per cent to only 25.9 +/- 3.6 per cent and did not change the number of CD33 or glycophorin A positive cells. The present results showed that out of the six myelopoietic growth factors tested, IL-4 was the only one to inhibit selectively the proliferation of CD33+ CD41+ leukemic megakaryoblast cells suggesting that IL-4 may have a lineage regulatory effect in favour of a myeloblastic CD33+ CD13+ CD15+ at the expense of a megakaryoblastic CD33+ CD41+ amplification in human leukemia cells and with apparently no effect on leukemic erythroblast cells. The MHH 225 cell line provides a useful tool and freely available model to scientists for studying signal transduction via IL-4 and for studies of 'lineage switch'.
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PMID:Interleukin-4 inhibits proliferation of human leukemic megakaryoblast cell line MHH 225. 752 Aug 82

A novel human CD7-positive leukemia cell line (HSM911) derived from the peripheral blood of a patient with acute myelogenous leukemia (AML) was studied for its cellular and biological characterization. Proliferation assay using a variety of cytokines demonstrated that the HSM911 cells proliferate in response to recombinant granulocyte-macrophage-colony stimulating factor (rGM-CSF), recombinant Interleukin-3 (rIL-3) and recombinant stem cell factor (rSCF), but do not in response to recombinant granulocyte-colony stimulating factor (rG-CSF), natural macrophage-colony stimulating factor (M-CSF), rIL-1, rIL-2, rIL-4, rIL-5, rIL-6 or recombinant erythropoietin (rEpo). Polyclonal anti-GM-CSF antibody and polyclonal anti-IL-3 antibody blocked the proliferation of HSM911 stimulated with rGM-CSF and rIL-3, respectively. HSM911 maintained in the presence of rGM-CSF expressed the CD7, CD13, CD33, CD34, CD41a, HLA-DR, VLA1-VLA5, CD11a, CD54, CD44 and LAM1. These findings suggest that HSM911 might be of multipotent progenitor cell origin. GM-CSF receptors and rIL-3 receptors expressed on this cell line were simultaneously suppressed by rGM-CSF or rIL-3, whereas only IL-3 receptors were down-modulated by rSCF. Treatment with 12-o-tetradecanoyl-phorbol-13-acetate (TPA) induced the differentiation of HSM911 cells into macrophage-like cells but not erythroblasts, megakaryocytes or lymphocytes. Interferon-gamma and transforming growth factor-beta (TGF-beta) suppressed the proliferation of HSM911 cells in a dose dependent manner. HSM911 was relatively resistant against anti-cancer drugs compared with fresh AML cells and other leukemic cell line. HSM911 is a useful tool for analyzing CD7-positive acute myelogenous leukemia.
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PMID:[Cellular and biological characterization of CD7-positive acute leukemia cells--an investigation of the established cell line, HSM911]. 752 34

The application of hematopoietic growth factors in the treatment on acute myeloid leukemia (AML) may principally aim at shortening the period of treatment associated neutropenia and reducing the rate of infectious complications by their post-therapeutic administration but may also be used to increase the sensitivity of leukemic blasts to antileukemic therapy by pretherapeutic growth stimulation. Both aspects were addressed in subsequent clinical phase II studies and preclinical investigations. In a first clinical trial, 36 patients with high-risk AML received granulocyte-macrophage colony-stimulating factor (GM-CSF) after successful cytoreductive chemotherapy and experienced a shortening of the period of post-therapeutic neutropenia by 6 to 9 days, leading to a significant reduction of treatment-associated deaths from 39% to 14%. In preclinical studies an enhancement of the cytotoxicity of cytosine arabinoside (AraC) on leukemic blasts could be shown by pretreatment with GM-CSF or IL-3. Investigations on the impact of hematopoietic growth factors on the intracellular metabolism of AraC indicated that this effect was primarily mediated by an increase in the activity of DNA-polymerase-alpha. The evaluation of different doses of AraC showed the most marked increase after the combination of GM-CSF with conventional rather than high doses of AraC. Based on these preclinical experiments, a prospective randomized trial was subsequently initiated investigating the effect of GM-CSF before and during induction, consolidation, and the first two cycles of maintenance chemotherapy in newly diagnosed AML. This ongoing trial has enrolled 67 patients at the current time. An early interim analysis showed no differences in remission rates but a tendency toward a longer remission duration in patients receiving GM-CSF. These data indicate that hematopoietic growth factors like GM-CSF in particular may provide a new perspective in the treatment of acute myeloid leukemia with the possibility of reducing treatment associated mortality and perhaps of increasing the efficacy of antileukemic treatment.
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PMID:New perspectives in the treatment of acute myeloid leukemia by hematopoietic growth factors. 752 49

We examined the responsiveness of leukemic cells to colony stimulating factors (CSFs) as determined by 3H-TdR incorporation and surface phenotypes of leukemic blasts. In acute myeloid leukemia (AML), CD13 and/or CD33 positive and HLA-DR negative M1 and M3 cases tended to show high response to G-CSF, GM-CSFs and IL-3, however, all HLA-DR positive M1, M2, M4 and M5 cases were unresponsive to CSFs but showed high autonomous growth. In acute lymphocytic leukemia (ALL), no response was observed to any CSFs but high autonomous growth was found in mixed leukemia cases. Sole T or B lineage cases showed low autonomous growth. These results suggest the varied nature of the proliferative state in leukemia and the existence of a subgroup in M1.
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PMID:Relationship between responsiveness to colony stimulating factors (CSFs) and surface phenotype of leukemic blasts. 870 27

Stem cell factor (SCF), a c-kit ligand, has a preferential effect on the proliferation of several classes of immature hematopoietic progenitor cells in combination with GM-CSF or IL-3. To analyze the costimulatory role of SCF in leukemic growth, we investigated the effect of SCF in the presence of GM-CSF and/or IL-3 on isolated CD34-positive (CD34+) leukemic blasts from 15 patients with acute myelogenous leukemia (AML). Cultures of CD34+ cells from normal bone marrow were used as controls. When the proliferation of CD34+ AML blasts in the presence of GM-CSF and/or IL-3 were evaluated in vitro for the effects of SCF, two patterns emerged. In one pattern, CD34+ AML blasts responded with a significant increase in DNA synthesis and/or colony formation when SCF was used with GM-CSF and/or IL-3 relative to the growth with SCF alone; This result is consistent with those CD34+ bone marrow cells from normal donors. Six patients (40%) were included in this category. The addition of SCF as a single factor resulted in colony formation in all six of these cases. In the other pattern, nine of the patients (60%) had CD34+ leukemic cells whose growth with SCF plus either GM-CSF, IL-3, or GM-CSF+IL-3, was not significantly different from the growth noted in the presence of SCF alone. Among them seven cases that did not form colonies in response to SCF alone, and one case showing autocrine, background growth were included. In the six cases in which the costimulating effects of SCF were documented, CD34+ c-kit+ blasts comprised 50.5 +/- 18.7% of the CD34+ leukemic blasts-higher than 21.8 +/- 19.4% of cases in which the costimulating effect of SCF was not documented. In the cases showing high c-kit antigen expression (> or = 40%), SCF had a costimulatory effect in 71% (5/7) of the patients. In conclusion, our data indicate that CD34+ leukemic blasts from a good proportion of patients with AML did not respond to the costimulating effects of SCF in the presence of GM-CSF adn/or IL-3, in contrast to those CD34+ bone marrow cells from normal donors. The possible use of SCF for acute leukemia must await further cytogenetic and molecular studies, which should clarify the preferential costimulating role of SCF in normal hematopoiesis.
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PMID:Differential responses of CD34-positive acute myelogenous leukemic blasts to the costimulating effects of stem cell factor with GM-CSF and/or IL-3. 753 32

The growth of human leukemic cells in culture and in vivo is dependent upon the presence of hematopoietic growth factors. Most populations of human leukemic acute myeloblastic leukemia (AML) cells express c-Kit on their surface and respond to Kit ligand (KL) in culture. To determine if this interaction was of potential significance in vivo we used a mouse model system. 32D cells, a murine IL-3-dependent myeloid cell line, were rendered KL responsive by transfection of the murine c-Kit. After injection of 32D or 32D-Kit cells into syngeneic hosts, animals bearing 32D-Kit cells, but not 32D cells, became moribund and were killed. These animals had circulating leukemic blast cells, infiltration of bone marrow, spleen, brain, liver, lung, and kidney. Cells recovered from some of the animals continued to be dependent upon IL-3 or KL for growth while in other cases the cells were factor independent. This model illustrates that the constitutive expression of c-Kit enhances the leukemic potential of 32D cells. The model will be useful for studying the progression of leukemia in vivo and testing whether interruption of the interaction of Kit and KL can affect the growth of leukemic cells.
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PMID:c-KIT expression enhances the leukemogenic potential of 32D cells. 753 53


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