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)

We recently described an IL-1 inhibitor found in urine of febrile patients. It is a 26-kDa glycoprotein that acts by blocking the binding of IL-1 to its receptor. In a search for a cell source for the urinary IL-1 inhibitor, we tested three promyelocytic cell lines, H-161, AML-193, and HL-60, for their ability to produce this protein. Under normal culture conditions none of these cell lines produce detectable IL-1 inhibitory activity. The H-161 cells were treated with differentiation-inducing agents, i.e., sodium butyrate, hemin, retinoic acid, DMSO, vitamin D3, and PMA alone or in combination with IL-1 alpha, IL-2, IL-3, IL-4, IL-5, IL-6, TNF-alpha, IFN-gamma, granulocyte-CSF, macrophage-CSF, granulocyte/macrophage-CSF (GM-CSF), and Con A and tested for the production of IL-1 inhibitor. Production of IL-1 inhibitor was detected in cell supernatant, when H-161 cells were differentiated to adherent macrophage-like cells under the influence of PMA followed by a second signal provided by GM-CSF. Treatment of the other two cell lines, AML-193 and HL-60, with PMA plus GM-CSF also yielded similar IL-1 inhibitor protein. Partial purified H-161-derived IL-1 inhibitor showed specific binding to IL-1R-bearing cells and blocked the binding of IL-1 to its receptor and is thus similar to the urinary-derived molecule. We conclude the GM-CSF provides a signal to adherent macrophage-like cells to become "inhibitory macrophages" and to produce a competitive inhibitor of IL-1.
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PMID:Human granulocyte-macrophage colony-stimulating factor plus phorbol myristate acetate stimulate a promyelocytic cell line to produce an IL-1 inhibitor. 214 81

Native human granulocyte-macrophage colony stimulating factor (hGM-CSF) has previously been purified using methods which typically required several sequential chromatographic steps and only yielded small amounts of hGM-CSF. We have purified and characterized hGM-CSF using monoclonal antibodies raised against bacterially synthesized hGM-CSF. Activated donor T-lymphocytes grown in interleukin-2 and then reactivated with phytohemagglutinin produce several forms of hGM-CSF which can be purified using immunoaffinity absorption followed by reversed phase high performance liquid chromatography. The purified hGM-CSF consisted of at least nine species ranging in molecular weight (Mr) from 14,500 to 32,000. The higher Mr forms contained one or two N-linked carbohydrate moieties and were more acidic by two-dimensional Western blot analysis, consistent with increasing sialation. N-terminal sequence analysis of high and low molecular weight hGM-CSF fractions corresponded to that predicted by the cDNA sequence. Using the AML 193 [3H]thymidine incorporation assay the specific activity of the heavily glycosylated hGM-CSF was 1 x 10(8) units/mg compared with 6 x 10(8) units/mg for the non-glycosylated hGM-CSF produced by Escherichia coli. The different hGM-CSF forms induced neutrophil superoxide anion production by a variable amount depending on the extent of N-linked glycosylation. Receptor binding studies demonstrated lower receptor affinity for the heavily glycosylated form (KD = 820 pM) compared to less heavily glycosylated (KD = 78 pM) and non-glycosylated hGM-CSF produced by E. coli (KD = 30 pM). These differences are due to differences in the kinetic association rate.
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PMID:Granulocyte-macrophage colony stimulating factor from human lymphocytes. The effect of glycosylation on receptor binding and biological activity. 215 31

Granulocyte macrophage colony-stimulating factor (GM-CSF) and interleukin-3 (IL-3) control the proliferation of human acute myeloid leukemia (AML) cells in vitro. Previously, we have shown that receptors for GM-CSF and IL-3 are often coexpressed on AML cells. Here we present experiments with purified AML blasts, normal monocytes, and granulocytes that were conducted to analyze the properties of GM-CSF and IL-3 binding proteins in more detail. On AML cells from eight cases we demonstrate two types of GM-CSF receptors: one with low affinity (dissociation constant [kd] 5.1 to 24.8 nmol/L) and one with a high affinity (kd 31 to 104 pmol/L). These AML cells also expressed high affinity receptors for IL-3 (kd 24 to 104 pmol/L). Cross-competition experiments showed that an excess concentration of nonlabeled IL-3 completely prevented the high affinity binding of radiolabled GM-CSF. This competition occurred at 37 degrees C as well as 4 degrees C. Low affinity GM-CSF binding was not affected by IL-3. Binding of radiolabeled IL-3 could be prevented by nonlabeled GM-CSF. In certain cases, this competition was complete, whereas in others only partial (49% to 77%) reduction of the radiolabeled IL-3 binding was seen. On the basis of these ligand binding features, we propose the existence of three receptor types on AML cells: (1) low affinity GM-CSF receptors that do not bind IL-3, (2) dual high affinity GM-CSF/IL-3 receptors, and (3) high affinity IL-3 receptors that do not bind GM-CSF. We could also demonstrate these receptor types on normal monocytes. In addition, a fourth type of receptor was apparent on normal granulocytes (4), incapable of binding IL-3 and with an intermediate affinity for GM-CSF (approximately 400 pmol/L). Chemical crosslinking showed that GM-CSF and IL-3 both bind to proteins with molecular weight values of 130, 105, and 75, which provides additional evidence for the existence of a common GM-CSF/IL-3 receptor complex.
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PMID:Common binding structure for granulocyte macrophage colony-stimulating factor and interleukin-3 on human acute myeloid leukemia cells and monocytes. 215 80

We gave 4 days of high-dose Ara-C followed 2 days later by rHUGM-CSF (which continued until the neutrophil count was greater than 1000/microliters) to 12 patients with newly diagnosed AML and a relatively poor prognosis. Six CRs occurred, there were four deaths during induction, and in only one case was there an rHUGM-CSF-associated growth of leukemia. The pattern of hematologic recovery was variable but in some patients rHUGM-CSF seemed to accelerate normal myelopoiesis following chemotherapy. Continued investigation of rHUGM-CSF and chemotherapy in AML is warranted.
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PMID:Treatment of poor-prognosis, newly diagnosed acute myelogenous leukemia with high-dose cytosine arabinoside (Ara-C) and rHUGM-CSF. 218 63

As part of a multicenter trial 12 patients with myelodysplastic syndromes (MDS) were treated with 14-day-cycles of recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF; 250 micrograms/m2 day s.c.). In addition, all patients received 20 mg/m2/day s.c. cytosine-arabinoside (Ara-C) 12 h after GM-CSF except for patients suffering from refractory anemia (RA) according to FAB classification. Courses were repeated after 4 weeks. In 11 evaluable patients, results according to FAB-classified MDS were as follows: RA, 1/2 response (R), 1/2 stable disease (SD); RAEB, 2/3 R, 1/3 SD; RAEB-T, 1/6 CR, 1/6 PR, 2/6 R, 2/6 progression; CMML, 1/2 SD. In 2 patients with RAEB-T, overt acute myeloid leukemia was observed 2 and 10 weeks after initiation of treatment. With few exceptions, treatment resulted in a prompt increase in granulocytes and eosinophiles. This was associated with improvement of infectious complications. Increases in red cells and platelets occurred variably and was apparently associated with responses of the underlying disease. Dose limiting side effects consisted of fever, severe fatigue and dolent local reactions at the site of GM-CSF injection. In addition, nausea and diarrhoea occurred frequently. Less often, respiratory and cardiovascular side effects were encountered. In summary, GM-CSF +/- Ara-C in MDS results in objective remission with manageable toxicity. Conceivably, this regimen will serve as a base for future treatment strategies against MDS.
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PMID:Recombinant human granulocyte-macrophage colony-stimulating factor and low-dose cytosine-arabinoside in the treatment of patients with myelodysplastic syndromes. A phase II study. 218 22

To investigate possible mechanisms of growth factor expression in acute myeloid leukemia, genes for granulocyte macrophage colony-stimulating factor (GM-CSF) were analyzed by Southern blots in 20 patients, for M-CSF in 13, for interleukin-6 (IL-6) in 14, for IL-6 receptor in 14 and for G-CSF in five patients. Only in one patient a complex rearrangement of the G-CSF gene with possible amplification was noted indicating rarity of direct alterations of growth factor genes in acute myelogenous leukemia (AML). Spontaneous m-RNA expression for GM-CSF was found in only one of 20 patients, and for IL-6 in eight of 11 patients. In vitro incubation of AML cells of eight patients with recombinant tumor necrosis factor for 24 hr revealed induction of GM-CSF m-RNA expression in three cases and GM-CSF protein expression in two of them. These data suggest that spontaneous GM-CSF production occurs rarely in AML and that monokines, such as tumor necrosis factor, may induce GM-CSF in AML cells. Therefore, interactions of AML cells with normal or malignant accessory cells may be important for autocrine stimulation in AML. Our data suggest that ectopic growth factor secretion is not the primary cause of generating AML but may contribute to progression of the disease. Alternatively, AML may represent a heterogenous group of leukemias with different etiology but similar phenotype.
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PMID:Mechanisms of growth factor expression in acute myeloid leukemia (AML). 219 15

Equilibrium binding of 125I-labeled recombinant granulocyte macrophage colony-stimulating factor (GM-CSF) to the blast cells of acute myeloblastic leukemia (AML) revealed the presence of two classes of binding components of high and low affinity, with dissociation constants (Kd) in the range of 5-10 pM and 1-10 nM, respectively. Specificity studies revealed that interleukin-3 (IL-3) could partially inhibit the binding of GM-CSF to AML blasts and to the cells of the leukemic lines M07-E, KG-1, and HL-60. The inhibition of GM-CSF binding by IL-3 was directly dependent on the presence of IL-3 receptors. Analysis of competition curves indicated that the Kd and the number of binding sites per cell of unlabeled and iodinated GM-CSF were identical. In contrast, the inhibition of GM-CSF binding by IL-3 was mediated by IL-3 occupancy of a high affinity receptor only, with the same number of sites as the high affinity GM-CSF receptor but a slightly higher Kd. Despite this competitive binding, IL-3 augmented AML blast proliferation in the presence of GM-CSF, indicating that the two growth factors have converging pathways in supporting blast proliferation. In striking contrast to AML blasts, GM-CSF binding to neutrophils was compatible with the presence of only one class of binding site of intermediate affinity (Kd approximately 100-160 pM). Furthermore, IL-3 does not compete for the binding of GM-CSF to neutrophils.
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PMID:IL-3 inhibits the binding of GM-CSF to AML blasts, but the two cytokines act synergistically in supporting blast proliferation. 220 26

Human acute myelocytic leukemia (AML) marrow cells respond to stimulation with increased proliferation and enhanced intracellular metabolism of the cytotoxic antimetabolite 1-B-D arabinofuranosylcytosine (ara-C). Our previous studies have focused on the drug-induced humoral stimulatory activity (HSA) present in serum following initial cytoreduction which augments in vitro growth and biochemical pharmacology. The activity of HSA likely relates to the presence of multiple stimulators. The effect of 18-hr culture in purified recombinant human granulocyte-macrophage colony stimulating factor (rhGM-CSF) (1 ng/ml) on in vitro AML marrow cell [3H]dThd incorporation into DNA, intracellular ara-C activation to the triphosphate form (ara-CTP), and subsequent ara-CTP retention were determined in leukemic cells of 11 patients and compared with cells similarly cultured in HSA-containing sera. The stimulatory effects of rhGM-CSF and HSA on both growth and pharmacologic parameters were comparable for each AML population, with maximal response to both regulators detected for FAB M2. These data demonstrate that GM-CSF acts similarly to HSA as an active stimulator of leukemic cell proliferation and net intracellular ara-C metabolism in vitro, and support clinical trials designed to examine the role of rhGM-CSF in enhancing ara-C cytotoxicity by increasing the growth fraction of drug-responsive target cells in vivo.
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PMID:Effects of rhGM-CSF on intracellular ara-C pharmacology in vitro in acute myelocytic leukemia: comparability with drug-induced humoral stimulatory activity. 220 33

Interleukin-1 (IL-1) has hemopoietin-1 (H-1) activity, i.e., it synergizes with macrophage-colony stimulating factor (M-CSF), granulocyte-macrophage-CSF (GM-CSF) and interleukin-3 (IL-3) in stimulating in vitro colony formation of hematopoietic progenitor cells. In this study the synergistic activity of IL-1 was investigated on IL-3 and GM-CSF induced growth of acute myeloid leukemia colony forming cells (AML-CFU) in vitro. Among 12 cases of human AML, IL-1 significantly elevated IL-3 stimulated colony numbers in eight instances and enhanced GM-CSF induced colony growth in five cases. As IL-1 is an inducer of cytokine production and since tumor necrosis factor (TNF) elevates IL-3 or GM-CSF induced proliferation of AML-CFU, we examined whether IL-1 enhanced AML-CFU growth via the induction of TNF production. Neutralizing anti-TNF-alpha antibodies significantly decreased IL-1/IL-3 or IL-1/GM-CSF stimulated colony numbers in six of seven cases studied, whereas anti-TNF-beta had no effect, indicating that endogenously produced TNF-alpha costimulated the growth of AML-CFU. Furthermore, AML blast cells stimulated by IL-1 released increased amounts of TNF-alpha (between 25 and 533 pg/ml; median 255 pg/ml) into the culture medium (TNF-alpha specific radioimmunoassay) as compared with noninduced AML cells (less than 1 to 149 pg TNF-alpha/ml; median 31 pg/ml). Thus, the effect of IL-1 on AML-CFU proliferation is not the result of direct activation of AML progenitors, but IL-1 stimulates the release of TNF-alpha by AML cells and endogenous TNF subsequently synergizes with IL-3 or GM-CSF.
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PMID:Hemopoietin-1 activity of interleukin-1 (IL-1) on acute myeloid leukemia colony-forming cells (AML-CFU) in vitro: IL-1 induces production of tumor necrosis factor-alpha which synergizes with IL-3 or granulocyte-macrophage colony-stimulating factor. 220 34

A study of bone marrow stromal elements in murine acute myeloid leukemia (AML) was carried out. Our previous studies had indicated marrow stromal deficiency in murine AML. In the current investigation, separate stromal cells were cultured and the results obtained have shown that, while marrow stromal macrophages are normal in leukemia and express adequate amounts of IL-1, the fibroblasts are markedly reduced. However, if sufficient fibroblasts are pooled in vitro, they produce adequate amounts of CSF. Test of TNF alpha in leukemic cells CM, as possible cause of marrow stromal inhibition in leukemia, had not disclosed this cytokine. Further, it was observed that total body lethal irradiation of leukemic mice aggravates the stromal deficiency, confirming results of our previous investigations. It is concluded that bone marrow stromal deficiency in murine AML is due to decreased fibroblasts and, implicitly, reduced CSF production.
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PMID:Bone marrow stromal elements in murine leukemia: decreased CSF-producing fibroblasts and normal IL-1 expression by macrophages. 222 38


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