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)

In a clinical phase II trial GM-CSF was applied to 23 patients with acute leukemias carrying a high risk of early death because of old age or advanced disease. Concomitant laboratory investigations included the analysis of colony assays for normal granulopoietic progenitors (CFU-GM) and leukemic CFU-L with and without the addition of GM-CSF, as well as DNA measurements by flow cytometry (FCM) for the detection of DNA-aneuploidies. The present analysis is focused on one particular patient with acute myeloid leukemia (AML) in whom the detection of a DNA aneuploidy provided the readily accessible means to monitor the response of leukemic blasts to induction chemotherapy and subsequent GM-CSF treatment in vivo complementing the colony assay analyses performed in vitro. Prior to therapy 60% of cells revealed a DNA aneuploidy with a DNA index of 1.26 and in-vitro exposure of leukemic bone marrow blasts to GM-CSF (100 U/ml) enhanced the growth of CFU-L and CFU-GM with a significantly higher stimulatory index for CFU-L (1:19 versus 1:5.5). Three days after the completion of two cycles of induction therapy with thioguanine, cytosine arabinoside and daunorubicin (TAD 9) a morphologic bone marrow evaluation revealed aplasia without leukemic blasts. By FCM DNA analysis, however, 8% residual aneuploid cells were found. No growth of CFU-L was observed at this time point neither spontaneously nor after the addition of GM-CSF which induced the growth of CFU-GM, only. In-vivo application of GM-CSF (250 micrograms/mg2/day by continuous 24-h infusion) led to the recovery of normal granulopoiesis without evidence of a concomitant stimulation of aneuploid leukemic cells. These data indicate a change in the susceptibility of leukemic blasts to GM-CSF before and after chemotherapy. A reduction of the leukemic cell burden below a critical level or a selection of GM-CSF non-responsive early leukemic precursor cells may account for these observations.
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PMID:Changing response of clonogenic myeloid leukemia blasts to granulocyte-macrophage colony-stimulating factor (GM-CSF) during anti-leukemic therapy--a case report on the basis of a clinical phase II trial. 218 81

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

1. Induction of tumor cell differentiation could reverse transformed cells into normal, mature cells. Important question is whether these malignant-to-normal reversed cells are really normal ones. 2. We have developed an experimental model based on the examination of three different levels of human acute myeloid leukemia cell properties before and after induction of differentiation: morphological (percentage of undifferentiated blast cells), functional (DNA ploidy, Fc receptors, phagocytic activity, clonogenic assay in soft agar, oxidative metabolism which accompanies phagocytosis in mature granulocytes) and genetical (expression of oncogene p53). 3. Several inducers have been employed: dimethylsulfoxide (DMSO) granulocyte-macrophage colony stimulating factor (GM-CSF); tunicamycin, interferon gamma, tumor necrosis factor and lipopolysaccharide. 4. Our results indicate that the reversion of leukemic cells into mature normal ones with some inducers (DMSO, GM-CSF) could be a complete process.
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PMID:Artificial reversion of acute myeloid leukemia cells into normal phenotype. 218 58

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

Chemotherapy (CT) induced critical neutropenia remains a major dose limiting problem in acute leukemias. In order to reduce the phase of risk we gave recombinant human GM-CSF to 30 patients at high risk of early death with acute myeloid leukemia (AML). 19 patients with untreated AML and 1 patient with AML late relapse were 65+ years of age and were treated for CT by the TAD9 regimen. 10 patients at all ages had AML early or second relapse and received S-HAM CT. Starting on day 4 after CT GM-CSF 250 micrograms/m2/d was given by continuous i.v. infusion until neutrophils recovered. GM-CSF reduced the median recovery time of neutrophils by 4 days in the TAD9 and 9 days in the S-HAM CT group when compared to controls. After the CT induced aplasia 3 patients with AML showed a regrowth of their blasts which after the stop of GM-CSF was reversible in 1 patient and unaffectedly continued in 2 patients. 57% of patients attained a complete remission, and the median age of the responders was 65 (34-84) years. Remission duration was not found to be reduced. Thus, GM-CSF reduces CT toxicity with a low risk of promoting the disease and may allow more effective antileukemic treatment.
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PMID:Recombinant human GM-CSF following chemotherapy in high-risk AML. 220 65

We studied the effect of preincubation with recombinant GM-CSF on the activity of cytarabine and doxorubicin against clonogenic acute myeloid leukemia cells (CFU-AML). Leukemia cells from seven persons with AML, three myeloid cell lines (HL60, KG1, K562) and two control cell lines (U937, MOLT3) were tested. Preincubation with GM-CSF (0.01-0.1 microgram/ml) increased DNA synthesis as measured by tritiated thymidine incorporation and intranuclear Ki67 expression in cells from six persons with AML and in HL60 cells. Leukemia cells preincubated with GM-CSF for 6-48 h were exposed to cytarabine (2-200 micrograms/ml) or doxorubicin (0.01-0.1 microgram/ml) for 3 h and CFU-AML assayed. This approach further reduced CFU-AML in samples from six persons with AML and in HL60 and KG1 cells compared to cells not preincubated with GM-CSF prior to drug treatment. In most instances, reduced CFU-AML correlated with GM-CSF induced DNA synthesis. These data suggest a possible strategy of GM-CSF pretreatment to increase anti-leukemia efficacy of chemotherapy in AML.
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PMID:GM-CSF incubation prior to treatment with cytarabine or doxorubicin enhances drug activity against AML cells in vitro: a model for leukemia chemotherapy. 223 47

In patients with acute myeloblastic leukemia incomplete response to induction chemotherapy and short disease-free survival may be related to cell kinetic quiescence of leukemic cells. In this in vitro study, we tested the hypothesis that treatment with cytokines and subsequent chemotherapy (ARA-C, daunorubicin) can increase proliferation and enhance leukemic cell kill. We evaluated the effects of recombinant human interleukin-3 (rh-IL-3), granulocyte-macrophage colony stimulating factor (rhGM-CSF) and granulocyte colony stimulating factor (rhG-CSF) alone and in combination on AML (N = 11) and blastic phase CML (N = 3) samples. Cellular DNA and RNA, incorporation of bromodeoxyuridine (BrdU), cell growth fraction, cell viability, and differentiation markers were evaluated in vitro. A decrease of the quiescent cell population (p = 0.003) and an increase in S-phase cells (p = 0.001) was observed in 8/11 AML samples treated with cytokine combinations. Pronounced heterogeneity or proliferative response was seen between individual cases and different cytokines, but in the majority of the samples IL-3 was most effective. Significantly increased Ki67 expression (p = 0.009) and BrdU incorporation (p = 0.01) were also found after exposure to cytokines indicating an increase in growth fraction. DNA synthesis time was unaffected. Eight samples of AML were treated for 24 hr with ara-C following 2 days of in vitro cytokine incubation. Evaluation of leukemic cell kill showed increased cytotoxicity in three of those five samples which had significant depletions of G0 cells and increases in S-phase. None of the leukemic samples without recruitment from G0 had an increase in ARA-C cytotoxicity. This study provides detailed cell kinetic analysis of cytokine effects on AML blasts and provides a rationale for a novel approach to the treatment of AML.
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PMID:Kinetic rationale for cytokine-induced recruitment of myeloblastic leukemia followed by cycle-specific chemotherapy in vitro. 224 6

The role of interleukin-1 (IL-1) as a regulator of the autonomous growth of the blast cells of acute myeloid leukaemia (AML) has been studied on samples isolated from 15 patients. In nine out of 10 patients with evidence of partial autonomous blast cell growth. IL-1 further stimulated cell growth in both suspension culture and in a clongenic assay. IL-1 also stimulated cell growth in two out of three cases with no evidence of autonomous growth whereas no additional stimulation was observed in two cases with totally autonomous growth. In blast cells stimulated by IL-1, synthesis of granulocyte-macrophage colony stimulating factor (GM-CSF) was increased and the proliferative response to IL-1 was inhibited by an antibody to GM-CSF. In all samples with evidence of autonomous growth, blast cell conditioned medium (BCCM) contained IL-1 activity (range 0.7-74.2 units ml) and a polyclonal antibody to IL-1 markedly inhibited autonomous growth in four samples. BCCM from three of these four samples contained GM-CSF, the synthesis of which was suppressed when BCCM was prepared in the presence of anti-IL-1. Our data suggests that endogenous IL-1 is an important factor in the regulation of the production of GM-CSF and hence of autonomous growth of AML blasts, but that other mechanisms regulating GM-CSF production may exist.
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PMID:Interleukin-1 is one factor which regulates autocrine production of GM-CSF by the blast cells of acute myeloblastic leukaemia. 226 11

The ability of human alveolar macrophages to support colony formation of precursor blast cells of the myeloid lineage was investigated. Myeloid blast cells were collected from patients with acute myeloid leukemia (AML), myelodysplastic syndrome (MDS) and from the livers of fetuses aborted in the second trimester of gestation. It was found that the alveolar macrophages (AM) produced sufficient amount of colony-stimulating activity which culminated in the fourth week of in vitro cultivation. Conditioned media from AM supported the growth of multipotential blast cell colonies (GEMM-CFU) in AML and MDS, while in fetal hemopoiesis macrophage colonies preponderated. Preincubation with human interferon-alpha (IFN-alpha) can abrogate the production of the granulocyte-macrophage colony stimulating factor (GM-CSF) by AM. Media conditioned by AM were not able to compensate for cell-to-cell contact in long-term cultures of AML blast cells but CSFs released from AM in vivo can contribute to aggravation of the disease.
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PMID:Release of granulocyte-macrophage colony-stimulating activity from human alveolar macrophages and its support of human myeloid blast cell proliferation. 227 85

Based on the results of preclinical and in vitro studies demonstrating enhanced granulocytic proliferation and differentiation induced by granulocyte-monocyte and granulocyte-colony stimulating factors (GM-CSF and G-CSF), these recombinant human haemopoietic growth factors have been used to treat cytopenic patients with myelodysplastic syndromes (MDS). Laboratory investigations have shown responsiveness of enriched haemopoietic precursors in vitro to the proliferative and granulocytic differentiative stimuli of G-CSF, generally without increased clonal regeneration. To date, five short-term phase I/II clinical trials using GM-CSF have demonstrated that 38 of 45 treated patients had improvements in neutrophil counts, 14 had increased reticulocyte counts, with three of these patients having decreased red blood cell transfusion requirements, and eight had a transient increase in platelets. In 12 patients an increase in marrow and/or peripheral blood blasts was noted. Seven patients progressed to acute myeloid leukaemia (AML), particularly patients with greater than 15% marrow blasts. In a longer term study, five patients received GM-CSF for two to nine weeks, although only one maintained increased neutrophil counts, one developed antibodies to GM-CSF and one's condition evolved into AML. Eighteen patients have been treated for two months in phase I/II clinical trials with G-CSF, 16 of whom had normalization of neutrophil counts with improved marrow maturation, five had increased reticulocyte counts with three having decreased transfusion requirements, four had transient increases in blasts and no substantial changes in platelet counts were noted. Eleven patients have received maintenance therapy with G-CSF for 6-16 months and 10 had persistent increases in neutrophil counts with enhanced marrow myeloid maturation. Decreased infectious episodes were noted in these patients at times at neutrophil improvements. Four of the 18 patients have subsequently developed AML after 6-16 months. Both CSFs were well tolerated, although the incidence of fever, myalgias and bone pain was more prominent in patients receiving GM-CSF at higher doses. In vitro correlates with these in vivo results were demonstrated as laboratory studies showed that G-CSF had greater myeloid differentiative and less proliferative effects for MDS marrow than did GM-CSF. Marrow cytogenetic studies after treatment generally indicated persistence of the initial normal and/or abnormal clones. These studies have demonstrated that both G-CSF and GM-CSF improve neutrophil counts in a high proportion of patients with MDS and that chronic administration of G-CSF elicits persistent neutrophil responses and may decrease infections. Phase III controlled trials are required to determine whether the natural history of this disorder will be altered by use of colony stimulating factors.
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PMID:The use of haemopoietic growth factors in the treatment of myelodysplastic syndromes. 227 14


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