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 tested the in vitro effect of a novel granulocyte colony-stimulating factor (G-CSF) derivative (KW-2228) on the growth of G-CSF-dependent hemopoietic progenitor cells: granulocyte precursor cells (CFU-G), leukemic blast progenitors freshly obtained from 9 patients with acute myeloblastic leukemia (AML) and cells of a G-CSF-dependent human AML cell line (OCI/AML 1a). KW-2228 showed a higher stimulating effect than recombinant human G-CSF (rhCSF) on CFU-G; 3 out of 9 leukemic blast progenitors and OCI/AML 1a cells. The difference in biochemical stability between rhG-CSF and KW-2228 was considered to explain the superior colony-stimulating activity of KW-2228. The results show that KW-2228 will be a new granulopoietic factor.
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PMID:Enhanced effect of mutant granulocyte-colony-stimulating factor (KW-2228) on the growth of normal and leukemic hemopoietic progenitor cells in comparison with recombinant human granulocyte-colony-stimulating factor (G-CSF). 138 43

Tumor necrosis factor (TNF)-alpha and TNF-beta have multiple effects on human acute myeloid leukemia (AML) cells in vitro, including (1) synergistic stimulation of proliferation with interleukin-3 (IL-3) and granulocyte-macrophage colony-stimulating factor (GM-CSF) and upregulation of interleukin-3 (IL-3) and GM-CSF receptors; (2) inhibition of granulocyte-CSF (G-CSF)-induced growth and rapid downmodulation of G-CSF receptors; and (3) induction of autocrine growth. Recently, two distinct TNF receptors (TNF-Rs), TNF-R(p55) and TNF-R(p75), have been identified. In this study, we show that both receptor types may be expressed by AML blasts. It has been investigated whether the different effects of TNF on AML blasts can be explained by differential activation of the distinct TNF-R structures. For this purpose, we used the monoclonal antibodies HTR-1 and HTR-9, specifically recognizing TNF-R(p55), and UTR-1, specific for TNF-R(p75). TNF-(alpha and -beta) mediated synergistic activation with IL-3/GM-CSF, upregulation of IL-3/GM-CSF receptors, inhibition of G-CSF-induced growth, and rapid downmodulation of G-CSF receptors exclusively result from activation of TNF-R(p55). In certain cases in which TNF-alpha, rather than TNF-beta, induces AML growth through an autocrine mechanism, both TNF-R(p55) and (p75) are involved. These data indicate that the variety of TNF responses observed in AML can only be partially explained by differential activation of the TNF-R(p55) and (p75) structures, and that TNF-R(p55) on AML blasts can transduce both positive (synergism with IL-3/GM-CSF) and negative regulatory signals (inhibition of G-CSF-induced proliferation) following TNF activation.
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PMID:Involvement of tumor necrosis factor (TNF) receptors p55 and p75 in TNF responses of acute myeloid leukemia blasts in vitro. 138 4

Disseminated fungal infection not infrequently complicates the course of allogeneic bone marrow transplantation (allo BMT) in severely immunocompromised patients, and the prognosis of BMT patients who develop systemic fungal infection is very poor. We describe a patient who developed disseminated Candida albicans infection with liver abscess after the first allo BMT for acute myelogenous leukemia (FAB M2). The infection was successfully eradicated by the administration of miconazole and amphotericin B. However, 1 year after the first allo BMT, the patient suffered a relapse of acute myelogenous leukemia with fungal liver abscess. A second allo BMT, accelerating granulocyte recovery by recombinant human granulocyte colony-stimulating factor (rhG-CSF), was successfully performed and the fungal liver abscess resolved with a combination therapy of fluconazole and amphotericin B. The patient is alive and free of both leukemia and fungal disease more than 37 months after the first allo BMT and 25 months after the second allo BMT.
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PMID:Successful second allogeneic bone marrow transplantation in a relapsed acute myeloid leukemia patient with fungal liver abscess. 138 22

The ectopic expression of lineage markers on irrelevant cell types may be of importance in the differentiation pathway(s) of these cells. One example, that is the subject of this study, is the presence of the interleukin-4 (IL-4) receptor on the surface of the human HL-60 myeloid leukemia cell line. The presence of such a receptor, that at first seems to be a simple genetic misprogramming, has an unusual biological function: It serves as a bridge to link the B cell growth factor IL-4 in order to transduce a number of differentiation signals in this M2 acute myeloid leukemia (AML) population. Signal transduction is followed by stimulation of RNA synthesis and subsequent induction of differentiation. Daily administration of low IL-4 dose yields proliferative senescent cells that exhibit 66% of growth inhibition in a 5-day tritiated thymidine incorporation assay. These cells clearly exit from the standard M2 morphology and show more mature characteristics as assessed by the Giemsa-Wright staining technique, followed by a 2-fold increase of the monocyte-granulocyte-specific Mac-1 surface antigen. Cellular function is also affected positively since phagocytosis of latex beads increases considerably after IL-4 treatment. Finally, as reported for normal human and murine monocytes and macrophages, the receptor-ligand interaction augments the levels of the class I and class II antigenic determinants by approximately 60%. Our results suggest that ectopic expression of markers may be a "distinct" event required during a short period in the differentiation of certain hemopoietic cells leading to mature and normal phenotypes.
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PMID:The role of IL-4 in human myeloid leukemia: stimulation of RNA synthesis and transduction of differentiation signals through an IL-4 receptor leads to functional and HLA positive HL-60 cells. 147 51

This study aimed to evaluate the effect of melphalan on both terminal divisions and self-renewal capacity of acute myeloblastic leukemia (AML) progenitors (colony-forming units, CFU-L) grown in methylcellulose. Terminal divisions and self-renewal were assayed by primary (PE1) and secondary (PE2) colony formation, respectively. Thirteen cases of AML, were tested. Melphalan induced a negative exponential dose-effect on CFU-L survival. Moreover, melphalan was equally effective in inhibiting CFU-L growth in both PE1 and PE2 assays, with D10 values of 1.53 +/- 0.17 micrograms/ml and 1.59 +/- 0.21 micrograms/ml for PE1 and PE2, respectively (p = 0.48). Cytotoxicity of melphalan on CFU-L did not differ significantly from that observed for normal hemopoietic granulocyte-macrophage colony-forming units, erythroid burst-forming units, and granulocyte-erythroid-macrophage-megakaryocyte progenitors. Mafosfamide-lysine, a stable cyclophosphamide congener, strongly inhibited primary colony formation (PE1) with a D10 value of 14.46 +/- 1.76 micrograms/ml, but was much less efficient in the PE2 assay. Our findings suggest that the self-renewal capacity of AML progenitors can be differentially affected by alkylating agents. Moreover, since it is now considered that chemotherapy should be preferentially directed against the self-renewal of leukemic progenitors, melphalan might offer a greater potential than cyclophosphamide or cyclophosphamide derivatives in the therapy of AML.
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PMID:Effect of melphalan against self-renewal capacity of leukemic progenitors in acute myeloblastic leukemia. 156 57

The availability of an in vitro assay able to detect hematopoietic progenitor cells closely related to those responsible for marrow engraftment following autologous bone marrow transplantation (ABMT) prompted us to establish a procedure aimed at maximally increasing the concentration of the cyclophosphamide derivative mafosfamide used for marrow purging. It, therefore, was the aim of the present study to investigate in a group of patients with acute nonlymphoblastic leukemia (ANLL; n = 19) and acute lymphoblastic leukemia (ALL; n = 19) in complete remission the effect of mafosfamide at the level of adherent blast colony-forming units (blast colony-forming units, CFU-Blast), as well as multipotential (granulocyte erythrocyte macrophage megakaryocyte colony-forming units, CFU-GEMM), erythroid (erythroid burst-forming units, BFU-E), and granulocyte-macrophage (granulocyte-macrophage colony-forming units, CFU-GM) progenitor cells. When nonadherent marrow mononuclear cells (MNCs) were incubated (30 min, 37 degrees C) with increasing doses of mafosfamide (30-120 micrograms/ml), a statistically significant (p less than or equal to 0.0005) dose-dependent suppression of CFU-Blast growth was observed. The mean (+/- 1 standard error of the mean [SEM]) values of 50% inhibition (ID50) of the CFU-Blast growth were not significantly different for ANLL (106 +/- 5) and ALL (107 +/- 5) patients. Analysis of CFU-Blast ID50 distribution demonstrated that ID50 ranged from 100 to 120 micrograms/ml in 17 cases (45%), whereas it ranged from 60 to 100 micrograms/ml in 12 cases and from 120 to 160 micrograms/ml in 9 cases. A statistically significant (p less than or equal to 0.05), dose-dependent suppression of colony growth from multi-potential and lineage-restricted progenitor cells was also observed. However, the value of CFU-Blast ID50 was significantly higher (p less than or equal to 0.05) than CFU-GEMM, BFU-E, and CFU-GM ID50 and ID95 values. In conclusion, our data demonstrate that: 1) the CFU-Blast assay allows to detect on an individual basis the doses of mafosfamide used for marrow purging, and 2) the concentrations of mafosfamide extrapolated by using the CFU-Blast assay are significantly higher than those obtained with the CFU-GM assay. The absence of any detrimental effect on marrow engraftment in vivo supports the safety of the CFU-Blast assay to evaluate the dose of mafosfamide used for marrow purging before ABMT.
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PMID:Differential sensitivity of adherent CFU-blast, CFU-mix, BFU-E, and CFU-GM to mafosfamide: implications for adjusted dose purging in autologous bone marrow transplantation. 156 48

The effects of in vitro pretreatment with benzene metabolites on colony-forming response of murine bone marrow cells stimulated with recombinant granulocyte/macrophage colony-stimulating factor (rGM-CSF) were examined. Pretreatment with hydroquinone (HQ) at concentrations ranging from picomolar to micromolar for 30 min resulted in a 1.5- to 4.6-fold enhancement in colonies formed in response to rGM-CSF that was due to an increase in granulocyte/macrophage colonies. The synergism equaled or exceeded that reported for the effects of interleukin 1, interleukin 3, or interleukin 6 with GM-CSF. Optimal enhancement was obtained with 1 microM HQ and was largely independent of the concentration of rGM-CSF. Pretreatment with other authentic benzene metabolites, phenol and catechol, and the putative metabolite trans, trans-muconaldehyde did not enhance growth factor response. Coadministration of phenol and HQ did not enhance the maximal rGM-CSF response obtained with HQ alone but shifted the optimal concentration to 100 pM. Synergism between HQ and rGM-CSF was observed with nonadherent bone marrow cells and lineage-depleted bone marrow cells, suggesting an intrinsic effect on recruitment of myeloid progenitor cells not normally responsive to rGM-CSF. Alterations in differentiation in a myeloid progenitor cell population may be of relevance in the pathogenesis of acute myelogenous leukemia secondary to drug or chemical exposure.
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PMID:Synergistic action of the benzene metabolite hydroquinone on myelopoietic stimulating activity of granulocyte/macrophage colony-stimulating factor in vitro. 157 Feb 88

We studied the in vitro effects of granulocyte-macrophage colony-stimulating factor (GM-CSF) in 13 patients with acute myeloid leukemia (AML) and one patient with refractory anemia with excess of blasts in transformation using the AML blast (AML colony-forming units, AML-CFU) and mixed (granulocyte erythrocyte macrophage megakaryocyte colony-forming units, CFU-GEMM) colony culture assays. In parallel, these patients received GM-CSF s.c. at 125 micrograms/m2/day, or in escalated doses starting with 10 micrograms/m2/day for a week or until circulating blast counts reached 50 x 10(9)/liter, in an effort to sensitize leukemic blasts to cell-cycle-specific agents. Results of in vivo GM-CSF treatment were correlated with those of in vitro assays. In 9 of 12 patients (75%), GM-CSF treatment increased peripheral blood blast counts (in vivo effect). GM-CSF also stimulated in vitro AML blast colony proliferation in these nine patients and increased the S+G2M phases of the cell cycle in five out of five of these patients' samples. Two of three patients in whom an in vivo response could not be demonstrated also failed to have a detectable in vitro response. These observations suggest that the AML blast colony culture assay may be useful in predicting the response of AML to cytokine therapy. Finally, GM-CSF stimulated granulocyte-macrophage (granulocyte-macrophage colony-forming units, CFU-GM) and erythroid (erythroid burst-forming units, BFU-E) colony proliferation in 14 and 11 patients, respectively, including the 3 individuals who demonstrated no clinical effect on blast counts. It is, therefore, possible that GM-CSF may be used to stimulate proliferation of progenitors that differentiate into mature granulocyte, monocyte-macrophage, and erythroid cells.
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PMID:Comparison of in vivo and in vitro effects of granulocyte-macrophage colony-stimulating factor (GM-CSF) in patients with acute myeloid leukemia. 158 2

Acute myelomonocytic leukemia develops in 10-30% of irradiated (300 rad) SJL/J mice, after a lag period of around one year. Additional treatment with dexamethasone shortly after irradiation increased leukemia incidence up to 50%. Experiments were conducted in order to demonstrate the existence of preleukemic cells in irradiated mice and to explore the possible role of dexamethasone, cyclophosphamide, and different hemopoietic growth factors on their promotion to overt leukemia. Transplantation of bone marrow cells from mice exposed to 300 rad plus dexamethasone into appropriate recipients, performed 4-5 months after leukemogenic treatment, resulted in acute myeloid leukemia (AML) development of donor origin in 70% of the recipients. Transfer of fractionated preleukemic bone marrow showed that the highest AML incidence developed in the recipients of fractions enriched in early hemopoietic precursors. The promoting effect of dexamethasone on preleukemic cells was confirmed by demonstrating its similar coleukemogenic effect whether administered within several hours or 130 days after radiation. Treatment with cyclophosphamide shortly after radiation could not replace the dexamethasone effect but was found to be complementary to the coleukemogenic effect of dexamethasone. Early administration of hemopoietic growth factors (starting 14 days after radiation and dexamethasone) showed that colony-stimulating factor (CSF) 1 increased the AML incidence (75%) and reduced its latency. Treatment with recombinant granulocyte-CSF (rG-CSF) had a reduced effect and recombinant granulocyte-macrophage CSF (rGM-CSF) had no promoting effect. However, administration of different factors several months after the leukemogenic treatment revealed that rGM-CSF increased AML incidence (75%) and shortened its latency, whereas rG-CSF and CSF-1 had no effect. In contrast, the late administration of recombinant interleukin 6 reduced AML incidence significantly (23%). The present results indicate that murine radiation induced AML is a multiphase process involving radiation induced preleukemia that can be promoted by different treatments.
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PMID:Initiation and promotion in radiation-induced myeloid leukemia. 162 87

Mice undergoing an inflammatory reaction, induced by subcutaneous implantation of copper rods, elaborate two kinds of humoral stimulatory factors: the diffusible granulopoietic stimulator (DGS) that enhances diffusion chamber (DC) granulopoiesis, and the serum colony stimulating factor (CSF) that stimulates in vitro granulocyte-monocyte colony growth. We demonstrate here that mice suffering from acute myeloid leukaemia (AML) are unable to augment the production of these humoral stimulatory factors when acute inflammation is induced. Moreover, our results show that increased levels of normal humoral stimulatory factors (DGS and CSF) do not influence the proliferation and/or the differentiation of leukaemic cells implanted in DC.
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PMID:Acute inflammation effects on in vivo granulopoiesis: comparative studies in healthy and leukaemic mice. 162 42


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