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)

The lymphokine interleukin-3 (IL-3) promotes the growth and survival of immature hematopoietic cells. Previous studies have shown that IL-3 induces rapid increases in protein-tyrosine kinase (PTK) activity in IL-3--dependent cells. Unlike some other hematopoietic growth factor receptors (eg, c-fms and c-kit), however, the known subunits of the IL-3 receptor (IL-3R) lack intrinsic kinase activity. Recently, it was reported that the IL-2R (whose p75 beta-subunit shares sequence homology with a known murine IL-3R subunit and a common beta-subunit of the human IL-3R and granulocyte-macrophage colony-stimulating factor [GM-CSF] receptors) can physically associate with and regulate the activity of the SRC-family PTK, p56-LCK. Because most IL-3--dependent cells contain p53/56-LYN, but not p56-LCK, we explored the effects of IL-3 on the activities of LYN and other SRC-like PTKs in two human leukemic cell lines, AML-193 and TALL-101, which are phenotypically myeloid, and whose in vitro growth is dependent on IL-3. These cells expressed four of the eight known SRC-family proto-oncogenes: lyn, fyn, yes, and hck. When these factor-dependent leukemic cell lines were deprived of lymphokine to achieve cellular quiescence and then restimulated with IL-3, rapid increases (detectable within 1 minute and maximal by 10 minutes) were observed in the activity of the p53/56-LYN kinase, as assessed by in vitro kinase assays. In contrast, no alteration in the activities of other SRC-family PTKs present in these cells was detected after restimulation with IL-3 under the same conditions. This effect of IL-3 reflected an increase in the specific activity of the LYN kinase, because levels of the 53-Kd and 56-Kd LYN proteins were unaltered by IL-3 stimulation, as assessed by immunoblotting. Furthermore, the magnitude of these inducible increases in LYN kinase activity was dependent on the concentration of IL-3, and correlated with IL-3--induced proliferation. The IL-3--induced upregulation of LYN kinase activity may be mediated by the 120-Kd common subunit of the human IL-3 and GM-CSF receptors, because GM-CSF also stimulated marked increases in the activity of the LYN kinase, whereas granulocyte-CSF (G-CSF) did not, despite inducing cellular proliferation. These observations provide the first example of an IL-3--regulable PTK, and strongly suggest that the p53/56-LYN kinase participates in early IL-3--initiated signalling events, at least in some human leukemic cell lines.
 ...
PMID:Interleukin-3 regulates the activity of the LYN protein-tyrosine kinase in myeloid-committed leukemic cell lines. 163 19

We designed two experiments using delayed stimulation by granulocyte/macrophage colony-stimulating factor (GM-CSF) or granulocyte colony-stimulating factor (G-CSF) with colony-type analysis in order to elucidate the characteristics of factor-dependent proliferation and differentiation of leukemic progenitor cells. Eight patients with acute myelogenous leukemia showing non-autonomous colony growth were selected. Three of the six cases showed that delayed addition of G-CSF to agar culture initiated by GM-CSF had no influence on the type and number of colonies; whereas, delayed addition of GM-CSF to G-CSF resulted in additional GM colonies. These findings were the same for normal bone marrow progenitors. In two cases, granulocytic colonies markedly increased with delayed addition of G-CSF to GM-CSF. Synergism occurred in one case where GM-CSF was used first. In the next experiment, regardless of whether CSF was used during the 48 hour preincubation, subsequent colony types were affected by the CSF used in agar culture. But colony numbers increased 1.5 fold in two of six cases by preincubation with GM-CSF, and 1.2 to 1.7 fold in all normal cases by preincubation with G-CSF. These results suggest that although there is a great heterogeneity in the response to CSF, some leukemic progenitors act like normal progenitors.
 ...
PMID:Response of leukemic cells to the sequential combination of GM-CSF and G-CSF. 168 53

In this study we demonstrate that tumor necrosis factors (TNF alpha and TNF beta) are potent modulators of the in vitro proliferation of human AML cells. Blast cells from 11 cases of acute myeloblastic leukemia (AML) were incubated with recombinant TNF alpha or TNF beta in serum-free 3H-TdR uptake and colony culture systems in the presence or absence of recombinant interleukin-3 (IL-3), granulocyte macrophage colony-stimulating factor (GM-CSF), G-CSF, or M-CSF. Depending on the supplemented CSF, TNF could upregulate or suppress AML blast proliferation. Enhancement of AML growth by TNF was observed in the presence of IL-3 (in 9 of 11 cases in 3H-TdR assay; 6 of 9 cases in colony assay) and GM-CSF (in 8 of 11 cases in 3H-TdR assay; 4 of 9 cases in colony assay). In certain cases in which IL-3 or GM-CSF alone was unable to induce proliferative responses of AML cells, the simultaneous addition of TNF elicited colony growth and DNA synthesis suggesting a synergistic action between TNF and IL-3 or GM-CSF. In contrast, TNF suppressed G-CSF-induced growth (9 of 10 cases in 3H-TdR assay; 5 of 6 cases in colony assay). TNF could also stimulate DNA synthesis (in 2 of 11 cases) or colony formation (in 2 of 9 cases) in AML cultures without the addition of other growth factors. Experiments with neutralizing antibodies and specific radioimmunoassays for individual CSFs showed that the synergistic and antagonistic effects of TNF on AML growth could not be attributed to a release of one of these CSFs by the AML cells. The opposing consequence of exposure of AML blasts to TNF are of interest in view of our understanding of the pathophysiology of AML growth and the in vivo application of recombinant cytokines in AML patients.
 ...
PMID:Modulation of colony stimulating factor-(CSF) dependent growth of acute myeloid leukemia by tumor necrosis factor. 168 38

One proposed therapeutic application of granulocyte colony-stimulating factor (G-CSF) is in differentiation induction therapy of myelodysplastic states (MDS) or acute myeloid leukemia (AML). G-CSF however has a substantial growth including effect which limits its potential as a differentiation inducing agent. We have therefore made a systematic search for agents which might restrain the proliferative effects of G-CSF whilst retaining the differentiation stimulus. Of all the agents we have tested on human bone marrow progenitor cells: (6-thioguanine, all-trans retinoic acid, vincristine, recombinant human alpha-2b and gamma-interferon) only the latter abolished the stimulation of cell growth and retained, or possibly increased, the differentiation effect of G-CSF. The antiproliferative drugs 6-thioguanine and vincristine both antagonized the neutrophil-granulocyte differentiation inducing action of G-CSF. Retinoic acid and alpha-2b interferon both had weak effects on proliferation and failed to enhance differentiation. These results suggest that it may be possible, by combining G-CSF with a suitable second agent, to utilize its substantial differentiation inducing effect without incurring the potentially hazardous effects of increased leukemic cell growth.
 ...
PMID:Dissociation of the proliferation and differentiation stimuli of granulocyte colony-stimulating factor (G-CSF). 169 Mar 19

The in vitro growth response of bone marrow and blood cells to granulocyte/macrophage colony-stimulating factor (GM-CSF) and granulocyte colony-stimulating factor (G-CSF) was studied in 18 acute myeloid leukemia (AML) patients using semisolid and suspension cultures. In 80% of the cases growth of leukemic progenitor cells was stimulated by GM-CSF and/or G-CSF, as judged by colony or cluster formation. In acute promyelocytic leukemia [t(15;17)], G-CSF stimulated and maintained the leukemic progenitors only transiently but fully stimulated the residual normal granulocyte/macrophage colony-forming units (CFU-GM). In some cases of M2 and M4 leukemia, G-CSF enhanced markedly the production of mature but cytochemically abnormal neutrophils. In some cases of M1 leukemia, neither CSF stimulated leukemic progenitors but instead stimulated only residual normal granulopoiesis. Spontaneous colony formation was observed in 20% of cases and was correlated with high-grade leukemic growth in vivo and a poor response to chemotherapy. The differing effects of the CSFs upon leukemic cells and residual normal granulopoiesis may have some implications for the clinical use of GM-CSF and G-CSF to overcome infectious complications.
 ...
PMID:In vitro growth response to G-CSF and GM-CSF by bone marrow cells of patients with acute myeloid leukemia. 169 Aug 27

The cytokine interleukin-1 (IL-1) plays a role in the regulation of normal as well as leukemic hematopoiesis. In acute myeloid leukemia (AML), IL-1 induces autocrine granulocyte/macrophage colony-stimulating factor (GM-CSF) and tumor necrosis factor (TNF) production, and these factors may then synergistically induce proliferation in AML blast cells. In this report, we show that IL-1 stimulates DNA synthesis of highly enriched normal bone marrow blast cells (CD34 positive, adherent cell depleted, CD3/CD14/CD15 negative). The stimulative effect of IL-1 can be blocked with neutralizing anti-TNF alpha and anti-GM-CSF antibodies and, most efficiently, by the combination of anti-TNF alpha and anti-GM-CSF, but not with anti-G-CSF antibody, suggesting that IL-1-induced proliferation was initiated through TNF and GM-CSF release. Concentrations of TNF and GM-CSF increased in the culture medium of normal bone marrow blast cells after IL-1 induction. Of the IL-1-induced cells, 12% were positive for GM-CSF mRNA by in situ hybridization, as opposed to 6% of non-induced cells. Thus, in addition to its effect on leukemic blast cells, IL-1 also acts on normal marrow blast cells. We propose a scheme where IL-1 stimulation of normal bone marrow blast cells leads to the induction of TNF alpha and GM-CSF, which in association stimulate DNA synthesis efficiently according to a paracrine or autocrine mechanism within the marrow blast cell compartment.
 ...
PMID:Interleukin-1 alpha also induces granulocyte-macrophage colony-stimulating factor in immature normal bone marrow cells. 169 8

Based on pre-clinical 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 hormones have been used to treat cytopenic patients with preleukemia [i.e., myelodysplastic syndromes (MDS)]. To date, five studies have been reported using GM-CSF short-term (generally 7-14 days, x 1-5 courses). Thirty-eight of 45 treated patients had improvements in neutrophil counts, 14 had increased reticulocyte counts with three of these individuals having decreased RBC transfusion requirements, and eight had transient increases in platelets. In 12 patients an increase in marrow and/or peripheral blood blasts was noted. Seven patients progressed to acute myeloid leukemia (AML), particularly patients with greater than 15% marrow blasts. In a longer term study, five patients received GM-CSF for 2 to 9 weeks, although only one individual maintained increased neutrophil counts, one developed antibodies to GM-CSF and one evolved into AML. Eighteen patients have been treated for 2 months 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, no substantial changes in platelet counts were noted. Eleven patients have received maintenance therapy with G-CSF for 6-16 months, ten had persistent increases in neutrophil counts with enhanced marrow myeloid maturation and five had increased reticulocytes. Decreased infectious episodes were notedat times of neutrophil improvements. Four of the 18 individuals have subsequently developed AML after 6-16 months.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Effects of CSFs in preleukemia. 169 91

Background. Although colony-stimulating factors have been shown to accelerate recovery from severe neutropenia after intensive chemotherapy or bone marrow transplantation, their use in acute leukemia has been controversial because in vitro they stimulate leukemic colonies as well as normal granulocyte colonies. Methods. We conducted a prospective, randomized, controlled study to determine the safety and efficacy of recombinant human granulocyte colony-stimulating factor (CSF) after a standard course of intensive therapy in 108 patients with relapsed or refractory acute leukemia (67 with acute myelogenous leukemia, 30 with acute lymphocytic leukemia, 9 in blast crisis from chronic myelogenous leukemia, and 2 with acute leukemia arising from myelodysplastic syndromes). Treatment with granulocyte CSF (200 micrograms per square meter of body-surface area per day in a 30-minute infusion) was begun two days after the end of the chemotherapy and continued until the neutrophil count rose above 1500 per cubic millimeter. Results. Treatment with granulocyte CSF accelerated the recovery of neutrophils significantly (P less than 0.01), shortening it by about a week, but it had no effect on platelet recovery. Although the incidence of febrile episodes was almost the same, documented infections were significantly less frequent in the group treated with granulocyte CSF (P = 0.028). There was no evidence that granulocyte CSF accelerated the regrowth of leukemic cells. Fifty percent of 48 patients in the CSF group who could be evaluated and 36 percent of 50 controls had complete remission. The rate of relapse was almost the same in the two groups. Conclusions. It appears that recombinant human granulocyte CSF is safe in acute leukemia, accelerating neutrophil recovery and thereby reducing the incidence of documented infection without affecting the regrowth of leukemic cells. It should be used with caution, however, pending further confirmation of these early results.
 ...
PMID:Effect of granulocyte colony-stimulating factor after intensive induction therapy in relapsed or refractory acute leukemia. 169 46

We investigated functional interactions between granulocyte-monocyte-colony-stimulating factor (GM-CSF) and the insulin family hormones using the GM-CSF- and insulin-dependent human acute myeloid leukemia cell line AML-193. Recombinant human GM-CSF and insulin enhanced AML-193 cell proliferation 3- and 5-fold, respectively, and showed a synergistic 10-fold increase when added in combination. Insulin-like growth factors I and II (IGFI and IGFII) increased AML-193 cell proliferation 4-fold and 2-fold, respectively, and also demonstrated synergy when combined with GM-CSF. Blocking experiments with monoclonal antibodies against the insulin and IGFI receptors indicated that the proliferative effects of insulin and IGFI were mediated through both their homologous and heterologous receptors. Pertussis toxin and cholera toxin, which ADP ribosylate GTP-binding proteins (G proteins), and the cyclic AMP analogue, dibutyryl cyclic AMP, decreased the proliferation induced by GM-CSF or insulin. Specific receptor binding of 125I-insulin, -IGFI, and -GM-CSF to AML-193 cells was demonstrated and not affected by preincubation with pertussis toxin or cholera toxin. Radiolabeled GM-CSF, insulin, and IGFI did not cross-compete with the heterologous ligands for receptor binding. These studies demonstrate (a) association between receptor binding and proliferative effects of GM-CSF and the insulin family hormones, (b) involvement of the G proteins in signal transduction provoked by these hormones which occurs at a postreceptor-binding level, and (c) synergistic mitogenic interactions between GM-CSF and the insulin family hormones, suggesting that their receptors are linked to divergent signaling mechanisms in addition to sharing G protein-coupled pathways.
 ...
PMID:Functional interactions between colony-stimulating factors and the insulin family hormones for human myeloid leukemic cells. 169 37

In vitro proliferation of leukemic cells purified from 10 cases of acute myeloblastic leukemia (AML) was analyzed in basal conditions or in the presence of exogenous recombinant (r) Interleukin (IL) 1. In parallel, blasts from 5 of these patients were studied for granulocyte-macrophage colony-stimulating factor (GM-CSF) or granulocyte-CSF (G-CSF) mRNA. IL-1 augmented the spontaneous AML cell proliferation in all cases and induced de novo expression or increased amounts of GM-CSF and/or G-CSF transcripts in 4 of the 5 cases evaluated. IL-1-induced AML cell proliferation was modulated by neutralizing anti-GM-CSF or anti-G-CSF antibodies in those cases in which CSF mRNAs were induced or increased by exogenous cytokine. In the same cases, biosynthetic labelling and immunoprecipitation studies using monospecific anti-GM-CSF antibodies showed that IL-1 also increased the levels of GM-CSF protein synthesis. Addition of neutralizing anti-IL-1 antibodies to AML cell cultures completely abolished ongoing GM-CSF synthesis, suggesting that endogenous IL-1 is needed to maintain autocrine production of CSFs. The effects of rIL-2 were investigated in a larger series of 21 patients. The cytokine reduced spontaneous AML cell proliferation in 8 cases. It caused complete disappearance of GM-CSF mRNA in 1 case, and marked reduction of G-CSF mRNA in 2 cases. Increased AML cell proliferation was observed in 2 of 21 cases. These findings suggest that expression of CSF genes and cell proliferation in AML are under the control of different cytokines acting in autocrine or paracrine fashion.
 ...
PMID:Interleukin-1 and interleukin-2 control granulocyte- and granulocyte-macrophage colony-stimulating factor gene expression and cell proliferation in cultured acute myeloblastic leukemia. 169 3


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>