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)

Hypoplastic acute leukemia (HAL) is characterized by pancytopenia and by hypocellularity of the bone marrow. The marrow contains equal to or more than 30% myeloblasts. Absence of tissue infiltrates and/or tumor masses is mandatory. Eight patients are described here. They do not fit into the FAB classification for either acute nonlymphocytic leukemia (ANLL) or myelodysplastic syndrome (MDS), except for one patient who subsequently proved to have a chronic myelomonocytic leukemia (CMML). The median age is 65 years. Two patients, including the CMML patient, are alive, 22 and 6 months from diagnosis. Six patients have died. The median survival is 8 months. Normal bone marrow cells cultured either with HAL sera or with HAL peripheral blood mononuclear cells as feeders and exogenous GM-CSF yielded subnormal CFU-GM counts. This might indicate inhibitory activity of HAL serum and defective stimulatory activity of HAL peripheral blood mononuclear cells.
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PMID:Hypoplastic acute leukemia: description of eight cases and search for hematopoietic inhibiting activity. 145 85

In this study, we further established the role of interleukin-1 alpha (IL-1 alpha), interleukin-1 beta, tumor necrosis factor-alpha (TNF-alpha), and interferon-alpha (IFN-alpha) as regulators of proliferation of acute myeloid leukemia (AML) cells. AML cells from 8 of 15 patients incorporated high levels of 3H-thymidine (3H-TdR) in the absence of exogenous growth factors. The spontaneous DNA synthesis could be abrogated with monospecific antibodies directed toward IL-1 alpha, IL-1 beta, or TNF-alpha, as well as with antigranulocyte-macrophage colony-stimulating factor (GM-CSF). Human recombinant GM-CSF reversed the inhibitory action of each of these antibodies and reinduced DNA synthesis in AML cells. Thus, in these cases, constitutively produced IL-1 or TNF-alpha had stimulated the synthesis of GM-CSF, which resulted in GM-CSF-dependent proliferation of AML blasts. Exogenous IL-1 up-regulated the endogenous production of GM-CSF, suggesting a positive regulation of autocrine growth factor production. We also present evidence that TNF-alpha may exert both stimulative as well as inhibitory effects on DNA synthesis in AML cells. The enhancing effect of TNF-alpha was mediated through the induction of GM-CSF production, as stimulation of DNA synthesis in AML blasts could be abrogated with anti-GM-CSF antibody. A concentration-dependent inhibitory effect of TNF-alpha on 3H-TdR incorporation into AML blasts was observed only when these cells were grown in the absence of GM-CSF. Finally, we show that human recombinant IFN-alpha is a potent inhibitor of AML cell proliferation in vitro.
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PMID:Effect of interleukin-1, tumor necrosis factor-alpha, and interferon-alpha on the blast cells of acute myeloblastic leukemia. 150 80

In conclusion, hematopoietic growth factors have been shown to enhance the recovery and function of circulating WBCs after standard-dose cancer therapy or high-dose cancer therapy with ABMT, and preliminary data strongly suggests that these agents may have the ability to restore leukocyte numbers and competence in AIDS, myelodysplastic syndromes, and other marrow failure states. Phase I and II trials of GM-CSF in patients with AIDS, cancer, marrow failure states, and following bone marrow transplantation have been published, and limited phase III randomized trial experiences have been reported as well. Overall, GM-CSF represents a fascinating molecule with which to modulate human hematopoiesis in vivo. The multilineage stimulatory effects of GM-CSF that are evident in vitro have not been striking or consistent in clinical trials. However, the effects of GM-CSF on the production and function of mature neutrophils, monocytes, and eosinophils have been noted in the vast majority of clinical scenarios in which this cytokine has been tested. The clinical benefits of GM-CSF have, to date, only been proven in large-scale randomized studies of recovery from ABMT for lymphoid neoplasms. However, further data regarding the use of GM-CSF in other clinical settings have been generated, and the final results are eagerly anticipated by the oncology community. The beneficial effects of GM-CSF following ABMT consisted not only of a shorter period of absolute neutropenia, but also fewer significant infections, a diminished requirement for intravenous antibiotic administration, and a shorter overall duration of inpatient hospitalization. The use of GM-CSF in clonal disorders of hematopoiesis, such as myelodysplasia or myeloid leukemias, requires caution before such applications can be routinely recommended, and the demonstration of safety in this setting from large randomized trials will be needed. Preliminary data from small randomized trials suggests that the incidence of evolution to leukemia in patients with myelodysplasia and the number of patients with regrowth of leukemia after induction treatment in relapsed patients with AML may not be significantly different than in patients who do not receive GM-CSF. Various neutropenic conditions (eg, idiopathic or congenital) may respond clinically to hematopoietic growth factors such as GM-CSF. Patients treated for 3 to 15 months continue to respond with significantly increased granulocytes and resolution of prior infection. The subcutaneous route of administration is convenient and patients seem to accept it readily. It is difficult to determine the extent to which adjunctive therapy with GM-CSF will be cost effective.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Granulocyte-macrophage colony-stimulating factor (GM-CSF): preclinical and clinical investigations. 150 75

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

These ECOG trials have demonstrated that progressive increments in the intensity of post-remission therapy result in improving long-term, disease-free survival in adults with AML. The median duration of disease-free survival and long-term outcome from different post-remission therapies are summarized in Table 4. [table: see text] Despite the suggestive evidence of the ordered increment in value of intensive consolidation therapy, allogeneic and autologous bone marrow transplantation, it remains to be proved that the differences observed in our preceding studies are statistically significant and clinically meaningful. These remaining questions led to the current ECOG study, EST 3489, a randomized intergroup study conducted with members of the Southwest Oncology Group. The study includes all patients with de novo AML up to age 55; the schema is shown in Figure 3. Induction therapy consists of idarubicin plus cytarabine instead of DAT. A modified short course of this induction therapy is repeated after CR. Patients who have a histocompatible sibling are offered allogeneic bone marrow transplantation. The remaining patients are randomized to receive either autologous bone marrow transplantation or a single course of high-dose cytarabine. Autologous bone marrow transplantation utilizes the previously described high-dose busulfan and cyclophosphamide regimen plus 4-HC purging of the bone marrow. The dosage of cytarabine in the intensive consolidation arm is 3 gm/M2/day IV on days 1-6. The results of this study should determine the relative merits of these different approaches to post-remission therapy. [table: see text] As mentioned earlier, demonstration of improved CR rates is limited by the morbidity and mortality from the myelosuppression that results from induction therapy. This is especially marked for older patients with AML. In patients, ages 55-70 years old, the ECOG is conducting a randomized trial (EST 1490) of conventional induction therapy +/- GM-CSF to determine if accelerated neutrophil recovery can reduce the mortality of induction therapy and thereby increase the remission rate. It may be that the application of GM-CSF and other colony-stimulating factors can increase the CR rate for all patients, increasing the number of patients potentially eligible for cure by post-remission therapy.
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PMID:Escalating the intensity of post-remission therapy improves the outcome in acute myeloid leukemia: the ECOG experience. The Eastern Cooperative Oncology Group. 157 10

In order to further improve the cure rate in AML we investigated the effect of more chemotherapy--in terms of its intensity and its duration--in 2 studies. In our 1981 study patients received TAD 1-2 courses for induction, 1 course for consolidation and randomly no further treatment or monthly myelosuppressive maintenance for 3 years. Evaluating 213 responders remission duration was clearly longer in the maintenance group with 24% CCR after 5 and 10 years. In our 1985 study the same successful strategy was further intensified by a second induction course given regardless of response to the first course to all patients up to 60 years of age while older patients received standard induction as before. This age-adapted concept resulted in a further increase of 5 years CCR in the 461 responders to as much as 34% not achieved for unselected patients in other multicenter trials. 20 patients receiving auto-BMT in first CR show the same relapse free survival as their counterparts receiving chemotherapy according to the 1985 protocol in a matched-pair analysis. We conclude that both very early intensification and prolonged maintenance contribute to a higher cure rate that is not further improved even by a maximum intensity short-term treatment. The limits of chemotherapy in AML may be overcome by modulating its myelotoxicity and antileukemic potency using GM-CSF as shown in 2 studies of our group.
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PMID:Longterm effects of prolonged maintenance and of very early intensification chemotherapy in AML: data from AMLCG. 157 46

We have examined the effect of a combined 24 h exposure to cytosine arabinoside (ara-C) and the protein kinase C activator bryostatin 1, either alone or in conjunction with recombinant granulocyte-macrophage colony-stimulating factor (rGM-CSF), on the clonogenic growth of 14 primary samples from acute myelogenous leukemia (AML) patients, as well as normal human committed and early hematopoietic progenitors. Incubation of blasts with 1 microM ara-C and 12.5 nM bryostatin 1(+/- 1.25 ng/ml rGM-CSF) resulted in a heterogeneous pattern of inhibitory effects toward primary leukemic colonies, ranging from 32-98%, and subadditive to synergistic drug interactions. However, exposure of blasts to ara-C and bryostatin 1, either with or without rGM-CSF, eliminated leukemic cell self-renewal in 80-93% of samples, and very substantially reduced growth in the remainder. Exposure of normal human bone marrow mononuclear cells to identical concentrations of ara-C and byostatin 1 permitted the survival of 23% of committed myeloid progenitors (granulocyte-macrophage colony-forming units), and greater than 50% when rGM-CSF was included. Finally, exposure of bone marrow populations highly enriched for progenitor cells (CD34+, DR-, CD71-) to ara-C and bryostatin 1 +/- rGM-CSF for 24 h led to minimal reductions (e.g. 10-15%) in the survival of early hematopoietic progenitors (high proliferative potential colony-forming cells). Together, these findings indicate that combined exposure in vitro to ara-C and bryostatin 1, both with and without rGM-CSF, effectively inhibits the growth of leukemic cells with self-renewal capacity, while sparing a significant fraction of normal committed and primitive hematopoietic progenitors.
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PMID:Effect of a combined exposure to cytosine arabinoside, bryostatin 1, and recombinant granulocyte-macrophage colony-stimulating factor on the clonogenic growth in vitro of normal and leukemic human hematopoietic progenitor cells. 159 8

Myeloid leukemia development requires the acquisition by a cell of two abnormalities: an abnormal capacity for self-replication; and a capacity for autocrine stimulation, usually involving the known growth factors for granulocyte-macrophage cells. Curiously, in human leukemia, this does not usually result in autonomous growth when assessed in clonal in vitro cultures. Depending on gene programming, in particular in human or murine myeloid leukemias, the hemopoietic growth factors can also suppress the leukemic population by inhibiting the capacity of the leukemic stem cells for self-generation. The regulator showing the highest suppressive activity varies from leukemia to leukemia, with G-CSF. GM-CSF, IL-6, or leukemia-inhibitory factor (LIF) all having high activity on appropriate target cells. Combinations of these regulators are more effective than single agents alone. Analyses of human HL60, U937 and murine M1 leukemic models indicate that the development of morphological maturation in the leukemic cells is not a necessary feature of stem-cell suppression. LIF has an anomalous action on stem-cell self-generation, being highly effective in the suppression of certain myeloid leukemic cell lines, but being necessary to maintain self-generation in normal embryonic cells. This suggests the existence of a common control medium governing self-generation decisions in cells of different lineages, but that the outcome of the decision is determined by the differentiation program operating in different cells. The colony-stimulating factors are being used in combination with chemotherapy in the treatment of patients with acute myeloid leukemia, but the above principles require caution in certain situations.
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PMID:Role of hemopoietic growth factors in the development and suppression of myeloid leukemia. 160 21

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.
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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.
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PMID:Response of leukemic cells to the sequential combination of GM-CSF and G-CSF. 168 53


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