Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0023418 (leukemia)
 93,477 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effects of the protein kinase C activator bryostatin 1, either with or without recombinant granulocyte-macrophage colony stimulating factor (rGM-CSF) were examined with respect to the in vitro metabolism of ara-C in leukaemic myeloblasts obtained from 10 patients with acute myelogenous leukaemia (AML). Coincubation of cells with 12.5 x 10(-9) M bryostatin 1 and 10(-5) M ara-C for 4 h resulted in a significant increase in ara-CTP formation (compared to controls) in 6/10 specimens (mean increase 106%; range 38-255%), and no change in the remainder. In contrast, coincubation of cells with 1.25 ng/ml rGM-CSF resulted in a significant increase in only one specimen, and decreases in two. Bryostatin 1 also significantly increased ara-C DNA incorporation in 6/9 evaluable samples, including two which did not display an increase in ara-CTP formation. Coincubation of cells with both bryostatin 1 and rGM-CSF did not lead to a further increase in ara-CTP formation or ara-C DNA incorporation compared to values obtained with either agent alone. Finally, exposure of blasts to bryostatin 1 for 24 h before ara-C led to an increase in ara-CTP formation in 3/8 additional specimens, and a decrease in one sample displaying evidence of bryostatin 1-induced macrophage differentiation. Incubation of cells with both rGM-CSF and bryostatin 1 for this period resulted in ara-CTP levels equivalent to those obtained with bryostatin 1 alone. These studies indicate that while bryostatin 1 exerts a heterogeneous effect on ara-C metabolism in leukaemic myeloblasts, it is capable of potentiating ara-C phosphorylation in a subset of patient samples, including some that do not exhibit an increase in response to rGM-CSF. They also raise the possibility that bryostatin 1-induced potentiation of ara-C metabolism in some leukaemic cells may contribute, at least in part, to the antileukaemic efficacy of this drug combination.
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PMID:Effects of bryostatin 1 and rGM-CSF on the metabolism of 1-beta-D-arabinofuranosylcytosine in human leukaemic myeloblasts. 148 32

Symptomatic patients with myelodysplastic syndromes (MDS) and 10-30% blasts in the bone marrow were treated with low-dose AraC (2 x 10 mg/m2 subcutaneously (sc) days 1-14) and GM-CSF (fully glycosylated, Sandoz/Schering-Plough, 2 x 150 micrograms protein/day sc) given either subsequently (days 15-21) or simultaneously (days 8-14 and one week rest). Evaluations were carried out after three courses (nine weeks); responding patients could be continued for two further cycles. Eighty-two patients with refractory anaemia and excess of blasts (RAEB), with (RAEBt) or without transformation, were evaluable: 45 RAEB and 37 RAEBt, mean age 64 years (range 17-80 years). A complete remission was achieved in 14 cases (17%), 11 had a good response (13%), and 12 a partial response (15%). Stable disease was found in 21 cases (26%). There were 12 cases of toxic death (15%), progression was noted in eight patients (10%), and death due to disease in three (4%). No difference existed between the two treatment arms with respect to response. Major adverse events during treatment were haemorrhage (25%), infections (23%), and fever with GM-CSF (21%). GM-CSF did not induce leukaemia nor contribute to haemorrhage induced by AraC, but gave rise to an overall response rate of 46% which is high and relatively durable as compared to other treatments in this disease.
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PMID:Treatment of myelodysplastic syndromes (MDS) and high leukaemic risk with low-dose cytosine arabinoside (LD-AraC) plus granulocyte-macrophage colony-stimulating factor (rh GM-CSF). The EORTC Leukaemia Group. 149 35

Our studies on the susceptibility of fresh noncultured leukemia cells to interleukin-2 (IL-2)-induced lymphokine-activated killer (LAK) cells have shown that about two thirds of the leukemias are susceptible to the LAK-cell-mediated cytolysis. Analysis of 214 acute leukemias revealed considerable variation in the degree of cytotoxicity achieved. Cytolysis was substantially lower in fresh noncultured acute leukemia samples than in K562 and Daudi cell lines (mean Cr-release 21.0 +/- 16.0% versus 69.2 +/- 6.6% and 70.8 +/- 7.9%). Augmentation of susceptibility to LAK-cell lysis is desirable in connection with therapeutic application of IL-2-induced effector mechanisms. We observed a relationship between the LAK-cell susceptibility of leukemia cells and their spontaneous proliferation rate, which is significantly higher in LAK-cell-sensitive than in LAK-cell-resistant leukemias. It was therefore considered useful to examine the possibility of augmenting LAK-cell sensitivity by proliferation induction. These studies demonstrate that incubation of blast cells from acute myeloid leukemia (AML) and chronic myelogenous leukemia in myeloid blast crisis (CML-BC) with recombinant granulocyte-macrophage colony stimulating factor (GM-CSF) significantly augments LAK-cell susceptibility and that this is associated with an increased cell proliferation.
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PMID:GM-CSF-mediated proliferation induction improves the susceptibility of leukemia cells to lymphokine-activated killer cells. 149 16

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

Second transplants need to be considered in two clinical situations after marrow transplantation. Firstly, failure of sustained engraftment; secondly, recurrence of the underlying malignancy. In patients with failure of sustained engraftment a trial of recombinant human GM-CSF is indicated first with a chance of improving blood counts in a significant proportion of patients. If this is unsuccessful a second transplant utilizing a preparative regime aimed primarily at further minimizing host immune competence such as a combination of antithymocyte globulin (ATG) and cyclophosphamide or ATG alone followed by a T-replete marrow infusion should be employed. A second marrow transplant can also be utilized for recurrence of the underlying haematological malignancy after first transplant. However, several large multi-institutional studies have now shown a striking difference in the long-term leukemia-free survival rate between those relapsing early (for example, less than six months) after the first transplant compared to those relapsing later after the first transplant. Leukemia-free survival post second transplant for those relapsing within six months of first transplant is less than 10%, whereas for those relapsing greater than six months from first transplant it is approximately 30%. Transplant-related mortality, particularly from complications influenced by chemotherapy, such as interstitial pneumonitis and hepatic veno-occlusive disease, are more common after second than after first transplant.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Who should get a second marrow transplant? 152 Oct 96

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.
Leukemia 1992
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.
Leukemia 1992
PMID:Longterm effects of prolonged maintenance and of very early intensification chemotherapy in AML: data from AMLCG. 157 46

We have recently established ME-1, a human myelomonocytic leukaemia cell line derived from acute myelomonocytic leukaemia with eosinophilia (M4E0). When ME-1 cells were cultured in serum-free medium, they stopped proliferating and began to differentiate morphologically, functionally and phenotypically to mature granulocyte-like cells. The protein kinase inhibitor, 1-(5-isoquinolinyl-sulphonyl)-2-methylpiperazine (H-7) enhanced this differentiation dose-dependently. Upon addition of fetal calf serum (FCS) to the serum-free medium, the differentiation of ME-1 cells into granulocyte-like cells was inhibited and they resumed cell growth. We have recently reported that the differentiation of ME-1 cells into macrophage-like cells induced by IL-3 and GM-CSF involved the activation of protein kinase C. The present results indicate that ME-1 is a bipotential cell line that can differentiate into granulocyte-like cells or macrophage-like cells, and that protein kinase C is closely related to each form of differentiation.
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PMID:Granulocytic differentiation of the human myelomonocytic leukaemia cell line ME-1 in serum-free culture. 158 Dec 9

To assess the effects of GM-CSF in patients with myelodysplasia, a total of 101 patients with refractory anemia (RA), RA with ringed sideroblasts (RARS), and RA with an excess of blasts provided that the percentage of blasts in the bone marrow did not exceed 10% (RAEB) were enrolled in the EORTC Leukemia Cooperative Group study 06885. They were randomized to receive two daily subcutaneous injections of rhGM-CSF (mammalian, glycosylated, Sandoz/Schering-Plough) at a daily dose of either 108 micrograms glycoprotein (group I) or 216 micrograms glycoprotein (group II) for 8 weeks. Response was defined as an increase in Hb (greater than 2.5 g%), neutrophil count (more than 100%), or platelet count (more than 100%) without progression of the disease. After exclusion of 19 patients who did not meet the entry criteria, 82 were evaluated. Fifty-four patients (66%) responded (27 of 42 patients in group I and 27 of 40 in group II). Progressive disease was seen in two patients of group I and in four of group II. Two of the latter developed leukemia. All responses were reflected in the granulocytic series. In two patients platelet numbers also increased. Cytogenetic analysis, successfully performed in 43 cases, showed that 14 of 16 patients with normal karyotypes responded, compared with 14 of 27 patients with abnormal karyotypes (p = 0.008). In some cases GM-CSF was reduced in dose or discontinued prematurely due to side effects so that only 35% of all evaluable patients finished 8 weeks of treatment without a change of dose.
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PMID:A randomized phase-I/II multicenter study of recombinant human granulocyte-macrophage colony-stimulating factor (GM-CSF) therapy for patients with myelodysplastic syndromes and a relatively low risk of acute leukemia. EORTC Leukemia Cooperative Group. 158 5

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.
Leukemia 1992
PMID:Role of hemopoietic growth factors in the development and suppression of myeloid leukemia. 160 21


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