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Query: UMLS:C0023467 (
acute myeloid leukemia
)
35,200
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Recombinant human (rh) interleukin-6 (IL-6), in a dose range of 1 to 10 U/mL, was able to induce a low number of neutrophilic-granulocytic colonies in a CFU-GM clonogenic assay, using T cells and adherent cells, depleted low density marrow cells. A synergistic increase in the number of granulocytic colonies was observed when rhGM-CSF at suboptimal doses and IL-6 at effective doses were both present in the assay; the increase was only additive when either rhIL-1 alpha or rhIL-3 was used together with IL-6. To determine whether the increase in colony number reflects the interactions of these factors on the same hematopoietic progenitor target cells or, instead, represents activation of accessory cells, we analyzed the effect of IL-6 on the proliferation and differentiation of three growth factor-dependent leukemic cell lines that respond with continuous proliferation to the presence of
GM-CSF
and IL-3 in culture. One of the three cell lines (
AML
-193) showed limited proliferation in the presence of IL-6 followed by terminal differentiation after 14 days into basophilic-granulocytic-like cells. A synergistic proliferative response was observed on the same cells treated with both
GM-CSF
and IL-6. These data support the hypothesis that IL-6 may have a direct effect on myeloid hematopoietic progenitor cells, and that
GM-CSF
interacts synergistically with IL-6 by acting on the same target cells.
...
PMID:Human interleukin-6 supports granulocytic differentiation of hematopoietic progenitor cells and acts synergistically with GM-CSF. 264 83
The abilities of human recombinant IL-3,
GM-CSF
, G-CSF, M-CSF and Epo to induce maturation in human
AML
cells in vitro were investigated using cell specimens from 25
AML
patients. The experiments were carried out under exactly defined serum-free culture conditions. In the absence of CSFs, monocytic and/or granulocytic maturation was detected in 14/25 cases. IL-3,
GM-CSF
, G-CSF and M-CSF elevated the proportions of monocyte/macrophages in 3/25, 2/25, 1/25 and 6/25 cases respectively, and increased the percentages of mature granulocytes in 2/25, 1/25, 1/25 and 0/25 cases, and if so only to a limited extent (values below 50%). The 3H-thymidine (3H-TdR) uptake studies revealed that IL-3,
GM-CSF
, G-CSF and M-CSF were efficient stimulators of DNA synthesis of
AML
cells in 19, 15, 13 and four of those cases, respectively. Thus, although the cells in most cases responded to CSFs by activation of DNA synthesis, they were unable to give rise to terminally differentiated stages. Provision of CSFs in combination was more frequently effective in enhancing maturation and also increased the magnitude of maturation response. Monocytic versus granulocytic maturation of
AML
cells after culture did not correlate with the FAB cytology nor with the type of CSF presented; but generally granulocytic maturation was an infrequent phenomenon. Epo stimulated erythroid differentiation and DNA synthesis only in the case of erythroleukaemia, but it had no effect on the cells of 10 other
AML
cases. Extrapolation of these in vitro findings would suggest that CSFs would have a limited therapeutic utility to induce
AML
cell maturation in vivo and that hazards of stimulating blast cell proliferation with these factors may be anticipated.
...
PMID:Maturation of human acute myeloid leukaemia in vitro: the response to five recombinant haematopoietic factors in a serum-free system. 264 40
The toxicity, pharmacokinetics, and hematologic effects of granulocyte-macrophage colony-stimulating (
GM-CSF
) were studied in a phase I/II trial of 16 patients with myelodysplastic syndrome (MDS). The
GM-CSF
was administered subcutaneously (SC) daily so as to achieve prolonged blood levels and to establish an outpatient treatment regimen. Four dose levels were administered for ten days: 0.3 microgram/kg/d (three patients), 1.0 microgram/kg/d (three), 3.0 micrograms/kg/d (four), and 10.0 micrograms/kg/d (six). The most common toxicities were fever and a flu-like syndrome, which were dose-dependent. The maximum-tolerated dose was 10.0 micrograms/kg/d, which induced severe rigors (two patients), fever greater than 40 degrees C (one), severe bronchospasm (one), and WBC 60,000 (one). In one patient, refractory anemia with excess blasts in transformation (RAEB-T) progressed to
acute nonlymphocytic leukemia
after two doses of
GM-CSF
, and the patient died of leukemia that did not respond to chemotherapy. After doses of 3.0 and 10.0 micrograms/kg, serum
GM-CSF
levels peaked at 3.8 to 6.3 hours, and persisted for 14 and 24 hours, respectively. Circulating granulocytes (neutrophils and bands) increased in a dose-dependent manner, as 11 of 13 patients who received greater than or equal to 1.0 microgram/kg/d responded with a two- to 194-fold increase. Although the neutrophils usually returned to pretreatment levels shortly after stopping
GM-CSF
, two patients continue to exhibit an elevation of neutrophils for 6 months. Dose-related increases in circulating monocytes and eosinophils were also noted. Transient increases in platelet and reticulocyte counts were observed in two and three patients, respectively. Five of the 16 patients later received maintenance
GM-CSF
at 3 micrograms/kg/d for 2 to 9 weeks. All showed a dramatic increase in neutrophils after 2 weeks. Thereafter, despite continued therapy, the neutrophil count in four patients declined markedly. In conclusion,
GM-CSF
is well tolerated by the SC route and induces striking, but usually temporary, improvement in the neutropenia of MDS. Larger prospective phase III trials will determine the duration of hematologic responses and the impact on infection, morbidity, and mortality.
...
PMID:Subcutaneous granulocyte-macrophage colony-stimulating factor in patients with myelodysplastic syndrome: toxicity, pharmacokinetics, and hematological effects. 265 78
GM-CSF
was used to overcome fatal myelosuppression after cytotoxic chemotherapy. Two different application modalities were compared: a continuous 24 h infusion was more effective compared to a 30 min short term infusion. Using the former modality at a dose of 10 micrograms/kg/d for five days very impressive responses were observed. No major side effects did occur. The first 13 patients treated in this way included 8
AML
cases. Only one of these latter patients had a leukemia relapse. However, in this patient the immediate
GM-CSF
response was clearly separated from the relapse occurring later in the observation period. Thus, the preliminary results of the present paper suggest that
GM-CSF
besides of being very efficient in accelerating granulocyte recovery does not stimulate the growth of
AML
blasts in vivo in patients with only minimal residual disease.
...
PMID:GM-CSF treatment in aplasia after cytotoxic therapy. 265 87
TNF-alpha has been shown to antagonize the proliferative effects of growth factors present in crude conditioned media from PHA-stimulated leukocytes or cell lines on the clonogenic cells of
acute myeloblastic leukemia
(
AML
) (19,21). In the present study, we investigated the responses of
AML
blasts to TNF-alpha in the presence of defined growth factors (recombinant granulocyte/macrophage-CSF [rGM-CSF], recombinant granulocyte-CSF [rG-CSF], rIL-3, and rIL-1) and under conditions described for autocrine stimulation (32). While TNF-alpha antagonized the stimulatory effects of G-CSF and IL-3 on blast progenitors, TNF-alpha did not affect blast colony formation in the presence of IL-1. Unexpectedly, TNF-alpha significantly enhanced blast proliferation in the presence of
GM-CSF
. Further, TNF-alpha also acted synergistically with an endogenous source of growth stimulatory signal to promote proliferation of blast clonogenic cells. Thus, on human leukemic cells, TNF-alpha appears to be a molecule that is at least bifunctional, having the ability to either support or inhibit cell proliferation, depending on the other growth factors present. It is postulated that the proliferative response of blast progenitors to TNF-alpha under conditions that favor autocrine stimulation may represent one property that allows the cells to escape from negative regulation and proliferate in
AML
.
...
PMID:Tumor necrosis factor alpha stimulates the growth of the clonogenic cells of acute myeloblastic leukemia in synergy with granulocyte/macrophage colony-stimulating factor. 266 67
In this study, we further established the role of interleukin-1 (IL-1) alpha and IL-1 beta as regulators of proliferation of
acute myeloid leukemia
(
AML
) cells. IL-1 stimulated tritiated thymidine (3H-TdR) uptake of
AML
cells in 13 of 28 cases. Cytogenetic analysis confirmed the leukemic clonality of the IL-1-stimulated cells. Most likely, IL-1 exerted these stimulative effects directly on
AML
blast cells because IL-1 effectively induced 3H-TdR uptake of CD34-positive
AML
blasts (separated following cell sorting). Furthermore, adherent cell-depleted
AML
samples of three patients were more effectively stimulated than nondepleted
AML
fractions. Cluster and colony formation from adherent cell depleted
AML
samples could also be stimulated with IL-1, ie, in seven of ten cases analyzed. Subsequent experiments indicated that IL-1 stimulation depended on the release of
GM-CSF
because (1) induction of DNA synthesis of
AML
cells by IL-1 could be abrogated with antigranulocyte-macrophage colony-stimulating factor (
GM-CSF
) antibody, (2) conditioned media (CM) prepared from IL-1 stimulated
AML
blasts (adherent cell depleted) could stimulate the proliferation of purified normal bone marrow progenitors whereas supernatants from nonstimulated
AML
blasts did not, and (3)
GM-CSF
was demonstrated in IL-1/
AML
-CM with a specific radioimmunoassay, while
GM-CSF
was not detectable in nonstimulated supernatants. In one case of
AML
showing significant 3H-TdR uptake in the absence of CSFs, this spontaneous DNA synthesis was found to depend on autocrine IL-1 beta release as it could be suppressed with anti-IL-1 beta antibody or anti-
GM-CSF
. The blockade by anti-IL-1 beta could be overcome by the addition of high concentrations of IL-1 beta as well as
GM-CSF
. Thus, in this particular case, endogenously produced IL-1 beta had stimulated the release of
GM-CSF
which resulted in
GM-CSF
-dependent proliferation. The results indicate that
GM-CSF
production by
AML
blasts is often regulated by IL-1 rather than being constitutive.
...
PMID:Interleukin-1 stimulates proliferation of acute myeloblastic leukemia cells by induction of granulocyte-macrophage colony-stimulating factor release. 266 49
Interleukin-2 (IL-2) stimulated H-thymidine incorporation in the blasts of six of 21 cases of
acute myeloid leukaemia
(
AML
). An IL-2 induced increase in cell numbers was directly demonstrated in the two patients studied in this way, and T-cell contamination was rigorously excluded. The IL-2-induced proliferation was usually less marked than that caused by
granulocyte-macrophage colony stimulating factor
(
GM-CSF
), and IL-2 moderately enhanced
GM-CSF
-induced stimulation in five of the six patients; in the sixth, IL-2 and
GM-CSF
were strongly synergistic. IL-2-induced proliferation was observed only in
AML
with a monocytic component (M4/M5), but not all M4/M5 leukaemias responded to IL-2. There was no correlation between expression of the light-chain of the IL-2 receptor and IL-2-induced stimulation. It is suggested that IL-2 is involved at a restricted stage of early myelopoiesis, perhaps when cells are becoming committed to the monocytic lineage; and that IL-2 is a growth factor for early myeloid cells in a proportion of cases of
AML
.
...
PMID:IL-2 and myelopoiesis: IL-2 induces blast cell proliferation in some cases of acute myeloid leukaemia. 268 57
The chromosome alterations specifically associated with leukaemia are found largely in the regions where the genes for the haemopoietic growth factors (as well as other regulatory molecules or their receptors) are located, indicating a crucial role of the growth factors in leukaemogenesis. However, growth factor genes per se do not generally induce leukaemia when inserted into normal haemopoietic cells, although they will do so if they are inserted into immortalized haemopoietic stem cell lines. The response of
AML
cells to these growth factors is extremely heterogeneous, and the tilting of the balance between self-reproduction (leading to perpetuation of the leukaemic process) and differentiation ('death' of the malignant cells) depends on several parameters, on the type and combination of factors to which the cells are exposed, with IL-3 and
GM-CSF
tending to favour self-renewal, and G-CSF and M-CSF tending to favour differentiation. These findings open the possibility to consider the use of growth factors to control the leukaemic process, although such treatment should be approached with considerable caution, and on an individual patient basis.
...
PMID:Haemopoietic growth factors: their role in acute myeloblastic leukaemia. 268 18
We have failed to find any evidence that human recombinant
GM-CSF
can immortalize human
AML
cells grown in liquid culture or as nodules in immune deprived mice. In previous clinical studies and a controlled trial currently underway there is no evidence of irreversible acceleration of the disease.
...
PMID:Failure to immortalise human AML cells using human recombinant GMCSF in vitro and in vivo. 269 35
It has been postulated that the disruption of the normal hormonal regulation of blood cell formation and proliferation leads to the autonomous growth of hematopoietic progenitors or stem cells and thus to leukeamia. We have utilized established hematopoietic cell lines to establish the different mechanism by which growth autonomy is acquired. The analysis of thirteen spontaneous factor-independent mutants revealed that the majority (12/13) secreted a factor that stimulated growth of the parental cell line. Thus, autocrine stimulation may be a important mechanism by which normal growth control is disrupted. This is supported by the observation of Young and Griffin (1987) that some cells isolated from patients with
acute myeloblastic leukemia
(
AML
) autogenously produce growth factor. In the majority of Dind mutants more closely examined, growth factor gene activation was due to the juxtapostion of a retrotransposon. Although the exact nature of the involvement of human retroviruses in inducing leukemia has not been elucidated, one could envisage that altered growth factor regulation due to integration of the virus may play an important role. The existence of a second class of Dind mutants that have obtained factor-independence by a mechanism not involving factor production concurs with the acquisition of factor-independent growth in hematopoietic cells after introduction of some oncogenes. Several models have been proposed to explain how oncogenes may "short circuit" and thus activate the normal signal transduction pathway by mimicking the active receptor, transducer, or effector (Weinberg, 1985). To investigate more closely the role of autocrine stimulation in the induction of growth autonomy and tumorigenicity, retroviral vectors expressing either
GM-CSF
or IL3 were introduced into factor-dependent hematopoitic cell lines. Non-linear clonability of infected cell lines in the absence of exogenous growth factor and inhibition of proliferation by antiserum supported a model of autocrine stimulation. However, a secondary event, correlated with amount of factor released, often occurred that abrogated the requirement for secreted CSF. Growth of cells in which this alteration had occured was cell-density independent and could not be blocked by antibody. It has been postulated that autogenous factor may react with its receptor intracellularly (Lang et al., 1985). The results presented here cannot exclude that the secondary events may allow the internal interaction of receptor and factor.(ABSTRACT TRUNCATED AT 400 WORDS)
...
PMID:Conversion of factor-dependent myeloid cells to factor independence: autocrine stimulation is not coincident with tumorigenicity. 273 34
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