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Query: UMLS:C0026986 (myelodysplastic syndrome)
 14,926 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have previously shown that long-term cultures of adherent layers derived from patients with chronic myelogenous leukemia in blast crisis express high levels of interleukin (IL)-1 beta and that this cytokine may participate in disease progression. In this study, we analyzed cytokine expression in bone marrow adherent layers derived from patients with myelodysplastic syndrome (MDS) and acute myelogenous leukemia (AML). IL-6 messenger RNA (mRNA) was expressed in adherent layers established from four of nine MDS patients, and from 10 of 17 AML patients (including all four individuals in whom AML had evolved from an antecedent MDS state). Similarly, IL-1 beta mRNA was expressed in adherent layers derived from two of nine MDS patients and from three of 17 AML patients. Cultures from two of 10 AML patients who expressed IL-6 also expressed granulocyte (G) colony-stimulating factor (CSF) mRNA. In contrast, IL-1 beta, IL-6, and G-CSF mRNA were not discernible in adherent layers from any of 14 normal volunteers. Transforming growth factor-beta 1, macrophage (M) CSF, IL-7, and leukemia inhibitory factor mRNA as well as IL-6 protein were constitutively expressed in adherent layers derived from both MDS patients, AML patients, and normal bone marrows, whereas IL-1 alpha, tumor necrosis factor-alpha, and GM-CSF were not expressed in either the normal-, MDS- or AML-derived adherent layers. These results indicate that cultured stroma from a subset of MDS and AML patients produce IL-1 beta and/or IL-6. Although, exposure of adherent layers to exogenous IL-1 beta was able to induce IL-6 expression, in 9 of the 14 samples constitutively expressing cytokines, IL-6 transcript levels were elevated without a concomitant increase in IL-1 beta, suggesting that IL-6 transcription was independently dysregulated.
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PMID:Cytokine expression in adherent layers from patients with myelodysplastic syndrome and acute myelogenous leukemia. 783 15

Cytokine treatment in patients with myelodysplastic syndrome (MDS) aims to overcome the maturation defects of myeloid lineage cells associated with cytopenia and cellular dysfunction of mature cells. Since phagocytes play a major role in host defense against microbial infection, we investigated cytokine secretion and oxygen radical release (ORR) from peripheral blood monocytes (PBMC) in a total of 16 MDS patients, 12 patients with refractory anemia (RA) and four patients with RA and excess of blasts (RAEB). Interleukin (IL-6), tumour necrosis factor alpha (TNF alpha), IL-1 beta, and IL-8 secretion from monocytes in response to lipopolysaccharide (LPS) was significantly reduced in the 12 patients with RA compared to 12 healthy controls, whereas no difference was seen in ORR. We further assessed cytokine secretion from monocytes of 10 MDS patients before and after therapy with granulocyte-macrophage colony-stimulating factor (GM-CSF), IL-3, or a combination therapy with GM-CSF and cytosine arabinoside (AraC). In all 10 patients, secretion of IL-1 beta, IL-6, and TNF alpha from PBMC increased after cytokine therapy, whereas IL-8 secretion increased only in five patients with GM-CSF or IL-3 therapy receiving a dosage > or = 250 micrograms/m2 per day but decreased in all other patients. ORR increased in all patients on either GM-CSF or IL-3 therapy. These data indicate that the ability of monocytes to secrete secondary cytokines is impaired in MDS patients but can be restored by in vivo administration of GM-CSF and IL-3.
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PMID:Restoration of impaired cytokine secretion from monocytes of patients with myelodysplastic syndromes after in vivo treatment with GM-CSF or IL-3. 823 Dec 42

A novel long-term cultured interleukin (IL)-3-dependent human myelodysplastic cell line, MDS92, was shown to contain several myeloid-lineage cells such as neutrophils, macrophages, eosinophils, and a small number of megakaryocyte-lineage cells. Therefore this cell line possesses at least bipotential characteristics of myeloid- and megakaryocyte-lineages. Granulocyte colony-stimulating factor clearly promoted the neutrophil alkaline phosphatase activity of MDS92 cells. To the contrary, the incidence and growth of CD41-positive cells were hardly affected by the addition of IL-6, IL-11, c-mpl ligand (thrombopoietin, TPO) or erythropoietin. TPO slightly supported the growth of CD34-positive cell fraction, but not CD41-positive cell fraction of MDS92 cells in combination with IL-3 or Steel factor. This cell line will be a useful tool for the study of MDS stem cells, but the mechanism of commitment of differentiation in MDS stem cells remains unknown.
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PMID:A novel factor-dependent human myelodysplastic cell line, MDS92, contains haemopoietic cells of several lineages. 854 20

The effect of an ex vivo expansion culture system using multiple cytokine combinations was evaluated in 38 cases of myelodysplastic syndrome (MDS) with the aim of overcoming the defective in vitro growth of haemopoietic progenitor cells. A combination of four growth factors (GF) including SCF, IL-3, IL-6 and GM-CSF was identified as the optimal combination for expanding clonogenic progenitor cells in MDS bone marrow liquid cultures. The cultures of 50% of the patients (19/38) responded to GF stimulation (mean CFU-GM fold increase 15.65+/-48 at week 4) and showed morphological features of normal and/or dysplastic myeloid differentiation. In 12/38 cases (31%), complete unresponsiveness to multiple cytokine stimulation was observed; a small number of patients (7/38) showed progressive leukaemic growth along the cultures with the presence of 100% immature blasts at week 4. GM-CSF and c-kit receptors, analysed by immuno-histochemistry in 10 patients, were over-expressed in responding patients and either lacking or down-regulated in non-responders. Fluorescence in situ hybridization (FISH) analysis of cultured interphase cells of nine patients (trisomy 8 in eight patients) showed a clear-cut increase in the percentage of cells with three signals in the two responding patients, thus indicating the expansion of a MDS clone. Multiple cytokine liquid cultures seem to be able to override the refractoriness of MDS progenitor cells to GF stimulation in many cases, revealing a heterogeneity which may have prognostic implications and should be considered in ex-vivo and in vivo clinical trials with cytokine combinations.
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PMID:Response of myelodysplastic syndrome marrow progenitor cells to stimualtion with cytokine combinations in a stroma-free long-term culture system. 861 15

Endogenous plasma levels of granulocyte colony stimulating factor (G- CSF), granulocyte-macrophage colony-stimulating factor (GM-CSF),IL-6 and IL-10 were measured in a total of 70 patients undergoing cytoreductive chemotherapy for treatment of acute leukaemia or non-Hodgkin's lymphomas. the diagnoses were acute myeloid leukaemia (AML; n = 30), acute lymphoblastic leukaemia (ALL;n=6), non-Hodgkin's lymphomas (NHL; n=11) and other malignant haematological disorders including myelodysplastic syndromes (n=23). After chemotherapy, plasma G-CSF was elevated (mean 5.6 ng/ml; range 1.2-10 ng/ml), and was inversely correlated with white blood cell counts (WBC) (r=-0.7, p<0.001). Occurrence of fever (T>38.0 degrees C) during severe myelosuppression (WBC<1x10(9)/1) was associated with an additional increase of G-CSF levels (P<0. (P<0.001). Plasma IL-6 correlated significantly with fever (range <1 to 1100 pg/ml, mean 130 pg/ml; r=0.5, P<0.001) but revealed only a weak association with WBC or platelet counts. In patients treated with recombinant G-CSF (n = 9), an association between IL-6 and fever was still observed after chemotherapy. During the nonfebrile status (total n = 242; AML n = 124), IL-6 levels remained <9 pg/ml in 90% of cases, whereas G-CSF increased with leucopenia (r = -0.72;P<0.001). In contrast, endogenous GM-CSF remained normal and IL-10 showed only a slight increase (21% of samples; maximum 22 pg/ml) in severe leucopenia. In particular, IL-10 levels did not correlate with G-CSF or IL-6 levels. We conclude that systemic release of G-CSF and IL-6 is obviously nit abrogated by cytoreductive chemotherapy in acute leukaemia and NHL may add to the therapeutic efficacy of recombinant cytokines. Also, plasma levels of G-, GM-CSF or IL-6 appear to be regulated by separate mechanisms.
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PMID:Regulated plasma levels of colony-stimulating factors, interleukin-6 and interleukin-10 in patients with acute leukaemia and non-hodgkin's lymphoma undergoing cytoreductive chemotherapy. 861 84

A number of cytokines are used as haemopoietic growth factors and this review focuses on toxicities associated with granulocyte-macrophage colony-stimulating factor (GM-CSF), granulocyte colony-stimulating factor (G-CSF), interleukin (IL)-1, IL-3, IL-4, IL-6 and macrophage colony-stimulating factor (M-CSF). Both GM-CSF and G-CSF, currently approved for clinical use, are generally well tolerated by the majority of patients during short term administration. Constitutional symptoms and bone pain are the most frequently reported adverse effects, but they are rarely treatment-limiting. Reactivation of rheumatoid symptoms, and exacerbation of autoimmune thyroiditis or autoimmune haematological disorders have sometimes been described. Severe cardiovascular complications include the possibility for arterial thromboses and the vascular leak syndrome, which is more specifically observed with GM-CSF. Reports of several cases and small series of patients have suggested that growth factors might increase the pulmonary toxicity of chemotherapy, a possibility that remains debated and requires further attention. Generalised or local cutaneous reactions are frequently noted with GM-CSF. Leukocytoclastic vasculitis was observed with both growth factors, while neutrophilic dermatoses have been mostly described with G-CSF. Exacerbation of psoriasis and isolated anaphylactic reactions have appeared with GM-CSF and G-CSF. The hepatotoxic potential of the growth factors is not clearly established, but the occurrence of coagulation abnormalities has recently been reported. Renal and biological disturbances are usually transient. Long term treatment with GM-CSF and G-CSF also seems to be well tolerated, but the possible occurrence of several adverse events, i.e. bone disorders, leukaemia, unmasking or acceleration of underlying disease, require further investigation in patients receiving prolonged treatment, as in myelodysplasia. Finally, antibodies against growth factors have been reported only with GM-CSF. Other cytokines are still under investigation. Flu-like and constitutional symptoms, sometimes dose-limiting, have been reported with IL-1, IL-3, IL-4 and IL-6, while M-CSF was occasionally associated with such adverse effects. More specific adverse events, also frequently considered as dose-limiting toxicities, include hypotension with IL-1, severe headache or skin rash with IL-3, and nasal congestion and gastroduodenal lesions with IL-4. Severe capillary leak syndrome has been reported only with IL-4. M-CSF toxicity is minimal and limited to reversible but sometimes dose-limiting thrombocytopenia and ophthalmological symptoms with the recombinant product. Again, the safety of long term administration of these cytokines has not yet been determined, and IL-3-induced disease progression in myelodysplastic patients has been suggested.
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PMID:Clinical toxicity of cytokines used as haemopoietic growth factors. 865 81

The survival, proliferation, differentiation and function of normal hematopoietic cells are negatively and positively controlled by various cytokines. Survival and proliferation of leukemic cells appears to be influenced, at least in vitro, by several cytokines. Among the different hematopoietic cell lineages, megakaryocytopoiesis represents a complex and unique hematopoietic system that is thought to be supported by some well-known cytokines; however, the hypothetical lineage-specific main regulator of platelet production, termed thrombopoietin (TPO) had remained elusive. Recently, characterization of the proto-oncogene c-mpl revealed structural homology with the hematopoietic cytokine receptor superfamily, specific expression on cells of the megakaryocytic lineage and functional involvement in megakaryocytopoiesis. Several groups purified and cloned the MPL ligand. Extensive in vitro and in vivo studies have shown that the MPL ligand has activity in stimulating both megakaryocytopoiesis and platelet production proving that this ligand is the long-sought growth factor TPO itself. The MPL receptor was found at the mRNA and/or protein level in 40-80% of primary acute myeloid leukemia (AML) cases in various series. MPL expression was not limited to certain morphological FAB types, although the highest percentages were seen in the M6 (erythroid) and M7 (megakaryocytic) subclasses. Among the myelodysplastic syndromes (MDS), MPL expression was detected in one third of the cases, in particular in refractory anemia with excess of blasts and chronic myelomonocytic leukemia. Lymphoid malignancies such as acute lymphoblastic leukemia (ALL), non-Hodgkin's lymphoma (NHL) and myeloma were MPL-negative. Among the large panel of human leukemia-lymphoma cell lines studied, MPL expression occurred predominantly in lines with erythro-megakaryocytic phenotypes. Nearly all primary and continuously cultured non-hematopoietic solid tumor samples were negative for MPL expression. A significant portion of AML cases and of erythroid, megakaryocytic and myeloid leukemia cell lines co-expressed TPO and MPL mRNA transcripts, although no biologically active TPO appeared to be secreted by these cells. In several studies TPO induced in vitro proliferation of 14-37% of primary AML cases, predominantly of the M2 and M7 subtypes. TPO significantly enhanced the cytokine-induced growth of AML cells in a substantial fraction of cases responsive to GM-CSF, IL-3, IL-6 or SCF. While none of 30 growth factor-independent erythro-megakaryocytic leukemia cell lines responded to TPO with increased proliferation, TPO strongly augmented the growth of several constitutively cytokine-dependent cell lines (eg HU-3, M-07e, TF-1) which can be made TPO-dependent and used as bioassays. Neither in primary cells nor in cell lines did TPO appear to induce any signs of morphological, functional or immunological differentiation. Expression of the MPL receptor is not correlated with a proliferative response to TPO. In summary, extensive studies on normal human and animal cells demonstrated the specificity and function of the MPL receptor and proved that its ligand TPO is the major physiological regulator of megakaryocytopoiesis. The data reviewed here document the wide expression of the MPL receptor on AML cells and also suggest some proliferative effects on certain leukemia cells, apparently on non-megakaryocytic AML cells as well. Thus, experimental evidence supports the notion that TPO may contribute, at least in part, to leukemogenesis, especially in combination with other hematopoietic cytokines which is of clinical significance. TPO-responsive cell lines represent powerful tools for such analyses.
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PMID:Thrombopoietin: expression of its receptor MPL and proliferative effects on leukemic cells. 875 57

Thrombopoietin (TPO) is a novel hematopoietic growth factor that was cloned as a ligand for c-mpl proto-oncogene. The c-mpl proto-oncogene is expressed on various types of human leukemia cell lines derived from erythroid, megakaryocytic, and stem-cell leukemia cells. Also, c-mpl mRNA is detectable on blast cells in about half of acute myeloblastic leukemia (AML) cases regardless of French-American-British (FAB) classification. In the cases with myelodysplastic syndrome, c-mpl is expressed in a substantial fraction of refractory anemia with excess of blast (RAEB), RAEB in transformation, and chronic myelomonocytic leukemia cells, but not in refractory anemia or sideroblastic anemia. Little or no expression of c-mpl mRNA is observed in human lymphoid cell lines and blast cells of acute lymphoblastic leukemia cases. The in vitro treatment of AML cells with TPO resulted in proliferation in about 70% of c-mpl-positive AML cases. The proliferative responses of AML cells to TPO were observed not only in M7-type, but also in the other subtypes of AML cases. Furthermore, the TPO-induced proliferation of AML cells was augmented by the addition of the other hematopoietic growth factors such as interleukin-3 (IL-3), IL-6, stem cell factor, or granulocyte-macrophage colony-stimulating factor. In addition to proliferation, TPO appeared to induce megakaryocytic differentiation in a small part of AML cells. These results suggested that TPO/c-mpl system might contribute, at least in part, to abnormal growth and differentiation of AML cells.
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PMID:The effects of thrombopoietin on the growth of acute myeloblastic leukemia cells. 903 Oct 83

Abnormalities of the expression of cytokines and their receptors seen in myelodysplastic syndromes (MDS) are reviewed. Autocrine and paracrine secretion of growth factors, most notably GM-CSF and IL-6, has been identified as a factor in clone expansion in young pediatric patients with chronic myelomonocytic leukemia. Mutations affecting cFMS, the receptor for M-CSF, have also been demonstrated. The other reported abnormalities have been found in too small a number of cases to explain the cell growth and differentiation disorders seen during the course of MDS. It remains possible, however, that a more detailed study of signal transduction pathways might detect functional abnormalities explaining the contrast between the small number of reported cases with abnormalities at the cytokine and cytokine receptor sites and the cell growth and differentiation disorders that are prominent in MDS.
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PMID:[Abnormalities of the expression of cytokines and their receptors in myelodysplastic syndromes]. 940 81

The levels of IL-1 alpha, IL-2, IL-6 and TNF-alpha were measured immunoradiometrically in the sera of 82 myelodysplastic (MDS) patients at diagnosis in an attempt to identify possible relationships between serum cytokine levels and clinical and laboratory parameters of the patients. We found that serum IL-6 and TNF-alpha concentrations were significantly higher in the group of MDS patients than in the normal controls (p < 0.03 and p < 0.001, respectively), while serum IL-1 alpha and IL-2 levels did not differ statistically between patients and control subjects. Elevated serum IL-6 and TNF-alpha concentrations were mainly seen in patients with high-risk myelodysplasia (MDS), i.e. patients with chronic myelomonocytic leukemia (CMML) (p < 0.05 and p < 0.001, respectively), refractor anemia with excess of blasts (RAEB) (p < 0.01 and p < 0.001, respectively), or refrochopy anemia with excess of blasts in transformation to acute leukemia (RAEB-t) (p < 0.001 and p < 0.001, respectively). Patients with low-risk disease, i.e. patients with refractory anemia (RA) or refractory anemia with ringed sideroblasts (RARS), had serum cytokine levels comparable to those of controls. Patients' serum IL-6 and TNF-alpha correlated inversely with the hemoglobin concentration (p < 0.01 and p < 0.05, respectively) and positively with the absolute number of circulating myeloblasts (p < 0.01 and p < 0.001, respectively) and the proportion of bone marrow (p < 0.001 and p < 0.001, respectively) myeloblasts. A negative correlation was also noted between serum TNF-alpha concentrations and patients' survival in high-risk MDS (p < 0.02). We concluded that elevated serum IL-6 and TNF-alpha values are seen mainly in patients with high-risk disease, and that high serum TNF-alpha concentrations are predictive of shortened survival in this group of patients.
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PMID:Elevated serum TNF-alpha concentrations are predictive of shortened survival in patients with high-risk myelodysplastic syndromes. 970 53


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