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

Sera of 25 healthy controls and 75 patients suffering from myelodysplastic syndromes (MDS) were investigated for serum concentration of interleukin-1 alpha (IL-1 alpha), IL-3, IL-6, granulocyte-colony-stimulating factor (G-CSF), granulocyte-macrophage-CSF (GM-CSF), erythropoietin (Epo), and tumor necrosis factor-alpha (TNF-alpha). According to French-American-British (FAB) classification, 21 refractory anemia (RA), seven refractory anemia with ring sideroblasts (RARS), 15 chronic myelomonocytic leukemia (CMML), 12 refractory anemia with excess of blasts (RAEB), and 20 RAEB in transformation (RAEBt) were examined. TNF-alpha levels were inversely correlated with lower levels of hemoglobin concentration (r = -0.31, p = 0.005), irrespective of the requirements for transfusion in anemic MDS patients. Significant differences in TNF-alpha levels between CMML (26.2 +/- 5.9 pg/ml) and the FAB subgroups (16.1 +/- 1.6 pg/ml) were detected. There was an overall inverse relationship between the level of erythropoietin and the degree of anemia, but a wide range of Epo response between patients with similar hemoglobin concentrations. Serum levels of IL-1 alpha and GM-CSF were undetected in most of the patients. In 57% of the samples there were detectable levels of G-CSF, without a correlation of the serum levels with blood cell counts, nor with any of the FAB subcategories. Overall, 29% and 25% of the patient sera exhibited elevated IL-3 and IL-6 levels, respectively. There was no correlation of the serum levels with any of the blood counts, other cytokines, nor FAB subcategories. In conclusion, simple negative feedback mechanism between a specific cytokine and the production of blood cells seems not to be the case in MDS, except for red cell production and erythropoietin concentration. Our data may suggest the involvement of TNF-alpha in the pathogenesis of anemia in MDS.
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PMID:Measurement of serum cytokine levels in patients with myelodysplastic syndromes. 128 Jul 51

A number of cloned biologic factors are currently available that are candidates for therapy of myelodysplastic syndromes and, by extension, acute nonlymphoblastic leukemia. gamma-Interferon and, to a greater extent, tumor necrosis factor exhibit leukemic differentiative effects without the potential for stimulation of leukemic clones. These effects may be enhanced by combinations of these with one another or with chemical inducers of differentiation such as retinoic acid or vitamin D derivatives. The colony-stimulating factors clearly have potent in vivo effects upon hematopoiesis. The lineage specific factors (G- or M-CSF) may have greater differentiation induction potential and less risk of accelerating emergence of leukemic clones than the earlier acting factors (GM- or multi-CSF). Thus, several potentially fruitful avenues for clinical research are currently available.
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PMID:The basis for treatment of myelodysplastic syndrome and acute nonlymphoblastic leukemia with biologic agents. 245 61

The effects of recombinant human interleukin 3 (IL3) on normal bone marrow cells and human leukemic cells were studied. In clonal assays, IL3 supported the growth of all colony types including megakaryocytes. Erythroid colonies were formed in the presence of IL3 and erythropoietin, but not in the absence of erythropoietin. Replating experiments using blast cell colonies derived from a cell population enriched for progenitor cells by fluorescence-activated cell sorting with the monoclonal antibody 3C5, showed that IL3 supported the continued replating of colonies. The clonal proliferation of human bone marrow cells in response to IL3 was inhibited by tumor necrosis factor and by lymphotoxin, but not by interferon-gamma. In suspension cultures, IL3 supported the proliferation of mast cells. Human IL3 had no effect on the growth responses, morphology, cytochemistry, or clonogenicity of the human leukemic cell lines HL60, U-937, KG1a, and HEL. Transcripts for IL3 mRNA were not detectable in these cells, nor in the K562 cell line, implying that autocrine secretion of IL3 was not the mechanism by which these leukemias were maintained. Although cells derived from the bone marrow or peripheral blood of twenty patients with myeloproliferative disorders, myelodysplastic syndromes or acute myeloid leukemia frequently showed proliferative responses to IL3, mRNA transcripts for IL3 were not detected in these cells.
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PMID:Human interleukin 3: effects on normal and leukemic cells. 262 75

Human acute myelogenous leukemia often arises from a transformation at the stem cell level leading to a block in differentiation. The malignant cell, therefore, remains in the proliferative pool and rapidly accumulates. In preleukemia, also known as myelodysplastic syndromes, the malignant clone is already established, leading to disturbed hematopoiesis. One therapeutic approach, therefore, might be to overcome this block in differentiation and thus shift the cell from the proliferative into the differentiating pool. For several years now research in leukemia has focused on study of the proliferation and differentiation of normal and leukemic hematopoietic cells. Numerous substances have been identified which are able to trigger differentiation in myeloid cells, including the retinoids, vitamin D, tumor necrosis factor and hematopoietic hormones. The possible role of these agents in the treatment of preleukemia and acute myelogenous leukemias is discussed.
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PMID:[Induction of myelogenous differentiation: a therapeutic possibility for preleukemia and acute leukemia?]. 329 Nov 4

Recombinant interleukin 2 (rIL 2, Cetus) was administered in escalating doses to 30 patients with advanced malignancy, including 14 patients with the epidemic form of Kaposi's sarcoma, in 2 week treatment cycles as a 6 h i.v. infusion for 10 doses. The maximum tolerated dose was 2 X 10(6) U/m2, with dose-limiting toxicity consisting of fever, diarrhea, and thrombocytopenia. At a well-tolerated dose of 1 X 10(6) U/m2, serum levels of rIL 2 of 30 U/ml were maintained for the duration of the infusion. Such concentrations sustain IL 2-dependent T cell growth in vitro. We observed a significant lymphocytosis in patients receiving 1 X 10(6) U/m2 of rIL 2 following 2 weeks of treatment (p = 0.0035). The expanded T cell pool was polyclonal, as demonstrated by increases in both T4+ and T8+ T cell subsets, and activated, with statistically significant increases in IL 2 receptor (p = 0.043), in the absence of transferrin receptor induction. Proliferating cells were not detected in peripheral blood using flow cytometry. Except for alpha-interferon, no other lymphokines (beta- and gamma-interferon, tumor necrosis factor) were present in serum during treatment. Reversible rises in anti-rIL 2 IgG antibodies occurred, as measured using an enzyme-linked immunosorbent assay. No changes were observed in the T cell mitogenic response to OKT3 and phytohemagglutinin, and no enhancement of cytotoxicity against natural killer-sensitive and resistant targets developed as a consequence of treatment. Except for a partial response in a patient with a myelodysplastic syndrome, no antitumor activity was observed. The in vivo expansion of T cells with the capacity to respond to rIL 2 with enhanced in vitro cytotoxicity against tumor targets provides impetus to ongoing trials exploring different routes and schedules of administration of rIL 2.
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PMID:Expansion of activated T-lymphocytes in patients treated with recombinant interleukin 2. 349 11

We studied spontaneous cytokine production by peripheral blood mononuclear cells (PBMC) obtained from 14 patients with aplastic anemia (AA) and 28 various myelodysplastic syndromes (MDS). The levels of interleukin-6, interleukin-1 beta, and tumor necrosis factor-alpha in cultured PBMC were measured by ELISA. The average levels of these cytokines were higher in AA or in refractory anemia (RA) than in RA with excess of blasts (RAEB) or in RAEB in transformation (RAEB-T). Marked cytokine overproduction was observed in RA as well as in AA. High cytokine levels were observed in hypocellularity and low blast cell counts in the bone marrow. These results may suggest that the increase of cytokines may be a reactive response in hypocellular bone marrow.
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PMID:Spontaneous cytokine overproduction by peripheral blood mononuclear cells from patients with myelodysplastic syndromes and aplastic anemia. 756 74

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

Because human lymphotoxin (LT) was originally isolated from a lymphoblastoid cell line, we investigated the role of this molecule in three newly established Epstein-Barr virus (EBV)-infected human B cell lines. These lines were derived from acute lymphoblastic leukemia (Z-6), myelodysplastic syndrome (Z-43), and acute myelogenous leukemia (Z-55) patients who had a prior EBV infection. Each lymphoblastoid cell line had a karyotype that was different from that of the original parent leukemic cells, and all expressed B cell, but not T cell or myeloid surface markers. In all three lines, rearranged immunoglobulin heavy chain joining region (JH) bands were found, and the presence of EBV DNA was confirmed by Southern blotting. Z-6, Z-43, and Z-55 cell lines constitutively produced 192, 48, and 78 U/ml LT, respectively, as assessed by a cytotoxicity assay and antibody neutralization. Levels of tumor necrosis factor (TNF) were undetectable. Scatchard analysis revealed that all the cell lines expressed high-affinity TNF/LT receptors with receptor densities of 4197, 1258, and 1209 sites/cell on Z-6, Z-43, and Z-55, respectively. Furthermore, labeled TNF binding could be reversed by both unlabeled TNF, as well as by LT. Studies with p60 and p80 receptor-specific antibodies revealed that the three lines expressed primarily the p80 form of the TNF receptor. When studied in a clonogenic assay, exogenous LT stimulated proliferation of all three cell lines in a dose-dependent fashion at concentrations ranging from 25 to 500 U/ml. Similar results were obtained with [3H]TdR incorporation. Monoclonal anti-LT neutralizing antibodies at concentrations of 25-500 U/ml inhibited cellular multiplication in a dose-dependent manner. It is interesting that in spite of a common receptor, TNF (1,000 U/ml) had no direct effect on Z-55 cell growth, whereas it partially reversed the stimulatory effect of exogenous LT. In addition, TNF inhibited Z-6 and Z-43 cell proliferation, and its suppressive effect was reversed by exogenous LT. Both p80 and p60 forms of soluble TNF receptors suppressed the lymphoblastoid cell line proliferation and their inhibitory effect was partially reversed by LT. Our data suggest that (a) LT is an autocrine growth factor for EBV-transformed lymphoblastoid B cell lines; and (b) anti-LT antibodies, soluble TNF/LT receptors, and TNF itself can suppress the growth of lymphoblastoid cells, probably by modulating or competing with LT.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Lymphotoxin is an autocrine growth factor for Epstein-Barr virus-infected B cell lines. 838 56

Nine patients (median age, 58; range: 37-74) with relapsed de novo acute myeloid leukemia (AML) (3), AML after prior myelodysplastic syndrome (MDS) (4), or MDS (2) were treated with 2-20 x 10(6) U/m2/day (1-10 mg/m2/day) of recombinant human interferon gamma (rIFN gamma; Biogen) on a 14-day continuous intravenous infusion schedule. The two patients who received the initial dose of 20 x 10(6) U/m2/day (1.0 mg/m2/day) could only tolerate 6 days of therapy because of severe hepatotoxicity. Two patients who received the revised starting dose of 10 x 10(6) U/m2/day also could not complete a full course of rIFN gamma due to renal failure in one case and pulmonary deterioration in the other. A reversible dose-related rise in SGOT was seen in six patients. All patients developed a severe flu-like syndrome characterized by myalgias and fevers. These toxicities were not associated with detectable serum levels of tumor necrosis factor (TNF). Although blasts from three of five assessable patients displayed increased expression of the Ia (HLA-DR) antigen, there were no hematological responses. Steady-state rIFN gamma plasma levels in patients who tolerated a complete infusion were < 40 U/ml, a concentration below that required to induce differentiation of myeloid leukemic cell lines in vitro. We conclude that continuous infusions of rIFN gamma at doses as low as 2 x 10(6) U/m2/day are poorly tolerated in patients with AML and MDS; the maximum tolerated dose is approximately 2 x 10(6) U/m2/day.
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PMID:Recombinant human gamma interferon administered by continuous intravenous infusion in acute myelogenous leukemia and myelodysplastic syndromes. 845 11

This paper reports on the production of tumor necrosis factor (TNF) and granulocyte macrophage colony-stimulating factor (GM-CSF) by cultured mononuclear adherent cells derived from bone marrow of 25 patients affected by myelodysplastic syndrome (MDS) of different FAB subtypes. Mean production of GM-CSF was much lower than in controls, without significant differences among different subtypes. Mean production of TNF was similar in MDS patients and in controls, but noteworthy differences were observed between patients with RA, RAEB and RAEB-t and patients with RARS and CMML. Growth of bone marrow granulocyte macrophage and erythroid progenitors did not correlate with TNF and GM-CSF production, although in MDS subtypes with higher GM-CSF levels, colony growth was slightly higher than in subtypes with lower GM-CSF production.
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PMID:Producton of tumor necrosis factor and granulocyte colony stimulating factor by bone marrow accessory cells in myelodysplastic patients. 859 33


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