Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P05231 (interleukin-6)
 23,907 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

To investigate possible mechanisms of growth factor expression in acute myeloid leukemia, genes for granulocyte macrophage colony-stimulating factor (GM-CSF) were analyzed by Southern blots in 20 patients, for M-CSF in 13, for interleukin-6 (IL-6) in 14, for IL-6 receptor in 14 and for G-CSF in five patients. Only in one patient a complex rearrangement of the G-CSF gene with possible amplification was noted indicating rarity of direct alterations of growth factor genes in acute myelogenous leukemia (AML). Spontaneous m-RNA expression for GM-CSF was found in only one of 20 patients, and for IL-6 in eight of 11 patients. In vitro incubation of AML cells of eight patients with recombinant tumor necrosis factor for 24 hr revealed induction of GM-CSF m-RNA expression in three cases and GM-CSF protein expression in two of them. These data suggest that spontaneous GM-CSF production occurs rarely in AML and that monokines, such as tumor necrosis factor, may induce GM-CSF in AML cells. Therefore, interactions of AML cells with normal or malignant accessory cells may be important for autocrine stimulation in AML. Our data suggest that ectopic growth factor secretion is not the primary cause of generating AML but may contribute to progression of the disease. Alternatively, AML may represent a heterogenous group of leukemias with different etiology but similar phenotype.
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PMID:Mechanisms of growth factor expression in acute myeloid leukemia (AML). 219 15

Proliferation of acute myelogenous leukemia (AML) derived blast cells requires the presence in culture of one or more growth factors. In the majority of cases Interleukin-3 (IL-3) and granulocyte-macrophage colony-stimulating factor (GM-CSF) stimulate clonogenicity of AML blasts, which can be synergised by Interleukin-6 (IL-6), Interleukin-1 (IL-1) and granulocyte colony-stimulating factor (G-CSF). In contrast, macrophage colony-stimulating factor (M-CSF) favors deterministic divisions. A substantial part of AML samples have clonogenic cells which, however, proliferate autonomously in vitro. The production by leukemic cells of a variety of growth or synergizing factors including GM-CSF, G-CSF, IL-1, IL-6, and Tumor Necrosis Factor (TNF) has been demonstrated and a fraction of cases will use these molecules to support clonogenic growth in an autocrine or paracrine fashion. However, unlike the situation with retrovirus-induced murine or avian leukemias, the role of production of CSFs and other cytokines by human leukemic cells in the transformational process remains uncertain.
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PMID:Control of blast cell proliferation and differentiation in acute myelogenous leukemia by soluble polypeptide growth factors. 220 37

The viability of normal bone marrow myeloid precursor cells induced by interleukin-6 (IL-6) or IL-1 alpha and the ability of IL-6 and IL-1 alpha to induce the formation of colonies of granulocytes, macrophages, or megakaryocytes in densely seeded bone marrow cultures was suppressed by transforming growth factor-beta 1 (TGF-beta 1). Induction of normal bone marrow colony formation by IL-3 was much less sensitive to TGF-beta 1, and there was little or no effect of TGF-beta 1 on colony formation induced by macrophage colony-stimulating factor (M-CSF) or granulocyte-macrophage CSF (GM-CSF). In different clones of myeloid leukemic cells, TGF-beta 1 suppressed differentiation induced with IL-6, IL-1 alpha, or lipopolysaccharide (LPS), but did not suppress differentiation induced with IL-3 or GM-CSF. The effect of TGF-beta 1 on differentiation of the leukemic cells can be dissociated from its effect on cell growth. TGF-beta 1 suppressed the production of IL-6 in normal bone marrow cells cultured with IL-1 alpha and the production of IL-6 and GM-CSF in leukemic cells cultured with IL-1 alpha or LPS. The suppression of IL-6 production can explain the suppression by TGF-beta 1 of the effects of IL-1 alpha and LPS that are mediated by IL-6. TGF-beta 1 also suppressed differentiation in clones of myeloid leukemic cells induced with differentiation factor/leukemia inhibitory factor and tumor necrosis factor. In different leukemic clones TGF-beta 1 suppressed or enhanced induction of differentiation with dexamethasone. The results show that TGF-beta 1 can selectively control the activity of different molecular regulators of normal and leukemic hematopoiesis.
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PMID:Selective regulation of the activity of different hematopoietic regulatory proteins by transforming growth factor beta 1 in normal and leukemic myeloid cells. 220 8

The growth-promoting activities of interleukin-6 (IL-6) in combination with different factors were assessed in bone marrow (BM) cultures prepared from normal mice and from mice treated with 5-fluorouracil (5-FU). Effects on hematopoietic colony formation with respect to number, size, and cellular composition were evaluated. In agreement with previous reports, IL-6 acts synergistically with IL-3 to stimulate increased numbers of granulocyte/macrophage (GM) and multilineage colonies in day-2 and day-4 post-5-FU BM cultures. Furthermore, day 4 but not day 2 post-5-FU BM showed enhanced GM colony formation when stimulated with IL-6 plus interleukin-4 (IL-4) or granulocyte colony-stimulating factor (G-CSF). In contrast, IL-6 did not increase the number of colonies supported by M-CSF or GM-CSF. Nevertheless IL-6 interacted with all factors, including M-CSF and GM-CSF, to stimulate an increase in colony size. Many of these myeloid colonies attained a diameter of greater than or equal to 0.5 mm, suggesting they derive from high proliferative potential cells (HPP-CFC). The response of normal and day-8 post-5-FU BM containing high numbers of more mature progenitors was also assessed. We found IL-6 enhanced colony formation by lineage-restricted megakaryocytic and erythroid progenitors in the presence of IL-3 and IL-4 plus erythropoietin (Epo), respectively. The sum of these results shows that IL-6 interacts with a variety of factors to regulate the growth of progenitor cells at different stages of lineage commitment and maturation.
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PMID:Interleukin-6 interacts with interleukin-4 and other hematopoietic growth factors to selectively enhance the growth of megakaryocytic, erythroid, myeloid, and multipotential progenitor cells. 246 2

Purified recombinant granulocyte colony stimulating factor (G-CSF) and interleukin-6 (IL-6) stimulated the formation of similar numbers of colonies in cultures of normal mouse marrow cells. LIF and IL-6 induced comparable differentiation in clonal cultures of murine M1 leukemic cells and exhibited enhanced actions in combination. However, LIF was 16-25-fold more active than IL-6. Induction of differentiation in M1 leukemic colonies by both LIF and IL-6 was enhanced by the addition of G-CSF or M-CSF but not by GM-CSF or Multi-CSF. Both G-CSF and IL-6, but not LIF, were able to induce differentiation in murine WEHI-3B leukemic colonies, but G-CSF was 10-fold more efficient than IL-6. Both G-CSF and IL-6 were able to stimulate the proliferation of cells of the NFS-60 continuous cell line, but G-CSF was 30-fold more efficient. M1 cells constitutively produced low levels of IL-6 and production was enhanced by LIF, but the general characteristics of the actions of LIF, IL-6, and G-CSF suggested that each operates independently as a direct differentiation inducer of leukemic cells. The similarities in the biology and actions of G-CSF, LIF, and IL-6 suggest that they may be designed to exhibit coordinated biological functions in certain situations.
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PMID:Actions and interactions of G-CSF, LIF, and IL-6 on normal and leukemic murine cells. 246 11

There are different types of myeloid leukemic cells that can be induced to differentiate to mature granulocytes or macrophages by different hematopoietic regulatory proteins. One type of leukemic clone can be induced to differentiate by recombinant macrophage and granulocyte differentiation-inducing protein-type 2 (MGI-2), which we have shown is Interleukin-6 (IL-6), and another type of leukemic clone can be differentiated by recombinant granulocyte-macrophage colony-stimulating factor (GM-CSF) or IL-3. There was no subpopulation of growth factor-responsive or differentiation-defective cells before induction of differentiation in either type of clone. In both clones, induction of differentiation-induced requirement for a hematopoietic protein for cell viability. Viability of the cells was maintained by IL-6, IL-3, or macrophage colony-stimulating factor (M-CSF) but not by GM-CSF in the cells differentiated by IL-6, and by GM-CSF or IL-3 but not by IL-6 or M-CSF in the cells differentiated by GM-CSF or IL-3. The viable cells with a differentiated phenotype continued to multiply. In undifferentiated leukemic cells with no or few surface receptors for some of these proteins, there was an upregulation of the number of receptors during differentiation for the proteins to which the cells responded. But there were also differentiating leukemic cells with an upregulation of GM-CSF receptors although GM-CSF could not maintain the viability of the differentiating cells. The results indicate that induction of hormone responsiveness and upregulation of the hormone receptors can both occur in differentiating leukemic cells, and that the regulation of these two events can be separated.
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PMID:Induction of dependence on hematopoietic proteins for viability and receptor upregulation in differentiating myeloid leukemic cells. 254 28

Stromal cells are believed to regulate lympho-hematopoiesis through direct cell-cell interactions and the release of growth factors. Many questions remain, however, about their lineage derivation and functional heterogeneity. We previously prepared a panel of stromal cell lines from murine spleen and bone marrow and characterized them based on their ability to support lymphocyte growth in long-term cultures. These cells are now compared with respect to their expression of various immunoglobulin superfamily and cytokine genes by Northern blot analysis. These results indicate that although stromal cells appear to be mesodermal in origin, they are not closely related developmentally to the hematopoietic progenitor cells they support. The potential production of at least six cytokines was demonstrated. All clones constitutively expressed mRNA for macrophage colony stimulating factor, interleukin-6, transforming growth factor beta and neuroleukin. The most potent lymphocyte supporting clones also made interleukin 7 constitutively. Previous findings had suggested that these clones responded to exogenous stimuli and this has now been demonstrated in terms of induced expression of IL-6 and G/M-CSF mRNA. Interleukin 6 mRNA levels were markedly upregulated by exposure of cells to LPS, TNF, IL-1, IL-6, IL-7, and EGF. G/M-CSF mRNA levels were "superinduced" by the combination of LPS and cycloheximide, a protein synthesis inhibitor. These responses are similar to ones documented by investigators working with endothelial cells and fibroblasts. Together, these data suggest that stromal cells are a multifunctional component of the lymphopoietic microenvironment and may be active participants in a complex, cytokine-mediated regulatory network.
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PMID:Characterization of murine bone marrow and spleen-derived stromal cells: analysis of leukocyte marker and growth factor mRNA transcript levels. 256 60

We examined the in vitro stimulative effects of recombinant human interleukin-6 (IL-6, or interferon-beta 2) on purified human bone marrow progenitor cells. IL-6 alone or in combination with erythropoietin (Epo), IL-3, GM-CSF, or G-CSF did not induce colony formation. However, IL-6 strongly synergized with M-CSF in stimulating macrophage colony formation (colony numbers and size). The magnitude of IL-6 synergism with M-CSF was dose dependent; maximal potentiation of M-colony formation was evident at approximately 100 to 1,000 U/mL IL-6. When the addition of IL-6 to M-CSF-supplemented cultures was delayed for more than one day after the beginning of culture, enhancement of macrophage colony formation was lost. IL-6 stimulation of M-CSF-responsive colony formation was not apparent when nonpurified marrow cells were plated, most likely due to endogenous IL-6 release. These observations suggest that IL-6, in addition to playing a role in B-lymphocyte proliferation can potentiate the human immune defence mechanism by stimulating monocyte-macrophage development as well.
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PMID:Interleukin-6 synergizes with M-CSF in the formation of macrophage colonies from purified human marrow progenitor cells. 264 76

The central feature of hemopoiesis is life-long, stable cell renewal. This process is supported by hemopoietic stem cells which, in the steady state, appear to be dormant in cell cycling. The entry into cell cycle of the dormant stem cells may be promoted by such factors as interleukin-1, interleukin-6 (IL-6), and granulocyte colony-stimulating factor (G-CSF). Once the stem cells leave G0 and begin proliferation, the subsequent process is characterized by continued proliferation and differentiation. While several models of stem cell differentiation have been proposed, micromanipulation studies of individual progenitors suggest that the commitment of multipotential progenitors to single lineages is a random (stochastic) process. The proliferation of early hemopoietic progenitors requires the presence of interleukin-3 (IL-3), and the intermediate process appears to be supported by granulocyte/macrophage colony-stimulating factor (GM-CSF). Once the progenitors are committed to individual lineages, the subsequent maturation process appears to be supported by late-acting, lineage-specific factors such as erythropoietin and G-CSF. Synthesis of a hemopoietic factor may take place in different cell types and is regulated by multiple factors. The physiological regulator of erythropoiesis is erythropoietin, which, by a feedback mechanism, provides fine control of erythrocyte production. Feedback mechanisms for leukocyte production have not been identified. It is possible that there is no feedback regulator of leukopoiesis. In this model, leukocyte production in the steady state is maintained at a genetically determined level. When an infection occurs, the bacterial lipopolysaccharides may augment the production of interleukin 1 alpha and beta, tumor necrosis factor, macrophage colony-stimulating factor, etc.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Hemopoietic stem cells: stochastic differentiation and humoral control of proliferation. 264 80

Tumor cells were isolated from the bone marrow of seven patients with multiple myeloma and from the peripheral blood of three patients with plasma cell leukemia using Ficoll-Hypaque (FH) density sedimentation followed by immune rosette depletion of T, myeloid, monocytoid, and natural killer (NK) cells. Enrichment to greater than or equal to 93% plasma cells was confirmed with Wright's-Giemsa staining, with intracytoplasmic immunoglobulin staining, and with staining using monoclonal antibodies (MoAbs) directed at B, T, myeloid, monocytoid, and myeloma antigens in indirect immunofluorescence assays. Myeloma cells neither proliferated nor secreted Ig in response to G/M-CSF, G-CSF, M-CSF, interleukin-1 alpha (IL-1 alpha), interleukin-1 beta (IL-1 beta), interleukin-2 (IL-2), or interleukin-4 (IL-4). Significant proliferation (SI greater than or equal to 3.0) was induced by interleukin-6 (IL-6) in six of ten patients (SI of 31 and 43 in two cases); and to interleukin-3 (IL-3) and interleukin-5 (IL-5), independently, in two patients each. Peak proliferation to IL-5 or IL-6 and to IL-3 occurred in cells pulsed with 3[H] thymidine at 24 and 48 hours, respectively; and proliferation to combinations of factors did not exceed that noted to IL-6 alone; Ig secretion was not documented under any culture conditions. Three myeloma-derived cell lines similarly studied demonstrated variable responses. The heterogeneity in the in vitro responses of myeloma cells and derived cell lines to exogenous growth factors enhances our understanding of abnormal plasma cell growth and may yield insight into the pathophysiology of plasma cell dyscrasias.
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PMID:Response patterns of purified myeloma cells to hematopoietic growth factors. 271 8


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