Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: 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)

Leukaemia inhibitory factor (LIF) acts on the growth and differentiation of haematopoietic cells. By using a specific enzyme-linked immunosorbent assay for human LIF, we demonstrate that human bone marrow stromal cells produce LIF. LIF synthesis is enhanced in a dose-dependent manner after stimulation with lipopolysaccharide (LPS) and phorbol 12-myristate 13-acetate (PMAS). LIF production in response to PMA is PKC-dependent since the two PKC inhibitors sphingosine and staurosporine markedly diminished it. Interleukin 1alpha (IL-1alpha), IL-1beta, IL-3, IL-6, IL-8, tumour necrosis factor (TNF-alpha) and SCF (both at 10 ng/ml) stimulate LIF production. By contrast macrophage colony-stimulating factor (M-CSF), granulocyte (G)-CSF, GM-CSF, basic fibroblast growth factor (bFGF), platelet-activating factor (PAF), protaglandin E2 (PGE2), leukotriene B4 (LTB4), and leukotriene C4 (LTC4) did not. These results suggest that bone marrow stromal cells might represent a major source for the cytokine-regulated local production of LIF inside human bone marrow.
Cytokine 1997 Oct
PMID:Spontaneous and inducible production of leukaemia inhibitory factor by human bone marrow stromal cells. 934 7

The regulation of macrophage lipoprotein lipase (LPL) by cytokines is of potentially crucial importance in the pathogenesis of atherosclerosis. The effect of combinations of interleukin 1 (IL-1), 6 (IL-6), and 11 (IL-11), interferon gamma (INF-gamma), leukaemia inhibitory factor (LIF) and tumour necrosis factor alpha (TNF-alpha) on the expression of LPL in macrophages was studied using the murine J774.2 cell line. The suppression of heparin-releasable LPL activity produced by combinations of IL-1 and IL-11, IL-1 and TNF-alpha, IL-11 and TNF-alpha, and, IL-11 and INF-gamma was substantially lower than that expected from the additive action of the corresponding two cytokines. By contrast, co-exposure of cells to LIF and IFN-gamma, IL-6 and LIF, and INF-gamma and TNF-alpha resulted in a more than additive, synergistic, suppression of LPL activity with the maximum reduction and maximum degree of synergism produced by combinations of IFN-gamma and TNF-alpha. The synergism between IFN-gamma and TNF-alpha was observed over a range of complementary dose combinations and also occurred when the cells were exposed first to INF-gamma (priming), washed, and then stimulated subsequently with TNF-alpha. The reduction in LPL activity by combinations of IFN-gamma and TNF-alpha and the priming action of IFN-gamma were accompanied by a comparable decrease in LPL mRNA concentrations, thereby indicating that the major control responsible for the changes in LPL activity was being exerted at the level of mRNA metabolism (decreased transcription or RNA stability). These results suggest that the modulation of macrophage LPL function in atherosclerosis by cytokine combinations may be more important than the presence or absence of any given cytokine.
Cytokine 1998 Jan
PMID:Synergism between interferon gamma and tumour necrosis factor alpha in the regulation of lipoprotein lipase in the macrophage J774.2 cell line. 950 44

Fifty-five adult patients with primary bone tumour, 27 benign and 28 malignant tumours, were assayed for leukaemia inhibitory factor (LIF) in urine and serum samples. Supernatant was obtained from primary tumour tissue cultures in 24 cases (14 benign, 10 malignant tumours). LIF was found in 11 urine samples (16.7%, 1 benign and 10 malignant tumours). In 23 urine samples from patients with malignant bone tumour tested before any treatment, LIF was detectable in eight cases (34.7%). High LIF levels were found in all supernatants from malignant tumour cultures and in supernatant from 12 of the 14 benign tumours cultured. LIF was never detected in control urine samples or supernatants from normal cancelous bone cultures. These first in vivo data concerning LIF in primary bone tumours raise the question as to the cellular origin of this multifunctional cytokine and its potential role in solid bone tumours and bone tumour resorption.
Cytokine 1998 Feb
PMID:Increased levels of leukaemia inhibitory factor (LIF) in urine and tissue culture supernatant from human primary bone tumours. 951

Leukaemia inhibitory factor (LIF) and oncostatin M (OSM) exhibit pleiotropic biological activities, share many structural and genetic features and bind with high affinity to the same receptor (LIF/OSM receptor). A soluble form of the LIF-R alpha, called LIF binding protein (LBP) has been isolated from mouse serum. LIF and OSM stimulate proteoglycan (PG) release and inhibit PG synthesis in cultured pig articular cartilage explants. The aim of this study was to determine whether LBP can block PG resorption and or reverse the inhibition of PG synthesis induced by LIF and OSM. In cultured pig cartilage explants LBP was found to dose dependently inhibit LIF stimulated release of PGs and reverse the suppression of PG synthesis. LBP was found to substantially attenuate the effects of LIF. In contrast only partial inhibition of the stimulatory effect of OSM was observed at the highest concentration of LBP available. At maximal concentrations, LBP produced minimal reversal of OSM mediated inhibition of PG synthesis. When tested in combination LIF and OSM had no additive effects on PG metabolism, but the combination of LIF and IL-1 and also OSM and IL-1 did show additive effects in respect to stimulation of PG catabolism and inhibition of PG synthesis. These effects were significantly greater than those observed for LIF, OSM and IL-1 alone. The results suggest that pig articular chondrocytes possess the LIF/OSM receptor, but possibly not an independent OSM receptor. The actions of mLBP indicate that rhLBP could be a clinically useful antagonist for LIF and perhaps OSM.
Cytokine 1998 Mar
PMID:Modulation of cartilage proteoglycan metabolism by LIF binding protein. 957 68

Oncostatin M (OSM) is a cytokine produced by activated T lymphocytes and macrophages. OSM is structurally and functionally related to leukaemia inhibitory factor (LIF), another cytokine in the interleukin 6 (IL-6) family. The biological activities of OSM are mediated through two types of receptor complexes, the LIF/OSM shared receptor (type I) and OSM-specific receptor (OSM-R, type II), which is composed of gp130 as a binding subunit and a newly identified affinity conversion subunit, OSM-R beta. Previous research conducted in the authors' laboratory has shown that OSM inhibits the growth of several breast cancer cell lines. To investigate whether OSM has a similar effect in primary normal human mammary epithelial (HME) cells, the activity of OSM in HME cells derived from four donors was examined. OSM produced a dose-dependent inhibition of DNA synethesis in these cells. In order to determine the receptor subtypes mediating OSM activity in HME and breast cancer cells, flow cytometry analysis using anti-gp130mAb and anti-OSM-R beta mAb was performed. In these studies, the authors were able to examine expressions of gp130 and OSM-R beta. In addition, quantitative RT-PCR assays were conducted to measure expressions of the mRNAs of the subunits for type I and type II OSM receptor. The results show that HME cells and most breast cancer cell lines express both the type I and the type II OSM receptors. However, type II, OSM-specific receptors are expressed at a higher levels than type I, OSM/LIF shared receptors. Accordingly, we compared the growth regulatory activities of OSM with LIF in HME cells and in breast cancer cells. In contrast to the inhibitory activity of OSM, LIF stimulated the growth of breast cancer cells, whereas it had no effect on normal mammary epithelial cell growth. Together, these data suggest that OSM plays an inhibitory role in normal and malignant mammary epithelial cell growth in vitro. OSM activity is mediated by the OSM-specific receptor (type II), not by the OSM/LIF shared receptor.
Cytokine 1998 Apr
PMID:Oncostatin M-specific receptor expression and function in regulating cell proliferation of normal and malignant mammary epithelial cells. 961 75

In this study the authors assessed plasma leukaemia inhibitory factor (LIF), interleukin 6 (IL-6) and soluble IL-6 receptor (sIL-6R) concentrations in 28 patients undergoing coronary artery bypass graft (CABG) with extracorporeal circulation (ECC). Plasma IL-6 levels increased during ECC, reaching a 33-fold increase 6 h after surgery as compared to pre-operative values. In contrast, plasma sIL-6R and LIF concentrations did not vary significantly during cardiac surgery. Thus, LIF is not implicated in the haematological changes and in the inflammatory syndrome observed after CABG. Despite the fact that LIF and IL-6 exhibit several common biological activities, the production of these two cytokines is differently regulated during cardiac surgery with ECC. Plasma IL-6 levels increased during cardiac surgery while sIL-6R levels did not changed. These data contrast with the decreased sIL-6R concentrations with concomitantly high IL-6 levels in patients with sepsis syndrome suggesting that inflammatory reactions in sepsis and after cardiopulmonary bypass are triggered by different mechanisms.
Cytokine 1998 Apr
PMID:Plasma leukaemia inhibitory factor, interleukin 6 and soluble interleukin 6 receptor levels during cardiopulmonary bypass with extracorporeal circulation. 961 76

The acute phase response to inflammation is mediated in part by the endogenous production of pro-inflammatory cytokines. Interleukin 6 (IL-6) and members of its superfamily, including ciliary neurotrophic factor (CNTF) and leukaemia inhibitory factor (LIF) have been implicated as primary mediators of the hepatic acute phase response. In the present report, mice suffering a turpentine-induced myositis were passively immunized with antibodies against either IL-6, CNTF or LIF. Passive immunization against IL-6 attenuated the anorexia and completely prevented the hypoalbuminaemia, and increases in the serum concentration of the acute phase reactants, amyloid P, amyloid A and seromucoid. In contrast, passive immunization against either CNTF or LIF failed to modulate the anorexia, weight loss or hepatic acute phase protein responses. The findings suggest that IL-6, but not other members of its superfamily, is primarily responsible for the hepatic acute phase response, and contributes to the anorexia, associated with turpentine-induced myositis.
Cytokine 1998 Jun
PMID:Interleukin 6, but not ciliary neurotrophic factor or leukaemia inhibitory factor, is responsible for the acute phase response to turpentine-induced myositis. 963 32

Despite sufficient levels of HLA class I and class II expression, acute myeloid leukemia (AML) cells usually fail to induce a significant T-cell response in vitro. Therefore, we investigated whether in vitro modifications could enhance the T-cell stimulatory properties of AML cells. AML cells were either cultured with granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin-4 (IL-4), and tumor necrosis factor-alpha (TNF-alpha), or transfected with the CD80 (B7.1) gene and used as stimulator cells for primed and unprimed allogeneic T cells. Cytokine treatment increased HLA class I and II expression, but did not induce CD80 on AML cells. Cytokine-treated AML cells efficiently presented nominal and allo-antigens to primed T-cell clones, induced strong T-cell proliferation in HLA mismatched mixed lymphocyte reactions (MLR), but failed to induce primary T-cell responses from an HLA identical bone marrow donor in MLR. In contrast, CD80-transfected AML cells induced T-cell proliferation of HLA-identical bone marrow donor peripheral blood mononuclear cell (PBMC) in primary MLR, allowing the generation of leukemia reactive CD4(+) T-cell lines and clones. The majority of the generated oligoclonal (25 of 35) T-cell cultures showed patient specific reactivity that did not discriminate between patient's leukemic cells and Epstein-Barr virus (EBV)-transformed B cells (EBV-LCL). The remaining 10 oligoclonal T-cell cultures recognized only leukemic cells. One of these latter leukemia reactive oligoclonal T cells was cloned. The majority of the clones (25 of 29) reacted against both leukemic cells and patient's EBV-LCL. A minority of the T-cell clones with the CD4 phenotype (four of 29) showed strong HLA-DP restricted reactivity against leukemic cells, but not against patient's EBV-LCL or against HLA-matched nonleukemic cells, indicating that their target antigens are preferentially expressed by leukemic cells. In conclusion, our study shows that the in vitro allogeneic T-cell response induced by CD80-transfected AML cells is mainly directed against patient's specific minor histocompatibility antigens, while antigens preferentially expressed by leukemic cells can also trigger T-cell responses.
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PMID:CD80-Transfected acute myeloid leukemia cells induce primary allogeneic T-cell responses directed at patient specific minor histocompatibility antigens and leukemia-associated antigens. 971 96

In order to scrutinize the adherence-dependent interactions for induction of granulocyte colony-stimulating factor (G-CSF) in peripheral monocytes/macrophages, a sensitive reporter gene assay was constructed using the mouse macrophage cell line transfected with the mouse G-CSF promoter region in conjunction with the luciferase gene as a reporter. With this system, lipopolysaccharide (LPS) showed a markedly positive response. Among the extracellular matrix (ECM) proteins, both fibronectin (FN) and vitronectin (VN) markedly induced luciferase activity, but others did so but much lesser extent. Among the synthetic peptides having Arg-Gly-Asp (RGD) sequences, only FLEPP with multiple RGD significantly induced luciferase activity. Pretreatment of the cells with anti-integrin alpha 6, alpha M, beta 1 and beta 2 monoclonal antibodies (mAbs) significantly reduced the LPS-induced responses and anti-alpha 1, alpha 2 and beta 3 mAbs to lesser extent, and anti-alpha 5, alpha 6, alpha M, beta 1 and beta 2 mAbs blocked the FN-induced response. In the cell-to-cell interactions, significantly positive increase was observed by direct contacting this cell line with a G-CSF-dependent promyelocytic leukaemia cell line, known to stimulate the induction of G-CSF to the stromal cells. Its effect was mostly blocked by pretreatment with anti-integrin alpha 5, alpha L, beta 1 and beta 2 and anti-ICAM-1 mAbs. These results indicate that there are several pathways via the cell-to-ECM and cell-to-cell interactions triggering the induction of G-CSF in the macrophages.
Cytokine 1998 Aug
PMID:Stimulation of G-CSF gene expression in the macrophage cell line by contact with extracellular matrix proteins and a pre-B leukaemia cell line. 972 32

Acute myeloid leukaemia (AML) cells express the SCF receptor c-kit (CD117) on their cell surface and demonstrate enhanced adhesion to fibronectin (FN) following exposure to stem cell factor (SCF). Increased adhesion occurs within 5 min, is dose dependent, and persists beyond 2 h. Baseline and enhanced adhesion occur through the surface FN receptor very late antigen-5 (VLA-5, CD49e/CD29) which is expressed by AML cells. Unstimulated AML cells exposed to FN undergo less apoptosis than controls (inhibition 22.5 +/- 7.0%, P = 0.02, n = 8). Exposure to SCF alone without FN also inhibits AML cell apoptosis (by 19.0 +/- 7.7% compared to controls, P = 0.06, n = 8). Simultaneous exposure to SCF and FN increases the inhibition of AML cell apoptosis to 37.8 +/- 7.9% (P = 0.005 compared to control, P = 0.04 compared to FN alone, P = 0.06 compared to SCF alone) demonstrating that SCF not only enhances the propensity of AML cells to adhere to FN, but also results in an additive survival benefit following FN contact. Some but not all the reduction in apoptosis is mediated through VLA-5. The combination of SCF and FN also affects proliferation, resulting in a synergistic enhancement of AML cell proliferation in half the cases studied. When normal CD34+ human haemopoietic progenitors were studied, FN had little effect on their apoptosis and failed to enhance the anti-apoptotic effect of SCF. It did, however, synergise with SCF in promoting CD34+ cell proliferation. Exposure of AML cells to SCF and FN, both of which can be found in high concentration in the bone marrow stroma, inhibits apoptosis. Cytokines and extracellular matrix proteins augment each others' effects since SCF enhances adhesion to fibronectin, which in turn augments the survival signal delivered by the cytokine alone. Cytokine and adhesion receptors can combine to affect cell characteristics including proliferation and survival.
Leukemia 1998 Sep
PMID:Stem cell factor enhances the adhesion of AML cells to fibronectin and augments fibronectin-mediated anti-apoptotic and proliferative signals. 973 85


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