Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0023418 (leukemia)
 93,477 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

To determine the mechanism of the purified protein derivative (PPD)-specific hyporesponsiveness in Mycobacterium bovis BCG-vaccinated human T-cell leukemia virus type 1 (HTLV-1)-infected individuals, we examined cytokine production in response to PPD in the following four groups of individuals: (i) HTLV-negative, PPD nonresponders (n = 11; NN); (ii) HTLV-negative, PPD responders (n = 18; NP); (iii) HTLV-positive, PPD nonresponders (n = 15; PN); and (iv) HTLV-positive, PPD responders (n = 15; PP). In vitro stimulation with PPD resulted in both proliferative responses and gamma interferon (IFN-gamma) production in NP and PP (P < 0.02), with minimal proliferation and IFN-gamma production in the NN and PN groups. Further, PPD-specific interleukin 10 (IL-10) production was significantly reduced in the PN group (P < 0.01), while the other groups had comparable levels. Cytokine reconstitution experiments demonstrated that while addition of recombinant IL-12 (rIL-12) plus anti-IL-4 restored PPD-specific responses in the NN group, it had no effect in the PN group. However, addition of rIL-12 resulted in the increased production of IFN-gamma in both nonresponder groups (NN and PN), suggesting that the lack of IFN-gamma production was not responsible for the PPD anergy. We conclude that PPD-specific anergy in HTLV-1-infected individuals appears to be due in part to their inability to respond to rIL-12.
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PMID:Modulation of T-cell responses to a recall antigen in human T-cell leukemia virus type 1-infected individuals. 1047 23

Leukaemia inhibitory factor (LIF) plays an important role as a haematopoietically active cytokine. As described earlier in a murine model, interleukin 1 (IL-1) induced LIF mRNA and protein expression. We utilized the murine cell line +/+-1.LDA11 to further define regulatory mechanisms of LIF expression in bone marrow stromal cells. The production of LIF mRNA is stimulated by IL-1beta, TNF-alpha, and the cAMP analogue 8-bromoadenosine 3':5'-monophosphate (8BrcAMP). LIF mRNA expression is controlled at the transcriptional level. Different fragments from -542 to -45 bp 5' upstream of the transcriptional start site of the murine LIF gene were fused to the luciferase gene. All LIF-promoter luciferase constructs exhibited constitutive luciferase activity under serum free conditions. The level of luciferase activity decreased with LIF-promoter constructs of less than 249 bp (pLIF249) in size. When tested with the 314 bp LIF-promoter construct, incubation of stromal cells with IL-1beta (500 U/ml) resulted in a 1.57-fold stimulation, with TNF-alpha (500 U/ml) in 2.06-fold stimulation, and with 8BrcAMP (0.5 mM) in a 3. 42-fold stimulation of luciferase activity. By testing different deletion mutants we could narrow the IL-1 and TNF-alpha responsive promoter areas to the region -249 to -145 bp and the 8BrcAMP responsive area from -145 to -82 bp. Mobility shift experiments revealed that nuclear proteins from stromal cells form a DNA-protein complex by binding to the region from -249 to -145 bp of the LIF promoter.
Cytokine 1999 Sep
PMID:Regulatory elements of the leukaemia inhibitory factor (LIF) promoter in murine bone marrow stromal cells. 1047 1

Cytokines such as granulocyte-macrophage colony-stimulating factor (GM-CSF) and IL-3 promote the survival and stimulate the proliferation of haematopoietic cells. Using the GM-CSF-dependent TF-1 myeloid leukaemia cell line, the authors show that the endogenous levels of BCL-2 and MCL-1 are downregulated upon GM-CSF withdrawal, whereas the levels of BCL-x(L)and Bax are unchanged. Re-exposure of growth factor deprived cells to GM-CSF resulted in an early and transient increase in MCL-1 expression, and prolonged induction of BCL-2, which prevented apoptosis. In contrast, the expression of BCL-2 and MCL-1 were not modulated during TPA-induced differentiation of TF-1 cells, which was followed by apoptosis despite the presence of GM-CSF. TF-1 cells overexpressing BCL-2 or MCL-1 underwent delayed apoptosis upon growth factor withdrawal, but displayed no impaired apoptosis in response to TPA. Erythropoietin (Epo) induced the expression of BCL-2 and MCL-1 protein in TF-1 cells, however it did not support their long term proliferation, further demonstrating that upregulation of these anti-apoptotic genes is insufficient for the long term proliferation of TF-1 cells.
Cytokine 1999 Nov
PMID:GM-CSF rescues TF-1 cells from growth factor withdrawal-induced, but not differentiation-induced apoptosis: the role of BCL-2 and MCL-1. 1054 72

Tumour necrosis factor alpha (TNF-alpha) inflammatory activity is mediated, at least in part, by prostaglandin E(2)(PGE(2)). In osteoarthritis (OA), other cytokines are believed to play a role by interacting with TNF-alpha. Using OA synovial fibroblasts, we investigated the effects of interleukin 8 (IL-8), leukaemia inhibitory factor (LIF) and IL-11 on the level of TNF-alpha-induced PGE(2), and their impact on the TNF-alpha-induced cellular signalling cascades including the TNF-receptor (TNF-R), soluble TNF-R (TNF-sR), cytoplasmic phospholipase A2 (cPLA2), cyclooxygenase 2 (COX-2), and the transcription factors NF-kappaB, C/EBP, CREB and AP-1.IL-8 increased in a synergistic manner (282% at 5 ng/ml) and LIF in an additive fashion (69% at 50 ng/ml) the TNF-alpha-induced PGE(2)release, while IL-11 reduced it (52% at 5 ng/ml). IL-8 (5 ng/ml) and LIF (50 ng/ml) alone upregulated (30%) the TNF-R binding level, but significantly downregulated the TNF-alpha-induced levels (P<0.007 and P<0.004, respectively) and the TNF-sR55 level. In contrast, IL-11 reduced the basal level by 18% (P<0.005) and the TNF-alpha-induced level of TNF-R by 51% (P<0.01) as well as decreasing both TNF-sR55 and TNF-sR75. The COX-2 synthesis level was increased by IL-8 and LIF under TNF-alpha treatment but downregulated by IL-11. IL-8 and LIF either alone or under TNF-alpha treatment increased the cPLA2 synthesis, while IL-11 decreased the level under both conditions. Interestingly, IL-8 induced in a synergistic manner and LIF in an additive fashion, the level of cPLA2 activity. IL-8 and LIF had no effect on the TNF-alpha-induced NF-kappaB accumulation, while IL-11 significantly decreased it (P<0. 02). All three cytokines inhibited TNF-alpha-induced C/EBP, but no true effect was noted for AP-1 and CREB in the presence of TNF-alpha. These results indicate that IL-8 synergizes and LIF potentiates the TNF-alpha PGE(2)effect which appears to be mediated mostly by increasing cPLA2 activity level. On the other hand, IL-11 alone had no effect on the PGE(2)release, but in conjunction with TNF-alpha, this cytokine showed anti-inflammatory properties. This study provides a rational foundation to develop therapeutic strategies for the treatment of OA by shedding light on the mechanisms of action of three prominent cytokines at work in articular joint tissues.
Cytokine 1999 Dec
PMID:Differential effects of IL-8, LIF (pro-inflammatory) and IL-11 (anti-inflammatory) on TNF-alpha-induced PGE(2)release and on signalling pathways in human OA synovial fibroblasts. 1062 27

We investigated both in vitro and ex vivo the role of mature osteoblasts (OB) and bone marrow stromal cells (BMSC) in RA and OA by analysing the expression of the following IL-6-type cytokines: IL-11, leukaemia inhibitory factor (LIF), oncostatin M (OSM) and IL-6. OB and BMSC were isolated from femora of RA, OA and post-traumatic (PT) patients, cultured in vitro in the presence or absence of IL-1beta and tumour necrosis factor-alpha (TNF-alpha), and assessed for the production and mRNA expression of IL-6-type cytokines. Trabecular bone biopsies were obtained from the inner portions of femoral heads and used for cytokine in situ immunostaining. Cultured OB and BMSC from different patients constitutively secreted IL-11 and IL-6 but not OSM. LIF was secreted only by BMSC, at very low levels. Interestingly, IL-11 basal production was significantly higher in BMSC than in OB in all three groups tested. IL-1beta and TNF-alpha strongly stimulated IL-6-type cytokine release (except for OSM) by both OB and BMSC. OSM was expressed only at mRNA levels in all groups studied. Cytokine immunostaining on bone biopsies confirmed the data obtained on cultured cells: IL-11, IL-6 and LIF proteins were detected both in mesenchymal (BMSC and OB) and mononuclear cells; OSM was found only in mononuclear cells. These data demonstrate that IL-6-type cytokines are constitutively expressed in the bone compartment in RA, OA and PT patients and can be secreted by bone cells at different stages of differentiation (BMSC and OB). This suggests that these cytokines may be involved in the mechanisms of bone remodelling in OA and RA.
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PMID:Osteoblasts and stromal cells isolated from femora in rheumatoid arthritis (RA) and osteoarthritis (OA) patients express IL-11, leukaemia inhibitory factor and oncostatin M. 1063 74

Over the past decade, the involvement of tyrosine kinases in signal transduction pathways evoked by cytokines has been intensively investigated. Only relatively recently have the roles of serine/threonine kinases in cytokine-induced signal transduction and anti-apoptotic pathways been examined. Cytokine receptors without intrinsic kinase activity such as interleukin-3 (IL-3), granulocyte-macrophage colony-stimulating factor (GM-CSF) and the interferons were thought to transmit their regulatory signals primarily by the receptor-associated Jak family of tyrosine kinases. This family of tyrosine kinases activates STAT transcription factors, which subsequently transduced their signals into the nucleus to modulate gene expression. Cytokine receptors with intrinsic tyrosine kinase activity such as c-Kit were initially thought to transduce their signals independently of serine/threonine kinase cascades. Recently, both of these types of receptor signaling pathways have been shown to interact with serine/threonine kinase pathways as maximal activation of these tyrosine kinase regulated cascades involve serine/threonine phosphorylation modulated by, for example MAP kinases. A common intermediate pathway initiating from cytokine receptors is the Ras/Raf/MEK/ERK (MAPK) cascade, which can result in the phosphorylation and activation of additional downstream kinases and transcription factors such as p90Rsk, CREB, Elk and Egr-1. Serine/threonine phosphorylation is also involved in the regulation of the apoptosis-controlling Bcl-2 protein, as certain phosphorylation events induced by cytokines such as IL-3 are anti-apoptotic, whereas other phosphorylation events triggered by chemotherapeutic drugs such as Paclitaxel are associated with cell death. Serine/threonine phosphorylation is implicated in the etiology of certain human cancers as constitutive serine phosphorylation of STATs 1 and 3 is observed in chronic lymphocytic leukemia and can be inhibited by the chemotherapeutic drug fludarabine. Serine/threonine phosphorylation also plays a role in the etiology of immunodeficiencies. Activated STAT5 proteins are detected in reduced levels in lymphocytes recovered from HIV-infected individuals and immunocompromised mice. Serine/threonine phosphorylation may be an important target of certain chemotherapeutic drugs which recognize the activated proteins. This meeting report and mini-review will discuss the interactions of serine/threonine kinases with signal transduction and apoptotic molecules and how some of these pathways can be controlled by chemotherapeutic drugs. Leukemia (2000) 14, 9-21.
Leukemia 2000 Jan
PMID:Serine/threonine phosphorylation in cytokine signal transduction. 1063 71

Oncostatin M (OSM) and leukaemia inhibitory factor (LIF) exhibit pleiotropic biological activities and share many structural and genetic features. The two cytokines bind with high affinity to the same receptor (LIF/OSM receptor), which consists of the LIF receptor alpha chain (LIFRalpha) and the signal transduction unit gp130. A soluble form of the beta chain of the receptor complex called soluble gp130 (sgp130) has been cloned. In this study, we sought to determine whether recombinant sgp130 or anti-gp130 Ab could attenuate the resorption of proteoglycans induced by OSM and LIF in articular cartilage explants. The results show that at high concentrations sgp130 is capable of attenuating both LIF and OSM mediated resorption. In contrast, anti-gp130 Ab selectively inhibited the stimulation of proteoglycan (PG) release by OSM, albeit minimally. The failure of anti-gp130 to attenuate LIF stimulated PG resorption may be due to the normal interaction of LIF with LIFRalpha and unfettered heterodimerization of LIFRalpha with gp130 in the presence of the antibody. The results indicate that sgp130 and anti-gp130 can modulate cartilage PG metabolism in vitro. Whether sgp130 may have therapeutic activity in models of arthritis or indeed in arthritic diseases remains to be determined.
Cytokine 2000 Feb
PMID:Soluble glycoprotein 130 (gp130) attenuates OSM- and LIF-induced cartilage proteoglycan catabolism. 1067

Leukaemia inhibitory factor (LIF) is a pleiotropic cytokine that is particularly involved in nephrogenesis and repair of the extracellular matrix. Transgenic mice overexpressing LIF have mesangial proliferative glomerulonephritis. Also, during local inflammatory reactions, such as kidney graft rejection or urinary tract infections, urinary LIF excretion is enhanced. The aim of the study therefore was to study LIF production by normal and inflammatory diseased kidneys (glomerulonephritis or graft rejection), maintained in short cultures. To determine the responsibility of the kidney itself in LIF synthesis, we measured LIF secretion into the culture supernatants of human mesangial or renal tubular epithelial cells. Fragments from diseased kidneys, whether grafts or not, released more LIF than normal human kidney fragments, mesangial or renal tubular epithelial cells. However, LIF production was delayed in renal transplants compared to glomerulonephritic samples taken from untreated patients. In every case, LIF production was enhanced by interleukin 1beta (IL-1beta) and inhibited by IL-4 or dexamethasone, except in two severe rejection episodes. So, LIF appeared to respond to pro- and anti-inflammatory stimuli, in vitro and in vivo. Considering its biological effects, LIF could play a role in inflammatory renal diseases.
Cytokine 2000 Mar
PMID:Renal synthesis of leukaemia inhibitory factor (LIF), under normal and inflammatory conditions. 1070 54

Immunological control of acute leukemia may be achieved after allogeneic transplant. Despite promising preliminary results, the impact of immunotherapy with interleukin-2 (r-IL-2) on patients with acute leukemia (AL), in first complete remission (CR1) remains unclear. We conducted a prospective multicenter randomized trial to compare outcome in patients with AL in CR1, treated with autologous bone marrow transplantation (BMT) with or without postgraft r-IL-2. One hundred and thirty patients with AL in CR1 (myeloblastic (AML): N = 78; lymphoblastic (ALL): N = 52) were randomized at time of BMT to receive (N = 65) or not (N = 65) r-IL-2. r-IL-2 (RU 49637 from Roussel Uclaf) was started after hematological recovery, as a five cycle regimen (12 M IU/m2/day continuous infusion on day 1-5, 15-17, 29-31,43-45 and 57-59). The two groups were balanced for patient and transplant characteristics. Analysis was based on an intent to treat. Thirty-eight (59%) of the 65 patients randomized into the study group started r-IL-2 at a median of sixty-eight days (23-140) after transplant and received 77% (16-100) of the scheduled dosage. They received a median of 120 x 10(6) IU/m2 (25-156) over 10 (3-13) days during a total median period of 56 (3-78) days. With a median follow-up of 7 years (5.4-8.1 years), 79 patients relapsed (study group: 43 (66%); control group: 36 (55%): p = NS). Survival and leukemia-free survival estimates were 33% (23-45) versus 43% (22-52) and 29% (19-41) versus 36% (24-51) respectively for study and control groups (all p = NS). These results show that leukemic control after autologous BMT is not increased by r-IL-2 therapy. Further studies should investigate more appropriate r-IL-2 schedules and the possibilities offered by better antigen recognition and activated effector cells.
Eur Cytokine Netw 2000 Mar
PMID:Randomized study of recombinant interleukin-2 after autologous bone marrow transplantation for acute leukemia in first complete remission. 1070 5

Leukaemia inhibitory factor (LIF) and interleukin-6 (IL-6) are candidate embryo-maternal signalling molecules which are present within the uterine luminal micro-environment. We examined the relative expression of the mRNAs encoding LIF and IL-6, as well as the LIF-binding subunit (LIFR-beta) of the LIF receptor and, as a potential downstream cytokine-responsive gene, beta(2)-microglobulin (beta(2)m), in porcine peri-implantation conceptuses, and in placenta and endometrium during early and mid-pregnancy. Peri-implantation spherical and filamentous conceptuses expressed LIFR-beta and beta(2)m mRNAs with no LIF mRNA present. Rapid development in days 11/12 spherical conceptuses to the filamentous stage was accompanied by transiently increased IL-6 gene expression. The corresponding endometrium, in contrast, expressed LIF in addition to these other mRNAs. LIFR-beta, IL-6 and beta(2)m, but not LIF mRNAs, were expressed in the Jag-1 cell line, an in vitro model for porcine day 14 trophoblast. The greatest steady-state amounts of LIF, LIFR-beta and IL-6 mRNAs in both the endometrium and placenta were evident at the post-implantation stages (days 30 and 60>day 18 of pregnancy). Treatment of porcine endometrial explants with human recombinant (hr)LIF or hrIL-6 resulted in no change in, or diminished, the presence of endometrial beta(2)m mRNA, respectively. Addition of LIF to peri-implantation conceptus explant cultures, in contrast, induced beta(2)m mRNA synthesis. These results highlight the potential importance of both the endometrium and placenta as sources, as well as targets, of these cytokines throughout pregnancy. Cytokine modulation of beta(2)m, a known in vitro mitogen, may constitute one mechanism for local control of trophoblast and endometrial proliferation.
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PMID:Pregnancy-dependent expression of leukaemia inhibitory factor (LIF), LIF receptor-beta and interleukin-6 (IL-6) messenger ribonucleic acids in the porcine female reproductive tract. 1083 69


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