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)

We have examined the effects of tumor necrosis factor alpha (TNF) and lymphotoxin (LT) on gelatinase (72 kDa and 92 kDa) and tissue inhibitor of metalloprotease 1 (TIMP1) secretion by human myeloblastic leukemia cells (ML-1) in vitro. TNF (0.1-30 ng/ml) significantly stimulated 92 kDa gelatinase secretion in a dose-dependent manner, but did not significantly stimulate 72 kDa gelatinase secretion. LT also significantly stimulated 92 kDa gelatinase secretion, but the stimulation was less effective compared to TNF. TNF, but not LT, concentrations at 30 ng/ml slightly stimulated TIMP1 secretion. Because 92 kDa gelatinase is thought to play a pivotal role in tumor invasion, we examined the effect of TNF or LT on ML-1 cell invasion through a reconstituted basement membrane (Matrigel). Exposure of ML-1 cells to TNF (3, 10, and 30 ng/ml) or LT (3, 10, and 30 ng/ml) stimulated ML-1 cell invasion through Matrigel in a dose-dependent manner in vitro. The data suggest that TNF- and LT-stimulated 92 kDa gelatinase secretion could play an important role in TNF- or LT-stimulated ML-1 cell invasion.
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PMID:Tumor necrosis factor alpha and lymphotoxin stimulate human myeloblastic leukemia cell (ML-1) invasion through a reconstituted basement membrane (Matrigel) with concomitant induction of 92 kDa gelatinase secretion. 855 14

Phenylphthalimides (2-phenyl-1H-isoindole-1,3-diones) were prepared and their effects on tumor necrosis factor alpha (TNF-alpha) production by human leukemia cell line HL-60 stimulated with 12-O-tetradecanoylphorbol-13-acetate (TPA) were examined. An analysis of the structure-activity relationships of the phenylphthalimides indicated that potent enhancing activity on TPA-induced TNF-alpha production by HL-60 cells requires medium-sized substituent(s) at the ortho position(s) of the phenyl group; 2-(2,6-diisopropylphenyl)-1H-isoindole-1,3-dione (PP-33) increased the TNF-alpha production to more than 600% at the concentration of 1 x 10(-5) M. Introduction of a nitro group at the phthalimide moiety of PP-33 enhanced the activity; 2-(2,6-diisopropylphenyl)-4-nitro-1H-isoindole-1,3-dione (4NPP-33) and its 5-nitro isomer (5NPP-33) enhanced the TNF-alpha production to more than 800% and 700%, respectively, at the concentration of 1 x 10(-5) M. Introduction of fluorines into the phthalimide moiety of PP-33 greatly lowered the concentration of the compound necessary to elicit the TNF-alpha production-enhancing activity; 2-(2,6-diisopropylphenyl)-4,5,6,7-tetrafluoro-1H-isoindole-1,3-dio ne (FPP-33) showed the activity at nanomolar concentration, with the optimum concentration of 1 x 10(-7) M.
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PMID:Phenylphthalimides with tumor necrosis factor alpha production-enhancing activity. 858 37

Human immunodeficiency virus (HIV) 1 transgenic mice expressing low or undetectable levels of viral mRNA in lymphoid tissue were infected with the intracellular protozoan Toxoplasma gondii. Exposure to this parasite resulted in an increase in HIV-1 transcript in lymph nodes, spleens, and lungs during the acute phase of infection and in the central nervous system during the chronic stage of disease. In vivo and ex vivo experiments identified macrophages as a major source of the induced HIV-1 transcripts. In contrast, T. gondii infection failed to stimulate HIV-1 transcription in tissues of two HIV-1 transgenic mouse strains harboring a HIV-1 proviral DNA in which the nuclear factor (NF) kappa B binding motifs from the viral long terminal repeats had been replaced with a duplicated Moloney murine leukemia virus core enhancer. A role for NF-kappaB in the activation of the HIV-1 by T. gondii was also suggested by the simultaneous induction of NF-kappaB binding activity and tumor necrosis factor alpha synthesis in transgenic mouse macrophages stimulated by exposure to parasite extracts. These results demonstrate the potential of an opportunistic pathogen to induce HIV-1 transcription in vivo and suggest a mechanism for the in vivo dissemination of HIV-1 by macrophages.
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PMID:Infection of human immunodeficiency virus 1 transgenic mice with Toxoplasma gondii stimulates proviral transcription in macrophages in vivo. 866 22

In normal adult mammals, blood cell production, hemopoiesis, takes place within the medullary cavity. There, hemopoietic cell proliferation and differentiation are regulated by a network of stromal/accessory cells and their products (ie cytokines and extracellular matrix molecules), known as the hemopoietic microenvironment. Recent in vitro studies indicate that both cell composition and functional abnormalities of the hemopoletic microenvironment are present in a proportion of patients with myeloid leukemia, both chronic (CML) and acute (AML). Cell composition abnormalities have been primarily observed in a subset of patients with AML; these abnormalities include reduced numbers of fibroblast progenitors and, in some cases, reduced numbers of macrophages and adipocytes. In terms of function, it has been shown that the marrow stromal cells from a significant number of both CML and AML patients, possess a deficient hemopoletic supportive capacity in vitro. This seems to be related to the presence of functionally abnormal, malignant macrophages. The mechanisms by which these macrophages alter the hemopoietic function of the marrow stroma, as a whole, are still not fully understood. Whereas in AML, a macrophage-derived soluble inhibitory activity (containing tumor necrosis factor alpha) has been described; in CML, a direct, macrophage-mediated cell-to-cell contact mechanism for hemopoietic inhibition seems to be involved. To date, however, it is not clear whether the abnormalities in the hemopoietic microenvironment are secondary to myeloid leukemia or if they precede clinical CML/AML. Furthermore, it is not known to what extent the functional abnormalities observed in vitro contribute to the hematologic dysfunction that characterizes myeloid leukemia and to the in vivo progression of the disease.
Leukemia 1996 Jun
PMID:Composition and function of the hemopoietic microenvironment in human myeloid leukemia. 866 39

Blast cells derived from patients with acute myelogenous leukemia (AML) were cultured in the presence of interleukin-13 (IL-13). IL-13 did not cause statistically significant alterations of AML blast proliferation when cells were cultured in medium alone or together with IL-4, granulocyte colony-stimulating factor and granulocyte-macrophage colony-stimulating factor. In contrast, IL-13 inhibited constitutive AML blast secretion of IL-1 alpha, IL-1 beta, IL-6, tumor necrosis factor alpha, granulocyte colony-stimulating factor and granulocyte-macrophage colony-stimulating factor. IL-4 caused a similar inhibition of constitutive cytokine secretion as IL-13, but IL-13 caused no additive inhibition in the presence of IL-4. In contrast to IL-4 which increased AML blast release of IL-1 receptor antagonist, IL-13 caused no significant alteration of blast release of the receptor antagonist. IL-13 inhibited cytokine secretion also in the presence of neutralizing IL-4 and IL-10 antibodies and when AML blasts were cultures in serum-free conditions. We conclude that IL-13 has a direct and nontoxic inhibitory effect on constitutive AML blast cytokine secretion.
Leukemia 1996 Sep
PMID:Effects of interleukin-13 on cytokine secretion by human acute myelogenous leukemia blasts. 875 69

Human T-cell lymphotropic virus type I (HTLV-I) is known to cause adult T-cell leukemia/T-cell lymphoma and tropical spastic paraparesis/HTLV-I-associated myelopathy. Recent seroepidemiologic, clinical, and virologic studies indicate that the virus is also related to a certain type of uveitis, which has been classified as uveitis without defined etiologies or idiopathic uveitis. According to the seroepidemiologic survey, the seroprevalence of HTLV-I in patients with idiopathic uveitis was significantly higher than that of two control groups, that is, patients with uveitis with defined etiologies and patients with nonuveitic ocular diseases. Clinically, the uveitis seen in HTLV-I carriers is characterized by moderate to severe cellular infiltration in the eye and by moderate retinal vasculitis, and the intraocular inflammation responds well to corticosteroid therapy. Interestingly, 25% of female patients with the disease had a previous history of Graves disease with hyperthyroidisms. The following virologic, molecular biologic findings suggest that cytokines produced by HTLV-I-infected T cells in the eye play the central role in the pathogenic mechanisms of the uveitis: (a) the virus load in the peripheral blood monocytes analyzed by the quantitative polymerase chain reaction methods was significantly greater in patients with the uveitis than in asymptomatic carriers, (b) the proviral DNA of HTLV-I and the gene expression of the virus at the mRNA level was detected in the infiltrating cells from the eyes of the patients, (c) the virus particles were detected by electron-microscopic examination in the T-cell clones established from the intraocular fluid of the patients, and (d) the HTLV-I-infected T cells produced a variety of cytokines without any stimuli, such as interleukin (IL)-1 alpha, IL-2, IL-3, IL-6, IL-8, IL-10, tumor necrosis factor alpha, interferon-gamma, and granulocyte-macrophage colony-stimulating factor. Based on the seroepidemiologic, clinical, and virologic data, the uveitis seen in HTLV-I carriers is considered to be a distinct clinical entity related to HTLV-I infection, and the disease is designated as HTLV-I uveitis.
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PMID:HTLV-I uveitis. 879 4

N(alpha)-Phthalimidoglutarimide (thalidomide), 2-(2,6-diisopropylphenyl)-1H-isoindole-1,3-dione (PP-33) and its 4,5,6,7-tetrafluoro derivative (FPP-33) augmented 12-O-tetradecanoylphorbol 13-acetate-induced production by human leukemia HL-60 cells of both tumor necrosis factor alpha (TNF-alpha) mRNA and secreted TNF-alpha protein. Intracellular TNF-alpha protein production was increased to a lesser extent.
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PMID:Augmentation by phthalimides of phorbol ester-induced expression of tumor necrosis factor alpha message. 883 78

A poorly defined transforming event(s) affects the pluripotential bone marrow (BM) stem cell in myelodysplastic syndromes (MDS), conferring a growth advantage upon it which leads eventually to monoclonal hematopoiesis. The progeny of this transformed ancestor undergo recognizable albeit dysplastic maturation. We propose that this picture is further complicated by a variety of cytokines, tumor necrosis factor alpha (TNF-alpha), transforming growth factor beta (TGF-beta) and interleukin 1beta (IL-1beta) which exert a dual effect on the diseased cells. The immature CD34+ cells are stimulated to proliferate, while their later differentiated daughters are induced to undergo apoptosis accounting for the clinical syndrome of pancytopenia despite hypercellular BMs. Studies directed at measuring the rates of proliferation and apoptosis as well as the levels of TNF-alpha, TGF-beta and IL-1beta confirm this hypothesis and are presented in greater detail. A novel approach towards MDS therapy emerges as a result of this paradigm shift based upon the premise that anti-cytokine therapy would prevent excessive intramedullary apoptosis and result in improved cytopenias as well as cause a slowing down of the diseased precursor cell proliferation resulting in resumption of polyclonal hematopoiesis. Because a number of cytokines function through common lipid second messengers, interruption of this pathway should theoretically cause disruption in the signalling of a cascade of cytokines.
Leukemia 1996 Oct
PMID:A paradigm shift in myelodysplastic syndromes. 884

The expression of c-ets2 is rapidly induced in a variety of myelomonocytic cell lines as they differentiate into macrophages. We find that constitutive expression of c-ets2 in the M1D+ myeloblast leukemic cell line (M1ets2) is sufficient to push these cells to a more differentiated state. The expression of several differentiation-specific genes is upregulated in M1ets2 cells, including those encoding macrophage-specific lysozyme M and tumor necrosis factor alpha, which are involved in bacteriolytic and inflammatory processes, respectively. Transcription factors c-jun and junB, previously shown to induce partial macrophage differentiation when overexpressed in myelomonocytic leukemia cell lines, are also upregulated in M1ets2 cells. The upregulation of junB is the result of a direct interaction of Ets2 with ets binding sites of the junB promoter, since transient or constitutive Ets2 expression in M1D+ cells activates junB transcription via ets binding sites. In addition, transfection of a dominant negative mutant of Ets2, devoid of its transcriptional activation domain, greatly reduces transcriptional activities of the junB promoter in M1ets2 cells. Finally, unlike their parental M1D+ counterparts, M1ets2 cells secrete the macrophage colony-stimulating factor, CSF-1, and are able to phagocytize. Taken together, these results show that when the immature myeloid M1D+ cell line constitutively expresses c-ets2, these cells acquire different functions of mature macrophages.
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PMID:Constitutive c-ets2 expression in M1D+ myeloblast leukemic cells induces their differentiation to macrophages. 894 40

The objective of the present study was to investigate the interactions of 2-chlorodeoxyadenosine (2-CdA) with interferon alpha or gamma (IFN-alpha, IFN-gamma), as well as between 2-CdA and recombinant human tumor necrosis factor alpha (rhTNF-alpha), on the clonal growth of granulocyte-macrophage progenitor cells (CFU-GM) from patients with chronic myeloid leukemia (CML) and on clonogenic leukemia blasts (CFU-L) from acute myeloid leukemia (AML) patients. Progenitor cell culture in semisolid medium in vitro was applied and the percentage of colony growth inhibition was evaluated. The use of 2-CdA either with IFN-alpha or IFN-gamma and 2-CdA with TNF-alpha was found to inhibit, in a dose dependent manner, the growth of colonies formed by hematopoietic precursor cells from CML and AML patients as well as from normal individuals, with the greatest effect being observed after the use of 2-CdA and IFN-alpha at their highest concentrations.
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PMID:Interaction of 2-chlorodeoxyadenosine in combination either with interferons or recombinant human tumor necrosis factor alpha on myeloid progenitor cells in vitro. 901 67


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