Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P06889 (Mol)
 630,302 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The rat angiotensinogen gene is induced in the course of the hepatic acute-phase response. We demonstrate that monocyte conditioned medium can stimulate transcription of a stably introduced reporter construct driven by 615 base pairs of the angiotensinogen 5'-flanking sequence, as well as the endogenous gene, in Reuber H35 cells. Point mutations of a cis-acting element, located 545 base pairs from the transcription start site and sharing sequence identity with known nuclear factor kappa B (NF kappa B)-binding sites, led to loss of cytokine inducibility. When cloned upstream of a minimal promoter, this cis-acting element imparted transcriptional inducibility by monocyte conditioned medium, interleukin-1, and tumor necrosis factor on a luciferase reporter gene in HepG2 cells. Two distinct proteins bound this element in vitro: a heat-stable, constitutively present, hepatic nuclear protein that gave rise to a DNase I-protected footprint covering the functionally defined element; and a binding protein of different mobility, induced by monocyte conditioned medium, which also recognized the NF kappa B-binding site of the murine kappa light-chain enhancer. UV cross-linking showed this inducible protein to have an apparent molecular mass of 50 kilodaltons, similar to that described for NF kappa B and distinct from the constitutively present protein that was shown by Southwestern (DNA-protein) blot to have a molecular mass of 32 kilodaltons. Methylation interference analysis showed that the induced species made contact points with guanine residues in the NF kappa B consensus sequence typical of NF kappa B. Induction of this binding activity did not require new protein synthesis, and 12-O-tetradecanoylphorbol-13-acetate could mimic the induction by cytokines. We thus provide direct evidence for involvement of NF kappa B or a similar factor in the hepatic acute-phase response and discuss the potential role of the presence of a constitutive nuclear factor binding the same cis element.
Mol Cell Biol 1990 Mar
PMID:An inducible 50-kilodalton NF kappa B-like protein and a constitutive protein both bind the acute-phase response element of the angiotensinogen gene. 210 65

The interleukin-6 (IL-6) promoter is rapidly and transiently activated with other cytokines, including IL-1, tumor necrosis factor, and platelet-derived growth factor, as well as phorbol esters and agents that increase intracellular cyclic AMP. In this study, we have investigated cis-acting regulatory elements and trans-acting factors responsible for IL-1-induced IL-6 gene expression. Studies on the 5' deletion mutants of the human IL-6 gene suggested that the IL-1-responsive element was mapped within the IL-6 promoter region (-180 to -123) which was homologous to the c-fos serum-responsive enhancer element. Gel retardation assay identified two types of nuclear factors that bound to this region, one constitutive and the other inducible. These two factors recognized a 14-base-pair (bp) palindromic sequence, ACATTGCACAATCT. Furthermore, three copies of this 14-bp palindrome conferred IL-1 responsiveness to the basal enhancerless IL-6 promoter, indicating that a 14-bp-dyad symmetry sequence was an IL-1-responsive element in the IL-6 gene.
Mol Cell Biol 1990 Jun
PMID:Constitutive and interleukin-1 (IL-1)-inducible factors interact with the IL-1-responsive element in the IL-6 gene. 211 42

Intra-alveolar fibrin deposition accompanies many forms of inflammatory lung injury. Appropriate clearance of this fibrin matrix is important for normal healing and remodeling. The local generation of plasmin by the action of plasminogen activators (PAs) represents a pivotal step in the fibrinolytic process. To investigate whether the alveolar epithelium plays a role in the modulation of intra-alveolar fibrinolysis, we have studied PA regulation by rat pulmonary alveolar epithelial cells. We have found large quantities of PA activity both in conditioned media and cell lysates from epithelial monolayers in culture. Casein-plasminogen zymography reveals that this PA activity migrates as a tight doublet with an apparent mol wt of 45 kD, clearly distinct from rat tissue-type PA (tPA, greater than 68 kD). Analysis of freshly isolated type II alveolar epithelial cells demonstrates readily measurable PA activity in cell lysates, as well as expression of urokinase-type PA (uPA) mRNA on Northern blot analysis. Upregulation of PA activity occurs progressively with time in culture as the alveolar epithelial cells lose type II cell characteristics and become more flattened. Stimulation of alveolar epithelial cell monolayers with lipopolysaccharide or tumor necrosis factor increases levels of secreted PA activity. The relative abundance of uPA mRNA was shown to change in parallel with PA activity during in vitro differentiation or after exposure to inflammatory mediators. Thus, alveolar epithelial cells are likely an important source of uPA in the lung, the expression of which is influenced by the state of cellular differentiation as well as the presence of inflammatory mediators.(ABSTRACT TRUNCATED AT 250 WORDS)
Am J Respir Cell Mol Biol 1990 Nov
PMID:Expression of urokinase-type plasminogen activator by rat pulmonary alveolar epithelial cells. 212 Nov 71

The acute-phase response is a protective physiological reaction to tissue injury manifested by the immediate increase in production and secretion of liver proteins the function of which is to re-establish the homeostasis altered by injury. Such proteins include blood coagulation factors, opsonins, protease-inhibitors and angiotensinogen, a precursor of the potent vasopressor peptide angiotensin II. The angiotensinogen gene is typical of genes regulated during the acute-phase response inasmuch as the promoter regulating its transcription rate is acutely responsive to three known mediators of the acute-phase response: glucocorticoids, and the cytokines interleukin-1 and tumor necrosis factor. We present a model, based on experimental evidence, for the mechanism by which angiotensinogen gene transcription is regulated in a graded fashion by the interplay of several hormonally-inducible transcription factors that bind a hormonally-inducible enhancer unit of the angiotensinogen promoter. These factors include the glucocorticoid receptor, nuclear factor kappa B and members of the CAAT/viral enhancer (C/EBP) family of DNA-binding proteins.
Mol Cell Endocrinol 1990 Dec 21
PMID:Transcriptional regulation of hepatic angiotensinogen gene expression by the acute-phase response. 212 77

We monitored patients treated for 5 days with continuous infusion of increasing doses (3 to 6 x 10(6) U/d) of natural interleukin-2 (IL-2). CD16+, CD25+, and CD56+ cells increased after treatment. Plasma tumor necrosis factor-alpha (TNF-alpha) levels, but not interferon-gamma (IFN-gamma) levels, increased during IL-2 treatment, but spontaneous and IL-2-stimulated TNF-alpha secretion in vitro remained abnormally low. However, mitogen-stimulated TNF-alpha release was normal. Mitogen-stimulated, but not IL-2-stimulated, IFN-gamma release was strongly depressed. Low spontaneous and IL-2-stimulated cytotoxicity on K562 or Daudi increased after treatment. Low suppressor cell generation also normalized after treatment. This appears to be the first reported study of immunologic monitoring of cancer patients treated with natural rather than recombinant IL-2.
Mol Biother 1990 Mar
PMID:Lymphokine release, suppressor cell generation, cell surface markers, and cytotoxic activity in cancer patients receiving natural interleukin-2. 213 87

The presence of tumor necrosis factor type alpha (TNF-alpha) in different fetal tissue and adult adrenal extracts was investigated by radioimmunoassay (RIA). Measurable levels of TNF-alpha were found in 12/22 fetal adrenals, but in none of the seven adult adrenals studied. Since it is known that (i) steroidogenesis in fetal adrenals differs greatly from that in adult glands by having higher androgen/corticosteroid ratio, (ii) and that macrophage-derived factors may cause adrenocortical suppression, the effect of TNF-alpha on corticotropin-induced steroidogenesis in primary cultures of human fetal adrenals was studied. Results show that TNF-alpha effectively suppresses the production of cortisol and shifts the steroid synthesis towards androgen production. The effect was not accompanied by any change in cell viability and could be neutralized by addition of polyclonal rabbit anti-TNF-alpha antiserum to cell cultures. These results suggest that TNF-alpha may take part in the regulation of human fetal steroidogenesis within the network of the fetoplacental unit via inhibition of the cortisol synthesis.
Mol Cell Endocrinol 1990 Jan 22
PMID:Regulation of ACTH-induced steroidogenesis in human fetal adrenals by rTNF-alpha. 215 34

As an approach to isolate the cell-surface receptor for tumor necrosis factor (TNF), we have developed transfectants of human B-lymphoblastoid cells (UC cells) that overexpress the TNF receptor. These transfectants were isolated from UC cells transfected with cDNA libraries of HeLa or NG108 cells constructed in the mammalian expression vector EBO-pcD. This vector contains the Epstein-Barr virus origin of replication (ori-P) plus the EBNA-1 gene conferring replication function to ori-P and, therefore, the ability to replicate autonomously within the transfected cell (Margolskee, R.F., Kavathas, P., and Berg, P. (1988) Mol. Cell. Biol. 8, 2837-2947). Cells overexpressing the TNF receptor were identified and separated by the binding of fluoresceinated TNF and flow cytometric selection. Scatchard analysis of 125I-TNF binding data revealed a single class of high affinity receptors with a dissociation constant (Kd) of 0.2 to 2 nM and a receptor density of about 150,000 per cell, an increase of approximately 150-fold over UC cells. Cross-linking of receptor-ligand with bis-sulfosuccinimidyl suberate followed by polyacrylamide gel electrophoresis gave estimates of 87 and 104 kDa for the size of the complex. Based on its ability to bind TNF, a 68-kDa receptor protein was identified in cell extracts enriched for the receptor by using immobilized wheat germ agglutinin and TNF affinity chromatography. The difference in the estimated size of the receptor and the receptor-ligand complexes demonstrates that TNF binds to the receptor as a monomer or a dimer. Analysis of cDNA sequences conferring receptor amplification in transfectants revealed that plasmid DNA was present at 30 or more copies per cell, most likely integrated into the genomic DNA or organized into high molecular weight catenanes, and autonomously replicating units could not be recovered. Therefore, while this vector was useful in generating stable receptor-amplified cells, it was not maintained as a recoverable episome.
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PMID:Amplified expression of tumor necrosis factor receptor in cells transfected with Epstein-Barr virus shuttle vector cDNA libraries. 215 25

Studies have suggested that recombinant tumor necrosis factor-alpha (TNF-alpha) may potentiate the killing of murine tumor cells by drugs targeted at DNA topoisomerase II. We have examined the combined cytotoxic effects of the topoisomerase-targeted drug etoposide and TNF in small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC) cell lines using clonogenic assays and a novel flow cytometry technique relying on differential uptake of fluorescein diacetate (FDA) and propidium iodide (PI) by viable and nonviable cells. Good correlation of IC50 determinations for etoposide were noted between clonogenic assays and the FDA/PI technique for both classic and variant SCLC cell lines. The effects of etoposide on the classic SCLC line H209 were potentiated by TNF with a decrease in the IC50 from 3.3 microM to 1.0 microM as determined by FDA/PI. Tumor necrosis factor alone had little effect on the growth or cloning efficiency of H209 cells. Tumor necrosis factor alone stimulated the growth and cloning of variant SCLC line N417, but the cytotoxicity of etoposide was not potentiated by TNF in N417 cells. Tumor necrosis factor alone inhibited the growth and cloning of the NSCLC line H125 but exerted a marked protective effect against higher concentrations of etoposide. It appears that the interaction of TNF with etoposide varies between cell lines and between subclasses of human lung cancer.
Mol Biother 1990 Sep
PMID:Interaction of recombinant human tumor necrosis factor and etoposide in human lung cancer cell lines. 217 61

si e s------------------------ABSTRACT------------------------- P4 initiates specifically the degradation of interstitial collagen types I-III. This enzyme is thus directly involved in the remodeling of the connective matrix. Fibroblasts are considered as the major source of interstitial collagenase in many tissues. However previous studies shown that liver fibroblasts did not spontaneously produce the enzyme. We have thus measured the steady-state levels of mRNA for interstitial procollagenase and quantified interstitial collagenase activity in cultured human liver fibroblasts, in presence or not of interleukin-1 or tumor necrosis factor. We demonstrate that human liver fibroblasts have the capacity for producing interstitial collagenase and that this production is regulated at a transcriptional step. We suggest that the liver fibroblast could represent a key cell for therapeutic strategies of fibrosis reversal.
Cell Mol Biol 1990
PMID:Human liver fibroblast capacity for synthesizing interstitial collagenase in vitro. 217 78

The alveolar macrophage (AMO) in its pivotal position for pulmonary host defense may play a prominent role in the orchestration of polymorphonuclear leukocyte (PMN) diapedesis. We demonstrate that the human AMO may participate in these inflammatory events through the production of a novel neutrophil chemotactic factor, interleukin-8 (IL-8). The induction of AMO-derived IL-8 by tumor necrosis factor (TNF), lipopolysaccharide (LPS), and interleukin-1 (IL-1 beta) was shown to be both dose and time dependent. Maximal IL-8 gene expression, as assessed by Northern blot analyses, was achieved with 20 ng/ml and 1 microgram/ml, respectively, for each of the cytokines and LPS. A kinetic study of TNF-, IL-1 beta-, and LPS-treated AMOs showed significant steady-state IL-8 mRNA accumulation post-stimulation at 1 h, peaking by 8 h, with a decline over the next 16 h. Immunohistochemical staining using rabbit anti-human IL-8 antibody demonstrated significant immunolocalization of cell-associated IL-8 antigen at 4 h, with persistence over the next 20 h. Chemotactic bioactivity peaked by 8 h, with continued production over the next 16 h. Chemotactic bioactivity from AMO-conditioned media was inhibited by IL-8 antiserum by 2, 31, 44, and 47%, respectively, for unstimulated control, LPS-, IL-1 beta-, and TNF-treated cells. Preimmune serum had no effect on chemotactic activity. These data support the central role of the AMO in the elicitation of PMNs into the lung via the production of IL-8.
Am J Respir Cell Mol Biol 1990 Apr
PMID:Human alveolar macrophage gene expression of interleukin-8 by tumor necrosis factor-alpha, lipopolysaccharide, and interleukin-1 beta. 218 81


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