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 effects of fluorouracil (5-FU) and interferon-gamma (IFN-gamma) on the regulation of thymidylate synthase (TS) gene expression were investigated in the human colon cancer H630 cell line. By Western immunoblot analysis, TS protein levels in H630 cells were increased 3-, 5.5-, 5-, and 2.5-fold after 8-, 16-, 24-, and 36-hr exposure to 1 microM 5-FU, respectively. When H630 cells were exposed to varying concentrations of 5-FU (0.3-10 microM) for 24 hr, increases in TS protein up to 5.5-fold were observed. A 24-hr exposure to 1 microM 5-FU resulted in a 4.5-fold increase in the level of TS protein, whereas in 5-FU/IFN-gamma-treated cells TS protein was increased by only 1.8-fold, compared with control cells. IFN-gamma treatment alone did not affect TS protein levels, relative to control. Northern blot analysis revealed no changes in TS mRNA levels when H630 cells were exposed either to 1 microM 5-FU for 8-36 hr, to varying concentrations of 5-FU (0.3-10 microM) for 24 hr, or to the combination of 5-FU and IFN-gamma. Pulse-labeling studies with [35S]methionine demonstrated a 3.5-fold increase in net synthesis of TS in cells treated with 1 microM 5-FU, whereas the level of newly synthesized TS increased only 1.5-fold in cells treated with 5-FU/IFN-gamma, compared with control cells. Pulse-chase studies revealed that the half-lives of TS protein in control and 5-FU-treated cells were equivalent. These findings demonstrate that the increase in TS protein after 5-FU exposure and the subsequent inhibitory effect of IFN-gamma on TS protein expression are both regulated at the post-transcriptional level.
Mol Pharmacol 1993 Apr
PMID:Regulation of thymidylate synthase in human colon cancer cells treated with 5-fluorouracil and interferon-gamma. 847 31

Fibroblasts may play an important role in the modulation of immune and inflammatory responses through elaboration of cytokines. To test this hypothesis, human lung fibroblasts were isolated from transbronchial biopsy specimens and assayed for production of interleukin-6 (IL-6) and granulocyte/macrophage colony-stimulating factor (GM-CSF). The sources of fibroblasts included lung allografts, recipient lungs obtained at time of transplant, and normal lung tissue removed during tumor resection. During the course of these studies, several early-passage fibroblasts from transplant recipients were observed to contain mycoplasma (MP)-like organisms as detected by extranuclear fluorescent staining with Hoechst 33258. Positive staining cultures were associated with isolation of Mycoplasma fermentans. IL-6 and GM-GSF as measured by ELISA were found to be elevated over 50-fold in conditioned medium from MP-infected fibroblasts as compared with noninfected lines. Treatment of cells with mycoplasma removal agent (MRA) eliminated extranuclear Hoechst fluorescence and significantly reduced the production of these cytokines. Tumor necrosis factor-beta (TNF-beta) induction of IL-6 and GM-CSF was amplified synergistically in infected cultures. No additional production of IL-6 or GM-CSF was observed in infected cultures treated with interferon-gamma (IFN-gamma) despite the ability of IFN-gamma to modestly induce IL-6 in uninfected cultures. Thus, in vitro infection of lung fibroblasts with MP represents a potent stimulus for the production of inflammatory cytokines and, therefore, necessitates rigorous control for these organisms in cell culture studies.(ABSTRACT TRUNCATED AT 250 WORDS)
Am J Respir Cell Mol Biol 1993 Apr
PMID:Enhanced secretion of immune-modulating cytokines by human lung fibroblasts during in vitro infection with Mycoplasma fermentans. 847 29

Chronic graft-versus-host disease (GVHD) can be induced in B6D2F1 mice by injection of parental DBA/2 lymphoid cells. Stimulation of donor T cells by host MHC antigens leads to the stimulation of host B cells. Little is known of the lymphokines produced during such a reaction. This study was designed to directly measure the levels of mRNA for interferon-gamma (IFN-gamma), interleukin 2 (IL-2), IL-4, IL-5, and IL-10, as well as several other genes, using semiquantitative polymerase chain reaction (PCR). Semiquantitative PCR was reproducible and signals generated were dependent on the amount of specific RNA or cDNA in each reaction. Early during the progression of GVHD (2 days after the first injection of parental cells) there was little increase in IL-10 mRNA, a slight increase in IL-4 mRNA, and a dramatic increase in IL-2 mRNA. In addition, IL-2 bioactivity was demonstrated in supernatants from GVH splenocytes cultured in vitro for 24 h. Later in the response (1 week after the second and final injection of parental cells) IL-4 mRNA levels were elevated as they were earlier while IL-10 mRNA levels were dramatically increased. IL-2 mRNA levels were no different in mice undergoing GVHD than in normal mice at this time. IFN-gamma mRNA was detectable both early and late, although at similar levels in normal mice and mice undergoing GVHD. At both times examined, IL-4 was below the limits of detection by bioassay and IFN-gamma, IL-4, IL-5 and IL-10 were below the limits of detection by ELISA. Further studies showed that a majority of the IL-4 and IL-10 mRNA found elevated in GVH mice were produced by Thy1.2+ T cells, with small amounts from B220+ B cells. In addition, the detectable IFN-gamma mRNA found in GVH mice at this later time also was produced by Thy1.2+ T cells, with small amounts from B220+ B cells.
Mol Immunol 1993 May
PMID:Cytokine gene expression in mice undergoing chronic graft-versus-host disease. 848 82

The cell surface expression of the CD32 receptors for the Fc portion of immunoglobulin G (Fc gamma RII-CD32) is regulated by agents such as phorbol esters (PMA) and cytokines. In this study, we investigated the effects of PMA and interferon-gamma (IFN-gamma) on the expression of CD32C mRNA in U937 cells. When U937 (CD32+) cells are incubated with either PMA or IFN-gamma a significant enhancement of CD32C mRNA expression is observed with maximum enhancement at 18 hrs post-PMA and IFN-gamma addition. The addition of actinomycin D (ActD), a transcriptional inhibitor, together with either PMA or IFN-gamma diminishes the enhanced levels of CD32C mRNA to the basal levels, indicating that transcriptional regulation is involved in this modulatory process. The addition of cyclohexamide (CX), a protein synthesis inhibitor, to cultures undergoing stimulation with either PMA or IFN-gamma, increased the levels of CD32C mRNA synthesis suggesting that regulatory degradation proteins may be involved. The PMA and IFN-gamma stimulated CD32C mRNA is degraded within 2 hr post-stimulation and this degradation is delayed by the inhibition of de novo protein synthesis. These results, taken together with our previous studies of CD32A mRNA regulation in U937 cells stimulated with PMA, indicate that both the CD32A and C isomer mRNAs are rapidly degraded; however, CD32A and C isomer mRNAs are differentially regulated. At the optimal PMA dose, the time of mRNA stimulation of CD32A and C mRNA varies and the addition of CX to U937 cells together with PMA enhanced the levels of CD32C mRNA but had no effect on CD32A mRNA levels. These results imply that the differential regulation of the two CD32 isomers may result in differential function.
Mol Immunol 1993 Jun
PMID:CD32C (Fc gamma RIIC) mRNA expression and regulation. 850 44

Lipopolysaccharide (LPS) treatment results in widespread expression of the inducible isoform of nitric oxide (NO) synthase (iNOS). Although there is evidence for the expression of iNOS in heart tissue, regulation of myocardial iNOS expression is not known. To determine the time course and degree of iNOS induction in the adult heart, we examined iNOS mRNA expression and enzyme activity in (1) rat left ventricular tissue after LPS treatment in vivo, and (2) cultured, long-term rat cardiac myocytes maintained in serum and exposed to interleukin-1 beta, tumor necrosis factor-alpha, interferon-gamma, and/or LPS. iNOS mRNA was detected by Northern blot analysis and in situ hybridization. iNOS enzyme activity was measured in extracts of whole heart, and nitrate and nitrite (the stable end-products of NO) accumulation was quantified in cardiomyocyte culture media. iNOS mRNA was not detected in untreated hearts or cultured myocytes but was apparent within 3 h in both hearts obtained from LPS-treated animals and in cytokine-treated myocytes. In whole heart, iNOS mRNA expression peaked by 6 h after LPS and declined by 12 and 24 h. In situ hybridization demonstrated perinuclear localization of iNOS mRNA in both cardiac vascular smooth muscle and myocytes with maximal expression at 6 h after LPS injection. In cardiac myocytes, iNOS expression was maximal at 12 to 24 h, persisted through 48 h, and was partially inhibited by dexamethasone. Interferon-gamma was the most potent single cytokine with regards to myocyte iNOS induction. Nitric oxide release in cytokine-stimulated cardiac myocytes was largely in the form of nitrate and was associated with increased glucose uptake and lactate release; the former finding indicates that NO interacts with myocardial heme proteins and/or oxyradicals, while the latter suggests inhibition of oxidative metabolism. Although non-myocardial cells may significantly contribute to iNOS expression in whole heart tissue, significant iNOS expression and NO production also take place within the myocyte. Induced NO production may regulate myocardial perfusion and impair myocardial function and metabolism.
J Mol Cell Cardiol 1995 Sep
PMID:Characterization of inducible nitric oxide synthase expression in endotoxemic rat cardiac myocytes in vivo and following cytokine exposure in vitro. 852 61

Sensitization of BALB/c mice to ovalbumin (OVA) through the airways stimulated allergen-specific immediate hypersensitivity responses and these effects were related to the expansion of V beta 8.1/8.2+ T cells. In contrast, splenic V beta 2+ T cells from sensitized animals inhibited V beta 8.1/8.2+ T-cell induction of anti-OVA IgE production in vivo. To examine whether such differences in T-cell function were associated with differences in cytokine production, CD4+ T cells and CD4+ T cells depleted of V beta 8.1/8.2+ T cells were analyzed for interleukin-4 (IL-4) and interferon-gamma (IFN-gamma) production. In nonsensitized animals, no differences in IL-4 and IFN-gamma production were found in mRNA levels as well as in protein levels in these two populations of cells. In contrast, CD4+ T cells from sensitized mice showed higher IL-4 and lower IFN-gamma production than CD4+ cells depleted of V beta 8+ lymphocytes. Similar results were obtained after stimulation of CD4+ T cells from OVA-sensitized animals with anti-V beta 2 and anti-V beta 8.1/8.2 antibodies. Stimulation of V beta 8.1/8.2+ T cells from sensitized mice with OVA or OVA peptide 323-339 also resulted in increased production of IL-4. These data indicate that allergen sensitization via the airways stimulates the selective expansion of certain V beta-expressing T cells and that these T-cell subsets exhibit different functional activities in terms of cytokine production.
Am J Respir Cell Mol Biol 1996 Jan
PMID:Production of interleukin-4 and interferon-gamma by TCR-V beta-expressing T-cell subsets in allergen-sensitized mice. 853 84

We investigated the cytotoxic effects of various cytokines secreted by macrophages or T lymphocytes on luteal cells, and the role of nitric oxide (NO) produced by luteal cells in cytotoxic actions of cytokines. Mouse luteal cells were cultured in serum-free medium with interferon-gamma (IFN-gamma), tumor necrosis factor-alpha (TNF-alpha) or interleukin-1 beta (IL-1 beta) alone, or with various combinations of these cytokines for 6 days. Cytotoxic actions of cytokines and NO production by luteal cells were evaluated by number of viable cells and the amount of nitrite and nitrate (stable metabolites of NO) in medium, respectively. IFN-gamma (1000 U/ml), TNF-alpha (3000 U/ml), or IL-1 beta (30 U/ml) alone, and the combination of TFN-alpha and IL-1 beta (10 U/ml) did not decrease number of viable cells and was without effects on NO production. The combination of IFN-gamma and IL-1 beta (10 U/ml) also did not decrease the number of viable cells, while it increased NO production a little but significantly. Combinations of INF-gamma and TNF-alpha, and IFN-gamma, TNF-alpha and IL-1 beta (10 U/ml) markedly decreased number of viable cells. The combination of IFN-gamma and TNF-alpha increased NO production a little but significantly, and the combination of three cytokines (IFN-gamma, TNF-alpha, and IL-1 beta) caused a greater increase in NO production. An NO synthase inhibitor, L-NG-monomethy-L-arginine (0.5 mM) or aminoguanidine (0.5 mM) abolished increases in NO production induced by combinations of IFN-gamma and TNF-alpha, and IFN-gamma, TNF-alpha and IL-1 beta completely without effects on number of viable cells. The present results indicate that combinations of cytokines including IFN-gamma and TNF-alpha induce death of cultured mouse luteal cells, and that the cytotoxic actions of these cytokines are independent of NO production by luteal cells.
J Steroid Biochem Mol Biol 1995 Dec
PMID:Cytotoxic actions of cytokines on cultured mouse luteal cells are independent of nitric oxide. 854 Dec 25

It has been suggested that the thyroid itself may contribute to the inflammatory process observed in autoimmune thyroiditis by releasing the cytokines interleukin-1 alpha (IL-1 alpha), interleukin-6 (IL-6) and interleukin-8 (IL-8), but studies of cytokine gene expression in thyrocytes have been limited and conflicting. A semi-quantitative reverse transcription-PCR technique has been used to investigate the expression of IL-1 alpha, IL-6 and IL-8 mRNA in the human thyroid cell line HTori3 and in cultures of primary human thyroid follicular cells (TFCs). Cytokine mRNA levels were examined over a 24-h period, and the modulatory effects of exogenous IL-1 alpha, interferon-gamma (IFN-gamma) and TSH investigated. Basal expression of IL-1 alpha, IL-6 and IL-8 mRNA was detected in HTori3 and primary TFC cultures. Stimulation with IL-1 (10 U/ml) for 12 h produced an increase in the level of IL-1 alpha mRNA in both primary TFC and HTori3 cultures. IL-6 and IL-8 mRNA levels were increased by the addition of IL-1 in both cell types, and this effect was detected throughout the 24-h time-course. IFN-gamma (100 U/ml) had no significant effect on cytokine gene expression. A higher concentration of IFN-gamma (500 U/ml) had no significant effect on the expression of IL-1 alpha or IL-8 but produced an increase in the level of IL-6 mRNA in primary cultures and in HTori3 cells. Addition of TSH (1 mU/ml) produced an increase in the level of IL-1 alpha mRNA in primary TFC and HTori3 cells, at 12 and 24 h. TSH had no significant effect on the expression of IL-6 or IL-8 mRNA. These results demonstrate that human TFCs constitutively express IL-1 alpha, IL-6 and IL-8 mRNA and that this expression can be modulated by IL-1, IFN-gamma and TSH.
J Mol Endocrinol 1995 Aug
PMID:Semi-quantitative analysis of interleukin-1 alpha, interleukin-6 and interleukin-8 mRNA expression by human thyrocytes. 854 10

Incubation of human A549/8 cells with human interleukin-1 beta (50 units/ml), interferon-gamma (100 units/ml), and tumor necrosis factor-alpha (10 ng/ml) (cytomix) resulted in a marked expression of the mRNA of the inducible nitric oxide synthase (NOS II). This induction was prevented by cycloheximide. Dexamethasone markedly reduced cytokine-induced NOS II mRNA concentrations; this reduction was prevented by RU 38486 (mifepristone). Pyrrolidine dithiocarbamate, an inhibitor of nuclear factor-kappa B (NF-kappa B) activation, also significantly decreased cytomix-induced NOS II mRNA levels. When A549/8 cells were transfected with a construct containing 1570-bp 5'-flanking sequence of the murine NOS II gene cloned before a reporter gene, the murine NOS II promoter was induced up to 20-fold with cytomix but not with bacterial lipopolysaccharide. Dexamethasone as well as pyrrolidine dithiocarbamate inhibited this induction. In electrophoretic mobility shift assays, nuclear protein extracts from cytomix-induced, but not from unstimulated cells, significantly slowed the migration of an oligonucleotide containing the NF-kappa B-binding site. This band shift was markedly reduced by dexamethasone. On the other hand, cytomix-induced nuclear protein content of NF-kappa B p65 and NF-kappa B p50 was not reduced by dexamethasone (as analyzed by Western blot). Dexamethasone also did not reduce cytomix-induced expression of NF-kappa B p65 mRNA or enhance the expression of NF-kappa B inhibitor mRNA. The human and murine NOS II promoters also contain consensus sequences for activating protein-1 (AP-1) binding. However, AP-1 binding activity of nuclear extracts of A549/8 cells was not enhanced by cytomix or inhibited by dexamethasone. These data suggest that the activated glucocorticoid receptor prevents (by a protein/protein interaction) the binding of transcription factor NF-kappa B, but not AP-1, to the NOS II promoter, thereby inhibiting the induction of NOS II transcription.
Mol Pharmacol 1996 Jan
PMID:Glucocorticoids inhibit the induction of nitric oxide synthase II by down-regulating cytokine-induced activity of transcription factor nuclear factor-kappa B. 856 1

1. Recent data have shown that interleukin-10 (IL-10) is expressed and acts in mouse pituitary tumor cells and freshly isolated mouse pituitaries. 2. In this study, we show that poly(A+) RNA derived from normal human pituitary and hypothalamus expresses IL-10 message. 3. The majority of transcripts was likely from the pituitary and hypothalamus, and not from lymphocytes in the pituitary and hypothalamic vasculature, since both IL-10 and interferon-gamma mRNA levels, compared to equivalent amounts of RNA from peripheral blood lymphocytes, were much lower. 4. These results indicate that IL-10 may function in human neuroendocrine process as it does in the murine system, thus serving as an important signal molecule for bidirectional communication between the neuroendocrine and the immune systems.
Cell Mol Neurobiol 1995 Apr
PMID:Presence of interleukin-10 transcripts in human pituitary and hypothalamus. 859 Apr 58


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