Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P05412 (c-Jun)
11,453 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effect of piceatannol on lipopolysaccharide (LPS)-induced nitric oxide (NO) production was examined. Piceatannol significantly inhibited NO production in LPS-stimulated RAW 264.7 cells. The inhibition was due to the reduced expression of an inducible isoform of NO synthase (iNOS). The inhibitory effect of piceatannol was mediated by down-regulation of LPS-induced nuclear factor (NF)-kappaB activation, but not by its cytotoxic action. Piceatannol inhibited IkappaB kinase (IKK)-alpha and beta phosphorylation, and subsequently IkappaB-alpha phosphorylation in LPS-stimulated RAW 264.7 cells. On the other hand, piceatannol did not affect activation of mitogen-activated protein (MAP) kinases including extracellular signal regulated kinase 1/2 (Erk1/2), p38 and stress-activated protein kinase/c-Jun NH2-terminal kinase (SAPK/JNK). Piceatannol inhibited the phosphorylation of Akt and Raf-1 molecules, which regulated the activation of IKK-alpha and beta phosphorylation. The detailed mechanism of the inhibition of LPS-induced NO production by piceatannol is discussed.
...
PMID:Piceatannol prevents lipopolysaccharide (LPS)-induced nitric oxide (NO) production and nuclear factor (NF)-kappaB activation by inhibiting IkappaB kinase (IKK). 1550 5

Hyperbaric oxygen (HBO) is increasingly used in a number of areas of medical practice, such as selected problem infections and wounds. The beneficial effects of HBO in treating ischemia-related wounds may be mediated by stimulating angiogenesis. We sought to investigate VEGF, the main angiogenic regulator, regulated by HBO in human umbilical vein endothelial cells (HUVECs). In this study, we found that VEGF was up regulated both at mRNA and protein levels in HUVECs treated with HBO dose- and time-dependently. Since there are several AP-1 sites in the VEGF promoter, and the c-Jun/AP-1 is activated through stress-activated protein kinase/c-Jun N-terminal kinase (SAPK/JNK) and extracellular signal regulated kinase (ERK), we further examined the c-Jun, JNK and ERK that might be involved in the VEGF induced by HBO. The VEGF mRNA induced by HBO was blocked by both PD98059 and SP600125, the ERK and JNK inhibitors respectively. HBO induced phospho-ERK and phospho-JNK expressions within 15 min. We further demonstrated that c-Jun phosphorylation was induced within 60 min of HBO treatment. HBO also induced the nuclear AP-1 binding ability within 30-60 min, but the AP-1 induction was blocked by treatment with either the ERK or JNK inhibitor. To verify that the VEGF expression induced by HBO is through the AP-1 trans-activation and VEGF promoter, both the VEGF promoter and AP-1 driving luciferase activity were found increased by the cells treated with HBO. The c-Jun mRNA, which is also driven by AP-1, was also induced by HBO, and the induction of c-Jun was blocked by ERK and JNK inhibitors. We suggest that VEGF induced by HBO is through c-Jun/AP-1 activation, and through simultaneous activation of ERK and JNK pathways.
...
PMID:Hyperbaric oxygen induces VEGF expression through ERK, JNK and c-Jun/AP-1 activation in human umbilical vein endothelial cells. 1632 81

CNS inflammation mediated by microglial activation can result in neuronal and glial cell death in a variety of neurodegenerative and demyelinating diseases. Minocycline, a second-generation tetracycline, has profound anti-inflammatory properties in the CNS mediated, in part, by inhibition of microglia. MAPK and nuclear factor-kappaB (NF-kappaB) activation are hallmarks of activated microglia and they are critical for the expression of many inflammatory mediators. In the present study, we investigated minocycline effects on activation of p38, c-Jun-N-terminal activated protein kinase (JNK) 1/2 and extracellular signal regulated kinase (ERK) 1/2 MAPKs and inhibitor alpha of NF-kappaB (IkappaBalpha) degradation in BV-2 and primary microglial cells. Our results demonstrate that minocycline has the ability to inhibit all MAPKs but these effects strongly depend on the stimulus used for MAPK activation. Minocycline significantly decreased activation of all lipopolysaccharide-stimulated MAPKs but it was without effect on MAPKs activated by H2O2. Minocycline inhibited JNK1/2 and ERK1/2 but not p38 when stimulated by 2',3'-O-(4-benzoylbenzoyl)-adenosine 5'-triphosphate, indicating that minocycline affects only certain upstream signaling target(s) that are stimulus-specific. Our data also suggest that protein kinase C (PKC) inhibition may be partially involved in the minocycline mechanism of MAPK inhibition. In addition, minocycline attenuated lipopolysaccharide-stimulated degradation of IkappaBalpha implying a possible inhibitory role on NF-kappaB transcriptional activity.
...
PMID:Minocycline exerts inhibitory effects on multiple mitogen-activated protein kinases and IkappaBalpha degradation in a stimulus-specific manner in microglia. 1633 36

Insulin-like growth factor binding protein-2 (IGFBP-2), the second most abundant IGFBP in the circulation, is dramatically increased in the serum and ovarian cyst fluid of women with epithelial ovarian cancer. The specific role of IGFBP-2 in ovarian carcinogenesis remains elusive. Using NIH-OVCAR3 human epithelial ovarian cancer cells, we have evaluated the effects of IGFBP-2 and its antibody on cell proliferation, activation of mitogen-activated protein kinase (MAP kinase) pathways and on cytokine expression. Treatment of the cells with IGFBP-2 stimulates cell growth significantly (p<.05) and potentiates the activation of (1) the extracellular signal regulated kinase (ERK1/2) signaling pathway, which transduces cell-specific growth and differentiation signals; (2) the stress-activated protein kinases/c-Jun N-terminal kinases (SAPK/JNK) pathway, which is activated by environmental stresses, inflammatory cytokines, growth factors and G-protein coupled receptor (GPCR) agonists; and (3) the p38 MAP kinase pathway, which mediates inflammatory and stress responses. Suppression of IGFBP-2, with its neutralizing antibody, significantly (p<.05) retards cell growth, blocks the activation of all three cascades of the MAPK pathways and downregulates the expression of a number of potential cancer-promoting cytokines. These novel findings may have important clinical implications for developing innovative strategies for the treatment and management of ovarian cancer.
...
PMID:Insulin-like growth factor binding protein-2 stimulates proliferation and activates multiple cascades of the mitogen-activated protein kinase pathways in NIH-OVCAR3 human epithelial ovarian cancer cells. 1635 19

Mammary tumor cells are required to degrade the surrounding matrix and disseminate in order to metastasize, and both of these processes are controlled by a tumor cell-signaling network that remains poorly defined. MEKK1 is a MAPKKK that regulates both the extracellular signal regulated kinase (ERK1/2) and the c-Jun amino terminal kinase (JNK) signaling pathways. MEKK1 signaling regulates migration through control of cell adhesion and is required for inducible expression of urokinase-type plasminogen activator (uPA). MEKK1-deficient mice with mammary gland-targeted expression of the polyoma middle T antigen (PyMT) transgene develop primary mammary tumors at a rate and frequency similar to wild-type littermates, indicating that MEKK1 deficiency does not affect PyMT-mediated transformation. However, MEKK1-/- mice display significantly delayed tumor cell dissemination and lung metastasis. Delayed MEKK1-dependent tumor dissemination is associated with markedly reduced tumor uPA expression, gelatinase activity, and prolonged tumor basement membrane integrity. siRNA-mediated MEKK1 knockdown inhibits uPA activity, cell migration and invasion in MDA-MB-231 human breast cancer cells. Thus MEKK1 controls tumor progression by regulating both the migration and proteolysis aspects of tumor cell invasiveness. To our knowledge, this is the first example of a MAPKKK that regulates metastasis through control of tumor invasiveness.
...
PMID:MEKK1 controls matrix degradation and tumor cell dissemination during metastasis of polyoma middle-T driven mammary cancer. 1656 86

Although gonadal hormone mostly causes genotropic actions through the members of nuclear receptor family, it also can regulate these actions via membrane receptor. To explore the possibility of plasma membrane estrogen receptors (mER) mediating genotropic events, we have investigated estrogen's effect on nicotine-stimulated adhesion molecule expression and evaluated whether this effect depends on calcium, MAPK signal pathway. Fluorescence Spectroscopy analysis of Ca2+ from human umbilical vein endothelial cells (HUVECs) showed through mER, estrogen induced a rapid rise of intracellular free Ca2+ concentration and this rise could not be inhibited by tamoxifen (classic ER inhibitor). In the context of nicotine stimulating, however, estrogen attenuated phosphorylation of mitogen-activated protein kinase (MAPK) family members, extracellular signal regulated kinase 1/2 (ERK1/2), p38 but not c-Jun-N-terminal kinase (JNK) in HUVECs and this effect could not still be prevented by tamoxifen. In the meantime, estrogen also down-regulated surface/soluble vascular cell adhesion molecule (VCAM-1, sVCAM-1) and endothelial selectin (E-selectin, sE-selectin) levels, which was not abolished by tamoxifen either. Moreover, calcium chelator BAPTA, ERK1/2 inhibitor PD98059, p38 inhibitor SB203580 significantly reduced the production of nicotine-activated surface/soluble VCAM-1 and E-selectin and both of the remained levels were no longer regulated by estrogen. Our study here provides the information of decrease effect of mER-mediated estrogen through Ca2+ and ERK1/2, p38 MAPK signaling pathway on nicotine-stimulated expression of surface/soluble VCAM-1 and E-selectin in HUVECs.
...
PMID:Estrogen down-regulates nicotine-induced adhesion molecule expression via nongenomic signal pathway in endothelial cells. 1664 74

The regulated dephosphorylation of mitogen-activated protein kinases (MAPKs) plays a key role in determining the magnitude and duration of kinase activation and hence the physiological outcome of signalling. In mammalian cells, an important component of this control is mediated by the differential expression and activities of a family of 10 dual-specificity (Thr/Tyr) MAPK phosphatases (MKPs). These enzymes share a common structure in which MAPK substrate recognition is determined by sequences within an amino-terminal non-catalytic domain whereas MAPK binding often leads to a conformational change within the C-terminal catalytic domain resulting in increased enzyme activity. MKPs can either recognize and inactivate a single class of MAP kinase, as in the specific inactivation of extracellular signal regulated kinase (ERK) by the cytoplasmic phosphatase DUSP6/MKP-3 or can regulate more than one MAPK pathway as illustrated by the ability of DUSP1/MKP-1 to dephosphorylate ERK, c-Jun amino-terminal kinase and p38 in the cell nucleus. These properties, coupled with transcriptional regulation of MKP expression in response to stimuli that activate MAPK signalling, suggest a complex negative regulatory network in which individual MAPK activities can be subject to negative feedback control, but also raise the possibility that signalling through multiple MAPK pathways may be integrated at the level of regulation by MKPs.
...
PMID:Differential regulation of MAP kinase signalling by dual-specificity protein phosphatases. 1749 16

The HER2/neu oncogene is an important diagnostic and prognostic factor and therapeutic target in breast and other cancers. We developed and characterized a breast cancer cell line (Bam1a) that overexpresses the activated HER2/neu and ErbB-3 and has a gene expression profile consistent with the ErbB-2 genetic signature. We evaluated the effects of the epidermal growth factor receptor (EGFR)/HER2 inhibitor, gefitinib, on this breast tumor line in vitro and in vivo. We characterized the effects of gefitinib on EGFR, HER2, and ErbB-3 phosphorylation by Western blot and determined the effects on downstream signaling through growth, survival, and stress pathways and the effect on proliferation, cell cycle, and apoptosis. Gefitinib treatment diminished phosphorylation of the ErbB-3 > EGFR > HER2/neu and signal transducers and activators of transcriptions in a dose-dependent fashion. Downstream mitogenic signaling through mitogen-activated protein (MAP)/extracellular signal regulated kinase kinase, p44/42 MAP kinase (MAPK) and stress signaling through c-Jun-NH(2)-kinase (JNK) 1 and c-Jun was impaired (1 micromol/L, 4-24 h), leading to cytostasis and cell cycle arrest within 24 h by decreased cyclin D1, cyclin B1, and p(Ser795)Rb and increased p27. Proliferation and colony formation were inhibited at 0.5 and 1 micromol/L, respectively, and correlated with altered gene expression profiles. Diminished survival signaling through Akt, induction of bim, loss of connexin43, and decreased production of vascular endothelial growth factor-D preceded caspase-3 and poly(ADP)ribose polymerase (PARP) cleavage and apoptosis (>50% 2 micromol/L, 48 h). Oral administration of gefitinib was able to prevent the outgrowth of Bam1a tumor cells from palpable lesions, shrink established tumors, eliminate HER2 and HER3 phosphorylation, and decrease MAPK and Akt signaling in vivo. A variant of the Bam1a cell line, IR-5, with acquired ability to grow in 5 micromol/L gefitinib was developed and characterized. IR-5 bears a novel point mutation in the HER2/neu that corresponds to a L726I in the ATP-binding pocket and correlates with a log decrease in sensitivity to gefitinib, increased heterodimerization with EGFR and HER3, and impaired down-regulation. Gene expression profiling of IR-5 showed increased expression of EMP-1, NOTCH-1, FLT-1, PDGFB, and several other genes that may contribute to the resistant phenotype and sustain signaling through MAPK and Akt. This model will be useful in understanding the differences between intrinsic drug sensitivity and acquired resistance in the context of therapeutic strategies that target oncogene addicted diseases.
...
PMID:Breast cancer expressing the activated HER2/neu is sensitive to gefitinib in vitro and in vivo and acquires resistance through a novel point mutation in the HER2/neu. 1763 94

Anti-ribosomal phosphoprotein autoantibodies have been shown to be significantly associated with multiple manifestations of systemic lupus erythematosus (SLE). High levels of interleukin-10 (IL-10) have been demonstrated to contribute to lupus susceptibility and severity. In this study, we investigated the molecular mechanisms of anti-ribosomal phosphoprotein monoclonal antibody (anti-P mAb)-induced autoimmune responses. Anti-P mAb promoted IL-10 overproduction in a dose- and time-dependent manner in both lipopolysaccharide (LPS)-activated RAW 264.7 cells and primary human macrophages. Anti-P mAb enhanced phosphorylation of Akt (PKB; protein kinase B), extracellular signal regulated kinase 1/2 (ERK1/2) and c-Jun NH2-terminal kinase 1/2 (JNK1/2), while phosphorylation of p38 remained unaltered. Furthermore, anti-P mAb decreased glycogen synthase kinase 3 (GSK3) activity and reduced the phosphorylation of I kappaB alpha in LPS-activated macrophages. The Syk, phosphatidylinositol 3-kinase (PI3K), protein kinase C (PKC), JNK and ERK signalling pathways involved in anti-P mAb-triggered IL-10 secretion were also confirmed using various pharmacological inhibitors. In addition, nuclear factor (NF)-kappaB had negative regulatory effects on anti-P mAb-triggered IL-10 secretion. Using reporter plasmids containing the nuclear factor binding sites of NF-kappaB, cAMP-enhanced activation protein 1 (AP-1), serum response element (SRE) or cyclic AMP response element (CRE), treatment of anti-P mAb led to activation of the corresponding factors that bind to the AP-1 site, SRE and CRE in the LPS-activated macrophages. Furthermore, by transfection with reporter plasmids bearing various lengths of the IL-10 promoter, the AP-1 binding site, SRE and CRE were shown to be required for anti-P mAb-induced effects. Collectively, our results provide a molecular model for anti-P mAb-induced IL-10 overproduction in LPS-activated macrophages, which may play a role in the pathogenesis of SLE.
...
PMID:Anti-ribosomal phosphoprotein autoantibody triggers interleukin-10 overproduction via phosphatidylinositol 3-kinase-dependent signalling pathways in lipopolysaccharide-activated macrophages. 1877 81

Overexpression of epidermal growth factor (EGF) and urokinase plasminogen activator receptor (uPAR) have been observed in human gastric cancers. However, the interaction between EGF and uPAR in gastric cancer has not been well elucidated. In this study, we investigated the effect of EGF on uPAR expression and the underlying signal pathways in human gastric cancer AGS cells. EGF induced uPAR mRNA expression in a time- and concentration-dependent manner. EGF also induced uPAR promoter activity. In addition, EGF induced the activation of extracellular signal regulated kinase-1/2 (ERK-1/2) and P38 mitogen-activated protein kinase (MAPK) but not the activation of c-Jun amino terminal kinase. A specific inhibitor of MEK-1 (an upstream effector of ERK-1/2) and a dominant negative MEK-1 were able to suppress the EGF-induced uPAR promoter activity. Site-directed mutagenesis and electrophoretic mobility shift assays demonstrated that the binding sites of transcription factors, activator protein-1 (AP-1) and nuclear factor (NF)-kappaB, are involved in the EGF-induced uPAR transcription. Suppression of the EGF-induced uPAR promoter activity by the AP-1 decoy oligonuclotide, as well as expression vectors encoding mutated-type NF-kappaB-inducting kinase and I-kappaB, confirmed that the activation of AP-1 and NF-kappaB are essential for the EGF-induced uPAR upregulation. The AGS cells pretreated with EGF showed a remarkably enhanced invasiveness and this effect was partially abrogated by uPAR neutralizing antibodies and by the inhibitors of ERK-1/2, AP-1, and NF-kappaB. The above results suggest that EGF induces uPAR expression via ERK-1/2, AP-1, and NF-kappaB signaling pathways and, in turn, stimulates cell invasiveness in human gastric cancer AGS cells.
...
PMID:EGF stimulates uPAR expression and cell invasiveness through ERK, AP-1, and NF-kappaB signaling in human gastric carcinoma cells. 1902 Jul 43


<< Previous 1 2 3 4 5 6 Next >>