Search results for "MAP kinase"
showing 10 items of 178 documents
Activation of mitogen-activated protein kinase by the bradykinin B2receptor is independent of receptor phosphorylation and phosphorylation-triggered …
1999
Recent evidence suggests that serine/threonine phosphorylation and internalization of beta2-adrenergic receptors play critical roles in signalling to the mitogen-activated protein kinase cascade. To investigate whether this represents a general mechanism employed by G protein-coupled receptors, we studied the requirement of these processes in the activation of mitogen-activated protein kinase by G alpha(q)-coupled bradykinin B2 receptors. Mutant B2 receptors impaired in receptor phosphorylation and internalization are fully capable to activate mitogen-activated protein kinase. Bradykinin-induced long-term effects on mitogenic signalling monitored by measuring the transcriptional activity of…
Endothelial cells and normal breast epithelial cells enhance invasion of breast carcinoma cells by CXCR-4-dependent up-regulation of urokinase-type p…
2008
Here we show the increase of invasion of three breast cancer cell lines (8701-BC, MDA-MB-231 and SKBR3) upon long-term co-incubation with culture medium of normal microvascular endothelial cells (MVEC) and normal breast epithelial cells (HB2). The enhancement of invasion relied on the interaction of microvascular endothelial cell and normal breast epithelial cell CXCL12 (SDF1) chemokine, whose expression by breast cancer cells was very low, with the cognate CXCR4 receptor of malignant cells, which resulted in over-expression of the urokinase-type plasminogen activator receptor (uPAR) on their surfaces. uPAR over-expression, showed by RT-PCR and Western blotting, was paralleled by increased …
Decreased SAPK/JNK signalling affects cytokine release and STAT3 activation in psoriatic fibroblasts.
2015
Tristetraprolin regulation of interleukin-22 production
2015
AbstractInterleukin (IL)-22 is a STAT3-activating cytokine displaying characteristic AU-rich elements (ARE) in the 3′-untranslated region (3′-UTR) of its mRNA. This architecture suggests gene regulation by modulation of mRNA stability. Since related cytokines undergo post-transcriptional regulation by ARE-binding tristetraprolin (TTP), the role of this destabilizing protein in IL-22 production was investigated. Herein, we demonstrate that TTP-deficient mice display augmented serum IL-22. Likewise, IL-22 mRNA was enhanced in TTP-deficient splenocytes and isolated primary T cells. A pivotal role for TTP is underscored by an extended IL-22 mRNA half-life detectable in TTP-deficient T cells. Lu…
Convergence of the target of rapamycin and the Snf1 protein kinase pathways in the regulation of the subcellular localization of Msn2, a transcriptio…
2002
The subcellular localization of Msn2, a transcriptional activator of STRE (stress response element)-regulated genes, is modulated by carbon source availability. In cells growing in glucose, Msn2 is located mainly in the cytosol, whereas in carbon source-starved cells, Msn2 is located largely inside the nucleus. However, in cells lacking Reg1 (the regulatory subunit of the Reg1/Glc7 protein phosphatase complex), the regulation of subcellular distribution is absent, Msn2 being constitutively present in the cytosol. The localization defect in these mutants is specific for carbon starvation stress, and it is because of the presence of an abnormally active Snf1 protein kinase that inhibits the n…
The development of benzimidazoles as selective rho kinase inhibitors
2010
Rho Kinase (ROCK) is a serine/threonine kinase whose inhibition could prove beneficial in numerous therapeutic areas. We have developed a promising class of ATP-competitive inhibitors based upon a benzimidazole scaffold, which show excellent potency toward ROCK (IC(50)<10nM). This report details the optimization of selectivity for ROCK over other related kinases such as Protein kinase A (PKA).
The mitotic kinase Aurora-A promotes distant metastases by inducing epithelial-to-mesenchymal transition in ERα+ breast cancer cells
2013
In this study, we demonstrate that constitutive activation of Raf-1 oncogenic signaling induces stabilization and accumulation of Aurora-A mitotic kinase that ultimately drives the transition from an epithelial to a highly invasive mesenchymal phenotype in estrogen receptor α-positive (ERα(+)) breast cancer cells. The transition from an epithelial- to a mesenchymal-like phenotype was characterized by reduced expression of ERα, HER-2/Neu overexpression and loss of CD24 surface receptor (CD24(-/low)). Importantly, expression of key epithelial-to-mesenchymal transition (EMT) markers and upregulation of the stemness gene SOX2 was linked to acquisition of stem cell-like properties such as the ab…
A systems biology perspective on cholangiocellular carcinoma development: focus on MAPK-signaling and the extracellular environment.
2008
Background/Aims Multiple genes have been implicated in cholangiocellular carcinoma (CCC) development. However, the overall neoplastic risk is likely associated with a much lower number of critical physiological pathways. Methods To investigate this hypothesis, we extracted all published genetic associations for the development of CCC from PubMed (genetic association studies, but also studies associating genes and CCC in general, i.e. functional studies in cell lines, genetic studies in humans, knockout mice etc.) and integrated CCC microarray data. Results We demonstrated the MAPK pathway was consistently enriched in CCC. Comparing our data to genetic associations in HCC often successfully …
Hematopoietic stem cell quiescence and function are controlled by the CYLD–TRAF2–p38MAPK pathway
2015
Tesio at al. identify a novel pathway controlled by the tumor suppressor and deubiquitinase cylindromatosis (CYLD), which is involved in the regulation of hematopoietic stem cell quiescence and repopulation potential.
JNK phosphorylation relieves HDAC3-dependent suppression of the transcriptional activity of c-Jun
2003
The AP-1 transcription factor c-Jun is a prototypical nuclear effector of the JNK signal transduction pathway. The integrity of JNK phosphorylation sites at serines 63/73 and at threonines 91/93 in c-Jun is essential for signal-dependent target gene activation. We show that c-Jun phosphorylation mediates dissociation of an inhibitory complex, which is associated with histone deacetylase 3 (HDAC3). The subsequent events that ultimately cause increased mRNA synthesis are independent of c-Jun phosphorylation and its interaction with JNK. These findings provide an 'activation by de-repression' model as an explanation for the stimulatory function of JNK on c-Jun.