Search results for "MAPK"
showing 10 items of 238 documents
Acquired BRAF inhibitor resistance: A multicenter meta-analysis of the spectrum and frequencies, clinical behaviour, and phenotypic associations of r…
2015
BackgroundAcquired resistance to BRAF inhibitors (BRAFi) is a near-universal phenomenon caused by numerous genetic and non-genetic alterations. In this study, we evaluated the spectrum, onset, pattern of progression, and subsequent clinical outcomes associated with specific mechanisms of resistance.MethodsWe compiled clinical and genetic data from 100 patients with 132 tissue samples obtained at progression on BRAFi therapy from 3 large, previously published studies of BRAFi resistance. These samples were subjected to whole-exome sequencing and/or polymerase chain reaction-based genetic testing.ResultsAmong 132 samples, putative resistance mechanisms were identified in 58%, including NRAS o…
Phospho-p38 MAPK expression in COPD patients and asthmatics and in challenged bronchial epithelium
2015
<b><i>Background:</i></b> The role of mitogen-activated protein kinases (MAPK) in regulating the inflammatory response in the airways of patients with chronic obstructive pulmonary disease (COPD) and asthmatic patients is unclear. <b><i>Objectives:</i></b> To investigate the expression of activated MAPK in lungs of COPD patients and in bronchial biopsies of asthmatic patients and to study MAPK expression in bronchial epithelial cells in response to oxidative and inflammatory stimuli. <b><i>Methods:</i></b> Immunohistochemical expression of phospho (p)-p38 MAPK, p-JNK1 and p-ERK1/2 was measured in bronchial mucosa in pat…
Traditional Chinese herbal medicine at the forefront battle against COVID-19: Clinical experience and scientific basis.
2020
Abstract Background Throughout the 5000-year history of China, more than 300 epidemics were recorded. Traditional Chinese herbal medicine (TCM) has been used effectively to combat each of these epidemics’ infections, and saved many lives. To date, there are hundreds of herbal TCM formulae developed for the purpose of prevention and treatment during epidemic infections. When COVID-19 ravaged the Wuhan district in China in early January 2020, without a deep understanding about the nature of COVID-19, patients admitted to the TCM Hospital in Wuhan were immediately treated with TCM and reported later with >90% efficacy. Approach We conducted conduct a systematic survey of various TCM herbal pre…
Shikonin reduces oedema induced by phorbol ester by interfering with IκBα degradation thus inhibiting translocation of NF-κB to the nucleus
2010
Background and purpose In the present paper we studied the effect of shikonin on ear oedema induced by 12-O-tetradecanoylphorbol-13-acetate (TPA), and determined the mechanisms through which shikonin might exert its topical anti-inflammatory action. Experimental approach Acute ear oedema was induced in mice by topical application of TPA. The in vitro assays used macrophages RAW 264.7 cells stimulated with lipopolysaccharide. Cyclooxygenase-2, inducible nitric oxide synthase, protein kinase Calpha, extracellular signal-regulated protein kinase (ERK), phosphorylated ERK (pERK), c-Jun N-terminal kinase (JNK), pJNK, p38, p-p38, p65, p-p65, inhibitor protein of nuclear factor-kappaB (NF-kappaB) …
Cucurbitacins as inducers of cell death and a rich source of potential anticancer compounds.
2011
Triterpenes have been reported to induce cell death. One relevant group of this family of compounds is cucurbitacins, which have been studied as inducers of apoptosis in various cancer cell lines. The most significant mechanisms with regard to the apoptotic effects of cucurbitacins are their ability to modify transcriptional activities via nuclear factors or genes and their capability to activate or inhibit pro- or anti-apoptotic proteins. Still, while the majority of studies on these compounds have dealt with their apoptotic effects on cancer cell lines, several research groups have also explored their anti-inflammatory activities. In general, cucurbitacins are considered to be selective i…
The immunosuppressive activity of artemisinin‐type drugs towards inflammatory and autoimmune diseases
2021
The sesquiterpene lactone artemisinin from Artemisia annua L. is well established for malaria therapy, but its bioactivity spectrum is much broader. In this review, we give a comprehensive and timely overview of the literature regarding the immunosuppressive activity of artemisinin-type compounds toward inflammatory and autoimmune diseases. Numerous receptor-coupled signaling pathways are inhibited by artemisinins, including the receptors for interleukin-1 (IL-1), tumor necrosis factor-α (TNF-α), β3-integrin, or RANKL, toll-like receptors and growth factor receptors. Among the receptor-coupled signal transducers are extracellular signal-regulated protein kinase (ERK), c-Jun N-terminal kinas…
Symmetry Breaking and Establishment of Dorsal/Ventral Polarity in the Early Sea Urchin Embryo
2015
The mechanisms imposing the Dorsal/Ventral (DV) polarity of the early sea urchin embryo consist of a combination of inherited maternal information and inductive interactions among blastomeres. Old and recent studies suggest that a key molecular landmark of DV polarization is the expression of nodal on the future ventral side, in apparent contrast with other metazoan embryos, where nodal is expressed dorsally. A subtle maternally-inherited redox anisotropy, plus some maternal factors such as SoxB1, Univin, and p38-MAPK have been identified as inputs driving the spatially asymmetric transcription of nodal. However, all the mentioned factors are broadly distributed in the embryo as early as no…
Calcitonin gene-related peptide partly protects cultured smooth muscle cells from apoptosis induced by an oxidative stress via activation of ERK1/2 M…
2003
Abstract Oxidative stress induced by a glucose/glucose oxidase (G/GO) generator system dose-dependently decreased the viability of cultured vascular smooth muscle cells (VSMC) as estimated by MTT assay. Cell death was induced in 40% of cells exposed to 0.2 IU/ml of the free radical generating mixture. Annexin-V labeling, Hoechst staining together with DNA laddering demonstrated that apoptosis was responsible for this cell loss. Pretreatment of the cells with 10−8 M calcitonin gene-related peptide (CGRP) significantly attenuated the damaging effect of the oxidative stress. Indeed, cell viability was estimated to be 80% in CGRP-treated group, instead of 60% in absence of CGRP treatment. This …
ErbB-3 activation by NRG-1β sustains growth and promotes vemurafenib resistance in BRAF-V600E colon cancer stem cells (CSCs)
2015
Approximately 5-10% of metastatic colorectal cancers harbor a BRAF-V600E mutation, which is correlated with resistance to EGFR-targeted therapies and worse clinical outcome. Vice versa, targeted inhibition of BRAF-V600E with the selective inhibitor PLX 4032 (Vemurafenib) is severely limited due to feedback re-activation of EGFR in these tumors. Mounting evidence indicates that upregulation of the ErbB-3 signaling axis may occur in response to several targeted therapeutics, including Vemurafenib, and NRG-1β-dependent re-activation of the PI3K/AKT survival pathway has been associated with therapy resistance. Here we show that colon CSCs express, next to EGFR and ErbB-2, also significant amoun…
B-Raf Acts via the ROCKII/LIMK/Cofilin Pathway To Maintain Actin Stress Fibers in Fibroblasts
2004
Members of the Raf family of serine/threonine protein kinases have been well studied in a variety of organisms ranging from Drosophila to humans. Three raf homologues (raf-1, B-raf, and A-raf) exist in mammals, while a single prototypic homologue exists in lower organisms. A wealth of genetic and biochemical data have indicated that Raf family members are signaling kinases that are integral components of the conserved Ras/Raf/MEK/ERK signaling cascade. Following activation by Ras-dependent mechanisms, Raf protein kinases act as mitogen-activated protein (MAP) kinase kinase kinases, which phosphorylate and activate the type 1/2 MAP kinase kinases, also known as MEK1/2. These dual-specificity…