Showing papers on "Receptor tyrosine kinase published in 2002"
TL;DR: Members of the nerve growth factor and glial cell line-derived neurotrophic factor families — comprising neurotrophins and GDNF-family ligands (GFLs) — are crucial for the development and maintenance of distinct sets of central and peripheral neurons.
Abstract: Members of the nerve growth factor (NGF) and glial cell line-derived neurotrophic factor (GDNF) families — comprising neurotrophins and GDNF-family ligands (GFLs), respectively — are crucial for the development and maintenance of distinct sets of central and peripheral neurons. Knockout studies in the mouse have revealed that members of these two families might collaborate or act sequentially in a given neuron. Although neurotrophins and GFLs activate common intracellular signalling pathways through their receptor tyrosine kinases, several clear differences exist between these families of trophic factors.
1,711 citations
TL;DR: It is shown that VEGF expression correlates with Stat3 activity in diverse human cancer cell lines and indicates that Stat3 represents a common molecular target for blocking angiogenesis induced by multiple signaling pathways in human cancers.
Abstract: Non-receptor and receptor tyrosine kinases, such as Src and EGF receptor (EGFR), are major inducers of vascular endothelial growth factor (VEGF), one of the most potent mediators of angiogenesis. While tyrosine kinases signal through multiple pathways, signal transducer and activation of transcription 3 (Stat3) is a point of convergence for many of these and is constitutively activated with high frequency in a wide range of cancer cells. Here, we show that VEGF expression correlates with Stat3 activity in diverse human cancer cell lines. An activated Stat3 mutant (Stat3C) up-regulates VEGF expression and stimulates tumor angiogenesis. Stat3C-induced VEGF up-regulation is abrogated when a Stat3-binding site in the VEGF promoter is mutated. Furthermore, interrupting Stat3 signaling with dominant-negative Stat3 protein or Stat3 antisense oligonucleotide in tumor cells down-regulates VEGF expression. Consistent with an important role of Stat3 in VEGF up-regulation induced by various oncogenic tyrosine kinases, v-Src-mediated VEGF expression is inhibited when Stat3 signaling is blocked. Moreover, chromatin immunoprecipitation assays indicate that Stat3 protein binds to the VEGF promoter in vivo and mutation of a Stat3-binding site in the VEGF promoter abrogates v-Src-induced VEGF promoter activity. These studies provide evidence that the VEGF gene is regulated directly by Stat3 protein, and indicate that Stat3 represents a common molecular target for blocking angiogenesis induced by multiple signaling pathways in human cancers.
1,171 citations
TL;DR: The crystal structure of a 2:2 complex of human EGF and the EGFR extracellular region has been determined at 3.3 A resolution and the unique "receptor-mediated dimerization" was verified by EGFR mutagenesis.
1,165 citations
TL;DR: It is found that the EGFRK activation loop adopts a conformation similar to that of the phosphorylated active form of the kinase domain from the insulin receptor, which is distinguished from all other known receptor tyrosine kinases in possessing constitutive kinase activity without a phosphorylation event within their kinase domains.
1,162 citations
TL;DR: The concept of bidirectional signalling has emerged as an important mechanism by which Ephs and ephrins control the output signal in processes of cell–cell communication.
Abstract: Eph receptors constitute the largest family of tyrosine kinase receptors and, together with their plasma-membrane-bound ephrin ligands, have many important functions during development and adulthood. In contrast with most receptor tyrosine kinases, unidirectional signalling can originate from the ephrin ligands as well as from the Eph receptors. Furthermore, the concept of bidirectional signalling has emerged as an important mechanism by which Ephs and ephrins control the output signal in processes of cell–cell communication.
1,161 citations
TL;DR: In this article, the imidazo[1,2-a]pyrimidine derivatives are used for treating cellular proliferative diseases, for treating disorders associated with MET activity, and for inhibiting the receptor tyrosine kinase MET.
Abstract: The present invention relates to imidazo[1,2-a]pyrimidine derivatives, that are useful for treating cellular proliferative diseases, for treating disorders associated with MET activity, and for inhibiting the receptor tyrosine kinase MET. The invention also related to compositions which comprise these compounds, and methods of using them to treat cancer in mammals.
1,135 citations
TL;DR: In human cancer cells, both intratumoral hypoxia and genetic alterations affecting signal transduction pathways lead to increased HIF-1 activity, which promotes angiogenesis, metabolic adaptation, and other critical aspects of tumor progression.
859 citations
TL;DR: Recent studies of protein tyrosine kinases and G-protein-coupled receptors have shed new light on the mechanisms and functional consequences of this bidirectional interplay between signalling and membrane-transport networks.
Abstract: Binding of hormones, growth factors and other cell modulators to cell-surface receptors triggers a complex array of signal-transduction events. The activation of many receptors also accelerates their endocytosis. Endocytic transport is important in regulating signal transduction and in mediating the formation of specialized signalling complexes. Conversely, signal-transduction events modulate specific components of the endocytic machinery. Recent studies of protein tyrosine kinases and G-protein-coupled receptors have shed new light on the mechanisms and functional consequences of this bidirectional interplay between signalling and membrane-transport networks.
848 citations
TL;DR: Physiological analysis revealed the onset of multiple independent parameters of dilated cardiomyopathy, including chamber dilation, wall thinning and decreased contractility, and suggested ErbB2 signaling inCardiomyocytes is essential for the prevention of Dilated carduomyopathy.
Abstract: Amplification of the gene encoding the ErbB2 (Her2/neu) receptor tyrosine kinase is critical for the progression of several forms of breast cancer. In a large-scale clinical trial, treatment with Herceptin (trastuzumab), a humanized blocking antibody against ErbB2, led to marked improvement in survival. However, cardiomyopathy was uncovered as a mitigating side effect, thereby suggesting an important role for ErbB2 signaling as a modifier of human heart failure. To investigate the physiological role of ErbB2 signaling in the adult heart, we generated mice with a ventricular-restricted deletion of Erbb2. These ErbB2-deficient conditional mutant mice were viable and displayed no overt phenotype. However, physiological analysis revealed the onset of multiple independent parameters of dilated cardiomyopathy, including chamber dilation, wall thinning and decreased contractility. Additionally, cardiomyocytes isolated from these conditional mutants were more susceptible to anthracycline toxicity. ErbB2 signaling in cardiomyocytes is therefore essential for the prevention of dilated cardiomyopathy.
812 citations
TL;DR: Regulatory mechanisms provide not only redundancy but also diversity in the control of catecholamine biosynthesis.
Abstract: Tyrosine hydroxylase catalyzes the rate-limiting step in the biosynthesis of the catecholamines dopamine, norepinephrine, and epinephrine. Therefore, the regulation of tyrosine hydroxylase enzyme number and intrinsic enzyme activity represents the central means for controlling the synthesis of these important biogenic amines. An intricate scheme has evolved whereby tyrosine hydroxylase activity is modulated by nearly every documented form of regulation. Beginning with the genomic DNA, evidence exists for the transcriptional regulation of tyrosine hydroxylase mRNA levels, alternative RNA processing, and the regulation of RNA stability. There is also experimental support for the role of both translational control and enzyme stability in establishing steady-state levels of active tyrosine hydroxylase protein. Finally, mechanisms have been proposed for feedback inhibition of the enzyme by catecholamine products, allosteric modulation of enzyme activity, and phosphorylation-dependent activation of the enzyme by various different kinase systems. Given the growing literature suggesting that different tissues regulate tyrosine hydroxylase mRNA levels and activity in different ways, regulatory mechanisms provide not only redundancy but also diversity in the control of catecholamine biosynthesis.
677 citations
TL;DR: Data suggest that α-synuclein plays a role in the regulation of dopamine biosynthesis, acting to reduce the activity of tyrosine hydroxylase.
Abstract: The α-synuclein gene is implicated in the pathogenesis of Parkinson's disease. Although α-synuclein function is uncertain, the protein has homology to the chaperone molecule 14-3-3. In addition, α-synuclein can bind to 14-3-3, and both α-synuclein and 14-3-3 bind to many of the same proteins. Because 14-3-3 binds to and activates tyrosine hydroxylase, the rate-limiting enzyme in dopamine (DA) biosynthesis, we explored whether α-synuclein also bound to tyrosine hydroxylase and influenced its activity. Immunoprecipitation revealed an interaction between α-synuclein and tyrosine hydroxylase in brain homogenates and MN9D dopaminergic cells. Colocalization of α-synuclein with tyrosine hydroxylase was confirmed by immunoelectron microscopy. To explore the consequences of the interaction, we measured the effect of recombinant α-synuclein on tyrosine hydroxylase activity in a cell-free system and observed a dose-dependent inhibition of tyrosine hydroxylase by α-synuclein. To measure the impact of α-synuclein on tyrosine hydroxylase in dopaminergic cells, we stably transfected MN9D cells with wild-type or A53T mutant α-synuclein. Overexpression of wild-type or A53T mutant α-synuclein did not significantly alter tyrosine hydroxylase protein levels in our stably transfected cells. However, overexpressing cell lines had significantly reduced tyrosine hydroxylase activity and a corresponding reduction in dopamine synthesis. The reduction in cellular dopamine levels was not caused by increased dopamine catabolism or dopamine efflux. These data suggest that α-synuclein plays a role in the regulation of dopamine biosynthesis, acting to reduce the activity of tyrosine hydroxylase. If so, a loss of soluble α-synuclein, by reduced expression or aggregation, could increase dopamine synthesis with an accompanying increase in reactive dopamine metabolites.
TL;DR: KPC412 is a potent inhibitor of mutant FLT3 and is a candidate for testing as an antileukemia agent in AML patients with mutantFLT3 receptors.
TL;DR: This chapter reviews some of the critical substrates of these PTKs, the adapter proteins that, following phosphorylation on tyrosine residues, serve as binding sites for many of thecritical effector enzymes and other adapter proteins required for T cell activation.
Abstract: Engagement of the T cell antigen receptor (TCR) leads to a complex series of molecular changes at the plasma membrane, in the cytoplasm, and at the nucleus that lead ultimately to T cell effector function. Activation at the TCR of a set of protein tyrosine kinases (PTKs) is an early event in this process. This chapter reviews some of the critical substrates of these PTKs, the adapter proteins that, following phosphorylation on tyrosine residues, serve as binding sites for many of the critical effector enzymes and other adapter proteins required for T cell activation. The role of these adapters in binding various proteins, the interaction of adapters with plasma membrane microdomains, and the function of adapter proteins in control of the cytoskeleton are discussed.
TL;DR: It is demonstrated that Cbl additionally regulates epidermal growth factor (EGF) receptor endocytosis and uses a mechanism that is functionally separable from the ubiquitin ligase activity of Cbl to mediate ligand-dependent downregulation of receptor tyrosine kinases.
Abstract: Cbl is a multi-adaptor protein involved in ligand-induced downregulation of receptor tyrosine kinases. It is thought that Cbl-mediated ubiquitination of active receptors is essential for receptor degradation and cessation of receptor-induced signal transduction1,2,3,4,5. Here we demonstrate that Cbl additionally regulates epidermal growth factor (EGF) receptor endocytosis. Cbl rapidly recruits CIN85 (Cbl-interacting protein of 85K; ref. 6) and endophilins (regulatory components of clathrin-coated vesicles7,8,9,10) to form a complex with activated EGF receptors, thus controlling receptor internalization. CIN85 was constitutively associated with endophilins, whereas CIN85 binding to the distal carboxy terminus of Cbl was increased on EGF stimulation. Inhibition of these interactions was sufficient to block EGF receptor internalization, delay receptor degradation and enhance EGF-induced gene transcription, without perturbing Cbl-directed receptor ubiquitination. Thus, the evolutionary divergent C terminus of Cbl uses a mechanism that is functionally separable from the ubiquitin ligase activity of Cbl to mediate ligand-dependent downregulation of receptor tyrosine kinases.
TL;DR: It is suggested that Spry functions in a negative feedback mechanism in which its inhibitor activity is controlled rapidly and reversibly by post-translational mechanisms.
Abstract: Sprouty (Spry) inhibits signalling by receptor tyrosine kinases; however, the molecular mechanism underlying this function has not been defined. Here we show that after stimulation by growth factors Spry1 and Spry2 translocate to the plasma membrane and become phosphorylated on a conserved tyrosine. Next, they bind to the adaptor protein Grb2 and inhibit the recruitment of the Grb2–Sos complex either to the fibroblast growth factor receptor (FGFR) docking adaptor protein FRS2 or to Shp2. Membrane translocation of Spry is necessary for its phosphorylation, which is essential for its inhibitor activity. A tyrosine-phosphorylated octapeptide derived from mouse Spry2 inhibits Grb2 from binding FRS2, Shp2 or mouse Spry2 in vitro and blocks activation of the extracellular-signal-regulated kinase (ERK) in cells stimulated by growth factor. A non-phosphorylated Spry mutant cannot bind Grb2 and acts as a dominant negative, inducing prolonged activation of ERK in response to FGF and promoting the FGF-induced outgrowth of neurites in PC12 cells. Our findings suggest that Spry functions in a negative feedback mechanism in which its inhibitor activity is controlled rapidly and reversibly by post-translational mechanisms.
TL;DR: It is shown that in native cardiac cells and heterologous expression systems, Gαq-linked receptors or tyrosine kinase receptors that activate PLC potently inhibit channel activity.
Abstract: TRPM7 (ChaK1, TRP-PLIK, LTRPC7) is a ubiquitous, calcium-permeant ion channel that is unique in being both an ion channel and a serine/threonine kinase. The kinase domain of TRPM7 directly associates with the C2 domain of phospholipase C (PLC). Here, we show that in native cardiac cells and heterologous expression systems, Gαq-linked receptors or tyrosine kinase receptors that activate PLC potently inhibit channel activity. Numerous experimental approaches demonstrated that phosphatidylinositol 4,5-bisphosphate (PIP2), the substrate of PLC, is a key regulator of TRPM7. We conclude that receptor-mediated activation of PLC results in the hydrolysis of localized PIP2, leading to inactivation of the TRPM7 channel.
TL;DR: Signal transduction from activated c-Met to MEK and Erk required the presence of the cytoplasmic tail of CD44 including a binding motif for ERM proteins, which suggests a role forERM proteins and possibly their link to the cortical actin cytoskeleton in signal transfer.
Abstract: The tyrosine kinase receptor c-Met and its ligand HGF/SF, ezrin, and splice variants of CD44 have independently been identified as tumor metastasis-associated proteins. We now show that these proteins cooperate. A CD44 isoform containing variant exon v6 sequences is strictly required for c-Met activation by HGF/SF in rat and human carcinoma cells, in established cell lines as well as in primary keratinocytes. CD44v6-deficient tumor cells were unable to activate c-Met unless they were transfected with a CD44v6-bearing isoform. Antibodies to two v6-encoded epitopes inhibited autophosphorylation of c-Met by interfering with the formation of a complex formed by c-Met, CD44v6, and HGF/SF. In addition, signal transduction from activated c-Met to MEK and Erk required the presence of the cytoplasmic tail of CD44 including a binding motif for ERM proteins. This suggests a role for ERM proteins and possibly their link to the cortical actin cytoskeleton in signal transfer.
TL;DR: It is demonstrated that CEP-701 induces a cytotoxic effect on cells in a dose-responsive fashion that parallels the inhibition of FLT3, and form the basis for a planned clinical trial of the indolocarbazole derivative Cep-701 in patients with AML harboringFLT3- activating mutations.
TL;DR: In epithelial cells, Semaphorin 4D (Sema 4D) triggers invasive growth, a complex programme that includes cell–cell dissociation, anchorage-independent growth and branching morphogenesis, and the involvement of an unexpected signalling mechanism, namely, the coupling of a plexin to a tyrosine kinase receptor.
Abstract: Semaphorins are cell surface and soluble signals that control axonal guidance1,2. Recently, semaphorin receptors (plexins) have been discovered and shown to be widely expressed3,4,5. Their biological activities outside the nervous system and the signal transduction mechanism(s) they utilize are largely unknown. Here, we show that in epithelial cells, Semaphorin 4D (Sema 4D) triggers invasive growth, a complex programme that includes cell–cell dissociation, anchorage-independent growth and branching morphogenesis6. Interestingly, the same response is also controlled by scatter factors through their tyrosine kinase receptors, which share striking structural homology with plexins in their extracellular domain 3. We found that in cells expressing the endogenous proteins, Plexin B1 (the Sema 4D Receptor) and Met (the Scatter Factor 1/ Hepatocyte Growth Factor Receptor) associate in a complex. In addition, binding of Sema 4D to Plexin B1 stimulates the tyrosine kinase activity of Met, resulting in tyrosine phosphorylation of both receptors. Finally, cells lacking Met expression do not respond to Sema 4D unless exogenous Met is expressed. This work identifies a novel biological function of semaphorins and suggests the involvement of an unexpected signalling mechanism, namely, the coupling of a plexin to a tyrosine kinase receptor.
TL;DR: Inhibition of complex formation is sufficient to block HGF receptor internalization and to enhance HGF-induced signal transduction and biological responses, and disclose a novel functional role for Cbl in HGF receptors signalling.
Abstract: Ligand-dependent downregulation of tyrosine kinase receptors is a critical step for modulating their activity. Upon ligand binding, hepatocyte growth factor (HGF) receptor (Met) is polyubiquitinated and degraded; however, the mechanisms underlying HGF receptor endocytosis are not yet known. Here we demonstrate that a complex involving endophilins, CIN85 and Cbl controls this process. Endophilins are regulatory components of clathrin-coated vesicle formation. Through their acyl-transferase activity they are thought to modify the membrane phospholipids and induce negative curvature and invagination of the plasma membrane during the early steps of endocytosis. Furthermore, by means of their Src-homology 3 domains, endophilins are able to bind CIN85, a recently identified protein that interacts with the Cbl proto-oncogene. Cbl, in turn, binds and ubiquitinates activated HGF receptor, and by recruiting the endophilin-CIN85 complex, it regulates receptor internalization. Inhibition of complex formation is sufficient to block HGF receptor internalization and to enhance HGF-induced signal transduction and biological responses. These data provide further evidence of a relationship between receptor-mediated signalling and endocytosis, and disclose a novel functional role for Cbl in HGF receptor signalling.
TL;DR: It is inferred that signaling from the ErbB2 receptor, which is enriched in T-tubules in cardiomyocytes, is crucial for adult heart function.
Abstract: The ErbB2 (Her2) proto-oncogene encodes a receptor tyrosine kinase, which is frequently amplified and overexpressed in human tumors. ErbB2 provides the target for a novel and effective antibody-based therapy (Trastuzumab/Herceptin) used for the treatment of mammary carcinomas. However, cardiomyopathies develop in a proportion of patients treated with Trastuzumab, and the incidence of such complications is increased by combination with standard chemotherapy. Gene ablation studies have previously demonstrated that the ErbB2 receptor, together with its coreceptor ErbB4 and the ligand Neuregulin-1, are essential for normal development of the heart ventricle. We use here Cre-loxP technology to mutate ErbB2 specifically in ventricular cardiomyocytes. Conditional mutant mice develop a severe dilated cardiomyopathy, with signs of cardiac dysfunction generally appearing by the second postnatal month. We infer that signaling from the ErbB2 receptor, which is enriched in T-tubules in cardiomyocytes, is crucial for adult heart function. Conditional ErbB2 mutant mice provide a model of dilated cardiomyopathy. In particular, they will allow a rigorous assessment of the role of ErbB2 in the heart and provide insight into the molecular mechanisms that underlie the adverse effects of anti-ErbB2 antibodies.
TL;DR: Most of the RTKs activated at the cell surface showed interaction with PTP1B after internalization, establishing that RTK activation and inactivation are spatially and temporally partitioned within cells.
Abstract: When bound by extracellular ligands, receptor tyrosine kinases (RTKs) on the cell surface transmit critical signals to the cell interior. Although signal termination is less well understood, protein tyrosine phosphatase–1B (PTP1B) is implicated in the dephosphorylation and inactivation of several RTKs. However, PTP1B resides on the cytoplasmic surface of the endoplasmic reticulum (ER), so how and when it accesses RTKs has been unclear. Using fluorescence resonance energy transfer (FRET) methods, we monitored interactions between the epidermal- and platelet-derived growth factor receptors and PTP1B. PTP1B-catalyzed dephosphorylation required endocytosis of the receptors and occurred at specific sites on the surface of the ER. Most of the RTKs activated at the cell surface showed interaction with PTP1B after internalization, establishing that RTK activation and inactivation are spatially and temporally partitioned within cells.
TL;DR: C-Met when mutated or over-expressed in malignant cells serves as an important therapeutic target and the most recent data in terms of inhibition of c-Met and downstream signal transduction pathways is summarized.
TL;DR: Electron microscopy studies of hrs mutant larvae reveal an impairment in endosome membrane invagination and formation of multivesicular bodies (MVBs), and data suggest that Hrs and MVB formation function to downregulate TKR signaling.
TL;DR: It is proposed that the nucleus represents a site for ERK action, sequestration and signal termination in the MAPK cascade, and it is illustrated that besides controlling cell proliferation the ERK cascade also controls cell differentiation and cell behaviour.
TL;DR: It is suggested that three functional properties—activator insufficiency, cooperative activation, and default repression—are shared among the major pathways and allow signaling pathways to strongly activate target genes in their proper context, while preventing their expression in all other cells.
Abstract: Seven major cell–cell signaling pathways—Wnt, TGF, Hedgehog (Hh), receptor tyrosine kinase (RTK), nuclear receptor, Jak/STAT, and Notch—control the vast majority of cell fate decisions during the development of bilaterian animals (Gerhart 1999). Each pathway is used repeatedly during the development of a given organism, activating different subsets of target genes in different developmental contexts. These seven pathways are strikingly diverse in both their complexity and the biochemical mechanism of signal transduction, ranging from direct transcriptional regulation by the nuclear receptor proteins to the extended protein phosphorylation cascades characteristic of RTK pathways. Nevertheless, the primary consequence of signaling is the same: activation of specific target genes by signal-regulated transcription factors. Recent work has revealed several surprising and fundamental commonalities in the transcriptional mechanisms by which these pathways control the expression of their target genes. In this review, we discuss transcriptional regulation by developmental cell signaling pathways, and suggest that three functional properties—activator insufficiency, cooperative activation, and default repression—are shared among the major pathways. Together, these three “habits” allow signaling pathways to strongly activate target genes in their proper context, while preventing their expression in all other cells. Such strict control over target gene expression explains an extraordinary feature of developmental cell signaling: the capacity of a single pathway to elicit a large variety of gene expression patterns, and hence to control the specification of a large variety of cell fates.
TL;DR: It is shown that the chaperone-binding ubiquitin ligase CHIP efficiently ubiquitinates and down-regulates ErbB2, and a previously unrecognized pathway, amenable to pharmacologic manipulation, that mediates Erb B2 stability is described.
Abstract: Overexpression of the transmembrane receptor tyrosine kinase ErbB2 is common in multiple malignancies, including breast and ovarian cancer. ErbB2 is resistant to degradation mediated by c-Cbl, the E3 ubiquitin ligase responsible for ligand-induced ubiquitination of ErbB1 (epidermal growth factor receptor). Because of its resistance to degradation, ErbB2 is the preferred dimerization partner for other members of the ErbB family, and its overexpression in vivo is associated with poor prognosis. We now show that the chaperone-binding ubiquitin ligase CHIP efficiently ubiquitinates and down-regulates ErbB2. CHIP expression shortens the half-life of both nascent and mature ErbB2 protein. In vitro ubiquitination assay shows that CHIP serves as a ubiquitin ligase for ErbB2, and both exogenously expressed and endogenous CHIP coprecipitate with the kinase. Furthermore, CHIP association with ErbB2 requires a chaperone intermediate and is increased by the chaperone-binding drug geldanamycin, a potent stimulator of ErbB2 ubiquitination and degradation. These data describe a previously unrecognized pathway, amenable to pharmacologic manipulation, that mediates ErbB2 stability.
TL;DR: This review will weigh an increasing body of literature implicating the intermediate signaling pathway consisting of MEK1 and extracellular signal-regulated kinases (ERK1/2) as important regulators of cardiac hypertrophy and myocyte survival.
Abstract: In response to pathophysiological stress, the adult heart undergoes hypertrophic enlargement characterized by an increase in the cross-sectional area of individual myofibers Although cardiac hypertrophy is initially a compensatory response, sustained hypertrophy is a leading predictor for the development of heart failure At the molecular level, disease-related stimuli invoke endocrine, paracrine, and autocrine regulatory circuits, which directly influence cardiomyocyte hypertrophy, in part, through membrane bound G protein-coupled receptors and receptor tyrosine kinases These membrane receptors activate intermediate signal transduction pathways within the cytoplasm such as mitogen-activated protein kinases (MAPKs), protein kinase C (PKC), and calcineurin, which directly modify transcriptional regulatory factors promoting alterations in cardiac gene expression This review will weigh an increasing body of literature implicating the intermediate signaling pathway consisting of MEK1 and extracellular signal-regulated kinases (ERK1/2) as important regulators of cardiac hypertrophy and myocyte survival The MEK1-ERK1/2 pathway likely occupies a central regulatory position in the signaling hierarchy of a cardiac myocyte given its unique ability to respond to virtually every characterized hypertrophic agonist and stress stimuli examined to date and based on its ability to promote myocyte growth in vitro and in vivo
TL;DR: In this paper, the involvement of reactive oxygen species (ROS) in the mitogenic cascade initiated by the tyrosine kinase receptors of several growth factor peptides was investigated.
TL;DR: Based upon its clear association with disease, the Bcr-Abl tyrosine kinase in CML represents the ideal target to validate the clinical utility of protein kinase inhibitors as therapeutic agents.