Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:2.7.10.1 (ERK)
95,504 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Defibrotide (DF) is a mixture of porcine-derived single-stranded phosphodiester oligonucleotides (9-80-mer; average, 50-mer) that has been successfully used to treat severe hepatic veno-occlusive disease (sVOD) with multiorgan failure (MOF) in patients who have received cytotoxic chemotherapy in preparation for bone marrow transplantation. However, its mechanism of action is unknown. Herein, we show that DF and phosphodiester oligonucleotides can bind to heparin-binding proteins (eg, basic fibroblast growth factor [bFGF] but not vascular endothelial growth factor [VEGF] 165) with low nanomolar affinity. This binding occurred in a length- and concentration-dependent manner. DF can mobilize proangiogenic factors such as bFGF from their depot or storage sites on bovine corneal endothelial matrix. However, these molecules do not interfere with high-affinity binding of bFGF to FGFR1 IIIc but can replace heparin as a required cofactor for binding and hence cellular mitogenesis. DF also protects bFGF against digestion by trypsin and chymotrypsin and from air oxidation. In addition, DF binds to collagen I with low nanomolar affinity and can promote human microvascular endothelial cell-1 (HMEC-1) cell mitogenesis and tubular morphogenesis in three-dimensional collagen I gels. Thus, our data suggest that DF may provide a stimulus to the sinusoidal endothelium of a liver that has suffered a severe angiotoxic event, thus helping to ameliorate the clinical sVOD/MOF syndrome.
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PMID:Angiogenesis alteration by defibrotide: implications for its mechanism of action in severe hepatic veno-occlusive disease. 1917 63

In the World Health Organization classification, one major and four minor criteria are specified for the diagnosis of systemic mastocytosis. We report our experience using these criteria to diagnose systemic mastocytosis involving bone marrow. A total of 59 patients with clinically suspected systemic mastocytosis underwent comprehensive bone marrow examination, including immunophenotyping by immunohistochemistry and/or flow cytometry and molecular studies for KIT exon 17 mutations. Serum tryptase levels were also assessed. Of these 59, 53 (90%) patients met the diagnostic criteria for systemic mastocytosis. In these patients, multifocal dense infiltrates of mast cells, the major criterion, was observed in 36 (68%) patients. Atypical mast cell morphology was observed in 53 (100%), an aberrant immunophenotype was identified in 50 of 52 (96%), KIT mutation was present in 33 of 44 (75%), and an elevated serum tryptase (>20 ng/ml) was detected in 44 of 52 (85%). In the six patients in which bone marrow examination could not confirm systemic mastocytosis, one had systemic mastocytosis involving spleen, one patient had chronic idiopathic myelofibrosis, and four had no specific diagnosis, but systemic mastocytosis was still considered most likely. Of these six patients, atypical mast cell morphology was identified in five, aberrant immunophenotype in five, KIT mutation in two, and elevated serum tryptase in two. None of these cases met the major criteria. We conclude that the World Health Organization criteria are useful for the diagnosis of systemic mastocytosis in bone marrow specimens. The results also show the relative values of traditional morphologic criteria (ie, major criterion) and the results of ancillary testing (ie, minor criteria). However, as illustrated by the case of splenic systemic mastocytosis as well as the patient with chronic idiopathic myelofibrosis, the current World Health Organization system is neither completely sensitive nor specific for systemic mastocytosis.
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PMID:Utility of the World Heath Organization classification criteria for the diagnosis of systemic mastocytosis in bone marrow. 1911 30

Human tryptase is a serine protease expressed in mast-cells. We previously observed that AML blast cells, cultured in vitro from a KIT D816Y patient, give rise to adherent cells with mast-cell like phenotype and tryptase was released in the serum-free medium. To correlate total serum tryptase (ts-try) levels with cytogenetic features and KIT mutational status, we analyzed serum samples from AML patients at diagnosis. In 70 out of 155 patients (45%) we detected elevated ts-try (>15 ng/mL), significantly linked to t(8;21) (P < .001) and inv(16) (P = .007). In patients that achieved complete remission the ts-try decreased to normal values. In 75 patients screened for KIT mutation, we found a clear relationship between elevated ts-try and mutated patients with t(8;21) (P < .001). In conclusion, we propose that checking for ts-try at diagnosis of AML may be a simple tool to select patients to be addressed to KIT mutation screening.
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PMID:Total serum tryptase: a predictive marker for KIT mutation in acute myeloid leukemia. 1940 74

GM-CSF has been showed to be able to induce up-regulated receptor and cytokine expression in mast cells in inflammatory conditions. However, little is known of its effects on protease activated receptor (PAR) expression and Th2 cytokine secretion from mast cells. In the present study, we examined potential influence of GM-CSF on mast cell PAR expression and IL-4 and IL-10 release by using flow cytometry analysis, quantitative real time PCR, ELISA and cellular activation of signaling ELISA (CASE) techniques. The results showed that GM-CSF induced up to 3.0-fold increase in IL-4 release from P815 cells, and FSLLRY-NH(2) and trans-cinnamoyl (tc)-YPGKF-NH(2) did not affect GM-CSF induced IL-4 release. GM-CSF reduced tryptase and trypsin induced IL-4 release by up to approximately 55.8% and 70.3%, respectively. GM-CSF elicited the upregulated expression of PAR-1, PAR-2, PAR-3 and PAR-4 mRNAs, but enhanced only PAR-4 protein expression in P815 cells. U0126, PD98059 and LY204002 almost completely abolished GM-CSF induced IL-4 release when they were preincubated with P815 cells for 30 min, indicating ERK and Akt cell signaling pathways may be involved in the event. In conclusion, GM-CSF can stimulate IL-4 release from mast cells through an ERK and Akt cell signaling pathway dependent, but PAR independent mechanism. GM-CSF may serve as a regulator for IL-4 production in mast cells and through which participates in the mast cell related inflammation.
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PMID:Induction of IL-4 release and upregulated expression of protease activated receptors by GM-CSF in P815 cells. 1965 24

Mastocytosis, an unusual disorder of bone marrow-derived, clonally transformed hematopoietic progenitor cells, exhibits a broad spectrum of clinical and morphologic features ranging from a self-limiting benign disorder (ie, juvenile cutaneous mastocytosis) to highly aggressive neoplasms like mast cell leukemia. Principally, mastocytosis should be divided in 2 main subentities: cutaneous mastocytosis and systemic mastocytosis mainly involving the bone marrow. Mastocytosis is a morphologic diagnosis and should not be diagnosed on the basis of clinical findings alone. Pathologists need to be aware of the disease and its mimickers. Application of the defined diagnostic criteria can confirm or exclude mastocytosis in most cases. Use of antibodies against tryptase, CD117 (KIT), and CD25 is recommended in every suspected case. Because most cases of systemic mastocytosis show a very low degree of infiltration of the bone marrow, antitryptase and anti-CD117 are of major importance for screening and quantification of mast cells, in particular to detect even small compact infiltrates as the only major diagnostic criterion for mastocytosis. Expression of CD25 on mast cells is defined as a minor diagnostic criterion and is usually seen only in mastocytosis but not in reactive states of mast cell hyperplasia.
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PMID:Mastocytosis: an unusual clonal disorder of bone marrow-derived hematopoietic progenitor cells. 1968 20

A small subgroup of patients with hypereosinophilic syndrome (HES) demonstrates imatinib-sensitive fusion transcript-the FIP1L1-PDGFRA (F/P+). These cases are currently diagnosed as chronic eosinophilic leukaemia (CEL). In this paper, we screened 77 patients to estimate the frequency of FIP1L1-PDGFRA transcript among patients with unexplained, long-term hypereosinophilia exceeding 1.5 x 10(9)/L and to analyse the clinical and serological features in F/P+ CEL population. The FIP1L1-PDGFRA chimeric protein was detectable in 16 (14 males and 2 females) out of 77 examined HES patients (20%) by RT-PCR. Two patients suffered from cough at diagnosis. Three out of 16 (18%) patients had no organ involvements, in 5-one organ was affected and in the remaining eight cases-at least two. Eosinophilic organ damage/dysfunction identified splenomegaly in the majority of studied patients. We compared clinical and serological features between CEL F/P+ (n = 16) and HES (n = 61) patients. F/P+ cases had significantly increased WBC and absolute eosinophil count (AEC) at diagnosis (p = 0.008 and 0.02), whereas platelet count was decreased in this population (p = 0.03). Serum B12 and tryptase levels were increased (p = 0.002 and 0.004) in CEL F/P+ patients when compared to HES cases whereas serum IL-5 levels were significantly increased in the latter group (p = 0.01). Male gender and splenomegaly occurred more frequent in CEL F/P+ population (p = 0.002 and 0.0007, respectively). Additionally, patients with F/P+ CEL (n = 16) were compared with F/P- CEL (n = 8). The latter group, was significantly older, had lower AEC and higher platelet count. In conclusion, significant clinical symptoms are infrequent present and splenomegaly remains the most common organ involvement in patients with CEL expressing F/P fusion transcript. Our study confirmed the long-term remission on imatinib in this patient population.
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PMID:Clinical characteristics of patients with chronic eosinophilic leukaemia (CEL) harbouring FIP1L1-PDGFRA fusion transcript--results of Polish multicentre study. 1972 96

In this study we examined the potential for PAR(2) and TNFalpha to synergise at the level of MAP kinase signalling in PAR(2) expressing NCTC2544 cells. However, to our surprise we found that activation of PAR(2) by trypsin or the specific activating peptide SLIGKV-OH strongly inhibited both the phosphorylation and activity of JNK. In contrast neither p38 MAP kinase nor ERK activation was affected although TNFalpha stimulated IkappaBalpha loss was partially reversed. The inhibitory effect was not observed in parental cells nor in cells expressing PAR(4), however inhibition was reversed by pre-incubation with the novel PAR(2) antagonist K14585, suggesting that the effect is specific for PAR(2) activation. SLIGKV-OH was found to be more potent in inhibiting TNFalpha-induced JNK activation than in stimulating JNK alone, suggesting agonist-directed signalling. The PKC activator PMA, also mimicked the inhibitory effect of SLIGKV-OH, and the effects of both agents were reversed by pre-treatment with the PKC inhibitor, GF109203X. Furthermore, incubation with the novel G(q/11) inhibitor YM25480 also reversed PAR(2) mediated inhibition. Activation of PAR(2) was found to disrupt TNFR1 binding to RIP and TRADD and this was reversed by both GF109203X and YM25480. A similar mode of inhibition observed in HUVECs through PAR(2) or P2Y2 receptors demonstrates the potential of a novel paradigm for GPCRs linked to G(q/11), in mediating inhibition of TNFalpha-stimulated JNK activation. This has important implications in assessing the role of GPCRs in inflammation and other conditions.
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PMID:Proteinase-activated receptor-2 mediated inhibition of TNFalpha-stimulated JNK activation - A novel paradigm for G(q/11) linked GPCRs. 1978 31

Although significant progresses were made in the field of molecular biology of malignant cerebral gliomas, the prognostic of these tumors continues to be reserved. One of the therapeutic failure reasons is the incomplete knowledge regarding the origin of these tumors and cells features, which in fact represent an obstacle in developing a cell and molecular therapy guided against malignant cells responsible for the tumor development and for the therapeutic resistance. Initiation and characterization of glioblastoma cell lines represents an essential step in order to obtain a better in vitro and in vivo experimental model for glioblastoma. We describe here a new glioblastoma line, named T11, which was successfully isolated in our laboratories starting with a tumor sample obtained intraoperative from a 58 years-old female patient. The histopathological evaluation showed a grad IV WHO glioma (glioblastoma). The sample was prepared by manual fragmentation, followed by enzymatic digestions using different concentration of trypsin. The cell line has been cultivated for more than 150 passages. The characterization of the glioblastoma line consisted in the evaluation of cells proliferation capacity (growth curve), morphological features, karyotyping and identification of specific markers. We found that T11 expressed specific markers for glial progenitors and astrocytes (glial fibrillary acidic protein-GFAP); oligodendrocites (A2B5; O4), and microglia (CD45, CD 11b). Cells were negative for neuronal lineage markers like beta3-tubulin and NCAM. In order to evaluate the differentiation grade of T11 cell line, the presence of stem cell markers (nestin, CD133) was explored. T11l cells expressed higher level of nestin and lower level of CD133 comparing with standard glioblastoma cell line U87. T11 cell line expressed VEGF and Bcl-2, but not EGFR and Mdrl and Bax. This new line has distinct and unique characteristics when compared with standard glioblastoma cell line (e.g., U87) and may become a new and useful in vitro model for glioblastoma.
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PMID:Isolation and partial characterization of a new human glioblastoma cell line. 1988 54

The role of protease-activated receptor (PARs) in the regulation of microglial activation process is increasingly evident. In the present study, we have investigated the role of PAR-2, which can be activated by trypsin-like proteases, in microglial activation and neuronal cell death. In cultured rat primary microglia, activation of PAR-2 induced nitrite production by PKC- and MAPKs-dependent mechanism. Among the three members of MAPK pathway, ERK and JNK but not p38 mediated PAR-2-induced microglial activation. The down-stream regulator of PAR-2-PKC-MAPK pathway-induced microglial activation was NF-kappaB pathway. Besides nitrite, PAR-2 activation increased production of a variety of inflammatory mediators such as ROS and pro-inflammatory cytokines including TNF-alpha and IL-1beta. The addition of culture spent media from PAR-2 activated microglia induced neuronal cell death in primary rat cortical neuron cultures with apoptotic features such as increased number of terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling-positive neurons, dissipation of mitochondrial membrane potential, increased expression of pro-apoptotic Bax, decreased expression of anti-apoptotic Bcl-2, Bcl-X(L), and activation of caspase-3 in neurons. Interestingly, the increased production of cytoactive molecules as well as the neuronal cell death was normalized by PAR-2 or trypsin inhibitor or an NO synthase inhibitor, N(G)-nitro-l-arginine-methyl ester. Taken together, these results suggest that overt PAR-2 activation may induce microglial activation, which contributes to neuronal cell death.
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PMID:Activation of microglial cells via protease-activated receptor 2 mediates neuronal cell death in cultured rat primary neuron. 1988 13

We describe a case of systemic mastocytosis associated with myelodysplastic syndrome. The bone marrow showed multifocal clusters of mast cells and myeloid dysplasia. Sequencing of the KIT DNA revealed a point mutation at codon 816 including a substitution of valine for aspartic acid (D816V). The patient's tumor did not respond to imatinib; however, interferon-alpha reduced the bone marrow mast cells and serum total tryptase. The patient remains alive at one year after the diagnosis without disease progression.
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PMID:Successful treatment of KIT D816V-positive, imatinib-resistant systemic mastocytosis with interferon-alpha. 1991 99


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