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

---

Query: EC:2.7.10.2 (focal adhesion kinase)
44,029 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

About 10% of patients with essential thrombocythemia (ET) or myelofibrosis (MF) that lack mutations in JAK2 harbor an activating mutation in the thrombopoietin receptor, MPLW515L. Distinct from the JAK2V617F retroviral transplant model, the MPLW515L model recapitulates many features of ET and MF, including severe fibrosis and thrombocytosis. We have tested EXEL-8232, an experimental potent JAK2 inhibitor, for efficacy in suppression of thrombocytosis in vivo and for its ability to attenuate MPLW515L myeloproliferative disease. EXEL-8232 was administered for 28 days q12 h by oral gavage at doses of 30 or 100 mg/kg, prospectively. Animals treated with EXEL-8232 at 100 mg/kg had normalized high platelet counts, eliminated extramedullary hematopoiesis in the spleen and eliminated bone marrow fibrosis, whereas the wild-type controls did not develop thrombocytopenia. Consistent with a clinical response in this model, we validated surrogate end points for response to treatment, including a reduction of endogenous colony growth and signaling inhibition in immature erythroid and myeloid primary cells both in vitro and upon treatment in vivo. We conclude that EXEL-8232 has efficacy in treatment of thrombocytosis in vivo in a murine model of ET and MF, and may be of therapeutic benefit for patients with MPL-mutant MPN.
...
PMID:EXEL-8232, a small-molecule JAK2 inhibitor, effectively treats thrombocytosis and extramedullary hematopoiesis in a murine model of myeloproliferative neoplasm induced by MPLW515L. 2200 86

Recent clinical trials with JAK or mammalian target of rapamycin (mTOR) inhibitors in primary myelofibrosis (PMF) have identified pruritus as one of the most treatment-responsive disease traits. However, little is known about the prevalence of pruritus in PMF or its clinical and laboratory correlates. Among 566 consecutive patients with PMF seen at our institution, the presence or absence of pruritus was documented in 90 (16%) and 146 (26%) patients, respectively. Patients with pruritus were less likely to express MPLW515 (0% vs. 10%; P = 0.02) or leukopenia (8% vs. 24%; P = 0.002). The latter association was more pronounced in the absence of JAK2 or MPL mutations. Pruritus also clustered with marked leukocytosis (23% vs. 11%; P = 0.01) and JAK2V617F (71% vs. 59%; P = 0.08). Pruritus did not correlate with karyotype (P = 0.33), risk category per the Dynamic International Prognostic Scoring System (DIPSS)-plus (P = 0.37), DIPSS-plus-adjusted survival (P = 0.41), or leukemic transformation (P = 0.13). Plasma levels of 20 cytokines, which are known to be abnormally expressed in PMF, including IL-1b, IL-2R, IL-6, IL-8, and VEGF, were measured in 63 informative cases and showed no correlations with history of pruritus. We conclude that pruritus is relatively frequent in PMF and is prognostically irrelevant. The pathogenesis of PMF-associated pruritus is not necessarily linked to proinflammatory cytokines but may instead involve molecules that are either granulocyte-derived or influence granulopoiesis. The apparently differential effect of MPL vs. JAK2 mutations on pruritus requires further investigation.
...
PMID:Pruritus in primary myelofibrosis: clinical and laboratory correlates. 2208 34

The classification and diagnostic criteria of the myeloproliferative neoplasms have changed significantly in the 2008 World Health Organization monograph on the classification of hematologic malignancies. Many of the changes arose from the findings that the different malignancies are associated with abnormal cell signaling because of translocations or mutations in genes for protein tryosine kinases involved in the normal growth and regulation of hematopoietic cells. These include ABL1, PDGFRA, PDGFRB, FGFR1, JAK2, MPL, and KIT. The new classification attempts to reflect the related molecular pathogenesis of the different entities and incorporates the identification of the molecular defects into the diagnostic criteria for some of the individual diseases. Issues concerning the new classification are discussed, and the new diagnostic criteria are reviewed and commented upon.
...
PMID:The myeloproliferative neoplasms including the eosinophilia-related myeloproliferations associated with tyrosine kinase mutations: changes and issues in classification and diagnosis criteria. 2219 8

Sixty-four patients < 20 years of age, investigated for a suspicion of Philadelphia-negative myeloproliferative disease (MPD), were retrospectively evaluated to characterize the different forms and to examine the treatments used and long-term outcome. JAK2 mutations, endogenous erythroid colony growth, and clonality were investigated in 51 children. Mutations of thrombopoietin, the thrombopoietin receptor (MPL), and the erythropoietin receptor and mutations of other genes involved in the pathogenesis of MPD were investigated in JAK2 wild-type patients. Based on our criteria for childhood MPD, we identified 34 patients with sporadic thrombocythemia (ST), 16 with hereditary thrombocytosis (HT), 11 with sporadic polycythemia (SP), and 3 with hereditary polycythemia (HP). JAK2(V617F) mutations were present in 47.5% of ST and in no HT. The MPL(S505A) mutation was detected in 15/16 HT patients and in no ST (P < .00001). The JAK2(V617F) mutation occurred in 27% of SP patients diagnosed according to the Polycythemia Vera Study Group or World Health Organization 2001 criteria. Children with ST received more cytoreductive drugs than those with HT (P = .0006). After a median follow-up of 124 months, no patient had developed leukemia or myelofibrosis and 5% had thrombosis; the miscarriage rate in thrombocythemic patients was 14%. The low complication rate in our population suggests that children with MPD may be managed by tailored approaches.
...
PMID:Thrombocythemia and polycythemia in patients younger than 20 years at diagnosis: clinical and biologic features, treatment, and long-term outcome. 2226 73

Myeloproliferative neoplasms (MPNs) are clonal disorders characterized by excessive production of mature cells. In most of the classic Philadelphia-negative MPNs-polycythemia vera (PV), essential thrombocythemia (ET), and MPN-associated myelofibrosis (MPN-MF)-oncogenic mutations affecting JAK2 or MPL lead to constitutive activation of cytokine-regulated intracellular signalling pathways. The traditional therapy for PV and ET is the prevention of thrombotic events with antiproliferative agents in association with aspirin. New drugs such as pegylated interferon and anti-JAK agents are candidates for slowing the evolution to myelofibrosis or leukemia. Conventional therapy for MPN-MF is driven by clinical needs, primarily anemia and splenomegaly. Lenalidomide and pomalidomide are new candidates for treating anemia. JAK2 ATP-competitive inhibitors or drugs that indirectly inhibit the JAK-STAT pathway, like RAD001, are the new candidates for splenomegaly in MPN-MF, but in spite of their strong rationale, they have shown only a palliative benefit. Allogeneic stem cell transplantation remains the only potentially curative approach.
...
PMID:Management of myeloproliferative neoplasms: from academic guidelines to clinical practice. 2227 47

Essential thrombocythemia (ET) is a rare type of myeloproliferative neoplasm characterized by clonal expansion of the megakaryocyte and platelet lineage. Here, we describe a novel mutation (Y252H) in the thrombopoietin (TPO) receptor, or MPL, in a JAK2 mutation-negative ET patient. The bone marrow examination revealed increased numbers of dysmorphic megakaryocytes with focal clustering. The x-inactivation pattern suggested clonal expansion of hematopoietic cells in the bone marrow. Furthermore, we found that the patient's bone marrow cells were hypersensitive to TPO in generating megakaryocyte colonies in vitro. More importantly, we demonstrated that this MPL Y252H mutant confers increased TPO/MPL-mediated cell growth and increased cell survival upon cytokine withdrawal in BaF3 cells, indicating it is a disease-driving mutation and may contribute to the development of ET in vivo. In summary, this is the first report describing a mutation in the extracellular domain of MPL underlying ET.
...
PMID:A novel mutation in MPL (Y252H) results in increased thrombopoietin sensitivity in essential thrombocythemia. 2238 68

Since the discovery of the JAK2V617F tyrosine kinase-activating mutation several genes have been found mutated in nonchronic myeloid leukemia (CML) myeloproliferative neoplasms (MPNs), which mainly comprise three subtypes of "classic" MPNs; polycythemia vera (PV), essential thrombocythemia (ET), and myelofibrosis (MF). We searched for mutations in ASXL1, CBL, DNMT3A, IDH1, IDH2, JAK2, MPL, NF1, SF3B1, SUZ12, and TET2 genes in 149 non-CML MPNs, including 127 "classic" MPNs cases. JAK2 was mutated in 100% PV, 66% ET and 68% MF. We found a high incidence of ASXL1 mutation in MF patients (20%) and a low incidence in PV (7%) and ET (4%) patients. Mutations in the other genes were rare (CBL, DNMT3A, IDH2, MPL, SF3B1, SUZ12, NF1) or absent (IDH1).
...
PMID:Mutation analysis of ASXL1, CBL, DNMT3A, IDH1, IDH2, JAK2, MPL, NF1, SF3B1, SUZ12, and TET2 in myeloproliferative neoplasms. 2248 43

We investigated 15,542 patients with suspected BCR-ABL1- negative myeloproliferative or myelodysplastic/myeloproliferative neoplasm (including 359 chronic myelomonocytic leukemia) by a molecular marker set. JAK2V617F was detected in the suspected categories as follows: polycythemia vera 88.3%, primary myelofibrosis 53.8%, essential thrombocythemia 50.2%, and not further classifiable myeloproliferative neoplasms 38.0%. JAK2 exon 12 mutations were detected in 40.0% JAK2V617F-negative suspected polycythemia vera, MPLW515 mutations in 13.2%JAK2V617F-negative primary myelofibrosis and 7.1% JAK2V617F-negative essential thrombocythemia. TET2 mutations were distributed across all entities but were most frequent in suspected chronic myelomonocytic leukemia (77.8%). CBL mutations were identified in suspected chronic myelomonocytic leukemia (13.9%), primary myelofibrosis (8.0%), and not further classifiable myeloproliferative neoplasm (7.0%). This leads to a stepwise workflow for suspected myeloproliferative neoplasms starting with JAK2V617F and investigating JAK2V617F-negative patients for JAK2 exon 12 or MPL mutations, respectively. In cases in which a myeloproliferative neoplasm cannot be established, analysis for TET2, CBL and EZH2 mutations may be indicated.
...
PMID:Molecular analyses of 15,542 patients with suspected BCR-ABL1-negative myeloproliferative disorders allow to develop a stepwise diagnostic workflow. 2251 94

JAK2 (V617F) is associated with a genetic predisposition to its acquisition,as it is preferentially found in subjects with a common constitutional JAK2 haplotype known as 46/1 or GGCC. A recent study suggests that a genetic predisposition to acquisition of MPL mutation may exist in sporadic patients, since an association was found with the JAK2 46/1 haplotype. We genotyped 509 patients with myeloproliferative neoplasms (MPN), 7% of which carrying a somatic mutation of MPL Exon 10. We found that the JAK2 GGCC haplotype was closely associated with JAK2 (V617F) (OR 1.84, P < 0.001) but not with MPL mutations (OR 0.98), suggesting a different genetic background for these molecular lesions.
...
PMID:JAK2 GGCC haplotype in MPL mutated myeloproliferative neoplasms. 2256 17

In 2008, the World Health Organization (WHO) revised the classification system for myeloproliferative neoplasms (MPNs). MPNs include chronic myelogenous leukemia, essential thrombocythemia, polycythemia vera, primary myelofibrosis, and several other disorders. The newer classification system incorporates mutations discovered in the JAK2 and MPL genes. The importance of understanding the role of mutations in JAK2, MPL, and other genes that have been discovered in MPNs is highlighted by the change in the 2008 WHO MPN classification system. Moreover, the development of highly specific inhibitors of JAK2 further stresses the importance of molecular testing in MPN diagnosis and prognosis.
...
PMID:Pathology consultation on myeloproliferative neoplasms. 2270 52


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>

---