Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0023473 (chronic myeloid leukemia)
 18,916 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Tyrosine phosphorylation is important in the transmission of growth and differentiation signals; known tyrosine kinases include several oncoproteins and growth factor receptors. Interestingly, some differentiated cell types, such as erythrocytes and platelets contain high amounts of phosphotyrosine. We analyzed tyrosine kinases expressed in the K-562 chronic myelogenous leukemia cell line, which has a bipotential erythroid and megakaryoblastoid differentiation capacity. Analysis of 359 polymerase chain reaction-amplified cDNA clones led to the identification of 14 different tyrosine kinase-related sequences (JTK1-14). Two of the clones (JTK2 and JTK4) represent unusual members of the fibroblast growth factor receptor gene family, and the clones JTK5, JTK11, and JTK14 may also belong to the family of receptor tyrosine kinases but lack a close relationship to any known tyrosine kinase. Each of these different genes has its own characteristic expression pattern in K-562 cells and several other human tumor cell lines. In addition, the JTK11 and JTK14 mRNAs are induced during the megakaryoblastoid differentiation of K-562 cells. These tyrosine kinases may have a role in the differentiation of megakaryoblasts or in the physiology of platelets.
 ...
PMID:Putative tyrosine kinases expressed in K-562 human leukemia cells. 224 64

Janus Kinase 2 (JAK2) is a member of a family of four Janus Kinases, 2, and 3 and tyrosine kinase 2. Mutated JAK2 (V617F) has the ability to activate downstream signal transducer and activator of transcription (STAT)-mediated transcription in the absence of the ligand erythropoietin. The autoinhibitory activity of JAK2 is disrupted by the presence of the V617F mutation. Somatic mutation in JAK2 (V617F) gene has been reported in myeloid disorders. This study reports the prevalence of JAK2V617F using amplification refractory mutation system (ARMS)-polymerase chain reaction in 246 Egyptian patients with different myeloid disorders and studied the relationship between the JAK2V617F mutation and parameters in peripheral blood. The mutation was detected among 88 patients (35.8%) with different myeloid disorders. JAK2V617F was found among 81.4% of polycythemia vera (PV), 50% of essential thrombocythemia, 46.1% of primary myelofibrosis (PMF), 33.3% of philadelphia (Ph)-negative chronic myeloid leukemia, 33.3% of myelodysplastic syndrome (MDS)/myeloproliferative neoplasm (MPN), and 50% of refractory anemia with ringed sideroblasts associated with marked thrombocytosis (RARS-T) patients. Hemoglobin and white blood cells were significantly higher in the mutated group of MPN including PV, essential thrombocythemia, and PMF, whereas platelet counts were higher among the mutated PV, PMF, RARS-T, and MDS/MPN group. The identification of JAK2V617F mutations has raised the prospect of developing specific JAK2V617F inhibitors to treat mutated patients.
 ...
PMID:Acquired mutation of the tyrosine kinase JAK2V617F in Egyptian patients with myeloid disorders. 2103 66

Chronic myeloproliferative disorders share a stem cell-derived clonal myeloproliferation. This group of disorders include essential thrombocythemia (ET), polycythemia vera (PV), chronic myeloid leukemia, and primary myelofibrosis (PMF), with the respective features of thrombocytosis, erythrocytosis, and bone marrow fibrosis. These disorders can be associated with genetic mutations affecting protein tyrosine kinases, resulting in different configurations of abnormal signal transduction. The Janus tyrosine kinase 2 mutation can be used as a key diagnostic tool for diagnosing MPDs, specifically, ET, PV, and PMF. Patients with ET and PV are at an increased risk for thromboembolic and hemorrhagic events. We present a unique case of ET causing extensive arterial thromboembolism, despite being on adequate antithrombotic agents including warfarin and aspirin.
 ...
PMID:Medical Management of Extensive Arterial Thromboembolism in a Patient with Essential Thrombocythemia and Warfarin Failure. 2825 26