Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0032463 (polycythemia vera)
 3,374 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Essential thrombocythemia (ET) is traditionally considered to be a clonal disorder. No specific karyotypic abnormalities have been described, but the demonstration of clonality using X-chromosome inactivation patterns (XCIPs) has been used to differentiate ET from a non-clonal reactive thrombocytosis. However, these assays may be difficult to interpret, and contradictory results have been reported. We have studied 46 females with a diagnosis of ET according to the Polycythemia Vera Study Group (PVSG) criteria. XCIP results in 23 patients (50%) were uninterpretable due to either constitutive or possible acquired age-related skewing. Monoclonal myelopoiesis could be definitively shown in only 10 patients. Thirteen patients had polyclonal myelopoiesis, and in 8, it was possible to exclude clonal restriction to the megakaryocytic lineage. Furthermore, there was no evidence of clonal progenitors in purified CD34(+)CD33(-) and CD34(+)CD33(+) subpopulations from bone marrow of 2 of these 13 patients. There was no difference between patients with monoclonal and polyclonal myelopoiesis with respect to age or platelet count at diagnosis, duration of follow-up, incidence of hepatosplenomegaly, or hemorrhagic complications. However, polyclonal patients were less likely to have experienced thrombotic events (P =.039). These results suggest that ET is a heterogeneous disorder, and the clinical significance of clonality status warrants investigation in a larger study.
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PMID:A large proportion of patients with a diagnosis of essential thrombocythemia do not have a clonal disorder and may be at lower risk of thrombotic complications. 988 2

Tetrasomy 8 as a sole anomaly in hematological disorders is relatively rare. To the best of our knowledge, only 19 such cases have been described in the literature to date. Of them, acute myeloid leukemia (AML) in 13 (M1, one; M2, three; M4, one; M5, eight), acute lymphoblastic leukemia(ALL) in one, myelodysplastic syndrome(MDS) in 3, polycythemia vera(PV) and myelofibrosis(MF), one case each. Their median survival was 20 weeks. Here, we report the first case of a 29-year-old man with minimally differentiated AML (AML-M0) displaying a tetrasomy 8 clone. Immunophenotyping showed positivity with CD33, CD34 and intracellular MPO, but all lymphoid markers tested were negative. Conventional cytogenetics of bone marrow cells showed 84.9% of metaphases with tetrasomy 8 in addition to 15.1% with normal diploidy. However, Fluorescence in situ hybridization(FISH) using a centromeric probe specific for chromosome 8 revealed trisomy 8 in 14.2% of interphase nuclei besides tetrasomy 8 in 82.4%. The patient died four weeks after diagnosis without therapy. In conclusion, these findings suggest that tetrasomy 8 is associated with a heterogeneous group of myeloid disorders and heralds a bad prognosis. It may be a consequence of clonal evolution of trisomy 8.
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PMID:Isolated tetrasomy 8 in minimally differentiated acute myeloid leukemia (AML-M0). 1034 86

Acute erythroid leukemia in children is very rare. Here is a case of erythroleukemia in a child of age 1.5 years, which was diagnosed on peripheral smear, bone marrow examination, cytochemistry but was confirmed on immunophenotyping. CD45 versus side scatter demonstrated blast population (29%) expressing CD45 of variable intensity (dim to negative). The myeloid nature of blast population showed bright expression of cytoplasmic myeloperoxidase (MPO), heterogenous positivity of CD117 and dim expression of CD13, CD33. These blasts also showed bright positivity for CD71 which showed erythroid nature of blasts. Flow cytometry can be comprehensive enough to completely subtype cases of leukemias/myelodysplastic syndromes, polycythemia rubra vera, non-neoplastic conditions like reactive erythroid hyperplasia following immunosuppressive therapy or viral infections or nutritional deficiencies, unlyzed RBCs or thrombocytosis which may mimic acute erythroid leukemia on flow cytometry.
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PMID:Childhood acute erythroleukemia diagnosis by flow cytometry. 2139 10

Although BCR-ABL negative myeloproliferative neoplasms (MPN)--and especially myelofibrosis (MF)--are recognized to be associated with autoimmune phenomena, immune derangements in MPN have been much less studied. Myeloid-derived suppressor cells (MDSC) are one type of important immune modulator cell. Therefore, we studied MDSCs in MPN disease. MDSCs were studied in two cohorts: the first cohort was 55 patients including 16 primary myelofibrosis (PMF), 7 post-polycythemia vera (PV)-MF, 2 post-essential thrombocythemia (ET)-MF, 11 ET, 17 PV, 2 undefined MPN disorder, and 23 normal controls; the second cohort included 38 patients: 17 ET, 7 PMF, 3 ET-MF, 2 PV-MF, 9 PV patients, and 20 normal volunteers. The second cohort was studied using freshly collected specimens and a comparable age group as controls. CD11b(+), CD14(-), and CD33(+) cells were defined as MDSCs in both cohorts by flow cytometry. Since there are no differences in MDSC levels among different MPN categories, they were grouped as MPNs. The results showed that MDSCs were significantly elevated in MPNs compared with controls in both cohorts. We also performed RT-PCR and found that MPN patients have significantly elevated arginase-1 mRNA compared with controls, and sorted MDSCs were found to have suppressor T cell activity in MPNs, substantiating the hypothesis that levels of MDSCs are, in fact, deranged in MPNs. MDSC levels were not correlated with JAK2 status, white blood cells, Hb levels, platelet counts, splenomegaly, or the degree of bone marrow fibrosis (in MF). Further studies in immune therapy involving MDSC inhibitors or differentiation may be developed to treat MPN disease.
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PMID:Myeloid-derived suppressor cells in patients with myeloproliferative neoplasm. 2694 2