Expression data from patients with Essentiel Thrombocythemia (ET), Polycythemia Vera (PV), Primary Myelofibrosis (PMF) and control subjects
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ABSTRACT: We used microarrays to assess gene expression in patients with ET, PV, and PMF compared to control subjects Total RNA was purified from whole blood and amplified to biotin-labeled aRNA and hybridized to microarray chips.
Project description:Microarrays were used to assess gene expression in patients with ET, PV, and PMF before and after treatment with IFNalpha2 in a paired design.
Project description:To define the molecular abnormalities at the stem cell level in polycythemia vera (PV), we examined global gene expression in circulating CD34+ cells from 19 JAK2 V617F-positive PV patients and 6 normal individuals using Affymetrix oligonucleotide microarray technology. We observed that CD34+ cell gene expression not only differed between the PV patients and the normal controls but also between men and women PV patients. Based on these gender-specific differences in gene expression, we were able to identify 102 genes differentially regulated concordantly by both men and women, which likely represent a core set of genes whose dysregulation is involved in the pathogenesis of PV. Gene expression was verified by Q-PCR of patient CD34+ cell RNA. Using the 102 gene set and unsupervised hierarchical clustering, the 19 PV patients could be separated in two groups that differed significantly with respect to hemoglobin level, thrombosis frequency, splenomegaly, splenectomy or chemotherapy exposure, leukemic transformation and overall survival. These results were confirmed using top scoring pairs, which identified a different set of 29 genes that independently segregated the 19 patients into the same two clinical groups: those with an aggressive form of the disease (7 patients), and those with an indolent form (12 patients). Samples from 19 PV patients (8 men and 11 women) and 6 normal controls (3 men and 3 women) were analyzed using Affymetrix oligonucleotide microarray U133A.
Project description:To define the molecular abnormalities at the stem cell level in polycythemia vera (PV), we examined global gene expression in circulating CD34+ cells from 19 JAK2 V617F-positive PV patients and 6 normal individuals using Affymetrix oligonucleotide microarray technology. We observed that CD34+ cell gene expression not only differed between the PV patients and the normal controls but also between men and women PV patients. Based on these gender-specific differences in gene expression, we were able to identify 102 genes differentially regulated concordantly by both men and women, which likely represent a core set of genes whose dysregulation is involved in the pathogenesis of PV. Gene expression was verified by Q-PCR of patient CD34+ cell RNA. Using the 102 gene set and unsupervised hierarchical clustering, the 19 PV patients could be separated in two groups that differed significantly with respect to hemoglobin level, thrombosis frequency, splenomegaly, splenectomy or chemotherapy exposure, leukemic transformation and overall survival. These results were confirmed using top scoring pairs, which identified a different set of 29 genes that independently segregated the 19 patients into the same two clinical groups: those with an aggressive form of the disease (7 patients), and those with an indolent form (12 patients).
Project description:A global microRNA expression profile was obtained from gradient-purified granulocytes (>95% pure) collected at the time of screening and at cycle 4 of treatment Protocol #18424-256 is a Phase 2 study of the JAK1 and JAK2 inhibitor INCB01842 in patients with advanced polycythemia vera (PV) and essential thrombocythemia (ET) refractory to hydroxyurea; The aim was to to determine whether treatment with INC180424 was associated with changes in the global microRNA expression profile we compared granulocytes collected at baseline (screening) and at cycle 4
Project description:A global microRNA expression profile was obtained from gradient-purified granulocytes (>95% pure) collected at the time of screening and at cycle 4 of treatment Protocol #18424-256 is a Phase 2 study of the JAK1 and JAK2 inhibitor INCB01842 in patients with advanced polycythemia vera (PV) and essential thrombocythemia (ET) refractory to hydroxyurea;
Project description:BackgroundPegylated interferon alfa-2a (PEG-IFN-α-2a) is a potent immunomodulating agent capable of inducing high rate of hematologic and even complete molecular remission in patients with essential thrombocythemia (ET) and polycythemia vera (PV). We recently reported results of a phase 2 trial of PEG-IFN-α-2a in 83 patients with ET and PV after a median follow-up of 83 months. Here we report an analysis of bone marrow (BM) responses in these patients.MethodsAmong 83 patients, 58 (70%, PV 25, ET 31) had evaluable BM samples. BM responses and fibrosis grading were defined according to the International Working Group for Myeloproliferative Neoplasms Research and Treatment, and the European Consensus on grading of BM fibrosis, respectively. BM was assessed prior to enrollment, and every 6-24 months while on therapy in all patients, and after therapy discontinuation in some patients.ResultsThe median age of analyzed 58 patients was 52 years, and 29% were males. After a median follow-up of 84 months, 32 patients are still on study. Hematologic (HR) and molecular responses (MR) were seen in 93 and 69% patients, respectively. Twenty-nine patients (50%) had a BM response, including 13 (22%) with a complete BM response (BM-CR). Moreover, 13 patients (22%) have experienced complete resolution of bone marrow reticulin fibrosis. Patients with BM response had higher duration of HR and MR, and lower discontinuation rate. Furthermore, patients with BM-CR had a higher probability of complete MR. The median duration of BM-CR was 30 months, and 9 patients have maintained their BM-CR (69%), including five who have maintained their response after discontinuation of therapy. Despite this observation, the pattern of HR, MR and BM response, their durability and interrelation was heterogeneous.ConclusionsOur results show the ability of PEG-IFN-α-2a to induce complete BM responses in a subset of ET and PV patients, but its correlation with durable clinically relevant treatment benefit warrants further investigation. Trial registration This study is registered with ClinicalTrials.gov (NCT00452023), and is ongoing but not enrolling new patients.
Project description:This experiment was designed to identify genes differentially expressed in association with the JAK2V617F mutation in polycythemia vera (PV) and essential thrombocythemia (ET). Peripheral blood was obtained from 20 ET and 16 PV patients and erythroid progenitors were grown in semi-solid methylcellulose media supplemented with 0.01 U/ml erythropoietin. Individual clones were plucked and genotyped for the presence of the JAK2V617F mutation, and up to 20 normal and mutant colonies were pooled from each patient, and subjected to expression profiling. In total, 72 expression profiling datasets were generated, representing paired samples of normal and mutant cells from 36 patients.
Project description:Severe thrombocytopenia (platelets <50 × 109 /L) is associated with very poor outcome of patients with myelofibrosis (MF). As patients with primary myelofibrosis (PMF) differ from patients with postessential thrombocythemia (PET-MF) and postpolycythemia vera myelofibrosis (PPV-MF), we aimed to evaluate the significance of low platelets among these patients. We present clinical characteristics and outcome of patients with either PMF, PPV-MF, or PET-MF, and thrombocytopenia who presented to our institution between 1984 and 2015. Of 1269 patients (877 PMF, 212 PPV-MF, 180 PET-MF), 11% and 14% had platelets either <50 × 109 /L or between 50-100 × 109 /L, respectively. Patients with platelets <50 × 109 /L were most anemic and transfusion dependent, had highest blast count and unfavorable karyotype. In general, their overall and leukemia-free survival was the shortest with median time of 15 and 13 months, respectively; with incidence of acute leukemia almost twice as high as in the remaining patients (6.9 vs 3.6 cases per 100 person-years). Nevertheless, this observation remains mostly significant for patients with PMF, as those with PEV/PVT-MF have already significantly inferior prognosis with platelets <100 × 109 /L.