Project description:Patients with prefibrotic PMF have a heterogeneous risk for progression to myelofibrosis. This projects evaluates the potential of comprehensive DNA methylation profiling for predicting fibrotic progress.
Project description:Primary myelofibrosis (PMF) together with polycythemia vera (PV) and essential thrombocythemia (ET) belongs to the classic Philadelphia-negative myeloproliferative neoplasms (MPNs). PV and ET can evolve to secondary myelofibrosis (SMF) giving rise to post-PV (PPV) and post-ET (PET) myelofibrosis (MF). PMF and SMF patients are currently managed in the same way and prediction of survival is based on the same prognostic models, even if it has been demonstrated that they can’t accurately distinguish different risk categories in SMF. In the last few years interest grew concerning the ability of gene expression profiling (GEP) to provide valuable prognostic information for clinical decision making. To construct a molecular signature that can predict survival according to gene expression we studied GEP of granulocytes from 114 MF patients, including 35 prefibrotic/early PMF (Pre-PMF), 37 overt PMF (Overt-PMF), 26 PET and 16 PPV, using microarray platform.
Project description:Ph-negative myeloproliferative neoplasms (MPNs) are characterized by many somatic mutations which have already been shown useful in the prognostic assessment of MPN patients. Moreover, aberrant microRNA (miRNA) expression seems to add to the molecular complexity of MPNs, as specific miRNA signatures capable of discriminating MPN cells from those of normal donors were previously reported. In order to have a comprehensive picture of miRNA deregulation and its relationship with differential gene expression in primary myelofibrosis (PMF) cells, we obtained gene- (GEP) and miRNA expression profiles (miEP) of CD34+ cells from 31 healthy donors and 42 PMF patients using Affymetrix technology (HG-U219 and miRNA 2.0 arrays). Differentially expressed genes (DEG) and miRNAs (DEM) were sorted out by means of Partek Genomic Suite vs 6.6. Since each miRNA can target many mRNAs while a single mRNA can be targeted by multiple miRNAs, we performed Integrative Analysis (IA) by means of Ingenuity Pathway Analysis (IPA) to untangle this combinatorial complexity. In particular, IPA points out DEM-DEG pairs among experimentally validated interactions from TarBase, miRecords and Ingenuity Expert Findings as well as predicted microRNA-mRNA interactions from TargetScan. IPA microRNA Target Filter was then employed to select only the DEM-DEG pairs showing an anti-correlated expression pattern and to build regulatory networks. Finally, 3'UTR luciferase reporter assays were performed to validate IPA predicted miRNA-mRNA interactions. This study allowed the identification of different networks possibly involved in PMF onset and progression, highlighting an aberrant cross-regulation in miRNA-targets involved in malignant hematopoiesis. Furthermore, Integrative analysis was proved a powerful tool to unravel miRNA-mRNA interactions in functional networks, shedding light on the potential contribution of miRNAs to PMF pathogenesis. Gene expression profile (GEP) and miRNA expression profile (miEP) were performed starting from the same totalRNA of CD34+ cells from 42 PMF patients and 31 healthy donors (n=16 PB CD34+, n=15 BM CD34+) (1 replicate for each sample). In particular, GEP and miEP were performed on 23 PMF patients carrying the mutation JAK2V617F and 19 wild-type samples.
Project description:Primary myelofibrosis (PMF) is a clonal myeloproliferative neoplasm whose severity and treatment complexity is attributed to the presence of bone marrow (BM) fibrosis and alterations of stroma impairing the production of normal blood cells. Despite the recently discovered mutations including the JAK2V617F mutation in about half of patients, the primitive event responsible for the clonal proliferation is still unknown. In the highly inflammatory context of PMF, the presence of fibrosis associated with a neoangiogenesis and an osteosclerosis concomitant to the myeloproliferation and to the increase number of circulating hematopoietic progenitors suggests that the crosstalk between hematopoietic and stromal cells is deregulated in the PMF BM microenvironment. Within these niches, Mesenchymal Stromal Cells (BM-MSC) play a supportive role in the production of growth factors and extracellular matrix which regulate the proliferation, differentiation, adhesion and migration of hematopoietic progenitors. A transcriptome analysis of BM-MSC in PMF patients will help to characterize their molecular alterations and to understand their involvement in the hematopoietic progenitor deregulation that features PMF. Primary Myelofibrosis, mesenchymal stroma cells, bone marrow, myeloproliferative disorders Transcriptome analysis was performed on BM-MSC amplified in vitro after 3 to 5 passages. Agilent Whole Human Genome Oligo Microarrays were used to compare expression profiling of BM-MSC from PMF patients and healthy donors.
Project description:Primary myelofibrosis (PMF) is a clonal myeloproliferative neoplasm whose severity and treatment complexity is attributed to the presence of bone marrow (BM) fibrosis and alterations of stroma impairing the production of normal blood cells. Despite the recently discovered mutations including the JAK2V617F mutation in about half of patients, the primitive event responsible for the clonal proliferation is still unknown. In the highly inflammatory context of PMF, the presence of fibrosis associated with a neo-osteogenesis and an osteosclerosis concomitant to the myeloproliferation and to the increase number of circulating hematopoietic progenitors suggests that the crosstalk between hematopoietic cells and the osteoblastic niche is deregulated in the PMF BM microenvironment. Osteoblastic niche is well known to be an important support to regulate hematopoietic stem cell functions in bone marrow. A transcriptome analysis of bone marrow mesenchymal stem cells (BM-MSC) induced in vitro to differentiate in osteoblasts will help to understand the role of these cells in pathophysiology of PMF. Transcriptome analysis was performed on BM-MSC at J0 and J21 of in vitro osteoblastic differentiation. Agilent Whole Human Genome Oligo Microarrays were used to compare expression profiling of BM-MSCs from PMF patients and healthy donors before and after osteoblastic differentiation. Primary Myelofibrosis, mesenchymal stroma cells, bone marrow, myeloproliferative disorders
Project description:Primary myelofibrosis (PMF) is a clonal myeloproliferative neoplasm whose severity and treatment complexity is attributed to the presence of bone marrow (BM) fibrosis and alterations of stroma impairing the production of normal blood cells. Despite the recently discovered mutations including the JAK2V617F mutation in about half of patients, the primitive event responsible for the clonal proliferation is still unknown. In the highly inflammatory context of PMF, the presence of fibrosis associated with a neoangiogenesis and an osteosclerosis concomitant to the myeloproliferation and to the increase number of circulating hematopoietic progenitors suggests that the crosstalk between hematopoietic and stromal cells is deregulated in the PMF BM microenvironment. Within these niches, Mesenchymal Stromal Cells (BM-MSC) play a supportive role in the production of growth factors and extracellular matrix which regulate the proliferation, differentiation, adhesion and migration of hematopoietic progenitors. A transcriptome analysis of BM-MSC in PMF patients will help to characterize their molecular alterations and to understand their involvement in the hematopoietic progenitor deregulation that features PMF. Primary Myelofibrosis, mesenchymal stroma cells, bone marrow, myeloproliferative disorders
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:Ph-negative myeloproliferative neoplasms (MPNs) are characterized by many somatic mutations which have already been shown useful in the prognostic assessment of MPN patients. Moreover, aberrant microRNA (miRNA) expression seems to add to the molecular complexity of MPNs, as specific miRNA signatures capable of discriminating MPN cells from those of normal donors were previously reported. In order to have a comprehensive picture of miRNA deregulation and its relationship with differential gene expression in primary myelofibrosis (PMF) cells, we obtained gene- (GEP) and miRNA expression profiles (miEP) of CD34+ cells from 31 healthy donors and 42 PMF patients using Affymetrix technology (HG-U219 and miRNA 2.0 arrays). Differentially expressed genes (DEG) and miRNAs (DEM) were sorted out by means of Partek Genomic Suite vs 6.6. Since each miRNA can target many mRNAs while a single mRNA can be targeted by multiple miRNAs, we performed Integrative Analysis (IA) by means of Ingenuity Pathway Analysis (IPA) to untangle this combinatorial complexity. In particular, IPA points out DEM-DEG pairs among experimentally validated interactions from TarBase, miRecords and Ingenuity Expert Findings as well as predicted microRNA-mRNA interactions from TargetScan. IPA microRNA Target Filter was then employed to select only the DEM-DEG pairs showing an anti-correlated expression pattern and to build regulatory networks. Finally, 3'UTR luciferase reporter assays were performed to validate IPA predicted miRNA-mRNA interactions. This study allowed the identification of different networks possibly involved in PMF onset and progression, highlighting an aberrant cross-regulation in miRNA-targets involved in malignant hematopoiesis. Furthermore, Integrative analysis was proved a powerful tool to unravel miRNA-mRNA interactions in functional networks, shedding light on the potential contribution of miRNAs to PMF pathogenesis.