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Elisa BIANCHI
Professore Associato
Dipartimento di Scienze della Vita sede Centro di Medicina Rigenerativa
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Pubblicazioni
2023
- Chromosome 9p Duplication Promotes T-Cell Exhaustion and Enhances Stem Cell Clonogenic Potential in JAK2-Mutant Myeloproliferative Neoplasms
[Abstract in Rivista]
Norfo, Ruggiero; Carretta, Chiara; Parenti, Sandra; Badii, Filippo; Bertesi, Matteo; Rontauroli, Sebastiano; Tavernari, Lara; Genovese, Elena; Sperduti, Samantha; Enzo, Elena; Mirabile, Margherita; Pedrazzi, Francesca; Pessina, Chiara; Colugnat, Ilaria; Mora, Barbara; Maccaferri, Monica; Tenedini, Elena; Martinelli, Silvia; Bianchi, Elisa; Casarini, Livio; Potenza, Leonardo; Luppi, Mario; Tagliafico, Enrico; Guglielmelli, Paola; Simoni, Manuela; Passamonti, Francesco; Vannucchi, Alessandro Maria; Manfredini, Rossella
abstract
2023
- Comparison between Cultivated Oral Mucosa and Ocular Surface Epithelia for COMET Patients Follow-Up
[Articolo su rivista]
Attico, Eustachio; Galaverni, Giulia; Torello, Andrea; Bianchi, Elisa; Bonacorsi, Susanna; Losi, Lorena; Manfredini, Rossella; Lambiase, Alessandro; Rama, Paolo; Pellegrini, Graziella
abstract
Total bilateral Limbal Stem Cell Deficiency is a pathologic condition of the ocular surface due to the loss of corneal stem cells. Cultivated oral mucosa epithelial transplantation (COMET) is the only autologous successful treatment for this pathology in clinical application, although abnormal peripheric corneal vascularization often occurs. Properly characterizing the regenerated ocular surface is needed for a reliable follow-up. So far, the univocal identification of transplanted oral mucosa has been challenging. Previously proposed markers were shown to be co-expressed by different ocular surface epithelia in a homeostatic or perturbated environment. In this study, we compared the transcriptome profile of human oral mucosa, limbal and conjunctival cultured holoclones, identifying Paired Like Homeodomain 2 (PITX2) as a new marker that univocally distinguishes the transplanted oral tissue from the other epithelia. We validated PITX2 at RNA and protein levels to investigate 10-year follow-up corneal samples derived from a COMET-treated aniridic patient. Moreover, we found novel angiogenesis-related factors that were differentially expressed in the three epithelia and instrumental in explaining the neovascularization in COMET-treated patients. These results will support the follow-up analysis of patients transplanted with oral mucosa and provide new tools to understand the regeneration mechanism of transplanted corneas.
2023
- Inhibition of ERK1/2 signaling prevents bone marrow fibrosis by reducing osteopontin plasma levels in a myelofibrosis mouse model
[Articolo su rivista]
Bianchi, Elisa; Rontauroli, Sebastiano; Tavernari, Lara; Mirabile, Margherita; Pedrazzi, Francesca; Genovese, Elena; Sartini, Stefano; Dall'Ora, Massimiliano; Grisendi, Giulia; Fabbiani, Luca; Maccaferri, Monica; Carretta, Chiara; Parenti, Sandra; Fantini, Sebastian; Bartalucci, Niccolò; Calabresi, Laura; Balliu, Manjola; Guglielmelli, Paola; Potenza, Leonardo; Tagliafico, Enrico; Losi, Lorena; Dominici, Massimo; Luppi, Mario; Vannucchi, Alessandro Maria; Manfredini, Rossella
abstract
Clonal myeloproliferation and development of bone marrow (BM) fibrosis are the major pathogenetic events in myelofibrosis (MF). The identification of novel antifibrotic strategies is of utmost importance since the effectiveness of current therapies in reverting BM fibrosis is debated. We previously demonstrated that osteopontin (OPN) has a profibrotic role in MF by promoting mesenchymal stromal cells proliferation and collagen production. Moreover, increased plasma OPN correlated with higher BM fibrosis grade and inferior overall survival in MF patients. To understand whether OPN is a druggable target in MF, we assessed putative inhibitors of OPN expression in vitro and identified ERK1/2 as a major regulator of OPN production. Increased OPN plasma levels were associated with BM fibrosis development in the Romiplostim-induced MF mouse model. Moreover, ERK1/2 inhibition led to a remarkable reduction of OPN production and BM fibrosis in Romiplostim-treated mice. Strikingly, the antifibrotic effect of ERK1/2 inhibition can be mainly ascribed to the reduced OPN production since it could be recapitulated through the administration of anti-OPN neutralizing antibody. Our results demonstrate that OPN is a novel druggable target in MF and pave the way to antifibrotic therapies based on the inhibition of ERK1/2-driven OPN production or the neutralization of OPN activity.
2022
- SOX2 Is a Univocal Marker for Human Oral Mucosa Epithelium Useful in Post-COMET Patient Characterization
[Articolo su rivista]
Attico, Eustachio; Galaverni, Giulia; Bianchi, Elisa; Losi, Lorena; Manfredini, Rossella; Lambiase, Alessandro; Rama, Paolo; Pellegrini, Graziella
abstract
Total bilateral Limbal Stem Cells Deficiency is a pathologic condition of the ocular surface due to loss or impairment of corneal stem cell function, altering homeostasis of the corneal epithelium. Cultivated Oral Mucosa Epithelial Transplantation (COMET) is the only autologous treatment for this pathology. During the follow-up, a proper characterization of the transplanted oral mucosa on the ocular surface supports understanding the regenerative process. The previously proposed markers for oral mucosa identification (e.g., keratins 3 and 13) are co-expressed by corneal and conjunctival epithelia. Here, we propose a new specific marker to distinguish human oral mucosa from the epithelia of the ocular surface. We compared the transcriptome of holoclones (stem cells) from the human oral mucosa, limbal and conjunctival cultures by microarray assay. High expression of SOX2 identified the oral mucosa vs. cornea and conjunctiva, while PAX6 was highly expressed in corneal and conjunctival epithelia. The transcripts were validated by qPCR, and immunological methods identified the related proteins. Finally, the proposed markers were used to analyze a 10-year follow-up aniridic patient treated by COMET. These findings will support the follow-up analysis of COMET treated patients and help to shed light on the mechanism of corneal repair and regeneration.
2022
- The Response to Oxidative Damage Correlates with Driver Mutations and Clinical Outcome in Patients with Myelofibrosis
[Articolo su rivista]
Genovese, E.; Mirabile, M.; Rontauroli, S.; Sartini, S.; Fantini, S.; Tavernari, L.; Maccaferri, M.; Guglielmelli, P.; Bianchi, E.; Parenti, S.; Carretta, C.; Mallia, S.; Castellano, S.; Colasante, C.; Balliu, M.; Bartalucci, N.; Palmieri, R.; Ottone, T.; Mora, B.; Potenza, L.; Passamonti, F.; Voso, M. T.; Luppi, M.; Vannucchi, A. M.; Tagliafico, E.; Manfredini, R.
abstract
Myelofibrosis (MF) is the Philadelphia-negative myeloproliferative neoplasm characterized by the worst prognosis and no response to conventional therapy. Driver mutations in JAK2 and CALR impact on JAK-STAT pathway activation but also on the production of reactive oxygen species (ROS). ROS play a pivotal role in inflammation-induced oxidative damage to cellular components including DNA, therefore leading to greater genomic instability and promoting cell transformation. In order to unveil the role of driver mutations in oxidative stress, we assessed ROS levels in CD34+ hematopoietic stem/progenitor cells of MF patients. Our results demonstrated that ROS production in CD34+ cells from CALR-mutated MF patients is far greater compared with patients harboring JAK2 mutation, and this leads to increased oxidative DNA damage. Moreover, CALR-mutant cells show less superoxide dismutase (SOD) antioxidant activity than JAK2-mutated ones. Here, we show that high plasma levels of total antioxidant capacity (TAC) correlate with detrimental clinical features, such as high levels of lactate dehydrogenase (LDH) and circulating CD34+ cells. Moreover, in JAK2-mutated patients, high plasma level of TAC is also associated with a poor overall survival (OS), and multivariate analysis demonstrated that high TAC classification is an independent prognostic factor allowing the identification of patients with inferior OS in both DIPSS lowest and highest categories. Altogether, our data suggest that a different capability to respond to oxidative stress can be one of the mechanisms underlying disease progression of myelofibrosis.
2021
- Gene expression profile correlates with molecular and clinical features in patients with myelofibrosis
[Articolo su rivista]
Rontauroli, S.; Castellano, S.; Guglielmelli, P.; Zini, R.; Bianchi, E.; Genovese, E.; Carretta, C.; Parenti, S.; Fantini, S.; Mallia, S.; Tavernari, L.; Sartini, S.; Mirabile, M.; Mannarelli, C.; Gesullo, F.; Pacilli, A.; Pietra, D.; Rumi, E.; Salmoiraghi, S.; Mora, B.; Villani, L.; Grilli, A.; Rosti, V.; Barosi, G.; Passamonti, F.; Rambaldi, A.; Malcovati, L.; Cazzola, M.; Bicciato, S.; Tagliafico, E.; Vannucchi, A. M.; Manfredini, R.
abstract
Myelofibrosis (MF) belongs to the family of classic Philadelphia-negative myeloproliferative neoplasms (MPNs). It can be primary myelofibrosis (PMF) or secondary myelofibrosis (SMF) evolving from polycythemia vera (PV) or essential thrombocythemia (ET). Despite the differences, PMF and SMF patients are currently managed in the same way, and prediction of survival is based on the same clinical and genetic features. In the last few years, interest has grown concerning the ability of gene expression profiles (GEPs) to provide valuable prognostic information. Here, we studied the GEPs of granulocytes from 114 patients with MF, using a microarray platform to identify correlations with patient characteristics and outcomes. Cox regression analysis led to the identification of 201 survival-related transcripts characterizing patients who are at high risk for death. High-risk patients identified by this gene signature displayed an inferior overall survival and leukemia-free survival, together with clinical and molecular detrimental features included in contemporary prognostic models, such as the presence of high molecular risk mutations. The high-risk group was enriched in post-PV and post-ET MF and JAK2V617F homozygous patients, whereas pre-PMF was more frequent in the low-risk group. These results demonstrate that GEPs in MF patients correlate with their molecular and clinical features, particularly their survival, and represent the proof of concept that GEPs might provide complementary prognostic information to be applied in clinical decision making.
2021
- Increased Plasma Levels of lncRNAs LINC01268, GAS5 and MALAT1 Correlate with Negative Prognostic Factors in Myelofibrosis
[Articolo su rivista]
Fantini, Sebastian; Rontauroli, Sebastiano; Sartini, Stefano; Mirabile, Margherita; Bianchi, Elisa; Badii, Filippo; Maccaferri, Monica; Guglielmelli, Paola; Ottone, Tiziana; Palmieri, Raffaele; Genovese, Elena; Carretta, Chiara; Parenti, Sandra; Mallia, Selene; Tavernari, Lara; Salvadori, Costanza; Gesullo, Francesca; Maccari, Chiara; Zizza, Michela; Grande, Alexis; Salmoiraghi, Silvia; Mora, Barbara; Potenza, Leonardo; Rosti, Vittorio; Passamonti, Francesco; Rambaldi, Alessandro; Voso, Maria Teresa; Mecucci, Cristina; Tagliafico, Enrico; Luppi, Mario; Vannucchi, Alessandro Maria; Manfredini, Rossella
abstract
: Long non-coding RNAs (lncRNAs) have been recently described as key mediators in the development of hematological malignancies. In the last years, circulating lncRNAs have been proposed as a new class of non-invasive biomarkers for cancer diagnosis and prognosis and to predict treatment response. The present study is aimed to investigate the potential of circulating lncRNAs as non-invasive prognostic biomarkers in myelofibrosis (MF), the most severe among Philadelphia-negative myeloproliferative neoplasms. We detected increased levels of seven circulating lncRNAs in plasma samples of MF patients (n = 143), compared to healthy controls (n = 65). Among these, high levels of LINC01268, MALAT1 or GAS5 correlate with detrimental clinical variables, such as high count of leukocytes and CD34+ cells, severe grade of bone marrow fibrosis and presence of splenomegaly. Strikingly, high plasma levels of LINC01268 (p = 0.0018), GAS5 (p = 0.0008) or MALAT1 (p = 0.0348) are also associated with a poor overall-survival while high levels of LINC01268 correlate with a shorter leukemia-free-survival. Finally, multivariate analysis demonstrated that the plasma level of LINC01268 is an independent prognostic variable, suggesting that, if confirmed in future in an independent patients' cohort, it could be used for further studies to design an updated classification model for MF patients.
2021
- Mutated clones driving leukemic transformation are already detectable at the single-cell level in CD34-positive cells in the chronic phase of primary myelofibrosis
[Articolo su rivista]
Parenti, Sandra; Rontauroli, Sebastiano; Carretta, Chiara; Mallia, Selene; Genovese, Elena; Chiereghin, Chiara; Peano, Clelia; Tavernari, Lara; Bianchi, Elisa; Fantini, Sebastian; Sartini, Stefano; Romano, Oriana; Bicciato, Silvio; Tagliafico, Enrico; Della Porta, Matteo; Manfredini, Rossella
abstract
Disease progression of myeloproliferative neoplasms is the result of increased genomic complexity. Since the ability to predict disease evolution is crucial for clinical decisions, we studied single-cell genomics and transcriptomics of CD34-positive cells from a primary myelofibrosis (PMF) patient who progressed to acute myeloid leukemia (AML) while receiving Ruxolitinib. Single-cell genomics allowed the reconstruction of clonal hierarchy and demonstrated that TET2 was the first mutated gene while FLT3 was the last one. Disease evolution was accompanied by increased clonal heterogeneity and mutational rate, but clones carrying TP53 and FLT3 mutations were already present in the chronic phase. Single-cell transcriptomics unraveled repression of interferon signaling suggesting an immunosuppressive effect exerted by Ruxolitinib. Moreover, AML transformation was associated with a differentiative block and immune escape. These results suggest that single-cell analysis can unmask tumor heterogeneity and provide meaningful insights about PMF progression that might guide personalized therapy.
2020
- Genomic analysis of hematopoietic stem cell at the single-cell level: Optimization of cell fixation and whole genome amplification (WGA) protocol
[Articolo su rivista]
Carretta, C.; Mallia, S.; Genovese, E.; Parenti, S.; Rontauroli, S.; Bianchi, E.; Fantini, S.; Sartini, S.; Tavernari, L.; Tagliafico, E.; Manfredini, R.
abstract
Single-cell genomics has become the method of choice for the study of heterogeneous cell populations and represents an elective application in defining the architecture and clonal evolution in hematological neoplasms. Reconstructing the clonal evolution of a neoplastic population therefore represents the main way to understand more deeply the pathogenesis of the neoplasm, but it is also a potential tool to understand the evolution of the tumor population with respect to its response to therapy. Pre-analytical phase for single-cell genomics analysis is crucial to obtain a cell population suitable for single-cell sorting, and whole genome amplification is required to obtain the necessary amount of DNA from a single cell in order to proceed with sequencing. Here, we evaluated the impact of different methods of cellular immunostaining, fixation and whole genome amplification on the efficiency and yield of single-cell sequencing.
2020
- Preclinical study for treatment of hypospadias by advanced therapy medicinal products
[Articolo su rivista]
Sceberras, V.; Attico, E.; Bianchi, E.; Galaverni, G.; Melonari, M.; Corradini, F.; Fantacci, M.; Ribbene, A.; Losi, L.; Balò, S.; Lazzeri, M.; Trombetta, C.; Rizzo, M.; Manfredini, R.; Barbagli, G.; Pellegrini, G.
abstract
Purpose
This paper explores the feasibility of a new therapy for the treatment of hypospadias patients. Hypospadias is a very common congenital malformation of male genitals, with very high rate of recurrences after surgery. The field of regenerative medicine, which offers innovative solutions for many pathologies, still does not offer reliable solution for this pathology. Here, we propose quality, safety, and clinical feasibility assessment for an oral mucosa advanced therapy medicinal product (ATMP) grown on a biocompatible scaffold for a clinical study on urethral reconstruction of hypospadias patients.
Methods
Urethral and oral mucosal epithelia from donor biopsies were cultivated between two fibrin layers, under clinical-grade conditions for cell and tissue characterization and comparison, aimed at tissue engineering. In addition, single-clone analyses were performed to analyze gene expression profiles of the two epithelia by microarray technology.
Results
Oral mucosa appeared suitable for urethral reconstruction. The resulting ATMP was proven to maintain stem cells and regenerative potency. The preclinical safety studies were performed on human tissues to assess abnormalities and tumorigenicity, and confirmed the safety of the ATMP. Finally, the patient selection and the clinical protocol for the upcoming clinical trial were defined.
Conclusions
Against this backdrop, in this paper, we are proposing a new reproducible and reliable ATMP for the treatment of hypospadias.
2019
- Calreticulin Ins5 and Del52 mutations impair unfolded protein and oxidative stress responses in K562 cells expressing CALR mutants
[Articolo su rivista]
Salati, Simona; Genovese, Elena; Carretta, Chiara; Zini, Roberta; Bartalucci, Niccolò; Prudente, Zelia; Pennucci, Valentina; Ruberti, Samantha; Rossi, Chiara; Rontauroli, Sebastiano; Enzo, Elena; Calabresi, Laura; Balliu, Manjola; Mannarelli, Carmela; Bianchi, Elisa; Guglielmelli, Paola; Tagliafico, Enrico; Vannucchi, Alessandro M; Manfredini, Rossella
abstract
Somatic mutations of calreticulin (CALR) have been described in approximately 60-80% of JAK2 and MPL unmutated Essential Thrombocythemia and Primary Myelofibrosis patients. CALR is an endoplasmic reticulum (ER) chaperone responsible for proper protein folding and calcium retention. Recent data demonstrated that the TPO receptor (MPL) is essential for the development of CALR mutant-driven Myeloproliferative Neoplasms (MPNs). However, the precise mechanism of action of CALR mutants haven't been fully unraveled. In this study, we showed that CALR mutants impair the ability to respond to the ER stress and reduce the activation of the pro-apoptotic pathway of the unfolded protein response (UPR). Moreover, our data demonstrated that CALR mutations induce increased sensitivity to oxidative stress, leading to increase oxidative DNA damage. We finally demonstrated that the downmodulation of OXR1 in CALR-mutated cells could be one of the molecular mechanisms responsible for the increased sensitivity to oxidative stress mediated by mutant CALR. Altogether, our data identify novel mechanisms collaborating with MPL activation in CALR-mediated cellular transformation. CALR mutants negatively impact on the capability of cells to respond to oxidative stress leading to genomic instability and on the ability to react to ER stress, causing resistance to UPR-induced apoptosis.
2018
- Calreticulin affects hematopoietic stem/progenitor cell fate by impacting erythroid and megakaryocytic differentiation
[Articolo su rivista]
Salati, Simona; Prudente, Zelia; Genovese, Elena; Pennucci, Valentina; Rontauroli, Sebastiano; Bartalucci, Niccolo'; Mannarelli, Carmela; Ruberti, Samantha; Zini, Roberta; Rossi, Chiara; Bianchi, Elisa; Guglielmelli, Paola; Tagliafico, Enrico; Vannucchi, Alessandro M; Manfredini, Rossella
abstract
Calreticulin (CALR) is a chaperone protein that localizes primarily to the endoplasmic reticulum (ER) lumen where it is responsible for the control of proper folding of neo-synthesized glycoproteins and for the retention of calcium. Recently, mutations affecting exon 9 of the CALR gene have been described in approximately 40% of patients with myeloproliferative neoplasms (MPNs). Although the role of mutated CALR in the development of MPNs has begun to be clarified, there are still no data available on the function of wild-type (WT) CALR during physiological hematopoiesis. In order to shed light on the role of WT CALR during normal hematopoiesis, we performed gene silencing and overexpression experiments in Hematopoietic Stem Progenitor Cells (HSPCs). Our results showed that CALR overexpression is able to affect physiological hematopoiesis by enhancing both erythroid and megakaryocytic (MK) differentiation. In agreement with overexpression data, CALR silencing caused a significant decrease in both erythroid and MK differentiation of human HSPCs. Gene expression profiling (GEP) analysis showed that CALR is able to affect the expression of several genes involved in HSPCs differentiation towards both the erythroid and MK lineages. Moreover, GEP data also highlighted the modulation of several genes involved in ER stress response, unfolded protein response (UPR), DNA repair and of several genes already described to play a role in MPN development, such as pro-inflammatory cytokines and hematological neoplasms-related markers. Altogether, our data unraveled a new and unexpected role for CALR in the regulation of normal hematopoietic differentiation. Moreover, by showing the impact of CALR on the expression of genes involved in several biological processes already described in cellular transformation, our data strongly suggest a more complex role for CALR in MPN development that goes beyond the activation of the THPO receptor and involves ER stress response, UPR and DNA repair.
2018
- Involvement of MAF/SPP1 axis in the development of bone marrow fibrosis in PMF patients
[Articolo su rivista]
Ruberti, S; Bianchi, E; Guglielmelli, P; Rontauroli, S; Barbieri, G; Tavernari, L; Fanelli, T; Norfo, R; Pennucci, V; Fattori, G. Corbizi; Mannarelli, C; Bartalucci, N; Mora, B; Elli, L; Avanzini, M. A; Rossi, C; Salmoiraghi, S; Zini, R; Salati, S; Prudente, Z; Rosti, V; Passamonti, F; Rambaldi, A; Ferrari, S; Tagliafico, E; Vannucchi, A. M; Manfredini, R.
abstract
Primary myelofibrosis (PMF) is a myeloproliferative neoplasm characterized by hyperplastic megakaryopoiesis and myelofibrosis. We recently described the upregulation of MAF (v-maf avian musculoaponeurotic fibrosarcoma oncogene homolog) in PMF CD34+ hematopoietic progenitor cells (HPCs) compared to healthy donor. Here we demonstrated that MAF is also upregulated in PMF compared with the essential thrombocytemia (ET) and polycytemia vera (PV) HPCs. MAF overexpression and knockdown experiments shed some light into the role of MAF in PMF pathogenesis, by demonstrating that MAF favors the megakaryocyte and monocyte/macrophage commitment of HPCs and leads to the increased expression of proinflammatory and profibrotic mediators. Among them, we focused our further studies on SPP1 and LGALS3. We assessed SPP1 and LGALS3 protein levels in 115 PMF, 47 ET and 24 PV patients plasma samples and we found that SPP1 plasma levels are significantly higher in PMF compared with ET and PV patients. Furthermore, in vitro assays demonstrated that SPP1 promotes fibroblasts and mesenchymal stromal cells proliferation and collagen production. Strikingly, clinical correlation analyses uncovered that higher SPP1 plasma levels in PMF patients correlate with a more severe fibrosis degree and a shorter overall survival. Collectively our data unveil that MAF overexpression contributes to PMF pathogenesis by driving the deranged production of the profibrotic mediator SPP1.
2018
- Role of TGF-β1/miR-382-5p/SOD2 axis in the induction of oxidative stress in CD34+ cells from primary myelofibrosis
[Articolo su rivista]
Rossi, Chiara; Zini, Roberta; Rontauroli, Sebastiano; Ruberti, Samantha; Prudente, Zelia; Barbieri, Greta; Bianchi, Elisa; Salati, Simona; Genovese, Elena; Bartalucci, Niccolò; Guglielmelli, Paola; Tagliafico, Enrico; Rosti, Vittorio; Barosi, Giovanni; Vannucchi, Alessandro M.; Manfredini, Rossella
abstract
Primary myelofibrosis (PMF) is a myeloproliferative neoplasm characterized by an excessive production of pro-inflammatory cytokines resulting in chronic inflammation and genomic instability. Besides the driver mutations in JAK2, MPL, and CALR genes, the deregulation of miRNA expression may also contribute to the pathogenesis of PMF. To this end, we recently reported the upregulation of miR-382-5p in PMF CD34+ cells. In order to unveil the mechanistic details of the role of miR-382-5p in pathogenesis of PMF, we performed gene expression profiling of CD34+ cells overexpressing miR-382-5p. Among the downregulated genes, we identified superoxide dismutase 2 (SOD2), which is a predicted target of miR-382-5p. Subsequently, we confirmed miR-382-5p/SOD2 interaction by luciferase assay and we showed that miR-382-5p overexpression in CD34+ cells causes the decrease in SOD2 activity leading to reactive oxygen species (ROS) accumulation and oxidative DNA damage. In addition, our data indicate that inhibition of miR-382-5p in PMF CD34+ cells restores SOD2 function, induces ROS disposal, and reduces DNA oxidation. Since the pro-inflammatory cytokine transforming growth factor-β1 (TGF-β1) is a key player in PMF pathogenesis, we further investigated the effect of TGF-β1 on ROS and miR-382-5p levels. Our data showed that TGF-β1 treatment enhances miR-382-5p expression and reduces SOD2 activity leading to ROS accumulation. Finally, inhibition of TGF-β1 signaling in PMF CD34+ cells by galunisertib significantly reduced miR-382-5p expression and ROS accumulation and restored SOD2 activity. As a whole, this study reports that TGF-β1/miR-382-5p/SOD2 axis deregulation in PMF cells is linked to ROS overproduction that may contribute to enhanced oxidative stress and inflammation. Our results suggest that galunisertib may represent an effective drug reducing abnormal oxidative stress induced by TGF-β1 in PMF patients. Database linking: GEO: https://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE103464.
2017
- CALR mutational status identifies different disease subtypes of essential thrombocythemia showing distinct expression profiles
[Articolo su rivista]
Zini, Roberta; Guglielmelli, Paola; Pietra, Daniela; Rumi, Elisa; Rossi, Chiara; Rontauroli, Sebastiano; Genovese, Elena; Fanelli, Tiziana; Calabresi, Laura; Bianchi, Elisa; Salati, Simona; Cazzola, Mario; Tagliafico, Enrico; Vannucchi, Alessandro M.; Manfredini, Rossella
abstract
Polycythemia vera (PV) and essential thrombocythemia (ET) are Philadelphia-negative myeloproliferative neoplasms (MPNs) characterized by erythrocytosis and thrombocytosis, respectively. Approximately 95% of PV and 50-70% of ET patients harbor the V617F mutation in the exon 14 of JAK2 gene, while about 20-30% of ET patients carry CALRins5 or CALRdel52 mutations. These ET CALR-mutated subjects show higher platelet count and lower thrombotic risk compared to JAK2-mutated patients. Here, we showed that CALR-mutated and JAK2V617F-positive CD34+ cells display different gene and miRNA expression profiles. Indeed, we highlighted several pathways differentially activated between JAK2V617F- and CALR-mutated progenitors, i.e., mTOR, MAPK/PI3K, and MYC pathways. Furthermore, we unveiled that the expression of several genes involved in DNA repair, chromatin remodeling, splicing, and chromatid cohesion are decreased in CALR-mutated cells. According to the low risk of thrombosis in CALR-mutated patients, we also found the downregulation of several genes involved in thrombin signaling and platelet activation. As a whole, these data support the model that CALR-mutated ET could be considered as a distinct disease entity from JAK2V617F-positive MPNs and may provide the molecular basis supporting the different clinical features of these patients.
2017
- Deregulated expression of miR-29a-3p, miR-494-3p and miR-660-5p affects sensitivity to tyrosine kinase inhibitors in CML leukemic stem cells
[Articolo su rivista]
Salati, Simona; Salvestrini, Valentina; Carretta, Chiara; Genovese, Elena; Rontauroli, Sebastiano; Zini, Roberta; Rossi, Chiara; Ruberti, Samantha; Bianchi, Elisa; Barbieri, Greta; Curti, Antonio; Castagnetti, Fausto; Gugliotta, Gabriele; Rosti, Gianantonio; Bergamaschi, Micaela; Tafuri, Agostino; Tagliafico, Enrico; Lemoli, Roberto; Manfredini, Rossella
abstract
The development of Imatinib mesylate (IM), which targets the oncogenic BCRABL fusion protein, has greatly improved the outcome of Chronic Myeloid Leukemia (CML) patients. However, BCR-ABL-positive progenitors can be detected in CML patients in complete cytogenetic response. Several evidence suggests that CML stem cells are intrinsically resistant to Tyrosine Kinase Inhibitors (TKI), and therefore they represent the most likely candidate responsible for disease relapse. In this work, we investigated the microRNA (miRNA) expression profile of different subpopulations of CML Leukemic Stem Cells (LSCs): Lin-CD34+CD38-and Lin-CD34-CD38-cells. These cell fractions have been previously shown to be endowed with TKI intrinsic resistance. Our analysis identified 33 common deregulated miRNAs in CML LSCs. Among those, 8 miRNAs were deregulated in CML independently from BCR-ABL kinase activity and therefore are likely to be involved in the BCR-ABL-independent resistance to TKI that characterizes CML LSCs. In particular, the up-regulation of miR-29a-3p and miR-660-5p observed in CML LSCs, led to the down-regulation of their respective targets TET2 and EPAS1 and conferred TKI-resistance to CML LSCs in vitro. On the other hand, miR-494-3p down-regulation in CML LSCs, leading to c-MYC up-regulation, was able to decrease TKI-induced apoptosis. These results demonstrate that aberrant miRNA expression in CML LSCs could contribute to the intrinsic TKIresistance observed in these cell populations, and support the development of novel therapies aimed at targeting aberrantly regulated miRNAs or their targets in order to effectively eradicate CML LSCs.
2017
- miR-494-3p overexpression promotes megakaryocytopoiesis in primary myelofibrosis hematopoietic stem/progenitor cells by targeting SOCS6
[Articolo su rivista]
Rontauroli, Sebastiano; Norfo, Ruggiero; Pennucci, Valentina; Zini, Roberta; Ruberti, Samantha; Bianchi, Elisa; Salati, Simona; Prudente, Zelia; Rossi, Chiara; Rosti, Vittorio; Guglielmelli, Paola; Barosi, Giovanni; Vannucchi, Alessandro; Tagliafico, Enrico; Manfredini, Rossella
abstract
Primary myelofibrosis (PMF) is a chronic Philadelphia-negative myeloproliferative neoplasm characterized by hematopoietic stem cell-derived clonal myeloproliferation, involving especially the megakaryocyte lineage. To better characterize how the altered expression of microRNAs might contribute to PMF pathogenesis, we have previously performed the integrative analysis of gene and microRNA expression profiles of PMF hematopoietic stem/progenitor cells (HSPCs), which allowed us to identify miR- 494-3p as the upregulated microRNA predicted to target the highest number of downregulated mRNAs. To elucidate the role of miR-494-3p in hematopoietic differentiation, in the present study we demonstrated that miR-494-3p enforced expression in normal HSPCs promotes megakaryocytopoiesis. Gene expression profiling upon miR-494-3p overexpression allowed the identification of genes commonly downregulated both after microRNA overexpression and in PMF CD34+ cells. Among them, suppressor of cytokine signaling 6 (SOCS6) was confirmed to be a miR-494-3p target by luciferase assay. Western blot analysis showed reduced level of SOCS6 protein as well as STAT3 activation in miR-494-3p overexpressing cells. Furthermore, transient inhibition of SOCS6 expression in HSPCs demonstrated that SOCS6 silencing stimulates megakaryocytopoiesis, mimicking the phenotypic effects observed upon miR-494-3p overexpression. Finally, to disclose the contribution of miR-494-3p upregulation to PMF pathogenesis, we performed inhibition experiments in PMF HSPCs, which showed that miR-494-3p silencing led to SOCS6 upregulation and impaired megakaryocyte differentiation. Taken together, our results describe for the first time the role of miR-494- 3p during normal HSPC differentiation and suggest that its increased expression, and the subsequent downregulation of its target SOCS6, might contribute to the megakaryocyte hyperplasia commonly observed in PMF patients.
2017
- Molecular and functional characterization of CD133+ stem/progenitor cells infused in patients with end-stage liver disease reveals their interplay with stromal liver cells
[Articolo su rivista]
Catani, Lucia; Sollazzo, Daria; Bianchi, Elisa; Ciciarello, Marilena; Antoniani, Chiara; Foscoli, Licia; Caraceni, Paolo; Giannone, Ferdinando Antonino; Baldassarre, Maurizio; Giordano, Rosaria; Montemurro, Tiziana; Montelatici, Elisa; D'Errico, Antonia; Andreone, Pietro; Giudice, Valeria; Curti, Antonio; Manfredini, Rossella; Lemoli, Roberto Massimo
abstract
Background aims Growing evidence supports the therapeutic potential of bone marrow (BM)-derived stem/progenitor cells for end-stage liver disease (ESLD). We recently demonstrated that CD133+ stem/progenitor cell (SPC) reinfusion in patients with ESLD is feasible and safe and improve, albeit transiently, liver function. However, the mechanism(s) through which BM-derived SPCs may improve liver function are not fully elucidated. Methods Here, we characterized the circulating SPCs compartment of patients with ESLD undergoing CD133+ cell therapy. Next, we set up an in vitro model mimicking SPCs/liver microenvironment interaction by culturing granulocyte colony-stimulating factor (G-CSF)-mobilized CD133+and LX-2 hepatic stellate cells. Results We found that patients with ESLD show normal basal levels of circulating hematopoietic and endothelial progenitors with impaired clonogenic ability. After G-CSF treatment, patients with ESLD were capable to mobilize significant numbers of functional multipotent SPCs, and interestingly, this was associated with increased levels of selected cytokines potentially facilitating SPC function. Co-culture experiments showed, at the molecular and functional levels, the bi-directional cross-talk between CD133+ SPCs and human hepatic stellate cells LX-2. Human hepatic stellate cells LX-2 showed reduced activation and fibrotic potential. In turn, hepatic stellate cells enhanced the proliferation and survival of CD133+ SPCs as well as their endothelial and hematopoietic function while promoting an anti-inflammatory profile. Discussion We demonstrated that the interaction between CD133+ SPCs from patients with ESLD and hepatic stellate cells induces significant functional changes in both cellular types that may be instrumental for the improvement of liver function in cirrhotic patients undergoing cell therapy.
2017
- Role of miR-34a-5p in Hematopoietic Progenitor Cells Proliferation and Fate Decision: Novel Insights into the Pathogenesis of Primary Myelofibrosis
[Articolo su rivista]
Bianchi, Elisa; Ruberti, Samantha; Rontauroli, Sebastiano; Guglielmelli, Paola; Salati, Simona; Rossi, Chiara; Zini, Roberta; Tagliafico, Enrico; Vannucchi, Alessandro Maria; Manfredini, Rossella
abstract
Primary Myelofibrosis (PMF) is a chronic Philadelphia-negative myeloproliferative neoplasm characterized by a skewed megakaryopoiesis and an overproduction of proinflammatory and profibrotic mediators that lead to the development of bone marrow (BM) fibrosis. Since we recently uncovered the upregulation of miR-34a-5p in PMF CD34+ hematopoietic progenitor cells (HPCs), in order to elucidate its role in PMF pathogenesis here we unravelled the effects of miR-34a-5p overexpression in HPCs. We showed that enforced expression of miR-34a-5p partially constrains proliferation and favours the megakaryocyte and monocyte/macrophage commitment of HPCs. Interestingly, we identified lymphoid enhancer-binding factor 1 (LEF1) and nuclear receptor subfamily 4, group A, member 2 (NR4A2) transcripts as miR-34a-5p-targets downregulated after miR-34a-5p overexpression in HPCs as well as in PMF CD34+ cells. Remarkably, the knockdown of NR4A2 in HPCs mimicked the antiproliferative effects of miR-34a-5p overexpression, while the silencing of LEF1 phenocopied the effects of miR-34a-5p overexpression on HPCs lineage choice, by favouring the megakaryocyte and monocyte/macrophage commitment. Collectively our data unravel the role of miR-34a-5p in HPCs fate decision and suggest that the increased expression of miR-34a-5p in PMF HPCs could be important for the skewing of megakaryopoiesis and the production of monocytes, that are key players in BM fibrosis in PMF patients.
2016
- Genomic landscape of megakaryopoiesis and platelet function defects
[Articolo su rivista]
Bianchi, Elisa; Norfo, Ruggiero; Pennucci, Valentina; Zini, Roberta; Manfredini, Rossella
abstract
Megakaryopoiesis is a complex, stepwise process that takes place largely in the bone marrow. At the apex of the hierarchy, hematopoietic stem cells undergo a number of lineage commitment decisions that ultimately lead to the production of polyploid megakaryocytes. On average, megakaryocytes release 1011 platelets per day into the blood that repair vascular injuries and prevent excessive bleeding. This differentiation process is tightly controlled by exogenous and endogenous factors, which have been the topics of intense research in the hematopoietic field. Indeed, a skewing of megakaryocyte commitment and differentiation may entail the onset of myeloproliferative neoplasms and other preleukemic disorders together with acute megakaryoblastic leukemia, whereas quantitative or qualitative defects in platelet production can lead to inherited platelet disorders. The recent advent of next-generation sequencing has prompted mapping of the genomic landscape of these conditions to provide an accurateview of the underlying lesions. The aims of this review are to introduce the physiological pathways of megakaryopoiesis and to present landmark studies on acquired and inherited disorders that target them. These studies have not only introduced a new era in the fields of molecular medicine and targeted therapies but may also provide us with a better understanding ofthemechanismsunderlying normalmegakaryopoiesis and thrombopoiesis that can informeffortsto create alternativesources of megakaryocytes and platelets.
2016
- Integrative analysis of copy number and gene expression data suggests novel pathogenetic mechanisms in primary myelofibrosis
[Articolo su rivista]
Salati, Simona; Zini, Roberta; Nuzzo, Simona; Guglielmelli, Paola; Pennucci, Valentina; Prudente, Zelia; Ruberti, Samantha; Rontauroli, Sebastiano; Norfo, Ruggiero; Bianchi, Elisa; Bogani, Costanza; Rotunno, Giada; Fanelli, Tiziana; Mannarelli, Carmela; Rosti, Vittorio; Salmoiraghi, Silvia; Pietra, Daniela; Ferrari, Sergio; Barosi, Giovanni; Rambaldi, Alessandro; Cazzola, Mario; Bicciato, Silvio; Tagliafico, Enrico; Vannucchi, Alessandro M; Manfredini, Rossella
abstract
Primary myelofibrosis (PMF) is a Myeloproliferative Neoplasm (MPN) characterized by megakaryocyte hyperplasia, progressive bone marrow fibrosis, extramedullary hematopoiesis and transformation to Acute Myeloid Leukemia (AML). A number of phenotypic driver (JAK2, CALR, MPL) and additional subclonal mutations have been described in PMF, pointing to a complex genomic landscape. To discover novel genomic lesions that can contribute to disease phenotype and/or development, gene expression and copy number signals were integrated and several genomic abnormalities leading to a concordant alteration in gene expression levels were identified. In particular, copy number gain in the polyamine oxidase (PAOX) gene locus was accompanied by a coordinated transcriptional up-regulation in PMF patients. PAOX inhibition resulted in rapid cell death of PMF progenitor cells, while sparing normal cells, suggesting that PAOX inhibition could represent a therapeutic strategy to selectively target PMF cells without affecting normal hematopoietic cells' survival. Moreover, copy number loss in the chromatin modifier HMGXB4 gene correlates with a concomitant transcriptional down-regulation in PMF patients. Interestingly, silencing of HMGXB4 induces megakaryocyte differentiation, while inhibiting erythroid development, in human hematopoietic stem/progenitor cells. These results highlight a previously un-reported, yet potentially interesting role of HMGXB4 in the hematopoietic system and suggest that genomic and transcriptional imbalances of HMGXB4 could contribute to the aberrant expansion of the megakaryocytic lineage that characterizes PMF patients.
2016
- miR-382-5p Controls Hematopoietic Stem Cell Differentiation Through the Downregulation of MXD1
[Articolo su rivista]
Zini, Roberta; Rossi, Chiara; Norfo, Ruggiero; Pennucci, Valentina; Barbieri, Greta; Ruberti, Samantha; Rontauroli, Sebastiano; Salati, Simona; Bianchi, Elisa; Manfredini, Rossella
abstract
microRNAs are key regulators of gene expression that control stem cell fate by posttranscriptional downregulation of hundreds of target genes through seed pairing in their 3' untranslated region. In fact, miRNAs tightly regulate fundamental stem cell processes, like self-renewal, proliferation, and differentiation; therefore, miRNA deregulation may contribute to the development of solid tumors and hematological malignancies. miR-382-5p has been found to be upregulated in patients with myeloid neoplasms, but its role in normal hematopoiesis is still unknown. In this study, we demonstrated that miR-382-5p overexpression in CD34(+) hematopoietic stem/progenitor cells (HSPCs) leads to a significant decrease of megakaryocyte precursors coupled to increase of granulocyte ones. Furthermore, by means of a computational analysis using different prediction algorithms, we identified several putative mRNA targets of miR-382-5p that are downregulated upon miRNA overexpression (ie, FLI1, GATA2, MAF, MXD1, RUNX1, and SGK1). Among these, we validated MXD1 as real target of miR-382-5p by luciferase reporter assay. Finally, we showed that MXD1 knockdown mimics the effects of miR-382-5p overexpression on granulocyte and megakaryocyte differentiation of CD34(+) cells. Overall, our results demonstrated that miR-382-5p expression favors the expansion of granulocyte lineage and impairs megakaryocyte commitment through MXD1 downregulation. Therefore, our data showed for the first time that the miR-382-5p/MXD1 axis plays a critical role in myelopoiesis by affecting the lineage choice of CD34(+) HSPCs.
2016
- The isopeptidase inhibitor 2cPE triggers proteotoxic stress and ATM activation in chronic lymphocytic leukemia cells
[Articolo su rivista]
Tomasella, Andrea; Picco, Raffaella; Ciotti, Sonia; Sgorbissa, Andrea; Bianchi, Elisa; Manfredini, Rossella; Benedetti, Fabio; Trimarco, Valentina; Frezzato, Federica; Trentin, Livio; Semenzato, Gianpietro; Delia, Domenico; Brancolini, Claudio
abstract
Relapse after treatment is a common and unresolved problem for patients suffering of the B-cell chronic lymphocytic leukemia (B-CLL). Here we investigated the ability of the isopeptidase inhibitor 2cPE to trigger apoptosis in leukemia cells in comparison with bortezomib, another inhibitor of the ubiquitin-proteasome system (UPS). Both inhibitors trigger apoptosis in CLL B cells and gene expression profiles studies denoted how a substantial part of genes up-regulated by these compounds are elements of adaptive responses, aimed to sustain cell survival. 2cPE treatment elicits the up-regulation of chaperones, proteasomal subunits and elements of the anti-oxidant response. Selective inhibition of these responses augments apoptosis in response to 2cPE treatment. We have also observed that the product of the ataxia telangiectasia mutated gene (ATM) is activated in 2cPE treated cells. Stimulation of ATM signaling is possibly dependent on the alteration of the redox homeostasis. Importantly ATM inhibition, mutations or down-modulation increase cell death in response to 2cPE. Overall this work suggests that 2cPE could offer new opportunities for the treatment of B-CLL.
2016
- Tie2 expressing monocytes in the spleen of patients with primary myelofibrosis
[Articolo su rivista]
Campanelli, R.; Fois, G.; Catarsi, P.; Poletto, V.; Villani, L.; Erba, B. G.; Maddaluno, L.; Jemos, B.; Salmoiraghi, S.; Guglielmelli, P.; Abbonante, V.; Di Buduo, C. A.; Balduini, A.; Iurlo, A.; Barosi, G.; Rosti, V.; Massa, M.; Vannucchi, A. M.; Balliu, M.; Bartalucci, N.; Bogani, C.; Bosi, A.; Calabresi, L.; Corbizzi Fattori, G.; Fanelli, T.; Fjerza, R.; Gesullo, F.; Mannarelli, C.; Merli, L.; Pacilli, A.; Pancrazzi, A.; Paoli, C.; Pieri, L.; Rotunno, G.; Sant'Antonio, E.; Bonetti, E.; Cazzola, M.; Ambaglio, I.; Bernasconi, P.; Casetti, C. I.; Catricala, S.; Elena, C.; Fugazza, E.; Galli, A.; Malcovati, L.; Milanesi, C.; Pascutto, C.; Pietra, D.; Ripamonti, F.; Rossi, M.; Rumi, E.; Dejana, E.; Breviario, F.; Corada, M.; Malinverno, M.; Rambaldi, A.; Chioda, G.; Ferrari, M. L.; Finazzi, G.; Finazzi, M. C.; Belotti, C.; Boroni, C.; Amaru, A.; Golay, J.; Bortoluzzi, S.; Bisognin, A.; Coppe, A.; Saccoman, C.; Manfredini, R.; Artuso, L.; Bernardis, I.; Bianchi, E.; Montanari, M.; Pennucci, V.; Prudente, Z.; Rontauroli, S.; Rossi, C.; Ruberti, S.; Salati, S.; Tagliafico, E.; Tenedini, E.; Zini, R.
abstract
Primary myelofibrosis (PMF) is a Philadelphia-negative (Ph-) myeloproliferative disorder, showing abnormal CD34 + progenitor cell trafficking, splenomegaly, marrow fibrosis leading to extensive extramedullary haematopoiesis, and abnormal neoangiogenesis in either the bone marrow or the spleen. Monocytes expressing the angiopoietin-2 receptor (Tie2) have been shown to support abnormal angiogenic processes in solid tumors through a paracrine action that takes place in proximity to the vessels. In this study we investigated the frequency of Tie2 expressing monocytes in the spleen tissue samples of patients with PMF, and healthy subjects (CTRLs), and evaluated their possible role in favouring spleen angiogenesis. We show by confocal microscopy that in the spleen tissue of patients with PMF, but not of CTRLs, the most of the CD14 + cells are Tie2 + and are close to vessels; by flow cytometry, we found that Tie2 expressing monocytes were Tie2 + CD14 low CD16 bright CDL62 - CCR2 - (TEMs) and their frequency was higher (p = 0.008) in spleen tissue-derived mononuclear cells (MNCs) of patients with PMF than in spleen tissue-derived MNCs from CTRLs undergoing splenectomy for abdominal trauma. By in vitro angiogenesis assay we evidenced that conditioned medium of immunomagnetically selected spleen tissue derived CD14 + cells of patients with PMF induced a denser tube like net than that of CTRLs; in addition, CD14 + Tie2 + cells sorted from spleen tissue derived single cell suspension of patients with PMF show a higher expression of genes involved in angiogenesis than that found in CTRLs. Our results document the enrichment of Tie2 + monocytes expressing angiogenic genes in the spleen of patients with PMF, suggesting a role for these cells in starting/maintaining the pathological angiogenesis in this organ.
2015
- Abnormal expression patterns of WT1-as, MEG3 and ANRIL long non-coding RNAs in CD34+ cells from patients with primary myelofibrosis and their clinical correlations
[Articolo su rivista]
Pennucci, Valentina; Zini, Roberta; Norfo, Ruggiero; Guglielmelli, Paola; Bianchi, Elisa; Salati, Simona; Sacchi, Giorgia; Prudente, Zelia; Tenedini, Elena; Ruberti, Samantha; Paoli, Chiara; Fanelli, Tiziana; Mannarelli, Carmela; Tagliafico, Enrico; Ferrari, Sergio; Vannucchi, ALESSANDRO MARIA; Manfredini, Rossella; Associazione Italiana per la Ricerca sul Cancro Gruppo Italiano Malattie Mieloproliferative, Investigators
abstract
Abnormal expression patterns of WT1-as, MEG3 and ANRIL long non-coding RNAs in CD34+ cells from patients with primary myelofibrosis and their clinical correlations.
2015
- MYB controls erythroid versus megakaryocyte lineage fate decision through the miR-486-3p-mediated downregulation of MAF
[Articolo su rivista]
Bianchi, E.; Bulgarelli, J.; Ruberti, S.; Rontauroli, S.; Sacchi, G.; Norfo, R.; Pennucci, V.; Zini, R.; Salati, S.; Prudente, Z.; Ferrari, S.; Manfredini, R.
abstract
The transcription factor MYB has a key role in hematopoietic progenitor cells (HPCs) lineage choice, by enhancing erythropoiesis at the expense of megakaryopoiesis. We previously demonstrated that MYB controls erythroid versus megakaryocyte lineage decision by transactivating KLF1 and LMO2 expression. To further unravel the molecular mechanisms through which MYB affects lineage fate decision, we performed the integrative analysis of miRNA and mRNA changes in MYB-silenced human primary CD34+ HPCs. Among the miRNAs with the highest number of predicted targets, we focused our studies on hsa-miR-486-3p by demonstrating that MYB controls miR-486-3p expression through the transactivation of its host gene, ankyrin-1 (ANK1) and that miR-486-3p affects HPCs commitment. Indeed, overexpression and knockdown experiments demonstrated that miR-486-3p supports the erythropoiesis while restraining the megakaryopoiesis. Of note, miR-486-3p also favors granulocyte differentiation while repressing the macrophage differentiation. To shed some light on the molecular mechanisms through which miR-486-3p affects HPCs lineage commitment, we profiled the gene expression changes upon miR-486-3p overexpression in CD34+ cells. Among the genes downregulated in miR-486-3p-overexpressing HPCs and computationally predicted to be miR-486-3p targets, we identified MAF as a miR-486-3p target by 3′UTR luciferase reporter assay. Noteworthy, MAF overexpression was able to partially reverse the effects of miR-486-3p overexpression on erythroid versus megakaryocyte lineage choice. Moreover, the MYB/MAF co-silencing constrained the skewing of erythroid versus megakaryocyte lineage commitment in MYB-silenced CD34+ cells, by restraining the expansion of megakaryocyte lineage while partially rescuing the impairment of erythropoiesis. Therefore, our data collectively demonstrate that MYB favors erythropoiesis and restrains megakaryopoiesis through the transactivation of miR-486-3p expression and the subsequent downregulation of MAF. As a whole, our study uncovers the MYB/miR-486-3p/MAF axis as a new mechanism underlying the MYB-driven control of erythroid versus megakaryocyte lineage fate decision.
2014
- C-Myb Restrains Megakaryopoiesis through the Hsa-MiR-486-3p-Driven Down-Regulation of C-Maf
[Abstract in Rivista]
Bianchi, Elisa; Bulgarelli, Jenny; Sacchi, Giorgia; Ruberti, Samantha; Norfo, Ruggiero; Rontauroli, Sebastiano; Pennucci, Valentina; Zini, Roberta; Salati, Simona; Prudente, Zelia; Ferrari, Sergio; Vannucchi, Alessandro M.; Manfredini, Rossella
abstract
INTRODUCTION
The transcription factor c-Myb plays a key role in human primary CD34+ hematopoietic progenitor cells (HPCs) lineage choice, by enhancing erythropoiesis at the expense of megakaryopoiesis. We previously demonstrated that c-Myb affects erythroid versus megakaryocyte lineage decision in part by transactivating KLF1 and LMO2 expression. To further unravel the molecular mechanisms through which c-myb affects lineage fate decision, we profiled the miRNA and mRNA changes in myb-silenced CD34+ HPCs.
METHODS
RNA from CD34+ HPCs transfected with c-myb-targeting/non targeting control synthetic siRNAs was collected 24 hours post-Nucleofection for a set of 5 independent experiments.
mRNA and miRNA expression for each sample were profiled by Affymetrix U219 GeneAtlas and Exiqon Human miRNome PCR Panel, respectively. miRNA/mRNA data were integrated by Ingenuity Pathway Analysis.
The effects of hsa-miR-486-3p overexpression and c-Maf silencing on CD34+ cells differentiation ability were studied by morphological and immunophenotypic analyses after liquid culture and by collagen-based clonogenic assay. Furthermore, gene expression changes in CD34+ cells upon hsa-miR-486-3p overexpression were profiled by Affymetrix U219.
RESULTS
The integrative analysis of miRNA/mRNA expression changes upon c-myb silencing in human CD34+ HPCs highlighted a set of 19 miRNA with 150 anticorrelated putative target mRNAs. Among the miRNAs down-regulated in myb-silenced progenitors with the highest number of predicted target mRNAs, we selected hsa-miR-486-3p based on the in vitro effects of its overexpression on HPCs commitment. Indeed, morphological and flow cytometric analyses after liquid culture showed that hsa-miR-486-3p overexpression in HPCs enhanced erythroid and granulocyte differentiation while restraining megakaryocyte and macrophage differentiation. Moreover, collagen-based clonogenic assay demonstrated a strong impairement megakaryocyte commitment upon hsa-miR-486-3p-overexpression in CD34+ cells.
Gene expression profiling of hsa-miR-486-3p overexpressing CD34+ cells enabled us to identify a set of 8 genes down-regulated and computationally predicted, putative hsa-miR-486-3p targets. Among them, we selected c-maf transcript as up-regulated upon myb silencing. Worth of note, c-maf silencing in CD34+ progenitor cells was able to reverse the affects of myb silencing on erythroid versus megakaryocyte lineage choice.
CONCLUSIONS
Integrative miRNA/mRNA analysis highlighted a set of miRNAs and anticorrelated putative target mRNAs modulated upon myb silencing, therefore potential players in myb-driven HPCs lineage choice. Among them, we demonstrated the hsa-miR-486-3p/c-maf pair as partially contributing to the effects of myb on HPCs commitment. Therefore, our data collectively identified myb-driven hsa-miR-486-3p up-regulation and subsequent c-maf down-regulation as a new molecular mechanism through which c-Myb favours erythropoiesis while restraining megakaryopoiesis.
2014
- miRNA-mRNA integrative analysis in primary myelofibrosis CD34+ cells: role of miR-155/JARID2 axis in abnormal megakaryopoiesis
[Articolo su rivista]
Norfo, Ruggiero; Zini, Roberta; Pennucci, Valentina; Bianchi, Elisa; Salati, Simona; Guglielmelli, Paola; Bogani, Costanza; Fanelli, Tiziana; Mannarelli, Carmela; Rosti, Vittorio; Pietra, Daniela; Salmoiraghi, Silvia; Bisognin, Andrea; Ruberti, Samantha; Rontauroli, Sebastiano; Sacchi, Giorgia; Prudente, Zelia; Barosi, Giovanni; Cazzola, Mario; Rambaldi, Alessandro; Bortoluzzi, Stefania; Ferrari, Sergio; Tagliafico, Enrico; Vannucchi, Alessandro M; Manfredini, Rossella; Associazione Italiana per la Ricerca sul Cancro Gruppo Italiano Malattie Mieloproliferative, Investigators
abstract
Primary myelofibrosis (PMF) is a myeloproliferative neoplasm characterized by megakaryocyte (MK) hyperplasia, bone marrow fibrosis, and abnormal stem cell trafficking. PMF may be associated with somatic mutations in JAK2, MPL, or CALR. Previous studies have shown that abnormal MKs play a central role in the pathophysiology of PMF. In this work, we studied both gene and microRNA (miRNA) expression profiles in CD34(+) cells from PMF patients. We identified several biomarkers and putative molecular targets such as FGR, LCN2, and OLFM4. By means of miRNA-gene expression integrative analysis, we found different regulatory networks involved in the dysregulation of transcriptional control and chromatin remodeling. In particular, we identified a network gathering several miRNAs with oncogenic potential (eg, miR-155-5p) and targeted genes whose abnormal function has been previously associated with myeloid neoplasms, including JARID2, NR4A3, CDC42, and HMGB3. Because the validation of miRNA-target interactions unveiled JARID2/miR-155-5p as the strongest relationship in the network, we studied the function of this axis in normal and PMF CD34(+) cells. We showed that JARID2 downregulation mediated by miR-155-5p overexpression leads to increased in vitro formation of CD41(+) MK precursors. These findings suggest that overexpression of miR-155-5p and the resulting downregulation of JARID2 may contribute to MK hyperplasia in PMF.
2014
- Targeted cancer exome sequencing reveals recurrent mutations in myeloproliferative neoplasms
[Articolo su rivista]
Tenedini, Elena; Bernardis, Isabella; Artusi, Valentina; Artuso, Lucia; Roncaglia, E.; Guglielmelli, P.; Pieri, L.; Bogani, C.; Biamonte, F.; Rotunno, G.; Mannarelli, C.; Bianchi, Elisa; Pancrazzi, A.; Fanelli, T.; MALAGOLI TAGLIAZUCCHI, Guidantonio; Ferrari, Sergio; Manfredini, Rossella; Vannucchi, A. M.; Tagliafico, Enrico
abstract
With the intent of dissecting the molecular complexity of Philadelphia-negative myeloproliferative neoplasms (MPN), we designed a target enrichment panel to explore, using next-generation sequencing (NGS), the mutational status of an extensive list of 2,000 cancer-associated genes and microRNAs. The genomic DNA of granulocytes and in-vitro-expanded CD3+ T-lymphocytes, as a germline control, was target-enriched and sequenced in a learning cohort of 20 MPN patients using Roche 454 technology. We identified 141 genuine somatic mutations, most of which were not previously described. To test the frequency of the identified variants, a larger validation cohort of 189 MPN patients was additionally screened for these mutations using Ion Torrent AmpliSeq NGS. Excluding the genes already described in MPN, for 8 genes (SCRIB, MIR662, BARD1, TCF12, FAT4, DAP3, POLG, and NRAS), we demonstrated a mutation frequency between 3 and 8%.
We also found that mutations at codon 12 of NRAS (NRASG12V and NRASG12D) were significantly associated, for primary myelofibrosis (PMF), with highest DIPSS-plus score categories. This association was then confirmed in 66 additional PMF patients composing a final dataset of 168 PMF showing an NRAS mutation frequency of 4.7%, which was associated with a worse outcome, as defined by the DIPSS plus score.
2013
- Abnormal expression of WT1-as, MEG3 and ANRIL long non-coding RNAs in primary myelofibrosis and their clinical correlates
[Abstract in Atti di Convegno]
Pennucci, Valentina; Zini, Roberta; Norfo, Ruggiero; Guglielmelli, P.; Bianchi, Elisa; Salati, Simona; Sacchi, G.; Prudente, Z.; Tenedini, Elena; Ruberti, S.; Rontauroli, S.; Paoli, C.; Fanelli, T.; Mannarelli, C.; Tagliafico, E.; Vannucchi, A. M.; Ferrari, S.; Manfredini, R.
abstract
Long non-coding RNAs (lncRNAs) are emerging as key regulators of gene expression in normal and cancer cells by recruiting chromatin remodeling complexes. Despite their characterization in several tumor types, little is known about the role of lncRNAs in malignant hematopoiesis. In particular, lncRNAs expression has never been investigated in cells from primary myelofibrosis (PMF) patients. PMF is a Philadelphia negative chronic Myeloproliferative Neoplasm (MPN) that originates from deregulated clonal proliferation of hematopoietic stem cell associated with overproduction of mature blood cells. Molecular basis underlying MPN pathogenesis were partially unraveled in 2005-2006 with the identification of somatic mutations of JAK2 and MPL, after which many other mutations were identified. Recently, several new molecular pathogenetic mechanisms were proposed, such as the aberrant expression of coding and non-coding RNAs. In order to identify other molecular abnormalities harbored by PMF patients, we investigated the expression of CDKN2B-antisense (ANRIL), MEG3 and WT1-antisense lncRNAs, previously described as potentially involved in hematological malignancies, in CD34+ cells from PMF patients. The results evidence that the majority of PMF samples displays a co-upregulation of WT1 and its antisense RNA compared to controls. These samples also show an increased MEG3 expression. In these patients, we found a correlation with high Dynamic International Prognostic Scoring System (DIPPS) plus score and elevated number of circulating CD34+ cells. Moreover, the expression pattern of CDKN2B/ANRIL distinguishes a group of patients characterized by an upregulation of CDKN2B, and, among these, a subgroup with downregulated ANRIL. Of note, this group of patients was characterized by a higher grade of bone marrow fibrosis and by the presence of JAK2V617F mutation. Our results suggest that a deregulated expression of these lncRNAs could play a role in PMF pathogenesis and progression.
2013
- Co-culture of hematopoietic stem/progenitor cells with human osteblasts favours mono/macrophage differentiation at the expense of the erythroid lineage
[Articolo su rivista]
Salati, Simona; Lisignoli, G; Manfredini, C; Pennucci, Valentina; Zini, Roberta; Bianchi, Elisa; Norfo, Ruggiero; Facchini, A; Ferrari, Sergio; Manfredini, Rossella
abstract
Hematopoietic stem cells (HSCs) are located in the bone marrow in a specific microenvironment referred as the hematopoietic stem cell niche, where HSCs interact with a variety of stromal cells. Though several components of the stem cell niche have been identified, the regulatory mechanisms through which such components regulate the stem cell fate are still unknown. In order to address this issue, we investigated how osteoblasts (OBs) can affect the molecular and functional phenotype of Hematopoietic Stem/Progenitor Cells (HSPCs) and vice versa. For this purpose, human CD34+ cells were cultured in direct contact with primary human OBs. Our data showed that CD34+ cells cultured with OBs give rise to higher total cell numbers, produce more CFUs and maintain a higher percentage of CD34+CD38- cells compared to control culture. Moreover, clonogenic assay and long-term culture results showed that co-culture with OBs induces a strong increase in mono/macrophage precursors coupled to a decrease in the erythroid ones. Finally, gene expression profiling (GEP) allowed us to study which signalling pathways were activated in the hematopoietic cell fraction and in the stromal cell compartment after coculture. Such analysis allowed us to identify several cytokine-receptor networks, such as WNT pathway, and transcription factors, as TWIST1 and FOXC1, that could be activated by co-culture with OBs and could be responsible for the biological effects reported above. Altogether our results indicate that OBs are able to affect HPSCs on 2 different levels: on one side, they increase the immature progenitor pool in vitro, on the other side, they favor the expansion of the mono/macrophage precursors at the expense of the erythroid lineage.
2013
- Integrative Analysis Of mRNA/miRNA Expression Profiles Identified JARID2 As a Shared Target Of Deregulated Mirnas In Primary Myelofibrosis
[Abstract in Rivista]
Zini, Roberta; Norfo, Ruggiero; Pennucci, Valentina; Bianchi, Elisa; Salati, Simona; Paola, Guglielmelli; Andrea, Bisognin; Vittorio, Rosti; Daniela, Pietra; Silvia, Salmoiraghi; Costanza, Bogani; Tiziana, Fanelli; Ruberti, Samantha; Sacchi, Giorgia; Prudente, Zelia; Giovanni, Barosi; Mario, Cazzola; Alessandro, Rambaldi; Stefania, Bortoluzzi; Ferrari, Sergio; Tagliafico, Enrico; Alessandro M., Vannucchi; Manfredini, Rossella
abstract
Ph-negative myeloproliferative neoplasms (MPNs) are characterized by many somatic mutations which have already been shown useful in the prognostic assessment of MPN patients [A.M. Vannucchi et al., Leukemia, 2013]. 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 [P. Guglielmelli et al., Exp Hematol, 2007]. 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). Among 726 differentially expressed genes (DEG) we found that several putative cancer markers (WT1, ANGPT1) and several genes related to PMF progression, i.e. involved in megakaryocyte (MK) differentiation (NFE2, CD9), and fibrosis development (DLK1, LEPR1), were significantly more expressed in PMF samples than in the normal counterpart. Similarly, as regards the miEP, among 74 human differentially expressed miRNAs (DEM) in PMF compared to controls we found the upregulation of several miRNAs associated with hematological malignancies or known as oncomiRs (i.e. hsa-miR-155-5p [S. Jiang et al., Cancer Res, 2010], miRNAs belonging to the miR-17-92 cluster [L. Venturini et al., Blood, 2007]), and other aberrantly expressed miRNAs never described in hematopoiesis (i.e. hsa-miR-335-5p).
Then, in order to construct regulatory networks of the functional human miRNA-target interactions, we performed an integrative analysis (IA) with Ingenuity Pathway analysis software, which combines the miRNA expression profile with computational predicted targets and with the gene expression data. IA between DEG and DEM disclosed a high number of predicted targets with anti-correlated expression to the trend of their targeting miRNAs. Of note, IA identified an interaction network (see Figure) in which the upregulated oncomirs miR-155-5p [R.M. O'Connel et al., J Exp Med, 2008], miR29a-3p [Y.C. Han et al., J Exp Med, 2010] and miR-19b-3p [K.J. Mavrakis et al., Nat Cell Biol, 2010] could explain the downregulation of targets whose lower expression was already described as involved in myeloproliferative phenotypes, such as NR4A3, CDC42, HMGB3. Additionally, IA disclosed the chromatin remodeler JARID2, which is frequently deleted in leukemic transformation of chronic myeloid malignancies, as a shared target of several upregulated miRNAs in PMF samples (i.e. miR-155-5p, miR-152-3p). Noteworthy, these miRNA-mRNA interactions were functionally confirmed by 3' UTR luciferase reporter assays.
Next, in order to characterize the role of JARID2 in PMF pathogenesis, we performed RNAi-mediated gene silencing experiments on CD34+ cells of healthy donor. Interestingly, inhibition of JARID2 expression produces in silenced cells a significant increase of CD41 expression when compared with control (28.6±3.1% vs 15.3±1.8% at day 8, 52.6±7.6% vs 35.4±4.9% at day 12 of serum free liquid culture) and a remarkable increase in CFU-MK colonies (59.6±6.5% vs 39.8±5.9%). The values are reported as mean ± 2S.E.M from five independent experiments.
Moreover, morphological analysis after May-Grunwald-Giemsa staining showed that JARID2 silencing induces in normal CD34+ cells a considerable enrichment in MK precursors at different stages of maturation.
This study allowed the identification of different networks possibly involved in PMF onset, highlighting the potential contribution of miRNAs to PMF pathogenesis. Furthermore, for the first time, we demonstrated that the JARID2 downregulation in CD34+ cells might contribute to the abnormal megakaryopoiesis typical of PMF.
2013
- Isolation of human keratinocyte stem cells and high-throughput screening approach for their characterization
[Abstract in Atti di Convegno]
Di Rocco, Antonio; Carulli, Sonia; Tenedini, Elena; Bianchi, Elisa; Tagliafico, Enrico; Manfredini, Rossella; Pellegrini, Graziella; DE LUCA, Michele
abstract
In the last three decades, regenerative medicine has opened new horizons for the in vitro
reconstruction of epithelial tissues and gene therapy treatment of skin disorders involving the
use of adult keratinocyte stem cells (KSCs). Although the ability to identify and isolate these cells
represents an important prerequisite for the development of these approaches, molecular markers
and their precise in vivo localization are still lacking. In order to define genes involved in the control
of stemness and commitment of KSCs, we developed a non-invasive, stem cell-preserving magnetic
micro beads based method in order to obtain a KSCs enriched population for high throughput
screening experiments. After 3T3 murine fibroblast feeder layer depletion from our keratinocyte
cultures, we isolated a subpopulation of basal epithelial cells on the basis of the different expression
levels of the a6β4 integrin. By using different approaches, including clonal analysis and p63 bright cells
quantification, we clearly showed that a6β4 integrin bright cells have greater growth potential and
clonogenic capacity compared to the remaining cell fraction and they include the KSCs population.
Comparing gene expression profile of a KSCs-enriched and a terminally differentiated cell population
coming from the same original primary cell culture we defined a set of genes most probably involved
in stemness maintenance. Ongoing gene profiling on single clone type will allow us to validate this
gene signature and to start functional studies on selected genes. Extending this approach to different
ectodermal derived tissues will provide a genome wide signature of the molecular pathways underlying
self-renewal, commitment and differentiation of KSCs.
2013
- Regulatory mRNA/microRNA networks in CD34+ cells from Primary Myelofibrosis
[Abstract in Atti di Convegno]
Pennucci, Valentina; Zini, Roberta; Norfo, Ruggiero; Ruberti, S.; Bianchi, Elisa; Salati, Simona; Gugliemelli, P.; Bisognin, A.; Rosti, V.; Pietra, D.; Ricci, C.; Fanelli, T.; Salmoiraghi, S.; Sacchi, G.; Prudente, Z.; Rontauroli, S.; Barosi, G.; Cazzola, M.; Bortoluzzi, S.; Tagliafico, E.; Vannucchi, A. M.; Ferrari, S.; Manfredini, R.
abstract
Primary myelofibrosis (PMF) is a clonal disorder of a hematopoietic stem cell included in the Philadelphia chromosome-negative chronic myeloproliferative disorders (MPD), together with polycythemia vera and essential thrombocythemia. The molecular mechanisms of these diseases were partially unravelled in 2005 with the identification of somatic gain-of-function of Janus kinase 2 (JAK2) and Thrombopoietin Receptor (MPL), after which many other mutated genes were found. Moreover, aberrant microRNA (miRNA) expression especially seems to add up to the molecular complexity of MPNs, as specific miRNA signatures discriminates MPN from normal donors. In order to have a comprehensive picture of miRNA deregulation and its relationship with differential gene expression in PMF cells, we obtained mRNA and miRNA profiles in the same CD34+ cells from 31 healthy donors and 42 PMF patients by means of Affymetrix technology. Several miRNAs involved in hematological malignancies or known as oncomirs were upregulated in PMF samples (hsa-miR-155-5p, miRNAs belonging to the miR-17-92 cluster), whereas other aberrantly expressed miRNAs have never been described in the hematological context (has-miR-335). Next, we carried out an in silico integrative analysis (IA) with Ingenuity Pathway Analysis software, which combines the computational predicted targets with the gene expression data to construct regulatory networks of the functional miRNA-mRNA interactions. Of note, IA identified a significant network in which the upregulated oncomirs miR-155-5p and miR29a-3p could explain the downregulation of targets whose lower expression was already described in myeloproliferative phenotypes (NR4A3, CDC42, HMGB3), and of the chromatin remodeler JARID2, which is frequently deleted in leukemic transformation of MPNs. This approach allowed the identification of different networks potentially involved in PMF onset and progression, highlighting the potential contribution of miRNAs to PMF pathogenesis.
2013
- Regulatory mRNA/microRNA networks in CD34+ cells from Primary Myelofibrosis
[Abstract in Atti di Convegno]
Norfo, Ruggiero; Zini, Roberta; Pennucci, Valentina; Ruberti, S.; Bianchi, Elisa; Salati, Simona; Gugliemelli, P.; Bisognin, A.; Rosti, V.; Pietra, D.; Ricci, C.; Fanelli, T.; Salmoiraghi, S.; Sacchi, G.; Prudente, Z.; Rontauroli, S.; Barosi, G.; Cazzola, M.; Bortoluzzi, S.; Tagliafico, E.; Vannucchi, A. M.; Ferrari, S.; Manfredini, R.
abstract
Primary myelofibrosis (PMF) is a clonal disorder of a hematopoietic stem cell included in the
Philadelphia chromosome-negative chronic myeloproliferative neoplasms (MPNs), together with
polycythemia vera and essential thrombocythemia. The molecular mechanisms of these diseases were
partially unravelled in 2005 with the identification of somatic gain-of-function of Janus kinase 2 (JAK2)
and Thrombopoietin Receptor (MPL), after which many other mutated genes were found. Moreover,
aberrant microRNA (miRNA) expression seems to add up to the molecular complexity of MPNs, as
specific miRNA signatures discriminates MPN cells from those of normal donors. In order to have a
comprehensive picture of miRNA deregulation and its relationship with differential gene expression in
PMF cells, we obtained mRNA and miRNA profiles in the same CD34+ cells from 31 healthy donors
and 42 PMF patients by means of Affymetrix technology. Several miRNAs involved in hematological
malignancies or known as oncomirs resulted upregulated in PMF samples (hsa-miR-155-5p, miRNAs
belonging to the miR-17-92 cluster), whereas other aberrantly expressed miRNAs have never been
described in the hematological context (hsa-miR-335). Next, we carried out an in silico integrative
analysis (IA) with Ingenuity Pathway Analysis software, which combines the computational predicted
targets with the gene expression data to construct regulatory networks of the functional miRNA-mRNA
interactions. Of note, IA identified a network potentially involved in PMF pathogenesis, in which the
upregulated oncomirs miR-155-5p and miR29a-3p could explain the downregulation of targets whose
lower expression was already described in myeloproliferative phenotypes (NR4A3, CDC42, HMGB3),
and of the chromatin remodeler JARID2, which is frequently deleted in leukemic transformation
of MPNs. Finally, we demonstrated the JARID2 downregulation in CD34+ cells plays a role in the
abnormal megakaryopoiesis, and contributes to PMF pathogenesis.
2012
- Purinergic signaling inhibits human acute myeloblastic leukemia cell proliferation, migration, and engraftment in immunodeficient mice
[Articolo su rivista]
Salvestrini, V; Zini, Roberta; Rossi, L; Gulinelli, S; Manfredini, Rossella; Bianchi, Elisa; Piacibello, W; Caione, L; Migliardi, G; Ricciardi, Mr; Tafuri, A; Romano, M; Salati, Simona; Di Virgilio, F; Ferrari, Sergio; Baccarani, M; Ferrari, D; Lemoli, R. M.
abstract
Extracellular ATP and UTP nucleotides increase the proliferation and engraftment potential of normal human hematopoietic stem cells via the engagement of purinergic receptors (P2Rs). In the present study, we show that ATP and UTP have strikingly opposite effects on human acute myeloblastic leukemia (AML) cells. Leukemic cells express P2Rs. ATP-stimulated leukemic cells, but not normal CD34+ cells, undergo down-regulation of genes involved in cell proliferation and migration, whereas cell-cycle inhibitors are up-regulated. Functionally, ATP induced the inhibition of proliferation and accumulation of AML cells, but not of normal cells, in the G0 phase of the cell cycle. Exposure to ATP or UTP inhibited AML-cell migration in vitro. In vivo, xenotransplantation experiments demonstrated that the homing and engraftment capacity of AML blasts and CD34+CD38- cells to immunodeficient mice BM was significantly inhibited by pretreatment with nucleotides. P2R-expression analysis and pharmacologic profiling suggested that the inhibition of proliferation by ATP was mediated by the down-regulation of the P2X7R, which is up-regulated on untreated blasts, whereas the inhibition of chemotaxis was mainly mediated via P2Y2R and P2Y4R subtypes. We conclude that, unlike normal cells, P2R signaling inhibits leukemic cells and therefore its pharmacologic modulation may represent a novel therapeutic strategy.
2012
- Regulatory Mrna/Microrna Networks in CD34+ Cells From Primary Myelofibrosis
[Abstract in Rivista]
Norfo, Ruggiero; Zini, Roberta; Pennucci, Valentina; Bianchi, Elisa; Salati, Simona; Guglielmelli, P.; Bisognin, A; Rosti, V.; Pietra, D.; Ricci, C.; Fanelli, T.; Salmoiraghi, S.; Sacchi, G.; Ruberti, S.; Barosi, G.; Cazzola, M.; Bortoluzzi, S.; Ferrari, S.; Tagliafico, E.; Vannucchi, A. M.; Manfredini, R.
abstract
Molecular mechanisms underlying Philadephia-negative myeloproliferative neoplasm (MPN) pathogenesis were partially unraveled in 2005–2006 with the identification of somatic gain-of-function of JAK2 and MPL, after which many other mutated genes were found. Recently, several new molecular pathogenetic mechanisms were identified. Among them, aberrant microRNA (miRNA) expression especially 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 (P. Guglielmelli et al., Exp Hematol, 2007). In order to have a comprehensive picture of miRNA deregulation and its relationship with differential gene expression in primary myelofibrosis (PMF) cells, we obtained coding gene- (GEP) and miRNA expression profiles (miEP) in the same CD34+ sample from 31 healthy donors and 42 PMF patients by means of Affymetrix technology (HG-U219 and miRNA 2.0 arrays). 726 genes were found as differentially expressed (DEG) (fold change contrast â{per thousand}¥2, false discovery rate â{per thousand}¤0.05) (FIG. 1) and further analysis pointed out that several DEG are related to processes involved in PMF progression as megakaryocyte (MK) differentiation, fibrosis and migration. Of interest, we found the upregulation of some putative cancer markers, such as WT1 (K. Inoue et al., Blood, 1994) and ANGPT1 (C.L. Cheng, Br J Cancer, 2011) whose expression has already been associated with poor prognosis in hematological neoplasms and in other malignancies.
Among the deregulated transcription factors, we detected several genes involved in CD34+ commitment, and potentially in their transformation, such as NFE-2 (C. LAbbaye et al., J Clin Invest, 1995) and KLF3 (A.P. Funnell, Mol Cell Biol, 2012). As regards miEP, we achieved a list of 74 human miRNAs modulated in PMF (DEM) (fold change contrast â{per thousand}¥1.5, false discovery rate â{per thousand}¤0.05), some of which associated with hematological malignancies or known as oncomirs are upregulated, i.e. hsa-miR-155-5p (S. Jiang, Cancer Res, 2010), miRNAs belonging to the miR-17–92 cluster (L. Venturini et al., Blood, 2007), whereas other aberrantly expressed miRNAs have never been described in any hematological context. Next, we performed an in silico integrative analysis (IA) with Ingenuity Pathway analysis software, which combines the computational predicted targets with the gene expression data, in order to construct regulatory networks of the functional human miRNA-target interactions. IA between DEG and DEM disclosed a high number of predicted targets with anti-correlated expression to the trend of their targeting miRNAs. This approach allowed the identification of different networks potentially involved in PMF onset and progression, such as MK differentiation and chromatin remodeling, highlighting the potential contribution of miRNAs to PMF pathogenesis.
In particular, the integrative analysis has identified an interaction network involving the oncomirs miR-155-5p and miR-29a-3p (R. M. O'Connel et al, J Exp Med, 2008, Y.C. Han et al, j Exp Med, 2010) and their targets (FIG. 2).
In this network the upregulation of miR-155-5p and mir-29a-3p could explain the negative regulation of two tumor suppressor genes, HBP1 and TP53INP1, and of SPTB1, CDC42 and KLF3, whose downregulation is involved in malignant hematopoiesis (L.Yang et al, Blood 2007). This network also shows the upregulation of some miRNAs whose function is unknown in the hematopoietic context as miR-335-5p, with the negative regulation of its predicted targets, NR4A3 and PRDM2, which are described as implicated in myeloproliferation (AM Ramirez-Herrick et al, Blood 2001).
The present findings lay the groundwork for functional in vitro validation of selected networks in normal and PMF CD34+ cells by means of DEG/DEM overexpression and silencing experiments; furthermore, expression data will b
2012
- Valproic acid triggers erythro/megakaryocyte lineage decision through induction of GFI1B and MLLT3 expression
[Articolo su rivista]
Zini, Roberta; Norfo, Ruggiero; Ferrari, Francesco; Bianchi, Elisa; Salati, Simona; Pennucci, Valentina; Sacchi, Giorgia; Carboni, Chiara; Ceccherelli, Gb; Tagliafico, Enrico; Ferrari, Sergio; Manfredini, Rossella
abstract
Histone deacetylase inhibitors represent a family of targeted anticancer compounds that are widely used against hematological malignancies. So far little is known about their effects on normal myelopoiesis. Therefore, in order to investigate the effect of histone deacetylase inhibitors on the myeloid commitment of hematopoietic stem/progenitor cells, we treated CD34(+) cells with valproic acid (VPA). Our results demonstrate that VPA treatment induces H4 histone acetylation and hampers cell cycle progression in CD34(+) cells sustaining high levels of CD34 protein expression. In addition, our data show that VPA treatment promotes erythrocyte and megakaryocyte differentiation. In fact, we demonstrate that VPA treatment is able to induce the expression of growth factor-independent protein 1B (GFI1B) and of mixed-lineage leukemia translocated to chromosome 3 protein (MLLT3), which are crucial regulators of erythrocyte and megakaryocyte differentiation, and that the up-regulation of these genes is mediated by the histone hyperacetylation at their promoter sites. Finally, we show that GFI1B inhibition impairs erythroid and megakaryocyte differentiation induced by VPA, while MLLT3 silencing inhibits megakaryocyte commitment only. As a whole, our data suggest that VPA sustains the expression of stemness-related markers in hematopoietic stem/progenitor cells and is able to interfere with hematopoietic lineage commitment by enhancing erythrocyte and megakaryocyte differentiation and by inhibiting the granulocyte and mono-macrophage maturation.
2010
- c-Myb supports erythropoiesis by transactivating KLF1 and LMO2 expression
[Abstract in Atti di Convegno]
Bianchi, Elisa; Zini, Roberta; Salati, Simona; Tenedini, Elena; Norfo, Ruggiero; Ferrari, Sergio; Manfredini, Rossella
abstract
The c-Myb transcription factor is highly expressed in immature hematopoietic cells and down-regulated during
differentiation. c-myb is essential for the hematopoietic development, as c-myb-/- mice die at E15 due to failure of fetal
hepatic erythropoiesis. To gain further insights into the role of c-myb during the hematopoietic lineage commitment, we
studied the effects of c-Myb silencing in human CD34+ hematopoietic stem/progenitor cells. c-Myb silencing in CD34+
cells was performed by transfection of siRNAs using the Amaxa Nucleofector® Technology. In order to keep c-Myb
expression silenced for all the commitment phase of CD34+ cells, each sample was nucleofected 3 times, once a day.
Moreover, to exclude non-specific effects of siRNA nucleofection, for each experiment, together with the sample
transfected with the siRNAs targeting c-Myb, one sample electroporated without siRNAs and one transfected with a
non-targeting siRNA were performed. c-Myb silencing effects on CD34+ cells differentiation ability were studied by
methylcellulose and collagen-based clonogenic assays and by morphological and immunophenotypic analyses after
liquid culture. Furthermore, we investigated by microarray analysis the changes in gene expression induced by c-Myb
silencing. Methylcellulose assay revealed a remarkable increase of the percentage of monocyte (CFU-M) colonies and a
decrease of the erythroid ones (BFU-E) in c-Myb-silenced CD34+ cells. Moreover, collagen-based clonogenic assay
demonstrated that c-Myb silencing strongly enhances the megakaryocyte commitment of CD34+ cells. In agreement
with these data, flow cytometric analysis showed an increase in mono-macrophage and megakaryocyte fractions in cmyb-silenced
cells, while the erythroid population was strongly decreased. Morphological evaluation of May
Grunwald-Giemsa stained cytospins further supported the conclusion that c-myb silencing forces the CD34+ cells
commitment towards the macrophage and megakaryocyte lineages at the expense of the erythroid one. Gene expression
profiling of c-Myb silenced CD34+ cells enabled us to identify new putative targets which can account for c-Myb
knockdown effects. Indeed, Chromatin Immunoprecipitation and Luciferase reporter assay demonstrated that c-Myb
binds to KLF1 and LMO2 promoters and transactivates their expression. Functional rescue experiments showed that the
retroviral vector-mediated overexpression of KLF1 and LMO2 transcription factors in c-Myb silenced cells is able to
rescue, at least in part, the impaired erythroid differentiation. Our data collectively demonstrate that c-Myb plays a
pivotal role in human primary hematopoietic stem/progenitor cells lineage commitment, by enhancing erythropoiesis at
the expense of megakaryocyte diffentiation. In particular, we identified c-Myb-driven KLF1 and LMO2 transactivation
as the molecular mechanism through which c-Myb regulates erythroid versus megakaryocyte lineage fate decision.
2010
- c-Myb supports erythropoiesis through the transactivation of KLF1 and LMO2 expression.
[Articolo su rivista]
Bianchi, Elisa; Zini, Roberta; Salati, Simona; Tenedini, Elena; Norfo, Ruggiero; Tagliafico, Enrico; Manfredini, Rossella; Ferrari, Sergio
abstract
The c-Myb transcription factor is highly expressed in immature hematopoietic cells and down-regulated during differentiation. To define its role during the hematopoietic lineage commitment, we silenced c-Myb in human CD34+ hematopoietic stem/progenitor cells. Noteworthy, c-myb silencing increased the commitment capacity towards the macrophage and megakaryocyte lineages, while erythroid differentiation was impaired, as demonstrated by clonogenic assay, morphological and immunophenotypic data. Gene expression profiling and computational analysis of promoter regions of genes modulated in c-Myb-silenced CD34+ cells identified the transcription factors KLF1 and LMO2 as putative targets which can account for c-Myb knockdown effects. Indeed, Chromatin Immunoprecipitation and Luciferase reporter assay demonstrated that c-Myb binds to KLF1 and LMO2 promoters and transactivates their expression. Consistently, the retroviral vector-mediated overexpression of either KLF1 or LMO2 partially rescued the defect in erythropoiesis caused by c-Myb silencing, while only KLF1 was also able to repress the megakaryocyte differentiation enhanced in Myb-silenced CD34+ cells. Our data collectively demonstrate that c-Myb plays a pivotal role in human primary hematopoietic stem/progenitor cells lineage commitment, by enhancing erythropoiesis at the expense of megakaryocyte diffentiation. Indeed, we identified KLF1 and LMO2 transactivation as the molecular mechanism underlying Myb-driven erythroid versus megakaryocyte cell fate decision.
2010
- HGM 2010 Programme / Abstract
[Abstract in Rivista]
Tenedini, Elena; Roncaglia, Enrica; Ferrari, Francesco; Orlandi, Claudia; Bianchi, Elisa; Bicciato, Silvio; Tagliafico, Enrico; Ferrari, Sergio
abstract
Hematopoiesis entails a series of hierarchically organized events that proceed throughout cell specification and terminates with cell differentiation. Commitment needs the transcription factors effort that, in concert with microRNAs, drives cell fate and responds to promiscuous patterns of gene expression by turning-on lineage-specific genes and repressing alternate lineage transcripts. We obtained microRNAs profiles from human CD34+ hematopoietic progenitor cells and in-vitro differentiated erythroblasts, megakaryoblasts, monoblasts and myeloblasts precursors, that we analyzed together with their gene expression profiles. The integrated analysis of microRNA-mRNA expression levels highlighted an inverse correlation between microRNAs specifically up-regulated in one single cell progeny and their putative target genes, which resulted down-regulated. Among the up-regulated lineage-enriched microRNAs, hsa-miR-299-5p emerged as having a role in controlling CD34+ progenitors fate, grown in multilineage culture conditions. Gain- and loss-of-function experiments revealed that hsa-miR-299-5p participates the regulation of hematopoietic progenitors fate, modulating megakaryocytic-granulocytic versus erythroid-monocytic differentiation.
2010
- Integrated analysis of microRNA and mRNA expression profiles in physiological myelopoieis: role of hsa-miR-299-5p in CD34+ progenitor cells commitment
[Abstract in Atti di Convegno]
Tenedini, Elena; Roncaglia, Enrica; Ferrari, Francesco; Orlandi, Claudia; Bianchi, Elisa; Bicciato, Silvio; Tagliafico, Enrico; Ferrari, Sergio
abstract
Cell fate decisions in the hematopoietic system appear to be directed by an antagonistic or synergistic interplay of
transcription factors that pivot immature blood progenitors for cell specification. Multipotent progenitors initially
trigger a promiscuous transcriptional program and, as soon as they commit to a restricted fate, they reinforce unilineage
gene expression and withdraw transcripts affiliated with alternative blood cell types. MicroRNAs appear to be
especially pertinent in driving this particular behavior representing a new component of the hematopoietic gene
regulatory network. In fact, the archetypal microRNA can potentially regulate hundreds of genes even if most targets
contain isolated microRNA recognition sites that may be inadequate for complete gene silencing. According to Bartel’s
theory, microRNAs mediated post-transcriptional control offers a more flexible and rapid way of tuning genes
compared to transcriptional control (Bartel DP and Chen CZ, Nat Rev Genet 2004). These issues encouraged some
investigators to explore the association of microRNAs and genes expression profiles obtained from the same cell type
and advocated that microRNAs evolved to regulate gene expression programs and remove gene products unnecessary or
potentially dangerous more rapidly than might occur by natural decay. Although many studies addressed the role of
microRNAs during the normal myeloid differentiation process, only Georgantas and co-workers focused onto the
impact of microRNAs on mRNA expression levels but limited the analyses to data obtained from human CD34+
stem/progenitor cells (Georgantas RW 3rd et al, PNAS 2007). In order to shed light onto the interplay of mRNAs and
microRNAs during the normal myeloid commitment and verify that increased expression of a microRNA is skillful to
modulate the levels of corresponding target mRNAs, we obtained microRNAs profiles from CD34+ hematopoietic
progenitor cells (CD34 HPCs) and in-vitro differentiated precursors: erythroblasts, megakaryoblasts, monoblasts and
myeloblasts (ERY, MKC, MONO and MYELO). We therefore analyzed these microRNA expression profiles together
with the gene expression profiles of the same populations and observed that for the most part of the microRNAs
specifically up-regulated in one single progeny an inverse correlation between microRNAs and down-regulated putative
targets expression levels occurs, i.e. down-regulated genes showed an enrichment for the conserved putative targets of
up-regulated microRNA. Among these microRNAs, hsa-miR-299-5p emerged as an interesting candidate to
demonstrate how the integrated analysis of microRNA and mRNA expression data can help shedding light on the
regulatory mechanisms governing cell differentiation. In particular, we used hsa-miR-299-5p to prove that the forced
expression of a single lineage-specific microRNA is able to control the cell fate of CD34 HPCs grown in multilineage
culture conditions. Clonogenic and liquid culture differentiation assays after gain- and loss-of-function experiments
revealed that indeed hsa-miR-299-5p regulates hematopoietic progenitors fate modulating megakaryocytic-granulocytic
versus erythroid-monocytic development.
2010
- Integrated analysis of microRNA and mRNA expression profiles in physiological myelopoiesis: role of hsa-mir-299-5p in CD34+ progenitor cells commitment
[Articolo su rivista]
Tenedini, Elena; Roncaglia, Enrica; Orlandi, Claudia; Bianchi, Elisa; Bicciato, Silvio; Tagliafico, Enrico; Ferrari, Sergio; Ferrari, Francesco
abstract
Hematopoiesis entails a series of hierarchically organized events that proceed throughout cell specification and terminates with cell differentiation. Commitment needs the transcription factors' effort, which, in concert with microRNAs, drives cell fate and responds to promiscuous patterns of gene expression by turning on lineage-specific genes and repressing alternate lineage transcripts. We obtained microRNA profiles from human CD34+ hematopoietic progenitor cells and in vitro differentiated erythroblasts, megakaryoblasts, monoblasts and myeloblast precursors that we analyzed together with their gene expression profiles. The integrated analysis of microRNA-mRNA expression levels highlighted an inverse correlation between microRNAs specifically upregulated in one single-cell progeny and their putative target genes, which resulted in downregulation. Among the upregulated lineage-enriched microRNAs, hsa-miR-299-5p emerged as having a role in controlling CD34+ progenitor fate, grown in multilineage culture conditions. Gain- and loss-of-function experiments revealed that hsa-miR-299-5p participates in the regulation of hematopoietic progenitor fate, modulating megakaryocytic-granulocytic versus erythroid-monocytic differentiation
2010
- Integrated analysis of microRNA
and mRNA expression profiles
in physiological myelopoieis:
role of hsa-mir-299-5p in CD34+
progenitor cells commitment
[Abstract in Atti di Convegno]
Tenedini, Elena; Roncaglia, Enrica; Ferrari, F; Orlandi, C; Bianchi, Elisa; Bicciato, Silvio; Tagliafico, Enrico; Ferrari, Sergio
abstract
Hematopoiesis entails a series of hierarchically organized events that proceed throughout cell specification and terminates with cell differentiation. Commitment needs the transcription factors effort that, in concert with microRNAs, drives cell fate and responds to promiscuous patterns of gene expression by turning-on lineage-specific genes and repressing alternate lineage transcripts. We obtained microRNAs profiles from human CD34+ hematopoietic progenitor cells and in-vitro differentiated erythroblasts, megakaryoblasts, monoblasts and myeloblasts precursors, that we analyzed together with their gene expression profiles. The integrated analysis of microRNA-mRNA expression levels highlighted an inverse correlation between microRNAs specifically up-regulated in one single cell progeny and their putative target genes, which resulted down-regulated. Among the up-regulated lineage-enriched microRNAs, hsa-miR-299-5p emerged as having a role in controlling CD34+ progenitors fate, grown in multilineage culture conditions. Gain- and loss-of-function experiments revealed that hsa-miR-299-5p participates the regulation of hematopoietic progenitors fate, modulating megakaryocytic-granulocytic versus erythroid-monocytic differentiation.
2009
- Mechanistic insight into WEB-2170-induced apoptosis in human acute myelogenous leukemia cells. the crucial role of PTEN.
[Articolo su rivista]
Cellai, C; Laurenzana, A; Bianchi, Elisa; Sdelci, S; Manfredini, Rossella; Vannucchi, Am; Caporale, R; Balliu, M; Mannelli, F; Ferrari, Sergio; Bosi, A; Miniati, D; Cocco, Pl; Veronneau, S; Stankova, J; Paoletti, F.
abstract
OBJECTIVE:This study aimed to investigate the mechanisms of action of WEB-2170, an inverse agonist of platelet-activating factor receptor, capable of inducing apoptosis in human acute myelogenous leukemia (AML) cells.MATERIAL AND METHODS:Gene expression profiling followed by cytofluorimetric, morphologic, and biologic analyses were used to monitor WEB-2170 effects in AML cell lines (ie, NB4, KG1, NB4-MR4, THP1, and U937) and blasts from patients with different AML (M0-M5) subtypes. PTEN silencing with small interfering RNA was also performed.RESULTS:We have demonstrated that drug-mediated cytostasis/apoptosis in NB4 cells is characterized by upregulation of cyclin G2, p21/WAF1, NIX, TNF-alpha, and PTEN expression, and downregulation of cyclin D2 and BCL2 expression. We observed an increase in PTEN protein accompanied by a decrease in phospho-extracellular signal-regulated kinase 2 (ERK2) and phospho-AKT, and by forkhead box O3a (FOXO3a) cytoplasmic-nuclear translocation; the mitochondrial cytochrome C release and PARP cleavage marked the late apoptotic steps. We have found that WEB-2170 triggered apoptosis in NB4, KG1, and NB4-MR4 cells where PTEN was expressed, but not in THP1 and U937 cells where PTEN was absent. Finally, we show that PTEN silencing in NB4 cells by PTEN-specific small interfering RNA resulted in a significant reduction of drug-induced apoptosis.CONCLUSION:We demonstrated that WEB-2170 is a powerful antileukemic agent with interesting translational opportunities to treat AML and described mechanisms of drug-induced intrinsic and extrinsic apoptosis both in AML cell lines and blasts from AML patients by addressing PTEN as the master regulator of the whole process.
2009
- Molecular and functional analysis of the stem cell compartment of chronic myelogenous leukemia reveals the presence of a CD34- cell population with intrinsic resistance to imatinib
[Articolo su rivista]
Lemoli, Rm; Salvestrini, V; Bianchi, Elisa; Bertolini, F; Fogli, M; Amabile, M; Tafuri, A; Salati, Simona; Zini, Roberta; Testoni, N; Rabascio, C; Rossi, L; Martin Padura, I; Castagnetti, F; Marighetti, P; Martinelli, G; Baccarani, M; Ferrari, Sergio; Manfredini, Rossella
abstract
We show the molecular and functional characterization of a novel population of lineage-negative CD34-negative (Lin–CD34–) hematopoietic stem cells from chronic myelogenous leukemia (CML) patients at diagnosis. Molecular karyotyping and quantitative analysis of BCR-ABL transcript demonstrated that approximately one-third of CD34– cells are leukemic. CML Lin–CD34– cells showed kinetic quiescence and limited clonogenic capacity. However, stroma-dependent cultures induced CD34 expression on some cells and cell cycling, and increased clonogenic activity and expression of BCR-ABL transcript. Lin–CD34– cells showed hematopoietic cell engraftment rate in 2 immunodeficient mouse strains similar to Lin-CD34+ cells, whereas endothelial cell engraftment was significantly higher. Gene expression profiling revealed the down-regulation of cell-cycle arrest genes and genes involved in antigen presentation and processing, while the expression of genes related to tumor progression, such as angiogenic factors, was strongly up-regulated compared with normal counterparts. Phenotypic analysis confirmed the significant down-regulation of HLA class I and II molecules in CML Lin–CD34– cells. Imatinib mesylate did not reduce fusion transcript levels, BCR-ABL kinase activity, and clonogenic efficiency of CML Lin–CD34– cells in vitro. Moreover, leukemic CD34– cells survived exposure to BCR-ABL inhibitors in vivo. Thus, we identified a novel CD34– leukemic stem cell subset in CML with peculiar molecular and functional characteristics.
2008
- Role of CD34 antigen in myeloid differentiation of human hematopoietic progenitor cells
[Articolo su rivista]
Salati, Simona; Zini, Roberta; Bianchi, Elisa; Testa, Anna; Mavilio, Fulvio; Manfredini, Rossella; Ferrari, Sergio
abstract
CD34 is a transmembrane protein that is strongly expressed on hematopoietic stem/progenitor cells (HSCs); despite its importance as a marker of HSCs, its function is still poorly understood, although a role in cell adhesion has been demonstrated. To characterize the function of CD34 antigen on human HSCs, we examined, by both inhibition and overexpression, the role of CD34 in the regulation of HSC lineage differentiation. Our results demonstrate that CD34 silencing enhances HSC granulocyte and megakaryocyte differentiation and reduces erythroid maturation. In agreement with these results, the gene expression profile of these cells reveals the upregulation of genes involved in granulocyte and megakaryocyte differentiation and the downregulation of erythroid genes. Consistently, retroviral-mediated CD34 overexpression leads to a remarkable increase in erythroid progenitors and a dramatic decrease in granulocyte progenitors, as evaluated by clonogenic assay. Together, these data indicate that the CD34 molecule promotes the differentiation of CD34+ hematopoietic progenitors toward the erythroid lineage, which is achieved, at least in part, at the expense of granulocyte and megakaryocyte lineages.
2008
- Silencing CD34 antigen in human hematopoietic stem cells
[Articolo su rivista]
Zini, Roberta; Salati, Simona; Bianchi, Elisa; Ferrari, Sergio; Manfredini, Rossella
abstract
CD34 is a highly glycosylated transmembrane protein strongly expressed on hematopoietic stem/progenitor cells (HSPCs); despite its importance as a marker of HSPCs, its function is still poorly understood, even if a role in cell adhesion has been demonstrated. In order to characterize the function of CD34 antigen in human HSPCs, we evaluated by small interfering RNAs (siRNAs) mediated gene silencing the role of CD34 antigen in HSPCs differentiation. By using the Nucleofection Amaxa technology for siRNA transfection in HSPCs, we obtained a rapid and effective down-regulation of the CD34 antigen. In this paper, we have demonstrated that CD34 silencing in HSPCs enhances their granulocyte and megakaryocyte differentiation and reduces erythroid maturation as shown by clonogenic assay, morphological analysis and expression of differentiation markers. In agreement with these results, the gene expression profile of HSPCs-silenced cells reveals the up-regulation of genes involved in granulocyte and megakaryocyte commitment and the down-regulation of erythroid genes. These data indicate that CD34 transmembrane protein promotes the differentiation of CD34+ hematopoietic progenitors towards the erythroid lineage at the expense of granulocyte and megakaryocyte ones.
2007
- Eosinophils, but not neutrophils, exibit an efficient DNA repair machinary and high nucleolar activity
[Articolo su rivista]
Salati, Simona; Bianchi, Elisa; Zini, Roberta; Tenedini, Elena; Quaglino, Daniela; Manfredini, Rossella; Ferrari, Sergio
abstract
BACKGROUND AND OBJECTIVES: Traditionally eosinophils have been considered terminally differentiated cells that play a role in host protection against parasites. However, there is some evidence showing that eosinophils are, in fact, multifunctional leukocytes involved in inflammatory responses, as well as in tissue homeostasis. We characterized the transcriptome profile of human eosinophils, and, for the purpose of comparison, the transcriptome profile of neutrophils, monocytes and hematopoietic progenitor cells. Moreover, we studied the activation of selected cellular processes for which a significant differential expression was demonstrated. DESIGN AND METHODS: We profiled gene expression using Affymetrix GeneChips. DNA repair capacity was tested using the comet assay. Nucleoli and their activity were characterized by transmission electron microscopy analysis, silver staining of nucleolus regions (AgNOR) and RNA staining. RESULTS: Gene expression profiling showed that eosinophils appear hierarchically closer to monocytes than to neutrophils. Gene ontology mapping of differentially expressed genes revealed that eosinophils express categories very similar to those expressed by monocytes, related to DNA repair and nucleolar functions. Moreover, our data show that eosinophils and monocytes maintain the ability to repair both double and single strand DNA breaks, whereas neutrophils lack this capacity. Furthermore, eosinophils exhibit nucleolar activity, which is lacking in neutrophils, but resembles that in monocytes. INTERPRETATION AND CONCLUSIONS: The presence of large, active nucleoli in eosinophils, coupled to marked activity of DNA repair systems, suggests that eosinophils are not terminally differentiated cells. Indeed, their transcriptome profile and functional properties are more similar to those of non-terminally differentiated cells such as monocytes, rather than to neutrophils.
2007
- Molecular profiling of CD34+ cells in idiopathic myelofibrosis identifies a set of disease-associated genes and reveals the clinical significance of Wilms' tumor gene 1 (WT1)
[Articolo su rivista]
Guglielmelli, P; Zini, Roberta; Bogani, C; Salati, Simona; Pancrazzi, A; Bianchi, Elisa; Mannelli, F; Ferrari, Sergio; Le Bousse Kerdilès, Mc; Bosi, A; Barosi, G; Migliaccio, Ar; Manfredini, Rossella; Vannucchi, A. M.
abstract
This study was aimed at the characterization of a gene expression signature of the pluripotent hematopoietic CD34(+) stem cell in idiopathic myelofibrosis (IM), which would eventually provide novel pathogenetic insights and/or diagnostic/prognostic information. Aberrantly regulated genes were revealed by transcriptome comparative microarray analysis of normal and IM CD34(+) cells; selected genes were also assayed in granulocytes. One-hundred seventy four differentially expressed genes were identified and in part validated by quantitative polymerase chain reaction. Altered gene expression was corroborated by the detection of abnormally high CD9 or CD164, and low CXCR4, membrane protein expression in IM CD34(+) cells. According to class prediction analysis, a set of eight genes (CD9, GAS2, DLK1, CDH1, WT1, NFE2, HMGA2, and CXCR4) properly recognized IM from normal CD34(+) cells. These genes were aberrantly regulated also in IM granulocytes that could be reliably differentiated from control polycythemia vera and essential thrombocythemia granulocytes in 100% and 81% of cases, respectively. Abnormal expression of HMGA2 and CXCR4 in IM granulocytes was dependent on the presence and the mutational status of JAK2(V617F) mutation. The expression levels of both CD9 and DLK1 were associated with the platelet count, whereas higher WT1 expression levels identified IM patients with more active disease, as revealed by elevated CD34(+) cell count and higher severity score. In conclusion, molecular profiling of IM CD34(+) cells uncovered a limited number of genes with altered expression that, beyond their putative role in disease pathogenesis, are associated with patients' clinical characteristics and may have potential prognostic application.
2006
- IDENTIFICATION OF A MOLECULAR SIGNATURE PREDICTIVE OF REFRACTORINESS IN ACUTE MYELOID LEUKEMIA
[Abstract in Atti di Convegno]
Tenedini, Elena; Tagliafico, Enrico; Manfredini, Rossella; Ferrari, Francesco; Roncaglia, Enrica; Fantoni, Luca; Grande, Alexis; Parenti, Sandra; ZANOCCO MARANI, Tommaso; Gemelli, Claudia; Tatiana Vignudelli, Tatiana; Montanari, Monica; Zini, Roberta; Salati, Simona; Bianchi, Elisa; Bicciato, Silvio; Ferrari, Sergio
abstract
Acute Myeloid Leukemia (AML) blast cells are immature committed myeloid cells unable to spontaneously undergo terminal maturation, characterized by heterogeneous sensitivity to natural differentiation inducers. No data are available so far by which infer the AML’s response to differentiating therapy. Thus, we have initially profiled by GeneChip arrays the gene expression of several AML cell lines: they derived by the original blast cell populations and are still characterized by the same immunophenotype, retain a different sensitivity or resistance to All-Trans Retinoic-Acid (ATRA) and Vitamin-D3 (VD) and never undergo spontaneously terminal maturation. Here we show that differences exist by which predict the cell line differentiation fate. Next we constructed a signature able to predict resistance or sensitivity to the differentiation induction and tested it, using a TaqMan platform, for its capability to predict the in-vitro response of 28 VD or ATRA treated AML blast cell populations. Finally, by a meta-analysis of public available microarray data we demonstrated that our signature of 11 genes, among them is particularly intriguing the presence of Meis1 and ID3, that was formerly designed to identify differentiation therapy resistant populations, turned out to be a good classifier for clusters of patients known to have poor prognostic significance.
2006
- Identification of a molecular signature predictive of sensitivity to differentiation induction in acute myeloid leukemia
[Articolo su rivista]
Tagliafico, Enrico; Tenedini, Elena; Manfredini, Rossella; Grande, Alexis; Ferrari, F.; Roncaglia, Enrica; Bicciato, Silvio; Zini, Roberta; Salati, Simona; Bianchi, Elisa; Gemelli, Claudia; Montanari, Monica; Vignudelli, Tatiana; ZANOCCO MARANI, Tommaso; Parenti, Sandra; Paolucci, Paolo; Martinelli, G.; Piccaluga, P. P.; Baccarani, M.; Specchia, G.; Torelli, U.; Ferrari, Sergio
abstract
Acute myeloid leukemia (AML) blasts are immature committed myeloid cells unable to spontaneously undergo terminal maturation, and characterized by heterogeneous sensitivity to natural differentiation inducers. Here, we show a molecular signature predicting the resistance or sensitivity of six myeloid cell lines to differentiation induced in vitro with retinoic acid or vitamin D. The identified signature was further validated by TaqMan assay for the prediction of response to an in vitro differentiation assay performed on 28 freshly isolated AML blast populations. The TaqMan assay successfully predicts the in vitro resistance or responsiveness of AML blasts to differentiation inducers. Furthermore, performing a meta-analysis of publicly available microarray data sets, we also show the accuracy of our prediction on known phenotypes and suggest that our signature could become useful for the identification of patients eligible for new therapeutic strategies.
2005
- IDENTIFICATION OF A MOLECULAR SIGNATURE PREDICTIVE OF REFRACTORINESS IN ACUTE MYELOID LEUKEMIA
[Abstract in Atti di Convegno]
Tagliafico, Enrico; Tenedini, Elena; Manfredini, Rossella; Ferrari, Sergio; Roncaglia, Enrica; Fantoni, Luca; Grande, Alexis; Parenti, Sandra; ZANOCCO MARANI, Tommaso; Gemelli, Claudia; Vignudelli, Tatiana; Montanari, Monica; Zini, Roberta; Salati, Simona; Bianchi, Elisa; Bicciato, Silvio; Specchia, Giorgina; Martinelli, Giovanni; Baccarani, Michele; Piccaluga, Pier Paolo; Torelli, Umberto; Ferrari, Sergio
abstract
Acute Myeloid Leukemia (AML) blast cells are immature committed myeloid cells unable to spontaneously undergo terminal maturation, characterized by heterogeneous sensitivity to natural differentiation inducers. No data are available so far by which infer the AML’s response to differentiating therapy. Thus, we have initially profiled by GeneChip arrays the gene expression of several AML cell lines: they derived by the original blast cell populations and are still characterized by the same immunophenotype, retain a different sensitivity or resistance to ATRA and VD and never undergo spontaneously terminal maturation. Here we show that differences exist by which predict the cell line differentiation fate. Next we constructed a signature able to predict resistance or sensitivity to the differentiation induction and tested it, using a TaqMan platform, for its capability to predict the in-vitro response of 28 VD or ATRA treated AML blast cell populations. Finally, by a meta-analysis of public available microarray data we demonstrated that our signature, that was formerly designed to identify differentiation therapy resistant populations, turned out to be a good classifier for clusters of patients with citogenetically and molecularly defined lesions that are known to have poor prognostic significance.