RESUMO
INTRODUCTION: About 15% of people with a myeloproliferative neoplasm (MPN) are identified as MPN, unclassifiable using the 2016 WHO classification. METHODS: We tested whether persons with platelet concentration ≥450 × 10E+9/L, bone marrow megakaryocyte morphology typical of prefibrotic/early myelofibrosis (pre-MF), and no minor criteria of pre-MF should be classified as a distinct MPN subtype, clonal megakaryocyte dysplasia with isolated thrombocytosis (CMD-IT). RESULTS: 139 subjects meet these criteria who we compared with primary myelofibrosis (PMF) including 402 with pre-MF and 521 with overt myelofibrosis. CMD-IT subjects were more likely female and younger. They had lower frequencies of JAK2V617F compared with persons with PMF (55% vs. 70%; p < 0.001) and higher frequencies of CALR mutations (37% vs. 17%; p < 0.001). They also had lower frequency of variations associated with JAK2V617F susceptibility, JAK2 46/1 (35% vs. 47%; p = 0.021), and VEGFA rs3025039 (12% vs. 17%; p = 0.030). Subjects with CMD-IT had lower incidences of thrombotic events compared with those with pre-MF (9.7% vs. 26%; p < 0.001) and longer survival (median, not reached vs. 23 years; HR = 0.34 (0.10, 0.30); p < 0.001). CONCLUSION: Our data indicate CMD-IT is a distinct MPN subtype and should be included in the classification of myeloid neoplasms.
Assuntos
Transtornos Mieloproliferativos , Neoplasias , Mielofibrose Primária , Trombocitemia Essencial , Trombocitose , Feminino , Humanos , Mielofibrose Primária/diagnóstico , Mielofibrose Primária/genética , Megacariócitos , Trombocitemia Essencial/diagnóstico , Trombocitemia Essencial/genética , Mutação , Transtornos Mieloproliferativos/diagnóstico , Transtornos Mieloproliferativos/genética , Trombocitose/genética , Fenótipo , Janus Quinase 2/genética , Calreticulina/genéticaRESUMO
INTRODUCTION: In 1991, we reported 18 persons with a clinical-pathologic entity and termed atypical myeloproliferative disorder because they did not meet the contemporary diagnostic criteria for a myeloproliferative neoplasm. We sought to gain further knowledge on this disease entity. METHODS: This retrospective cohort study included consecutive subjects registered in the database of the Center for the Study of Myelofibrosis in Pavia, Italy, from 1998 to 2020 (June), and diagnosed with atypical myeloproliferative disorder according to our adjudicated criteria. We studied clinical, histological, cytogenetic, and molecular covariates and risks of thrombosis, disease progression, and death. Data were compared with those of concurrent subjects with prefibrotic myelofibrosis. RESULTS: Fifteen new subjects with atypical myeloproliferative disorder were identified. Seven were male. Median age was 50 years (IQR, 41-54 years). Thirteen were diagnosed with a synchronous symptomatic or incidentally detected thrombotic event. The bone marrow showed megakaryocyte hyperplasia with dysplasia. JAK2V617F was present in 10 subjects and CALR mutation in one. No other somatic mutations were identified in next generation sequencing. After a median follow-up of 101 months (IQR, 40-160 months), no subject had disease progression or blast transformation. Incidence of post-diagnosis or recurrent thrombosis was 3.9 events (95% confidence interval, 3.5-4.0) and 5.0 events (4.6-5.6) per 100 person-years. Features of subjects with atypical myeloproliferative disorder differed markedly from those of 546 subjects with prefibrotic myelofibrosis. CONCLUSION: Our data indicate that these 15 persons have a distinct myeloproliferative neoplasm. We propose naming this new disorder clonal megakaryocyte dysplasia with normal blood values.
Assuntos
Calreticulina , Neoplasias Hematológicas , Janus Quinase 2 , Megacariócitos , Mutação de Sentido Incorreto , Transtornos Mieloproliferativos , Adulto , Substituição de Aminoácidos , Medula Óssea/metabolismo , Medula Óssea/patologia , Calreticulina/genética , Calreticulina/metabolismo , Feminino , Neoplasias Hematológicas/sangue , Neoplasias Hematológicas/genética , Neoplasias Hematológicas/patologia , Humanos , Janus Quinase 2/genética , Janus Quinase 2/metabolismo , Masculino , Megacariócitos/metabolismo , Megacariócitos/patologia , Pessoa de Meia-Idade , Transtornos Mieloproliferativos/sangue , Transtornos Mieloproliferativos/genética , Transtornos Mieloproliferativos/patologia , Estudos Retrospectivos , TromboseRESUMO
Splenic hematopoiesis is a major feature in the course of myelofibrosis (MF). In fact, the spleen of patients with MF contains malignant hematopoietic stem cells retaining a complete differentiation program, suggesting both a pivotal role of the spleen in maintaining the disease and a tight regulation of hematopoiesis by the splenic microenvironment, in particular by mesenchymal stromal cells (MSCs). Little is known about splenic MSCs (Sp-MSCs), both in normal and in pathological context. In this work, we have in vitro expanded and characterized Sp-MSCs from 25 patients with MF and 13 healthy subjects (HS). They shared similar phenotype, growth kinetics, and differentiation capacity. However, MF Sp-MSCs expressed significant lower levels of nestin, and favored megakaryocyte (Mk) differentiation in vitro at a larger extent than their normal counterpart. Moreover, they showed a significant upregulation of matrix metalloprotease 2 (MMP2) and fibronectin 1 (FN1) genes both at mRNA expression and at protein level, and, finally, developed genetic abnormalities which were never detected in HS-derived Sp-MSCs. Our data point toward the existence of a defective splenic niche in patients with MF that could be responsible of some pathological features of the disease, including the increased trafficking of CD34+ cells and the expansion of the megakaryocytic lineage.
Assuntos
Células-Tronco Mesenquimais/patologia , Mielofibrose Primária/patologia , Baço/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos CD34 , Estudos de Casos e Controles , Movimento Celular , Proliferação de Células , Feminino , Fibronectinas/metabolismo , Hematopoese , Humanos , Masculino , Metaloproteinase 2 da Matriz/metabolismo , Megacariócitos/patologia , Pessoa de Meia-Idade , Nestina/metabolismo , Adulto JovemRESUMO
OBJECTIVES: The imbalance between effector and regulatory T (Treg) cells is crucial in the pathogenesis of autoimmune arthritis. Immune responses are often investigated in the blood because of its accessibility, but circulating lymphocytes are not representative of those found in inflamed tissues. This disconnect hinders our understanding of the mechanisms underlying disease. Our goal was to identify Treg cells implicated in autoimmunity at the inflamed joints, and also readily detectable in the blood upon recirculation. METHODS: We compared Treg cells of patients with juvenile idiopathic arthritis responding or not to therapy by using: (i) T cell receptor (TCR) sequencing, to identify clonotypes shared between blood and synovial fluid; (ii) FOXP3 Treg cell-specific demethylated region DNA methylation assays, to investigate their stability and (iii) flow cytometry and suppression assays to probe their tolerogenic functions. RESULTS: We found a subset of synovial Treg cells that recirculated into the bloodstream of patients with juvenile idiopathic and adult rheumatoid arthritis. These inflammation-associated (ia)Treg cells, but not other blood Treg cells, expanded during active disease and proliferated in response to their cognate antigens. Despite the typical inflammatory-skewed balance of immune mechanisms in arthritis, iaTreg cells were stably committed to the regulatory lineage and fully suppressive. A fraction of iaTreg clonotypes were in common with pathogenic effector T cells. CONCLUSIONS: Using an innovative antigen-agnostic approach, we uncovered a population of bona fide synovial Treg cells readily accessible from the blood and selectively expanding during active disease, paving the way to non-invasive diagnostics and better understanding of the pathogenesis of autoimmunity.
Assuntos
Artrite Juvenil/imunologia , Artrite Reumatoide/imunologia , Receptores de Antígenos de Linfócitos T/genética , Líquido Sinovial/citologia , Linfócitos T Reguladores/citologia , Adolescente , Adulto , Artrite Juvenil/sangue , Artrite Reumatoide/sangue , Criança , Pré-Escolar , Metilação de DNA , Feminino , Citometria de Fluxo , Genes Codificadores da Cadeia beta de Receptores de Linfócitos T/genética , Humanos , Masculino , Líquido Sinovial/imunologia , Membrana Sinovial , Linfócitos T Reguladores/imunologia , Adulto JovemRESUMO
Splanchnic vein thrombosis (SVT) is one of the vascular complications of myeloproliferative neoplasms (MPN). We designed a phase 2 clinical trial to evaluate safety and efficacy of ruxolitinib in reducing splenomegaly and improving disease-related symptoms in patients with MPN-associated SVT. Patients diagnosed with myelofibrosis (12 cases), polycythemia vera (5 cases) and essential thrombocythemia (4 cases) received ruxolitinib for 24 weeks in the core study period. Spleen volume was assessed by magnetic resonance imaging (MRI) and splanchnic vein circulation by echo-Doppler analysis. Nineteen patients carried JAK2V617F, one had MPLW515L, and one CALRL367fs*46 mutation. Eighteen patients had spleno-portal-mesenteric thrombosis, two had Budd-Chiari syndrome, and one had both sites involved; 16 patients had esophageal varices. Ruxolitinib was well tolerated with hematological toxicities consistent with those of patients without SVT and no hemorrhagic adverse events were recorded. After 24 weeks of treatment, spleen volume reduction ≥35% by MRI was achieved by 6/21 (29%) patients, and a ≥50% spleen length reduction by palpation at any time up to week 24 was obtained by 13/21 (62%) patients. At week 72, 8 of the 13 (62%) patients maintained the spleen response by palpation. No significant effect of treatment on esophageal varices or in splanchnic circulation was observed. MPN-related symptoms, evaluated by MPN-symptom assessment form (SAF) TSS questionnaire, improved significantly during the first 4 weeks and remained stable up to week 24. In conclusion, this trial shows that ruxolitinib is safe in patients with MPN-associated SVT, and effective in reducing spleen size and disease-related symptoms.
Assuntos
Janus Quinases/antagonistas & inibidores , Transtornos Mieloproliferativos/tratamento farmacológico , Pirazóis/efeitos adversos , Pirazóis/uso terapêutico , Circulação Esplâncnica/efeitos dos fármacos , Trombose Venosa/prevenção & controle , Adulto , Idoso , Esquema de Medicação , Feminino , Humanos , Janus Quinases/genética , Masculino , Pessoa de Meia-Idade , Transtornos Mieloproliferativos/sangue , Transtornos Mieloproliferativos/complicações , Nitrilas , Contagem de Plaquetas , Pirazóis/administração & dosagem , Pirimidinas , Esplenomegalia/prevenção & controle , Resultado do Tratamento , Trombose Venosa/sangue , Trombose Venosa/etiologiaAssuntos
Mieloma Múltiplo , Paraproteinemias , Humanos , Paraproteinemias/genética , Medicina de PrecisãoRESUMO
OBJECTIVES: Systemic immunological processes are profoundly shaped by the micro-environments where antigen recognition occurs. Identifying molecular signatures distinctive of such processes is pivotal to understand pathogenic immune responses and manipulate them for therapeutic purposes. Unfortunately, direct investigation of peripheral tissues, enriched in pathogenic T cells, is often impossible or imposingly invasive in humans. Conversely, blood is easily accessible, but pathogenic signatures are diluted systemically as a result of the strict compartmentalisation of immune responses. In this work, we aimed at defining immune mediators shared between the bloodstream and the synovial micro-environment, and relevant for disease activity in autoimmune arthritis. METHODS: CD4(+) T cells from blood and synovium of patients with juvenile idiopathic arthritis (JIA) were immunophenotyped by flow cytometry. The TCR repertoire of a circulating subset showing similarity with the synovium was analysed through next-generation sequencing of TCR ß-chain CDR3 to confirm enrichment in synovial clonotypes. Finally, clinical relevance was established by monitoring the size of this subset in the blood of patients with JIA and rheumatoid arthritis (RA). RESULTS: We identified a small subset of circulating CD4(+) T cells replicating the phenotypical signature of lymphocytes infiltrating the inflamed synovium. These circulating pathogenic-like lymphocytes (CPLs) were enriched in synovial clonotypes and they exhibited strong production of pro-inflammatory cytokines. Importantly, CPLs were expanded in patients with JIA, who did not respond to therapy, and also correlated with disease activity in patients with RA. CONCLUSIONS: CPLs provide an accessible reservoir of pathogenic cells recirculating into the bloodstream and correlating with disease activity, to be exploited for diagnostic and research purposes.
Assuntos
Artrite Juvenil/imunologia , Linfócitos T CD4-Positivos/imunologia , Genes Codificadores da Cadeia beta de Receptores de Linfócitos T/imunologia , Membrana Sinovial/imunologia , Artrite Juvenil/sangue , Artrite Juvenil/patologia , Artrite Reumatoide/sangue , Artrite Reumatoide/imunologia , Citometria de Fluxo , Humanos , Imunofenotipagem , Membrana Sinovial/patologiaRESUMO
Myeloproliferative neoplasm (MPN)-associated myelofibrosis is a clonal, neoplastic disorder of the hematopoietic stem cells, in which inflammation and immune dysregulation play an important role. Extracellular nicotinamide phosphoribosyltransferase (eNAMPT), also known as visfatin, is a cytokine implicated in a number of inflammatory and neoplastic diseases. Here plasma levels of eNAMPT in patients with MPN-associated myelofibrosis and their effects on disease phenotype and outcomes were examined. The concordance of eNAMPT levels with the marker of general inflammation high-sensitivity C-reactive protein (hs-CRP) was also studied. A total of 333 MPN-associated myelofibrosis patients (187 males and 146 females) and 31 age- and gender-matched normal-weight healthy subjects were enrolled in the study main body. Levels of eNAMPT and hs-CRP were simultaneously assayed in 209 MPN-associated myelofibrosis patients. Twenty-four polycythemia vera or essential thrombocythemia patients were used as controls. eNAMPT was over expressed in MPN-associated myelofibrosis, and eNAMPT expression was correlated with higher white blood cell count, higher hemoglobin, and higher platelet count, suggesting that eNAMPT is an indispensable permissive agent for myeloproliferation of MPN-associated myelofibrosis. The lack of correlation between eNAMPT and hs-CRP revealed that eNAMPT in MPN-associated myelofibrosis does not behave as a canonical inflammatory cytokine. In addition, higher levels of eNAMPT predicted longer time to blast transformation, and protected against progression toward thrombocytopenia and large splenomegaly. In conclusion, in MPN-associated myelofibrosis high levels of eNAMPT mark the myeloproliferative potential and, at variance with a high number of cancers, are protective against disease progression. Am. J. Hematol. 91:709-713, 2016. © 2016 Wiley Periodicals, Inc.
Assuntos
Citocinas/sangue , Progressão da Doença , Transtornos Mieloproliferativos/patologia , Nicotinamida Fosforribosiltransferase/sangue , Mielofibrose Primária/patologia , Proteína C-Reativa/análise , Estudos de Casos e Controles , Proliferação de Células , Feminino , Hemoglobinas/análise , Humanos , Contagem de Leucócitos , Masculino , Fenótipo , Contagem de Plaquetas , Policitemia Vera , Prognóstico , Trombocitemia EssencialRESUMO
Primary myelofibrosis (PMF) is characterized by megakaryocyte hyperplasia, dysplasia and death with progressive reticulin/collagen fibrosis in marrow and hematopoiesis in extramedullary sites. The mechanism of fibrosis was investigated by comparing TGF-ß1 signaling of marrow and spleen of patients with PMF and of non-diseased individuals. Expression of 39 (23 up-regulated and 16 down-regulated) and 38 (8 up-regulated and 30 down-regulated) TGF-ß1 signaling genes was altered in the marrow and spleen of PMF patients, respectively. Abnormalities included genes of TGF-ß1 signaling, cell cycling and abnormal in chronic myeloid leukemia (EVI1 and p21(CIP)) (both marrow and spleen) and Hedgehog (marrow only) and p53 (spleen only) signaling. Pathway analyses of these alterations predict an increased osteoblast differentiation, ineffective hematopoiesis and fibrosis driven by non-canonical TGF-ß1 signaling in marrow and increased proliferation and defective DNA repair in spleen. Since activation of non-canonical TGF-ß1 signaling is associated with fibrosis in autoimmune diseases, the hypothesis that fibrosis in PMF results from an autoimmune process triggered by dead megakaryocytes was tested by determining that PMF patients expressed plasma levels of mitochondrial DNA and anti-mitochondrial antibodies greater than normal controls. These data identify autoimmunity as a possible cause of marrow fibrosis in PMF.
Assuntos
Autoimunidade , Medula Óssea/patologia , Mielofibrose Primária/imunologia , Transdução de Sinais , Fator de Crescimento Transformador beta1/imunologia , Adulto , Animais , Medula Óssea/imunologia , Feminino , Humanos , Inflamação/imunologia , Inflamação/patologia , Masculino , Megacariócitos/imunologia , Megacariócitos/patologia , Camundongos , Mielofibrose Primária/patologia , Baço/imunologia , Baço/patologiaRESUMO
Primary myelofibrosis (PMF) is characterized by fibrosis, ineffective hematopoiesis in marrow, and hematopoiesis in extramedullary sites and is associated with abnormal megakaryocyte (MK) development and increased transforming growth factor (TGF)-ß1 release. To clarify the role of TGF-ß1 in the pathogenesis of this disease, the TGF-ß1 signaling pathway of marrow and spleen of the Gata1(low) mouse model of myelofibrosis (MF) was profiled and the consequences of inhibition of TGF-ß1 signaling on disease manifestations determined. The expression of 20 genes in marrow and 36 genes in spleen of Gata1(low) mice was altered. David-pathway analyses identified alterations of TGF-ß1, Hedgehog, and p53 signaling in marrow and spleen and of mammalian target of rapamycin (mTOR) in spleen only and predicted that these alterations would induce consequences consistent with the Gata1(low) phenotype (increased apoptosis and G1 arrest both in marrow and spleen and increased osteoblast differentiation and reduced ubiquitin-mediated proteolysis in marrow only). Inhibition of TGF-ß1 signaling normalized the expression of p53-related genes, restoring hematopoiesis and MK development and reducing fibrosis, neovascularization, and osteogenesis in marrow. It also normalized p53/mTOR/Hedgehog-related genes in spleen, reducing extramedullary hematopoiesis. These data identify altered expression signatures of TGF-ß1 signaling that may be responsible for MF in Gata1(low) mice and may represent additional targets for therapeutic intervention in PMF.
Assuntos
Modelos Animais de Doenças , Fator de Transcrição GATA1/fisiologia , Mielofibrose Primária/patologia , Transdução de Sinais , Fator de Crescimento Transformador beta1/metabolismo , Adulto , Animais , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Western Blotting , Medula Óssea/metabolismo , Medula Óssea/patologia , Estudos de Casos e Controles , Quimiocina CXCL12/genética , Quimiocina CXCL12/metabolismo , Citocinas/metabolismo , Citometria de Fluxo , Perfilação da Expressão Gênica , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Mielofibrose Primária/etiologia , Mielofibrose Primária/metabolismo , RNA Mensageiro/genética , RNA Interferente Pequeno/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Baço/metabolismo , Baço/patologia , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Fator de Crescimento Transformador beta1/antagonistas & inibidores , Fator de Crescimento Transformador beta1/genética , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
Increased microvessel density contributes to abnormal BM and spleen microenvironment in myelofibrosis (MF). Taking advantage of the JAK2V617F mutation as a marker of malignancy, in the present study, we investigated whether splenic endothelial cells (ECs) obtained from capillaries by laser microdissection or from fresh spleen tissue by cell culture or cell sorting harbored such mutation in patients bearing the mutation in their granulocytes and undergoing splenectomy for therapeutical reasons. To extend the analysis to the ECs of large vessels, endothelial tissue from the splenic vein was also studied. We found JAK2V617F(+) ECs in 12 of 18 patients also bearing the mutation in their granulocytes. In 3 patients, the mutation was found in at least 2 different EC samples obtained by laser microdissection, cell culture, or cell sorting. The mutation was detected in the splenic vein ECs of 1 of 6 patients investigated. In conclusion, we provide evidence that some ECs from the spleen and splenic veins of patients with MF bear the JAK2V617F mutation. We suggest that splenic ECs are involved in the process of malignant transformation in MF.
Assuntos
Células Endoteliais/patologia , Janus Quinase 2/genética , Mielofibrose Primária/genética , Baço/patologia , Idoso , Separação Celular , Hibridização Genômica Comparativa , Feminino , Citometria de Fluxo , Humanos , Hibridização in Situ Fluorescente , Microdissecção e Captura a Laser , Masculino , Pessoa de Meia-Idade , Mutação , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
The frequency of A3669G single nucleotide polymorphism (SNP) of human glucocorticoid receptor has been reported increased in polycythemia vera. We investigated the frequency of A3669G SNP and its impact on disease phenotype and progression in 499 patients with primary myelofibrosis (PMF). The distribution of the A3669G allele differed between PMF patients and 2 healthy control populations (odds ratio, 1.6 and 1.8). The variant allele at the homozygous state (G/G) was associated with higher white blood cell count, larger spleen index, and higher frequency of circulating CD34(+) cells at diagnosis. The latter association remained significant after correction for the JAK2V617F genotype. In patients JAK2V617F mutated, the G/G genotype was associated with shorter overall survival (77.6 months vs 298 months, P = .049) and blast transformation (BT)-free survival (76.7 months vs 261 months; P = .018). The latter association remained significant after correction for the known BT risk factors, such as age, sex, white blood cell count, percentage of blasts, IPSS prognostic score, and homozygosity for JAK2V617F (hazard ratio = 3.3; P = .006). In conclusion, the glucocorticoid receptor A3669G is a susceptibility allele for PMF: it contributes to confer the phenotype of excess myeloproliferation, and it cooperates with the JAK2V617F mutation in determining BT.
Assuntos
Predisposição Genética para Doença , Ativação Linfocitária/genética , Mutação/genética , Polimorfismo de Nucleotídeo Único/genética , Mielofibrose Primária/genética , Receptores de Glucocorticoides/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Criança , Estudos de Coortes , Feminino , Seguimentos , Humanos , Janus Quinase 2/genética , Masculino , Pessoa de Meia-Idade , Fenótipo , Mielofibrose Primária/mortalidade , Prognóstico , Taxa de Sobrevida , Adulto JovemRESUMO
We previously published that in patients with infantile hemangioma (IH) at the onset (T0) colony forming unit-fibroblasts (CFU-Fs) are present in in vitro cultures from PB. Herein, we characterize these CFU-Fs and investigate their potential role in IH pathogenesis, before and after propranolol therapy. The CFU-F phenotype (by flow cytometry), their differentiation capacity and ability to support angiogenesis (by in vitro cultures) and their gene expression (by RT-PCR) were evaluated. We found that CFU-Fs are actual circulating MSCs (cMSCs). In patients at T0, cMSCs had reduced adipogenic potential, supported the formation of tube-like structures in vitro and showed either inflammatory (IL1ß and ESM1) or angiogenic (F3) gene expression higher than that of cMSCs from CTRLs. In patients receiving one-year propranolol therapy, the cMSC differentiation in adipocytes improved, while their support in in vitro tube-like formation was lost; no difference was found between patient and CTRL cMSC gene expressions. In conclusion, in patients with IH at T0 the cMSC reduced adipogenic potential, their support in angiogenic activity and the inflammatory/angiogenic gene expression may fuel the tumor growth. One-year propranolol therapy modifies this picture, suggesting cMSCs as one of the drug targets.
Assuntos
Hemangioma , Células-Tronco Mesenquimais , Humanos , Propranolol/farmacologia , Propranolol/uso terapêutico , Propranolol/metabolismo , Transcriptoma , Células-Tronco Mesenquimais/metabolismo , Adipogenia/genética , Hemangioma/genética , Hemangioma/tratamento farmacológico , Hemangioma/metabolismoRESUMO
Primary myelofibrosis (PMF) is a myeloproliferative neoplasm characterized by a chronic inflammatory state that plays a relevant role in the disease pathogenesis (as proven by high levels of inflammatory cytokines with prognostic significance and by a persistent oxidative stress) and by extensive neoangiogenesis in bone marrow (BM) and spleen. Myeloid-derived suppressor cells (MDSCs) are immature cells that expand in patients with cancer, sepsis or chronic inflammation, favoring tumor onset and progression mainly through the decrease in immune surveillance and the promotion of neoangiogenesis. In this paper, we evaluated the presence of circulating MDSCs in PMF patients, the plasmatic factors involved in their mobilization/expansion and the correlations with laboratory, genetic and clinical parameters. The data indicated that MDSCs could have a relevant role in PMF as a new pathogenic mechanism contributing to explaining the phenotypic diversity observed during the clinical course of the disease, or a potential new target for personalized treatment.
Assuntos
Linfócitos T CD4-Positivos/patologia , Mielofibrose Primária/sangue , Linfócitos T Reguladores/patologia , Contagem de Linfócito CD4 , Linfócitos T CD4-Positivos/metabolismo , Estudos de Casos e Controles , Estudos Transversais , Feminino , Fatores de Transcrição Forkhead/metabolismo , Humanos , Subunidade alfa de Receptor de Interleucina-2/metabolismo , Subunidade alfa de Receptor de Interleucina-7/metabolismo , Masculino , Mielofibrose Primária/imunologia , Mielofibrose Primária/patologia , Linfócitos T Reguladores/metabolismoRESUMO
Megakaryocytes release platelets into the bloodstream by elongating proplatelets. In this study, we showed that human megakaryocytes constitutively release Transforming Growth Factor ß1 and express its receptors. Importantly, Transforming Growth Factor ß1 downstream signaling, through SMAD2/3 phosphorylation, was shown to be active in megakaryocytes extending proplatelets, indicating a type of autocrine stimulation on megakaryocyte development. Furthermore, inactivation of Transforming Growth Factor ß1 signaling, by the receptor inhibitors SB431542 and Stemolecule ALK5 inhibitor, determined a significant decrease in proplatelet formation. Recent studies indicated a crucial role of Transforming Growth Factor ß1 in the pathogenesis of primary myelofibrosis. We demonstrated that primary myelofibrosis-derived megakaryocytes expressed increased levels of bioactive Transforming Growth Factor ß1; however, higher levels of released Transforming Growth Factor ß1 did not lead to enhanced activation of downstream pathways. Overall, these data propose Transforming Growth Factor ß1 as a new element in the autocrine regulation of proplatelet formation in vitro. Despite the increase in Transforming Growth Factor ß1 this mechanism seems to be preserved in primary myelofibrosis.
Assuntos
Comunicação Autócrina , Megacariócitos/metabolismo , Mielofibrose Primária/genética , Fator de Crescimento Transformador beta1/genética , Benzamidas/farmacologia , Plaquetas/citologia , Plaquetas/metabolismo , Western Blotting , Células Cultivadas , Dioxóis/farmacologia , Expressão Gênica , Humanos , Megacariócitos/citologia , Fosforilação , Mielofibrose Primária/sangue , Mielofibrose Primária/metabolismo , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Receptor do Fator de Crescimento Transformador beta Tipo I , Receptor do Fator de Crescimento Transformador beta Tipo II , Receptores de Fatores de Crescimento Transformadores beta/antagonistas & inibidores , Receptores de Fatores de Crescimento Transformadores beta/genética , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Proteína Smad2/metabolismo , Proteína Smad3/metabolismo , Fator de Crescimento Transformador beta1/metabolismoRESUMO
BACKGROUND: Propranolol is currently considered the first-line therapy for problematic infantile hemangiomas (IH), the most common benign vascular neoplasm of infancy. OBJECTIVES: We present a retrospective observational study aimed at assessing the efficacy of propranolol in 44 IH patients. MATERIALS & METHODS: A nine-year retrospective review considering clinicodemographical and therapy-related variables was performed on medical records of infants treated for IH with oral propranolol. Each lesion was assessed through a numeric severity score based on size and colour both at baseline and after treatment conclusion (p <0.05 was considered statistically significant). RESULTS: Complete remission was achieved in 90.7% cases of IH with a general mean improvement in severity of 94.94%. No severe adverse effects were reported. Preterm patients showed a superior response compared to term infants, even though the difference was not significant (p=0.185). CONCLUSION: Propranolol showed high efficacy in terms of safety profile and cosmetic results. Prematurity and precocious therapy could be linked to a superior response.
Assuntos
Hemangioma Capilar , Neoplasias Vasculares , Humanos , Lactente , Recém-Nascido , Hemangioma Capilar/tratamento farmacológico , Propranolol/efeitos adversos , Centros de Atenção TerciáriaRESUMO
Different bodies of evidence support the existence of a common origin of hematopoietic and endothelial lineages; moreover, recent studies have indicated the presence of a hemogenic endothelium and a common hemato-endothelial precursor both in the embryo and in the cord blood. Conversely, to our knowledge, there is no evidence of such bipotential cells in human postnatal tissues or blood. In this study, we investigated the presence and phenotype of "transitional" cells in different tissues of patients with primary myelofibrosis (PMF). Using confocal microscopy and flow cytometry, we identified a rare cell population in the bone marrow and spleen of patients with PMF, which coexpresses the endothelial marker CD144 (vascular endothelial (VE)-cadherin), the pan-hematopoietic marker CD45, the early myeloid marker CD33, and CD34, a common endothelial and hematopoietic antigen.
Assuntos
Hemangioblastos , Mielofibrose Primária , Humanos , Medula Óssea , Baço , Antígenos CD34 , Biomarcadores , Células da Medula Óssea , Diferenciação CelularRESUMO
In primary myelofibrosis, extra-domain A fibronectin (EDA-FN), the result of alternative splicing of FN gene, sustains megakaryocyte proliferation and confers a pro-inflammatory phenotype to bone marrow cell niches. In this work we assessed the levels of circulating EDA-FN in plasma samples of 122 patients with primary myelofibrosis. Patients with a homozygous JAK2V617F genotype displayed the higher level of plasma EDA-FN. Increased EDA-FN levels were associated with anemia, elevated high-sensitivity C-reactive protein, bone marrow fibrosis and splanchnic vein thrombosis at diagnosis. While no correlation was observed with CD34+ hematopoietic stem cell mobilization, elevated blood level of EDA-FN at diagnosis was a predictor of large splenomegaly (over 10 cm from the left costal margin) outcome. Thus, EDA-FN expression in primary myelofibrosis may represent the first marker of disease progression, and a novel target to treat splenomegaly.
RESUMO
Two putative types of circulating endothelial progenitor cells have been recently identified in vitro: (1) endothelial colony-forming cell (ECFC) and (2) colony-forming unit-endothelial cell (CFU-EC). Only the former is now recognized to belong to endothelial lineage. We have used the ECFC and CFU-EC assays to readdress the issue of the clonal relation between endothelial progenitor cells and hematopoietic stem cells in patients with Philadelphia-positive and Philadelphia-negative chronic myeloproliferative disorders. Both ECFCs and CFU-ECs were cultured from peripheral blood mononuclear cells, and either BCR-ABL rearrangement or JAK2-V617F mutation were assessed in both types of endothelial colonies. We found that ECFCs lack the disease-specific markers, which are otherwise present in CFU-ECs, thus reinforcing the concept that the latter belongs to the hematopoietic lineage, and showing that in chronic myeloproliferative disorders the cell that gives rise to circulating ECFC has a distinct origin from the cell of the hematopoietic malignant clone.