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There are unresolved questions regarding the association between persistent leukocytosis and risk of thrombosis and disease evolution in polycythemia vera (PV), as much of the published literature on the topic does not appropriately use repeated-measures data or time-dependent modeling to answer these questions. To address this knowledge gap, we analyzed a retrospective database of 520 PV patients seen at 10 academic institutions across the United States. Taking hematologic laboratory data at â¼3-month intervals (or as available) for all patients for duration of follow-up, we used group-based trajectory modeling to identify latent clusters of patients who follow distinct trajectories with regard to their leukocyte, hematocrit, and platelet counts over time. We then tested the association between trajectory membership and hazard of 2 major outcomes: thrombosis and disease evolution to myelofibrosis, myelodysplastic syndrome, or acute myeloid leukemia. Controlling for relevant covariates, we found that persistently elevated leukocyte trajectories were not associated with the hazard of a thrombotic event (P = .4163), but were significantly associated with increased hazard of disease evolution in an ascending stepwise manner (overall P = .0002). In addition, we found that neither hematocrit nor platelet count was significantly associated with the hazard of thrombosis or disease evolution.
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Leucemia Mieloide Aguda/patologia , Leucocitose/fisiopatologia , Síndromes Mielodisplásicas/patologia , Policitemia Vera/complicações , Mielofibrose Primária/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Leucemia Mieloide Aguda/etiologia , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/etiologia , Policitemia Vera/patologia , Mielofibrose Primária/etiologia , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida , Trombose , Adulto JovemRESUMO
The International Paroxysmal Nocturnal Hemoglobinuria (PNH) Registry (NCT01374360) was initiated to optimize patient management by collecting data regarding disease burden, progression, and clinical outcomes. Herein, we report updated baseline demographics, clinical characteristics, disease burden data, and observed trends regarding clone size in the largest cohort of Registry patients. Patients with available data as of July 2017 were stratified by glycosylphosphatidylinositol (GPI)-deficient granulocyte clone size (< 10%, ≥ 10%-< 50%, and ≥ 50%). All patients were untreated with eculizumab at baseline, defined as date of eculizumab initiation or date of Registry enrollment (if never treated with eculizumab). Outcomes assessed in the current analysis included proportions of patients with high disease activity (HDA), history of major adverse vascular events (MAVEs; including thrombotic events [TEs]), bone marrow failure (BMF), red blood cell (RBC) transfusions, and PNH-related symptoms. A total of 4439 patients were included, of whom 2701 (60.8%) had available GPI-deficient granulocyte clone size data. Among these, median clone size was 31.8% (1002 had < 10%; 526 had ≥ 10%-< 50%; 1173 had ≥ 50%). There were high proportions of patients with HDA (51.6%), history of MAVEs (18.8%), BMF (62.6%), RBC transfusion (61.3%), and impaired renal function (42.8%). All measures except RBC transfusion history significantly correlated with GPI-deficient granulocyte clone size. A large proportion of patients with GPI-deficient granulocyte clone size < 10% had hemolysis (9.7%), MAVEs (10.2%), HDA (9.1%), and/or PNH-related symptoms. Although larger GPI-deficient granulocyte clone sizes were associated with higher disease burden, a substantial proportion of patients with smaller clone sizes had history of MAVEs/TEs.
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Hemoglobinúria Paroxística/diagnóstico , Hemoglobinúria Paroxística/epidemiologia , Adulto , Transtornos da Insuficiência da Medula Óssea/diagnóstico , Transtornos da Insuficiência da Medula Óssea/epidemiologia , Transtornos da Insuficiência da Medula Óssea/etiologia , Efeitos Psicossociais da Doença , Transfusão de Eritrócitos/estatística & dados numéricos , Feminino , Granulócitos/patologia , Hemoglobinúria Paroxística/patologia , Hemoglobinúria Paroxística/terapia , Humanos , Internacionalidade , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Sistema de Registros , Índice de Gravidade de Doença , Adulto JovemRESUMO
Acute erythroleukemia (AEL) is a rare disease typically associated with a poor prognosis. The median survival ranges between 3-9 months from initial diagnosis. Hypomethylating agents (HMAs) have been shown to prolong survival in patients with myelodysplastic syndromes (MDS) and AML, but there is limited data of their efficacy in AEL. We collected data from 210 AEL patients treated at 28 international sites. Overall survival (OS) and PFS were estimated using the Kaplan-Meier method and the log-rank test was used for subgroup comparisons. Survival between treatment groups was compared using the Cox proportional hazards regression model. Eighty-eight patients were treated with HMAs, 44 front line, and 122 with intensive chemotherapy (ICT). ICT led to a higher overall response rate (complete or partial) compared to first-line HMA (72% vs. 46.2%, respectively; p ≤ 0.001), but similar progression-free survival (8.0 vs. 9.4 months; p = 0.342). Overall survival was similar for ICT vs. HMAs (10.5 vs. 13.7 months; p = 0.564), but patients with high-risk cytogenetics treated with HMA first-line lived longer (7.5 for ICT vs. 13.3 months; p = 0.039). Our results support the therapeutic value of HMA in AEL.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Leucemia Eritroblástica Aguda/tratamento farmacológico , Leucemia Eritroblástica Aguda/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Azacitidina/administração & dosagem , Azacitidina/análogos & derivados , Biomarcadores , Medula Óssea/patologia , Análise Citogenética , Decitabina , Feminino , Humanos , Leucemia Eritroblástica Aguda/diagnóstico , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Análise de Sobrevida , Resultado do TratamentoRESUMO
Paroxysmal nocturnal hemoglobinuria (PNH) is a rare disorder caused by complement-mediated hemolysis and thrombosis through the alternative pathway. The most common symptom of PNH is fatigue due to chronic anemia, which can negatively impact quality of life (QoL) and affect overall well-being. The currently approved therapies for PNH significantly limit intravascular hemolysis (IVH) and reduce the risk of thrombosis; however, they are associated with an infusion schedule that can become burdensome, and not all patients experience complete disease control. Several new complement inhibitors are in development that address the need for convenient routes of administration and aim to provide better disease control. With the variety of new treatment options on the horizon, hematologic markers as well as QoL concerns, patient opinion, and lifestyle factors should be considered to choose the optimal PNH treatment for each specific patient.
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Hemoglobinúria Paroxística , Trombose , Humanos , Hemoglobinúria Paroxística/complicações , Hemoglobinúria Paroxística/diagnóstico , Hemoglobinúria Paroxística/tratamento farmacológico , Qualidade de Vida , Anticorpos Monoclonais Humanizados , Hemólise , Avaliação de Resultados da Assistência ao PacienteRESUMO
Myelofibrosis (MF)-associated anemia and transfusion dependency are associated with inferior quality of life and poor prognosis. JAK2 inhibitors and TGF-ß superfamily ligand traps are being explored as treatment options for MF-associated anemia. Here, we present the case of a 66-year-old man with heavily pretreated intermediate-2 (INT-2) risk primary MF who had an exceptional response to combination fedratinib and luspatercept therapy. He achieved transfusion independence and experienced a reduction in spleen size from 20 cm to 12 cm, with remarkable improvement in performance status. Compared with other JAK inhibitors, the mechanism of action of fedratinib may explain its milder effect on anemia. It is possible that the addition of luspatercept may result in an additive or synergistic effect of one or both medications. Although the exact biological pathways have not yet been elucidated, combination fedratinib and luspatercept nevertheless is a promising therapy for anemia in patients with transfusion-dependent INT-2 risk MF.
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Purpose: Most patients with paroxysmal nocturnal hemoglobinuria (PNH) treated with a complement protein 5 (C5) inhibitor achieve full control of terminal complement activity and intravascular hemolysis. The minority remains anemic and transfusion dependent despite this control. Etiology for ongoing anemia is multifactorial and includes bone marrow failure, breakthrough hemolysis, extravascular hemolysis (EVH) and nutritional deficiencies. Patients and Methods: To evaluate the potential etiologies of hemoglobin levels <10 g/dL despite receiving C5 inhibitor therapy, we performed a retrospective US chart review of adult patients with PNH and treated for at least 12 months with eculizumab (n=53), ravulizumab (n=32), or eculizumab followed by ravulizumab (n=15). Clinically evident EVH was defined as at least one transfusion, reticulocyte count ≥120×109/L and hemoglobin level ≤9.5 g/dL. Safety data were not collected. Mean treatment duration was 26.5±17.2 months. Results: Treatment with C5 inhibitors significantly improved hemoglobin, lactate dehydrogenase, and number of transfusions versus baseline. Among the patients with hemoglobin <10 g/dL during the last 6 months of treatment (n=38), one patient (eculizumab) had clinically evident EVH, and 10 patients had active concomitant bone marrow failure. Bone marrow failure was a major contributor to hemoglobin <10 g/dL and transfusion dependence; clinically evident EVH was uncommon. Conclusion: A range of hematologic causes need to be considered when evaluating anemia in the presence of treatment with a C5 inhibitor.
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Anagrelide (ANA) is a platelet-specific cytoreductive agent utilized in the guideline-directed management of high-risk essential thrombocythemia. In the context of polycythemia vera (PV), ANA is occasionally employed in clinical practice, although data has not consistently demonstrated a benefit to targeting a platelet goal as a therapeutic endpoint. The aim of the current study was to delineate the patterns of ANA use in PV, and to describe outcomes and toxicities. Within a multi-center cohort of 527 patients with PV, 48 received ANA (9 excluded for absent data). 27 (69.2%) had high-risk PV, 10 (25.6%) had prior thrombosis, and none had extreme thrombocytosis, acquired von Willebrand disease, and/or documented resistance to hydroxyurea. While ANA effectively lowered median platelet count, 43.5% of patients had an unresolved thrombocytosis at time of ANA discontinuation. Treatment-emergent adverse events-including headaches, cardiac palpitations and arrhythmias, nausea, vomiting and/or diarrhea-led to ANA discontinuation in 76.9% of patients. Further, three patients experienced arterial thromboses during a median duration of 27.5 months of ANA therapy. In conclusion, this study highlights ANA's restrictive tolerability profile which, compounded by the absence of clear advantage to strict platelet control in PV, suggests the use of ANA should be limited in this setting.
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Policitemia Vera , Trombocitemia Essencial , Trombocitose , Trombose , Procedimentos Cirúrgicos de Citorredução , Humanos , Policitemia Vera/tratamento farmacológico , Quinazolinas , Trombocitemia Essencial/tratamento farmacológico , Trombocitose/terapiaRESUMO
BACKGROUND: Myelodysplastic syndromes (MDS) comprise a heterogeneous group of hematologic malignancies, with an incidence rate of 3.4 cases per 100,000 in the United States. MDS affects patients predominantly over 60 years of age. As these syndromes are not well understood by many medical practitioner, patients with MDS may be underrecognized or underdiagnosed. The availability of new MDS treatment options further establishes the need to more closely assess gaps in clinical practice and underscores the necessity to develop educational activities to address those gaps. METHODS: A multidisciplinary panel was convened to examine current educational needs and gaps. A group consensus approach incorporating a modified nominal group technique was utilized to prioritize and review needs identified in the pre-meeting survey and to evaluate data provided by panelists prior to the meeting. RESULTS: The panel identified and prioritized seven educational areas of need: (1) MDS disease awareness, (2) diagnosis, (3) classification and risk stratification, (4) treatment issues, (5) referral to stem cell transplantation or new treatment protocols, (6) clinical monitoring and toxicity management, and (7) translation of new data into patient care. CONCLUSIONS: In-depth knowledge is critical to the timely diagnosis and optimal care of MDS patients. A number of key educational needs exist. Educational programs should be practical in orientation to integrate data into practice, and they should be tailored for the intended audience. In addition, an effective educational program must be easily applied by participants.
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Educação Médica Continuada , Síndromes Mielodisplásicas/diagnóstico , Síndromes Mielodisplásicas/terapia , Coleta de Dados , Conhecimentos, Atitudes e Prática em Saúde , HumanosRESUMO
Myelofibrosis (MF) is a life-threatening clonal stem cell malignancy characterized by progressive bone marrow fibrosis and ineffective hematopoiesis. The term "MF" encompasses primary myelofibrosis (PMF) as well as 2 other phenotypically similar malignancies: post-polycythemia vera (PV) MF (PPV-MF) and post-essential thrombocythemia (ET) MF (PET-MF). The World Health Organization classification system for myeloid malignancies recognizes PMF, PV, ET, and chronic myeloid leukemia (CML) as the "classic" myeloproliferative neoplasms (MPNs). Patients with low- or intermediate-1-risk disease have a median survival of 6-15 years, in contrast to those with intermediate-2- or high-risk disease, which is associated with a considerably worse prognosis. Following transformation into (secondary) acute myeloid leukemia (AML), the prognosis of MF is even worse, with a median survival of 3 months or less. Due to the heterogeneous nature of MF, the diagnosis and treatment of this malignancy can be challenging. At present, the only treatment that can be applied with curative intent is allogeneic stem cell transplantation (SCT), whereas no other specific therapies exist that are approved by the US Food and Drug Administration (FDA) for MF. Since most patients with MF appear not to be eligible for allogeneic SCT, patients are often treated by conventional "older" drugs such as androgens and hydroxyurea (HU; hydroxycarbamide), with the principal objective being palliation. Following the establishment of a causal role of a specific mutation in the Janus kinase type 2 (JAK2) gene, namely JAK2V617F, in the molecular pathogenesis of MPNs in 2005, many efforts have been directed towards the development of novel JAK2 (including JAK1/JAK2) inhibitors. Other investigative approaches include immunomodulatory agents, histone deacetylase inhibitors, hedgehog inhibitors, and others. Recently, the positive results of the first in class of the JAK1/JAK2 inhibitors, ruxolitinib (formerly INCB18242), from 2 large phase III studies were presented and are discussed herein.
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Mielofibrose Primária/diagnóstico , Mielofibrose Primária/terapia , HumanosRESUMO
May-Hegglin anomaly is the presentation of a qualitative platelet disorder characterised by large platelets, thrombocytopenia and granulocyte inclusions as a result of mutations in the MYH9 gene. Though often overlooked given its rarity, it should be considered in patients who present with epistaxis, bruising, menorrhagia and easy bleeding as it can be mistaken for other diagnoses resulting in unnecessary treatments and tests. Our case study reports one presentation of this anomaly and can help broaden awareness of the presentation of this type of patient.
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Perda Auditiva Neurossensorial , Trombocitopenia , Plaquetas , Feminino , Humanos , Mutação , Contagem de Plaquetas , Trombocitopenia/congênito , Trombocitopenia/diagnósticoRESUMO
BACKGROUND: Patient-reported outcome measures (PROs) used to measure symptoms of patients with paroxysmal nocturnal hemoglobinuria (PNH) in trials do not measure PNH symptoms comprehensively and do not assess daily fluctuations in symptoms. Following a literature review and consultation with a PNH expert, we drafted the PNH Symptom Questionnaire (PNH-SQ) and a patient-centric conceptual model of PNH symptoms and impacts. We then interviewed 15 patients with PNH to assess comprehensiveness of symptom capture from the patient perspective and to cognitively debrief the PNH-SQ. Patient interview data were also used to finalize the PNH conceptual model. RESULTS: Participants mentioned 27 signs or symptoms of PNH spontaneously or after being probed; 93% reported experiencing ≥ 1 PNH symptom. Concept saturation was reached for all PNH symptoms. Further, interviews confirmed the instrument captured the most common PNH symptoms, including fatigue (87%), abdominal pain (60%), and difficulty swallowing (47%), with fatigue ranked as the most bothersome symptom. The interviews demonstrated that participants understood the items of the PNH-SQ (90-100%); considered the symptoms relevant (> 50- > 90%); the recall period appropriate (> 80-100%); and the response options suitable (> 80-100%). Participants also suggested changes regarding item redundancy and relevance; this feedback was used to finalize the instrument. CONCLUSIONS: The finalized PNH-SQ assesses the presence and severity of 10 symptoms-abdominal pain, chest discomfort, difficulty sleeping, difficulty swallowing, difficulty thinking clearly, fatigue, headache, muscle weakness, pain in the legs or back, and shortness of breath-over 24 h. The PNH-SQ is a content-valid questionnaire suitable for assessing daily symptom presence and severity in PNH clinical trials.
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Ruxolitinib is approved for the treatment of patients with polycythemia vera (PV) who are intolerant or resistant to hydroxyurea. While ruxolitinib discontinuation in myelofibrosis is associated with dismal outcomes, the analogous experience in PV has not been reported. Using a large, multi-institutional database of PV patients, we identified 93 patients with PV who were treated with ruxolitinib, of whom 22 discontinued therapy. Adverse events were the primary reason for discontinuation. After a median follow-up of 18.2 months following ruxolitinib discontinuation, no patients experienced a thrombotic event. One patient died 20.8 months after discontinuation. As compared with the 71 patients who were still receiving treatment with ruxolitinib at last follow up, patients who discontinued ruxolitinib were older at time of treatment initiation (67.5 versus 64.8 years, p = 0.0058), but had similar patient and disease characteristics. After discontinuation, only 4 patients (18 %) received subsequent cytoreductive therapy, including hydroxyurea in one patient and pegylated interferon α-2a in three patients. In stark contrast to the experience in myelofibrosis, discontinuation of ruxolitinib in PV was associated with generally favorable outcomes. However, there is a lack of available salvage therapies, highlighting the need for further therapeutic development in PV.
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Nitrilas/uso terapêutico , Policitemia Vera/tratamento farmacológico , Pirazóis/uso terapêutico , Pirimidinas/uso terapêutico , Terapia de Salvação , Suspensão de Tratamento/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Policitemia Vera/patologia , Prognóstico , Estudos Retrospectivos , Taxa de SobrevidaRESUMO
Patients with paroxysmal nocturnal hemoglobinuria (PNH) often experience a lengthy path to diagnosis. Fewer than 40% of patients with PNH receive a diagnosis within 12 months of symptom onset, and 24% of all PNH diagnoses can take 5 years or longer. Diagnostic delay is a source of distress and can affect emotional well-being for patients with PNH. In PNH disease management, patients and care providers focus on risk of organ failure and mortality related to disease progression; nonetheless, patients' health-related quality of life (HRQOL) is largely affected by extensive treatment requirements and nonfatal complications of disease, such as fatigue. In particular, thrombosis is associated with significant impairments in physical and social functioning and global health status and significant fatigue. Among patients with anemia who are transfusion dependent, the burden of transfusion is considerable. Transfusion dependence has a negative effect on HRQOL; is associated with risks and complications, including iron overload; and results in lost productivity due to travel times to and time spent at infusion centers. DISCLOSURES: This research was developed under a research contract between RTI Health Solutions and Apellis Pharmaceuticals and was funded by Apellis Pharmaceuticals. Bektas, Copley-Merriman, and Khan are employees of RTI Health Solutions. Sarda is an employee of Apellis Pharmaceuticals. Shammo consults for Apellis Pharmaceuticals.
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Hemoglobinúria Paroxística/psicologia , Transfusão de Sangue/métodos , Efeitos Psicossociais da Doença , Diagnóstico Tardio , Progressão da Doença , Hemoglobinúria Paroxística/diagnóstico , Hemoglobinúria Paroxística/terapia , Humanos , Qualidade de VidaRESUMO
The complement system is part of the innate immune response system, which comprises more than 50 distinct plasma and serum proteins that interact to opsonize pathogens (i.e., mark pathogens for destruction) and induce inflammatory responses to fight infection. The role of the complement system is 2-fold: immune surveillance and host defense. Paroxysmal nocturnal hemoglobinuria (PNH) is a rare, chronic, acquired, hematologic disease caused by somatic mutations in the gene PIGA in the hematopoietic stem cells. These stem cells produce abnormal clone blood cells that lack the complement regulatory proteins CD55 and CD59, causing the body to recognize these otherwise healthy red blood cells as damaged. The complement system destroys cells without these protective proteins, resulting in general hemolysis. PNH is characterized by fatigue; hemolytic anemia that can be severe and debilitating; increased lactic dehydrogenase level, reticulocyte count, and bilirubin level; propensity for thrombotic events; and renal dysfunction. Epidemiologic data, while sparse, suggest that an estimated 5,000-6,000 individuals in the United States are affected by PNH. If left untreated, PNH has a 10-year mortality rate of 29%, although the natural history of this disease has been recently altered by the introduction of complement inhibitors for the treatment of PNH. DISCLOSURES: This research was developed under a research contract between RTI Health Solutions and Apellis Pharmaceuticals and was funded by Apellis Pharmaceuticals. Bektas, Copley-Merriman, and Khan are employees of RTI Health Solutions. Sarda is an employee of Apellis Pharmaceuticals. Shammo consults for Apellis Pharmaceuticals.
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Proteínas do Sistema Complemento , Hemoglobinúria Paroxística/fisiopatologia , Animais , Hemoglobinúria Paroxística/terapia , Hemólise , Humanos , Imunidade InataRESUMO
The current standard of care for paroxysmal nocturnal hemoglobinuria (PNH) are the C5 inhibitors eculizumab and ravulizumab, both monoclonal antibodies designed to target the complement protein C5, thereby preventing its cleavage and the formation of the terminal attack complex. C5 inhibitors have yielded substantial improvements in the treatment of PNH and changed the mortality and morbidity, as well as health-related quality of life of patients with the disease. These treatments target underlying intravascular hemolysis; however, they do not address extravascular hemolysis, resulting in incomplete response and remaining symptoms in some patients. Therefore, despite treatment with a C5 inhibitor, some patients still experience anemia with associated fatigue, transfusion needs, and impaired health-related quality of life. DISCLOSURES: This research was developed under a research contract between RTI Health Solutions and Apellis Pharmaceuticals and was funded by Apellis Pharmaceuticals. Bektas, Copley-Merriman, and Khan are employees of RTI Health Solutions. Sarda is an employee of Apellis Pharmaceuticals. Shammo consults for Apellis Pharmaceuticals.
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Hemoglobinúria Paroxística/tratamento farmacológico , Anemia/etiologia , Anticorpos Monoclonais Humanizados , Complemento C5/antagonistas & inibidores , Necessidades e Demandas de Serviços de Saúde , Hemoglobinúria Paroxística/complicações , Hemoglobinúria Paroxística/mortalidade , Hemólise , Humanos , Qualidade de VidaRESUMO
INTRODUCTION: Patients with myelodysplastic syndromes (MDS) are at increased risk of iron overload due to ineffective erythropoiesis and chronic transfusion therapy. The clinical consequences of iron overload include cardiac and/or hepatic failure, endocrinopathies, and infection risk. Areas covered: Iron chelation therapy (ICT) can help remove excess iron and ultimately reduce the clinical consequences of iron overload. The authors reviewed recent (last five years) English-language articles from PubMed on the topic of iron overload-related complications and the use of ICT (primarily deferasirox) to improve outcomes in patients with MDS. Expert commentary: While a benefit of ICT has been more firmly established in other transfusion-dependent conditions, such as thalassemia, its role in reducing iron overload in MDS remains controversial due to the lack of prospective controlled data demonstrating a survival benefit. Orally administered chelation agents (e.g. deferasirox) are now available, and observational and/or retrospective data support a survival benefit of using ICT in MDS. The placebo-controlled TELESTO trial (NCT00940602) is currently examining the use of deferasirox in MDS patients with iron overload, and is evaluating specifically whether use of ICT to alleviate iron overload can also reduce iron overload-related complications in MDS and improve survival.
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Transfusão de Sangue , Deferasirox/uso terapêutico , Quelantes de Ferro/uso terapêutico , Sobrecarga de Ferro , Síndromes Mielodisplásicas , Reação Transfusional , Intervalo Livre de Doença , Humanos , Sobrecarga de Ferro/sangue , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/etiologia , Sobrecarga de Ferro/mortalidade , Síndromes Mielodisplásicas/sangue , Síndromes Mielodisplásicas/mortalidade , Síndromes Mielodisplásicas/terapia , Ensaios Clínicos Controlados Aleatórios como Assunto , Taxa de Sobrevida , Reação Transfusional/sangue , Reação Transfusional/tratamento farmacológico , Reação Transfusional/mortalidadeRESUMO
In the originally published version of this Article, the GAPDH loading control blot in Fig. 1a was inadvertently replaced with a duplicate of the DNMT2 blot in the same panel during assembly of the figure. This has now been corrected in both the PDF and HTML versions of the Article.
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The roles of RNA 5-methylcytosine (RNA:m5C) and RNA:m5C methyltransferases (RCMTs) in lineage-associated chromatin organization and drug response/resistance are unclear. Here we demonstrate that the RCMTs, namely NSUN3 and DNMT2, directly bind hnRNPK, a conserved RNA-binding protein. hnRNPK interacts with the lineage-determining transcription factors (TFs), GATA1 and SPI1/PU.1, and with CDK9/P-TEFb to recruit RNA-polymerase-II at nascent RNA, leading to formation of 5-Azacitidine (5-AZA)-sensitive chromatin structure. In contrast, NSUN1 binds BRD4 and RNA-polymerase-II to form an active chromatin structure that is insensitive to 5-AZA, but hypersensitive to the BRD4 inhibitor JQ1 and to the downregulation of NSUN1 by siRNAs. Both 5-AZA-resistant leukaemia cell lines and clinically 5-AZA-resistant myelodysplastic syndrome and acute myeloid leukaemia specimens have a significant increase in RNA:m5C and NSUN1-/BRD4-associated active chromatin. This study reveals novel RNA:m5C/RCMT-mediated chromatin structures that modulate 5-AZA response/resistance in leukaemia cells, and hence provides a new insight into treatment of leukaemia.
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Antineoplásicos/farmacologia , Azacitidina/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Leucêmica da Expressão Gênica , Leucemia Mieloide Aguda/genética , Síndromes Mielodisplásicas/genética , RNA Neoplásico/genética , Medula Óssea/efeitos dos fármacos , Medula Óssea/metabolismo , Medula Óssea/patologia , Proteínas de Ciclo Celular , Linhagem Celular Tumoral , Cromatina/química , Cromatina/efeitos dos fármacos , Cromatina/metabolismo , Montagem e Desmontagem da Cromatina , Quinase 9 Dependente de Ciclina/genética , Quinase 9 Dependente de Ciclina/metabolismo , Citosina/metabolismo , DNA (Citosina-5-)-Metiltransferases/genética , DNA (Citosina-5-)-Metiltransferases/metabolismo , Fator de Transcrição GATA1/genética , Fator de Transcrição GATA1/metabolismo , Ribonucleoproteínas Nucleares Heterogêneas Grupo K/genética , Ribonucleoproteínas Nucleares Heterogêneas Grupo K/metabolismo , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , Metilação , Metiltransferases/genética , Metiltransferases/metabolismo , Síndromes Mielodisplásicas/tratamento farmacológico , Síndromes Mielodisplásicas/metabolismo , Síndromes Mielodisplásicas/patologia , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Ligação Proteica , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , RNA Neoplásico/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Transdução de Sinais , Transativadores/genética , Transativadores/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismoRESUMO
The aim of this open-label, single-center, phase 2 study was to assess the efficacy and safety of dose-dense CHOP-R-14 followed by 90Y-ibritumomab radioimmunotherapy (RIT) in patients with previously untreated diffuse large B-cell lymphoma (DLBCL). A total of 20 patients, the majority presenting with high-risk characteristics, were enrolled to receive dose-dense cyclophosphamide, doxorubicin, vincristine, prednisone and rituximab every 14 days (CHOP-R-14), followed by 90Y-ibritumomab tiuxetan consolidation. Sixteen patients completed RIT consolidation (rituximab 250 mg/m2 on day 1 and day 7, 8, or 9, followed by a single injection of 90Y-ibritumomab). Complete response (CR) rates of 75 and 95% were observed after treatment with CHOP-R-14 and RIT, respectively; 4 of the 5 patients who achieved a partial response after CHOP-R-14 converted to CR following treatment with RIT. With a median follow-up of 89.7 months, the progression-free and overall survival rates for the cohort were 75 and 85%, respectively. Hematological adverse events were common following CHOP-R-14 and RIT, but they were manageable with treatment interruption. Therefore, this regimen achieved promising survival outcomes in high-risk DLBCL on long term follow-up, with manageable toxicity.