Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 26
Filtrar
1.
Blood ; 140(26): 2805-2817, 2022 12 29.
Artigo em Inglês | MEDLINE | ID: mdl-36283106

RESUMO

Myelofibrosis (MF) is a disease associated with high unmet medical needs because allogeneic stem cell transplantation is not an option for most patients, and JAK inhibitors are generally effective for only 2 to 3 years and do not delay disease progression. MF is characterized by dysplastic megakaryocytic hyperplasia and progression to fulminant disease, which is associated with progressively increasing marrow fibrosis. Despite evidence that the inflammatory milieu in MF contributes to disease progression, the specific factors that promote megakaryocyte growth are poorly understood. Here, we analyzed changes in the cytokine profiles of MF mouse models before and after the development of fibrosis, coupled with the analysis of bone marrow populations using single-cell RNA sequencing. We found high interleukin 13 (IL-13) levels in the bone marrow of MF mice. IL-13 promoted the growth of mutant megakaryocytes and induced surface expression of transforming growth factor ß and collagen biosynthesis. Similarly, analysis of samples from patients with MF revealed elevated levels of IL-13 in the plasma and increased IL-13 receptor expression in marrow megakaryocytes. In vivo, IL-13 overexpression promoted disease progression, whereas reducing IL-13/IL-4 signaling reduced several features of the disease, including fibrosis. Finally, we observed an increase in the number of marrow T cells and mast cells, which are known sources of IL-13. Together, our data demonstrate that IL-13 is involved in disease progression in MF and that inhibition of the IL-13/IL-4 signaling pathway might serve as a novel therapeutic target to treat MF.


Assuntos
Transtornos Mieloproliferativos , Neoplasias , Mielofibrose Primária , Camundongos , Animais , Interleucina-13/uso terapêutico , Interleucina-4 , Neoplasias/complicações , Transtornos Mieloproliferativos/complicações , Mielofibrose Primária/genética , Transdução de Sinais/genética , Fibrose , Progressão da Doença
2.
Ther Adv Hematol ; 13: 20406207221084487, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35371428

RESUMO

Background: Myelofibrosis (MF) is a blood cancer associated with splenomegaly, blood count abnormalities, reduced life expectancy and high prevalence of disease-associated symptoms. Current treatment options for MF are diverse, with limited data on management strategies in real-world practice in the United Kingdom. Methods: The REALISM UK study was a multi-center, retrospective, non-interventional study, which documented the early management of patients with MF. The primary endpoint was the time from diagnosis to active treatment. Discussion: Two hundred patients were included (63% [n = 126/200] with primary MF; 37% [n = 74/200] with secondary MF). Symptoms and prognostic scores at diagnosis were poorly documented, with infrequent use of patient reported outcome measures. 'Watch and wait' was the first management strategy for 53.5% (n = 107/200) of patients, while the most commonly used active treatments were hydroxycarbamide and ruxolitinib. Only 5% of patients proceeded to allogeneic transplant. The median (IQR) time to first active treatment was 46 days (0-350); patients with higher risk disease were prescribed active treatment sooner. Conclusion: These results provide insight into real-world clinical practice for patients with MF in the United Kingdom. Despite the known high prevalence of disease-associated symptoms in MF, symptoms were poorly documented. Most patients were initially observed or received hydroxycarbamide, and ruxolitinib was used as first-line management strategy in only a minority of patients. Plain Language Summary: Background: Myelofibrosis is a rare blood cancer associated with symptoms that can seriously affect a patient's daily life, such as enlarged spleen and decreased white and red blood cells. Although several treatments are available for patients with myelofibrosis, it is not clear which ones clinicians use most frequently.Methods: We aimed to review which treatments are usually given to patients with myelofibrosis in the UK, by collecting information from the medical records of 200 patients with myelofibrosis treated in different centres across the UK.Results: The results showed that the symptoms patients experienced were not always written down in the medical records. Similarly, clinical scores based on patient characteristics (which clinicians use to try to predict if a patient will respond to treatment well or not) were also missing from the medical records. Clinicians also rarely asked patients to complete questionnaires that try to measure the impact of myelofibrosis and its treatment on their health. The most common approach for patients with myelofibrosis in the UK was 'watch and wait', which over half of patients received. The most common drugs used for treatment were hydroxycarbamide and ruxolitinib; only a very small proportion of patients received a bone marrow transplant. On average, patients waited for 46 days before receiving a treatment, although patients considered to have a more aggressive type of disease received treatment sooner.Conclusion: The results of this study suggest that medical records can be missing key information, which is needed to decide which is the best way to treat a patient with myelofibrosis. They also suggest that clinicians in the UK prefer observation to treatment for a large number of patients with myelofibrosis. This could mean that the approach used for many patients with myelofibrosis does not help them to control symptoms that have an impact on their daily lives.

3.
BMJ Case Rep ; 14(5)2021 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-34016631

RESUMO

We present a 47-year-old, South-African origin, woman with a background of stable monoclonal gammopathy of unknown significance (MGUS) who attended A&E with a history of coryzal symptoms associated with persistent fever, lymphadenopathy and a new onset of rash, not responding to antibiotics and paracetamol. A trial of high-dose steroids resolved symptoms. Bone marrow biopsy confirmed a progression of MGUS into multiple myeloma and her axillary lymph node biopsy analysis supported a diagnosis of Kikuchi-Fujimoto disease (KFD). This is an unusual presentation where KFD has been noted alongside MGUS progression to multiple myeloma. Haematology follow-up is underway.


Assuntos
Linfadenite Histiocítica Necrosante , Linfadenopatia , Gamopatia Monoclonal de Significância Indeterminada , Mieloma Múltiplo , Biópsia , Feminino , Linfadenite Histiocítica Necrosante/complicações , Linfadenite Histiocítica Necrosante/diagnóstico , Linfadenite Histiocítica Necrosante/tratamento farmacológico , Humanos , Pessoa de Meia-Idade , Mieloma Múltiplo/complicações , Mieloma Múltiplo/diagnóstico , Mieloma Múltiplo/tratamento farmacológico
4.
Am J Blood Res ; 11(1): 84-92, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33796394

RESUMO

Foetal spleen is described as a transient focus of haematopoiesis between the 3rd and 5th month of gestation: this function is however entirely replaced by the bone marrow before the end of pregnancy. This study identifies haematopoiesis in foetal spleen by exploring changes of echogenicity during its development throughout gestation. Two intervals of pregnancy were studied: Mid-Pregnancy (Mid-P, 19-23 weeks) and End-Pregnancy (End-P, 37-41 weeks). The foetal spleen was investigated in 80 pregnant women (41 vs 39). Due to quality criteria the comparison was made between 60 images (30 Mid-P vs 30 End-P). The acquisition of splenic parenchyma was followed by clustering segmentation. We identified two new parameters resulted from the clustering segmentation: Dark Ratio (DR) and Light Ratio (LR). These are related to splenic echogenicity expressing the percentage of dark and light signal in the clustered image, influenced by blood cellularity. The mean of DR value was different among the 2 groups (0.0631 vs 0.0483, P = 0.014), while LR did not show any significant differences. We conclude that DR may represent a reliable radiomic parameter in the determination of extramedullary haematopoiesis in the spleen.

5.
J Thromb Haemost ; 17(6): 896-900, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30889303

RESUMO

Essentials The BCR-ABL negative myeloproliferative neoplasms are subjected to unknown phenotypic modifiers. GATA-1 is upregulated in ET patients, regardless of treatment regimen or mutational status. Myelofibrosis (MF) megakaryocytes displayed decreased GATA-1 staining. GATA-1 may have utility as a diagnostic marker in ET and in its differential diagnosis from MF. ABSTRACT: Background The BCR-ABL-negative myeloproliferative neoplasms, i.e., polycythemia vera, essential thrombocythemia (ET), and myelofibrosis (MF), are characterized by mutations in JAK2, CALR, or MPL. However, an as yet unknown factor drives the precise disease phenotype. The hematopoietic transcription factor GATA-1 and its downstream targets NFE2 and FLI1 are responsible for determining erythroid and megakaryocyte lineages during hematopoietic stem cell differentiation. Previous studies have demonstrated a low level of GATA-1 expression in megakaryocytes from patients with MF. Objectives and methods The expression of GATA-1, NFE2 and FLI1 was studied for changes in the peripheral blood (PB) of ET patients. Peripheral blood samples were obtained from 36 ET patients, 14 MF patients, and seven healthy control donors. Total RNA from PB mononuclear cells (PBMCs) was extracted, and quantitative polymerase chain reaction was used to determine relative changes in gene expression. Protein levels of GATA-1 were also determined in bone marrow sections from ET and MF patients. Results GATA-1 mRNA was upregulated in ET patients, regardless of treatment regimen or mutational status. FLI1 expression was significantly downregulated, whereas NFE2 expression was unaffected by changes in GATA-1 mRNA levels. Megakaryocytes from ET patients showed increased protein levels of GATA-1 as compared with those from MF patients. Conclusions Our results confirmed, in PB, our previous data demonstrating elevated levels of GATA-1 mRNA in total bone marrow of ET patients. GATA-1 mRNA levels are independent of cytoreductive therapies, and may have utility as a diagnostic marker in ET and in its differential diagnosis from MF.


Assuntos
Fator de Transcrição GATA1/metabolismo , Mielofibrose Primária/diagnóstico , Trombocitemia Essencial/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/metabolismo , Medula Óssea/metabolismo , Estudos de Casos e Controles , Diagnóstico Diferencial , Feminino , Fator de Transcrição GATA1/genética , Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Subunidade p45 do Fator de Transcrição NF-E2/genética , Mielofibrose Primária/genética , Mielofibrose Primária/metabolismo , Proteína Proto-Oncogênica c-fli-1/genética , RNA Mensageiro/sangue , RNA Mensageiro/genética , Trombocitemia Essencial/genética , Trombocitemia Essencial/metabolismo
7.
Br J Haematol ; 176(1): 76-85, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27858987

RESUMO

The randomized, double-blind, double-dummy, phase 3b RELIEF trial evaluated polycythaemia vera (PV)-related symptoms in patients who were well controlled with a stable dose of hydroxycarbamide (also termed hydroxyurea) but reported PV-related symptoms. Patients were randomized 1:1 to ruxolitinib 10 mg BID (n = 54) or hydroxycarbamide (prerandomization dose/schedule; n = 56); crossover to ruxolitinib was permitted after Week 16. The primary endpoint, ≥50% improvement from baseline in myeloproliferative neoplasm -symptom assessment form total symptom score cytokine symptom cluster (TSS-C; sum of tiredness, itching, muscle aches, night sweats, and sweats while awake) at Week 16, was achieved by 43·4% vs. 29·6% of ruxolitinib- and hydroxycarbamide-treated patients, respectively (odds ratio, 1·82; 95% confidence interval, 0·82-4·04; P = 0·139). The primary endpoint was achieved by 34% of a subgroup who maintained their hydroxycarbamide dose from baseline to Weeks 13-16. In a post hoc analysis, the primary endpoint was achieved by more patients with stable screening-to-baseline TSS-C scores (ratio ≤ 2) receiving ruxolitinib than hydroxycarbamide (47·4% vs. 25·0%; P = 0·0346). Ruxolitinib treatment after unblinding was associated with continued symptom score improvements. Adverse events were primarily grades 1/2 with no unexpected safety signals. Ruxolitinib was associated with a nonsignificant trend towards improved PV-related symptoms versus hydroxycarbamide, although an unexpectedly large proportion of patients who maintained their hydroxycarbamide dose reported symptom improvement.


Assuntos
Substituição de Medicamentos , Hidroxiureia/uso terapêutico , Policitemia Vera/tratamento farmacológico , Pirazóis/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Cross-Over , Método Duplo-Cego , Fadiga , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nitrilas , Pirimidinas , Qualidade de Vida , Resultado do Tratamento , Adulto Jovem
8.
Case Rep Oncol ; 6(2): 285-8, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23898270

RESUMO

INTRODUCTION: Over the past year, 3 agents have been approved for the treatment of melanoma by the Food and Drug Administration. These include pegylated interferon α-2b for stage III melanoma, vemurafenib for unresectable or metastatic melanoma with BRAF V600E mutation, and ipilimumab for unresectable or metastatic melanoma. CASE PRESENTATION: We present here the case of a 65-year-old Caucasian male diagnosed with advanced melanoma in April 2011 and treated with ipilimumab (Yervoy(®)), a monoclonal antibody targeting cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4), as second-line treatment after progression with dacarbazine, for (wild-type BRAF) metastatic melanoma. The patient was referred to us for several painful lumps on his right arm. A biopsy of one of them revealed melanoma. CT and PET scans did not show any other lesions or a primary site. The patient was started on first-line chemotherapy with dacarbazine 850 mg/m(2) on day 1, every 3 weeks. After 3 cycles, the patient showed disease progression with an increase in size of the skin metastasis. Second-line treatment was started with ipilimumab 3 mg/kg on day 1, every 3 weeks. At the end of the treatment, after 4 cycles, we documented a complete clinical response with total resolution of the skin metastasis. At the time of writing this paper, our patient had finished his treatment more than 9 months earlier and is still in complete remission. CONCLUSION: This is a paradigmatic case where, despite extensive metastatic disease, treatment with ipilimumab has confirmed its efficacy. It is still an open question why only a minority of patients have such a remarkable response, and further trials are warranted to address this important question.

9.
Acta Cytol ; 57(4): 337-40, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23860494

RESUMO

OBJECTIVE: Recently, fine needle cytology (FNC) of the thyroid has been combined with biomolecular analysis. In particular, there has been detailed study of the V600E-BRAF mutation. The aim of our study is to demonstrate that with a single thyroid sample it is possible to obtain enough cellular material for both cytological diagnosis and a V600E-BRAF molecular test. STUDY DESIGN: FNC was carried out under ultrasound guidance aided by an echographist and cytopathologist. We acquired one biopsy for each nodule with a 23-gauge needle without suction. The preparations were smeared by the pathologist onto one glass slide, air dried and stained with Diff-Quick. Cell adequacy was evaluated for each patient. The needle was washed by aspirating 2 ml of physiologic solution which was collected into a tube. The material was collected for molecular testing. RESULTS: The following cytological diagnoses were made: not neoplastic, Tir2 (n = 227); indeterminate, Tir3 (n = 15); suspicious, Tir4 (n = 4), and malignancy, Tir5 (n = 12). The V600E-BRAF mutation was found in 0 of 227 Tir2 specimens, 2 of 15 (13.3%) Tir3 specimens, 2 of 4 (50%) Tir4 specimens and 9 of 12 (75%) Tir5 specimens. CONCLUSIONS: Our data showed that, in a routine clinical setting, FNC specimens can be handled properly to provide both morphological and molecular information. In fact, our tests show that with a single specimen it is possible to set up a slide for the cytological diagnosis and to obtain enough residual cellular material for DNA extraction (>70 ng) and for the identification of the V600E-BRAF mutation.


Assuntos
Biópsia por Agulha Fina , Citodiagnóstico/métodos , Proteínas Proto-Oncogênicas B-raf/genética , Nódulo da Glândula Tireoide/genética , Nódulo da Glândula Tireoide/patologia , Humanos , Reação em Cadeia da Polimerase , Proteínas Proto-Oncogênicas B-raf/análise , Sensibilidade e Especificidade
10.
Case Rep Hematol ; 2013: 379898, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23533847

RESUMO

The allogeneic bone marrow transplantation usually preceded by induction chemotherapy, in fit patients, represents the gold standard in the acute myeloid leukaemia. In the last years, many trials have been set up with the view of improving the number of remissions during the induction by adding new drugs. Several early or late side effects have been described in the literature. We herein present a patient with acute myeloid leukaemia patient who, after chemotherapy, developed ascites that turned out to be abdominal sarcoidosis.

11.
Tumori ; 98(3): 76e-78e, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22825523

RESUMO

AIM AND BACKGROUND: Small cell carcinoma of the prostate (SCCP) is a relatively rare entity, an aggressive tumor with a tendency to metastasize early. There is no standard chemotherapy regimen for SCCP. We report the case of a 67-year-old man with an initial diagnosis of prostate adenocarcinoma with bone metastases who subsequently developed a small cell carcinoma of the prostate with liver metastases. METHODS AND STUDY DESIGN: A review of this case and of the current literature was done with a view to highlighting the ideal approach to such an unusual tumor. RESULTS AND CONCLUSION: The patient was treated with carboplatin and etoposide and after 3 cycles achieved a good response. Unfortunately he developed massive pulmonary embolism which impeded the continuation of treatment and caused his death. By reviewing the literature we found there is no standard of care and new targeted therapies have failed to prove any benefit so far. It is mandatory to persevere in planning trials and exploring new drugs to improve the outcome of patients with SCCP. It might also be worth creating a register for SCCP where data can be collected to coordinate the management of these patients and to establish better connections among cancer centers.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais/sangue , Carcinoma de Células Pequenas , Neoplasias Hepáticas , Antígeno Prostático Específico/sangue , Neoplasias da Próstata , Embolia Pulmonar/diagnóstico , Idoso , Antineoplásicos Hormonais/administração & dosagem , Carboplatina/administração & dosagem , Carcinoma de Células Pequenas/sangue , Carcinoma de Células Pequenas/diagnóstico , Carcinoma de Células Pequenas/tratamento farmacológico , Carcinoma de Células Pequenas/secundário , Etoposídeo/administração & dosagem , Evolução Fatal , Humanos , Leuprolida/administração & dosagem , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/secundário , Masculino , Neoplasias da Próstata/sangue , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia
12.
Blood ; 116(26): 6023-6, 2010 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-20861460

RESUMO

Recently, Dawson et al identified a previously unrecognized nuclear role of JAK2 in the phosphorylation of histone H3 in hematopoietic cell lines. We searched nuclear JAK2 in total bone marrow (BM) cells and in 4 sorted BM cell populations (CD34(+), CD15(+), CD41(+), and CD71(+)) of 10 myeloproliferative neoplasia (MPN) patients with JAK2V617F mutation and 5 patients with wild-type JAK2 MPN. Confocal immunofluorescent images and Western blot analyses of nuclear and cytoplasmic fractions found nuclear JAK2 in CD34(+) cells of 10 of 10 JAK2-mutated patients but not in patients with wild-type JAK2. JAK2 was predominantly in the cytoplasmic fraction of differentiated granulocytic, megakaryocytic, or erythroid cells obtained from all patients. JAK2V617F up-regulates LMO2 in K562 and in JAK2V617F-positive CD34(+) cells. The selective JAK2 inhibitor AG490 normalizes the LMO2 levels in V617F-positive K562 and restores the cyto-plasmic localization of JAK2.


Assuntos
Antígenos CD34/metabolismo , Núcleo Celular/metabolismo , Células Eritroides/metabolismo , Granulócitos/metabolismo , Janus Quinase 2/genética , Megacariócitos/metabolismo , Transtornos Mieloproliferativos/metabolismo , Cromossomo Filadélfia , Apoptose , Western Blotting , Medula Óssea/metabolismo , Células Cultivadas , Citoplasma/metabolismo , Granulócitos/citologia , Humanos , Janus Quinase 2/metabolismo , Células K562 , Megacariócitos/citologia , Microscopia de Fluorescência , Mutação/genética , Transtornos Mieloproliferativos/genética , Transtornos Mieloproliferativos/patologia , Fosforilação , Prognóstico , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
13.
World J Gastroenterol ; 16(20): 2566-70, 2010 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-20503459

RESUMO

The involvement of the small bowel in systemic forms of amyloidosis may be diffuse or very rarely focal. Some cases of focal amyloidomas of the duodenum and jejunum without extraintestinal manifestations have been reported. The focal amyloidomas consisted of extensive amyloid infiltration of the entire intestinal wall thickness. Radiological barium studies, ultrasound and computed tomography (CT) patterns of diffuse small bowel amyloidosis have been described: the signs are non-specific and may include small-bowel dilatation, symmetric bowel wall thickening, mesenteric infiltration, and mesenteric adenopathy. No data are available about the positron emission tomography (PET)/CT and magnetic resonance imaging (MRI) patterns of intestinal amyloidosis. We report two cases of small bowel amyloidosis: the former characterized by focal deposition of amyloid proteins exclusively within blood vessel walls of the terminal ileum, the latter characterized by diffuse intestinal involvement observed on MRI and PET/CT studies.


Assuntos
Amiloidose/patologia , Enteropatias/patologia , Intestinos/patologia , Idoso , Amiloidose/diagnóstico , Amiloidose/fisiopatologia , Feminino , Humanos , Enteropatias/diagnóstico , Enteropatias/fisiopatologia , Intestinos/fisiopatologia , Masculino , Tomografia por Emissão de Pósitrons/métodos , Tomografia Computadorizada por Raios X/métodos
16.
Cancer Res ; 69(4): 1633-42, 2009 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-19208846

RESUMO

EVI1 is an oncogene inappropriately expressed in the bone marrow (BM) of approximately 10% of myelodysplastic syndrome (MDS) patients. This disease is characterized by severe anemia and multilineage myeloid dysplasia that are thought to be a major cause of mortality in MDS patients. We earlier reported on a mouse model that constitutive expression of EVI1 in the BM led to fatal anemia and myeloid dysplasia, as observed in MDS patients, and we subsequently showed that EVI1 interaction with GATA1 blocks proper erythropoiesis. Whereas this interaction could provide the basis for the erythroid defects in EVI1-positive MDS, it does not explain the alteration of myeloid differentiation. Here, we have examined the expression of several genes activated during terminal myelopoiesis in BM cells and identified a group of them that are altered by EVI1. A common feature of these genes is their regulation by the transcription factor PU.1. We report here that EVI1 interacts with PU.1 and represses the PU.1-dependent activation of a myeloid promoter. EVI1 does not seem to inhibit PU.1 binding to DNA, but rather to block its association with the coactivator c-Jun. After mapping the PU.1-EVI1 interaction sites, we show that an EVI1 point mutant, unable to bind PU.1, restores the activation of PU.1-regulated genes and allows a normal differentiation of BM progenitors in vitro.


Assuntos
Proteínas de Ligação a DNA/fisiologia , Síndromes Mielodisplásicas/genética , Mielopoese/fisiologia , Proteínas Proto-Oncogênicas/genética , Proto-Oncogenes/fisiologia , Transativadores/genética , Fatores de Transcrição/fisiologia , Células 3T3 , Anemia/genética , Animais , Diferenciação Celular , Linhagem Celular , Cromatina/genética , Ensaio de Unidades Formadoras de Colônias , Proteínas de Ligação a DNA/genética , Eritropoese/genética , Regulação da Expressão Gênica , Genes Reporter , Humanos , Luciferases/genética , Proteína do Locus do Complexo MDS1 e EVI1 , Camundongos , Síndromes Mielodisplásicas/patologia , Reação em Cadeia da Polimerase , Proto-Oncogenes/genética , Fatores de Transcrição/genética
17.
Cancer Res ; 69(1): 262-71, 2009 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-19118011

RESUMO

Janus-activated kinase 2 (JAK2) mutations are common in myeloproliferative disorders; however, although they are detected in virtually all polycythemia vera patients, they are found in approximately 50% of essential thrombocythemia (ET) patients, suggesting that converging pathways/abnormalities underlie the onset of ET. Recently, the chromosomal translocation 3;21, leading to the fusion gene AML1/MDS1/EVI1 (AME), was observed in an ET patient. After we forced the expression of AME in the bone marrow (BM) of C57BL/6J mice, all the reconstituted mice died of a disease with symptoms similar to ET with a latency of 8 to 16 months. Peripheral blood smears consistently showed an elevated number of dysplastic platelets with anisocytosis, degranulation, and giant size. Although the AME-positive mice did not harbor Jak2 mutations, the BM of most of them had significantly higher levels of activated Stat3 than the controls. With combined biochemical and biological assays we found that AME binds to the Stat3 promoter leading to its up-regulation. Signal transducers and activators of transcription 3 (STAT3) analysis of a small group of ET patients shows that in about half of the patients, there is STAT3 hyperactivation independently of JAK2 mutations, suggesting that the hyperactivation of STAT3 by JAK2 mutations or promoter activation may be a critical step in development of ET.


Assuntos
Janus Quinase 2/genética , Fator de Transcrição STAT3/biossíntese , Fator de Transcrição STAT3/metabolismo , Trombocitemia Essencial/genética , Idoso , Animais , Plaquetas/patologia , Células da Medula Óssea/patologia , Subunidade alfa 2 de Fator de Ligação ao Core/biossíntese , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Subunidade alfa 2 de Fator de Ligação ao Core/metabolismo , Modelos Animais de Doenças , Ativação Enzimática , Humanos , Janus Quinase 2/metabolismo , Células K562 , Megacariócitos/patologia , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Proteínas de Fusão Oncogênica/biossíntese , Proteínas de Fusão Oncogênica/genética , Proteínas de Fusão Oncogênica/metabolismo , Regiões Promotoras Genéticas , Proteínas Repressoras/biossíntese , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Fator de Transcrição STAT3/genética , Trombocitemia Essencial/sangue , Trombocitemia Essencial/enzimologia , Trombocitemia Essencial/metabolismo , Regulação para Cima
18.
Ann Hematol ; 88(2): 151-8, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18709502

RESUMO

A large proportion of adult patients with acute myeloid leukemia (AML) relapse after treatment, and some of them are resistant to primary induction chemotherapy. Sixty-one patients from seven hematological centers with poor-risk AML, primary refractory (n = 16), or relapsed (n = 45) were treated with a salvage regimen, including fludarabine (2 days) and cytarabine (3 days) in a sequential continuous infusion, associated with liposomal daunorubicin (3 days) (FLAD). Complete response rate was 44% and 56% for refractory and relapsed patients, respectively, with an overall response rate of 52% (32 of 61). Twenty-two patients (36%) were resistant to the salvage therapy. Seven patients (12%) died early during chemotherapy, four of them because of sepsis. Nineteen patients in complete remission (CR) underwent a stem-cell transplant (SCT) procedure: five autologous, nine from a HL-A identical sibling, and five from HL-A matched unrelated donors. Post-treatment aplasia and mucositis were major toxicities. Twenty patients (62.5%) relapsed after this treatment in a median of 7.3 months; ten patients relapsed after a SCT procedure. Nine patients are alive and disease free; three of them were rescued after a further cytotoxic treatment. The FLAD regimen proved to be an effective and well-tolerated treatment, with acceptable toxicity in this group of high-risk patients. A better response rate was obtained in the subgroup of relapsed patients, compared to patients treated for refractory disease. More then half (five of nine) of long-surviving patients are those who were submitted to a transplant procedure; thus, the main indication for FLAD seems to be to try to induce a rapid CR with minimum toxicity in order to perform a transplant as soon as possible.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Citarabina/uso terapêutico , Daunorrubicina/administração & dosagem , Daunorrubicina/uso terapêutico , Leucemia Mieloide Aguda/tratamento farmacológico , Vidarabina/análogos & derivados , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Citarabina/administração & dosagem , Citarabina/efeitos adversos , Daunorrubicina/efeitos adversos , Intervalo Livre de Doença , Feminino , Humanos , Infusões Intravenosas , Leucemia Mieloide Aguda/cirurgia , Lipossomos , Masculino , Pessoa de Meia-Idade , Recidiva , Terapia de Salvação , Transplante de Células-Tronco , Taxa de Sobrevida , Fatores de Tempo , Vidarabina/administração & dosagem , Vidarabina/efeitos adversos , Vidarabina/uso terapêutico
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA