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1.
Leukemia ; 28(7): 1486-93, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24406841

RESUMO

Pulmonary hypertension (PH) is a frequently under recognized complication of myelofibrosis (MF). The pathophysiology of PH in MF is unknown and no definitive therapies have been established. We studied 15 patients with MF-associated PH and compared their echocardiographic and PH relevant biomarkers (nitric oxide (NO), N-terminal pro-hormone of brain natriuretic peptide (NT-pro BNP), von Willebrand antigen (vWB), ristocetin-cofactor activity (RCA) and uric acid (UA)) pre- and post-ruxolitinib treatment. Ruxolitinib decreased the plasma levels of NT-pro BNP (73%; P=0.043), UA (60%), vWB (86%) and RCA (73%; P=0.036). Improvements in echocardiographic findings were also seen in 66% of patients (P=0.022). Furthermore, marked increase in NO compared with baseline (69.75 vs 40.1 picomolar (pM); P=0.001) was observed post-ruxolitinib therapy, whereas no changes were noted with conventional therapies. Treatment with ruxolitinib also resulted in the reduction of key cytokines (tumor necrosis factor alpha, interleukin-4 (IL-4), IL-6 and IL-8) and induction of interferon-gamma. Animal studies further supported the role of ruxolitinib in the induction of NO levels. In conclusion, aberrant Janus kinase (JAK)-signal transducer and activator of transcription signaling in MF may mediate PH through dysregulation of NO and cytokine levels, which can be restored by therapy with JAK inhibitors suggesting that inhibition of this pathway is a novel target for the management of patients with PH.


Assuntos
Hipertensão Pulmonar/tratamento farmacológico , Hipertensão Pulmonar/etiologia , Mielofibrose Primária/complicações , Pirazóis/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Animais , Biomarcadores/sangue , Citocinas/sangue , Modelos Animais de Doenças , Ecocardiografia , Feminino , Ferritinas/sangue , Humanos , Hipertensão Pulmonar/diagnóstico , Janus Quinases/antagonistas & inibidores , Masculino , Camundongos Knockout , Pessoa de Meia-Idade , Óxido Nítrico/sangue , Nitrilas , Mielofibrose Primária/sangue , Mielofibrose Primária/genética , Pirimidinas
2.
Eur Respir J ; 31(2): 469-72, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18238952

RESUMO

Rapid oxygen consumption by markedly increased numbers of hypermetabolic leukocytes in leukaemic patients resulting in the apparent diagnosis of hypoxaemia on arterial blood gas analyses is termed leukocyte larceny. In the present report, a case of polycythaemia vera, extreme thrombocytosis, normal leukocyte counts and arterial hypoxaemia in the absence of clinical, radiological or physiological evidence of lung disease is described. This pseudohypoxaemia case was established by pulse oximetry, as well as by incubation of a blood specimen with potassium cyanide, and became less significant after the use of cytoreductive agents showed a proportionate increase in arterial oxygen tension as platelet counts decreased on serial arterial blood gas analyses. The present case report demonstrates spurious hypoxaemia due to extreme thrombocytosis and shows that, beside significant leukocytosis, even markedly elevated platelet counts can cause larceny of arterial blood oxygen.


Assuntos
Hipóxia/etiologia , Consumo de Oxigênio/fisiologia , Policitemia Vera/complicações , Trombocitose/complicações , Idoso , Gasometria , Feminino , Seguimentos , Humanos , Hipóxia/diagnóstico , Hipóxia/terapia , Oximetria/métodos , Flebotomia/métodos , Contagem de Plaquetas , Policitemia Vera/diagnóstico , Policitemia Vera/terapia , Medição de Risco , Índice de Gravidade de Doença , Trombocitose/diagnóstico , Trombocitose/terapia
3.
Haematologica ; 93(1): e1-5, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18166767

RESUMO

Copper deficiency associated with neurological disorders is a well-documented condition. However, hypocupremia is less often recognized as a cause of cytopenias or bone marrow failure. We report an illustrative series of three new cases of bi-lineage cytopenia associated with copper deficiency. We have analyzed clinical features of current and historical cases to identify clues that could facilitate application of appropriate laboratory testing and heighten the level of clinical suspicion. By maintaining an appropriately high level of suspicion for potential copper deficiency and obtaining a serum copper level, bone marrow failure due to this condition can be correctly diagnosed and treated. We suggest that copper deficiency be included in the differential diagnosis of reversible causes of bone marrow failure syndromes including myelodysplastic syndrome.


Assuntos
Anemia/diagnóstico , Medula Óssea/anormalidades , Medula Óssea/patologia , Cobre/deficiência , Adulto , Anemia/complicações , Exame de Medula Óssea , Linhagem da Célula , Cobre/sangue , Cobre/metabolismo , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pancitopenia/diagnóstico , Pancitopenia/etiologia , Doenças do Sistema Nervoso Periférico/etiologia
4.
Leukemia ; 17(6): 1078-84, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12764371

RESUMO

EMA, consisting of etoposide, mitoxantrone, and cytarabine, is a timed-sequential chemotherapy (TSC) regimen and an efficacious option for induction treatment of acute myelogenous leukemia (AML). Hematopoietic growth factors (HGFs) have been shown to recruit leukemic blasts into cell cycle. We postulated the addition of granulocyte colony-stimulating factor (G-CSF) to EMA (EMA-G) might enhance treatment efficacy. EMA-G consisted of mitoxantrone on days 1-3, cytarabine on days 1-3 and 8-10, etoposide on days 8-10, and G-CSF from day 4 until absolute neutrophil count (ANC) >500/microl. In total, 28 patients were enrolled. All patients had newly diagnosed de novo AML. The median age was 42 years. Of the 27 patients with cytogenetic analysis, six had favorable karyotype, 18 intermediate karyotype, and three unfavorable karyotype. The median follow-up was 37.5 months. The median time for both ANC recovery and last platelet transfusion was 26 days. The toxicities associated with this regimen were no more than those expected with the standard chemotherapy. In all, 24 (86%) patients achieved complete remission (CR), three (11%) patients had no response, and one patient died within 24 h of induction therapy before response could be evaluated. Of the 24 patients who achieved CR, 22 received high-dose cytosine arabinoside and two received allogeneic bone marrow transplant as initial postremission therapy. For the whole cohort, the estimated 3-year survival rate was 67%. The median relapse-free survival was 30.5 months. We conclude that EMA-G regimen is a safe regimen and administration of G-CSF during and after induction treatment is not associated with prolongation of marrow aplasia or acceleration of leukemia relapse. It is efficacious for induction therapy for newly diagnosed de novo AML. A high CR rate can be achieved with only one course of this chemotherapy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Leucemia Mieloide/tratamento farmacológico , Doença Aguda , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Citarabina/administração & dosagem , Esquema de Medicação , Etoposídeo/administração & dosagem , Feminino , Fator Estimulador de Colônias de Granulócitos/administração & dosagem , Humanos , Leucemia Mieloide/mortalidade , Leucemia Mieloide/patologia , Masculino , Pessoa de Meia-Idade , Mitoxantrona/administração & dosagem , Cuidados Paliativos , Indução de Remissão , Fatores de Risco , Taxa de Sobrevida , Fatores de Tempo , Resultado do Tratamento
5.
Artigo em Inglês | MEDLINE | ID: mdl-11722976

RESUMO

Erythropoietin (EPO) is an endogenous hormone produced in the kidney that regulates red blood cell production within the body. Since the cloning and first clinical introduction of recombinant erythropoietin (epoetin) in the late 1980s indications and usage of epoetin have expanded significantly. It is estimated that as many as one third of patients with substantial anemia (hemoglobin less than 10.0 g/dL) resulting from chemotherapy for cancer are treated with epoetin. Though use of epoetin may avoid the inconvenience and infectious risk of blood transfusions, it is expensive and its benefit in some clinical scenarios has been modest. Like many new technologies, strong evidence suggesting situations where the benefit is high has lagged behind its adoption by patients and practitioners. As well, epoetin is expensive and third party payers do not always reimburse it. Research suggests there is considerable variation in epoetin usage in practice. To provide guidance to hematology/oncology specialists regarding use of epoetin, the American Society of Hematology (ASH) and the American Society of Clinical Oncology (ASCO) proposed that the Agency for Healthcare Research and Quality (AHRQ) fund an evidence review by one of the Evidence-based Practice Centers (EPC) that would be used to develop evidence-based guidelines for members of the society. This review highlights principles of evidence-based medicine, distills and appraises the evidence in the published literature that supports the use of epoetin, and presents evidence-based recommendations for use of epoetin in situations where benefit is substantiated by high-quality studies. As well, this review addresses some of the difficulties of performing clinical research in this area, provocative research findings that will require further study, and suggestions regarding epoetin in those areas where further strong evidence has yet to be developed.


Assuntos
Eritropoetina/uso terapêutico , Medicina Baseada em Evidências , Anemia/tratamento farmacológico , Anemia/etiologia , Ensaios Clínicos Controlados como Assunto , Humanos , Neoplasias/complicações , Neoplasias/tratamento farmacológico , Guias de Prática Clínica como Assunto , Proteínas Recombinantes/uso terapêutico , Resultado do Tratamento , Estados Unidos , United States Agency for Healthcare Research and Quality
6.
J Natl Cancer Inst ; 93(16): 1204-14, 2001 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-11504766

RESUMO

Epoetin treatment offers an attractive but costly alternative to red blood cell transfusion for managing anemia associated with cancer therapy. The goal of this review is to facilitate more efficient use of epoetin by 1) quantifying the effects of epoetin on the likelihood of transfusion and on quality of life in patients with cancer treatment-related anemia and 2) evaluating whether outcomes are superior when epoetin treatment is initiated at higher hemoglobin thresholds. Two independent reviewers followed a prospective protocol for identifying studies. Outcomes data were combined with the use of a random-effects meta-analysis model. Double-blind, randomized, controlled trials that minimized patient exclusions were defined as higher quality for sensitivity analysis; randomized but unblinded trials and trials with excessive exclusions were included in the meta-analysis but were defined as lower quality. Twenty-two trials (n = 1927) met inclusion criteria, and 12 (n = 1390) could be combined for estimation of odds of transfusion. Epoetin decreased the percentage of patients transfused by 9%-45% in adults with mean baseline hemoglobin concentrations of 10 g/dL or less (seven trials; n = 1080), by 7%-47% in those with hemoglobin concentrations greater than 10 g/dL but less than 12 g/dL (seven trials; n = 431), and by 7%-39% in those with hemoglobin concentrations of 12 g/dL or higher (five trials; n = 308). In sensitivity analysis, the combined odds ratio for transfusion in epoetin-treated patients as compared with controls was 0.45 (95% confidence interval [CI] = 0.33 to 0.62) in higher quality studies and 0.14 (95% CI = 0.06 to 0.31) in lower quality studies. The number of patients needed to treat to prevent one transfusion is 4.4 for all studies, 5.2 for higher quality studies, and 2.6 for lower quality studies. Only studies with mean baseline hemoglobin concentrations of 10 g/dL or less reported statistically significant effects of epoetin treatment on quality of life; quality-of-life data were insufficient for meta-analysis. No studies addressed epoetin's effects on anemia-related symptoms. We conclude that epoetin reduces the odds of transfusion for cancer patients undergoing therapy. Evidence is insufficient to determine whether initiating epoetin earlier spares more patients from transfusion or results in better quality of life than waiting until hemoglobin concentrations decline to nearly 10 g/dL.


Assuntos
Anemia/tratamento farmacológico , Eritropoetina/uso terapêutico , Hematínicos/uso terapêutico , Neoplasias/terapia , Anemia/etiologia , Antineoplásicos/efeitos adversos , Transfusão de Sangue/estatística & dados numéricos , Ensaios Clínicos Controlados como Assunto , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/radioterapia , Razão de Chances , Qualidade de Vida , Radioterapia/efeitos adversos , Projetos de Pesquisa , Sensibilidade e Especificidade
7.
Clin Genet ; 59(5): 360-3, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11359469

RESUMO

Gaucher's disease is an autosomal recessive inherited defect of the lysosomal enzyme glucocerebrosidase, which leads to glucocerebroside accumulation in the reticuloendothelial system. Homozygosity for the D409H mutation has been associated with cardiovascular valvular disease. We present a case of a 17-year-old Palestinian patient who presented with severe aortic and mitral valvular calcification, as well as calcification of the ascending aorta, the aortic arch and the ostia of his coronary arteries. The patient was confirmed to be homozygous for the D409H mutation in the glucocerebrosidase gene. The patient's enzyme assay for glucocerebrosidase activity was 5 nm/h/mg protein (normal 13-22 nm/h/mg). The patient presented with symptoms of dyspnea and chest pain. He had a 6-year history of documented aortic valve calcification by echocardiogram after two of his older brothers died of congestive heart failure and severe valvular calcification. Cardiac catheterization showed a severely calcified aorta with almost no motion of the aortic valve leaflets and severe calcification of the mitral valve and the mitral valvular apparatus. The patient underwent extensive cardiac surgery with aortic and mitral valve replacements and intraoperative findings confirmed calcification of the entire aortic root. Electron microscopy of the valves confirmed the presence of Gaucher's cells. Enzyme therapy with imiglucerase was initiated. The patient is in stable condition, 20 months post-operatively.


Assuntos
Aorta Torácica/patologia , Calcinose/patologia , Doença de Gaucher/genética , Valva Mitral/patologia , Adolescente , Substituição de Aminoácidos , Doença de Gaucher/patologia , Homozigoto , Humanos , Masculino , Microscopia Eletrônica , Valva Mitral/ultraestrutura , Mutação
9.
Am J Clin Oncol ; 24(1): 58-63, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11232951

RESUMO

Remission induction chemotherapy for acute myelogenous leukemia typically combines cytarabine with an anthracycline or anthracycline derivative. To date, no specific combination has emerged as more efficacious than any other. To reduce toxicity and shorten the duration of neutropenia, hematopoietic growth factors are often added to the chemotherapy regimen, especially in elderly patients. In all prospective, randomized, growth factor trials to date, daunorubicin has been the drug selected for combination with cytarabine. We hypothesized that mitoxantrone might be as efficacious in this patient population with perhaps less toxicity when combined with granulocyte-macrophage colony-stimulating factor (GM-CSF). Patients older than age 55 years with a diagnosis of either de novo or secondary, untreated acute myelogenous leukemia were eligible for this clinical trial. Eligible patients were treated with cytarabine 100 mg/m2 infused as a continuous infusion daily for 7 days and mitoxantrone 12 mg/m2 bolus intravenously for the first 3 days of cytarabine. A second cycle of chemotherapy was administered on the fourteenth day of treatment if marrow aplasia was not achieved with the first cycle. Once aplasia was achieved, GM-CSF 250 microg/m2 was given subcutaneously daily until neutrophil recovery. Those patients who achieved complete remission were treated with two cycles of intermediate-dose cytarabine (400 mg/m2 daily for 5 days) and with GM-CSF as consolidation therapy. Of the 30 patients treated, the median age was 69 years (range: 55-76 years) and 18 patients were older than 65 years of age. Seven (23%) patients had secondary acute leukemia and 12 (40%) had poor-risk cytogenetics. Nineteen (63%) achieved a complete remission. Eleven patients were either refractory to treatment or died during their treatment. The toxicity encountered was no more than that reported in similar studies using daunorubicin in combination with cytarabine. Long-term survival was poor, with a median disease-free survival of only 8.1 months in patients who achieved complete remission. In this elderly population of patients with high-risk acute myelogenous leukemia, this combination of cytarabine, mitoxantrone, and GM-CSF resulted in an adequate remission rate with acceptable toxicity. Long-term survival, however, was poor and innovative treatment approaches to maintain remission are needed.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Leucemia Mieloide Aguda/tratamento farmacológico , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Citarabina/administração & dosagem , Feminino , Fator Estimulador de Colônias de Granulócitos e Macrófagos/administração & dosagem , Humanos , Masculino , Pessoa de Meia-Idade , Mitoxantrona/administração & dosagem , Neutrófilos/efeitos dos fármacos
11.
Blood ; 94(5): 1517-36, 1999 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-10477676

RESUMO

Because there are differing opinions regarding treatment of patients in the chronic phase of chronic myeloid leukemia (CML), the American Society of Hematology convened an expert panel to review and document evidence-based benefits and harms of treatment of CML with busulfan (BUS), hydroxyurea (HU), recombinant interferon-alpha (rIFN-alpha), and bone marrow transplantation (BMT). The primary measure for defining efficacy was survival. Analysis indicated a survival advantage for HU over BUS. Observational studies of rIFN-alpha suffer from numerous biases including sample size, variations in study populations, definitions of hematologic and cytogenetic remissions, and dose. That rIFN-alpha is more efficacious than chemotherapy is demonstrated by 6 prospective randomized trials. For patients with favorable clinical features in chronic phase, compared to HU and BUS, rIFN-alpha improves survival by a median of about 20 months. Most evidence suggests that rIFN-alpha is most effective when combined with other drugs and when given during the earliest stage of the chronic phase. Adding cytarabine to rIFN-alpha adds further survival benefit but increases toxicity. Limitations for evaluating the long-term benefits of allogeneic BMT include the retrospective nature of most studies, incomplete documentation of the clinical characteristics of the patients, paucity of the details on patient selection, lack of control groups, and limitations of survival calculations. Survival curves for BMT show that at least half of the patients transplanted remain alive 5 to 10 years after treatment, whereas similar curves for rIFN-alpha show a continuous relapse rate over time with the curves crossing at about 7 to 8 years. Estimates of long-term survival may be confounded by the selection biases mentioned and the analytic methods used. The magnitude of the incremental increase in benefit with BMT must be weighed against the potential serious harm and death that may accompany the procedure in the short term. The best results with BMT have been obtained when it is performed within 1 to 2 years from diagnosis. Since each treatment option involves tradeoffs between benefit and harm, patient choice must be based on the examination of facts presented in an unbiased fashion. Newly diagnosed younger patients and older patients who are candidates for BMT should also be offered information about IFN-based regimens, the tradeoffs involved, and, if possible, share in the treatment decision. Hopefully this analysis will provide the stimulus for evaluation of other important aspects of CML.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Transplante de Medula Óssea , Medicina Baseada em Evidências , Leucemia Mielogênica Crônica BCR-ABL Positiva/terapia , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Bussulfano/efeitos adversos , Bussulfano/uso terapêutico , Terapia Combinada , Humanos , Hidroxiureia/efeitos adversos , Hidroxiureia/uso terapêutico , Interferon-alfa/efeitos adversos , Interferon-alfa/uso terapêutico , Transplante Homólogo
12.
Leuk Res ; 23(9): 787-94, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10475617

RESUMO

The aim of this study is to determine whether the addition of mitoxantrone to high dose cytarabine improves the outcome of treatment in patients with relapsed or refractory acute myeloid leukemia (AML). One hundred and sixty-two eligible patients, 14-76 years of age, with AML either in first relapse or that failed to respond to initial remission induction therapy, with no CNS involvement were randomized to receive therapy with cytarabine 3 gm/M2 i.v. over 2 h every 12 h for 12 doses on days 1-6 (Arm I) (HIDAC); or HIDAC plus mitoxantrone 10 mg/M2 i.v. daily on days 7 9 (Arm II) (HIDAC + M). Patients achieving complete remission were treated with three courses of consolidation including HIDAC (Ara-C 3 gm/M2 i.v. 12 h days 1 3; 2 gm/M2 over age 50) alone (ARM I) or with mitoxantrone (10 mg/M2 i.v. day 1) (ARM II). Among 162 patients (81 HIDAC, 81 HIDAC + M) evaluated for induction toxicity, there were 10 (12%) induction deaths with HIDAC and 13 (17%) with HIDAC + M (2-tailed P = 0.65). Most early deaths were due to infection and/or hemorrhage. Among 162 patients evaluated for responses to induction therapy, 26/81 (32%) HIDAC and 36/81 (44%) HIDAC + M patients achieved complete remission (two-tailed P = 0.15). Although this difference was not statistically significant in univariate analysis, it was after adjusting for the effects of WBC and PMN percentage in multivariate analysis (P=0.013). Median survivals from study entry were 8 months (HIDAC) and 6 months (HIDAC + M); 2-tailed logrank P = 0.58. Among 48 patients registered for consolidation, the median disease-free survivals from that registration were 8 months with HIDAC and 11 months with HIDAC + M (P = 0.60). There were three treatment-related deaths during consolidation (1 HIDAC, 2 HIDAC + M), all due to infections. In this randomized trial, the addition of mitoxantrone to high-dose cytarabine was associated with a trend toward a higher CR rate. There was less evidence for an advantage in disease-free or overall survival, although any such conclusion is limited by the size of the study.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Leucemia Mieloide/tratamento farmacológico , Doença Aguda , Adolescente , Adulto , Idoso , Citarabina/administração & dosagem , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mitoxantrona/administração & dosagem , Prognóstico , Recidiva , Resultado do Tratamento
13.
J Invest Dermatol ; 113(1): 87-92, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10417624

RESUMO

Ferrochelatase, the enzyme that catalyzes the terminal step in the heme biosynthetic pathway, is the site of the defect in the human inherited disease erythropoietic protoporphyria. Molecular genetic studies have shown that the majority of erythropoietic protoporphyria cases are transmitted in dominant fashion and that mutations underlying erythropoietic protoporphyria are heterogeneous. We performed haplotype analysis of American families that shared recurrent ferrochelatase gene mutations yet had forbearers from several European countries. This was to gain insight into whether these mutations represent mutational hotspots at the ferrochelatase gene, or propagation of ancestral alleles bearing the mutations. Two recurrent mutations were found to occur on distinctive chromosome 18 haplotypes, consistent with being hotspot mutations. On the other hand, we found three sets of two unrelated families that shared the same haplotypes bearing these mutations, which could reflect geographic dispersion of ancestral mutant alleles. In addition, we report novel mutations associated with erythropoietic protoporphyria: g(+ 1)-->t transversion of the exon 4 donor site, g(+ 1)-->a transition of the exon 6 donor site, and t(+ 2)-->a substitution at the exon 9 donor site; these mutations are predicted to cause splicing defects of the associated exons. We also identified a g(+ 5)-->a transition of the exon 1 donor site in four unrelated families with erythropoietic protoporphyria, and a G(- 1)-->A substitution at the exon 9 donor site in an additional family. The probability that these sequence changes are normal polymorphisms was virtually excluded (p < 0.0001) by their absence in 120 ferrochelatase alleles from 30 normal subjects and 30 individuals with manifested erythropoietic protoporphyria with or without a known mutation.


Assuntos
Ferroquelatase/genética , Haplótipos , Porfiria Hepatoeritropoética/genética , Processamento Alternativo/genética , Sequência de Bases , DNA/química , DNA/genética , Análise Mutacional de DNA , Éxons/genética , Saúde da Família , Feminino , Humanos , Masculino , Mutação , Linhagem , Mutação Puntual , Porfiria Hepatoeritropoética/enzimologia
15.
Blood ; 92(11): 4336-43, 1998 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-9834240

RESUMO

We report an RNA targeting strategy, which selectively degrades bcr/abl mRNA in chronic myelogenous leukemia (CML) cells. A 2', 5'-tetraadenylate activator (2-5A) of RNase L was chemically linked to oligonucleotide antisense directed against either the fusion site or against the translation start sequence in bcr/abl mRNA. Selective degradation of the targeted RNA sequences was demonstrated in assays with purified RNase L and decreases of p210(bcr/abl) kinase activity levels were obtained in the CML cell line, K562. Furthermore, the 2-5A-antisense chimeras suppressed growth of K562, while having substantially reduced effects on the promyelocytic leukemia cell line, HL60. Findings were extended to primary CML cells isolated from bone marrow of patients. The 2-5A-antisense treatments both suppressed proliferation of the leukemia cells and selectively depleted levels of bcr/abl mRNA without affecting levels of beta-actin mRNA, determined by reverse transcriptase-polymerase chain reaction (RT-PCR). The specificity of this approach was further shown with control oligonucleotides, such as chimeras containing an inactive dimeric form of 2-5A, antisense lacking 2-5A, or chimeras with altered sequences including several mismatched nucleotides. The control oligonucleotides had either reduced or no effect on CML cell growth and bcr/abl mRNA levels. These findings show that CML cell growth can be selectively suppressed by targeting bcr/abl mRNA with 2-5A-antisense for decay by RNase L and suggest that these compounds should be further explored for their potential as ex vivo purging agents of autologous hematopoietic stem cell transplants from CML patients.


Assuntos
Endorribonucleases/genética , Proteínas de Fusão bcr-abl/antagonistas & inibidores , Proteínas de Fusão bcr-abl/genética , Regulação Neoplásica da Expressão Gênica , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , RNA Mensageiro/antagonistas & inibidores , Proteínas Recombinantes de Fusão/genética , Nucleotídeos de Adenina/genética , Nucleotídeos de Adenina/farmacologia , Nucleotídeos de Adenina/uso terapêutico , Endorribonucleases/farmacologia , Ativação Enzimática/genética , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Oligonucleotídeos Antissenso/genética , Oligonucleotídeos Antissenso/farmacologia , Oligonucleotídeos Antissenso/uso terapêutico , Oligorribonucleotídeos/genética , Oligorribonucleotídeos/farmacologia , Oligorribonucleotídeos/uso terapêutico , RNA Mensageiro/genética , Proteínas Recombinantes de Fusão/farmacologia , Proteínas Recombinantes de Fusão/uso terapêutico , Células Tumorais Cultivadas
16.
Cleve Clin J Med ; 65(10): 510-4, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9830783

RESUMO

Clinical guidelines for treating ITP are based on the consensus of an expert panel, as randomized trials are lacking. Newer genetically engineered treatments hold promise but await definitive study.


Assuntos
Púrpura Trombocitopênica Idiopática/diagnóstico , Púrpura Trombocitopênica Idiopática/terapia , Adulto , Contagem de Células Sanguíneas , Exame de Medula Óssea , Criança , Feminino , Humanos , Masculino , Exame Físico , Guias de Prática Clínica como Assunto , Gravidez , Complicações Hematológicas na Gravidez/diagnóstico , Complicações Hematológicas na Gravidez/terapia , Valores de Referência , Esplenectomia
17.
Abdom Imaging ; 23(6): 633-5, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9922200

RESUMO

Littoral cell angioma (LCA) is a rare benign vascular tumor of the spleen. LCA most commonly presents with constitutional symptoms (low grade fever and fatigue) and signs of hypersplenism (anemia and thrombocytopenia). Radiographically and at gross pathology an enlarged spleen containing multiple nodules is most commonly seen. Currently the radiological findings are nonspecific and correlation with clinical findings is necessary to narrow the differential while tissue is required for a definitive diagnosis.


Assuntos
Hemangioma/diagnóstico por imagem , Neoplasias Esplênicas/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Adulto , Diagnóstico Diferencial , Feminino , Hemangioma/patologia , Hemangioma/cirurgia , Humanos , Esplenectomia , Neoplasias Esplênicas/patologia , Neoplasias Esplênicas/cirurgia
18.
Rheum Dis Clin North Am ; 23(2): 425-37, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9156401

RESUMO

Hematologic side effects of rheumatic disease therapies are generally mild and reversible; however, the clinician must be alert for potential profound and life-threatening toxicities. A knowledge of the toxicity patterns for the individual drugs is necessary to anticipate potential complications. Management of acute leukemias and lymphomas arising in patients with connective tissue disorders is particularly challenging. Further data are needed to define the best treatment options and thus enrollment in clinical trials is encouraged for these patients.


Assuntos
Antirreumáticos/efeitos adversos , Doenças Hematológicas/induzido quimicamente , Segunda Neoplasia Primária/induzido quimicamente , Doenças Reumáticas/tratamento farmacológico , Anemia/induzido quimicamente , Anemia/terapia , Humanos , Hospedeiro Imunocomprometido , Leucemia/induzido quimicamente , Leucopenia/induzido quimicamente , Leucopenia/terapia , Linfoma/induzido quimicamente
20.
Bone Marrow Transplant ; 20(9): 761-5, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9384478

RESUMO

A major limitation of ABMT for relapsed/refractory Hodgkin's disease is disease recurrence post-transplantation. We retrospectively reviewed 68 patients undergoing ABMT from January 1987 to June 1993. All received a uniform preparatory regimen (CBV). The median patient age was 30; 75% received prior radiation therapy and all patients received prior chemotherapy. Thirty-one percent presented at the time of transplantation with tumor masses larger than 10 cm. Sixty-two percent received autologous marrow alone and 38% PBPC with or without autologous bone marrow. Overall and progression-free survival are 43 and 36% at 5 years. Median follow-up for survivors is 59 months. Multivariate analysis revealed that tumor bulk was the most powerful poor prognostic factor for both survival and progression-free survival. Those transplanted with non-bulky tumors had an overall survival and progression-free survival of 52 and 44%, respectively, compared to those transplanted with bulky tumors who had an overall survival and progression-free survival of 22 and 16% (P = 0.03 and P = 0.04, respectively). Twenty-seven patients have relapsed. Four relapsed more than 2 years after ABMT. Four of the 27 patients who have relapsed remain alive, two without evidence of disease. The time after transplant to relapse was prognostically important, with no patients who relapsed within 6 months of ABMT still being alive, compared with 25% of patients who relapsed 7 or more months after ABMT who are still alive. We conclude that salvage therapy for relapse after ABMT is appropriate, as some patients may achieve prolonged survival. The time from transplant to relapse is an important survival predictor.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Doença de Hodgkin/terapia , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carmustina/uso terapêutico , Ciclofosfamida/uso terapêutico , Intervalo Livre de Doença , Etoposídeo/uso terapêutico , Feminino , Humanos , Masculino , Estudos Retrospectivos , Condicionamento Pré-Transplante , Resultado do Tratamento
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