RESUMO
BACKGROUND: The incidence of chronic myeloid leukemia (CML) increases with age, but it is unclear how the characteristics of the disease vary with age. In children, where CML is very rare, it presents with more aggressive features, including huge splenomegaly, higher cell count and higher blast cell percentage. PATIENTS AND METHODS: To investigate if after childhood the disease maintains or loses these characteristics of aggressiveness, we analyzed 2784 adult patients, at least 18 years old, registered by GIMEMA CML WP over a 40-year period. RESULTS: Young adults (YAs: 18-29 years old) significantly differed from adults (30-59 years old) and elderly patients (at least 60 years old) particularly for the frequency of splenomegaly (71%, 63% and 55%, P < 0.001), and the greater spleen size (median value: 4.5, 3.0 and 1.0 cm, P < 0.001). According to the EUTOS score, that is age-independent, high-risk patients were more frequent among YAs, than among adult and elderly patients (18%, 9% and 6%, P < 0.001). In tyrosine kinase inhibitors-treated patients, the rates of complete cytogenetic and major molecular response were lower in YAs, and the probability of transformation was higher (16%, 5% and 7%, P = 0.011). CONCLUSIONS: The characteristics of CML or the host response to leukemia differ with age. The knowledge of these differences and of their causes may help to refine the treatment and to improve the outcome. CLINICAL TRIAL NUMBERS: NCT00510926, NCT00514488, NCT00769327, NCT00481052.
Assuntos
Antineoplásicos/uso terapêutico , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Esplenomegalia/epidemiologia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Proteínas Tirosina Quinases/antagonistas & inibidores , Baço/patologia , Adulto JovemRESUMO
TKIs long-term treatment in CML may lead to persistent adverse events (AEs) that can promote relevant morbidity and mortality. Consequently, TKIs dose reduction is often used to prevent AEs. However, data on its impact on successful treatment-free remission (TFR) are quite scarce. We conducted a retrospective study on the outcome of CML subjects who discontinued low-dose TKIs from 54 Italian hematology centers participating in the Campus CML network. Overall, 1.785 of 5.108 (35.0%) regularly followed CML patients were treated with low-dose TKIs, more frequently due to relevant comorbidities or AEs (1.288, 72.2%). TFR was attempted in 248 (13.9%) subjects, all but three while in deep molecular response (DMR). After a median follow-up of 24.9 months, 172 (69.4%) patients were still in TFR. TFR outcome was not influenced by gender, Sokal/ELTS risk scores, prior interferon, number and last type of TKI used prior to treatment cessation, DMR degree, reason for dose reduction or median TKIs duration. Conversely, TFR probability was significantly better in the absence of resistance to any prior TKI. In addition, patients with a longer DMR duration before TKI discontinuation (i.e., >6.8 years) and those with an e14a2 BCR::ABL1 transcript type showed a trend towards prolonged TFR. It should also be emphasized that only 30.6% of our cases suffered from molecular relapse, less than reported during full-dose TKI treatment. The use of low-dose TKIs does not appear to affect the likelihood of achieving a DMR and thus trying a treatment withdrawal, but might even promote the TFR rate.
RESUMO
The therapeutic landscape of chronic myeloid leukemia (CML) has profoundly changed over the past 7 years. Most patients with chronic phase (CP) now have a normal life expectancy. Another goal is achieving a stable deep molecular response (DMR) and discontinuing medication for treatment-free remission (TFR). The European LeukemiaNet convened an expert panel to critically evaluate and update the evidence to achieve these goals since its previous recommendations. First-line treatment is a tyrosine kinase inhibitor (TKI; imatinib brand or generic, dasatinib, nilotinib, and bosutinib are available first-line). Generic imatinib is the cost-effective initial treatment in CP. Various contraindications and side-effects of all TKIs should be considered. Patient risk status at diagnosis should be assessed with the new EUTOS long-term survival (ELTS)-score. Monitoring of response should be done by quantitative polymerase chain reaction whenever possible. A change of treatment is recommended when intolerance cannot be ameliorated or when molecular milestones are not reached. Greater than 10% BCR-ABL1 at 3 months indicates treatment failure when confirmed. Allogeneic transplantation continues to be a therapeutic option particularly for advanced phase CML. TKI treatment should be withheld during pregnancy. Treatment discontinuation may be considered in patients with durable DMR with the goal of achieving TFR.
Assuntos
Antineoplásicos/uso terapêutico , Proteínas de Fusão bcr-abl/antagonistas & inibidores , Mesilato de Imatinib/uso terapêutico , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Compostos de Anilina/uso terapêutico , Tomada de Decisão Clínica , Conferências de Consenso como Assunto , Dasatinibe/uso terapêutico , Gerenciamento Clínico , Proteínas de Fusão bcr-abl/genética , Proteínas de Fusão bcr-abl/metabolismo , Expressão Gênica , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/diagnóstico , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/mortalidade , Expectativa de Vida/tendências , Monitorização Fisiológica , Nitrilas/uso terapêutico , Pirimidinas/uso terapêutico , Qualidade de Vida , Quinolinas/uso terapêutico , Análise de SobrevidaRESUMO
Transfusion-induced iron overload is a frequent problem that clinicians have to face in the treatment of patients affected by both myelodysplastic syndrome (MDS) and primary myelofibrosis (PMF). Different options are currently available for chelation therapy, e.g. oral once-daily administration of the iron chelator deferasirox. In 3 patients with MDS and 1 patient with PMF, deferasirox therapy resulted in an improvement in the hemoglobin level and a reduction in transfusion dependence. Our data open new insights regarding the benefit of iron chelation therapy not only for transfusional iron overload of myelodysplastic and myelofibrotic patients but also for the increase in hemoglobin levels. The biological mechanism of action of deferasirox, an effect which is not shared by other iron chelators, is still obscure and requires further investigations.
Assuntos
Benzoatos/administração & dosagem , Transfusão de Sangue , Hemoglobinas/análise , Síndromes Mielodisplásicas/terapia , Mielofibrose Primária/terapia , Triazóis/administração & dosagem , Idoso , Deferasirox , Feminino , Hemoglobinas/efeitos dos fármacos , Humanos , Quelantes de Ferro/uso terapêutico , Sobrecarga de Ferro/etiologia , Masculino , Síndromes Mielodisplásicas/complicações , Mielofibrose Primária/complicações , Resultado do TratamentoRESUMO
Idiopathic hypereosinophilic syndromes (HES) comprise a spectrum of indolent to aggressive diseases characterized by persistent hypereosinophilia. Hypereosinophilia can result from the presence of a defect in the hematopoietic stem cell giving rise to eosinophilia, it can be present in many myeloproliferative disorders or alternatively it may be a reactive form, secondary to many clinical conditions. The hybrid gene FIP1L1-PDGRFalpha was identified in a subset of patients presenting with HES or chronic eosinophilic leukemia (CEL). In spite of this, the majority of HES patients do not present detectable molecular lesions and for many of them the diagnosis is based on exclusion criteria and sometimes it remains doubt. In this study we explored the possibility to distinguish between HES/CEL and reactive hypereosinophilia based on WT1 transcript amount. For this purpose, 312 patients with hypereosinophilia were characterized at the molecular and cytogenetic level and analyzed for WT1 expression at diagnosis and during follow-up. This study clearly demonstrates that WT1 quantitative assessment allows to discriminate between HES/CEL and reactive eosinophilia and represents a useful tool for disease monitoring especially in the patients lacking a marker of clonality.
Assuntos
Eosinofilia/diagnóstico , Síndrome Hipereosinofílica/diagnóstico , RNA Neoplásico/análise , Proteínas WT1/genética , Adulto , Idoso , Doença Crônica , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Técnicas de Diagnóstico Molecular , Proteínas WT1/análiseRESUMO
Monitoring of BCR-ABL transcripts has become established practice in the management of chronic myeloid leukemia. However, nucleic acid amplification techniques are prone to variations which limit the reliability of real-time quantitative PCR (RQ-PCR) for clinical decision making, highlighting the need for standardization of assays and reporting of minimal residual disease (MRD) data. We evaluated a lyophilized preparation of a leukemic cell line (K562) as a potential quality control reagent. This was found to be relatively stable, yielding comparable respective levels of ABL, GUS and BCR-ABL transcripts as determined by RQ-PCR before and after accelerated degradation experiments as well as following 5 years storage at -20 degrees C. Vials of freeze-dried cells were sent at ambient temperature to 22 laboratories on four continents, with RQ-PCR analyses detecting BCR-ABL transcripts at levels comparable to those observed in primary patient samples. Our results suggest that freeze-dried cells can be used as quality control reagents with a range of analytical instrumentations and could enable the development of urgently needed international standards simulating clinically relevant levels of MRD.
Assuntos
Perfilação da Expressão Gênica/métodos , Perfilação da Expressão Gênica/normas , Reação em Cadeia da Polimerase/métodos , Proteínas Tirosina Quinases/genética , RNA Mensageiro/análise , Liofilização , Proteínas de Fusão bcr-abl , Humanos , Indicadores e Reagentes , Células K562 , Reação em Cadeia da Polimerase/normas , Proteínas Tirosina Quinases/análise , Controle de Qualidade , Padrões de ReferênciaRESUMO
Chronic myelomonocytic leukemia (CMML) is a complex clonal hematological disorder classified among myelodysplastic (MDS)/myeloproliferative neoplasms. Prognosis is poor and there is a lack of effective treatments. The hypomethylating agent decitabine has shown activity against MDS and elderly acute myeloid leukemia, but there is little data focusing specifically on its efficacy in CMML. In this prospective, phase 2 Italian study, CMML patients received intravenous decitabine 20 mg/m2 per day on Days 1-5 of a 28-day treatment cycle. Response was evaluated after four and six cycles; patients responding at the end of six cycles could continue treatment with decitabine. Forty-three patients were enrolled; >50% were high-risk according to four CMML-specific scoring systems. In the intent-to-treat population (n=42), the overall response rate after six cycles was 47.6%, with seven complete responses (16.6%), eight marrow responses (19%), one partial response (2.4%) and four hematological improvements (9.5%). After a median follow-up of 51.5 months (range: 44.4-57.2), median overall survival was 17 months, with responders having a significantly longer survival than non-responders (P=0.02). Grade 3/4 anemia, neutropenia and thrombocytopenia occurred in 28.6%, 50% and 38% of patients, respectively. Decitabine appears to be an effective and well-tolerated treatment for patients with high-risk CMML.
Assuntos
Antimetabólitos Antineoplásicos/administração & dosagem , Decitabina/administração & dosagem , Leucemia Mielomonocítica Crônica/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Itália , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/patologia , Leucemia Mielomonocítica Crônica/patologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Resultado do TratamentoRESUMO
Molecular monitoring for patients with chronic myeloid leukaemia (CML) has become an important practice in the era of imatinib therapy. For successful widespread introduction into the mainstream patient monitoring schedule, many procedural aspects of the complex real-time quantitative polymerase chain reaction (RQ-PCR) technique for measuring BCR-ABL transcripts require optimization. Recommendations for harmonizing the differing methodologies have recently been proposed. These recommendations were designed to maximize reliability of analysis for clinical decision making and proposed the adoption of an International Scale of measurement. The purpose of this review is to present the evidence and supporting data for specific recommendations. These recommendations include use of the same source of cells, either blood or marrow, for analysis; for validation of equal PCR amplification efficiencies of cDNA and standards when using a plasmid to construct standard curves and for ensuring ongoing high-level performance by undertaking a quality assurance programme. Clinicians must know the measurement reliability of an RQ-PCR assay to be able to determine the significance of a change in BCR-ABL level. An assay with poor precision limits the clinical usefulness of results. International harmonization should establish RQ-PCR measurement of BCR-ABL as the best method for monitoring treatment response for patients with CML.
Assuntos
Monitoramento de Medicamentos/métodos , Proteínas de Fusão bcr-abl/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/terapia , Reação em Cadeia da Polimerase/métodos , Humanos , Reação em Cadeia da Polimerase/normas , Controle de Qualidade , RNA Mensageiro/análise , Reprodutibilidade dos TestesRESUMO
Mutations in exon 12 of the nucleophosmin (NPM1) gene occur in about 60% of adult AML with normal karyotype. By exploiting a specific feature of NPM1 mutants, that is insertion at residue 956 or deletion/insertion at residue 960, we developed highly sensitive, real-time quantitative (RQ) polymerase chain reaction (PCR) assays, either in DNA or RNA, that are specific for various NPM1 mutations. In all 13 AML patients carrying NPM1 mutations at diagnosis, cDNA RQ-PCR showed >30 000 copies of NPM1-mutated transcript. A small or no decrease in copies was observed in three patients showing partial or no response to induction therapy. The number of NPM1-mutated copies was markedly reduced in 10 patients achieving complete hematological remission (five cases: <100 copies; five cases: 580-5046 copies). In four patients studied at different time intervals, the number of NPM1 copies closely correlated with clinical status and predicted impending hematological relapse in two. Thus, reliable, sensitive RQ-PCR assays for NPM1 mutations can now monitor and quantify MRD in AML patients with normal karyotype and NPM1 gene mutations.
Assuntos
Dosagem de Genes , Leucemia Mieloide/diagnóstico , Leucemia Mieloide/genética , Neoplasia Residual/diagnóstico , Neoplasia Residual/genética , Proteínas Nucleares/genética , Doença Aguda , Análise Mutacional de DNA/métodos , Perfilação da Expressão Gênica , Humanos , Mutação , Nucleofosmina , Valor Preditivo dos Testes , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodosRESUMO
Imatinib represents at present the most attractive therapy for BCR-ABL positive leukemias, even though a percentage of CML patients develop resistance to this compound. For these resistant patients a therapeutic approach based on a combination of drugs is more likely to be effective. In the last years, constitutive NF-kappaB/Rel activity has been demonstrated in several hematological malignancies. As a result, NFkB/Rel-blocking approaches have been proposed as antineoplastic strategies. Furthermore, the identification of specific kinases within the NF-kappaB activation pathway offers a selective target to address tailored therapies. In the current study, we show that the IKK inhibitor PS1145 is able to inhibit the proliferation of CML cell lines and primary BM cells. Moreover, the addition of Imatinib increases the effects of PS1145 in resistant cell lines and BM cells from resistant patients, with a further increase of apoptosis and inhibition of proliferation and colony growth. Our data provide the rational for a new therapeutic approach, which combines Imatinib and the IKK inhibitor PS1145 in CML resistant patients.
Assuntos
Antineoplásicos/farmacologia , Resistencia a Medicamentos Antineoplásicos , Compostos Heterocíclicos com 3 Anéis/farmacologia , Quinase I-kappa B/antagonistas & inibidores , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , NF-kappa B/antagonistas & inibidores , Piperazinas/uso terapêutico , Piridinas/farmacologia , Pirimidinas/uso terapêutico , Apoptose/efeitos dos fármacos , Benzamidas , Sítios de Ligação , Western Blotting , Células da Medula Óssea/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Terapia Combinada , DNA/metabolismo , Ensaio de Imunoadsorção Enzimática , Humanos , Mesilato de Imatinib , Técnicas In Vitro , Células K562 , NF-kappa B/metabolismo , Ensaio Tumoral de Célula-Tronco/métodosRESUMO
Type 3 haemochromatosis (HFE3) is a rare genetic iron overload disease which ultimately lead to compromised organs functioning. HFE3 is caused by mutations in transferrin receptor 2 (TFR2) gene that codes for two main isoforms (Tfr2α and Tfr2ß). Tfr2α is one of the hepatic regulators of iron inhibitor hepcidin. Tfr2ß is an intracellular isoform of the protein involved in the regulation of iron levels in reticuloendothelial cells. It has been recently demonstrated that Tfr2 is also involved in erythropoiesis. This study aims to further investigate Tfr2 erythropoietic role by evaluating the erythropoiesis of two Tfr2 murine models wherein either one or both of Tfr2 isoforms have been selectively silenced (Tfr2 KI and Tfr2 KO). The evaluations were performed in bone marrow and spleen, in 14 days' and 10 weeks' old mice, to assess erythropoiesis in young versus adult animals. The lack of Tfr2α leads to macrocytosis with low reticulocyte number and increased hemoglobin values, together with an anticipation of adult BM erythropoiesis and an increased splenic erythropoiesis. On the other hand, lack of Tfr2ß (Tfr2 KI mice) causes an increased and immature splenic erythropoiesis. Taken together, these data confirm the role of Tfr2α in modulation of erythropoiesis and of Tfr2ß in favoring iron availability for erythropoiesis.
Assuntos
Hemocromatose/genética , Ferro/metabolismo , Isoformas de Proteínas/genética , Receptores da Transferrina/deficiência , Animais , Modelos Animais de Doenças , Eritropoese/genética , Hemocromatose/patologia , Fígado/metabolismo , Fígado/patologia , Camundongos , Camundongos Knockout , Sistema Fagocitário Mononuclear/metabolismo , Sistema Fagocitário Mononuclear/patologia , Receptores da Transferrina/genética , Baço/metabolismo , Baço/patologiaRESUMO
The single-arm, phase 2 ENESTfreedom trial assessed the potential for treatment-free remission (TFR; i.e., the ability to maintain a molecular response after stopping therapy) following frontline nilotinib treatment. Patients with Philadelphia chromosome-positive chronic myeloid leukemia in chronic phase with MR4.5 (BCR-ABL1⩽0.0032% on the International Scale (BCR-ABL1IS)) and ⩾2 years of frontline nilotinib therapy were enrolled. Patients with sustained deep molecular response during the 1-year nilotinib consolidation phase were eligible to stop treatment and enter the TFR phase. Patients with loss of major molecular response (MMR; BCR-ABL1IS⩽0.1%) during the TFR phase reinitiated nilotinib. In total, 215 patients entered the consolidation phase, of whom 190 entered the TFR phase. The median duration of nilotinib before stopping treatment was 43.5 months. At 48 weeks after stopping nilotinib, 98 patients (51.6%; 95% confidence interval, 44.2-58.9%) remained in MMR or better (primary end point). Of the 86 patients who restarted nilotinib in the treatment reinitiation phase after loss of MMR, 98.8% and 88.4%, respectively, regained MMR and MR4.5 by the data cutoff date. Consistent with prior reports of imatinib-treated patients, musculoskeletal pain-related events were reported in 24.7% of patients in the TFR phase (consolidation phase, 16.3%).
Assuntos
Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Pirimidinas/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/psicologia , Masculino , Pessoa de Meia-Idade , Pirimidinas/efeitos adversos , Qualidade de VidaRESUMO
Philadelphia chromosome-positive (Ph+) acute lymphoblastic leukemia (ALL) has a dismal prognosis. We prospectively evaluated minimal residual disease (MRD) by measuring BCR/ ABL levels with a quantitative real-time PCR procedure after induction and after consolidation in 45 adults with Ph+ ALL who obtained complete hematological remission after a high-dose daunorubicin induction schedule. At diagnosis, the mean BCR-ABL/GUS ratio was 1.55 +/- 1.78. A total of 42 patients evaluable for outcome analysis were operationally divided into two MRD groups: good molecular responders (GMRs; n = 28) with > 2 log reduction of residual disease after induction and > 3 log reduction after consolidation therapy, and poor molecular responders (PMRs; n = 14) who, despite complete hematological remission, had a higher MRD at both time points. In GMR, the actuarial probability of relapse-free, disease-free and overall survival at two years was 38, 27 and 48%, respectively, as compared to 0, 0 and 0% in PMR (P = 0.0035, 0.0076 and 0.0026, respectively). Salvage therapy induced a second sustained complete hematological remission in three GMR patients, but in no PMR patient. Our data indicate that, as already shown in children, adult Ph+ ALL patients have a heterogeneous sensitivity to treatment, and that early quantification of residual disease is a prognostic parameter in this disease.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Proteínas de Fusão bcr-abl/genética , Cromossomo Filadélfia , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Adolescente , Adulto , Antibióticos Antineoplásicos/uso terapêutico , Antimetabólitos Antineoplásicos/uso terapêutico , Antineoplásicos Fitogênicos/uso terapêutico , Asparaginase/uso terapêutico , Citarabina/uso terapêutico , Daunorrubicina/uso terapêutico , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasia Residual/tratamento farmacológico , Neoplasia Residual/genética , Neoplasia Residual/mortalidade , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidade , Valor Preditivo dos Testes , Prognóstico , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Vincristina/uso terapêuticoRESUMO
The DNA obtained from the leukemia cells of an acute lymphoblastic leukemia (ALL, L3 type) with a pre-B-phenotype and a typical t(8;14) chromosomal translocation showed a rearrangement juxtaposing the c-myc gene and the immunoglobulin (Ig) heavy-chain gene enhancer. This abnormality was only present in the leukemia cells of the patient and correlated with the clinical course of the disease. The breakpoint on chromosome 8 occurred within c-myc intron 1, between 790 and 638 base pairs upstream of c-myc exon 2. This breakpoint position was the nearest to the c-myc exon 2 so far described in Burkitt's type lymphoma-leukemias, and it mapped very near to the location of a major cryptic promoter used by truncated c-myc genes. In spite of what was detected in a human lymphoma cell line (Manca) carrying a similar rearrangement, in this case the amount of c-myc transcript was not increased compared to an Epstein-Barr virus-transformed normal lymphoblastoid cell line obtained from the same patient. This may in part be due to the breakpoint position and to the fact that the efficiency of the major cryptic promoter present within the first intron could have been affected by the translocation event. Finally, as previously suggested by others, the phenotype expressed by the leukemia cells supported the notion that this particular type of rearrangement (linking together the c-myc gene and the Ig heavy-chain gene enhancer element) may be associated with a subgroup of B-ALLs showing an immunologic phenotype relatively more immature than that of classical B-ALL.
Assuntos
DNA de Neoplasias/análise , Elementos Facilitadores Genéticos , Genes Reguladores , Cadeias Pesadas de Imunoglobulinas/genética , Leucemia Linfoide/genética , Proto-Oncogenes , Recombinação Genética , Adulto , Humanos , Leucemia Linfoide/imunologia , Masculino , RNA Neoplásico/análise , Translocação GenéticaRESUMO
The human leukemic T-cell line Hut 78, derived from a patient suffering from Sézary syndrome and expressing a mature postthymic membrane phenotype, shows a c-myc rearrangement beginning within 500 base pairs immediately 3' to the c-myc exon 3. Chromosome analysis of the Hut 78 reveals the presence of a hyperdiploid karyotype with a large number of markers and rearrangements, though trisomy is the only cytogenetic anomaly involving chromosome 8. Moreover, as the abnormal c-myc appears to be duplicated, a duplication of the chromosome 8 carrying the abnormal c-myc probably occurred. Unlike four other human leukemic T-cell lines tested, the Hut 78 cells express a high amount of c-myc transcript, suggesting that the 3' c-myc anomaly may cause a deregulation of the expression of this gene.
Assuntos
DNA de Neoplasias/genética , Proto-Oncogenes , Síndrome de Sézary/genética , Linfócitos T/fisiologia , Sequência de Bases , Linhagem Celular , Enzimas de Restrição do DNA , Regulação da Expressão Gênica , Genes , Humanos , CariotipagemRESUMO
Several reports have suggested that the mechanism of protection induced by antiidiotypic vaccination against low-grade lymphoproliferative disorders is likely to be antibody mediated. Here we test the hypothesis that DNA vaccination with the short peptide encompassing the complementary-determining region 3 hypervariable region of immunoglobulin heavy chain (VH-CDR3) may elicit a specific antibody immune response able to recognize the native antigens in the form required for therapy. As a test system, we used the VH-CDR3 sequences derived from two patients with non-Hodgkin's B lymphomas (PA, AS) and one patient with hairy cell leukemia (BA) to immunize outbred Swiss mice. This experimental model could mimic a clinical setting in which different patients present distinct HLA haplotypes. Individual tumor-specific VH-CDR3 sequences were amplified by a two-step procedure and directly cloned into multigenic plasmid vectors (pRC100 and derived) with and without mouse interleukin 2 (mIL-2). Each tumor-specific sequence was characterized by sequencing. Female Swiss mice were vaccinated i.m. with plasmids expressing the tumor-specific VH-CDR3 sequence alone (pRC101-PA), mIL-2 plus the VH-CDR3 sequence (pRC111-PA), or a different unrelated antigen (NS3 of hepatitis C virus; pRC112), the sole mIL-2 (pRC110), and the empty plasmid (pRC100). Boost injections were performed at 3 and 16 weeks from the first vaccination, and sera were drawn before each vaccination and at 6, 9, and 19 weeks. Induction of anti-VH-CDR3s antibodies in the sera and their ability to recognize native antigens on patients' tumor cells were evaluated by FACS analysis. Up to 56% (n = 25) of mice vaccinated with pRC111-PA plasmid and 20% (n = 15) of mice vaccinated with pRC101-PA developed a specific immune response that was maintained throughout 19 weeks of observation in 40% of pRC111-PA-vaccinated mice. No response was detected in sera obtained from mice vaccinated with the other plasmids (n = 45). pRC111-PA injection s.c. was less effective (13%, n = 15) than i.m. injection (53%, n = 15). Indeed, we demonstrated that antibodies elicited by naked DNA vaccination against three different patient-derived VH-CDR3 peptides (pRC111-PA or BA or AS) readily reacted with binding epitopes on the idiotypic proteins expressed on the surface of tumor cells derived from each patient; 60, 40, and 40% of, respectively, PA-, BA-, and AS-vaccinated mice developed specific antibodies. No cross-reactivity was detected among the three different CDR3s against tumor cells derived from the other two patients. The outbred mouse strategy confirmed the significant matching potential of three different VH-CDR3 peptides to be efficaciously presented through different MHCs. We conclude that individual VH-CDR3 DNA vaccination can result in a potentially effective specific immune response against non-Hodgkin's B lymphoma cells by a rapid and low-cost therapeutic approach.
Assuntos
Anticorpos Antineoplásicos/imunologia , Vacinas Anticâncer/imunologia , Regiões Determinantes de Complementaridade/imunologia , Leucemia de Células B/imunologia , Linfoma de Células B/imunologia , Vacinas de DNA/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Anti-Idiotípicos/biossíntese , Anticorpos Anti-Idiotípicos/imunologia , Anticorpos Antineoplásicos/biossíntese , Anticorpos Antineoplásicos/sangue , Sequência de Bases , Linhagem Celular Transformada , Epitopos/imunologia , Citometria de Fluxo , Vetores Genéticos/administração & dosagem , Vetores Genéticos/imunologia , Humanos , Cadeias Pesadas de Imunoglobulinas/imunologia , Idiótipos de Imunoglobulinas/imunologia , Região Variável de Imunoglobulina/imunologia , Interleucina-2/biossíntese , Leucemia de Células Pilosas/imunologia , Camundongos , Dados de Sequência MolecularRESUMO
In the phase 3 Evaluating Nilotinib Efficacy and Safety in Clinical Trials-Newly Diagnosed Patients (ENESTnd) study, nilotinib resulted in earlier and higher response rates and a lower risk of progression to accelerated phase/blast crisis (AP/BC) than imatinib in patients with newly diagnosed chronic myeloid leukemia in chronic phase (CML-CP). Here, patients' long-term outcomes in ENESTnd are evaluated after a minimum follow-up of 5 years. By 5 years, more than half of all patients in each nilotinib arm (300 mg twice daily, 54%; 400 mg twice daily, 52%) achieved a molecular response 4.5 (MR(4.5); BCR-ABL⩽0.0032% on the International Scale) compared with 31% of patients in the imatinib arm. A benefit of nilotinib was observed across all Sokal risk groups. Overall, safety results remained consistent with those from previous reports. Numerically more cardiovascular events (CVEs) occurred in patients receiving nilotinib vs imatinib, and elevations in blood cholesterol and glucose levels were also more frequent with nilotinib. In contrast to the high mortality rate associated with CML progression, few deaths in any arm were associated with CVEs, infections or pulmonary diseases. These long-term results support the positive benefit-risk profile of frontline nilotinib 300 mg twice daily in patients with CML-CP.
Assuntos
Mesilato de Imatinib/administração & dosagem , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mieloide de Fase Crônica/tratamento farmacológico , Pirimidinas/administração & dosagem , Glicemia/metabolismo , Colesterol/sangue , Seguimentos , Humanos , Mesilato de Imatinib/farmacologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/sangue , Leucemia Mielogênica Crônica BCR-ABL Positiva/mortalidade , Leucemia Mieloide de Fase Crônica/sangue , Leucemia Mieloide de Fase Crônica/mortalidade , Pirimidinas/farmacologia , Medição de Risco , Resultado do TratamentoRESUMO
The Evaluating Nilotinib Efficacy and Safety in Clinical Trials as First-Line Treatment (ENEST1st) study included 1089 patients with newly diagnosed chronic myeloid leukemia in chronic phase. The rate of deep molecular response (MR(4) (BCR-ABL1⩽0.01% on the International Scale or undetectable BCR-ABL1 with ⩾10,000 ABL1 transcripts)) at 18 months was evaluated as the primary end point, with molecular responses monitored by the European Treatment and Outcome Study network of standardized laboratories. This analysis was conducted after all patients had completed 24 months of study treatment (80.9% of patients) or discontinued early. In patients with typical BCR-ABL1 transcripts and ⩽3 months of prior imatinib therapy, 38.4% (404/1052) achieved MR(4) at 18 months. Six patients (0.6%) developed accelerated or blastic phase, and 13 (1.2%) died. The safety profile of nilotinib was consistent with that of previous studies, although the frequencies of some nilotinib-associated adverse events were lower (for example, rash, 21.4%). Ischemic cardiovascular events occurred in 6.0% of patients. Routine monitoring of lipid and glucose levels was not mandated in the protocol. These results support the use of frontline nilotinib, particularly when achievement of a deep molecular response (a prerequisite for attempting treatment-free remission in clinical trials) is a treatment goal.
Assuntos
Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Tirosina Quinases/antagonistas & inibidores , Pirimidinas/uso terapêutico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Proteínas de Fusão bcr-abl/genética , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/mortalidade , Masculino , Pessoa de Meia-Idade , Pirimidinas/efeitos adversosRESUMO
Molecular monitoring of chronic myeloid leukemia patients using robust BCR-ABL1 tests standardized to the International Scale (IS) is key to proper disease management, especially when treatment cessation is considered. Most laboratories currently use a time-consuming sample exchange process with reference laboratories for IS calibration. A World Health Organization (WHO) BCR-ABL1 reference panel was developed (MR(1)-MR(4)), but access to the material is limited. In this study, we describe the development of the first cell-based secondary reference panel that is traceable to and faithfully replicates the WHO panel, with an additional MR(4.5) level. The secondary panel was calibrated to IS using digital PCR with ABL1, BCR and GUSB as reference genes and evaluated by 44 laboratories worldwide. Interestingly, we found that >40% of BCR-ABL1 assays showed signs of inadequate optimization such as poor linearity and suboptimal PCR efficiency. Nonetheless, when optimized sample inputs were used, >60% demonstrated satisfactory IS accuracy, precision and/or MR(4.5) sensitivity, and 58% obtained IS conversion factors from the secondary reference concordant with their current values. Correlation analysis indicated no significant alterations in %BCR-ABL1 results caused by different assay configurations. More assays achieved good precision and/or sensitivity than IS accuracy, indicating the need for better IS calibration mechanisms.
Assuntos
Proteínas de Fusão bcr-abl/análise , Calibragem , Proteínas de Fusão bcr-abl/normas , Genes abl , Humanos , Reação em Cadeia da Polimerase , Proteínas Proto-Oncogênicas c-bcr/genética , Padrões de Referência , Organização Mundial da SaúdeRESUMO
The proto-oncogene MYC is rearranged at its 3' end in the human T-cell leukemia line Hut 78 as a result of a translocation between the long arms of chromosomes 8 and 2. The nucleotide sequence at the breakpoint shows that the rearranged allele of MYC is truncated 24 nucleotides before the first poly(A)-addition signal. The 3' truncated MYC lacks a 61 nucleotide AT-rich sequence that has been reported to mediate selective mRNA degradation. We show that the truncation results in prolonged stability of MYC mRNA: the half life of the MYC mRNA in Hut 78, as well as in Rat 1A cells transfected with the truncated allele of MYC is increased by at least 5-fold. Our results document yet another mechanism by which MYC may be rendered pathogenic and dramatize the importance of mRNA stability in the regulation of MYC activity.