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1.
Oncogene ; 25(54): 7180-91, 2006 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-16732320

RESUMO

The epidermal growth factor (EGF)/EGF-receptor (ErbB1-4) family is involved in the biology of multiple myeloma (MM). In particular, ErbB-specific inhibitors induce strong apoptosis of myeloma cells (MMC) in vitro. To delineate the contribution of the 10 EGF-family ligands to the pathogenesis of MM, we have assessed their expression and biological activity. Comparing Affymetrix DNA-microarray-expression-profiles of CD138-purified plasma-cells from 65 MM-patients and 7 normal individuals to those of plasmablasts and B-cells, we found 5/10 EGF-family genes to be expressed in MMC. Neuregulin-2 and neuregulin-3 were expressed by MMC only, while neuregulin-1, amphiregulin and transforming growth factor-alpha were expressed by both MMC and normal plasma-cells. Using real-time polymerase chain reaction, we found HB-EGF, amphiregulin, neuregulin-1 and epiregulin to be expressed by cells from the bone marrow-environment. Only the EGF-members able to bind heparan-sulphate proteoglycans (HSPGs) - neuregulin-1, amphiregulin, HB-EGF - promote the growth of MMC. Those ligands strongly bind MMC through HSPGs. The binding and the MMC growth activity was abrogated by heparitinase, heparin or deletion of the HS-binding domain. The number of HS-binding EGF ligand molecules bound to MMC was higher than 10(5) molecules/cell and paralleled that of syndecan-1. Syndecan-1, the main HSPG present on MM cells, likely concentrates high levels of HS-binding-EGF-ligands at the cell membrane and facilitates ErbB-activation. Altogether, our data further identify EGF-signalling as promising target for MM-therapy.


Assuntos
Fator de Crescimento Epidérmico/metabolismo , Receptores ErbB/metabolismo , Proteoglicanas de Heparan Sulfato/metabolismo , Mieloma Múltiplo/metabolismo , Transdução de Sinais/fisiologia , Linfócitos B/metabolismo , Proliferação de Células , Fator de Crescimento Epidérmico/genética , Receptores ErbB/genética , Citometria de Fluxo , Expressão Gênica , Perfilação da Expressão Gênica , Células-Tronco Hematopoéticas/metabolismo , Humanos , Ligantes , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Plasmócitos/metabolismo , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sindecana-1/metabolismo
2.
Bone Marrow Transplant ; 30(5): 287-95, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12209350

RESUMO

The use of mycophenolate mofetil (MMF) for prophylaxis of aGVHD and/or for treatment of acute or chronic GVHD is increasing. However, the benefit of MMF as an alternative to commonly used immunosuppressive agents still needs to be assessed. We ran a retrospective study on 21 consecutive patients (median age, 36 years; range, 20-63) with aGVHD or extensive cGVHD following related (17) or unrelated (4) matched donor SCT (BM, 16; PBSC, 5) who received MMF (2 g/day) because of intolerance to or failure of CsA-containing combinations. Four of the six patients with aGVHD responded, and the response rate was 69% in cGVHD patients. We observed neither significant differences in terms of response rate for skin, liver and bowel nor dissociated response in cases of multiple organ involvement (67% of the patients). Response was the same for lichenoid and sclerodermatous skin cGVHD subtypes. No adverse effects, except diarrhea (three patients), were observed. However, 22 opportunistic or serious viral or bacterial infections occurred in 10 patients. Analysis of trough plasma levels showed a trend for a higher mean MPA concentration in patients responding to MMF. Our study highlights the high risk of infectious complications induced by the administration of MMF, an otherwise efficient and well-tolerated treatment for GVHD.


Assuntos
Doença Enxerto-Hospedeiro/tratamento farmacológico , Imunossupressores/administração & dosagem , Ácido Micofenólico/administração & dosagem , Infecções Oportunistas/induzido quimicamente , Doença Aguda , Adulto , Anti-Inflamatórios não Esteroides/administração & dosagem , Biotransformação , Transplante de Medula Óssea/efeitos adversos , Doença Crônica , Avaliação de Medicamentos , Feminino , Doença Enxerto-Hospedeiro/complicações , Doença Enxerto-Hospedeiro/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Ácido Micofenólico/análogos & derivados , Ácido Micofenólico/farmacocinética , Infecções Oportunistas/diagnóstico , Infecções Oportunistas/microbiologia , Transplante de Células-Tronco de Sangue Periférico/efeitos adversos , Estudos Retrospectivos , Risco , Resultado do Tratamento
3.
Blood ; 97(2): 502-8, 2001 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-11154229

RESUMO

One of the best-characterized resistance mechanisms in acute myeloid leukemia (AML) is the drug extrusion mediated by P-glycoprotein (Pgp). Recently the results of workshops organized by several groups concluded that accurate measurement of low activity of Pgp is a difficult goal in clinical samples. Therefore, highly sensitive and specific assays were developed to assess the functionality of Pgp using JC-1, a fluorescent molecule with the different emission wavelength (green and red fluorescence) according to its concentration in 129 AML samples. It was shown that JC-1 (green and red bands) may define 3 groups of patients: resistant (R) (29% of patients), intermediate (I) (36%), and sensitive (S) (35%). In contrast, rhodamine 123 assay detected only the R group defined by JC-1. Nevertheless, the I group has an intermediate expression of Pgp (0.39, 0.29, and 0.19 for the R, I, and S groups, respectively, P =.002), an intermediate biologic profile (percentage of CD34, 95%, 67%, and 44%, respectively, P <.0001; in vitro resistance to daunorubicin, 94 microM, 20 microM, and 12 microM, respectively, P =. 02), and an intermediate prognosis (achievement of complete remission, 55%, 65%, and 87%, P =.006; 3-year disease-free survival, 11%, 16%, and 36%, respectively, P =.005; and 3-year overall survival, 0%, 20%, and 51%, respectively, P <.0001). Therefore, JC-1 appeared to be a more convenient and simple way to detect a functional Pgp in clinical AML samples than rhodamine 123. (Blood. 2001;97:502-508)


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Benzimidazóis , Carbocianinas , Leucemia Mieloide/patologia , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/imunologia , Doença Aguda , Adulto , Idoso , Anticorpos Monoclonais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Estudos de Coortes , Intervalo Livre de Doença , Citometria de Fluxo , Corantes Fluorescentes , Humanos , Imunoensaio/métodos , Imunoensaio/normas , Imunofenotipagem , Leucemia Mieloide/diagnóstico , Leucemia Mieloide/terapia , Pessoa de Meia-Idade , Análise Multivariada , Proteínas de Neoplasias/imunologia , Proteínas de Neoplasias/metabolismo , Prognóstico , Rodaminas , Sensibilidade e Especificidade , Células-Tronco/química , Células-Tronco/patologia , Taxa de Sobrevida , Resultado do Tratamento
4.
Blood ; 96(3): 870-7, 2000 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-10910899

RESUMO

In acute myeloid leukemia (AML) patients, a variety of clinical and biologic parameters, including phenotype, have been examined for potential value in predicting treatment response and survival. The European Group for the Immunological Classification of Leukaemias (EGIL) has proposed that AML be defined immunologically by the expression of 2 or more of the following myeloid markers: myeloperoxidase, CD13, CD33, CDw65, and CD117. With regard to this classification, the prognostic significance of 21 antigens taken separately and with immunophenotypic subgroups were evaluated and compared with other clinical and biological variables in 177 adult AML patients. None of the antigens tested were associated with treatment outcome. In contrast, patients with blasts disclosing a full expression of panmyeloid phenotype (defined by the expression of all 5 myeloid markers) had a higher complete remission rate (P <. 0001) and differed significantly in disease-free survival (P =.02) and overall survival (P =.008) than patients whose cells expressed fewer than 5 of these markers. In multivariate analysis, only age, panmyeloid phenotype, performance status, and permeability glycoprotein activity influence treatment outcome. Cytogenetics was significant in univariate analysis but not in multivariate analysis, most likely because of the redundancy with panmyeloid phenotype and a higher sensitivity of immunophenotyping. Patients whose cells exhibit the panmyeloid phenotype appear to define a relatively homogeneous biological subset of AML. The 4 independent prognostic factors were used to create a prognostic score, defined by the number of factors present. This score permitted a stratification of patients with AML, thereby allowing for the consideration of innovative therapies to improve outcome in the poorer outcome groups.


Assuntos
Antígenos CD , Imunofenotipagem , Leucemia Mieloide/imunologia , Leucemia Mieloide/fisiopatologia , Doença Aguda , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Biomarcadores , Feminino , Humanos , Leucemia Mieloide/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Prognóstico , Resultado do Tratamento
5.
Cancer Genet Cytogenet ; 119(2): 162-4, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10867154

RESUMO

Acute promyelocytic leukemia (APL) is characterized by a specific translocation (15;17)(q22;q21), resulting in the formation of PML/RARalpha chimeric transcripts. We report two female patients with PML/RARalpha-positive classical APL, whose leukemic cells expressed a variant translocation, t(5;15)(q13;q22) and t(15;17)(q22;p13), respectively. Both translocations were confirmed by whole chromosome painting which revealed no apparent involvement of 17q. A two-color fluorescence in situ hybridization with a 5' PML and a 3' RARalpha probe showed, in both cases, the presence of a PML-RARalpha fusion gene, on the der(15)t(5;15) long arm, and on the der(17)t(15;17) short arm, respectively. These two complex rearrangements resulted most probably from a two-step mechanism: (1) a submicroscopic insertion into 15q of a 17q segment including the 3' part of the RARalpha gene; (2) a reciprocal translocation between der(15) and a variable chromosome arm, with a breakpoint distal and proximal to RARalpha insertion in the case of t(5;15) and t(15;17), respectively. Molecular and prognosis significance of these variant translocations are discussed.


Assuntos
Cromossomos Humanos Par 15/genética , Cromossomos Humanos Par 17/genética , Cromossomos Humanos Par 5/genética , Leucemia Promielocítica Aguda/genética , Mutagênese Insercional , Proteínas de Neoplasias/genética , Proteínas de Fusão Oncogênica/genética , Translocação Genética , Idoso , Cromossomos Humanos Par 15/ultraestrutura , Cromossomos Humanos Par 5/ultraestrutura , Evolução Fatal , Feminino , Humanos , Hibridização in Situ Fluorescente , Pessoa de Meia-Idade
6.
Leukemia ; 13(10): 1481-90, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10516746

RESUMO

We reviewed the reports of 784 consecutive patients admitted to our department for newly diagnosed acute myeloid leukemia (AML) over a 16-year period. Median, 5-year and 10-year overall survivals were 9. 5 months, 17.3% and 11.7% respectively. Induction treatment (698 patients) resulted in 50% complete remissions (CR) (from 26.5% in secondary AML to 81.2% in patients <60 years with de novo AML). Period of diagnosis (1980-84/85-89/90-95) demonstrated a major significance for CR achievement and OS in multivariate analysis. In patients >/=60 years (372), CR rate increased (25% to 36.8%, P = 0. 03), and 5-year OS (3.7% to 10.6%, P = 0.022) improved, probably due to an increase in the proportion of patients administered conventional combined chemotherapy (54.5% to 83.8%, P < 0.0001). In younger patients CR rate continuously increased (61.5% to 74.8%, P = 0.028) with an associated improvement of 5-year OS (19.2% to 35.4%). No significant change in DFS and CR durations was observed. This large single center study on a large cohort of unselected AML patients reflects the improvement achieved in the management of AML patients, likely due to improvement of supportive care practices, administration of conventional induction to more elderly patients, and intensification of induction and post-remission treatments in patients <60 years.


Assuntos
Leucemia Mieloide/terapia , Indução de Remissão/métodos , Doença Aguda , Adulto , Antineoplásicos/uso terapêutico , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico , Taxa de Sobrevida
7.
Leuk Lymphoma ; 34(5-6): 561-7, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10492080

RESUMO

Out of 75 consecutive elderly AML patients who did not receive anti-leukemic treatment (52 pts) or failed to respond to differentiating agent (23 pts), 6 patients had survivals of 13.2 to 98 months with treatment restricted to supportive care. This cut-point is far longer than the median survival of the 235 elderly patients (3.5 mo.), either untreated (med. survival: 1 mo.) or treated (with treatment ranging from conventional induction to palliative chemotherapy) (4 mo.), admitted to our department within the same period of time. These cases of smoldering AML (4 women, 2 men) were all of AML2 FAB subtype (4 de novo, 2 post MDS) and presented with a significantly better performance status, lower WBC and circulating blast counts, higher platelet counts and with lower bone marrow infiltration than AML cases with more rapid progression. Cytogenetical analysis when available (3 pts) showed normal karyotypes and clonogenic assay performed in 3 of these patients showed a lack of (2 pts) or reduced in vitro leukemic cell growth (1 pt). The identification of specific characteristics of smoldering leukemia in the elderly might be an important development in the understanding of the physiopathology of acute leukemia and a tool for helping decision-making when selecting the time and intensity of cytotoxic treatment in these older patients.


Assuntos
Anemia Refratária com Excesso de Blastos/diagnóstico , Leucemia Mieloide Aguda/diagnóstico , Idoso , Idoso de 80 Anos ou mais , Anemia Refratária com Excesso de Blastos/mortalidade , Anemia Refratária com Excesso de Blastos/patologia , Crise Blástica/patologia , Exame de Medula Óssea , Progressão da Doença , Evolução Fatal , Feminino , Humanos , Leucemia Mieloide Aguda/mortalidade , Leucemia Mieloide Aguda/patologia , Masculino , Pessoa de Meia-Idade , Cuidados Paliativos , Prognóstico , Estudos Retrospectivos , Índice de Gravidade de Doença , Taxa de Sobrevida , Sobreviventes
8.
Support Care Cancer ; 7(2): 89-94, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10089089

RESUMO

The objective of this trial was to evaluate the potential advantages of the combination of piperacillin and tazobactam in the control of fever in neutropenic patients. In this single-center study, patients who experienced a total of 247 febrile episodes were prospectively randomized to receive either our standard regimen, ceftazidime 3 g/day (1 g t.i.d.) plus tobramycin 3 mg/kg per day (1.5 mg/kg b.i.d.), or piperacillin 12 g/day plus tazobactam 1.5 g/day (4 g+0.5 g t.i.d.) plus tobramycin 3 mg/kg per day (1.5 mg/kg b.i.d.). Vancomycin was added in all cases of persistent fever in the ceftazidime arm, but only when there was microbiologically documented resistance in the piperacillin/tazobactam arm. All 247 episodes were evaluable by "intent-to-treat" analysis. The two populations were well matched in terms of age, gender, underlying disease, chemotherapy received, oral decontamination, clinical and bacterial documentation, and severity and duration of neutropenia. Initial antibacterial therapy was successful (apyrexia at 72 h, without antibiotic change) more frequently (P = 0.008) with the regimen containing piperacillin/tazobactam (54.4%) than with the one including ceftazidime (37.6%). Fewer (P = 0.02) major infectious events (infectious death or delay in treatment of underlying disease due to infection) were observed during piperacillin/ tazobactam treatment (2.6%) than with the ceftazidime regimen (11.3%), despite a lower frequency of glycopeptide addition when piperacillin/tazobactam was used (54.4% versus 77.4%) according to the rules adopted. This trial confirmed the efficacy of the piperacillin/tazobactam combination for empirical treatment of febrile neutropenic patients. This antibiotic combination permitted a dramatic decrease in empiric glycopeptide antibiotic administration in such patients.


Assuntos
Antibacterianos/uso terapêutico , Ceftazidima/uso terapêutico , Cefalosporinas/uso terapêutico , Inibidores Enzimáticos/uso terapêutico , Febre/tratamento farmacológico , Neutropenia/tratamento farmacológico , Ácido Penicilânico/análogos & derivados , Penicilinas/uso terapêutico , Piperacilina/uso terapêutico , Tobramicina/uso terapêutico , Adulto , Antibacterianos/administração & dosagem , Antineoplásicos/uso terapêutico , Bacteriemia/tratamento farmacológico , Infecções Bacterianas/tratamento farmacológico , Estudos de Casos e Controles , Ceftazidima/administração & dosagem , Cefalosporinas/administração & dosagem , Resistência Microbiana a Medicamentos , Quimioterapia Combinada/administração & dosagem , Quimioterapia Combinada/uso terapêutico , Inibidores Enzimáticos/administração & dosagem , Feminino , Febre de Causa Desconhecida/tratamento farmacológico , Neoplasias Hematológicas/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Ácido Penicilânico/administração & dosagem , Ácido Penicilânico/uso terapêutico , Penicilinas/administração & dosagem , Piperacilina/administração & dosagem , Estudos Prospectivos , Tazobactam , Tobramicina/administração & dosagem , Vancomicina/administração & dosagem , Vancomicina/uso terapêutico
10.
Haematologica ; 83(1): 92-3, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9542329

RESUMO

Besides cytopenia related to treatment, several hematological disorders such as anemia, abnormal platelet activity, thrombosis, presence of anticardiolipin or anti-neutrophil antibodies, cyclic neutropenia, and myelodysplasia, have been reported in patients with Crohn's disease (CD). The case we report here is the first one documenting the association of idiopathic thrombocytopenic purpura (ITP) with CD.


Assuntos
Doença de Crohn/complicações , Púrpura Trombocitopênica Idiopática/complicações , Adulto , Anti-Inflamatórios/uso terapêutico , Doença de Crohn/sangue , Doença de Crohn/tratamento farmacológico , Feminino , Humanos , Metilprednisolona/uso terapêutico , Contagem de Plaquetas , Púrpura Trombocitopênica Idiopática/sangue , Púrpura Trombocitopênica Idiopática/tratamento farmacológico
11.
Br J Haematol ; 100(1): 147-55, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9450804

RESUMO

Biphenotypic acute leukaemia (BAL) patients represented 8% of the 287 de novo consecutive adult acute leukaemias (23 BAL, 230 acute myeloid leukaemia (AML) and 34 acute lymphoblastic leukaemia (ALL)) referred to our department during the last 4-year period. Of these 23 BAL patients, 14 patients showed myeloid morphology and nine cases lymphoid morphology according to FAB criteria. There were no differences between lymphoid and myeloid BAL according to clinical and biological presentation and treatment outcome. We confirm the poor prognosis of BAL when compared to AML or ALL seen during the same period of time, in terms of complete remission (47%, 62% and 82% respectively, BAL v AML, NS and BAL v ALL, P = 0.006) and 4-year overall survival (8.1%, 25.8% and 23.8% respectively, BAL v AML, P = 0.05 and BAL v ALL, P = 0.003). Comparing adult BAL patients with AML patients, we found an increase in poor prognostic factors: CD34+ phenotype (82% v 60% respectively, P = 0.03), unfavourable karyotype (60% v 20%, P < 0.0001) and Pgp over-expression by RT-PCR (0.705 v 0.107, P < 0.0001) and flow cytometry (0.824 v 0.391, P = 0.0001). MRP and LRP were not found to be poor prognostic factors. Comparing BAL patients with ALL patients, we found also an increase in poor prognostic factors: age (51 v 39, P = 0.003) and CD34+ phenotype (82% v 50%, P = 0.02). We conclude that BAL patients need a more aggressive treatment procedure, including high-dose AraC or the use of Pgp modulators for first-line therapy.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Aberrações Cromossômicas , Leucemia/genética , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Doença Aguda , Adulto , Idoso , Idoso de 80 Anos ou mais , Intervalo Livre de Doença , Feminino , Citometria de Fluxo , Humanos , Leucemia/metabolismo , Leucemia Mieloide/genética , Leucemia Mieloide/metabolismo , Masculino , Pessoa de Meia-Idade , Fenótipo , Reação em Cadeia da Polimerase , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Prognóstico , Análise de Sobrevida
12.
Pathol Biol (Paris) ; 45(7): 605-11, 1997 Sep.
Artigo em Francês | MEDLINE | ID: mdl-9404487

RESUMO

Chronic myelomonocytic leukemia (CMML) is characterized by the association of myelodysplastic features and proliferation of both granulocytic and monocytic series. This disease frequently indolent, may however demonstrate progressive course and/or transform to acute leukemia. Nosologic and diagnostic problems raised by this malignant hematological pathology, its clinical and biological presentations, and current treatments are reported in this review.


Assuntos
Leucemia Mielomonocítica Crônica/diagnóstico , Adulto , Idoso , Medula Óssea/patologia , Humanos , Leucemia Mielomonocítica Crônica/patologia , Leucemia Mielomonocítica Crônica/terapia , Pessoa de Meia-Idade , Monócitos/patologia , Prognóstico
13.
Leuk Lymphoma ; 26(5-6): 609-13, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9389368

RESUMO

Primary lymphomas arising in the adrenal gland are extremely rare. The presenting symptoms are nonspecific and may be related to lymphoma or to associated adrenal insufficiency. In this report we describe the case of a 61 year old woman with idiopathic thrombocytopenic purpura and primary bilateral non Hodgkin's lymphoma of the adrenals.


Assuntos
Neoplasias das Glândulas Suprarrenais/complicações , Linfoma não Hodgkin/complicações , Púrpura Trombocitopênica Idiopática/complicações , Feminino , Humanos , Pessoa de Meia-Idade
14.
Am J Hematol ; 53(4): 239-41, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8948661

RESUMO

Peripheral cytopenias are common in patients with agnogenic myeloid metaplasia (AMM). They are an important cause of morbidity and mortality, and their treatment is difficult. We report on 4 patients with AMM and severe cytopenia treated with danazol (400-600 mg/ day). Three of them became independent of red blood cell (RBC) transfusion, while the other had a slight reduction in RBC requirement. In addition, correction of thrombocytopenia and disappearance of splenomegaly were observed in 1 and 2 patients, respectively. No side effects were observed. In our experience, danazol appears effective and safe in the subset of patients with AMM whose disease is mainly characterized by bone-marrow failure. These data warrant further studies to evaluate this treatment and explore its mechanism of action.


Assuntos
Danazol/uso terapêutico , Mielofibrose Primária/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Anemia/tratamento farmacológico , Anemia/etiologia , Anemia/terapia , Terapia Combinada , Transfusão de Eritrócitos/estatística & dados numéricos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mielofibrose Primária/complicações , Esplenomegalia/tratamento farmacológico , Esplenomegalia/etiologia
15.
Hum Gene Ther ; 7(11): 1309-22, 1996 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-8818718

RESUMO

Recombinant adeno-associated viruses (rAAV) are attractive tools for gene therapy. We designed plasmids in which the human multidrug resistance gene (hMDR1) cDNA was placed downstream from portions of the 5' end of AAV including either a 234-bp cassette or the entire AAV p5 promoter. The drug-resistant phenotype conferred by the P-glycoprotein (Pgp) efflux pump encoded by the hMDR1 cDNA was used to select NIH-3T3 cells transfected with these plasmids. The 234-bp region alone showed promoter activity similar in strength to that of the entire p5 promoter or the retroviral Harvey murine sarcoma virus long terminal repeat (LTR); this result demonstrates that the 234-bp cassette might be used as a small and efficient promoter in rAAV designed to express large genes approaching the packaging limit of AAV particles. After transfection of AAV-MDR1 vectors, the integration of MDR1 sequences into the host cell genome was demonstrated by fluorescent in situ hybridization (FISH). In addition, Southern analysis of low-molecular-weight DNA extracted from drug-resistant cells grown under continuous selection pressure indicated the persistence of nonintegrated AAV-MDR1 plasmids. Coordinate expression of Pgp and human glucocerebrosidase (hGC) was observed in drug-selected NIH-3T3 cells transfected with a bicistronic vector in which MDR1 cDNA was linked to hGC cDNA via the encephalomyocarditis internal ribosome entry site sequence. Moreover, following a single intravenous injection of the bicistronic vector complexed to cationic liposomes into recipient mice, delivery of MDR1 and GC cDNAs was achieved in all the organs we tested. Our results demonstrate that the efficiency of liposomes as vehicles for in vitro and in vivo gene delivery, the advantages of AAV-vectors, and the use of MDR1 as a selectable marker might be successfully combined in gene therapy protocols.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Dependovirus/genética , Resistência a Múltiplos Medicamentos/genética , Genes MDR , Glucosilceramidase/genética , Regiões Promotoras Genéticas , Células 3T3 , Animais , DNA Complementar , Dependovirus/fisiologia , Expressão Gênica , Genes , Vetores Genéticos , Vírus do Sarcoma Murino de Harvey/genética , Humanos , Hibridização in Situ Fluorescente , Lipossomos , Camundongos , Plasmídeos , Sequências Repetitivas de Ácido Nucleico , Transfecção , Latência Viral
17.
Br J Haematol ; 86(1): 82-91, 1994 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8011551

RESUMO

A retrospective analysis was performed on 235 elderly acute myelogenous leukaemia (AML) patients aged 60 years or more, consecutively admitted to a single haematological department during a 10-year period from 1980 to 1989. 46% of patients received only conventional induction chemotherapy. The rate of inclusion in EORTC cooperative clinical trials was significantly lower than for younger patients despite specific protocols proposed for the elderly since 1983, thus confirming the important selection bias of most published series on elderly AML patients. Compared with treatment results in patients < 60 years, complete remission (CR) rate was lower (33.3% v 65.4%, P < 0.0001), with a marked drop in patients older than 70, and induction death rate was higher (21.3% v 12.5%, P = 0.04). Intrinsic characteristics of leukaemic cells, especially expression of the MDR1 gene, in vitro growth of the leukaemic clonogenic cells and sensitivity to daunorubicin-(+)cytosine arabinoside, did not differ according to age, except that there was a higher incidence of previous myelodysplastic syndromes and a lower incidence of good prognostic cytogenetics in the elderly patients. Thus, treatment failure in elderly AML patients appears to be mainly due to host-related factors (especially performance status and age < or > or = 70 years), and to inadequate treatments. Some elderly patients may have been undertreated because of the planned anthracycline dose reduction, resulting in a higher rate of 'resistant' AML, i.e. patients surviving the induction period without entering into CR, than in younger patients (45.4% v 22.1%, P < 0.0001). 11 patients (4.7%) with untreated or 'resistant' AML survived more than 1 year, while receiving only supportive care. These slowly progressive AML patients were characterized by a good performance status, and lower circulating blast cells and bone marrow blast counts.


Assuntos
Leucemia Mieloide Aguda/tratamento farmacológico , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Aberrações Cromossômicas , Ensaios Clínicos como Assunto , Feminino , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/mortalidade , Masculino , Pessoa de Meia-Idade , Prognóstico , Indução de Remissão , Estudos Retrospectivos , Viés de Seleção
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