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1.
Ann Hematol ; 96(7): 1185-1196, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28389687

RESUMO

Treatment of chronic lymphocytic leukemia (CLL) has advanced with the introduction of chemoimmunotherapy (CIT) agents that have improved the outcomes of frontline therapy. However, most treated patients will relapse and require subsequent therapy. This review focuses on recent advances in the treatment of relapsed or refractory CLL. Until recently, treatment options for relapsed CLL were of limited efficacy. Retreatment with fludarabine, cyclophosphamide, and rituximab (FCR) was recommended for patients with a durable response to first-line FCR, although acquired genetic aberrations, impaired marrow reserve, and comorbidities often made this suboptimal therapy for many patients. New options include two agents targeting B cell receptor (BCR) signaling pathways (ibrutinib and idelalisib) and a B cell lymphoma-2 (BCL-2) inhibitor (venetoclax). Allogeneic hematopoietic stem cell transplantation (HSCT) remains a potentially curative option for younger patients with a suitable donor.


Assuntos
Tratamento Farmacológico/métodos , Transplante de Células-Tronco Hematopoéticas/métodos , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Leucemia Linfocítica Crônica de Células B/terapia , Adenina/análogos & derivados , Compostos Bicíclicos Heterocíclicos com Pontes/uso terapêutico , Resistencia a Medicamentos Antineoplásicos , Tratamento Farmacológico/tendências , Transplante de Células-Tronco Hematopoéticas/tendências , Humanos , Leucemia Linfocítica Crônica de Células B/patologia , Piperidinas , Purinas/uso terapêutico , Pirazóis/uso terapêutico , Pirimidinas/uso terapêutico , Quinazolinonas/uso terapêutico , Recidiva , Sulfonamidas/uso terapêutico , Transplante Homólogo
2.
Curr Oncol ; 23(1): 42-51, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26966403

RESUMO

Infections are a major cause of morbidity and mortality in patients with chronic lymphocytic leukemia (cll), who typically have increased susceptibility because of hypogammaglobulinemia (hgg) related to their disease and its treatment. Immunoglobulin replacement therapy (igrt) has been shown to reduce the frequency of bacterial infections and associated hospitalizations in patients with hgg or a history of infection, or both. However, use of igrt in cll is contentious. Studies examining such treatment were conducted largely before the use of newer chemoimmunotherapies, which can extend lifespan, but do not correct the hgg inherent to the disease. Thus, the utility of igrt has to be re-evaluated in the current setting. Here, we discuss the evidence for the use of igrt in cll and provide a practical approach to its use in the prevention and management of infections.

3.
Leukemia ; 31(11): 2443-2448, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28620163

RESUMO

Introduction of new myeloma therapies offers new options for patients refractory to immunomodulatory drugs (IMiDs) and proteasome inhibitors (PIs). In this multicenter study, patients with relapsed multiple myeloma, who have received at least three prior lines of therapy, are refractory to both an IMiD (lenalidomide or pomalidomide) and a PI (bortezomib or carfilzomib), and have been exposed to an alkylating agent were identified. The time patients met the above criteria was defined as time zero (T0). Five hundred and forty-three patients diagnosed between 2006 and 2014 were enrolled in this study. Median age at T0 was 62 years (range 31-87); 61% were males. The median duration between diagnosis and T0 was 3.1 years. The median number of lines of therapy before T0 was 4 (range 3-13). The median overall survival (OS) from T0 for the entire cohort was 13 (95% confidence interval (CI) 11, 15) months. At least one regimen recorded after T0 in 462 (85%) patients, with a median (95% CI) progression-free survival and OS from T0 of 5 (4, 6), and 15.2 (13, 17) months, respectively. The study provides the expected outcome of relapsed multiple myeloma that is refractory to a PI and an IMiD, a benchmark for comparison of new therapies being evaluated.


Assuntos
Adjuvantes Imunológicos/uso terapêutico , Mieloma Múltiplo/tratamento farmacológico , Inibidores de Proteassoma/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/patologia , Prognóstico , Recidiva , Análise de Sobrevida
4.
J Clin Oncol ; 13(9): 2354-60, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7666094

RESUMO

PURPOSE: To determine whether interferon maintenance therapy improves overall survival and response duration in patients with multiple myeloma who have responded to induction therapy with melphalan and prednisone. PATIENTS AND METHODS: In a multicenter trial, patients with symptomatic clinical stage I and stage II and III multiple myeloma were registered at diagnosis and those who responded to melphalan-prednisone (MP) were randomized either to receive interferon (2 mU/m2) subcutaneously three times per week or no maintenance. MP was discontinued in both groups once a stable response plateau of the monoclonal protein was reached. Interferon was continued until relapse, and then was restarted on subsequent response to MP. Interferon toxicity was recorded using a self-report diary. Survival and response duration were calculated using life-table methods, and were adjusted in the analysis for imbalances in baseline prognostic factors. RESULTS: Four hundred two patients were registered and 176 responders were randomized (85 to interferon and 91 to control). At a median follow-up time of 43 months, the median survival duration was 43 months for interferon and 35 months for control (P = .16), but when adjusted for chance imbalances in baseline prognostic factors (mainly performance status), the median survival duration was 44 months and 33 months for interferon and control, respectively (P = .049). Progression-free survival from randomization to first relapse also favored interferon (unadjusted P < .002; adjusted P < .003). Interferon toxicity caused 58% of patients to reduce their dose, of which 84% were able to return to the initial dose; 14% had to discontinue interferon treatment. CONCLUSION: Interferon maintenance therapy improves progression-free and overall survival of patients with multiple myeloma who respond to melphalan and prednisone. Toxicity is substantial and must be weighed by patients against the potential benefits in response duration and survival.


Assuntos
Interferon-alfa/uso terapêutico , Mieloma Múltiplo/terapia , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Canadá , Distribuição de Qui-Quadrado , Terapia Combinada , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Interferon alfa-2 , Interferon-alfa/efeitos adversos , Tábuas de Vida , Masculino , Melfalan/administração & dosagem , Pessoa de Meia-Idade , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/mortalidade , Prednisona/administração & dosagem , Prognóstico , Modelos de Riscos Proporcionais , Proteínas Recombinantes , Indução de Remissão , Taxa de Sobrevida
5.
J Clin Oncol ; 15(4): 1638-45, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9193364

RESUMO

PURPOSE: This randomized, prospective trial compares outcomes for patients with advanced Hodgkin's disease treated with mechlorethamine, vincristine, procarbazine, and prednisone (MOPP)/doxorubicin, bleomycin, and vinblastine (ABV) hybrid regimen or alternating MOPP/doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD). METHODS: Three hundred one patients with advanced Hodgkin's disease were randomized to receive MOPP/ ABV hybrid regimen or alternating MOPP/ABVD after stratification for prior treatment, B symptoms, and treatment center. Eligible patients were either previously untreated and found to have stage IIIB, IVA, or IVB disease or previously treated with wide-field irradiation. Responding patients received a minimum of eight cycles of chemotherapy. Those with residual disease in a localized region received irradiation between the sixth and seventh cycle of treatment. RESULTS: Response rates to the two regimens were similar. Five-year overall survival rates were 81% and 83% for MOPP/ABV hybrid and alternating MOPP/ ABVD, respectively (P = .74; 95% confidence interval [CI] for the difference, -11% to 7%). Five-year failure-free survivals were 71% and 67% for MOPP/ABV hybrid and alternating MOPP/ABVD, respectively (P = .87; 95% CI for the difference, -9% to 17%). Significantly more episodes of febrile neutropenia and stomatitis were observed with the MOPP/ABV hybrid regimen; there was no significant difference in fatal toxicity. Patients with predefined, high-quality partial responses (PR-1s) had results similar to those with complete responses (CRs). Planned subset analysis showed no significant difference in outcome between the two arms of the trial for patients with newly diagnosed disease (5-year failure-free survival rates were 70% for MOPP/ABV hybrid and 59% for alternating MOPP/ABVD; P = .180), but superiority of alternating MOPP/ABVD for patients with prior irradiation (5-year failure-free survival 94% v 73%; P = .017). CONCLUSION: MOPP/ABV hybrid and alternating MOPP/ABVD regimens are equally effective for patients with advanced Hodgkin's disease.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Doença de Hodgkin/tratamento farmacológico , Análise Atuarial , Adolescente , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Bleomicina/administração & dosagem , Canadá , Dacarbazina/administração & dosagem , Intervalo Livre de Doença , Doxorrubicina/administração & dosagem , Esquema de Medicação , Feminino , Doença de Hodgkin/patologia , Humanos , Masculino , Mecloretamina/administração & dosagem , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prednisona/administração & dosagem , Procarbazina/administração & dosagem , Análise de Sobrevida , Resultado do Tratamento , Vimblastina/administração & dosagem , Vincristina/administração & dosagem
6.
J Leukoc Biol ; 61(1): 96-105, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9000542

RESUMO

In the mouse, mutations at the natural resistance-associated macrophage protein 1 (Nramp1) gene abrogate resistance to infection with antigenically unrelated intracellular parasites such as Mycobacterium, Salmonella, and Leishmania. Nramp1 expression is restricted to reticuloendothelial organs and peripheral blood leukocytes, where the protein may function as a membrane transporter of an as yet to be identified substrate. To identify the human blood cell type(s) expressing NRAMP1 mRNA and determine how Nramp1 expression is regulated in these cells, we have examined separated populations of peripheral blood leukocytes and in vitro cell lines. We observed that polymorphonuclear leukocytes (PMN) are the major site of NRAMP1 expression, followed to a lesser degree by monocytes (MN). Migration of MN to tissues (alveolar macrophages) or maturation in vitro (long-term culture) was associated with a higher level of NRAMP1 expression compared with blood MN. Northern analyses of RNA from model cultured cells showed absence of NRAMP1 expression in transformed cell lines from either erythroid or lymphoid T or B lineages as well as progenitors of the monocyte/macrophage pathway (KG1, U937, THP1), and the HL-60 promyelocytic leukemia. Induction of differentiation of HL-60 cells toward either the monocyte/macrophage (vitamin D3, phorbol ester) or the granulocyte pathways (DMF, DMSO), as measured by induction of IL8-Rb, c-FMS, and CD14 marker gene expression, was concomitant with a strong induction of NRAMP1 expression. These results suggest that NRAMP1 expression is specific to the myeloid lineage and is acquired during the maturation of PMN and MN. The possibility that NRAMP1 may be a component of the phagosomal/endosomal apparatus common to PMN and MN is discussed.


Assuntos
Proteínas de Transporte/metabolismo , Proteínas de Transporte de Cátions , Proteínas de Membrana/metabolismo , Neutrófilos/metabolismo , RNA Mensageiro/metabolismo , Sequência de Bases , Proteínas de Transporte/genética , Células HL-60/metabolismo , Humanos , Células Jurkat/metabolismo , Proteínas de Membrana/genética , Dados de Sequência Molecular , Alinhamento de Sequência , Especificidade da Espécie , Células Tumorais Cultivadas/metabolismo
7.
Arch Intern Med ; 137(11): 1621-2, 1977 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-921453

RESUMO

Gardner-Diamond's syndrome, or autoerythrocyte sensitization, is a disorder of spontaneous, painful ecchymoses whose pathogenesis is unresolved. The role of psychopathologic factors in this entity has been emphasized in previous reports. The patient in this study had a classical history and characteristic clinical features and is, to my knowledge, the first man described with this disorder.


Assuntos
Equimose , Adulto , Equimose/complicações , Equimose/diagnóstico , Equimose/psicologia , Humanos , Masculino , Síndrome
8.
J Bone Miner Res ; 5(2): 105-13, 1990 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2316398

RESUMO

We have examined circulating concentrations of a parathyroid hormone-like peptide (PLP) in patients with malignancies and in patients with hyperparathyroidism. The radioimmunoassay employed reacts with synthetic amino-terminal fragments of PLP but not with parathyroid hormone. Elevated plasma PLP concentrations were observed in 50% of patients with malignancy and hypercalcemia and in 15% of normocalcemic cancer patients, mean values being higher in the former group. Detectable plasma PLP concentrations were found in 2 of 39 control subjects. In 2 patients with breast cancer plasma PLP declined concomitantly with a reduction in tumor burden. Adenocarcinoma of the breast and squamous cell carcinomas were most frequently associated with high plasma PLP levels although a variety of histologic types were represented. The presence of metastases on bone scans did not correlate with either the severity of hypercalcemia or the extent of PLP elevation. Increased concentrations of plasma PLP were also observed in 4 of 20 patients with primary hyperparathyroidism and in 5 of 16 patients with chronic renal failure and secondary hyperparathyroidism. Gel filtration analysis of immunoreactive PLP in plasma from 2 hypercalcemic breast cancer patients revealed heterogeneity, with, in each case, both large (greater than 15 kD) and small (6-7 kD) molecular weight amino-terminal moieties. The results document the presence of PLP in the circulation of patients with cancer and are consistent with a pathogenetic role for PLP in the hypercalcemia of malignancy irrespective of whether skeletal metastases have occurred. PLP may also contribute to the skeletal and/or renal manifestations of hyperparathyroid states.


Assuntos
Hiperparatireoidismo/sangue , Neoplasias/sangue , Hormônio Paratireóideo/sangue , Peptídeos/sangue , Adulto , Idoso , Cromatografia em Gel , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Radioimunoensaio
9.
Am J Med ; 100(4): 406-11, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8610726

RESUMO

PURPOSE: To determine whether parathyroid-hormone-related peptide (PTHRP) is an important pathogenetic mediator of hypercalcemia in patients with hematologic malignancies. PATIENTS AND METHODS: We conducted a cohort analytic study in 76 consecutive patients with non-Hodgkin's lymphoma (NHL), Hodgkin's disease, multiple myeloma, and Waldenstrom's macroglobulinemia, 14 of which were hypercalcemic. Thirty normal subjects served as a control group. RESULTS: Using the NH2 -terminal radioimmunoassay, PTHRP concentrations in heavy controls were undetectable (<7.5 pmol equivalents of PTHRP [fragment 1-34] per liter). The majority of hypercalcemic patients (8/14) had non-Hodgkin's lymphoma, and 62.5% of these (5/8) had significant elevations of circulating PTHRP concentrations (mean 70.5 +/- 38.5 pmol equivalents of PTHRP per liter) (P <0.01). In non-Hodgkin's lymphoma, 11 of 30 patients with advanced disease (stage IV) had elevated PTHRP concentrations, and of these, 8 of 11 had high-grade pathology. In contrast, only 3 or 21 patients with less advanced disease (stage I to III) had elevated PTHRP concentrations. In 4 NHL patients with less advance PTHRP concentrations sampled prior to cytotoxic chemotherapy, tumor response was associated with a decrease in PTHRP. Concomitant suppression of 1,25(OH)2D3 concentrations was observed in 66% of hypercalcemic patients with non-Hodgkin's lymphoma. CONCLUSIONS: These results suggest that PTHRP may be an important pathogenetic factor in the development of hypercalcemia in hematologic malignancies, notably in non-Hodgkin's lymphoma.


Assuntos
Biomarcadores Tumorais/sangue , Doença de Hodgkin/sangue , Linfoma não Hodgkin/sangue , Mieloma Múltiplo/sangue , Proteínas de Neoplasias/sangue , Hormônio Paratireóideo/sangue , Proteínas/análise , Macroglobulinemia de Waldenstrom/sangue , Antineoplásicos/uso terapêutico , Calcitriol/antagonistas & inibidores , Calcitriol/sangue , Cálcio/sangue , Estudos de Coortes , Feminino , Doença de Hodgkin/patologia , Humanos , Hipercalcemia/sangue , Hipercalcemia/etiologia , Linfoma não Hodgkin/tratamento farmacológico , Linfoma não Hodgkin/patologia , Masculino , Estadiamento de Neoplasias , Proteína Relacionada ao Hormônio Paratireóideo
10.
Obes Surg ; 9(1): 17-21, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10065575

RESUMO

BACKGROUND: Iron deficiency anemia is a common complication of gastric bypass. The authors assessed the value of taking vitamin C with oral iron in correcting deficiencies in iron stores and anemia postoperatively. MATERIALS AND METHODS: Iron absorption tests were performed on 55 patients 3.2+/-2.0 years after isolated gastric bypass to identify those at higher risk for the late development of anemia. Twenty-nine of this group agreed to a therapeutic trial of iron alone or with vitamin C over a 2-month period. All 55 patients were followed up for 27.1+/-1.0 months following the study. RESULTS: The iron absorption test identified patients with low iron stores, as indicated by low serum ferritin, and those with sufficient absorption surface to benefit from oral iron. The addition of vitamin C appears to enhance the therapeutic effect of iron by correcting ferritin deficits (P < 0.01) and anemia (P < 0.05). Differences in intestine length bypassed by the operation (10 vs. 100 cm) did not affect late ferritin and hemoglobin values. CONCLUSION: This study suggests but does not prove that the addition of vitamin C to iron therapy after gastric bypass is more effective in restoring ferritin and hemoglobin than iron alone. These results are in contrast with the outcome 22.8 months later, when approximately 50% of study patients were again anemic. Closer follow-up of patients is urgently needed.


Assuntos
Anemia Ferropriva/tratamento farmacológico , Ácido Ascórbico/administração & dosagem , Compostos Ferrosos/administração & dosagem , Derivação Gástrica/efeitos adversos , Ferro/sangue , Adulto , Anemia Ferropriva/sangue , Anemia Ferropriva/diagnóstico , Anemia Ferropriva/etiologia , Relação Dose-Resposta a Droga , Interações Medicamentosas , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
11.
Leuk Lymphoma ; 11(3-4): 165-71, 1993 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8260891

RESUMO

Although the spleen is frequently involved in disseminated non-Hodgkin's lymphoma (NHL), splenic presentation as the initial or only site of disease is uncommon. The true incidence of splenic lymphoma is difficult to estimate because of the variable definition of this disease, however, the diagnosis of primary lymphoma of the spleen should be limited to involvement of only the spleen and splenic hilum. Using this restricted definition, our experience suggests that the prognosis of NHL of the spleen, when pathologically staged, may have a favorable prognosis which approximates that seen with limited stage NHL at other sites. The influence of pathologic subtype on natural history and the impact of adjuvant therapy are discussed.


Assuntos
Linfoma/patologia , Neoplasias Esplênicas/patologia , Humanos , Linfoma/diagnóstico , Linfoma/mortalidade , Estadiamento de Neoplasias , Neoplasias Esplênicas/diagnóstico , Neoplasias Esplênicas/mortalidade , Taxa de Sobrevida , Tomografia Computadorizada por Raios X
12.
Cancer Control ; 5(3): 226-234, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-10761056

RESUMO

BACKGROUND: The role of interferon (IFN) in the treatment of multiple myeloma has been investigated for nearly two decades. The mechanisms underlying antitumor activity of IFN may be mediated by antiproliferative and immunomodulatory effects. The benefits of treatment remain controversial, and guidelines for the use of IFN in myeloma are needed. This review evaluates available data on the impact of IFN therapy on multiple myeloma. METHODS: A MEDLINE search of published prospective, randomized trials of IFN in multiple myeloma provided the data included in this review, as well as selected abstracts presented at international meetings. RESULTS: IFN has complex and pleiotropic effects on human myeloma lines and ex vivo myeloma cells. An antiproliferative effect with disruption of the IL-6-mediated growth loop may be crucial, but biologic heterogeneity in myeloma may have important clinical implications for response to IFN. IFN has demonstrable antitumor activity in multiple myeloma but appears to have a modest effect on overall survival when combined with chemotherapy during induction or when used as maintenance therapy. Most studies have shown a prolongation of the plateau phase of disease with IFN of variable duration of between four and 12 months. CONCLUSIONS: A reliable estimate of the benefit of IFN in the overall population of patients with myeloma is difficult to determine with discordant results from different trials. Possible sources of heterogeneity in randomized trials need to be identified, and recognition of subsets of patients who may benefit is important. Cost-benefit analyses with integration of quality-of-life data are essential for developing guidelines for the use of IFN in myeloma.

15.
Br J Dermatol ; 156(1): 57-61, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17199567

RESUMO

BACKGROUND: Patients with mycosis fungoides (MF) experience frequent disease recurrences following total skin electron irradiation (TSEI) and may benefit from adjuvant therapy. OBJECTIVES: To review the McGill experience with adjuvant alpha-interferon (IFN) in the treatment of MF. METHODS: From 1990 to 2000, 50 patients with MF were treated with TSEI: 31 with TSEI alone and 19 with TSEI + IFN. Median TSEI dose was 35 Gy. In the TSEI + IFN group, IFN was given subcutaneously at 3 x 10(6) units three times per week starting 2 weeks prior to start of TSEI, continued concurrently with the radiation and for an additional 12 months following TSEI. The TSEI alone group included 16 men and 15 women with a median age of 61 years (range 31-84). The TSEI + IFN group included 14 men and five women with a median age of 51 years (range 24-83). Clinical stage was IA, IB, IIA, IIB, III and IVA in 2, 9, 4, 8, 1 and 7 patients of the TSEI group and 0, 3, 3, 7, 4 and 2 patients of the TSEI + IFN group. RESULTS: Median follow up for living patients was 70 months. All patients responded to treatment. Complete response (CR) rate was 65% following TSEI and 58% following TSEI + IFN (P = 0.6). Median overall survival (OS) was 61 months following TSEI and 38 months following TSEI + IFN (P = 0.4). Acute grade II-III dermatitis was seen in all patients. Fever, chills or myalgia were seen in 32% of patients treated with TSEI + IFN. CONCLUSIONS: Concurrent IFN and TSEI is feasible, with acceptable toxicity. Even when controlling for disease stage, the addition of IFN did not appear to increase CR rate, disease-free survival or OS.


Assuntos
Antineoplásicos/uso terapêutico , Interferon Tipo I/uso terapêutico , Micose Fungoide/tratamento farmacológico , Micose Fungoide/radioterapia , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/radioterapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Quimioterapia Adjuvante/métodos , Estudos de Coortes , Terapia Combinada/métodos , Intervalo Livre de Doença , Toxidermias/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Proteínas Recombinantes , Estudos Retrospectivos , Resultado do Tratamento
17.
J Virol ; 67(8): 4722-31, 1993 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8392610

RESUMO

The Graffi murine leukemia virus (MuLV) is a retroviral mixture that induces predominantly myeloid leukemia in several inbred strains of mice. To analyze the viral component responsible for the myeloid leukemogenesis, we cloned several proviruses from a Graffi MuLV-infected cell line. Several infectious molecular clones were obtained that could be classified into two distinct groups of infectious MuLV. Both types of MuLV were nondefective, ecotropic, and NB tropic and induced granulocytic leukemia in BALB/c and NFS mice. Restriction enzyme analysis and molecular hybridization with several MuLV probes on one molecular clone from each group revealed that both groups are closely related to each other but are clearly distinct from all known retroviruses. One component of MuLV, however, induced leukemia with a shorter latency period and harbored a lengthier long terminal repeat. The long terminal repeat of the more leukemogenic component of MuLV had acquired a 60-bp perfect duplication in the U3 region. Analysis of the tumor DNAs with probes for the mouse T-cell receptor and immunoglobulin heavy chain genes revealed frequent rearrangements with one or both probes. This concomitant expression by leukemic cells of markers of different lineages, observed in human leukemias, has been termed "lineage infidelity" and confirms that the latter rearrangements are not restricted to hematopoietic precursors committed to lymphoid differentiation.


Assuntos
Vírus da Leucemia Murina/genética , Leucemia Experimental/microbiologia , Leucemia Mieloide/microbiologia , Animais , Sequência de Bases , Southern Blotting , Linhagem Celular , Clonagem Molecular , Sondas de DNA , DNA Viral/genética , DNA Viral/isolamento & purificação , Genes de Imunoglobulinas , Vírus da Leucemia Murina/patogenicidade , Leucemia Experimental/fisiopatologia , Leucemia Mieloide/fisiopatologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos , Dados de Sequência Molecular , Regiões Promotoras Genéticas , Receptores de Antígenos de Linfócitos T/genética , Sequências Repetitivas de Ácido Nucleico , Mapeamento por Restrição
18.
Br J Haematol ; 79(1): 50-6, 1991 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1911388

RESUMO

Multidrug resistance (MDR) in cultured human cells is caused by the overexpression of the MDR-1 gene. This gene codes for P-glycoprotein, a proposed ATP-dependent drug efflux pump, which reduces the net intracellular accumulation of a large group of chemotherapeutic agents in resistant cells. We have measured the level of expression of the human MDR-1 gene in a series of patients with chronic lymphocytic leukaemia (CLL). Forty-eight patients included in the study were at different stages of disease and were either untreated or had been treated with alkylating agents or alkylating agents in combination with drugs of the MDR spectrum, and were tested over a period of 3 years. The level of MDR-1 expression was monitored by Northern blotting analysis using a specific cDNA hybridization probe and also after polymerase chain reaction (PCR) amplification of MDR-1 complementary DNA (cDNA). Four of 28 previously untreated patients showed intrinsically high levels of MDR-1 mRNA while 5/19 treated patients had elevated MDR-1 expression. Elevated MDR-1 expression in treated patients was unrelated to the type of chemotherapy and was independent of previous exposure to drugs of the MDR spectrum. Intrinsic MDR-1 gene expression in positive patients did not appear to influence their response to chemotherapy with non-MDR drugs such as alkylating agents.


Assuntos
Resistência a Medicamentos/genética , Expressão Gênica/fisiologia , Leucemia Linfocítica Crônica de Células B/genética , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Northern Blotting , Clorambucila/uso terapêutico , Expressão Gênica/efeitos dos fármacos , Humanos , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Reação em Cadeia da Polimerase
19.
Acta Haematol ; 80(3): 153-8, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-2973720

RESUMO

In evaluating hypoimmunoglobulinemia in a patient with nonsecretory myeloma, studies of in vitro immunoglobulin synthesis were performed during a 3-year period. Impaired polyclonal response to mitogen stimulation associated with excessive suppressor activity was demonstrable at diagnosis. Despite successful chemotherapy, serum immunoglobulin levels remained depressed with a persistent impairment in polyclonal immunoglobulin synthesis but without evidence for excessive suppression. In nonsecretory myeloma, as in secretory myeloma, a defective B-cell response to differentiation signals may be a contributory mechanism in the hypoimmunoglobulinemia seen in this disease.


Assuntos
Agamaglobulinemia/imunologia , Plasmocitoma/imunologia , Agamaglobulinemia/patologia , Medula Óssea/patologia , Medula Óssea/ultraestrutura , Imunofluorescência , Humanos , Imunoglobulina G/biossíntese , Imunoglobulina M/biossíntese , Masculino , Pessoa de Meia-Idade , Plasmocitoma/ultraestrutura , Linfócitos T Reguladores/imunologia
20.
Cell Immunol ; 103(2): 352-64, 1986 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2433052

RESUMO

The activity of natural killer (NK) cells can be augmented by incubation with interferons, or with other compounds, such as staphylococcal protein A, which stimulate interferon production. In the experiments described here we compared the patterns of lytic activity of human lymphoid effector cells, before (NK-B) and after (NK-A) short-term activation. Target cells used were K562, Clone I (a partially NK-resistant K562 variant), and those that had been preincubated with neuraminidase or trypsin. The results obtained include the following: proteases, but not neuraminidase, decreased lysis by NK-B, but not by NK-A, of both K562 and Clone I in the standard Cr-release assay. In the single cell assay, trypsin minimally decreased conjugate formation and the fraction of bound cells that were killed by NK-B, but did not reverse the increased lytic efficiency of NK-A. In the cold-target competition assay, Clone I, which does not compete as well with K562 for NK-B, did so equally well for NK-A. Trypsinized targets, regardless of their equal sensitivity to lysis by NK-A, were not as active competitors for NK-A. We conclude that the most reasonable interpretation is that K562 cells bear surface structures which can induce release of lytic mediators from NK-A under conditions that are not sufficient to stimulate NK-B. Although it appears that NK-A may respond to a smaller number of the same target molecules recognized by NK-B, the process must be better defined at the molecular level to exclude the possibility that there are qualitative differences between the proposed recognition structures for these two states of NK activity.


Assuntos
Células Matadoras Naturais/imunologia , Ativação Linfocitária , Linhagem Celular , Quimotripsina/farmacologia , Proteínas do Sistema Complemento/imunologia , Citotoxicidade Imunológica , Humanos , Interferons/farmacologia , Neuraminidase/farmacologia , Tripsina/farmacologia
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