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1.
Cancer Res ; 51(2): 536-41, 1991 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-1985771

RESUMO

The process of cellular iron uptake involves a specific receptor for the plasma carrier transferrin and a pathway of receptor-mediated endocytosis. Transferrin receptor expression is closely related to the rate of cell proliferation, and conjugates between anti-transferrin receptor monoclonal antibodies and toxins have been shown to have potent cytotoxic activity. We have constructed an anti-transferrin receptor immunotoxin by conjugating the anti-transferrin receptor monoclonal antibody B3/25 to a ribosome-inactivating protein, the saporin-6 (SO6), which is derived from the seeds of the plant Saponaria officinalis. The immunotoxin B3/25-SO6 was tested for in vitro cytotoxic activity against the human cell lines K-562 and HL-60 and against normal human bone marrow hematopoietic progenitors and acute myeloid leukemia clonogenic cells. The immunotoxin proved to be an effective inhibitor of K-562 and HL-60 clonogenic cell growth, in vitro colony formation being completely inhibited at immunotoxin concentrations ranging from 10(-7) to 10(-10) M. B3/25-SO6 markedly reduced the recloning efficiency of HL-60 clonogenic cells at 10(-12) M. Exposure of HL-60 cells in suspension culture to 10(-9) M B3/25-SO6 for 48-72 h completely abolished their clonogenic potential. The immunotoxin was also found to be cytotoxic against normal human bone marrow progenitor cells (burst-forming unit-erythroid and colony-forming unit-granulocyte, macrophage) in a dose-dependent manner. However, exposure of normal colony-forming unit-granulocyte, macrophage in suspension culture to 10(-9) M B3/25-SO6 for 72 h resulted in only 50% suppression of their clonogenic potential. Finally, B3/25-SO6 was found to be a potent inhibitor of in vitro growth of acute myeloid leukemia clonogenic cells. The cytotoxic effects of B3/25-SO6 were shown to be specific, since both saporin alone and irrelevant immunotoxins did not have any effect in the cellular systems examined. We conclude that the immunotoxin B3/25-SO6 has dose-related cytotoxic effects on both normal and leukemic human hematopoietic progenitors. Since there are substantial differences between normal and leukemic progenitors with respect to the proportion of cycling cells and the expression of transferrin receptors, B3/25-SO6 or similar immunotoxins may have clinical application in bone marrow-purging procedures.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Células-Tronco Hematopoéticas/citologia , Imunotoxinas/farmacologia , N-Glicosil Hidrolases , Proteínas de Plantas/farmacologia , Receptores da Transferrina/imunologia , Anticorpos Monoclonais/farmacologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Células Clonais , Ensaio de Unidades Formadoras de Colônias , Células-Tronco Hematopoéticas/efeitos dos fármacos , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva , Leucemia Promielocítica Aguda , Proteínas Inativadoras de Ribossomos Tipo 1 , Saporinas , Ensaio Tumoral de Célula-Tronco
2.
Leukemia ; 6(1): 1-7, 1992 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1736009

RESUMO

By using antisense oligomers the functional role of the c-abl proto-oncogene in the in vitro growth of bone marrow hematopoietic progenitors from normal subjects and patients with chronic myelogenous leukemia (CML) has been evaluated. Light density bone marrow cells (LDBMs) were depleted of adherent cells, pre-incubated for 15 h with the appropriate oligomer at a concentration of 14 microns, and then plated in methylcellulose for the evaluation of colony formation. Both anti-exon Ia and anti-exon Ib antisense oligomers produced a significant inhibition of normal day 14 CFU-GM growth in vitro (n = 5, 41 +/- 11%, and 36 +/- 7%, respectively; p less than 0.01). In contrast, normal BFU-E growth was not significantly influenced by antisense oligomers (n = 5, 14 +/- 21% and 7 +/- 19%, respectively; p less than 0.05). These findings were confirmed by plating CD34 positive progenitors. When interleukin 3 (IL-3) (100 ng/ml) was added to the culture medium during the preincubation of LDBMCs, the inhibitory effects of antisense oligomers on normal CFU-GM growth were abolished. Seven patients with CML were also studied, all of whom had cytogenetic evidence of 100% clonal hematopoiesis. In five patients in the chronic phase, antisense oligomers were inhibitory on in vitro growth of both day 14 CFU-GM (37 +/- 20% and 37 +/- 15%, p less than 0.05) and BFU-E (45 +/- 15% and 41 +/- 11%, p less than 0.05), and this inhibition was not removed by pre-incubation with IL-3. No significant effect was observed on cluster or colony formation in two patients with CML in accelerated or blastic phase, and on in vitro growth of clonogenic cells from the Ph1-positive K-562 cell line. These findings (i) confirm previous observations showing a lineage specific requirement of c-abl function in normal hematopoiesis, and (ii) suggest that the residual c-abl expression has a role in chronic phase CML hematopoiesis, as its inhibition impairs both myeloid and erythroid colony formation in vitro.


Assuntos
Regulação Leucêmica da Expressão Gênica/fisiologia , Genes abl/fisiologia , Hematopoese/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Oligonucleotídeos Antissenso , Ensaio Tumoral de Célula-Tronco , Sequência de Bases , Crise Blástica/genética , Medula Óssea/patologia , Eritrócitos , Granulócitos , Hematopoese/efeitos dos fármacos , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Dados de Sequência Molecular , Proto-Oncogene Mas
3.
Leukemia ; 7(12): 2012-8, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8255101

RESUMO

Experimental evidence suggests that hematopoietic growth factors promote cell survival by suppressing apoptosis or programmed cell death. Since interleukin 3 (IL-3) and granulocyte-macrophage colony stimulating factor (GM-CSF) induce tyrosine phosphorylation of a common set of proteins in the factor-dependent cell line M07e, we have investigated whether growth-factor-induced tyrosine phosphorylation is involved in the promotion of cell survival and suppression of apoptosis. Experiments were carried out with the leukemic cell lines HL-60 and M07e and the tyrosine kinase inhibitors genistein and tyrphostin AG82. Both the tyrosine kinase inhibitors induced apoptosis of HL-60 and M07e cells. This was indicated by the appearance of DNA degradation and morphologic evidence of nuclear condensation and fragmentation. It was also confirmed by flow cytometry of DNA, which showed apoptotic cells as a fraction of cells characterized by a diminished DNA stainability, represented on the DNA frequency histograms as a distinct peak below the G0/G1 population. Kinase inhibitors also reduced the fraction of cells in the S phase of the cell cycle. That tyrphostin specifically inhibited tyrosine kinases was further suggested by the prevention of its effects by the tyrosine phosphatase inhibitor sodium orthovanadate (vanadate), at least during the first 18-24 h of treatment. The incomplete prevention of genistein effects by vanadate suggests that genistein is a less specific inhibitor of tyrosine kinases than tyrphostin, and may also act as an inhibitor of topoisomerase II. Vanadate also prevented apoptosis and reduction of the S phase in M07e cells cultured for 24 h in the absence of growth factors. These results suggest that tyrosine phosphorylation is an essential step in IL-3 and GM-CSF signal transduction. Since in our experimental model the effects of tyrosine kinase inhibition and growth factor deprivation could be reversed by concomitant inhibition of tyrosine phosphatases, it is suggested that a balance between tyrosine kinases and tyrosine phosphatases establishes whether a cell will survive or undergo apoptosis.


Assuntos
Catecóis/farmacologia , Isoflavonas/farmacologia , Leucemia Megacarioblástica Aguda/patologia , Leucemia Promielocítica Aguda/patologia , Nitrilas/farmacologia , Proteínas Tirosina Quinases/antagonistas & inibidores , Tirosina/metabolismo , Tirfostinas , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Citometria de Fluxo , Genisteína , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Humanos , Interleucina-3/farmacologia , Leucemia Megacarioblástica Aguda/enzimologia , Leucemia Megacarioblástica Aguda/metabolismo , Leucemia Promielocítica Aguda/enzimologia , Leucemia Promielocítica Aguda/metabolismo , Fosforilação , Proteínas Tirosina Fosfatases/fisiologia , Proteínas Tirosina Quinases/fisiologia , Células Tumorais Cultivadas/efeitos dos fármacos , Células Tumorais Cultivadas/metabolismo , Células Tumorais Cultivadas/patologia , Vanadatos/farmacologia
4.
Leukemia ; 3(5): 363-6, 1989 May.
Artigo em Inglês | MEDLINE | ID: mdl-2654496

RESUMO

The in vitro effect of recombinant human GM-CSF (rHuGM-CSF) was tested on bone marrow-derived multilineage (CFU-GEMM) as well as megakaryocytic (CFU-Mk), erythroid (BFU-E), and granulocyte-macrophage (CFU-GM) progenitors in a group (n = 16) of patients with myelodysplastic syndromes (MDS). Hematopoietic progenitor cell growth was markedly impaired in MDS patients as compared to normal controls (p less than 0.05, at least). Recombinant HuGM-CSF supported the growth of CFU-GEMM, CFU-Mk, and BFU-E at lower, equivalent, or slightly higher frequencies that those found in cultures plated with medium conditioned by peripheral blood leukocytes (PHA-LCM), but it was invariably ineffective in improving growth values. Recombinant HuGM-CSF supported the growth of granulocyte-macrophage colonies in 15 of 16 cases. The overall incidence (mean +/- SEM) of CFU-GM in cultures containing rHuGM-CSF (5 ng/ml) was significantly higher than the one found in cultures stimulated with PHA-LCM (40 +/- 15 vs. 17 +/- 7, p less than 0.05). Upon culture with rHuGM-CSF (5 ng/ml), in 5 of 15 patients de novo colony formation was observed (8 +/- 4) and in 4 of 15 patients CFU-GM growth (129 +/- 33) fell within normal range. Doses of rHuGM-CSF higher than 5 ng/ml did not result in a further increase of MDS-derived colony formation. It is concluded that rHuGM-CSF (a) does not improve the growth of CFU-GEMM, CFU-Mk, and BFU-E; (b) may completely restore the growth of CFU-GM in a subgroup of MDS patients; (c) while ineffective in improving anemia and thrombocytopenia, its in vivo in MDS may correct leukopenia through an effect at the level of granulocyte-macrophage progenitor cell compartment, at least in a subset of highly responsive patients.


Assuntos
Fatores Estimuladores de Colônias/farmacologia , Substâncias de Crescimento/farmacologia , Células-Tronco Hematopoéticas/efeitos dos fármacos , Síndromes Mielodisplásicas/patologia , Adulto , Idoso , Divisão Celular/efeitos dos fármacos , Feminino , Fator Estimulador de Colônias de Granulócitos e Macrófagos , Humanos , Técnicas In Vitro , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes/farmacologia
5.
Leukemia ; 5(10): 886-91, 1991 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1961022

RESUMO

Tumor necrosis factor alpha (TNF-alpha) has been previously shown to modulate the expression of hematopoietic growth factor genes in monocytes and other mesenchymal cells. As acute myeloblastic leukemia (AML) blasts can express and produce hematopoietic growth factors, the influence of TNF-alpha on the accumulation of mRNAs for c-myc, interleukin-3 (IL-3), granulocyte-macrophage colony-stimulating factor (GM-CSF), G-CSF, IL-6 and IL-1 beta was evaluated in fresh blasts from 13 patients with AML. Total cellular RNA was extracted from blast cells cultured for 24 hours with or without TNF-alpha (500 U/ml). The c-myc transcript level was decreased by TNF-alpha treatment in 9/13 cases, and increased in only one case. Among the growth factor genes, the GM-CSF gene was more often and consistently influenced by TNF-alpha, increased levels of its transcript being observed in 6/13 cases following treatment with the cytokine; in no case was there a reduction of GM-CSF mRNA. G-CSF and IL-6 transcripts were more heterogeneously influenced, whereas the IL-3 transcript was never detected in our AML samples. The IL-1 beta message was present in 8/13 untreated and in 13/13 TNF-alpha treated samples. Moreover, in untreated cells, GM-CSF, G-CSF and IL-6 expression was always associated with IL-beta expression. These findings indicate that TNF-alpha can modulate the levels of growth factor transcripts in AML blasts, and raise questions about the effects of TNF-alpha on leukemic hematopoiesis, considering that TNF-alpha, IL-1 and GM-CSF can synergistically stimulate the growth of AML clonogenic cells.


Assuntos
Fatores de Crescimento de Células Hematopoéticas/genética , Leucemia Mieloide Aguda/genética , RNA Mensageiro/genética , Fator de Necrose Tumoral alfa/farmacologia , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Genes myc/efeitos dos fármacos , Genes myc/genética , Fator Estimulador de Colônias de Granulócitos e Macrófagos/genética , Fatores de Crescimento de Células Hematopoéticas/metabolismo , Humanos , Interleucina-1/genética , Interleucina-3/genética , Interleucina-6/genética , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/metabolismo , RNA Mensageiro/metabolismo , RNA Neoplásico/metabolismo , Transcrição Gênica , Células Tumorais Cultivadas/efeitos dos fármacos
6.
Leukemia ; 2(1): 55-9, 1988 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3123808

RESUMO

gamma-Interferon (IFN-gamma) has previously been found to induce monocytic differentiation in established leukemic cell lines, such as HL-60 and U937. The aim of the present study was to evaluate the differentiative effect of highly purified recombinant (r)IFN-gamma on fresh bone marrow cells from patients with acute nonlymphocytic leukemia (n = 11) or myelodysplastic syndromes (n = 3). Blast cells were cultured in suspension in the presence or absence of rIFN-gamma (10-10(3) U/ml). While 6 out of 14 cases were unresponsive to rIFN-gamma in vitro, the remaining 8 patients showed a significant increase (0.05 greater than p greater than 0.001) in the percentage of cells expressing C3bi receptors, detected by OKM1 (median value in control cell, 9.5; median value in rIFN-gamma-treated cells, 31) and Mo1 (8.5 vs. 36), and in the percentage of cells expressing the monocytic antigens detected by Mo2 (8 vs. 28) and MY4 (6.5 vs. 32.5). In the responsive patients morphologic changes consistent with monocytic maturation, as well as a strong increase of alpha-naphthyl acetate esterase activity and of nitroblue tetrazolium reducing capability were observed upon culture with rIFN-gamma. We conclude that (a) rIFN-gamma may induce in vitro monocytic differentiation of blasts from acute nonlymphocytic leukemia and myelodysplastic syndrome patients, and that (b) this agent should be investigated for its capacity to be active in vivo.


Assuntos
Interferon gama/farmacologia , Leucemia/patologia , Monócitos/citologia , Síndromes Mielodisplásicas/patologia , Proteínas Recombinantes/farmacologia , Doença Aguda , Antígenos de Neoplasias/imunologia , Antígenos de Superfície/imunologia , Medula Óssea/imunologia , Medula Óssea/patologia , Diferenciação Celular/efeitos dos fármacos , Sobrevivência Celular , Humanos , Interferon gama/biossíntese , Leucemia/imunologia , Síndromes Mielodisplásicas/imunologia , Células Tumorais Cultivadas
7.
Leukemia ; 4(6): 426-30, 1990 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2359342

RESUMO

We have studied tumor necrosis factor alpha (TNF-alpha) for its capacity to induce differentiation and to modulate c-myc and c-fms protooncogene mRNA expression in fresh blasts from 10 patients with acute myeloblastic leukemia (AML). Bone marrow blast cells were grown in suspension cultures in the presence of 500 U/ml (62 ng/ml) of TNF-alpha for 7 days. Induction of differentiation was assessed by means of morphology, cytochemistry, immunophenotyping (CD11b, CD13, CD14, CD33), and nitroblue tetrazolium reduction. In all cases, exposure of leukemic blasts to TNF-alpha resulted in phenotypic changes consistent with induction of differentiation, although a marked variability in degree and type of response was observed. The majority of cases developed monocytic morphology and showed significant increases (chi 2 test, p less than 0.05) in phagocytic activity and/or expression of ANAE and myelomonocytic differentiation antigens (CD11b, CD14). TNF-alpha reduced c-myc mRNA level over a period of 24 hr in four of six cases studied: the two cases with no down-regulation were the least responsive in terms of myelomonocytic differentiation. These results confirm those obtained with leukemic cell lines, suggesting that TNF-alpha can induce differentiation of fresh AML blasts, mainly toward the monocytic lineage, and that induction of differentiation seems to be closely linked to down-regulation of c-myc mRNA expression over the first 24 hr rather than to attenuation of cellular proliferation per se.


Assuntos
Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , Leucemia Mieloide Aguda/genética , Monócitos/patologia , Proto-Oncogenes , RNA Mensageiro/genética , Fator de Necrose Tumoral alfa/farmacologia , Medula Óssea/patologia , Diferenciação Celular , Distribuição de Qui-Quadrado , Humanos , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , RNA Mensageiro/metabolismo , Células Tumorais Cultivadas/metabolismo , Células Tumorais Cultivadas/patologia
8.
Leukemia ; 3(2): 104-7, 1989 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2911202

RESUMO

The iron chelator desferrioxamine (DFO) has been previously shown to be an S-phase inhibitor of cell proliferation. To investigate its potential as an antileukemic drug, we first studied the effects of DFO on the in vitro growth of normal human hematopoietic progenitors (CFU-GM and BFU-E) and clonogenic cells from human leukemic cell lines. Then we evaluated the effects of DFO on progression of leukemia refractory to conventional therapy in two individuals. Micromolar concentrations of DFO determined a dose-dependent inhibition of normal progenitor growth, with inhibitory dose 50% (ID50) for CFU-GM and BFU-E being 6.7 and 5.5 microM/liter, respectively. Marked inhibitory effects were observed on clonogenic cells from HL-60 (ID50 = 1.4 microM/liter) and U-937 (ID50 = 3.6 microM/liter) human leukemic cell lines grown in semisolid medium. When DFO was given intravenously to a patient with lymphoid blast crisis of chronic myelogenous leukemia, a marked reduction in circulating blast count was observed. On the contrary, no in vivo effect was observed in a patient with acute nonlymphocytic leukemia having transfusional iron overload. We conclude that: (a) DFO is an inhibitor of both normal and leukemic myeloid cell proliferation in vitro; (b) our limited in vivo observations and a previous case study suggest that intravenous administration of DFO to patients with normal to low plasma iron may result in leukemic cytoreduction in vivo.


Assuntos
Desferroxamina/farmacologia , Desferroxamina/uso terapêutico , Células-Tronco Hematopoéticas/citologia , Células-Tronco Neoplásicas/citologia , Anemia Refratária com Excesso de Blastos/tratamento farmacológico , Crise Blástica , Divisão Celular/efeitos dos fármacos , Ensaio de Unidades Formadoras de Colônias , Humanos , Técnicas In Vitro , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico
9.
Exp Hematol ; 21(1): 70-3, 1993 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7678089

RESUMO

The aim of the present study was to evaluate whether the erythropoietic response to hemolysis can be mediated by other regulatory peptides in addition to erythropoietin. For this purpose, we have investigated the influence of erythrophagocytosis by human monocytes and macrophages on the mRNA expression of several growth factor genes, including interleukin-3 (IL-3), granulocyte/macrophage colony-stimulating factor (GM-CSF) and erythroid potentiating activity (EPA), which are supposed to influence erythropoiesis. Immunologically mediated erythrophagocytosis increased the expression of EPA mRNA (2 to 3 times). Such increase appeared to be specifically associated with phagocytosis of erythrocytes, since phagocytosis of yeast microorganisms or antibody-coated latex particles had no effect on EPA gene expression. Yeast, however, powerfully stimulated the expression of GM-CSF, granulocyte colony-stimulating factor (G-CSF) and interleukin-6 (IL-6) mRNAs which, with the exception of G-CSF, were not influenced by erythrophagocytosis. Erythropoietin and IL-3 mRNAs were never detected in cultured monocytes, either in control or in treated samples. Our findings may suggest that phagocytosis of erythrocytes by monocytes/macrophages increases the expression, and possibly the production, of EPA. This could in turn potentiate the erythropoietic response to extravascular hemolysis by increasing the number of cells responsive to erythropoietin. Thus, EPA might be a mediator of an end-product positive feedback on the rate of red cell production.


Assuntos
Eritrócitos , Linfocinas/genética , Macrófagos/fisiologia , Monócitos/fisiologia , Fagocitose/fisiologia , RNA Mensageiro/sangue , Células Cultivadas , Eritropoese/fisiologia , Expressão Gênica , Fator Estimulador de Colônias de Granulócitos/genética , Fator Estimulador de Colônias de Granulócitos e Macrófagos/genética , Humanos , Interleucina-3/genética , Interleucina-6/genética , Saccharomyces cerevisiae , Inibidores Teciduais de Metaloproteinases
10.
Hematol J ; 2(1): 26-32, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11920230

RESUMO

INTRODUCTION: Normal immature hematopoietic progenitors are relatively well preserved in most patients newly diagnosed with chronic myeloid leukemia, but tend to decline rapidly with time. Such exhaustion could reflect a suppressive effect of the Philadelphia positive clone expansion and/or be induced by Interferon-alpha treatment. MATERIALS AND METHODS: A total of 51 CML patients were classified into three groups. Newly diagnosed untreated patients were group A (n=30). Of the 21 treated individuals with Interferon-alpha, for at least 12 months, 15 showed no cytogenetic response (group B) while six showed persisting major/complete response (group C). Patients belonging to groups A and B were mobilized with chemotherapy plus G-CSF while patients of group C received a short course of G-CSF only. RESULTS: Patients responding to IFN-alpha (group C) showed comparable numbers of bone marrow Ph- long-term culture initiating cells to those of newly diagnosed individuals (group A): 8.5 (<1-65)/10(6) MNC vs 10.5 (<1-30), while non-responders had markedly lower numbers: <1 (<1-5). The amount of Ph- LTC-IC collected was significantly lower in patients of group B 1.8 (0-325)x10(2)/kg than in patients of either group A 31.3 (0-952)x10(2)/kg (P<0.002) or group C 109 (8-259)x10(2)/kg (P<0.01). Interestingly, five patients of group B who had 100% Ph+ metaphases, but Ph- progenitors in their bone marrow, mobilized normal amounts of Ph(-) progenitors. CONCLUSION: These findings suggest that the decline of normal hematopoietic progenitors, currently observed in the majority of CML patients, is not induced by IFN-alpha treatment, but it is likely due to the expanding leukemic clone. They also indicate that normal hematopoietic reservoir is consistently preserved in patients given IFN-alpha early after diagnosis and achieving a stable cytogenetic response.


Assuntos
Interferon-alfa/farmacologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Cromossomo Filadélfia , Células-Tronco/efeitos dos fármacos , Adulto , Células da Medula Óssea/efeitos dos fármacos , Estudos de Casos e Controles , Contagem de Células , Análise Citogenética , Feminino , Fator Estimulador de Colônias de Granulócitos/administração & dosagem , Fator Estimulador de Colônias de Granulócitos/farmacologia , Humanos , Interferon-alfa/administração & dosagem , Leucaférese , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Leucócitos Mononucleares/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/patologia
11.
Leuk Lymphoma ; 18 Suppl 1: 57-60, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7496356

RESUMO

In the hypergranular group of acute promyelocytic leukemia (APL) a rare subvariant with basophilic granules, metachromatic for toluidine blue, is recognizable. To evaluate the incidence as well as the biological and clinical significance of this subtype, we studied 53 consecutive untreated patients with APL with morphological, cytochemical, immunological and cytogenetic methods. In 10 cases (19% of the total) granules stained metachromatically in percentages of promyelocytes ranging from 16 to 60. In these cases peroxidase positivity was weaker than in the classic hypergranular and microgranular M3 and activities of esterases were usually present; at the ultrastructural level granules contained particulate material. Immunophenotypic and cytogenetic characteristics seemed not to differ from those of other M3 cases. Coagulopathy was usually life-threatening, notwithstanding the low white cell count, and the median survival was short. Hyperhistaminemia-related symptoms were not observed. Cytochemical, immunologic and cytogenetic findings are useful to differentiate this form from M2 with basophilic differentiation and from mast cell leukemia.


Assuntos
Leucemia Promielocítica Aguda/diagnóstico , Grânulos Citoplasmáticos/ultraestrutura , Humanos , Leucemia Promielocítica Aguda/classificação , Leucemia Promielocítica Aguda/patologia , Microscopia Eletrônica , Cloreto de Tolônio
12.
Toxicology ; 130(1): 29-41, 1998 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-9846994

RESUMO

Omeprazole, a proton pump inhibitor of wide use in the treatment of gastric acid-related disorders, was evaluated for its genotoxic effects in both rat and human cultured cells and in the intact rat. DNA repair synthesis, as revealed by autoradiography, was detected in primary cultures of metabolically competent rat hepatocytes exposed to concentrations ranging from 10 to 100 mg/l, but the responses cannot be considered as clearly positive. Under the same experimental conditions any significant evidence of DNA repair was absent in primary hepatocytes from two human donors. At the same concentrations a modest but dose-related increase of micronucleated cells, that reached the level of statistical significance at 33 mg/l, was present in primary rat hepatocytes and in one of two human donors. In human lymphocytes exposed to subtoxic concentrations ranging from 0.78 to 12.5 mg/l a reproducible concentration dependent clastogenic effect was absent. In partially hepatectomized female rats treated with a single p.o. dose of 1000 mg/kg, the frequency of micronucleated cells was 5.2-fold higher than in controls in the liver, but only 2.0-fold higher in polychromatic erythrocytes of the bone marrow. In rats of the same sex given azoxymethane as initiator of colon carcinogenesis the oral administration for 8 successive weeks of 10 mg/kg omeprazole on alternate days increased the response to azoxymethane, as indicated by the occurrence in colon mucosa of a modest but statistically significant increase in both the average number and size of aberrant crypt foci. Taken as a whole, our results suggest that omeprazole behaves as a weak genotoxic agent for the rat liver. Reliable information about the potential genotoxic risk to humans requires further studies on primary cells from a wide number of donors.


Assuntos
Antiulcerosos/toxicidade , Colo/efeitos dos fármacos , Fígado/efeitos dos fármacos , Testes de Mutagenicidade , Omeprazol/toxicidade , Adulto , Idoso , Animais , Células Cultivadas , Colo/enzimologia , Reparo do DNA/efeitos dos fármacos , Feminino , Humanos , Fígado/enzimologia , Linfócitos/efeitos dos fármacos , Masculino , Testes para Micronúcleos , Ratos , Ratos Sprague-Dawley
13.
Anticancer Res ; 12(3): 853-61, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1320358

RESUMO

We established and characterized two cell lines derived from glioblastoma multiforme. Both cell lines exhibited tumor cell morphology and growth kinetics and showed variable expression of glial fibrillary acidic protein (GFAP), S-100, fibronectin and vimentin. Cytofluorimetrical analysis of tumor samples showed a diploid DNA distribution, whereas permanent culture cells evolved to the hyperdiploid DNA content. Karyotype studies revealed cytogenetical abnormalities described in glial tumors including gain of chromosome 7, loss of chromosome 10 and presence of double minutes (DMs). Enhanced expression of Ha-ras and c-myc genes resulted from high p-21 and p-62 levels. The contemporary presence of TGF-alpha and EGF-Rc transcripts suggested an autocrine mechanism in the cell lines growth.


Assuntos
Aberrações Cromossômicas , Transtornos Cromossômicos , Glioblastoma/patologia , Divisão Celular , Linhagem Celular , Bandeamento Cromossômico , Deleção Cromossômica , Cromossomos Humanos Par 7 , Técnicas de Cultura/métodos , DNA de Neoplasias/análise , Diploide , Receptores ErbB/genética , Genes myc , Genes ras , Proteína Glial Fibrilar Ácida/análise , Glioblastoma/genética , Humanos , Cariotipagem , Cinética , Ploidias , Transcrição Gênica , Fator de Crescimento Transformador alfa/genética
14.
J Inorg Biochem ; 68(4): 295-305, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9397578

RESUMO

A series of organotin complexes with pyrrole-2-carboxaldehyde 2-hydroxybenzoylhydrazone (H3mfps) and pyrrole-2-carboxaldehyde 2-picolinoylhydrazone (H2mfpp) was investigated. The IR, 1H, and 119Sn nuclear magnetic resonance spectroscopic characterization of all the compounds is reported and discussed in connection with the ligand behaviour of the hydrazone and the structure of the organotin complex. Complexes exhibit antibacterial properties higher than those of the corresponding ligands but they turn out to be less potent than the parent organotin compounds. Sn(H3mfps) (C6H5)2Cl2.2H2O and Sn(Hmfpp)(n-C4H9)2Cl are the most active antibacterial compounds showing MIC values between 3-6 micrograms/ml against Bacillus subtilis and Staphylococcus aureus and between 6-25 micrograms/ml against Escherichia coli; the first compound also strongly inhibits the growth of Aspergillus niger. All the ligands and complexes are devoid of DNA-damaging activity in the Bacillus subtilis rec-assay. H2mfpp and its complexes Sn(Hmfpp)(C2H5)2Cl and Sn3(Hmfpp)(mfpp) (C6H5)3Cl6 are shown by the Salmonella-microsome assay to be mutagenic substances in the presence of a metabolic activation system. The obtained results are discussed on the basis of structure-activity relationships.


Assuntos
Bactérias/efeitos dos fármacos , Hidrazonas/síntese química , Mutagênicos , Compostos Orgânicos de Estanho/síntese química , Pirróis/síntese química , Aspergillus niger/efeitos dos fármacos , Bacillus subtilis/efeitos dos fármacos , Bacillus subtilis/genética , Candida/efeitos dos fármacos , Dano ao DNA , Eletroquímica , Escherichia coli/efeitos dos fármacos , Fungicidas Industriais , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Hidrazonas/química , Hidrazonas/farmacologia , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Compostos Orgânicos de Estanho/química , Compostos Orgânicos de Estanho/farmacologia , Pirróis/química , Pirróis/farmacologia , Salmonella typhimurium/efeitos dos fármacos , Software , Staphylococcus aureus/efeitos dos fármacos , Relação Estrutura-Atividade
15.
Eur J Clin Nutr ; 57(4): 566-72, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12700618

RESUMO

OBJECTIVES: (a). to explore the relationship between waist circumference and certain cardiovascular risk factors in a group of girls; and (b). to assess the clinical relevance of waist circumference in identifying girls with higher cardiovascular risk across puberty. SUBJECTS AND METHODS: One-hundred and fifty-five overweight or obese girls aged 5-16 y were recruited. Overweight and obesity were defined on the basis of BMI, according to Cole. RESULTS: : Waist circumference was significantly correlated with plasma insulin (r=0.43; P<0.001), systolic blood pressure (r=0.22; P=0.007) and IR(HOMA) (r=0.40; P<0.001). A multivariate linear correlation analysis showed that, when adjusted for age and Tanner stage, waist circumference was significantly associated with plasma insulin (r(2)=0.23; P<0.01), IR(HOMA) (r(2)=0.17; P<0.02), systolic and diastolic blood pressure (r(2)=0.20; P=0.006 and r(2)=0.32; P<0.001, respectively). A logistic regression analysis, using IR(HOMA) as the dependent variable, showed that waist circumference was a significant independent risk factor of insulin resistance (IR(HOMA)>or=2.6) in this group of girls (OR 1.10; 95% CI 1.03-1.18; P=0.003), independently of their age and Tanner stage. CONCLUSIONS: Waist circumference of these girls was independently associated with certain cardiovascular risk factors, in particular insulin resistance and diastolic blood pressure, independently of age and Tanner stage. Thus suggesting that waist circumference may be reasonably included in clinical practice as a simple tool that may help to identify sub-groups of obese girls at higher metabolic risk across puberty.


Assuntos
Constituição Corporal , Doenças Cardiovasculares/etiologia , Obesidade/complicações , Adolescente , Pressão Sanguínea , Índice de Massa Corporal , Criança , Pré-Escolar , Feminino , Humanos , Insulina/sangue , Resistência à Insulina , Modelos Logísticos , Obesidade/fisiopatologia , Puberdade , Fatores de Risco
16.
Tumori ; 68(6): 537-42, 1982 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-6897752

RESUMO

Cutaneous and visceral dissemination of Kaposi's sarcoma (KS) occurred in a patient with angioimmunoblastic lymphadenopathy with dysproteinemia (AILD) who had been treated with combination chemotherapy. Three other cases of KS complicating immunosuppressive therapy of AILD have been reported in the literature, and there is evidence to indicate that AILD displays features which are known to predispose to KS. Like in other subjects with profound immunodeficiency (e.g. in young homosexual men), in our patient KS pursued an unusually aggressive course, with involvement of lymph nodes and internal organs as well as the skin. It is concluded that the risk of developing severe KS is a further reason to avoid aggressive combination chemotherapy in patients with AILD, particularly in those of Jewish or Mediterranean ancestry. Even the use of corticosteroids should be reduced to a minimum to avoid immunosuppression, and a conservative approach to treatment seems advisable.


Assuntos
Antineoplásicos/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica , Linfadenopatia Imunoblástica/complicações , Sarcoma de Kaposi/induzido quimicamente , Idoso , Quimioterapia Combinada , Feminino , Humanos , Linfadenopatia Imunoblástica/tratamento farmacológico , Linfadenopatia Imunoblástica/patologia , Linfonodos/patologia , Mecloretamina/efeitos adversos , Prednisona/efeitos adversos , Procarbazina/efeitos adversos , Sarcoma de Kaposi/patologia , Pele/patologia , Vincristina/efeitos adversos
17.
Tumori ; 71(6): 547-54, 1985 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-4082287

RESUMO

Serum ferritin has been suggested as a tumor marker in the diagnosis of certain malignancies and for following the activity or dissemination of the malignant process. Since neoplastic tissues generally contain more acidic isoferritins than their normal tissue counterparts, it has also been suggested that the specific assay of such isoferritins in serum may be of particular value in the diagnosis of malignancy. In this work, we have evaluated ferritin concentration in the serum of normal subjects and patients with acute nonlymphocytic leukemia, Hodgkin's disease, breast cancer and lung cancer by simultaneously using three different immunoassays: an immunoradiometric assay based on polyclonal antibodies against human liver (basic, L-subunit rich) ferritin, a radioimmunoassay based on polyclonad antibodies against HeLa cell (acidic, H-subunit rich) ferritin, and an immunoradiometric assay based on the monoclonal antibody 2A4 raised against human heart (acidic, H-subunit rich) ferritin. Most of the patients studied had increased values for liver-type ferritin in the absence of increased iron stores. Binding of serum ferritin to concanavalin A did not prove to be useful in distinguishing a tumor-specific basic isoferritin. The HeLa ferritin assay was found to be less specific than the heart ferritin assay in the detection of acidic isoferritins, and did not provide any advantage over the liver assay in detecting the increased levels of serum ferritin associated with malignant disease. Heart-type ferritin was found in one-fifth of normal sera and 64% of sera from patients with malignancy. Values were very low compared with those for basic ferritin, ranging from less than 0.1 to 17% of total serum ferritin (geometric mean value 1.3%) in patients with malignancy. These findings indicate that at present there is little application for serum ferritin immunoassays based on antibodies to HeLa cell or heart ferritin in the diagnosis or monitoring of malignant disease. This seems to be due to the presence in human serum of biding factors which are responsible for the rapid clearance of acidic isoferritins from the circulation. The serum concentration of basic ferritin, however, can be useful in the diagnosis and management of some malignancies, and it is possible that studies on cell isoferritins can be important in biologic monitoring of neoplastic disorders. It should also be noted that the increased levels of serum ferritin found in patients with malignancy can exert adverse effects on the host immune response and perhaps an inhibitory effect on hematopoiesis.


Assuntos
Ferritinas/sangue , Imunoensaio/métodos , Neoplasias/sangue , Anticorpos Monoclonais , Concanavalina A/metabolismo , Ferritinas/imunologia , Células HeLa , Humanos , Fígado/metabolismo , Miocárdio/metabolismo
18.
Minerva Med ; 80(5): 451-4, 1989 May.
Artigo em Italiano | MEDLINE | ID: mdl-2501714

RESUMO

The behaviour of sideremia has been studied in order to assess the intestinal absorption of iron of a new compound, ferric chondroitin sulfate after oral administration in 12 normal volunteers. After administration of 90 mg of iron as ferric chondroitin sulfate, sideremia rose from a basal value of 88 +/- 27 micrograms/dl to a value of 128 +/- 22 micrograms/dl at the third hour. Variance analysis showed that the increases were statistically significant (F = 27.7; p less than 0.00001). In the same subjects, the test was carried out in accordance with a randomised crossover design in two periods after administration of 91 mg of ferritin iron: sideremia rose from a basal value of 92 +/- 27 micrograms/dl to a value at the third hour of 97 +/- 28 micrograms/dl, moderate increases but statistically significant (F = 3.2; P = 0.0354). Variance analysis by repeated measurements showed that increases in sideremia were significantly higher after iron administration as ferric chondroitin sulfate than after administration of ferritin iron (F = 13.18; p = 0.0042). This study documents the good bioavailability of the iron contained in ferric chondroitin sulfate.


Assuntos
Sulfatos de Condroitina/administração & dosagem , Condroitina/análogos & derivados , Compostos Férricos/sangue , Absorção Intestinal , Administração Oral , Adulto , Análise de Variância , Disponibilidade Biológica , Sulfatos de Condroitina/farmacocinética , Feminino , Ferritinas/administração & dosagem , Ferritinas/farmacocinética , Humanos , Masculino , Valores de Referência , Fatores de Tempo
19.
Chir Ital ; 47(1): 24-43, 1995.
Artigo em Italiano | MEDLINE | ID: mdl-8706183

RESUMO

The authors describe the technique for the treatment of gallbladder stones using a laparoscopic approach and discuss the diagnostic and operative flow chart stressing complications and ways to avoid them. A total of 2517 non-selected patients underwent surgery since october 1990 up to september 1995. 252 were affected by acute cholecystitis (10%); 172 underwent emergency laparoscopic cholecystectomy. ERCP was performed in 278 patients (11.04%): 177 underwent endoscopic sphincterotomy and laparoscopic cholecystectomy, 21 underwent laparoscopic cholecystectomy before sphincterotomy, 8 laparoscopic cholecystectomy and ESWL. Laparoscopic cholecystectomy was converted into laparotomy in 37 patients (1.4%); surgery was abandoned in 3 patients following to onset of intense bradycardia. Major complications were observed in 0.63%; bile duct injury occurred in four patients (0.15%). One patient died following a massive intraoperative myocardial infarction. Average operative time was 21 minutes. Only 22.8% of patients required mild analgesia on the first day after surgery. The average hospital postoperative stay was 2.6 days. Return to work took place in 98% of non complicated patients within one week of being discharged from hospital.


Assuntos
Colecistectomia Laparoscópica , Colelitíase/cirurgia , Colecistectomia Laparoscópica/efeitos adversos , Colecistectomia Laparoscópica/instrumentação , Colecistectomia Laparoscópica/métodos , Colecistectomia Laparoscópica/normas , Feminino , Humanos , Gravidez , Complicações na Gravidez/cirurgia
20.
J Chir (Paris) ; 130(5): 226-30, 1993 May.
Artigo em Francês | MEDLINE | ID: mdl-8345019

RESUMO

Eleven patients underwent choledochoduodenostomy under laparoscopic control: 5 for adenocarcinoma of head of pancreas, including 2 with extension into duodenum, 3 for chronic pancreatitis. 1 for gastric carcinoma with pancreatic infiltration 1 for carcinoma of ampulla and 1 for stenosing papillitis. Mean duration of operation was 97.9 minutes and mean hospital stay 7.8 days. No immediate or delayed postoperative complications were reported. The advantages of this method are the marked reduction in recovery time, especially in severely debilitated elderly patients, and the absence of postoperative pain.


Assuntos
Ducto Colédoco/cirurgia , Duodeno/cirurgia , Laparoscopia , Adenocarcinoma/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Anastomose Cirúrgica/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/secundário , Neoplasias Pancreáticas/cirurgia , Pancreatite/cirurgia , Neoplasias Gástricas/patologia , Neoplasias Gástricas/cirurgia
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