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1.
J Natl Cancer Inst ; 83(18): 1307-15, 1991 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-1653364

RESUMO

To study the effect of drug resistance on the response of stage IV astrocytomas to interferon, a human glioblastoma multiforme cell line, GBM-18, was transfected with an expression-vector plasmid containing a human multidrug resistance (MDR) gene (pHaMDR1/A), and clones surviving in colchicine were isolated. GBM-18 multidrug-resistant subclones displayed cross-resistance to other chemotherapeutic agents, including vincristine, doxorubicin, and dactinomycin. The multidrug-resistant phenotype was reversible when GBM-18 multidrug-resistant cells were cultured in colchicine and the calcium-channel blocker verapamil. The level of the MDR1 gene (also known as PGY1) message was increased in GBM-18 multidrug-resistant cells selected for increased resistance to colchicine, and this effect was not correlated with an amplification of the MDR1 gene. In both parental GBM-18 and GBM-18 multidrug-resistant cells, growth was suppressed to a greater degree when cultures were treated with the combination of fibroblast interferon (IFN-beta) and immune interferon (IFN-gamma). Parental cells and multidrug-resistant subclones varied in their de novo and/or interferon-modulated expression of HLA class I and class II antigens, a high-molecular-weight melanoma-associated antigen, and intercellular adhesion molecule 1 (ICAM-1). Of the antigens tested, ICAM-1 and HLA class I antigens were the most sensitive to enhanced expression induced by IFN-beta and IFN-gamma when used alone or in combination. The results of the present study indicate that multidrug-resistant human glioblastoma multiforme cells retain their increased sensitivity to the antiproliferative activity of the combination of IFN-beta plus IFN-gamma, and differences in antigenic phenotype are apparent in independent multidrug-resistant glioblastoma multiforme clones.


Assuntos
Glioblastoma/genética , Glioblastoma/imunologia , Interferon Tipo I/farmacologia , Interferon gama/farmacologia , Anticorpos Monoclonais , Antígenos de Neoplasias/genética , Northern Blotting , Southern Blotting , Divisão Celular/efeitos dos fármacos , Resistência a Medicamentos/genética , Humanos , Fenótipo , Proteínas Recombinantes , Células Tumorais Cultivadas
2.
Leuk Res ; 9(8): 1051-8, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-2931557

RESUMO

We investigated the neoplastic cells obtained from 37 cases of 'non-B, non-T' (SIg-E-) acute lymphoblastic leukemia (ALL) for their expression of 13 distinct monoclonal antibody defined B lymphocyte associated differentiation antigens. We correlated the expression of these B cell antigens with terminal deoxynucleotidyl transferase (TdT), HLA-DR antigen, common ALL antigen (cALLa), and cytoplasmic mu heavy chain (Cu) expression by these neoplastic cells. In this way, we were able to describe a hierarchy of B lymphocyte associated differentiation antigens as well as the marked phenotypic heterogeneity of 'non-B, non-T' ALL. TdT and HLA-DR are expressed throughout the stages of B cell differentiation represented by 'non-B, non-T' ALL. The earliest B cell antigen appears to be Leu 12 (B4) followed by BA-2 and then BL2. OKB2, BL1 and BA-1 are acquired next, followed by B1, BL3, cALLa and Cu. BL7 appears just prior to SIg. OKB1, OKB4, OKB7 and BL4 appear at or after the time of SIg expression and hence are not expressed by 'non-B, non-T' ALL cells. This developmental hierarchy is supported by the results of phorbol ester (TPA) induction studies. Thus, cases of 'non-B, non-T' ALL constitute a useful model for probing the hierarchal expression of B cell antigens and delineating the B cell developmental pathway(s).


Assuntos
Antígenos de Superfície/biossíntese , Linfócitos B/imunologia , Leucemia Linfoide/imunologia , Anticorpos Monoclonais/imunologia , Antígenos de Diferenciação de Linfócitos B , Antígenos de Neoplasias/análise , Diferenciação Celular/efeitos dos fármacos , DNA Nucleotidilexotransferase/metabolismo , Antígenos HLA-DR , Antígenos de Histocompatibilidade Classe II/análise , Humanos , Cadeias Pesadas de Imunoglobulinas/análise , Cadeias mu de Imunoglobulina/análise , Neprilisina , Fenótipo , Espectrometria de Fluorescência , Acetato de Tetradecanoilforbol/farmacologia
3.
Int J Oncol ; 1(2): 227-39, 1992 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21584536

RESUMO

Fludarabine phosphate (FLU), the 2-fluro derivative of Ara-A, 9-beta-D-arabino-furanosyl-2-fluoroadenine, has been shown to display both in vitro and in vivo antiproliferative activity toward a variety of murine tumors and human lymphoid malignancies. In the present study, we have determined the effect of FLU, alone and in combination with recombinant human fibroblast interferon (IFN-B), on in vitro growth, gene expression and the antigenic phenotype of human glioblastoma multiforme (GBM) cells displaying a multidrug sensitive and a multidrug resistant (MDR) phenotype. FLU exhibited a marked differential toxicity toward GBM-MDR cells versus the multidrug sensitive GBM parental cell line. Growth of GBM-MDR cells for seven days in 2.5 to 7.5 muM FLU resulted in a dose-dependent reduction or elimination of growth which persisted after removal of this agent. In contrast, recovery from FLU-induced growth suppression was observed in parental multidrug sensitive GBM cells. Acquisition of increased FLU sensitivity in GBM-MDR cells did not appear to result from selection for a subset of sensitive cells or an artifact associated with the DNA-transfection process. This conclusion is supported by the similar pattern of FLU resistance in GBM-18 clones isolated after transfection with a cloned hygromycin resistance gene and selection for resistance to hygromycin. The antiproliferative and toxic effect of FLU was increased in GBM-MDR cells by simultaneous growth in IFN-B and the toxic effect of FLU could be blocked in a dose-dependent manner by the simultaneous addition of deoxycytidine. In contrast, the toxicity of FLU toward GBM-MDR cells was not altered when cells were grown in the presence or absence of colchicine or by the administration of verapamil, which can reverse the MDR phenotype in GBM-MDR cells. The selective toxicity of FLU toward GBM-MDR versus GBM-18 cells was not associated with a consistent differential change in all of the GBM-18 MDR clones in the steady-state mRNA levels of a number of genes, including mdr-1, c-myc, c-fos, JunB, C-jun, proliferative cell nuclear antigen (PCNA), interferon stimulated gene-15 (ISG-15), fibronectin, tenascin, Class I HLA antigen, intercellular adhesion molecule I (ICAM-1), beta-actin or GAPDH. A common change observed in both parental GBM-18 cells and MDR GBM-18 clones exposed to FLU was an increase in the steady-state mRNA levels of deoxycytidine kinase (DCT). Analysis of the antigenic phenotype in GBM and GBM-MDR cells by fluorescence activated cell sorter (FACS) analysis using specific monoclonal antibodies (MoAbs) recognizing ICAM-1, Class I HLA antigen and a high molecular weight-melanoma associated antigen (HMW-MAA) indicated that FLU was generally more active as an immunomodulating agent in MDR versus non-MDR GBM cells. Although the mechanism underlying the differential effect of FLU toward GBM-MDR versus GBM cells is not presently known, the present findings indicate that the growth inhibitory and immunomodulatory effects of FLU are enhanced in cells expressing an MDR phenotype resulting from overexpression of a cell membrane localized 170,000 M(r) glycoprotein (P-glycoprotein).

4.
Anticancer Res ; 8(3): 297-302, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-2839097

RESUMO

In the present study we have evaluated the effect of recombinant human fibroblast, IFN-beta ser, and immune, IFN-gamma, interferon, alone and in combination, on the proliferation of fifteen early passage human glioblastoma cell cultures. Explant cultures were established from glioblastoma tumor tissue obtained at the time of surgery. After sufficient outgrowth, cultures were dispersed with trypsin/versene and maintained as independent cell lines. IFN-beta ser induced a greater than or equal to 50% reduction in the 7 day growth of 6 of the 15 cultures. The majority of cultures, 9 of 15, displayed less than or equal to 50% growth suppression in comparison with control cultures after 7 days exposure to 2000 Units/ml of IFN-beta ser. When treated with 2000 Units/ml of IFN-gamma, only 1 of the 15 glioblastoma cultures exhibited a greater than or equal to 50% reduction in growth. In contrast, when treated with the combination of IFN-beta ser plus IFN-gamma, 1000 Units/ml of each interferon preparation, 12 of 15 cultures were inhibited by greater than or equal to 50% after 7 days growth. The combination of interferons was effective in suppressing glioblastoma growth both in cultures displaying relative sensitivity and those exhibiting innate resistance to either or both types of interferon when employed alone. One glioblastoma culture, G-7, was studied through 45 passages and displayed the same sensitivity at different passages to growth inhibition when exposed to IFN-beta ser, IFN-gamma or both interferons. Based on previous clinical studies indicating that IFN-beta or IFN-gamma when administered alone to patients do not generally alter the clinical progression of malignant gliomas, the present results suggest that the combination of IFN-beta plus IFN-gamma may prove more effective than either agent alone in the clinical treatment of patients with glioblastoma multiforme.


Assuntos
Neoplasias Encefálicas/patologia , Glioblastoma/patologia , Interferon Tipo I/farmacologia , Interferon beta , Interferon gama/farmacologia , Proteínas Recombinantes/farmacologia , Divisão Celular/efeitos dos fármacos , Depressão Química , Resistência a Medicamentos , Ensaios de Seleção de Medicamentos Antitumorais , Sinergismo Farmacológico , Humanos , Interferon beta-1a , Interferon beta-1b , Células Tumorais Cultivadas/efeitos dos fármacos
5.
Funct Neurol ; 4(2): 177-81, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2737507

RESUMO

In this paper we apply spectral analysis methods to heart rate variability to assess the autonomic nervous system activity in normal subjects and in patients affected by different degrees of diabetic autonomic neuropathy. The current opinion, based on different clinical tests, is that parasympathetic impairment occurs earlier in autonomic dysfunctions. However, the use of power spectrum density analysis based on a single parameter (heart rate) suggests a simultaneous involvement of parasympathetic and sympathetic pathways leading to the conclusion that perhaps the natural history of diabetic autonomic neuropathy should be substantially rewritten.


Assuntos
Doenças do Sistema Nervoso Autônomo/etiologia , Sistema Cardiovascular/fisiopatologia , Neuropatias Diabéticas/fisiopatologia , Sistema Nervoso Simpático/fisiopatologia , Nervo Vago/fisiopatologia , Doenças do Sistema Nervoso Autônomo/fisiopatologia , Sistema Cardiovascular/inervação , Frequência Cardíaca , Humanos
15.
Cell Immunol ; 123(2): 456-61, 1989 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-2790970

RESUMO

The internalization of surface immunoglobulin (Ig) by B lymphocytes is the first step in the antigen-presenting function performed by these cells. Mature B cells coexpress on their surface IgM and IgD. At this time, there is controversy over whether these two isotypes serve different functions in the antigen-presenting process. The results presented here show that the intracellular pattern of distribution of IgM and IgD after internalization is strikingly different in the B cell lines studied. These findings support the hypothesis that the role of the two Ig classes in the antigen-presenting function may be different.


Assuntos
Linfócitos B/fisiologia , Endocitose , Imunoglobulina D/metabolismo , Imunoglobulina M/metabolismo , Receptores de Antígenos de Linfócitos B/metabolismo , Animais , Linhagem Celular , Reagentes de Ligações Cruzadas , Técnicas In Vitro , Proteínas de Membrana/metabolismo , Camundongos
16.
J Biol Chem ; 255(10): 4763-5, 1980 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-7372609

RESUMO

Long term human lymphoid cells from normal subjects were able to convert [35S]homocysteine to [35S]-cystine. The labeled cystine was found incorporated into proteins. Cells cultured from a patient with vitamin B6-unresponsive cystathioninuria, which contain no measurable cystathionase activity, were unable to perform this conversion. This is the first direct demonstration of transsulfuration by diploid cells in culture.


Assuntos
Cistationina gama-Liase/metabolismo , Cistina/biossíntese , Homocisteína/metabolismo , Liases/metabolismo , Linfócitos/metabolismo , Linhagem Celular , Cistationina gama-Liase/deficiência , Humanos , Cinética , Radioisótopos de Enxofre
17.
J Cell Physiol ; 106(3): 369-74, 1981 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7217219

RESUMO

Long-term lymphoid cell lines (LTL) cultured under normal conditions use methionine primarily for protein synthesis, although a significant proportion is converted to S-adenosylmethionine (SAM) and used for synthesis of the polyamines, spermidine, and spermine. When LTL are cultured under conditions of high cell density, there is an initial phase of rapid protein synthesis and accumulation of SAM as found under normal culture conditions, but this soon ceases. Polyamine synthesis is small under these conditions, despite the presence of relatively large amounts of SAM.


Assuntos
Linfócitos/metabolismo , Metionina/metabolismo , Proteínas Sanguíneas/biossíntese , Contagem de Células , Linhagem Celular , Sobrevivência Celular , Humanos , Cinética , S-Adenosilmetionina/biossíntese , Espermidina/biossíntese , Espermina/biossíntese
18.
J Clin Gastroenterol ; 27(1): 85-9, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9706780

RESUMO

Immunoproliferative small intestinal disease (IPSID) is a rare lympho-proliferative disorder of the upper small intestine. It is considered a special form of MALT lymphoma with propensity to malignant transformation. This disorder is rare in pediatric literature. We report a case of IPSID in a 16-year-old boy with low-grade malignant transformation, presenting as severe malnutrition and a possible association with Helicobacter pylori. The patient responded well to an extended treatment with tetracycline and eradication of H. pylori.


Assuntos
Doença Imunoproliferativa do Intestino Delgado/diagnóstico , Síndromes de Malabsorção/etiologia , Adolescente , Helicobacter pylori/isolamento & purificação , Humanos , Doença Imunoproliferativa do Intestino Delgado/complicações , Doença Imunoproliferativa do Intestino Delgado/microbiologia , Doença Imunoproliferativa do Intestino Delgado/patologia , Intestino Delgado/patologia , Masculino , Estômago/microbiologia
19.
Blood ; 77(5): 948-53, 1991 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-1671649

RESUMO

The distribution of intercellular adhesion molecule-1 (ICAM-1), a ligand for lymphocyte function antigen-1, on hematopoietic tissue was determined using the anti-ICAM-1 monoclonal antibody CL203.4 with flow cytometry and short-term semi-solid hematopoietic progenitor cultures. After timed incubation in media with fetal bovine serum, 29% of erythroid burst-forming units (BFU-E), 24% of erythroid colony-forming units (CFU-E), and 52% of granulocyte-macrophage colony-forming units (CFU-GM) bone marrow progenitors expressed ICAM-1. This finding, which is consistent with the detection of ICAM-1 on acute non-lymphoblastic leukemic blasts, is at variance with recent reports. ICAM-1 was also detected on bone marrow blasts, proerythroblasts, promyelocytes, and cells of monocyte/macrophage lineage, but was not detected on erythroblasts, normoblasts, neutrophilic myelocytes, metamyelocytes, bands, or on most lymphocytes. These results indicate that maturation of cells of the erythroid and myeloid lineage is associated with loss of ICAM-1. The distribution of ICAM-1 on bone marrow progenitors, early precursor cells, and accessory cells in conjunction with the function of this molecule in cell-cell interactions suggests that ICAM-1 may play a role in the cell-cell and cell-stromal interactions that regulate hematopoiesis.


Assuntos
Antígenos CD/metabolismo , Medula Óssea/metabolismo , Moléculas de Adesão Celular/metabolismo , Células-Tronco Hematopoéticas/metabolismo , Anticorpos Monoclonais , Células da Medula Óssea , Citometria de Fluxo , Humanos , Molécula 1 de Adesão Intercelular , Leucemia de Células B/metabolismo , Leucemia Mieloide/metabolismo , Leucemia de Células T/metabolismo , Trombocitemia Essencial/metabolismo
20.
Cell Mol Biol ; 38(5): 513-27, 1992 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1281753

RESUMO

The active component of the honeybee hive product propolis, caffeic acid phenethyl ester (CAPE), has been shown to display increased toxicity toward various oncogene-transformed cell lines in comparison with their untransformed counterparts (Su et al., 4: 231-242, 1991). This observation provides support for the concept that it is the transformed phenotype which is specifically sensitive to CAPE. In the present study, we have determined the effect of CAPE on the growth and antigenic phenotype of a human melanoma cell line, HO-1, and a human glioblastoma multiforme cell line, GBM-18. For comparison, we have also tested the effects of mezerein (MEZ), mycophenolic acid (MPA) and retinoic acid (RA), which can differentially modulate growth, differentiation and the antigenic phenotype in these human tumor cell lines. Growth of both cell lines was suppressed by CAPE in a dose-dependent fashion, with HO-1 cells being more sensitive than GBM-18 cells. The antiproliferative effect of CAPE was enhanced in both cell types if CAPE and MEZ were used in combination. Growth suppression was associated with morphological changes in H0-1 cells, suggesting induction of a more differentiated phenotype. CAPE also differentially modulated the expression of several antigens on the surface of the two tumor cell lines. These results suggest a potential role for CAPE as an antitumor agent, an antigenic modulating agent and possibly a differentiation inducing agent.


Assuntos
Ácidos Cafeicos/farmacologia , Diterpenos , Glioblastoma/tratamento farmacológico , Melanoma/tratamento farmacológico , Álcool Feniletílico/análogos & derivados , Antígenos de Neoplasias , Antineoplásicos Fitogênicos/administração & dosagem , Ácidos Cafeicos/administração & dosagem , Diferenciação Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Citotoxinas/administração & dosagem , Citotoxinas/farmacologia , Glioblastoma/imunologia , Glioblastoma/patologia , Humanos , Melanoma/imunologia , Melanoma/patologia , Ácido Micofenólico/farmacologia , Fenótipo , Álcool Feniletílico/administração & dosagem , Álcool Feniletílico/farmacologia , Terpenos/administração & dosagem , Tretinoína/farmacologia , Células Tumorais Cultivadas/efeitos dos fármacos , Células Tumorais Cultivadas/imunologia , Células Tumorais Cultivadas/patologia
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