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1.
Drugs Today (Barc) ; 47(4): 277-88, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21573251

RESUMO

Ongoing progress in understanding the pathogenic mechanisms regulating various immune-mediated and inflammatory diseases, as well as the availability of innovative biotechnological approaches, have lead to the development of new drugs that add to conventional treatments. Among these, tumor necrosis factor (TNF)-α inhibitors such as infliximab, adalimumab, etanercept, golimumab and certolizumab pegol, are now available for clinical use. Adalimumab is a fully recombinant human immunoglobulin G1 monoclonal antibody that specifically binds with high affinity to human TNF-α and inhibits its binding to TNF receptors. Adalimumab was approved by the U.S. FDA in 2002 and was granted approval from the European Medicines Agency in September 2003 for the treatment of moderate to severe rheumatoid arthritis and subsequently for the treatment of ankylosing spondylitis, chronic plaque psoriasis, psoriatic arthritis, juvenile idiopathic arthritis and Crohn's disease. In this paper, we will briefly review the structure and biological effects of TNF-α, the old and recent indications of adalimumab, the pretreatment considerations, the reported adverse events and finally, the recommendations for its use in pregnancy.


Assuntos
Anti-Inflamatórios/uso terapêutico , Anticorpos Monoclonais/uso terapêutico , Antirreumáticos/uso terapêutico , Doenças Autoimunes/tratamento farmacológico , Doenças do Sistema Imunitário/tratamento farmacológico , Adalimumab , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais Humanizados , Infecções Bacterianas/prevenção & controle , Feminino , Humanos , Inflamação/tratamento farmacológico , Gravidez , Tuberculose/prevenção & controle , Fator de Necrose Tumoral alfa/antagonistas & inibidores
2.
Cancer Gene Ther ; 17(9): 645-54, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20467452

RESUMO

The observation that depletion or inhibition of regulatory T cells (Tregs) unleashes efficient antitumor effector immune responses that can lead to tumor eradication in mice has opened new perspectives for the development of cancer immunotherapy. The quality and overall efficiency of the effector immune responses induced in the absence of Tregs seem to depend on multiple factors that determine the result of a battle involving effector T cells (Teffs), Tregs and tumor cells. In this study, we investigated the quality of tumor-associated antigens (TAAs) as one such factor. We show that the presence of a strong dominant antigen is required for the induction of effector responses capable of tumor eradication in the absence of Tregs. The sole addition of a dominant antigen on tumor cells does not change tumor growth in unmanipulated mice, but improves tumor eradication rate from a few to almost 100% in the absence of Tregs. This eradication can be shown to result from the recruitment and activation of specific Teffs recognizing this antigen. We also show that the presence of such dominant antigens has the side effect of restricting the breadth of the immune response to other TAAs, which could favor the generation of escape mutant by tumor editing. Taken together, our results highlight the potential, and some requirements for cancer immunotherapy based on Treg depletion. They also show that, ultimately, tumor fate depends on multiple factors that should all be taken into consideration for the design of more efficient immunotherapy.


Assuntos
Antígenos de Neoplasias/imunologia , Imunoterapia , Neoplasias Mamárias Animais/imunologia , Mesotelioma/imunologia , Linfócitos T Reguladores/imunologia , Animais , Western Blotting , Feminino , Citometria de Fluxo , Glicoproteínas de Hemaglutininação de Vírus da Influenza/metabolismo , Linfonodos/imunologia , Linfonodos/patologia , Neoplasias Mamárias Animais/patologia , Neoplasias Mamárias Animais/terapia , Mesotelioma/patologia , Mesotelioma/terapia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas
3.
Int J Immunopathol Pharmacol ; 22(3): 557-65, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19822072

RESUMO

The ongoing progresses in the knowledge of the pathogenic mechanisms of various inflammatory or immune-mediated diseases and the availability of innovative biotechnological approaches have lead to the development of new drugs which add to conventional treatments. TNF-alpha inhibitors (infliximab, adalimumab and etanercept) have demonstrated efficacy either as monotherapy or in combination with other anti-inflammatory or disease modifying anti-rheumatic drugs (DMARDs). The efficacy and safety profile of the TNF-alpha inhibitors can be considered, in general, as a class effect. Nevertheless, some differences may exist among the three agents. In this paper, we will briefly review the indications for the use of the three TNF-alpha inhibitors, the pre-treatment considerations and the reported adverse events.


Assuntos
Anti-Inflamatórios/uso terapêutico , Inflamação/tratamento farmacológico , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Adalimumab , Animais , Anti-Inflamatórios/efeitos adversos , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Humanizados , Quimioterapia Combinada , Etanercepte , Humanos , Imunoglobulina G/uso terapêutico , Inflamação/imunologia , Infliximab , Infecções Oportunistas/etiologia , Seleção de Pacientes , Receptores do Fator de Necrose Tumoral/uso terapêutico , Medição de Risco , Fatores de Risco , Resultado do Tratamento , Tuberculose/etiologia
4.
Allergy ; 63(10): 1335-8, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18782112

RESUMO

BACKGROUND: Allergic rhinitis (AR) is characterized by Th2-polarized immune response. Soluble HLA (sHLA) molecules play an immunomodulatory activity. So far, however, no study investigated them in AR. OBJECTIVE: The aim of this study was to evaluate sHLA-G and sHLA-A,-B,-C serum levels in AR patients with pollen allergy and in a group of healthy controls. METHODS: Forty-nine AR patients were enrolled. A group of healthy nonallergic subjects was considered as control. sHLA-G and sHLA-A,-B,-C serum levels were determined by immunoenzymatic method. The study was conducted during the winter, such as outside the pollen season. RESULTS: Allergic patients had significantly higher levels of both sHLA-G (P < 0.0001) and sHLA-A,-B,-C (P = 0.011) molecules than normal controls. Moreover, there was a significant relationship between these two soluble molecules (r = 0.69) in allergic patients. CONCLUSION: The present study provides the first evidence that both sHLA-G and sHLA-A,-B,-C serum levels are significantly increased in AR patients with pollen allergy.


Assuntos
Antígenos HLA/sangue , Antígenos de Histocompatibilidade Classe I/sangue , Rinite Alérgica Perene/imunologia , Rinite Alérgica Sazonal/imunologia , Adulto , Feminino , Antígenos HLA/biossíntese , Antígenos HLA-A/biossíntese , Antígenos HLA-A/sangue , Antígenos HLA-B/biossíntese , Antígenos HLA-B/sangue , Antígenos HLA-C/biossíntese , Antígenos HLA-C/sangue , Antígenos HLA-G , Antígenos de Histocompatibilidade Classe I/biossíntese , Humanos , Masculino , Pessoa de Meia-Idade , Pólen/imunologia , Rinite Alérgica Perene/sangue , Rinite Alérgica Sazonal/sangue , Solubilidade , Regulação para Cima/imunologia
5.
J Biol Regul Homeost Agents ; 22(2): 117-23, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18597704

RESUMO

Allergic rhinitis (AR) is characterized by a Th2 polarized immune response. Specific Immunotherapy modifies this bias restoring a physiologic Th1 profile. Sublingual immunotherapy (SLIT) is widely prescribed, but there is no early, simple marker of response. This study was undertaken in order to determine whether serum IL-4 might be a possible marker of SLIT immunological response in order to quickly and easily detect responder patients. Thirty-nine AR patients with a pollen allergy assumed preseasonal SLIT for 3 months. VAS for symptoms and medication efficacy were evaluated. Serum IL-4 was assessed before and 3 and 6 months after SLIT initiation. Eighty-two percent of patients (32/39) showed a clinical response to SLIT. Serum IL-4 significantly decreased at 6 months post-therapy in responders, whereas it increased in non-responders. In conclusion, these results may be considered clinically relevant proof that SLIT treatment induces a quick reduction in Th2 polarization. Serum IL-4 appears to be an early marker of immunological response to SLIT.


Assuntos
Imunoterapia , Interleucina-4/sangue , Rinite Alérgica Sazonal/imunologia , Rinite Alérgica Sazonal/terapia , Administração Sublingual , Adolescente , Adulto , Idoso , Biomarcadores/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Regressão , Fatores de Tempo
7.
Hum Reprod ; 20(12): 3514-7, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16155083

RESUMO

INTRODUCTION: This study aimed to investigate asthma prevalence and severity in women with and without endometriosis. METHODS: Before laparoscopy, asthma prevalence was evaluated in 879 women of reproductive age, undergoing surgery because of benign gynaecological conditions. Diagnosis of bronchial asthma was based on the American Thoracic Society criteria; asthma severity was classified in four categories according to the 2002 Global Initiative for Asthma guidelines. Asthmatic patients completed the Living with Asthma Questionnaire (LWAQ). Endometriosis was confirmed histologically and classified according to the revised American Fertility Society criteria. RESULTS: There were no significant differences in age, smoking status, and other demographic and health characteristics between patients with endometriosis (n = 467) and controls (n = 412). Asthma prevalence was similar in women with (23/467, 4.9%; 95% CI, 3.1-7.3) and without (22/412, 5.3%; 95% CI, 3.4-8.0; P = 0.781) endometriosis. Asthma severity was similar in women with and without endometriosis, with 12 (52.2%) women with endometriosis and 13 (59.1%) controls being in the intermittent (mildest) degree of severity. No significant difference was observed between women with and without endometriosis in the LWAQ total score. CONCLUSIONS: Women with endometriosis do not have an increased risk of having asthma.


Assuntos
Asma/complicações , Endometriose/complicações , Adulto , Asma/patologia , Estudos de Casos e Controles , Endometriose/patologia , Feminino , Humanos , Laparoscopia , Modelos Estatísticos , Prevalência , Qualidade de Vida , Risco , Índice de Gravidade de Doença
8.
Minerva Ginecol ; 55(2): 139-51, 151-8, 2003 Apr.
Artigo em Inglês, Italiano | MEDLINE | ID: mdl-12712000

RESUMO

The objective of this article is to review the aetiology, epidemiology, diagnosis, clinical course, treatment and prognosis of peripartum cardiomyopathy (PPCM). The medical literature from 1966 to March 2002 was reviewed through MEDLINE. PPCM is a rare complication in pregnancy. It is seen in late pregnancy or in the early puerperium. The aetiology of this disease remains uncertain. Many possible causes have been proposed, including myocarditis, abnormal immune response to pregnancy, maladaptive response to the hemodynamic stresses of pregnancy and prolonged tocolysis. Risk factors for PPCM include advanced maternal age, multiparity, African descent, twinning and long-term tocolysis. Patients with systolic dysfunction during pregnancy are treated the same as patients who are not pregnant. The mainstays of medical therapy are digoxin, loop diuretics, sodium restriction and afterload reducing agents (hydralazine and nitrates). Due to a high risk for venous and arterial thrombosis, anticoagulation with heparin should be instituted. Angiotensin-converting enzyme inhibitors and angiotensin receptor blockers should be avoided during pregnancy because of severe adverse neonatal effects. The utility of immunosuppressive therapy remains ambiguous. Advances in medical therapy for dilated cardiomyopathy and cardiac transplantation have significantly improved the quality of life and survival for patients.


Assuntos
Cardiomiopatias/fisiopatologia , Período Pós-Parto/fisiologia , Cardiomiopatias/diagnóstico , Cardiomiopatias/tratamento farmacológico , Eletrocardiografia , Feminino , Humanos , Gravidez , Complicações na Gravidez , Fatores de Tempo
9.
Br J Cancer ; 86(3): 477-84, 2002 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-11875718

RESUMO

Mxi1 is a Mad family member that plays a role in cell proliferation and differentiation. To test the role of Mxi1 on tumorigenesis of glioma cells we transfected a CMV-driven MXI1 cDNA in U87 human glioblastoma cells. Two clones were isolated expressing MXI1 levels 18- and 3.5-fold higher than wild-type U87 cells (clone U87.Mxi1.14 and U87.Mxi1.22, respectively). In vivo, U87.Mxi1.14 cells were not tumorigenic in nude mice and delayed development of tumours was observed with U87.Mxi1.22 cells. In vitro, the proliferation rate was partially and strongly inhibited in U87.Mxi1.22 and U87.Mxi1.14 cells respectively. The cell cycle analysis revealed a relevant accumulation of U87.Mxi1.14 cells in the G(2)/M phase. Interestingly, the expression of cyclin B1 was inhibited to about 60% in U87.Mxi1.14 cells. This inhibition occurs at the transcriptional level and depends, at least in part, on the E-box present on the cyclin B1 promoter. Consistent with this, the endogenous Mxi1 binds this E-box in vitro. Thus, our findings indicate that Mxi1 can act as a tumour suppressor in human glioblastomas through a molecular mechanism involving the transcriptional down-regulation of cyclin B1 gene expression.


Assuntos
Diferenciação Celular/fisiologia , Divisão Celular/efeitos dos fármacos , Divisão Celular/fisiologia , Ciclina B/genética , Proteínas de Ligação a DNA/metabolismo , Regulação Neoplásica da Expressão Gênica , Fatores de Transcrição/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos , Ciclo Celular/fisiologia , Ciclina B1 , Proteínas de Ligação a DNA/genética , Fase G2 , Genes Reporter , Glioma , Humanos , Cinética , Mitose , Proteínas Recombinantes/farmacologia , Fatores de Tempo , Fatores de Transcrição/genética , Transcrição Gênica , Transfecção , Células Tumorais Cultivadas , Proteínas Supressoras de Tumor
10.
Cancer Res ; 61(6): 2386-9, 2001 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-11289101

RESUMO

Dendritic cells (DCs) are professional antigen-presenting cells (APCs) that need to be activated before they can function to initiate primary and secondary immune responses in vivo. DCs are also specialized to maintain peripheral tolerance to self after uptake of apoptotic material, likely corresponding to both apoptotic bodies and whole apoptotic cells. Here, we report that murine bone marrow-derived DCs can be activated in vitro by exogenous signals received from apoptotic leukemia cells expressing on the cell surface a model tumor-associated antigen. Injected in vivo, these exogenously activated DCs can function as adjuvants to protect mice against leukemia by stimulating an antigen-specific cellular-mediated cytotoxic immune response. To our knowledge, this is the first report indicating that DCs loaded with apoptotic leukemia cells protect mice against leukemia development.


Assuntos
Apoptose/fisiologia , Vacinas Anticâncer/imunologia , Células Dendríticas/imunologia , Leucemia L1210/imunologia , Animais , Antígenos de Neoplasias/imunologia , Células da Medula Óssea/citologia , Células da Medula Óssea/imunologia , Antígenos CD4/genética , Antígenos CD4/imunologia , Citotoxicidade Imunológica , Feminino , Técnicas de Transferência de Genes , Humanos , Imunoterapia Adotiva , Leucemia L1210/genética , Leucemia L1210/prevenção & controle , Camundongos , Camundongos Endogâmicos DBA , Fagocitose/imunologia
11.
Immunology ; 99(1): 8-15, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10651935

RESUMO

Dendritic cells (DC) are extremely efficient at generating both prophylactic and therapeutic anti-tumour immunity. We aimed to analyse the respective roles of humoral and cellular immune responses generated in mice vaccinated with bone marrow (BM)-derived DC in terms of in vivo anti-leukaemia effect. We used the murine L1210 B lymphocytic leukaemia genetically modified to express on the cell surface of human CD4 (hCD4) (L1210/hCD4) as a model tumour-associated antigen (TAA). DC cultures were loaded with either purified soluble hCD4 (shCD4) protein or unfractionated L1210/hCD4 extracts and injected as vaccine into mice. The efficacy of these vaccinations was compared with that of vaccination with shCD4 protein emulsified in Freund's adjuvant (FA). We evaluated the immune responses generated after these vaccinal protocols and the survival rate of vaccinated mice subsequently challenged with a lethal injection of L1210/hCD4 cells. Our results demonstrated that vaccination with shCD4 protein or tumour extract-loaded DC mainly generated an hCD4 antigen-specific cell-mediated cytotoxic immune response that was associated with a specific protection against leukaemia. In contrast, vaccination with the protein emulsified in FA only generated potent humoral immune responses that were not protective against leukaemia. Altogether, our results indicate that the unique property of loaded DC to trigger an anti-leukaemia protective effect is mainly associated with cellular immune responses.


Assuntos
Antígenos CD4/imunologia , Vacinas Anticâncer/administração & dosagem , Células Dendríticas/imunologia , Imunoterapia Adotiva/métodos , Leucemia Experimental/prevenção & controle , Linfócitos T Citotóxicos/imunologia , Animais , Antígenos CD4/administração & dosagem , Vacinas Anticâncer/imunologia , Ensaio de Imunoadsorção Enzimática , Feminino , Citometria de Fluxo , Antígenos de Histocompatibilidade Classe I/imunologia , Leucemia Experimental/imunologia , Camundongos , Camundongos Endogâmicos DBA , Organismos Livres de Patógenos Específicos , Células Tumorais Cultivadas
12.
Immunology ; 96(4): 569-77, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10233743

RESUMO

Dendritic cells (DC) are professional antigen-presenting cells that can be used as immune adjuvant for anti-tumoural therapies. This approach requires the generation of large quantities of DC that are fully characterized on the immunophenotypical and functional levels. In a murine model, we analysed the in vitro effects of granulocyte-macrophage colony-stimulating factor (GM-CSF) alone or combined with interleukin-4 (IL-4) or Flt3 ligand (Flt3-L) on the number, immunophenotype and functions of bone marrow-derived DC. In GM-CSF cultures, we have identified two populations based on their level of expression of major histocompatibility complex (MHC) class II molecules: MHC-IIhi cells, exhibiting the typical morphology and immunophenotype of myeloid DC (CD11c+ 33D1+ DEC-205+ F4/80+), and MHC-IIlo cells, heterogeneous for DC markers (30% CD11c+; 50% 33D1+; DEC-205-; F4/80+). The addition of Flt3-L to GM-CSF induced a twofold increase in MHC-IIhi DC number; besides, the MHC-IIlo cells lost all DC markers. In contrast, after addition of IL-4 to GM-CSF, the two populations displayed a very similar phenotype (CD11c+ 33D1- DEC-205+ F4/80-), differing only in their expression levels of MHC class II and costimulatory molecules, and showed similar stimulatory activity in mixed leucocyte reaction. We next analysed the migration of these cultured cells after fluorescent labelling. Twenty-four hours after injection into the footpads of mice, fluorescent cells were detected in the draining popliteal lymph nodes, with an enhanced migration when cells were cultured with GM-CSF+Flt3-L. Finally, we showed that MHC-IIhi were more efficient than MHC-IIlo cells in an anti-tumoral vaccination protocol. Altogether, our data highlight the importance of characterizing in vitro-generated DC before use in immunotherapy.


Assuntos
Células da Medula Óssea/imunologia , Vacinas Anticâncer/uso terapêutico , Citocinas/imunologia , Células Dendríticas/imunologia , Animais , Diferenciação Celular/imunologia , Feminino , Fator Estimulador de Colônias de Granulócitos e Macrófagos/imunologia , Antígenos de Histocompatibilidade Classe II/metabolismo , Imunofenotipagem , Interleucina-4/imunologia , Leucemia L1210/prevenção & controle , Linfonodos/imunologia , Teste de Cultura Mista de Linfócitos , Masculino , Proteínas de Membrana/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Células Tumorais Cultivadas , Vacinação
13.
Gene Ther ; 5(9): 1221-6, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9930323

RESUMO

In tumors, gap junctional intercellular communication (GJIC) is usually down-regulated and the expression of connexins, membrane proteins constituting gap junction channels, is often low or altered. GJIC, allowing the intercellular diffusion of ganciclovir (GCV) triphosphate, is also one mediator of the 'bystander effect', the phenomenon by which herpes simplex virus thymidine kinase (HSVtk)-transduced, neoplastic cells kill surrounding HSVtk-negative cells when treated with GCV. We set up experiments to evaluate the effects of retrovirus-mediated in vivo gene transfer of connexin 43 in malignancies with low GJIC capacity. We found that U-87 human glioblastoma cells transfected in vitro by the human Cx43 cDNA grow significantly more slowly than control U-87 cells and lose their tumorigenicity when injected subcutaneously in nude mice. When the Cx43 gene was transduced in vitro in U-87 cells by a retroviral producer cell line (N3.2.ii, titer 1.5 x 10(6) c.f.u./ml) in vivo results were similar. However, only when U-87 cells were co-injected with N3.2.ii cells in nude mice in a 1:5 ratio, a 50% reduction in tumor size was obtained during the first 3 weeks. Moreover the coinjection of U-87 cells with N3.2.ii and SBA cells (a retroviral producer cell line expressing the HSVtk gene), was not able to potentiate the effects of GCV administration, suggesting that Cx43 gene transfer requires more efficient vectors to increase the bystander effect in vivo.


Assuntos
Conexina 43/genética , Técnicas de Transferência de Genes , Terapia Genética/métodos , Glioma/terapia , Retroviridae/genética , Animais , Antivirais/uso terapêutico , Feminino , Ganciclovir/uso terapêutico , Vetores Genéticos , Glioma/tratamento farmacológico , Camundongos , Camundongos Nus , Timidina Quinase/genética , Células Tumorais Cultivadas
14.
Hum Gene Ther ; 8(11): 1345-53, 1997 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-9295129

RESUMO

The growth of U-87 or C6 gliomas co-implanted in nude mice with retroviral producer cells (VPC) expressing the herpes simplex virus-thymidine kinase (HSV-tk) gene is only partially impaired by treatment with ganciclovir (GCV). The effect of GCV is even less evident when C6 and VPC are co-implanted into the rat brain. Furthermore, tumors from C6 cells carrying the HSV-tk gene are not eradicated by GCV, although they remain sensitive to GCV when replated in vitro. These limits of the HSV-tk/GCV system in glioma gene therapy may be due to insufficient gene transfer and/or insufficient delivery of GCV to glioma cells. Combination of HSV-tk and one or more cytokines may improve the antitumor efficacy. Among cytokines, interleukin-4 (IL-4) has already been shown to be active against gliomas. In nude mice, GCV treatment inhibited tumor growth more effectively after co-injection of C6 cells with a mixture of VPC transducing IL-4 and HSV-tk genes than after co-injection with either IL-4 or HSV-tk VPC only. In immunocompetent Sprague-Dawley rats, co-injection of IL-4 VPC and C6 cells was also effective in inhibiting the growth of C6 brain tumors, 38% of the animals surviving for at least 2 months. Furthermore, increased and prolonged antitumor efficacy was obtained by transducing both IL-4 and HSV-tk genes.


Assuntos
Antimetabólitos/farmacologia , Ganciclovir/farmacologia , Terapia Genética , Glioma/terapia , Interleucina-4/genética , Simplexvirus/enzimologia , Timidina Quinase/genética , Proteínas Virais/genética , Animais , Feminino , Técnicas de Transferência de Genes , Vetores Genéticos , Interleucina-4/metabolismo , Interleucina-4/uso terapêutico , Camundongos , Camundongos Nus , Ratos , Ratos Sprague-Dawley , Retroviridae/genética , Transdução Genética
15.
Am J Hum Genet ; 58(6): 1260-7, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8651304

RESUMO

The loss of genetic material on chromosome 10q is frequent in different tumors and particularly in malignant gliomas. We analyzed 90 of these tumors and found loss of heterozygosity (LOH) in >90% of the informative loci in glioblastoma multiforme (GBM). Initial studies restricted the common LOH region to 10q24-qter. Subsequently, the study of a pediatric GBM suggested D10S221 and D10S209, respectively, as centromeric and telomeric markers of a 4-cM LOH region. It is interesting to note that, in one subset of cells from this tumor, locus D10S209 seems involved in the allelic imbalance of a larger region, with D10S214 as telomeric marker. This 17-cM region contains the D10S587-D10S216 interval of common deletion recently defined on another set of gliomas.


Assuntos
Neoplasias Encefálicas/genética , Cromossomos Humanos Par 10 , Deleção de Genes , Genes Supressores de Tumor , Glioma/genética , Neoplasias Encefálicas/patologia , Centrômero , Criança , Mapeamento Cromossômico , DNA de Neoplasias/análise , Marcadores Genéticos , Biblioteca Genômica , Glioma/patologia , Humanos , Hibridização in Situ Fluorescente , Cariotipagem , Imageamento por Ressonância Magnética , Telômero
16.
Hum Gene Ther ; 6(6): 763-72, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7548276

RESUMO

Cells expressing the herpes simplex-thymidine kinase (HS-TK) gene as a consequence of retroviral transduction, as well as TK-negative (TK-) bystander cells, can be killed by treatment with ganciclovir (GCV). In vitro, this "bystander effect," has been attributed to metabolic cooperation through gap junctions or to the uptake of apoptotic vesicles. We show that GCV treatment kills TK-negative U-87 glioma cells cocultured with cells that express TK (TK+) but that have lost the capacity for releasing retroviral particles. A photometric enzyme immunoassay identifies histone-associated DNA fragments, typical of apoptosis, in the cytosol of GCV-treated TK+ cells, and apoptotic features are also demonstrated by ultrastructural studies. Northern blot analysis and the reverse transcription polymerase chain reaction (PCR) show that connexin 43, a major constituent of gap junctions, is expressed in TK+ and U-87 cells. The size of U-87 tumors in nude mice subsequently injected with TK+ cells and GCV is not significantly different than in untreated animals; whereas, after injecting 1:1 mixtures of U-87 and TK+ cells, GCV treatment only causes a temporary regression of tumor growth. On the contrary, when the injected mixtures contain PA317.STK.SBA (a retroviral producer cell line that can transduce efficiently the HS-TK gene) and U-87 cells, tumors are destroyed effectively by GCV treatment. Thus, an experimental setting in which U-87 gliomas are matched with cells that are able to express, but not to transduce, the HS-TK gene indicates that the bystander effect kills U-87 cells in vitro by mechanisms associated with apoptotic death. In vivo, this effect is not sufficient to restrain the tumor growth taking place in immunodeficient animals.


Assuntos
Comunicação Celular , Morte Celular/efeitos dos fármacos , Ganciclovir/farmacologia , Animais , Sequência de Bases , Comunicação Celular/genética , Conexina 43/genética , Primers do DNA , Técnicas de Transferência de Genes , Humanos , Camundongos , Camundongos Nus , Microscopia Eletrônica , Dados de Sequência Molecular , Ratos , Ratos Endogâmicos F344 , Simplexvirus/enzimologia , Simplexvirus/genética , Timidina Quinase/genética , Células Tumorais Cultivadas
17.
Cancer Genet Cytogenet ; 75(2): 77-89, 1994 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-8055485

RESUMO

We studied the karyotypes of eight differentiated gliomas, 19 anaplastic gliomas, and 23 glioblastomas (GBM). Normal stemlines were present in 70% of the differentiated and anaplastic gliomas; abnormalities were mostly characterized by loss of sex chromosomes. In GBM, on the contrary, only 13% of the stemlines were normal and three groups, 45,XO, near-diploid, and near tetraploid, could be identified. The most frequent alterations among GBM were: total or partial loss of chromosome 10 in nine cases, structural abnormalities of chromosome 9 in seven cases, and loss of the Y chromosome in stemline clones of seven cases. Less frequent abnormalities included chromosomes 7, 1, 3, and 19. Our data support the cytogenetic model of gliomas as multi-stage tumors. GBM, in particular, can originate from the evolution of astrocytomas but can also develop de novo. In both cases loss of genetic material on chromosome 10 seems to play a crucial role.


Assuntos
Neoplasias Encefálicas/genética , Aberrações Cromossômicas , Glioma/genética , Adulto , Idoso , Deleção Cromossômica , Feminino , Humanos , Cariotipagem , Masculino , Pessoa de Meia-Idade , Cromossomo X , Cromossomo Y
18.
Cancer Genet Cytogenet ; 74(2): 139-43, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8019958

RESUMO

We have studied alterations of the p53 gene in 27 patients with malignant gliomas. Loss of heterozygosity (LOH) was investigated by microsatellite analysis in 23 patients (22 informative) and detected in nine. Exons 5 through 9 were amplified by polymerase chain reaction (PCR) in these nine patients: alterations were found in five cases (three missense mutations, one non-sense mutation, and one putative deletion), while in four the DNA sequence was normal. In the four patients where LOH could not be studied, the p53 sequence from tumor DNA was normal. These results indicate that microsatellite analysis is a convenient tool for LOH detection at the p53 locus and that mutations of the p53 gene are present in only part of the patients with LOH, implying the possibility that another tumor suppressor gene is located in the proximity of the p53 locus.


Assuntos
Neoplasias Encefálicas/genética , Deleção Cromossômica , Genes p53 , Glioma/genética , Adulto , Idoso , Sequência de Bases , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Mutação , Reação em Cadeia da Polimerase
20.
Biochem Biophys Res Commun ; 180(2): 967-71, 1991 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-1659407

RESUMO

After partial hepatectomy in rats, a approximately 4-fold decrease in pp63 mRNA level was detected at 24 h, but not at earlier time points. In mice, during liver cell proliferation induced by 1,4-bis[2-(3,5-dichloropyridyloxy)]benzene and phenobarbital, pp63 transcript levels had a decrease of 40-50%. However, pp63 mRNA was 5-6 fold higher in murine hepatocellular tumors than in normal adult mouse liver.


Assuntos
Glicoproteínas/genética , Neoplasias Hepáticas Experimentais/fisiopatologia , Regeneração Hepática , Fígado/fisiologia , Fenobarbital/farmacologia , Proteínas Tirosina Quinases/antagonistas & inibidores , Piridinas/farmacologia , RNA Mensageiro/genética , Animais , Divisão Celular/efeitos dos fármacos , Cruzamentos Genéticos , Feminino , Expressão Gênica , Fígado/citologia , Fígado/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , RNA Mensageiro/metabolismo , Ratos , Ratos Endogâmicos , Receptor de Insulina , alfa-2-Glicoproteína-HS
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