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1.
J Hum Hypertens ; 38(3): 257-266, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38049636

RESUMO

Hypertension increases risk of stroke and other cardiovascular diseases, however, its prevalence and determinants in South Asian urban communities using country representative community-based datasets is lacking. This study evaluated prevalence of hypertension and it's determinants among urban residents of three South Asian countries. Urban population data from demographic and health surveys in Bangladesh, India, and Nepal were extracted. Hypertension prevalence was defined as systolic/diastolic blood pressure ≥ 140/ 90 mmHg. Age, education, wealth, physical activity, alcohol, BMI were considered as risk factors associated with the increased risk of hypertension. We performed binary logistic regression and calculated adjusted Odds Ratios (AOR) with 95% confidence interval (CI) to assess factors related to hypertension. Hypertension prevalence was 37.4% in India, 25.1% in Bangladesh and 18.4% in Nepal. Prevalence increased with age in all settings. Females had reduced odds of hypertension in Bangladesh (AOR 0.75; CI: 0.69, 0.81) and Nepal (AOR 0.62; CI: 0.54, 0.71), but higher risk in India (AOR 2.54; CI: 2.45, 2.63). Low education, caffeine consumption, obesity was associated with higher prevalence of hypertension in all three countries. Smokers had increased odds of hypertension in India (AOR 1.11; CI: 1.06, 1.15) and Nepal (AOR 1.23; 1.02, 1.47). Overall, hypertension prevalence is high in all three countries. Modifiable socioeconomic and lifestyle factors (education, wealth index, smoking status, caffeine consumption and BMI) associated with hypertension. Comprehensive hypertension pacific and sensitive interventions (including behavioral modification treatments and timely screening and access to health care) are urgently needed to prevent and control hypertension among urban populations in South Asia.


Assuntos
Cafeína , Hipertensão , Feminino , Humanos , Prevalência , Obesidade/epidemiologia , Fatores de Risco , Hipertensão/diagnóstico , Hipertensão/epidemiologia , Índia/epidemiologia , Inquéritos Epidemiológicos , Fatores Socioeconômicos
2.
Heliyon ; 7(3): e06547, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33851047

RESUMO

The objective of this study was to explore the risk factors that can determine the age of mother at first birth in Albania. The necessary information was extracted from a nationally representative sample survey, Albania Demographic and Health Survey, 2017-18 dataset. To identify the possible risk factors of the age of mother at first birth, we applied quantile regression model. The mean age of mother at first birth was found to be 22.38 years with standard deviation of 3.56 years. The minimum and maximum age was reported 15 and 45 years, respectively. From the result of quantile regression, respondent's current age, education level and partner's higher education level were found positive impact on age of the mother at first birth. However, rural area, partner's age and smoking status found negative impact on age of the mother at first birth. This study suggests that women's education should be more prioritized because it can interfere with the idea of early marriage. Awareness can also be raised by social activities since the improvement of social conditions and reduction of social deprivation can increase the age of mother at first birth.

3.
Open Forum Infect Dis ; 2(4): ofv155, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26719843

RESUMO

Background. Both endothelin receptor type B ([ETBR], a G protein-coupled receptor that mediates the vascular effects of the potent vasoconstrictor endothelin-1) and human cytomegalovirus ([HCMV], a ubiquitous herpesvirus) have been implicated in the pathogenesis of cardiovascular disease (CVD). The effects of HCMV infection on ETBR expression are unknown. We hypothesized that HCMV may contribute to the pathogenesis of CVD via ETBR modulation. Methods. Human CMV effects on ETBR were studied in vitro in endothelial cells (ECs) and smooth muscle cells (SMCs) and ex vivo in human carotid plaque tissue specimens. Expression of ETBR and viral immediate-early were quantified using quantitative polymerase chain reaction. Functional consequences after ETBR blockade in ECs were examined by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide proliferation, wound healing, tube formation, and flow adhesion assays. Results. Human CMV is capable of upregulating both ETBR mRNA and protein expression in ECs and SMCs. The ETBR was also abundantly expressed in ECs, foam cells, and SMCs, and, more importantly, in HCMV-positive cells in human carotid plaques. Endothelin receptor type B blockade led to decreased proliferation and reduced tumor necrosis factor α-mediated leukocyte recruitment in both uninfected and HCMV-infected ECs. Direct HCMV infection was antimigratory and antiangiogenic in ECs. Conclusions. Human CMV may contribute to CVD via ETBR induction.

4.
Carcinogenesis ; 35(1): 145-54, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23978378

RESUMO

A lack of gap junctional intercellular communication (GJIC) is common in cancer. Many oncogenic viruses have been shown to downregulate the junctional protein connexin 43 (Cx43) and reduce GJIC. Human cytomegalovirus (HCMV) is a ubiquitous, species-specific betaherpesvirus that establishes life-long latency after primary infection. It encodes two viral gene products, immediate early (IE) proteins IE1 and IE2, which are crucial in viral replication and pathogenesis of many diseases. Emerging evidence demonstrates that HCMV DNA and proteins are highly prevalent in glioblastoma multiforme (GBM) and in other tumors, but HCMV's role in tumorigenesis remains obscure. In the present study, we examined the effects of HCMV infection on Cx43 expression and GJIC as well as the viral mechanism mediating the effects in human GBM cells and tissue samples. We found that HCMV downregulated Cx43 protein, resulting in disruption of functional GJIC as assayed by fluorescent dye transfer assay. We show that both HCMV-IE72 and IE86 mediate downregulation of Cx43 by silencing RNA targeting either IE72 or IE86 coupled with ganciclovir. This finding was further validated by transfection with expression vectors encoding IE72 or IE86, and we show that viral-mediated Cx43 depletion involved proteasomal degradation. Importantly, we also observed that the Cx43 protein levels and IE staining correlated inversely in 10 human GBM tissue specimens. Thus, HCMV regulates Cx43 expression and GJIC, which may contribute to gliomagenesis.


Assuntos
Neoplasias do Sistema Nervoso Central/virologia , Conexina 43/metabolismo , Infecções por Citomegalovirus/metabolismo , Junções Comunicantes/metabolismo , Glioblastoma/virologia , Proteínas Imediatamente Precoces/metabolismo , Transativadores/metabolismo , Neoplasias do Sistema Nervoso Central/patologia , Conexina 43/genética , Citomegalovirus/metabolismo , Citomegalovirus/patogenicidade , Infecções por Citomegalovirus/complicações , Infecções por Citomegalovirus/virologia , Fibroblastos/metabolismo , Fibroblastos/virologia , Glioblastoma/patologia , Humanos , Proteínas Imediatamente Precoces/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Transativadores/genética , Células Tumorais Cultivadas
5.
Immunobiology ; 218(8): 1034-40, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23434301

RESUMO

CD4 T cells are important regulators of the immune system and are vital for mounting a strong immune response against viral infections. Human cytomegalovirus (HCMV) is known to be a strong modulator of the innate as well as adaptive immune responses. In this study, we found that HCMV directly inhibited proliferation of CD4 T cells and rendered them unresponsive to immunological stimuli. This effect was not observed when CD4 T cells were treated with herpes simplex virus-1/2 or measles virus. When stimulated with phytohemagglutinin, concanavalin A, or phorbol myristate acetate, HCMV-treated T cells were unable to proliferate, revealing an ability of HCMV to inhibit CD4 T cell response. Furthermore, HCMV also prevented proliferation of leukemic T-cell lines. HCMV-treated CD4 T cells expressed the activation markers CD45RO and CD69, were not apoptotic and produced decreased levels of the cytokines IL-4, IFN-γ and TNF-α, compared to untreated controls. The inhibitory effect of HCMV on CD4 T cell proliferation was not mediated by HCMV gH, gB or other immunogenic glycoproteins, since intravenous immunoglobulins or gB- or gH-specific neutralizing antibodies did not prevent the suppression of T-cell proliferation. Our observations show that HCMV inhibits CD4 T cell function with potential clinical consequences for both humoral and cell-mediated immune responses.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Proliferação de Células/efeitos dos fármacos , Infecções por Citomegalovirus/imunologia , Citomegalovirus/imunologia , Ativação Linfocitária/imunologia , Anticorpos Antivirais/imunologia , Antígenos CD/biossíntese , Antígenos de Diferenciação de Linfócitos T/biossíntese , Linhagem Celular Tumoral , Concanavalina A , Infecções por Citomegalovirus/virologia , Herpesvirus Humano 1/imunologia , Herpesvirus Humano 2/imunologia , Humanos , Interferon gama/biossíntese , Interleucina-4/biossíntese , Células K562 , Lectinas Tipo C/biossíntese , Antígenos Comuns de Leucócito/biossíntese , Leucócitos Mononucleares/imunologia , Macrófagos/imunologia , Vírus do Sarampo/imunologia , Fito-Hemaglutininas , Acetato de Tetradecanoilforbol , Fator de Necrose Tumoral alfa/biossíntese
6.
J Clin Invest ; 121(10): 4043-55, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21946257

RESUMO

Medulloblastomas are the most common malignant brain tumors in children. They express high levels of COX-2 and produce PGE2, which stimulates tumor cell proliferation. Human cytomegalovirus (HCMV) is prevalent in the human population and encodes proteins that provide immune evasion strategies and promote oncogenic transformation and oncomodulation. In particular, HCMV induces COX-2 expression; STAT3 phosphorylation; production of PGE2, vascular endothelial growth factor, and IL-6; and tumor formation in vivo. Here, we show that a large proportion of primary medulloblastomas and medulloblastoma cell lines are infected with HCMV and that COX-2 expression, along with PGE2 levels, in tumors is directly modulated by the virus. Our analysis indicated that both HCMV immediate-early proteins and late proteins are expressed in the majority of primary medulloblastomas. Remarkably, all of the human medulloblastoma cell lines that we analyzed contained HCMV DNA and RNA and expressed HCMV proteins at various levels in vitro. When engrafted into immunocompromised mice, human medulloblastoma cells induced expression of HCMV proteins. HCMV and COX-2 expression correlated in primary tumors, cell lines, and medulloblastoma xenografts. The antiviral drug valganciclovir and the specific COX-2 inhibitor celecoxib prevented HCMV replication in vitro and inhibited PGE2 production and reduced medulloblastoma tumor cell growth both in vitro and in vivo. Ganciclovir did not affect the growth of HCMV-negative tumor cell lines. These findings imply an important role for HCMV in medulloblastoma and suggest HCMV as a novel therapeutic target for this tumor.


Assuntos
Neoplasias Encefálicas/virologia , Citomegalovirus/isolamento & purificação , Meduloblastoma/virologia , Adulto , Animais , Antivirais/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Celecoxib , Linhagem Celular Tumoral , Criança , Pré-Escolar , Inibidores de Ciclo-Oxigenase 2/farmacologia , Citomegalovirus/efeitos dos fármacos , Citomegalovirus/patogenicidade , Citomegalovirus/fisiologia , Dinoprostona/biossíntese , Feminino , Ganciclovir/análogos & derivados , Ganciclovir/farmacologia , Humanos , Lactente , Masculino , Meduloblastoma/tratamento farmacológico , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , Pirazóis/farmacologia , Sulfonamidas/farmacologia , Valganciclovir , Replicação Viral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , Adulto Jovem
7.
Int J Mol Med ; 28(6): 977-83, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21894430

RESUMO

Cell replacement and gene therapy using neural stem cells (NSCs) have been widely touted as a promising treatment for CNS diseases including brain tumors. Histone deacetylase (HDAC) inhibitors have been used to explore mechanisms behind the lineage-specific differentiation of NSCs and as modulators of gene therapy. We have used the human embryonic midbrain stem cell line NGC-407 and the HDAC inhibitor 4-phenylbutyrate (4-PB) to investigate the differentiation from epigenetic perspectives. NGC-407 cells can differentiate into both neurons and glial cells, evidenced by morphological characteristics as well as up-regulation of the respective markers ß-tubulin III and glial fibrillary acidic protein (GFAP) and simultaneous down-regulation of the NSC-marker nestin. Genomic DNA extracted from the differentiating cells was globally more methylated than that of the proliferating cells. The differentiating cells showed increased expression of the de novo DNA methyltransferase DNMT3B along with strong immunoreactivity in the cell nuclei. When these cells were treated with 4-PB, both the astrocytic and the neuronal differentiation phenotypes were suppressed, which paralleled a substantially weakened DNMT3B immunoreactivity in the cell nuclei. Importantly, 4-PB treatment preserves the immature phenotype of these differentiating cells as indicated by Western blot analysis and immunocytochemical analyses of the NSC markers, nestin and CD133. Nestin becomes entirely degraded 5 days after induction of differentiation, but upon exposure to 4-PB, some of the differentiating cells retain the integrity of nestin and concurrently, CD133 is also up-regulated. Taken together, the data suggests that HDAC activity is necessary for human embryonic NSC differentiation.


Assuntos
Biomarcadores/análise , Neoplasias Encefálicas/terapia , Diferenciação Celular , DNA (Citosina-5-)-Metiltransferases/metabolismo , Células-Tronco Embrionárias/citologia , Terapia Genética/métodos , Histona Desacetilases/metabolismo , Mesencéfalo/citologia , Fenilbutiratos/farmacologia , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Linhagem Celular , Proliferação de Células , DNA (Citosina-5-)-Metiltransferases/genética , Células-Tronco Embrionárias/efeitos dos fármacos , Células-Tronco Embrionárias/metabolismo , Proteína Glial Fibrilar Ácida/análise , Proteína Glial Fibrilar Ácida/biossíntese , Inibidores de Histona Desacetilases/farmacologia , Humanos , Proteínas de Filamentos Intermediários/análise , Proteínas de Filamentos Intermediários/biossíntese , Mesencéfalo/metabolismo , Proteínas do Tecido Nervoso/análise , Proteínas do Tecido Nervoso/biossíntese , Nestina , Neuroglia/citologia , Neuroglia/metabolismo , Neurônios/citologia , Neurônios/metabolismo , Fenótipo , Transplante de Células-Tronco , Tubulina (Proteína)/análise , Tubulina (Proteína)/biossíntese , DNA Metiltransferase 3B
8.
Mol Cell Biol ; 31(19): 4119-28, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21791605

RESUMO

Histone deacetylase inhibitors (HDACi) are promising antitumor drugs acting through reactivation of silenced tumor suppressor genes. Several HDACi are currently in clinical trials both for hematological and solid tissue malignancies. Cooperative action of HDACi and DNA methylation inhibitors (DNMTi) has been reported, making combined treatment an attractive choice for cancer therapy. There is some evidence that synergistic effects of HDACi and DNMTi are achieved by their action on common targets, including DNA methyltransferase 1 (DNMT1). To further analyze this interaction, we investigated the effect of the HDACi trichostatin A on global and gene-specific DNA methylation and applied methods with single molecule sensitivity, confocal laser scanning microscopy with avalanche photodiode detectors (APD imaging) and fluorescence correlation spectroscopy (FCS), to study its effect on the nuclear dynamics of DNMT1 in live cells. Our data show that trichostatin A treatment reduces global DNA methylation and the DNMT1 protein level and alters DNMT1 nuclear dynamics and interactions with chromatin. The mechanisms underlying these effects are apparently distinct from the mechanisms of action of the DNMT inhibitor 5-azacytidine. Our study sheds light on the molecular mechanisms underlying the synergistic action of HDACi and DNMTi and may also help to define improved policies for cancer treatment.


Assuntos
Núcleo Celular/metabolismo , DNA (Citosina-5-)-Metiltransferases/metabolismo , Metilação de DNA , Inibidores de Histona Desacetilases/metabolismo , Histona Desacetilases/metabolismo , Azacitidina/metabolismo , Linhagem Celular Tumoral , Cromatina/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , DNA (Citosina-5-)-Metiltransferase 1 , DNA (Citosina-5-)-Metiltransferases/genética , Histona Desacetilases/genética , Humanos , Ácidos Hidroxâmicos/metabolismo , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo
9.
Neuro Oncol ; 12(6): 549-58, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20154339

RESUMO

The prognosis for malignant gliomas remains poor, and new treatments are urgently needed. Targeted suicide gene therapy exploits the enzymatic conversion of a prodrug, such as a nucleoside analog, into a cytotoxic compound. Although this therapeutic strategy has been considered a promising regimen for central nervous system (CNS) tumors, several obstacles have been encountered such as inefficient gene transfer to the tumor cells, limited prodrug penetration into the CNS, and inefficient enzymatic activity of the suicide gene. We report here the cloning and successful application of a novel thymidine kinase 1 (TK1) from the tomato plant, with favorable characteristics in vitro and in vivo. This enzyme (toTK1) is highly specific for the nucleoside analog prodrug zidovudine (azidothymidine, AZT), which is known to penetrate the blood-brain barrier. An important feature of toTK1 is that it efficiently phosphorylates its substrate AZT not only to AZT monophosphate, but also to AZT diphosphate, with excellent kinetics. The efficiency of the toTK1/AZT system was confirmed when toTK1-transduced human glioblastoma (GBM) cells displayed a 500-fold increased sensitivity to AZT compared with wild-type cells. In addition, when neural progenitor cells were used as delivery vectors for toTK1 in intracranial GBM xenografts in nude rats, substantial attenuation of tumor growth was achieved in animals exposed to AZT, and survival of the animals was significantly improved compared with controls. The novel toTK1/AZT suicide gene therapy system in combination with stem cell-mediated gene delivery promises new treatment of malignant gliomas.


Assuntos
Genes Transgênicos Suicidas/genética , Terapia Genética/métodos , Glioma/genética , Glioma/terapia , Solanum lycopersicum/enzimologia , Timidina Quinase/genética , Animais , Linhagem Celular Tumoral , Glioma/patologia , Humanos , Solanum lycopersicum/genética , Proteínas de Plantas/genética , Proteínas de Plantas/uso terapêutico , Ratos , Ratos Nus , Timidina Quinase/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
10.
Neuro Oncol ; 12(1): 19-27, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20150364

RESUMO

Glioblastoma (GB) is the most common malignant brain tumor in adults. It has limited treatment opportunities and is almost exclusively fatal. Owing to the central role the insulin-like growth factor-1 receptor (IGF-1R) plays in malignant cells, it has been suggested as a target for anticancer therapy including GB. The cyclolignan picropodophyllin (PPP) inhibits IGF-1R without affecting the highly homologous insulin receptor. Here, we show that PPP inhibits growth of human GB cell lines along with reduced phosphorylation of IGF-1R and AKT. In vivo, PPP-treatment causes dramatic tumor regression not only in subcutaneous xenografts but also in intracerebral xenografts, indicating passage of PPP across the blood-brain barrier.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Glioblastoma/tratamento farmacológico , Podofilotoxina/análogos & derivados , Receptor IGF Tipo 1/antagonistas & inibidores , Animais , Apoptose/efeitos dos fármacos , Western Blotting , Linhagem Celular Tumoral , Humanos , Imunoprecipitação , Camundongos , Camundongos SCID , Podofilotoxina/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto
11.
J Trace Elem Med Biol ; 22(1): 17-23, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18319136

RESUMO

Recent data indicate that A(1) adenosine receptor (A(1)AR) density is increased in a zone surrounding human and experimental gliomas. On the contrary, tumor tissue and adjacent brain tissue show low to intermediate A(1)AR densities. In order to assess whether changes in A(1)AR expression are indicating further processes of a chemical reorganization of the peritumoral zone, we investigated element concentrations and distribution patterns of copper and zinc in six human glioblastoma multiforme (GBM) specimens by laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS). Uranium and lead were used as external standards. Copper and zinc levels were increased in a peritumoral zone corresponding to the region of elevated A(1)AR density. They showed a lower density in the solid tumor in comparison to surrounding brain tissue, although the cellular density was higher within GBM. Our findings suggest that the immediate vicinity of GBM is characterized by increased levels of copper and zinc supporting the view that higher A(1)AR density surrounding GBM is not an isolated alteration of peritumoral tissue but an indicator of complex changes in the vicinity of infiltrative tumors. Further research is needed to explore the pathophysiological consequences of altered peritumoral element distribution.


Assuntos
Neoplasias Encefálicas/química , Cobre/análise , Glioblastoma/química , Zinco/análise , Química Encefálica , Humanos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Urânio/química
12.
Exp Cell Res ; 313(13): 2958-67, 2007 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-17555745

RESUMO

Enzyme prodrug therapy using neural progenitor cells (NPCs) as delivery vehicles has been applied in animal models of gliomas and relies on gap junction communication (GJC) between delivery and target cells. This study investigated the effects of histone deacetylase (HDAC) inhibitors on GJC for the purpose of facilitating transfer of therapeutic molecules from recombinant NPCs. We studied a novel immortalized midbrain cell line, NGC-407 of embryonic human origin having neural precursor characteristics, as a potential delivery vehicle. The expression of gap junction protein connexin 43 (Cx43) was analyzed by western blot and immunocytochemistry. While Cx43 levels were decreased in untreated differentiating NGC-407 cells, the HDAC inhibitor 4-phenylbutyrate (4-PB) increased Cx43 expression along with increased membranous deposition in both proliferating and differentiating cells. Simultaneously, Ser 279/282-phosphorylated form of Cx43 was declined in both culture conditions by 4-PB. The 4-PB effect in NGC-407 cells was verified by using HNSC.100 human neural progenitors and Trichostatin A. Improved functional GJC is of imperative importance for therapeutic strategies involving intercellular transport of low molecular-weight compounds. We show here an enhancement by 4-PB, of the functional GJC among NGC-407 cells, as well as between NGC-407 and human glioma cells, as indicated by increased fluorescent dye transfer.


Assuntos
Sistemas de Liberação de Medicamentos , Inibidores Enzimáticos/farmacologia , Junções Comunicantes/efeitos dos fármacos , Inibidores de Histona Desacetilases , Neurônios/enzimologia , Neurônios/transplante , Pró-Fármacos/administração & dosagem , Transplante de Células-Tronco , Comunicação Celular/efeitos dos fármacos , Diferenciação Celular , Linhagem Celular , Proliferação de Células , Conexina 43/análise , Conexina 43/metabolismo , Junções Comunicantes/química , Humanos , Ácidos Hidroxâmicos/farmacologia , Fenilbutiratos/farmacologia , Células-Tronco/enzimologia
13.
Biochem Biophys Res Commun ; 324(1): 8-14, 2004 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-15464975

RESUMO

Malignant glioma patients have a dismal prognosis with an urgent need of new treatment modalities. Previously developed gene therapies for brain tumors showed promising results in experimental animal models, but failed in clinical trials due to low transfection rates and insufficient expression of the transgene in tumor cells, as well as low bystander killing effects. We have previously shown that the histone deacetylase inhibitor 4-phenylbutyrate (4-PB) enhances gap junction communication between glioma cells in culture. In this study, we demonstrate an activation of recombinant HSV-tk gene expression, and a dramatic enhancement of gap junction-mediated bystander killing effect by administration of the HSV-tk prodrug ganciclovir together with 4-PB. These findings that 4-PB potentiates "suicide gene" expression as well as enhances gap junctional communication and bystander killing of tumor cells justify further testing of this paradigm as an adjunct to suicide gene therapy of malignant gliomas.


Assuntos
Neoplasias Encefálicas/metabolismo , Efeito Espectador/fisiologia , Glioma/metabolismo , Inibidores de Histona Desacetilases , Fenilbutiratos/metabolismo , Simplexvirus/enzimologia , Timidina Quinase/metabolismo , Animais , Anti-Inflamatórios/metabolismo , Anti-Inflamatórios/farmacologia , Antivirais/metabolismo , Antivirais/uso terapêutico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/terapia , Efeito Espectador/efeitos dos fármacos , Linhagem Celular Tumoral , Técnicas de Cocultura , Conexina 43/metabolismo , Ganciclovir/metabolismo , Ganciclovir/uso terapêutico , Junções Comunicantes/metabolismo , Regulação Neoplásica da Expressão Gênica , Terapia Genética , Glioma/genética , Glioma/terapia , Ácido Glicirretínico/metabolismo , Ácido Glicirretínico/farmacologia , Histona Desacetilases/metabolismo , Humanos , Fenilbutiratos/farmacologia , Ratos , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Timidina Quinase/genética
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