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1.
Clin Cancer Res ; 21(17): 4004-13, 2015 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-26023083

RESUMO

PURPOSE: To identify the miRNA regulators of C-X-C motif chemokine receptor 4 (CXCR4) and the underlying mechanism as well as the therapeutic and prognostic values in human glioblastoma (GBM). EXPERIMENTAL DESIGN: miRNA profile analyses and bioinformatics predictions were used to identify the mediators of CXCR4, which were confirmed by luciferase reporter assay, Western blot assay and immunohistochemistry. The effects of miR-663 on CXCR4-mediated GBM malignancy were investigated by gain-of-function experiments. Orthotopic xenografts derived from constitutive or induced miR-663-expressing GBM cells were used to determine the antitumor effects of miR-663 and CXCR4-specific antagonist AMD3100. Bivariate correlation analyses were used to examine the correlation of miR-663 and CXCR4 levels in glioma. The prognostic values of miR-663 and CXCR4 were examined in 281 cases of astrocytic glioma from our hospital and 476 cases of GBM from The Cancer Genome Atlas database using the multivariate Cox regression analysis and Kaplan-Meier analysis. RESULTS: miR-663 negatively regulated CXCR4 expression by targeting its coding sequence in GBM and compromised the proliferative and invasive capacities of GBM cells induced by CXCR4 overexpression. Constitutive or induced miR-663 overexpression combined with CXCR4 antagonist AMD3100 suppressed orthotopic GBM growth and prolonged tumor-bearing mice survival. Clinically, miR-663 and CXCR4 were inversely correlated in GBM and composed a valuable biomarker set in predicting the outcomes of GBM patients. CONCLUSIONS: miR-663 negatively regulated CXCR4 to inhibit its oncogenic effect. Combination of miR-663 and CXCR4 can serve as a valuable prognostic biomarker set as well as molecular targets for therapeutic intervention of GBM.


Assuntos
Neoplasias Encefálicas/genética , Glioblastoma/genética , MicroRNAs/genética , Receptores CXCR4/genética , Animais , Sequência de Bases , Sítios de Ligação , Biomarcadores Tumorais , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Transformação Celular Neoplásica/genética , Modelos Animais de Doenças , Feminino , Regulação Neoplásica da Expressão Gênica , Glioblastoma/mortalidade , Glioblastoma/patologia , Camundongos , MicroRNAs/química , Prognóstico , Interferência de RNA , RNA Mensageiro/química , RNA Mensageiro/genética , Receptores CXCR4/antagonistas & inibidores , Receptores CXCR4/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
3.
Clin Cancer Res ; 20(7): 1803-13, 2014 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-24523440

RESUMO

PURPOSE: To determine the prognostic significance of miR-663 in glioblastoma, its effect in tumor progression, and the underlying mechanism. EXPERIMENTAL DESIGN: Specimens from 256 cases of patients with glioma, including 239 patients with follow-up information, were used to analyze the association between miR-663 and patients' prognosis by Kaplan-Meier and multivariate Cox regression analyses. The effects of miR-663 on glioblastoma cell proliferation and invasion were examined both in vitro and in vivo. Bioinformatics prediction and signal network analysis were applied to identify the putative targets of miR-663, which were further verified by luciferase reporter assay, rescue experiments as well as the immunohistochemistry (IHC) and Western blotting examination of downstream effectors. Quantitative reverse transcriptase PCR (qRT-PCR) and IHC were applied to investigate the clinical association between miR-663 and its target in human glioblastoma specimens. RESULTS: miR-663 was inversely correlated with glioma grades but positively correlated with patients' survival. Furthermore, two distinct subgroups of patients with glioblastoma with different prognoses were identified on the basis of miR-663 expression in our specimens and that from The Cancer Genome Atlas (TCGA) database. Overexpression of miR-663 significantly suppressed the proliferation and invasion of glioblastoma cells in vitro and in vivo. Mechanistically, we discovered PIK3CD as a direct target of miR-663 and found that phosphorylated AKT and three key downstream effectors of PIK3CD, i.e., CCND1, MMP2, and MMP7, were downregulated by miR-663 overexpression. Moreover, PIK3CD was inversely correlated with miR-663 in glioblastoma specimens and predicted poor prognosis of patients with glioblastoma. CONCLUSION: miR-663 is a novel prognostic biomarker and a potential therapeutic candidate for glioblastoma.


Assuntos
Neoplasias Encefálicas/genética , Classe I de Fosfatidilinositol 3-Quinases/genética , Glioblastoma/genética , MicroRNAs/genética , Adulto , Idoso , Animais , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Regulação Neoplásica da Expressão Gênica , Genes Supressores de Tumor , Glioblastoma/patologia , Humanos , Estimativa de Kaplan-Meier , Masculino , Camundongos , Pessoa de Meia-Idade , Invasividade Neoplásica/genética , Prognóstico , Modelos de Riscos Proporcionais , Ensaios Antitumorais Modelo de Xenoenxerto
4.
Neuro Oncol ; 15(12): 1595-603, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24203894

RESUMO

BACKGROUND: Long noncoding RNA Hox transcript antisense intergenic RNA (HOTAIR) has been characterized as a negative prognostic factor in breast and colon cancer patients. The clinical significance and function of HOTAIR in glioma remains unclear. METHODS: We analyzed the clinical significance of HOTAIR in 3 different glioma cohorts with gene expression data, including correlation with tumor grade, prognosis, and molecular subtype. The function of HOTAIR in glioma was explored by performing gene set enrichment analysis and in vitro and in vivo experiments. RESULTS: HOTAIR expression was closely associated with glioma grade and poor prognosis. Multivariate Cox regression analysis revealed that HOTAIR was an independent prognostic factor in glioblastoma multiforme patients. HOTAIR expression correlated with glioma molecular subtype, including those of The Cancer Genome Atlas. HOTAIR was preferentially expressed in the classical and mesenchymal subtypes compared with the neural and proneural subtypes. A gene set enrichment analysis designed to show gene set differences between patients with high and low HOTAIR expression indicated that HOTAIR expression was associated with gene sets involved in cell cycle progression. HOTAIR reduction induced colony formation suppression, cell cycle G0/G1 arrest, and orthotopic tumor growth inhibition. CONCLUSION: Our data establish that HOTAIR is an important long noncoding RNA that primarily serves as a prognostic factor for glioma patient survival, as well as a biomarker for identifying glioma molecular subtypes, a critical regulator of cell cycle progression.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias Encefálicas/genética , Glioma/genética , Mesoderma/patologia , RNA Longo não Codificante/genética , Adulto , Animais , Western Blotting , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/patologia , Estudos de Casos e Controles , Ciclo Celular , Proliferação de Células , Feminino , Seguimentos , Perfilação da Expressão Gênica , Glioma/mortalidade , Glioma/patologia , Humanos , Masculino , Mesoderma/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Gradação de Tumores , Análise de Sequência com Séries de Oligonucleotídeos , Prognóstico , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Taxa de Sobrevida , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
6.
CNS Neurosci Ther ; 18(7): 573-83, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22630347

RESUMO

AIMS: MicroRNA-21 (miR-21) expression is increased in many types of human malignancy, including glioma. Recent studies report that miR-21 regulates cell invasion by targeting RECK, however, the underlying transcriptional regulation of miR-21 in glioma cells remains elusive. RESULTS: Here, we identify a positive correlation between miR-21 expression and pathological grade in glioma tissues. We demonstrate that ß-catenin pathway regulates miR-21 expression in human umbilical vein endothelial cell and glioma cells, and that this regulation is signal transducer and activator of transcription 3 (STAT3)-dependent. Further, chromatin immunoprecipitation and luciferase reporter analysis demonstrate that miR-21 is controlled by an upstream promoter containing a conserved STAT3 binding site. Notably, knockdown of miR-21-inhibited cell invasion by increasing RECK expression and decreased tumor growth in a xenograft model. CONCLUSION: These data provide compelling evidence that ß-catenin regulation of miR-21 via STAT3 plays a role in glioma cell invasion and proliferation and indicate that STAT3 is a potential therapeutic target for glioma intervention.


Assuntos
Proteínas Ligadas por GPI/metabolismo , Regulação Neoplásica da Expressão Gênica , Glioma/metabolismo , MicroRNAs/metabolismo , Fator de Transcrição STAT3/fisiologia , beta Catenina/fisiologia , Animais , Linhagem Celular Tumoral , Regulação para Baixo/genética , Proteínas Ligadas por GPI/genética , Técnicas de Silenciamento de Genes/métodos , Marcação de Genes/métodos , Glioma/genética , Glioma/patologia , Humanos , Camundongos , Camundongos Nus , MicroRNAs/biossíntese , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , Veias Umbilicais/citologia , Veias Umbilicais/metabolismo , Regulação para Cima/genética , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
7.
Zhonghua Bing Li Xue Za Zhi ; 40(7): 454-9, 2011 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-22088371

RESUMO

OBJECTIVES: To investigate the relationship between the expression of miR-218 and CDK6 in glioma cells, and their biological impacts on the tumor cell proliferation and apoptosis. METHODS: Expression levels of miR-218 as well as CDK6 and Ki-67 proteins were analyzed in 60 cases of gliomas with various grades and 10 control brain tissue samples by tissue microarray, locked oligonucleotide probe in situ hybridization and immunohistochemistry. Glioblastoma multiform cell line (U87MG) was transfected with miR-218 mimics (mimics group) and a control sequence (control group), followed by qRT-PCR detection of miR-218 and immunocytochemical stain of CDK6 and Ki-67, respectively. Single cell gel electrophoresis was used to detect the presence of apoptotic cell. RESULTS: The miR-218 labeling indexes (LI) were statistically different (P<0.05) among all groups including control (22.45 +/- 0.59) and various glioma groups (grades I - II 4.00 +/- 1.07, grade III 1.87 +/- 1.06 and grade IV 0.94 +/- 0.78, respectively). The CDK6 LI of the four groups was 7.25 +/- 1.20, 16.71 +/- 0.80, 24.43 +/- 0.62 and 32.05 +/- 0.43, respectively. Significant differences existed between the control group and the glioma groups, and between grade IV and grades I - II glioma groups (P<0.01). Ki-67 positive cell densities of the above four groups (0.00 +/- 0.00, 9.30 +/- 3.48, 31.15 +/- 9.44 and 60.15 +/- 13.60) were significantly different from one and another (P<0.01). The expression of miR-218 negatively correlated with CDK-6 LI (r = -0.480, P<0. 01) and Ki-67 positive cell density (r = - 0.534, P<0.01), while the latter two positively correlated with each other (r = 0.530, P<0.01). U87MG transfection experiment showed that the miR-218 level of the mimics group was significantly higher than that of the control group (P<0.01). CDK6 and Ki-67 LI of the mimics group (14.74 +/- 1.19 and 30.88 +/- 3.31) were significantly lower than those of the control group (79.06 +/- 2.07 and 64.94 +/- 3.96, P<0.01), whilst its apoptotic index (AI) (68.44 +/- 7.05) was significantly higher than that of the control group (13.04 +/- 0.97, P<0.01). CONCLUSIONS: The expression level of miR-218 is an important reference indicator for the assessment of the grade of gliomas. An aberrant decrease of its expression may lead to an increase of the CDK6 expression and proliferative activity of giloma cells. Introducing exogenous miR-218 may effectively down-regulate the CDK6 expression, inhibit cell proliferation and induce apoptosis of malignant giloma cells. These findings imply that miR-218 may serve as a therapeutic agent against malignant glioma.


Assuntos
Apoptose , Neoplasias Encefálicas/patologia , Proliferação de Células , Quinase 6 Dependente de Ciclina/metabolismo , Glioma/patologia , MicroRNAs/metabolismo , Adolescente , Adulto , Astrocitoma/metabolismo , Astrocitoma/patologia , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Criança , Ependimoma/metabolismo , Ependimoma/patologia , Feminino , Glioblastoma/metabolismo , Glioblastoma/patologia , Glioma/metabolismo , Humanos , Antígeno Ki-67/metabolismo , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Oligodendroglioma/metabolismo , Oligodendroglioma/patologia , Transfecção , Adulto Jovem
8.
Zhonghua Bing Li Xue Za Zhi ; 39(10): 686-90, 2010 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-21176536

RESUMO

OBJECTIVES: To investigate the pharmacological effects of azidothymidine (AZT) on p33ING1b expression, senescence and apoptosis of TJ905 glioblastoma cells. METHODS: TJ905 cells were treated with AZT at a serial concentrations of 50, 100 and 200 µmol/L. Semi-quantitative RT-PCR and cytochemical staining of senescence related-galactosidase (sß-Gal) were used to evaluate the expression of p33ING1b mRNA and to label the senescent cells at the 1st, 3rd and 6th generations, respectively. In situ cell death detection and single cell gel electrophoresis were used to detect the apoptosis at the 3rd and 6th generations. RESULTS: AZT induced the expression of p33ING1b mRNA and senescence of the tumor cells of the 1st generation in a dosage and time dependent manner. At the 6th generation, the relative amount of p33ING1b RT-PCR product (1.44±0.23) and sß-Gal labeling index of 200 µmol/L group (45.62±6.74) were significantly higher than those of the 1st (0.95±0.13 and 7.82±2.40) and the 3rd generation cells (1.35±0.23, 26.27±7.17) of the same group, and cells of the same generation in the 50 µmol/L (0.85±0.24, 27.37±6.41) and 100 µmol/L groups (1.23±0.34, 35.49±5.12, P<0.01). There was a significant positive correlation between the p33ING1b mRNA expression and the labeling index of sß-Gal. Pro-apoptotic effects of AZT became obvious at the 6th generation. CONCLUSION: AZT upregulates the expression of p33ING1b, a possible mechanism in regulating senescence and apoptosis of the TJ905 cells.


Assuntos
Apoptose/efeitos dos fármacos , Senescência Celular/efeitos dos fármacos , Glioblastoma/patologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Zidovudina/farmacologia , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Glioblastoma/metabolismo , Humanos , Proteína 1 Inibidora do Crescimento , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas Nucleares/genética , RNA Mensageiro/metabolismo , Inibidores da Transcriptase Reversa/administração & dosagem , Inibidores da Transcriptase Reversa/farmacologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteínas Supressoras de Tumor/genética , Zidovudina/administração & dosagem
9.
Zhonghua Bing Li Xue Za Zhi ; 39(9): 606-10, 2010 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-21092588

RESUMO

OBJECTIVE: To investigate the relationship between chromosomal genomic DNA imbalance in medulloblastoma (MB), and the age and gender. METHODS: The gains and losses of chromosomal genomic DNA in 16 MBs were analyzed using comparative genomic hybridization. RESULTS: The gains and(or) losses were found in 15 of the 16 cases. There was not significant difference (P > 0.05) between the total gains (10/16) and losses (11/16). Both of their differences had also no significance between different age and gender groups (P > 0.05). In 15 cases with gains and(or) losses, single-, two-, three- and multi-chromosome genomic DNA imbalances were 3/15, 4/15, 1/15 and 7/15 respectively. Eleven gain zones (+5q, +6q, +7q, +11q, +15q, +17p, +17q, +19q, +20q, +21q, +Xp) and twenty-five loss zones (-1p, -1q, -2p, -2q, -3q, -4p, -6p, -6q, -8p, -8q, -10p, -10q, -11p, -14q, -16p, -16q, -17p, -18p, -18q, -19p, -19q, -20p, -20q, -Xp, -Xq) were detected in those tumors. +7q (6/16), +17q (6/16), -14q (5/16) and -10q (3/16) were the most frequent, but -14q only occurred in the cases of > 10-year-old. CONCLUSIONS: Most MBs have chromosomal genomic DNA imbalances. The frequent imbalance zones are mainly at the long arms of some chromosomes. +7q, +17q, -14q and -10q correlate closely to development of the tumors. -14q is important factor to result in MBs of > 10-year-old group. MB has possibly different molecular genetics subtype.


Assuntos
Neoplasias Cerebelares/genética , Aberrações Cromossômicas , Deleção Cromossômica , Meduloblastoma/genética , Adolescente , Adulto , Fatores Etários , Criança , Pré-Escolar , Hibridização Genômica Comparativa , DNA de Neoplasias/genética , Feminino , Humanos , Masculino , Fatores Sexuais , Adulto Jovem
10.
J Neurooncol ; 98(3): 329-40, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20035367

RESUMO

Our previous study demonstrated that SEPT7 was downregulated at mRNA level in human gliomas. This study is to further examine the expression of SEPT7 in glioma samples and characterizes its role on cell cycle progression and growth of glioma cells. mRNA and protein expression of SEPT7 were detected by RT-PCR, immunohistochemical staining, and western blot analysis in human glioma specimens and normal brain tissues. A pcDNA3-SEPT7 expression plasmid was constructed and transfected into human glioblastoma cell line U251, and cell proliferation and apoptosis were examined. The growth of established U251 and TJ905 subcutaneous xenograft gliomas was measured in nude mice treated with pcDNA3-SEPT7 and U251 xenograft tumors treated with SEPT7 siRNA. SEPT7 expression is negatively correlated with the increase of glioma grade. Overexpression of SEPT7 is able to inhibit cell proliferation and arrest cell cycle progression in the G0/G1 phase both in vitro and in vivo. Knocking down further the already low endogenous expression of SEPT7 in U251 xenograft tumors with siRNA leads to faster tumor growth compared with control tumors. This study demonstrates that SEPT7 is involved in gliomagenesis and suppresses glioma cell growth.


Assuntos
Neoplasias Encefálicas/metabolismo , Proteínas do Citoesqueleto/metabolismo , Proteínas de Ligação ao GTP/metabolismo , Regulação Neoplásica da Expressão Gênica/fisiologia , Glioma/metabolismo , Análise de Variância , Animais , Apoptose/fisiologia , Encéfalo/metabolismo , Neoplasias Encefálicas/patologia , Caspase 3/metabolismo , Ciclo Celular/fisiologia , Proteínas de Ciclo Celular , Linhagem Celular Tumoral , Proliferação de Células , Proteínas do Citoesqueleto/genética , Modelos Animais de Doenças , Citometria de Fluxo/métodos , Proteínas de Ligação ao GTP/genética , Proteína Glial Fibrilar Ácida/metabolismo , Glioma/patologia , Humanos , Marcação In Situ das Extremidades Cortadas/métodos , Camundongos , Camundongos Nus , Transplante de Neoplasias/mortalidade , Transplante de Neoplasias/patologia , Antígeno Nuclear de Célula em Proliferação/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/farmacologia , Septinas , Fatores de Tempo , Análise Serial de Tecidos/métodos , Transfecção/métodos
13.
Zhonghua Bing Li Xue Za Zhi ; 38(3): 148-52, 2009 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-19575847

RESUMO

OBJECTIVE: To investigate genomic DNA imbalances in ependymomas (EDMs) and their correlations with the tumor histological types, grades, locations, patients' gender and age. METHODS: Chromosomal gains and losses in 16 cases of EDM were analyzed using comparative genomic hybridization. RESULTS: Chromosomal regional gain and loss were found in 15 and 13 of 16 EDM cases respectively including totally 24 regional gains and 19 regional losses in all the tumors studied. Both regional gains and losses were mostly seen in myxopapillary EDMs (MPE, WHO grade I), more commonly seen in cellular EDMs (CE, WHO grade II) and tanycytic EDMs (TE, WHO grade II) than in anaplastic EDMs (AE, WHO grade III). Some of the regional gains and losses appeared only in one subtype of MPE, CE, TE and AE cases resulting in development of specific imbalance profiles of certain subtype in these cases. MPE, CE and TE often had +7. Chromosomal +5 occurred only in MPE and CE, and -22q was only seen in CE and TE. AE frequently had +1q, but none had +5, +7, -4q, -19q and -22q. The frequencies of any regional gain or loss were not affected by patients' genders (P > 0.05). Chromosomal +1q and +7p happened predominantly in intracranial EDMs with an averagely onset age of

Assuntos
Neoplasias Encefálicas/genética , Aberrações Cromossômicas , Ependimoma/genética , Neoplasias da Medula Espinal/genética , Adolescente , Adulto , Idoso , Neoplasias Encefálicas/classificação , Neoplasias Encefálicas/patologia , Criança , Hibridização Genômica Comparativa , DNA de Neoplasias/genética , Ependimoma/classificação , Ependimoma/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias da Medula Espinal/classificação , Neoplasias da Medula Espinal/patologia , Adulto Jovem
14.
Zhonghua Bing Li Xue Za Zhi ; 38(3): 183-8, 2009 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-19575855

RESUMO

OBJECTIVE: To investigate the pharmacological effects and underlying mechanism of azidothymidine (AZT) on human glioblastoma cells in vitro. METHODS: The telomerase activity of human glioblastoma TJ905 cells was determined by TRAP assay after 24 hrs' incubation with 50, 100, 200 micromol/L AZT and control vehicle solution. Colony formation efficiencies of the cells were recorded. Cells of the 1st, 3rd and 6th generations were harvested, followed by evaluations of cyclin A protein expression by Western blot, cell cycle distribution by flow cytometry, apoptotic level by single cell gel electrophoresis and proliferation index by Ki-67 immunocytochemical staining. RESULTS: AZT inhibited telomerase activity of TJ905 cells. Cyclin A expression levels in the cells treated with 50 and 100 micromol/L AZT were significantly lower than controls (P < 0.01), and down-regulation of the expression was in a dose- and time-dependent manner. Compared with controls, G(0)/G(1) phase cells were obviously decreased (P < 0.05 approximately 0.01) and S phase cells significantly increased (P < 0.05 approximately 0.01) after treatment with 50, 100 and 200 micromol/L AZT. The cell numbers of G(0)/G(1) and S phases at the 1st generation of above three treated groups changed in a dose-dependent manner, whereas S phase cells increases in all AZT treatment groups and G(0)/G(1) phase cell decrease in group treated with 50 micromol/L AZT were also in a time-dependent manner. Both the apoptotic cells of the 1st and 6th generations of all AZT treatment groups were significantly more than controls (P < 0.05 approximately 0.01), their numbers of the 6th generations of the three groups increased with AZT concentration (P < 0.05 approximately 0.01), and all of them were more than the 1st and 3rd generations of the same dosage group (P < 0.05 approximately 0.01). Colony formation efficiencies and Ki-67 labeling indexes of the three AZT treatment groups were distinctly lower than controls (P < 0.01), and they were also decreased with the elevation of AZT concentration and/or the elongation of the incubating time. The difference of any above parameter had no significance among the 1st, 3rd and 6th generations of control group (P > 0.05). CONCLUSION: AZT blocks S/G(2) conversion of TJ905 cells by inhibition of telomerase activity and cyclin A expression, leading to an enhancement of apoptosis and suppression of cell proliferation.


Assuntos
Proliferação de Células/efeitos dos fármacos , Glioblastoma , Telomerase/metabolismo , Zidovudina/farmacologia , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Ciclina A/metabolismo , Relação Dose-Resposta a Droga , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Antígeno Ki-67/metabolismo , Inibidores da Transcriptase Reversa/administração & dosagem , Inibidores da Transcriptase Reversa/farmacologia , Zidovudina/administração & dosagem
15.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 23(3): 330-2, 2006 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-16767677

RESUMO

OBJECTIVE: To construct the NLS(ING1)-GFP vector, transfer it into MRC-5 cells and establish a cell model expressing NLS (ING1)-GFP fusion protein. METHODS: Firstly, cDNA fragment of nuclear locating sequence (NLS) of inhibitor of growth-1 gene (ING1) was gained by RT-PCR and inserted into multi-clone site of pEGFP-C1 to construct the NLS (ING1)-GFP expression vector. Then the vector was used to transfect the MRC-5 cells to observe the subcellular signal localization of green fluorescence protein (GFP). RESULTS: We successfully constructed the expressing vector of NLS (ING1)-GFP fusion protein. After transferring the fusion expressing vector into MRC-5 cells, we observed that green fluorescence signal located in the cell nucleus. However, the green fluorescence signal located in the cytoplasm in MRC-5 cells transfected with pEGFP-C1 control only expressing GFP. CONCLUSION: In living cells, physiologically p33 ING1b locates absolutely in nucleus. The p33(ING1b) NLS plays a decisive role in the transporting process of subcellular localization.


Assuntos
Vetores Genéticos/genética , Proteínas de Fluorescência Verde/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas Nucleares/genética , Proteínas Recombinantes de Fusão/genética , Proteínas Supressoras de Tumor/genética , Sequência de Bases , Linhagem Celular , Proteínas de Fluorescência Verde/metabolismo , Humanos , Proteína 1 Inibidora do Crescimento , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Microscopia de Fluorescência , Dados de Sequência Molecular , Proteínas Nucleares/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Transfecção , Proteínas Supressoras de Tumor/metabolismo
16.
Zhonghua Bing Li Xue Za Zhi ; 35(3): 165-70, 2006 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-16630506

RESUMO

OBJECTIVE: To investigate the effect of z-DEVD-fmk, a caspase-3 inhibitor on the neuronal apoptosis in ischemia-reperfusion region (IRR) of rat cerebral cortex. METHODS: Rats prepared by middle cerebral artery occlusion and reperfusion were used as the research model. The animals were divided into A group (untreated), B group (DMSO control) and C group (treated with z-DEVD-fmk). Before reperfusion, z-DEVD-fmk (7 microg/kg) was injected into the ischemic side of ventriculus cerebri of C group rats. The expression and activation of caspase-3, expression and cleavage of poly (ADP-ribose) polymerase (PARP), and apoptotic neurons in the temporal-parietal cortex IRRs (SPAB method) of all the rats were studied using Western blotting, in situ apoptotic detection (TUNEL method) and immunohistochemistry. RESULTS: In the cerebral IRRs of A, B, C groups reperfused for 1 h and 24 h, the quantities of caspase-3 precursor were 16.7 +/- 3.0, 11.5 +/- 3.0 and 47.5 +/- 3.5, and 76.1 +/- 3.5, 71.3 +/- 6.4 and 88.2 +/- 5.5, respectively; the caspase-3 fragments (12,000) 8.2 +/- 2.3, 9.4 +/- 1.2 and 4.3 +/- 1.6, and 59.0 +/- 6.3, 60.5 +/- 7.2 and 17.3 +/- 2.8, respectively; the PARP 12.6 +/- 3.0, 13.9 +/- 2.0 and 53.7 +/- 4.1, and 67.5 +/- 8.6, 61.1 +/- 6.6 and 93.6 +/- 4.1, respectively; the PARP fragments (24,000) 6.0 +/- 0.7, 6.6 +/- 1.2, 3.6 +/- 1.1, and 27.4 +/- 2.6, 25.8 +/- 3.2, 12.1 +/- 2.8 (relative quantity, x+/- s); the densities of apoptotic neurons 83.3 +/- 7.5, 84.3 +/- 5.7 and 45.7 +/- 4.0, and 197.4 +/- 11.8, 185.2 +/- 11.2 and 99.1 +/- 5.8 (cell number/0.1 mm(2), x+/- s). These results showed that in the cerebral IRRs of both A and B groups, all caspase-3 expression and activation, PARP expression and cleavage, and neuronal apoptosis were increased relevantly along with prolongation of the reperfusion time (P < 0.05 - 0.001). At each time point of the reperfusion, caspase-3 activation, PARP cleavage and neuronal apoptosis in the cerebral IRR of C group were significantly less than those of the former two groups (P < 0.05 - 0.001). The variations of the 5 parameters of A, B and C groups correlated positively with one another (r = 0.630 - 0.942, P < 0.01). The cells expressing PARP were mainly neurons in the cerebral IRRs of all the animals, but the difference of their number was not distinct among the 3 groups. CONCLUSIONS: It is an important mechanism resulting in apoptosis of the injured neurons in the cerebral IRR that caspase-3 expression and activation abnormally increased by the reperfusion have more PARP rapidly inactivated by over-cleavage. z-DEVD-fmk may decrease PARP cleavage by inhibiting activity and auto-activation of caspase-3, and prevent the injured neurons from apoptosis.


Assuntos
Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Córtex Cerebral/efeitos dos fármacos , Oligopeptídeos/farmacologia , Traumatismo por Reperfusão/fisiopatologia , Animais , Inibidores de Caspase , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Inibidores de Cisteína Proteinase/farmacologia , Infarto da Artéria Cerebral Média/complicações , Masculino , Neurônios/efeitos dos fármacos , Poli(ADP-Ribose) Polimerases/metabolismo , Distribuição Aleatória , Ratos , Ratos Wistar , Traumatismo por Reperfusão/etiologia , Traumatismo por Reperfusão/metabolismo
18.
Zhonghua Bing Li Xue Za Zhi ; 32(3): 215-9, 2003 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-12882685

RESUMO

OBJECTIVE: To investigate the relationship between expressions of ING1 gene and genes of human telomerase reverse transcriptase (hTERT) and telomerase-associated protein 1 (hTP1) in human gliomas. METHODS: The expressions of ING1 mRNA and p33(ING1) protein, hTERT mRNA and protein, and hTP1 mRNA and protein in seventy human glioma specimens with different malignant grades were studied using in situ hybridization and immunohistochemistry. RESULTS: All of the 70 gliomas collected expressed hTP1 mRNA and protein and among them, 62 (88.6%) and 58 (82.9%) out of 70 expressed hTERT mRNA and protein respectively. The quantities of the four kinds of positive cells were correlated positively with one another (r = 0.758 - 0.882, P < 0.000 5), and all of them were significantly fewer in gliomas of WHO grade I - II than in grade III gliomas and the most in grade IV gliomas (P < 0.05 approximately 0.01). 66 (94.3%) and 62 (88.6%) out of 70 gliomas expressed ING1 mRNA and p33(ING1) protein respectively. The quantities of their positive cells were also correlated positively with each other (r = 0.831, P < 0.000 5), but the positive cells were more in gliomas of WHO grade I - II than in grade III gliomas and the fewest in grade IV gliomas (P < 0.01). The quantities of positive cells of ING1 mRNA and p33(ING1) protein were correlated negatively with those of hTERT mRNA and protein as well as hTP1 mRNA and protein respectively (r = -0.211 to -0.384, P < 0.05 approximately 0.001). CONCLUSIONS: The results suggest that all of the parameters concerned are valuable in evaluating the biological behavior of gliomas. In glioma cells, overexpressions of hTERT and hTP1 genes might be significant in inhibiting the expression of ING1 gene. The abnormal expressions of the three genes play possibly the important roles in the development and malignant progression of gliomas.


Assuntos
Proteínas de Transporte/genética , Glioma/genética , Proteínas de Membrana Transportadoras , Proteínas/genética , Telomerase/genética , Adolescente , Adulto , Idoso , Proteínas de Transporte/análise , Proteínas de Ciclo Celular , Proteínas de Ligação a DNA , Feminino , Genes Supressores de Tumor , Glioma/metabolismo , Humanos , Imuno-Histoquímica , Hibridização In Situ , Proteína 1 Inibidora do Crescimento , Peptídeos e Proteínas de Sinalização Intracelular , Masculino , Pessoa de Meia-Idade , Proteínas Nucleares , RNA Mensageiro/análise , Telomerase/análise , Proteínas Supressoras de Tumor
19.
Zhonghua Wai Ke Za Zhi ; 41(10): 770-2, 2003 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-14766053

RESUMO

OBJECTIVE: To investigate the differential gene expression of ependymomas. METHODS: Four fresh samples of ependymomas and 1 of normal brain tissue were collected during operation. The extracted total RNAs were converted as (32)P tagged cDNA probes, which were then hybridized with the Atlas Human Cancer Array, producing the array based hybridization maps following the protocol provided with the kit. A set of special software was applied to the analysis and RT-PCR was performed to test the result. RESULT: In comparison with the normal brain tissue, there were 31 upregulated gene and 1 downregulated gene in ependymomas, most of which were firstly found to be differentially expressed in this kind of tumor. CONCLUSION: The discrepancy of gene expression profiles between ependymomas and normal brain tissues is highly put through and effectively detected with cDNA array, which provides new information for the further research on the molecular mechanisms of this lesion.


Assuntos
Neoplasias Encefálicas/genética , Ependimoma/genética , Perfilação da Expressão Gênica , Análise de Sequência com Séries de Oligonucleotídeos , Encéfalo/metabolismo , Humanos , Reação em Cadeia da Polimerase Via Transcriptase Reversa
20.
Ai Zheng ; 21(10): 1085-9, 2002 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-12508649

RESUMO

BACKGROUND & OBJECTIVE: There is great signification to classify the molecular pathogenesis of gliomas. Gene chip is able to profile the gene expression of tumors, which may become a new method for studying molecular pathology of tumors. The cDNA was used in order to detect the differences in gene expression profiles of different types of gliomas. METHODS: cDNA probes tagged with 32P were converted from total RNA extracted from 4 samples of 3 different pathological types, including oligodendrogliomas, anaplastic astrocytomas and ependymomas, and one sample of normal human brain tissue as well, which were then hybridized to the Atlas array. After autoradiography, the gene expression profiles were analyzed with the special software and by the cluster analysis. RESULTS: As compared to the normal brain tissue, the number of differential expressed genes in these tumor samples ranging from 11 to 118 was found. These 4 samples could be divided into 3 kinds of types when 107 differential expressed genes were selected to be as the cluster analysis index. This result was in accordance with the neuropathological diagnosis. CONCLUSION: cDNA array is able to profile gene expression in different types of gliomas. Combined with the bioinformational method, we may further obtain useful information about molecular pathology of gliomas.


Assuntos
Perfilação da Expressão Gênica , Glioma/genética , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Regulação Neoplásica da Expressão Gênica , Glioma/patologia , Humanos , RNA Neoplásico/genética , RNA Neoplásico/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
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