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1.
Cell Death Differ ; 23(4): 565-75, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25909886

RESUMO

Cell cycle proteins are important regulators of diverse cell fate decisions, and in this capacity have pivotal roles in neurogenesis and brain development. The mechanisms by which cell cycle regulation is integrated with cell fate control in the brain and other tissues are poorly understood, and an outstanding question is whether the cell cycle machinery regulates fate decisions directly or instead as a secondary consequence of proliferative control. Identification of the genes targeted by E2 promoter binding factor (E2f) transcription factors, effectors of the pRb/E2f cell cycle pathway, will provide essential insights into these mechanisms. We identified the promoter regions bound by three neurogenic E2f factors in neural precursor cells in a genome-wide manner. Through bioinformatic analyses and integration of published genomic data sets we uncovered hundreds of transcriptionally active E2f-bound promoters corresponding to genes that control cell fate processes, including key transcriptional regulators and members of the Notch, fibroblast growth factor, Wnt and Tgf-ß signaling pathways. We also demonstrate a striking enrichment of the CCCTC binding factor transcription factor (Ctcf) at E2f3-bound nervous system-related genes, suggesting a potential regulatory co-factor for E2f3 in controlling differentiation. Finally, we provide the first demonstration of extensive tissue specificity among E2f target genes in mammalian cells, whereby E2f3 promoter binding is well conserved between neural and muscle precursors at genes associated with cell cycle processes, but is tissue-specific at differentiation-associated genes. Our findings implicate the cell cycle pathway as a widespread regulator of cell fate genes, and suggest that E2f3 proteins control cell type-specific differentiation programs by regulating unique sets of target genes. This work significantly enhances our understanding of how the cell cycle machinery impacts cell fate and differentiation, and will importantly drive further discovery regarding the mechanisms of cell fate control and transcriptional regulation in the brain, as well as in other tissues.


Assuntos
Fatores de Transcrição E2F/metabolismo , Regulação da Expressão Gênica , Proteínas Repressoras/metabolismo , Elementos de Resposta , Transcrição Gênica , Animais , Fator de Ligação a CCCTC , Fatores de Transcrição E2F/genética , Camundongos , Camundongos Mutantes , Especificidade de Órgãos/genética , Proteínas Repressoras/genética , Retinoblastoma/genética , Retinoblastoma/metabolismo
2.
Eur J Pain ; 18(5): 659-70, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-25493301

RESUMO

Background: Pulsed radiofrequency (PRF) has been widely used to treat chronic pain, but the effectiveness and mechanisms in preventing early neuropathic pain have not been well explored. Even fewer knowledge is available in its impact on glia-mediated nociceptive sensitization. This study aims to elucidate the modulation of PRF on nerve injury-induced pain development and activation of spinal mitogen-activated protein kinases (MAPKs). Methods: In a rat spinal nerve ligation (SNL) model, a low-volt PRF treatment was applied to the L5 dorsal root ganglion after nerve injury. Nociceptive behaviours were measured by von Frey and heat withdrawal tests at multiple time points. MAPK activations, including p-ERK and p-p38, as well as TNF-á level in the spinal dorsal horn were assessed and the cell types that expressed MAPK activation were identified by double immuno fluorescence staining.Results: We found that SNL promptly induced neuropathic pain in the affected hind limb for over 1 week as well as increased p-ERK and p-p38 in the spinal dorsal horn. PRF significantly attenuated SNL-induced mechanical allodynia and thermal hyperalgesia for 5­7 days. PRF also inhibited ERK and p38 activations, which were found majorly located within neurons and microglia, respectively. Besides, PRF significantly suppressed expression of TNF-á in the spinal dorsal horn throughout the course. Conclusions: Low-volt PRF significantly ameliorated SNL-induced acute pain. Inferentially, PRF may inhibit spinal sensitization by down-regulating spinal MAPK activations and activation-mediated cytokine release.We demonstrated that early PRF treatment in acute nerve injury helps to ameliorate neuropathic pain development.


Assuntos
Hiperalgesia/prevenção & controle , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Neuralgia/enzimologia , Neuralgia/terapia , Tratamento por Radiofrequência Pulsada , Nervos Espinhais/enzimologia , Nervos Espinhais/efeitos da radiação , Doença Aguda , Animais , Comportamento Animal , Modelos Animais de Doenças , Regulação para Baixo/efeitos da radiação , Ativação Enzimática/efeitos da radiação , Gânglios Espinais/efeitos da radiação , Imuno-Histoquímica , Ligadura , Masculino , Neuroglia/efeitos da radiação , Nociceptividade/efeitos da radiação , Medição da Dor , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Nervos Espinhais/lesões , Fator de Necrose Tumoral alfa/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
3.
Eur J Clin Microbiol Infect Dis ; 33(9): 1653-9, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24715153

RESUMO

Chronic fatigue syndrome (CFS) is a complex disorder accompanied by unexplainable persistent fatigue, in which several etiological factors exist, such as viral infections. Using the National Health Insurance Research Database (NHIRD) of Taiwan, this study evaluated the association between herpes zoster (HZ) infection and the risk of CFS, and examined the possibility of patients developing postviral fatigue effects, including the possibility of developing other unexplainable chronic fatigue conditions. In this prospective cohort study using the NHIRD, we identified 9,205 patients with HZ infection [ICD-9 (International Classification of Disease, Ninth Revision), code 053] and 36,820 patients without HZ infection (non-HZ) from 2005 to 2007, and followed up to the end of 2010. The incidence rate of CFS was higher in the HZ cohort than in the non-HZ cohort (4.56 vs. 3.44 per 1,000 person-years), with an adjusted hazard ratio of 1.29 [95 % confidence interval (CI) = 1.09-1.53]. It was shown that the risk of CFS without comorbidity for each patient increased from 1.25- to 1.36-fold between the CFS and non-CFS cohorts; with long-term follow-up, the HZ cohort showed a significantly higher cumulative incidence rate of developing CFS than the non-HZ patients. We propose that patients with chronic fatigue might exist in a subset of patients that would be associated with HZ infection. The actual mechanism of development of CFS that is attributed to HZ infection remains unclear. The findings of this population cohort study provide pivotal evidence of postviral fatigue among patients with HZ infection.


Assuntos
Síndrome de Fadiga Crônica/epidemiologia , Herpes Zoster/complicações , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Medição de Risco , Taiwan/epidemiologia , Adulto Jovem
4.
Oncogene ; 28(1): 31-40, 2009 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-18806829

RESUMO

Endometrioid adenocarcinoma is the most frequent form of endometrial cancer, usually developing in pre- and peri-menopausal women. beta-catenin abnormalities are common in endometrioid type endometrial carcinomas with squamous differentiation. To investigate the role of beta-catenin (Ctnnb1) in uterine development and tumorigenesis, mice were generated which expressed a dominant stabilized beta-catenin or had beta-catenin conditionally ablated in the uterus by crossing the PR(Cre) mouse with the Ctnnb1(f(ex3)/+) mouse or Ctnnb1(f/f) mouse, respectively. Both of the beta-catenin mutant mice have fertility defects and the ability of the uterus to undergo a hormonally induced decidual reaction was lost. Expression of the dominant stabilized beta-catenin, PR(cre/+)Ctnnb1(f(ex3)/+), resulted in endometrial glandular hyperplasia, whereas ablation of beta-catenin, PR(cre/+)Ctnnb1(f/f), induced squamous cell metaplasia in the murine uterus. Therefore, we have demonstrated that correct regulation of beta-catenin is important for uterine function as well as in the regulation of endometrial epithelial differentiation.


Assuntos
Transformação Celular Neoplásica/genética , Hiperplasia Endometrial/genética , Endométrio/crescimento & desenvolvimento , beta Catenina/fisiologia , Animais , Diferenciação Celular/genética , Proliferação de Células , Transformação Celular Neoplásica/patologia , Modelos Animais de Doenças , Hiperplasia Endometrial/patologia , Endométrio/patologia , Feminino , Infertilidade Feminina/genética , Camundongos , Camundongos Mutantes , beta Catenina/genética
5.
Br J Radiol ; 81(966): 490-8, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18487389

RESUMO

The aim of this study was to evaluate the outcome and prognosticators for patients with resectable head and neck cancer (RHNC) undergoing definitive concurrent chemotherapy and radiotherapy (CCRT). In total, 110 RHNC patients receiving definitive CCRT to defer radical surgery were enrolled. Radiotherapy was given as either 2 Gy once daily with 70 Gy, or 1.2 Gy twice daily with 74.4 Gy. Chemotherapy involved the administration of 5-fluorouracil and cisplatin in two concomitant and two post-radiotherapy adjuvant cycles. 3 months after CCRT, MRI was performed to evaluate the response and determine further treatment plans. Survival outcome was calculated by the Kaplan-Meier method. Log-rank test and Cox regression analyses were used to estimate the significance of prognosticators. 4-year local-regional control, distant metastasis-free survival, disease-free survival and overall survival rates were 76.1%, 85.6%, 67.5% and 53.2%, respectively. Local recurrence (odds ratio = 4.09; p < 0.0001) and T3/T4 stage (odds ratio = 2.34; p = 0.01) were the independent factors associated with poor survival. T stage (odds ratio = 3.29; p = 0.03) and/or remission status on post-CCRT MRI (odds ratio = 7.22; p < 0.0001) were significantly associated with local control, distant metastasis-free survival and disease-free survival. 13 of 20 patients with imaging residuum had local recurrence, compared with 12 of 89 with complete remission (4-year local control rate of 27% vs 86%; p < 0.0001). Post-CCRT MRI may thus be used to predict the chance of a successful non-surgical approach.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/radioterapia , Imageamento por Ressonância Magnética/normas , Adulto , Idoso , Quimioterapia Adjuvante/métodos , Cisplatino/administração & dosagem , Feminino , Fluoruracila/administração & dosagem , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Recidiva Local de Neoplasia/diagnóstico , Prognóstico , Radioterapia Adjuvante/métodos , Estudos Retrospectivos
6.
Exp Neurol ; 211(2): 588-92, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18440506

RESUMO

Stroke is the leading cause of adult disability in the United States. To date there is no satisfactory treatment for stroke once neuronal damage has occurred. Human adult bone marrow-derived somatic cells (hABM-SC) represent a homogenous population of CD49c/CD90 co-positive, non-hematopoietic cells that have been shown to secrete therapeutically relevant trophic factors and to support axonal growth in a rodent model of spinal cord injury. Here we demonstrate that treatment with hABM-SC after ischemic stroke in adult rats results in recovery of forelimb function on a skilled motor test, and that this recovery is positively correlated with increased axonal outgrowth of the intact, uninjured corticorubral tract. While the complete mechanism of repair is still unclear, we conclude that enhancement of structural neuroplasticity from uninjured brain areas is one mechanism by which hABM-SC treatment after stroke leads to functional recovery.


Assuntos
Axônios/fisiologia , Transplante de Medula Óssea , Isquemia Encefálica/cirurgia , Transplante de Células-Tronco Mesenquimais , Plasticidade Neuronal/fisiologia , Recuperação de Função Fisiológica/fisiologia , Adulto , Animais , Transplante de Medula Óssea/métodos , Isquemia Encefálica/fisiopatologia , Isquemia Encefálica/reabilitação , Humanos , Masculino , Transplante de Células-Tronco Mesenquimais/métodos , Ratos , Ratos Long-Evans , Células Estromais/transplante
7.
Annu Rev Physiol ; 66: 647-63, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-14977417

RESUMO

The lung is a complex organ consisting of numerous cell types that function to ensure sufficient gas exchange to oxygenate the blood. In order to accomplish this function, the lung must be exposed to the external environment and at the same time maintain a homeostatic balance between its function in gas exchange and the maintenance of inflammatory balance. During the past two decades, as molecular methodologies have evolved with the sequencing of entire genomes, the use of in vivo models to elucidate the molecular mechanisms involved in pulmonary physiology and disease have increased. The mouse has emerged as a potent model to investigate pulmonary physiology due to the explosion in molecular methods that now allow for the developmental and tissue-specific regulation of gene transcription. Initial efforts to manipulate gene expression in the mouse genome resulted in the generation of transgenic mice characterized by the constitutive expression of a specific gene and knockout mice characterized by the ablation of a specific gene. The utility of these original mouse models was limited, in many cases, by phenotypes resulting in embryonic or neonatal lethality that prevented analysis of the impact of the genetic manipulation on pulmonary biology. Second-generation transgenic mouse models employ multiple strategies that can either activate or silence gene expression thereby providing extensive temporal and spatial control of the experimental parameters of gene expression. These highly regulated mouse models are intended to serve as a foundation for further investigation of the molecular basis of human disease such as tumorigenesis. This review describes the principles, progress, and application of systems that are currently employed in the conditional regulation of gene expression in the investigation of lung cancer.


Assuntos
Modelos Animais de Doenças , Engenharia Genética , Neoplasias Pulmonares/genética , Animais , Genes de Troca , Camundongos , Camundongos Knockout/genética , Camundongos Transgênicos/genética
8.
Neuroscience ; 114(1): 55-67, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12207954

RESUMO

Corticosterone is the main adrenal glucocorticoids induced by stress in rats. Therapeutic use of high concentration of synthetic glucocorticoids in clinical treatment of spinal cord injury suggests that pharmacological action of glucocorticoids might be beneficial for nerve repair. In this article we cultured axotomized rat dorsal root ganglion neurons to investigate the effects of corticosterone and a glutamate receptor agonist kainic acid on neurite outgrowth. Our results revealed a synergistic effect of corticosterone and kainic acid in promoting neurite outgrowth when applied as early as one and two days in vitro, but not effective at three and four days in vitro. In addition, applied corticosterone and kainic acid were neurotoxic at three and four days in vitro but not at one and two days in vitro. The minimal concentrations of corticosterone and kainic acid to be effective were 10 microM and 1 mM, respectively. The neurotrophic effect of corticosterone and kainic acid was attenuated by the receptor tyrosine kinase A (TrkA) inhibitor AG-879. Western blot analysis and immunocytochemical studies revealed an increase of expressions of both TrkA and growth-associated protein GAP-43 in dorsal root ganglion neurons with combined treatment of corticosterone and kainic acid. Immunocytochemistry showed that corticosterone+kainic acid increase nerve growth factor immunoreactivity in dorsal root ganglion neurites and enhance GAP-43 immunointensity in dorsal root ganglion neurons. These results suggest that the neurotrophic effect of glucocorticoids on axonal regeneration might require facilitation of excitatory stimulation at an early stage of nerve injury, and nerve growth factor may mediate a growth signaling to accomplish the effect.


Assuntos
Corticosterona/farmacologia , Gânglios Espinais/efeitos dos fármacos , Gânglios Espinais/crescimento & desenvolvimento , Ácido Caínico/farmacologia , Regeneração Nervosa/efeitos dos fármacos , Neuritos/efeitos dos fármacos , Neurônios Aferentes/efeitos dos fármacos , Animais , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Células Cultivadas , Relação Dose-Resposta a Droga , Interações Medicamentosas/fisiologia , Quimioterapia Combinada , Proteína GAP-43/efeitos dos fármacos , Proteína GAP-43/metabolismo , Gânglios Espinais/metabolismo , Cones de Crescimento/efeitos dos fármacos , Cones de Crescimento/metabolismo , Cones de Crescimento/ultraestrutura , Imuno-Histoquímica , Masculino , Regeneração Nervosa/fisiologia , Neuritos/metabolismo , Neuritos/ultraestrutura , Neurônios Aferentes/citologia , Neurônios Aferentes/metabolismo , Ratos , Ratos Sprague-Dawley , Receptor de Fator de Crescimento Neural/antagonistas & inibidores , Receptor de Fator de Crescimento Neural/metabolismo , Receptor trkA/efeitos dos fármacos , Receptor trkA/metabolismo , Receptores de AMPA/metabolismo , Receptores de Ácido Caínico/metabolismo , Tirfostinas/farmacologia
9.
Int J Oncol ; 20(5): 891-6, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-11956580

RESUMO

Prostate cancer (CaP), the most common malignancy in American men, presents its greatest challenge to clinicians when the cancer progresses to the hormone-refractory state. In the present investigation, we studied the combined effects of interferon (IFN) and onconase, each of which has reported antitumor activity, on growth and specific protein expression in JCA-1 cells. Cells were treated for up to 3 days with 1 and 5 microg/ml onconase, with and without concurrent addition of IFN-beta(ser) (10(3) IU/ml). Cell count and viability, and de novo RNA and protein synthesis were determined. Expression and subcellular distribution of STAT-1 were also assessed by immunoblot analysis. JCA-1 cells treated for 3 days with IFN or onconase showed a 15-30% reduction in cell proliferation, which was increased to 42-51% with both agents. Analysis of [35S]methionine incorporation into cells confirmed a more pronounced inhibitory effect elicited by IFN-beta and onconase; IFN-beta and 1 microg/ml onconase each decreased de novo protein synthesis by 23-25%, while the combination resulted in 59% suppression. Similar studies using incorporation of [3H]uridine into RNA yielded less significant effects. Further investigation using pre-labeled cellular RNA and proteins showed that either agent or their combination did not affect the turnover of macromolecules. To test whether the antiproliferative effects of IFN-beta and onconase were correlated with one or more specific gene changes, expression of an IFN-modulated protein, STAT-1, was determined. Both phosphorylated and unphosphorylated forms of STAT-1 and its subcellular distribution in the nucleus and cytoplasm, were increased 3-fold by IFN-beta. The IFN-elicited elevation of STAT-1 was not additionally augmented by onconase but was reduced 20-25% when onconase was simultaneously present as IFN-beta. These data show that the overall changes in STAT-1 did not correlate with the reduction in cell growth and the suppression of de novo protein/RNA synthesis elicited by these two agents, and imply that other target proteins are likely to be involved in the combined effects of IFN-beta and onconase in JCA-1 cells.


Assuntos
Proteínas de Ligação a DNA/biossíntese , Interferon beta/uso terapêutico , Ribonucleases/uso terapêutico , Transativadores/biossíntese , Divisão Celular/efeitos dos fármacos , Humanos , Immunoblotting , Masculino , Fosforilação , Neoplasias da Próstata/tratamento farmacológico , Biossíntese de Proteínas , Fator de Transcrição STAT1 , Fatores de Tempo , Células Tumorais Cultivadas
10.
Mol Cell Biol ; 21(23): 8056-67, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11689696

RESUMO

We have previously demonstrated that overexpression of Cdc25B in transgenic mice resulted in mammary gland hyperplasia and increased steroid hormone responsiveness. To address how Cdc25B enhances the hormone responsiveness in mammary glands, we showed that Cdc25B stimulates steroid receptor-dependent transcription in transient transfection assays and in a cell-free assay with chromatin templates. Surprisingly, the effect of Cdc25B on steroid receptors is independent of its protein phosphatase activity in vitro. The direct interactions of Cdc25B with steroid receptors, on the other hand, were evidenced in in vivo and in vitro assays, suggesting the potential direct contribution of Cdc25B on the steroid receptor-mediated transcription. In addition, p300/CBP-associated factor and CREB binding protein were shown to interact and synergize with Cdc25B and further enhance its coactivation activity. Thus, we have uncovered a novel function of Cdc25B that serves as a steroid receptor coactivator in addition to its role as a regulator for cell cycle progression. This dual function might likely contribute to its oncogenic action in breast cancer.


Assuntos
Mama/metabolismo , Proteínas de Ciclo Celular/metabolismo , Receptores de Esteroides/metabolismo , Proteínas de Saccharomyces cerevisiae , Fosfatases cdc25/metabolismo , Acetiltransferases/metabolismo , Animais , Proteína de Ligação a CREB , Ciclo Celular/fisiologia , Proteínas de Ciclo Celular/farmacologia , Linhagem Celular , Sistema Livre de Células/metabolismo , Ciclina D1/metabolismo , Ativação Enzimática/fisiologia , Feminino , Regulação da Expressão Gênica/fisiologia , Histona Acetiltransferases , Humanos , Proteínas Nucleares/metabolismo , Ratos , Receptores Androgênicos/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Glucocorticoides/metabolismo , Receptores de Progesterona/metabolismo , Transativadores/metabolismo , Fatores de Transcrição , Transcrição Gênica/efeitos dos fármacos , Transcrição Gênica/fisiologia , Fosfatases cdc25/farmacologia , Fatores de Transcrição de p300-CBP
11.
Histol Histopathol ; 16(4): 1135-41, 2001 10.
Artigo em Inglês | MEDLINE | ID: mdl-11642733

RESUMO

The pineal gland is part of the neuroendocrine system that modulates immune functions. Because the gland is outside the blood-brain barrier, it is accessible to direct feedback from circulating cytokines that affect the synthesis and secretion of melatonin. Recent studies have suggested that intrinsic immunoregulatory cytokines mediate these neuro-immune interactions under the control of sympathetic innervation to the pineal. This study focused on the expression of transforming growth factor-beta1 (TGF-beta1) and interleukin-6 (IL-6), two cytokines that have important regulatory functions on both neurons and immune cells. Northern blot RNA analysis showed that TGF-beta1, but not IL-6, was expressed in freshly dissected rat pineal glands from neonatal age (1-day-old) into adults. Immunocytochemistry for TGF-beta1 in adult glands revealed localization of this protein in astrocyte-like cells. The sympathetic neurotransmitter norepinephrine (NE) increased transcript levels for both TGF-beta1 and IL-6 in adult pineal organ cultures. The effect of NE on IL-6 expression was not found in dispersed cell cultures established from neonatal pineal glands. The immunoregulatory molecule interleukin-1beta (IL-1beta) up-regulated the expression of both IL-6 and TGF-beta1 in adult pineal organ cultures, but not in neonate pineal organ cultures. These findings suggest that TGF-beta1 and IL-6 have intrinsic regulatory roles in the pineal gland and that both neural and immune factors are important mechanisms of regulation.


Assuntos
Agonistas alfa-Adrenérgicos/farmacologia , Interleucina-1/farmacologia , Interleucina-6/biossíntese , Norepinefrina/farmacologia , Glândula Pineal/metabolismo , Fator de Crescimento Transformador beta/biossíntese , Animais , Células Cultivadas , Imuno-Histoquímica , Microscopia Confocal , Técnicas de Cultura de Órgãos , Sistema Nervoso Parassimpático/fisiologia , Glândula Pineal/efeitos dos fármacos , RNA Mensageiro/biossíntese , Ratos , Ratos Sprague-Dawley , Fator de Crescimento Transformador beta1
12.
Proc Natl Acad Sci U S A ; 98(22): 12426-31, 2001 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-11606780

RESUMO

Employing a cell-free chromatin transcription system that recapitulates progesterone receptor (PR)-mediated transcription in vivo, we have investigated further the coactivator functions of steroid receptor coactivator-1 (SRC-1) in terms of its functional domains as well as cooperation with other coactivators in PR transactivation. By analyzing wild-type and mutant SRC-1 with liganded PR in the chromatin transcription system in vitro, the basic helix-loop-helix/Per-Arnt-Sim domain, the p300-binding domain, and the carboxyl-terminal region (containing the PR-binding site) of SRC-1 were shown to be important for PR transactivation. Although in context of a synthetic promoter its histone acetyltransferase activity was nonessential for PR-mediated transcription, SRC-1 was observed to act synergistically with p300 to enhance PR transactivation from chromatin. Moreover, SRC-1 and p300 were found to function cooperatively to increase the efficiency of productive transcription initiation and reinitiation. Further analysis of synergism between SRC-1 and p300 revealed an obligatory "sequential" recruitment of SRC-1 and p300 to liganded PR. Efficient recruitment of p300 required the presence of SRC-1. In addition, functional analysis of SRC-2 and SRC-3 coactivators indicated that the SRC family modulated PR transactivation from chromatin by a similar mechanism.


Assuntos
Cromatina/metabolismo , Proteínas Nucleares/fisiologia , Receptores de Progesterona/fisiologia , Proteínas de Saccharomyces cerevisiae , Sarcosina/análogos & derivados , Transativadores/fisiologia , Fatores de Transcrição/fisiologia , Transcrição Gênica , Acetiltransferases/metabolismo , Sítios de Ligação , Histona Acetiltransferases , Humanos , Coativador 1 de Receptor Nuclear , Coativador 2 de Receptor Nuclear , Coativador 3 de Receptor Nuclear , Proteínas Oncogênicas , Sarcosina/farmacologia , Ativação Transcricional
13.
Chem Biol Interact ; 137(2): 139-54, 2001 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-11551530

RESUMO

Toxicokinetics of trichloroethylene (TCE) and tetrachloroethylene (PER) in culture medium and their toxicity to CHO-K1 cells were investigated by employing an in vitro vapor exposure system. Cells were cultured in a 60 mm petri dish with a 25 mm glass dish glued in the central area. TCE or PER was added to the central glass dish so that it would evaporate and dissolve in the surrounding medium in which cells were growing. The results showed that the concentration of TCE or PER in medium increased significantly within 20 min and then decreased very rapidly with time. After a 24 h incubation, the residual of TCE or PER in the medium was very low, but was displayed in a dose-dependent manner. Treatment of cells with either TCE or PER resulted in a dose- and time-dependent inhibition of cell growth. A significantly increase in the frequency of micronuclei (MN) was also observed with either TCE or PER treatment. Low doses of TCE (5-20 microl) or PER (1-5 microl) significantly enhanced the intracellular glutathione (GSH) level. However, the level of GSH rapidly decreased with higher doses of TCE (40-80 microl) or PER (10-20 microl). Depletion of cellular GSH showed no effect on the sensitivity of cells to TCE or PER treatment. GSH-conjugation has been proposed as an activation mechanism to account for the nephrotoxicity of TCE and PER, however the toxicity of TCE and PER to CHO-K1 cells is probably mediated through a distinct mechanism.


Assuntos
Divisão Celular/efeitos dos fármacos , Tetracloroetileno/toxicidade , Tricloroetileno/toxicidade , Animais , Células CHO , Cricetinae , Meios de Cultura/química , Glutationa/metabolismo , Humanos , Micronúcleos com Defeito Cromossômico/efeitos dos fármacos , Testes para Micronúcleos , Solventes/toxicidade , Tetracloroetileno/farmacologia , Tricloroetileno/farmacologia , Volatilização
14.
Am J Respir Cell Mol Biol ; 25(1): 3-7, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11472967

RESUMO

Tumor necrosis factor-alpha receptor knockout (TNF-alphaRKO) mice have homozygous deletions of the genes that code for both the 55- and 75-kD receptors. The mice are protected from the fibrogenic effects of bleomycin, silica, and inhaled asbestos. The asbestos-exposed animals exhibit reduced expression of other peptide growth factors such as transforming growth factor (TGF)-alpha, platelet-derived growth factors, and TGF-beta. In normal animals, these and other cytokines are elaborated at high levels during the development of fibroproliferative lung disease, but there is little information available that has allowed investigators to establish the role of the individual growth factors in disease pathogenesis. Here, we show that overexpression of TGF-beta(1) by means of a replication-deficient adenovirus vector induces fibrogenesis in the lungs of the fibrogenic-resistant TNF-alphaRKO mice. The fibrogenic lesions developed in both the KO and background controls within 7 d, and both types of animals exhibited similar incorporation of bromodeoxyuridine. Interestingly, airway epithelial cell proliferation appeared to be suppressed, perhaps due to the presence of the TGF-beta(1), a well-known inhibitor of epithelial mitogenesis. Before these experiments, there was no information available that would provide a basis for predicting whether or not TGF-beta(1) expression induces fibroproliferative lung disease in fibrogenic-resistant TNF-alphaRKO mice, an increasingly popular animal model.


Assuntos
Fibrose Pulmonar/genética , Receptores do Fator de Necrose Tumoral/fisiologia , Fator de Crescimento Transformador beta/metabolismo , Adenoviridae/genética , Animais , Bromodesoxiuridina , Vetores Genéticos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores do Fator de Necrose Tumoral/genética , Transdução Genética , Fator de Crescimento Transformador beta/genética
15.
Int J Radiat Oncol Biol Phys ; 50(3): 717-26, 2001 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-11395240

RESUMO

PURPOSE: Concomitant chemotherapy and radiotherapy (CCRT), followed by adjuvant chemotherapy, has improved the outcome of nasopharyngeal carcinoma (NPC). However, the prognosis and patterns of failure after this combined-modality treatment are not yet clear. In this report, the prognostic factors and failure patterns we observed with CCRT may shed new light in the design of future trials. METHODS AND PATIENTS: One hundred forty-nine (149) patients with newly diagnosed and histologically proven NPC were prospectively treated with CCRT followed by adjuvant chemotherapy between April 1990 and December 1997. One hundred and thirty-three (89.3%) patients had MRI of head and neck for primary evaluation before treatment. Radiotherapy was delivered either at 2 Gy per fraction per day up to 70 Gy or 1.2 Gy per fraction, 2 fractions per day, up to 74.4 Gy. Chemotherapy consisted of cisplatin and 5-fluorouracil. According to the AJCC 1997 staging system, 32 patients were in Stage II, 53 in Stage III, and 64 in Stage IV (M0). RESULTS: Univariate analysis revealed that WHO (World Health Organization) Type II histology, T4 classification, and parapharyngeal extension were poor prognostic factors for locoregional control. Multivariate analysis revealed that T4 disease was the most important adverse factor that affects locoregional control, the risk ratio being 5.965 (p = 0.02). Univariate analysis for distant metastasis revealed that T4 and N3 classifications, serum LDH level > 410 U/L (normal range, 180-460), parapharyngeal extension, and infiltration of the clivus were significantly associated with poor prognosis. Multivariate analysis, however, revealed that T4 classification and N3 category were the only two factors that predicted distant metastasis; the risk ratios were 3.994 (p = 0.02) and 3.390 (p = 0.01), respectively. Therefore, based on the risk factor analysis, we were able to identify low-, intermediate-, and high-risk patients. Low-risk patients were those without the risk factors mentioned above. They consisted of Stage II patients with T2aN0, T1N1, and T2aN1 categories and of Stage III patients with T1N2 and T2aN2 categories. Their risk of recurrence is low (4%). Intermediate-risk patients were those with at least one univariate risk factor. They are Stage II patients with T2bN0 and T2bN1 categories and Stage III patients with T2bN2 and T3N0-2 categories. The risk of recurrence is modest (18%). High-risk patients have risk factors by multivariate analysis. They are stage T4 or N3 patients. Their risk of recurrence is high (36%). CONCLUSION: Low-risk patients have an excellent outcome. Future trials should focus on reducing treatment-associated toxicities and complications and reevaluate the benefit of sequential adjuvant chemotherapy. The recurrence in treatment of intermediate-risk patients is modest; CCRT and adjuvant chemotherapy may be the best standard for them. Patients with T4 and N3 disease have poorer prognosis. Hyperfractionated radiotherapy may be considered for the T4 patients. Future study in these high-risk patients should also address the problem of distant spread of the disease.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Nasofaríngeas/tratamento farmacológico , Neoplasias Nasofaríngeas/radioterapia , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Quimioterapia Adjuvante , Cisplatino/administração & dosagem , Cisplatino/efeitos adversos , Intervalo Livre de Doença , Fracionamento da Dose de Radiação , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/efeitos adversos , Previsões , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Nasofaríngeas/patologia , Metástase Neoplásica , Estadiamento de Neoplasias , Modelos de Riscos Proporcionais , Estudos Prospectivos , Radioterapia/efeitos adversos , Fatores de Risco , Resultado do Tratamento
16.
Proc Natl Acad Sci U S A ; 98(10): 5898-903, 2001 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-11331772

RESUMO

Members of the fibroblast growth factor (FGF) family play a critical role in embryonic lung development and adult lung physiology. The in vivo investigation of the role FGFs play in the adult lung has been hampered because the constitutive pulmonary expression of these factors often has deleterious effects and frequently results in neonatal lethality. To circumvent these shortcomings, we expressed FGF-3 in the lungs under the control of the progesterone antagonist-responsive binary transgenic system. Four binary transgenic lines were obtained that showed ligand-dependent induction of FGF-3 with induced levels of FGF-3 expression dependent on the levels of expression of the GLp65 regulator as well as the dose of the progesterone antagonist, RU486, administered. FGF-3 expression in the adult mouse lung resulted in two phenotypes depending on the levels of induction of FGF-3. Low levels of FGF-3 expression resulted in massive free alveolar macrophage infiltration. High levels of FGF-3 expression resulted in diffuse alveolar type II cell hyperplasia. Both phenotypes were reversible after the withdrawal of RU486. This system will be a valuable means of investigating the diverse roles of FGFs in the adult lung.


Assuntos
Fatores de Crescimento de Fibroblastos/metabolismo , Pulmão/efeitos dos fármacos , Proteínas Proto-Oncogênicas/metabolismo , Animais , Fator 3 de Crescimento de Fibroblastos , Fatores de Crescimento de Fibroblastos/genética , Ligantes , Pulmão/metabolismo , Camundongos , Camundongos Transgênicos , Mifepristona/farmacologia , Fenótipo , Proteínas Proto-Oncogênicas/genética
17.
J Affect Disord ; 64(2-3): 185-93, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11313085

RESUMO

BACKGROUND: Circulating soluble interleukin-2 receptors (sIL-2Rs) and soluble interleukin-6 receptors (sIL-6Rs) are stable immune measures. Elevated plasma sIL-2R levels are present in patients with schizophrenia, major depression, and bipolar mania, but not with minor psychiatric disorders. The increased plasma sIL-2R levels are state-dependent in bipolar mania. However, altered production of plasma sIL-6R and the effects of clinical characteristics on plasma sIL-6R and sIL-2R levels in bipolar disorder remains uncertain. METHODS: Plasma sIL-2R and sIL-6R levels were measured in 31 Taiwanese bipolar manic (DSM-IV) patients with Young Mania Rating Scale (YMRS) scores of > or =26 as well as during the subsequent remission (YMRS< or =12), and equal numbers of age- and gender-matched healthy controls. The relationships of clinical variables such as age, age of onset, smoking, medication status, coexisting psychotic features, number of prior episodes, duration of illness, presence of depression before or following the manic episode, and manic severity to plasma sIL-2R and sIL-6R levels in acute mania along with remission were examined. RESULTS: Plasma sIL-2R but not sIL-6R levels were significantly higher in acute mania than in subsequent remission (P<0.05) and controls (P<0.0005). In acute mania, the plasma sIL-2R levels were significantly correlated to YMRS scores (r=0.34, P<0.05). The remaining clinical variables had no effect on plasma sIL-2R and sIL-6R levels in acute mania or remission. There was a significantly positive relationship between the reduction of plasma sIL-2R levels from the acute to follow-up measurements (DeltasIL-2R) and symptomatic improvement of acute mania (DeltaYMRS) (r=0.61, P<0.001). LIMITATIONS: Our sample included medicated and unmedicated patients in acute mania. The psychotropic medication may have divergent effects on the plasma sIL-2R levels in acute mania and subsequent remission. CONCLUSIONS: Elevation of plasma sIL-2R but not sIL-6R levels in bipolar mania supports the idea that the immunomodulatory mechanism may vary in different psychotic disorders. In contrast to being a trait marker in schizophrenia and depressive disorder, plasma sIL-2R levels may be considered a biological indicator of manic severity in a group of bipolar affective patients.


Assuntos
Transtorno Bipolar/sangue , Transtorno Bipolar/diagnóstico , Receptores de Interleucina-2/sangue , Doença Aguda , Adulto , Biomarcadores/sangue , Ritmo Circadiano/fisiologia , Feminino , Seguimentos , Humanos , Masculino , Escalas de Graduação Psiquiátrica , Receptores de Interleucina-6/sangue , Indução de Remissão , Índice de Gravidade de Doença , Solubilidade , Inquéritos e Questionários
18.
Cell Tissue Res ; 303(3): 423-31, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11320658

RESUMO

The role of the pineal gland in regulating immune function has been extensively investigated. However, there is little information about possible feedback mechanisms of immunological factors on pineal gland neuroendocrine functions. Therefore, experiments were designed to test the effects of cytokines (interferon-gamma, IFN-gamma, interleukin-1 beta, IL-1 beta; tumor necrosis factor-alpha, TNF-alpha; transforming growth factor-beta 1, TGF-beta 1) on pinealocytes and the role of pineal microglia in mediating these cytokine effects in the pineal gland of the rat. Our studies showed that IFN-gamma enhanced 5-hydroxytryptamine (5-HT) content (measured by high-performance liquid chromatography, HPLC) and increased pinealocyte process length in pineal cultures. IL-1 beta treatment decreased 5-HT content in both cell and organ culture, but exhibited no effect on pinealocyte process length. 5-HT content and process length were decreased by TNF-alpha treatment. IFN-gamma and IL-1 beta exhibited no significant effect in the absence of microglia in cell cultures. In contrast, TNF-alpha caused a further decline in 5-HT content even in the absence of microglia in the cultures. The effects of TNF-alpha were probably due to toxic effects, since an increased number of pyknotic nuclei were observed in treated cultured explants. TGF-beta 1 treatment caused aggregation of pinealocytes in cultures and suppressed process length and 5-HT content. In conclusion, cytokine effects on pinealocytes may be mediated by microglia (IFN-gamma and IL-1 beta) or act directly on pinealocytes (TNF-alpha). The presence of IL-1 beta and TGF-beta 1 protein in the pineal gland and the suppressive effect of TGF-beta 1 on pinealocytes in cultures further suggest that endogenous cytokines play regulatory roles in response to peripheral homeostatic changes.


Assuntos
Citocinas/farmacologia , Microglia/fisiologia , Glândula Pineal/efeitos dos fármacos , Fator de Crescimento Transformador beta/farmacologia , Animais , Animais Recém-Nascidos , Células Cultivadas , Cromatografia Líquida de Alta Pressão , Relação Dose-Resposta a Droga , Feminino , Processamento de Imagem Assistida por Computador , Imuno-Histoquímica , Interferon gama/farmacologia , Interleucina-1/farmacologia , Masculino , Microscopia Eletrônica de Varredura , Glândula Pineal/fisiologia , Ratos , Ratos Sprague-Dawley , Serotonina/análise , Fator de Crescimento Transformador beta1 , Fator de Necrose Tumoral alfa/farmacologia
19.
Exp Lung Res ; 27(8): 639-53, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11768716

RESUMO

Lung fibroblasts are activated to proliferate and produce connective tissue during the development of lung fibrosis. The 129 mouse strain does not develop asbestos-induced fibrogenesis, whereas several other inbred strains rapidly respond to inhaled fibers. Thus, in the experiments presented here, we have compared the responses of primary lung fibroblasts isolated from 129 and C57BL/6 mice. The 129 and C57BL/6 mouse lung fibroblasts (MLFs) proliferated similarly in 10% fetal bovine serum (FBS), but after quiescence, the 129 MLFs grew more slowly in serum and responded less to the BB isoform of platelet-derived growth factor. This is consistent with our finding that the mRNA for the PDGF-a receptor exhibits reduced expression by the 129 MLFs compared to those from C57BL/6 mice. Fibroblasts from the SJL mouse strain, from a C57BL/6-129 hybrid, and from the 3T3 cell line all proliferated more vigorously than MLFs from the 129 mice. In addition, the 129 MLFs exhibited reduced expression of alpha1 procollagen mRNA consequent to treatment with tumor necrosisfactor alpha. Based on these new findings, we suggest that the reduced fibrogenesis in asbestos-exposed 129 mice is due to an intrinsic difference in the ability of the lung fibroblasts to respond to peptide growth factors.


Assuntos
Pulmão/efeitos dos fármacos , Fator de Crescimento Derivado de Plaquetas/farmacologia , Células 3T3 , Animais , Biomarcadores/análise , Northern Blotting , Contagem de Células , Divisão Celular/efeitos dos fármacos , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Relação Dose-Resposta a Droga , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Imuno-Histoquímica , Pulmão/citologia , Camundongos , Camundongos Endogâmicos C57BL , Fator de Crescimento Derivado de Plaquetas/genética , RNA Mensageiro/metabolismo , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/biossíntese , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/genética , Especificidade da Espécie , Fator de Necrose Tumoral alfa/farmacologia , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/genética
20.
Int J Radiat Oncol Biol Phys ; 48(5): 1323-30, 2000 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-11121629

RESUMO

PURPOSE: The purpose of this study is to demonstrate long-term survival of nasopharyngeal carcinoma treated with concomitant chemotherapy and radiotherapy (CCRT) followed by adjuvant chemotherapy. METHODS AND PATIENTS: One hundred and seven patients with Stage III and IV (American Joint Committee on Cancer, AJCC, 1988) nasopharyngeal carcinoma (NPC) were treated with concomitant chemotherapy and radiotherapy (CCRT) followed by adjuvant chemotherapy between April 1990 and December 1997 in Koo Foundation Sun Yat-Sen Cancer Center, Taipei. The dose of radiation was 70 Gray (Gy) given in 35 fractions, 5 fractions per week. Two courses of chemotherapy, consisting of cisplatin and 5-fluorouracil, were delivered simultaneously with radiotherapy in Weeks 1 and 6 and two additional monthly courses were given after radiotherapy. According to the AJCC 1997 staging system, 32 patients had Stage II disease, 44 had Stage III, and 31 had Stage IV disease. RESULTS: With median follow-up of 44 months, the 5-year overall survival rate in all 107 patients was 84.1%, disease-free survival rate was 74.4%, and locoregional control rate was 89.8%. The 3-year overall survival for Stage II was 100%, for Stage III it was 92.8%, and for Stage IV, 69. 4% (p = 0.0002). The 3-year disease-free survival for Stage II was 96.9%, for Stage III it was 87.7%, and for Stage IV it was 51.9% (p = 0.0001). CONCLUSION: CCRT and adjuvant chemotherapy is effective in Taiwanese patients with advanced NPC. The prognosis of AJCC 1997 Stage II and III disease is excellent, but, for Stage IV (M0), it is relatively poor. Future strategies of therapy should focus on high-risk AJCC 1997 Stage IV (M0) cohort.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma/tratamento farmacológico , Carcinoma/radioterapia , Neoplasias Nasofaríngeas/tratamento farmacológico , Neoplasias Nasofaríngeas/radioterapia , Radiossensibilizantes/uso terapêutico , Adulto , Idoso , Carcinoma/mortalidade , Quimioterapia Adjuvante , Cisplatino/administração & dosagem , Terapia Combinada , Feminino , Fluoruracila/administração & dosagem , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Nasofaríngeas/mortalidade , Estadiamento de Neoplasias , Cooperação do Paciente , Dosagem Radioterapêutica , Taxa de Sobrevida , Taiwan , Falha de Tratamento
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