Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 8 de 8
Filtrar
Más filtros










Base de datos
Intervalo de año de publicación
1.
J Pharm Sci Pharmacol ; 1(2): 87-100, 2014 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-25664332

RESUMEN

Ewing Sarcoma (ES) is a rare form of bone cancer that most commonly affects children and adolescents. Chromosomal translocations are fundamental to the development of Ewing Sarcoma, linked to the changes in gene expression affecting transcription factors. Histone acetyl transferases (HATs) and histone deacetylases (HDACs) regulate transcription by modifying acetylation of both histones and transcription factors. Despite the use of multimodal therapeutic approaches current therapies are associated with significant short and long-term side effects. Hence, new therapeutic approaches are needed. In this study, we show that ERG/EWS-ERG, inhibits transcriptional activation properties of RXRα. These results suggest that ERG/EWS-ERG/EWS-Fli-1 may target transcriptional co-activators and transcriptional repressors and thereby regulate RXRα transcriptional activity. To understand the molecular mechanism of action, how the fusion protein targets nuclear receptor function, and to provide a clue for the cancer health disparity seen in Ewing Sarcoma, we hypothesized that the aberrant fusion protein, EWS-ERG/EWS-Fli-1 regulates HDACs-mediated repressor complex and inhibits the binding of transcriptional activator complex causing transcriptional repression of RXRα activity. Since it is known that HDACs regulate nuclear receptors, we proposed that HDAC inhibitor, valproic acid (VPA), an anti-epileptic drug, may reverse the inhibitory properties of EWS-ERG/EWS-Fli-1 oncoprotein on RXRα transcriptional activity and might therefore be used as therapeutic agent in ES. We demonstrate that VPA reverses the inhibitory effect of EWSERG/EWS-Fli-1 on RXRα transcriptional activity and also inhibits the cell growth. Furthermore, VPA induces apoptosis and restored the expression of RXRα target genes RARß, CRABPII and p21 activity and repressed the expression of aberrant fusion proteins, EWS-ERG and EWS-Fli-1 in Ewing Sarcoma cells. Thus, therapeutic regulation of transcriptional repressor properties of EWS-ERG/EWS-Fli-1 with an anti-epileptic drug with a promising new potential might have a profound impact on prevention, management and treatment of Ewing Sarcoma. Therapeutic use of VPA in minority patients may help reduce the health disparity.

2.
Int J Oncol ; 39(1): 111-9, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21519790

RESUMEN

An ETS family member, ETS Related Gene (ERG) is involved in the Ewing family of tumors as well as leukemias. Rearrangement of the ERG gene with the TMPRSS2 gene has been identified in the majority of prostate cancer patients. Additionally, overexpression of ERG is associated with unfavorable prognosis in prostate cancer patients similar to leukemia patients. Histone acetyltransferases (HATs) and histone deacetylases (HDACs) regulate transcription as well as epigenetic status of genes through acetylation of both histones and transcription factors. Deregulation of HATs and HDACs is frequently seen in various cancers, including prostate cancer. Many cellular oncogenes as well as tumor viral proteins are known to target either or both HATs and HDACs. Several studies have demonstrated that there are alterations of HDAC activity in prostate cancer cells. Recently, we found that ERG binds and inhibits HATs, which suggests that ERG is involved in deregulation of protein acetylation. Additionally, it has been shown that ERG is associated with a higher expression of HDACs. In this study, we tested the effect of the HDAC inhibitors valproic acid (VPA) and trichostatin-A (TSA) on ERG-positive prostate cancer cells (VCaP). We found that VPA and TSA induce apoptosis, upregulate p21/Waf1/CIP1, repress TMPRSS2-ERG expression and affect acetylation status of p53 in VCaP cells. These results suggest that HDAC inhibitors might restore HAT activity through two different ways: by inhibiting HDAC activity and by repressing HAT targeting oncoproteins such as ERG.


Asunto(s)
Apoptosis/efectos de los fármacos , Inhibidores de Histona Desacetilasas/farmacología , Ácidos Hidroxámicos/farmacología , Neoplasias de la Próstata/fisiopatología , Proteínas Proto-Oncogénicas c-ets/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Ácido Valproico/farmacología , Acetilación/efectos de los fármacos , Animales , Células COS , Caspasa 3/metabolismo , Caspasa 7/metabolismo , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Chlorocebus aethiops , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Histona Desacetilasas/metabolismo , Humanos , Masculino , Modelos Biológicos , Neoplasias de la Próstata/genética , Proteínas Proto-Oncogénicas c-ets/genética , Quinasas p21 Activadas/genética , Quinasas p21 Activadas/metabolismo
3.
Yakugaku Zasshi ; 130(3): 441-6, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20190529

RESUMEN

The graduate students in our laboratory underwent 4-5 months of training at Maizuru Kyosai Hospital. To evaluate the effectiveness of this long-term practical training course of the off-campus hospital, we conducted a questionnaire survey before and after the course among the students and the pharmacists. The results of the survey suggest that the students gained experience regarding pharmaceutical management and came to understand the importance of pharmaceutical care during the course. They had an opportunity to connect clinical practice with the research activities conducted at the university. With regard to the pharmacists, this course has motivated them to act as mentors during the practical training, and therefore was also of significance to them. However, this long-term practical training at the off-campus hospital necessitated a change in lifestyle and living arrangements for the students, which placed stress on them. They required emotional support from university staff before and during the placement. These results show that in order to maintain close collaboration with the hospital and to ensure the success of long-term practical training at an off-campus hospital, academic and emotional support for the students is necessary.


Asunto(s)
Educación de Postgrado en Farmacia , Farmacéuticos/psicología , Servicio de Farmacia en Hospital , Estudiantes de Farmacia/psicología , Estrés Psicológico , Encuestas y Cuestionarios
4.
J Cell Physiol ; 219(3): 634-41, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19170108

RESUMEN

BRCA1 is a tumor suppressor gene that is mutated in families with breast and ovarian cancer. Several BRCA1 splice variants are found in different tissues, but their subcellular localization and functions are poorly understood at the moment. We previously described BRCA1 splice variant BRCA1a to induce apoptosis and function as a tumor suppressor of triple negative breast, ovarian and prostate cancers. In this study we have analyzed the function of BRCA1 isoforms (BRCA1a and BRCA1b) and compared them to the wild-type BRCA1 protein using several criteria like studying expression in normal and tumor cells by RNase protection assays, subcellular localization/fractionation by immunofluorescence microscopy and Western blot analysis, transcription regulation of biological relevant proteins and growth suppression in breast cancer cells. We are demonstrating for the first time that ectopically expressed GFP-tagged BRCA1, BRCA1a, and BRCA1b proteins are localized to the mitochondria, repress ELK-1 transcriptional activity and possess antiproliferative activity on breast cancer cells. These results suggest that the exon 9, 10, and 11 sequences (aa 263-1365) which contain two nuclear localization signals, p53, Rb, c-Myc, gamma-tubulin, Stat, Rad51, Rad50 binding domains, angiopoietin-1 repression domain are not absolutely required for mitochondrial localization and growth suppressor function of these proteins. Since mitochondrial dysfunction is a hallmark of cancer, we can speculate that the mitochondrial localization of BRCA1 proteins may be functionally significant in regulating both the mitochondrial DNA damage as well as apoptotic activity of BRCA1 proteins and mislocalization causes cancer. J. Cell. Physiol. 219: 634-641, 2009. (c) 2009 Wiley-Liss, Inc.


Asunto(s)
Proteína BRCA1/metabolismo , Mitocondrias/metabolismo , Proteína Elk-1 con Dominio ets/metabolismo , Empalme Alternativo , Apoptosis , Proteína BRCA1/genética , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Línea Celular Tumoral , Proliferación Celular , Daño del ADN , Femenino , Genes BRCA1 , Inhibidores de Crecimiento/genética , Inhibidores de Crecimiento/metabolismo , Células HL-60 , Células HeLa , Humanos , Células K562 , Masculino , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Activación Transcripcional , Proteína Elk-1 con Dominio ets/genética
5.
J Diet Suppl ; 5(4): 401-10, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-22436099

RESUMEN

The effects of turmeric extracts on the pharmacokinetics of nifedipine were examined in 10 healthy volunteers. An open-label and randomized crossover study was performed at 2-week intervals. In the control experiment, after a 10 h overnight fast, 10 mg of nifedipine (Adalat® capsule) was administered orally and blood was collected at 0, 0.5, 1, 2, 3, 4, 5, 6, and 8 h. In the combination experiment, the volunteers were orally administered 10 mg of nifedipine together with six tablets containing concentrated turmeric extract (480 mg of curcuminoid per six tablets), which is the general daily dose, and blood was sampled as above. The time profile of the plasma concentration of nifedipine in the control was comparable to that in combination with turmeric extract, as were the pharmacokinetic parameters: that is, the mean ratio of turmeric extract/control group (90% confidence interval: CI); C(max), 0.98 (0.95, 1.01) and AUC(0 - ∞) 1.00 (0.98, 1.02). In addition, the volunteers all completed the study without any serious adverse events. Consumption of the turmeric extract did not affect the pharmacokinetics of nifedipine after a single oral administration.


Asunto(s)
Curcuma/química , Interacciones de Hierba-Droga , Nifedipino/farmacocinética , Extractos Vegetales/farmacología , Administración Oral , Adulto , Área Bajo la Curva , Estudios Cruzados , Femenino , Humanos , Masculino , Persona de Mediana Edad , Nifedipino/sangre , Fitoterapia , Extractos Vegetales/administración & dosificación , Valores de Referencia , Adulto Joven
6.
Oncogene ; 23(42): 7087-94, 2004 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-15273724

RESUMEN

In the majority of Ewing's family tumors, chromosomal translocation t(11;22) leads to aberrant fusion of RNA-binding protein EWS with DNA-binding ETS transcriptional factor Fli-1. EWS-Fli-1 has altered the transcriptional activity and modulating its downstream target genes through this transcriptional activity is thought to be responsible for this tumor. We have previously shown that both EWS-Fli-1 and Fli-1 have antiapoptotic activity against several apoptotic inducers. Here, we show that the transcriptional activity of EWS-Fli-1 and Fli-1 is not essential for its antiapoptotic activity. We also demonstrate that EWS-Fli-1 and Fli-1 interact with CBP through its amino-terminal region and inhibit the CBP-dependent transcriptional activity of RXR. This activity appears to be independent of DNA-binding activity of EWS-Fli-1. Introduction of the dominant-negative form of CBP into Ewing's sarcoma cells sensitizes these cells against genotoxic or retinoic-acid induced apoptosis. These results suggest that the ability of EWS-Fli-1/Fli-1 to target transcriptional cofactor(s) and modulate apoptotic pathways may be responsible for its antiapoptotic and tumorigenic activities.


Asunto(s)
Apoptosis/fisiología , Neoplasias Óseas/genética , Supervivencia Celular/fisiología , Gelsolina/farmacología , Sarcoma de Ewing/genética , Actinas/genética , Secuencia de Bases , Cromosomas Humanos Par 11/genética , Cromosomas Humanos Par 22/genética , Cartilla de ADN , Gelsolina/genética , Humanos , Proteínas de Microfilamentos , Reacción en Cadena de la Polimerasa/métodos , Receptores Citoplasmáticos y Nucleares/genética , Transactivadores , Transcripción Genética , Transfección , Translocación Genética
7.
Drug Metab Pharmacokinet ; 17(4): 363-6, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-15618687

RESUMEN

The effect of calcium polycarbophil on the absorption of cefdinir, cephalosporin derivative, was evaluated in both in vitro and in vivo studies. In the in vitro study, the release of cefdinir from a cellulose membrane in the presence or absence of metal cations was measured using the dissolution test procedure. In the in vivo study, volunteers and a randomized crossover design with two phases were used. In the first phase, the volunteers received 200 mg of cefdinir alone (Study 1); in the other phase, they received 200 mg of cefdinir and 1200 mg of fine calcium polycarbophil granules concomitantly (Study 2). The cefdinir concentrations in the samples or serum were measured by an UV-VIS spectrophotometer or high-performance liquid chromatography. Release in the presence of iron ions was slower than that in the absence of metal ions, however no difference was observed between release in the presence of calcium ions and that in the absence of metal ions. No difference was observed in AUC(0-10), C(max) and t(max) between Study 1 and Study 2. The absorption of cefdinir was not affected by co-administration of calcium polycarbophil. Moreover, the in vitro study on the release of drugs from a cellulose membrane may predict the absorption of a drug caused by the formation of chelate complexes between the drug and metal ions.

8.
Dev Growth Differ ; 33(6): 639-649, 1991 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37281806

RESUMEN

We isolated a mouse monoclonal antibody (FAD-II) that disrupts cell-substratum adhesion of amphibian (Xenopus laevis) epithelial cells and endothelial cells. The effect of the antibody was cell-type specific, and the antibody had no effect on fibroblastic cells while fibronectin peptide blocked cell-substratum adhesion of all the cell types examined. In developing frog embryos, the epitopes recognized by the antibody were detected in pronephrotic ducts and in other tissue cells of embryos (from stage 33/34 afterwards). In adult tissues, the antibody mainly recognized antigens in extracelluar matrices. The antigens recognized by the antibody seems to be novel glycoepitopes in frog cells.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA