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1.
Plant Cell Environ ; 47(5): 1877-1894, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38343027

RESUMEN

ETHYLENE RESPONSE FACTOR 1 (ERF1) plays an important role in integrating hormone crosstalk and stress responses. Previous studies have shown that ERF1 is unstable in the dark and its degradation is mediated by UBIQUITIN-CONJUGATING ENZYME 18. However, whether there are other enzymes regulating ERF1's stability remains unclear. Here, we use various in vitro and in vivo biochemical, genetic and stress-tolerance tests to demonstrate that both CONSTITUTIVE PHOTOMORPHOGENIC 1 (COP1) and SUMO-CONJUGATING ENZYME 1 (SCE1) regulate the stability of ERF1. We also performed transcriptomic analyses to understand their common regulatory pathways. We show that COP1 mediates ERF1 ubiquitination in the dark while SCE1 mediates ERF1 sumoylation in the light. ERF1 stability is positively regulated by SCE1 and negatively regulated by COP1. Upon abiotic stress, SCE1 plays a positive role in stress defence by regulating the expression of ERF1's downstream stress-responsive genes, whereas COP1 plays a negative role in stress response. Moreover, ERF1 also promotes photomorphogenesis and the expression of light-responsive genes. Our study reveals the molecular mechanism of how COP1 and SCE1 counteract to regulate ERF1's stability and light-stress signalling crosstalk.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Etilenos/metabolismo , Regulación de la Expresión Génica de las Plantas , Fotoperiodo , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo
2.
Psychol Med ; 53(3): 722-730, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-34011426

RESUMEN

BACKGROUND: The retention of patients under methadone maintenance treatment (MMT) is an indication for the effectiveness of the therapy. We aimed to explore the relation between mortality and the cumulative MMT duration. METHODS: A retrospective cohort analysis was performed using Taiwan Illicit Drug Issue Database (TIDID) and National Health Insurance Research Database (NHIRD) during 2012-2016. We included 9149 and 11 112 MMT patients as the short and long groups according to the length of their cumulative MMT duration, 1-364 and ⩾365 days, respectively. The risk of mortality was calculated by Cox proportional hazards regression model with time-dependent exposure to MMT, and the survival probability was plotted with the Kaplan-Meier curve. RESULTS: The mortality rates were 2.51 and 1.51 per 100 person-years in the short and long cumulative MMT duration groups, respectively. After adjusting for on or off MMT, age, sex, marital status, education level, maximum methadone dose, and comorbidities (human immunodeficiency virus, depression, hepatitis C virus, hepatitis B virus, alcoholic liver disease, and cardiovascular disease), the long group had a lower risk of death (hazard ratio = 0.67; 95% confidence interval 0.60-0.75) than the short group. Increased risk was observed in patients with advanced age, being male, unmarried, infected by HIV, HCV, and HBV, and diagnosed with depression, ALD, and CVD. Causes of death were frequently related to drug and injury. CONCLUSIONS: Longer cumulative MMT duration is associated with lower all-cause and drug-related mortality rate.


Asunto(s)
Hepatitis C , Tratamiento de Sustitución de Opiáceos , Humanos , Masculino , Femenino , Estudios Retrospectivos , Metadona/uso terapéutico , Estudios de Cohortes , Hepatitis C/tratamiento farmacológico , Hepatitis C/epidemiología
3.
Animals (Basel) ; 12(24)2022 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-36552503

RESUMEN

Hematological and plasma biochemical examination are crucial in the veterinary care of sugar gliders, which are increasingly popular in Taiwan and the United States. However, published research of the species' reference interval and related influencing factors were rare. The objectives of this study were to establish the hematological and plasma biochemical reference values for captive sugar gliders in Taiwan and to evaluate the influence of factors including age, gender, neuter status, location, season, diet, caging arrangement, and other pets in the household. A total of 42 clinically healthy pet sugar gliders were recruited. Morphometrical measurements and physiological data were collected, and hematological and plasma biochemical examinations were performed. The reference value of each index was calculated using Reference Value Advisor (RVA) software, following the American Society for Veterinary Clinical Pathology (ASVCP) guidelines. Normality of data distribution was tested, and data transformation was conducted. The parametric method and robust method were used to determine reference limits. Univariate analysis was performed, and multiple regression models were built for each hematological and plasma biochemical parameter. Red blood cell, hematocrit, and hemoglobin levels were higher in males, compared to females, while they were lower in the neutered group, compared to the intact group. Relative neutrophil counts were higher in elder sugar gliders, while relative lymphocyte counts were lower. Aspartate transaminase levels were higher in elder sugar gliders, while albumin levels were lower. Blood urea nitrogen levels were highest in spring. The blood profile and related effects presented in this study can provide useful information for veterinary care in pet sugar gliders.

5.
Adv Ther ; 38(6): 2908-2919, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33559050

RESUMEN

INTRODUCTION: The health benefits of entering methadone maintenance treatment (MMT) for opioid-dependent persons may not be merely limited to therapy of opioid use disorder. We aimed to compare the healthcare utilization of MMT patients before and after MMT. METHODS: A retrospective analysis was performed using the Taiwan Illicit Drug Issue Database and the National Health Insurance Research Database (NHIRD) between 2014 and 2016. We included 1255 newly enrolled MMT patients in 2015 and randomly selected 5020 patients from NHIRD matched by age and gender as the comparison group. Changes in healthcare utilization 1 year before and 1 year after the date of the index date (MMT initiation) were compared within and between MMT and comparison groups. RESULTS: During the 1-year period following MMT, the hospitalization length was considerably decreased, while the number of outpatient visits, emergency department (ED) visits, and ED expenditure significantly increased in MMT patients. Multivariable linear regression with the difference-in-difference approach revealed that all the categories of healthcare utilization increased, except for a minor increase of outpatient expenditure and a slight decrease of hospitalization length for the MMT group relative to the comparison group. Increases in utilization of the departments of psychiatry and infectious diseases of the MMT patients were considerable. CONCLUSION: MMT is associated with increased healthcare utilization, and departments of psychiatry and infectious diseases play substantial roles. Policy-makers should warrant access for all who need healthcare by ensuring the availability of the treatment for drug dependence.


Asunto(s)
Metadona , Trastornos Relacionados con Opioides , Atención a la Salud , Humanos , Metadona/uso terapéutico , Tratamiento de Sustitución de Opiáceos , Trastornos Relacionados con Opioides/tratamiento farmacológico , Trastornos Relacionados con Opioides/epidemiología , Estudios Retrospectivos , Taiwán
6.
Cell Death Discov ; 7(1): 8, 2021 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-33436575

RESUMEN

Glioblastoma (GBM) is the most aggressive brain tumor and relapses after chemo- or radiotherapy in a short time. The anticancer drug temozolamide (TMZ) is commonly used for GBM treatment, but glioma stem-like cells (GSCs) often lead to drug resistance and therapeutic failure. To date, the mechanism of GSC formation in TMZ-treated GBM remains largely unknown. CCAAT/Enhancer-binding protein delta (CEBPD) is an inflammation-responsive transcription factor and is proposed to be oncogenic in the context of drug resistance, prompting us to clarify its role in TMZ-resistant GBM. In this study, we first found that the CEBPD protein levels in GBM patients were significantly increased and further contributed to TMZ resistance by promoting GSC formation. Accordingly, the protein levels of stemness transcription factors, namely, SRY-box transcription factor 2 (SOX2), octamer-binding transcription factor 4 (OCT4), NANOG, and ATP-binding cassette subfamily A member 1 (ABCA1), were increased in GSCs and TMZ-treated GBM cells. Increased binding of CEBPD to promoter regions was observed in GSCs, indicating the direct regulation of these GSC-related genes by CEBPD. In addition, an ABCA1 inhibitor increased the caspase 3/7 activity of TMZ-treated GSCs, suggesting that TMZ efflux is controlled by ABCA1 activity and that the expression levels of the ABCA1 gene are an indicator of the efficiency of TMZ treatment. Together, we revealed the mechanism of CEBPD-mediated GSC drug resistance and proposed ABCA1 inhibition as a potential strategy for the treatment of TMZ-resistant GBM.

7.
J Chin Med Assoc ; 83(12): 1093-1101, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32732531

RESUMEN

BACKGROUND: Animal models of trauma have shown that females have better posttraumatic survival; however, results of previous studies on the influence of gender on major trauma patients have been controversial. This study aimed to evaluate the association between gender and survival in major trauma patients. METHODS: We retrospectively analyzed patients registered in Taiwan's National Health Insurance Research Database between 2008 and 2012 with the diagnosis codes 800-939 and 950-957 (International Classification of Diseases, ninth revision, clinical modification). Data on gender, age, catastrophic illness, and new injury severity score (NISS) ≥16 were collected for comparing patients' mortality after trauma. Propensity score matching (PSM) was performed to eliminate dissimilarities in age, comorbidities, NISS, and primary traumatic regions between the genders. RESULTS: Among 10 012 major trauma patients included in the study cohort, 28.8% (n = 2880) were women. The PSM patient group consisted of 50% (2876 of 5752) women. Women had a higher 30-day (15.4% of women vs 13.8% of men; p < 0.05) and hospital (16.1% of women vs 14.5% of men; p < 0.05) mortality and lower incidence rates of acute respiratory dysfunction (62.5% of women vs 65.9% of men; p < 0.005) and acute hepatic dysfunction (0.8% of women vs 2.1% of men; p < 0.001). However, the analysis of PSM patient groups showed lower mortality rates in women with moderate trauma (NISS 16-24) in the acute phase within three days (1.4% of women vs 2.7% of men, p = 0.03). Analysis of patients with an NISS of 16-24 who died within three days showed a higher NISS in women than in men (19.7 ± 2.3 vs 18.0 ±1.9, respectively, p <0.05). CONCLUSION: There is no gender difference in 30-day or hospital mortality among major trauma patients. However, women admitted for moderate major trauma had higher survival within three days of major trauma.


Asunto(s)
Mortalidad Hospitalaria , Factores Sexuales , Índices de Gravedad del Trauma , Heridas y Lesiones/mortalidad , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Tasa de Supervivencia , Taiwán
8.
PLoS One ; 14(2): e0198230, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30726204

RESUMEN

Globally, pangolins are threatened by poaching and illegal trade. Taiwan presents a contrary situation, where the wild pangolin population has stabilized and even begun to increase in the last two decades. This paper illustrates the factors responsible for causing mortality and morbidity in the wild Taiwanese pangolin (Manis pentadactyla pentadactyla) based on radio-tracking data of wild pangolins and records of sick or injured pangolins admitted to a Taiwanese wildlife rehabilitation center. Despite being proficient burrowers, results from radio-tracking show that Taiwanese pangolins are highly susceptible to getting trapped in tree hollows or ground burrows. Data from Pingtung Rescue Center for Endangered Wild Animals showed that trauma (73.0%) was the major reason for morbidity in the Taiwanese pangolin with trauma from gin traps being the leading cause (77.8%), especially during the dry season, followed by tail injuries caused by dog attacks (20.4%). Despite these threats, Taiwan has had substantial success in rehabilitating and releasing injured pangolins, primarily due to the close collaboration of Taiwanese wildlife rehabilitation centers over the last twenty years.


Asunto(s)
Conservación de los Recursos Naturales/métodos , Animales , Animales Salvajes , Carnívoros , Mamíferos , Morbilidad , Mortalidad , Taiwán , Xenarthra/metabolismo
9.
Cell Death Dis ; 8(11): e3167, 2017 11 09.
Artículo en Inglés | MEDLINE | ID: mdl-29120412

RESUMEN

MicroRNAs (miRNAs) have been suggested to repress transcription via binding the 3'-untranslated regions of mRNAs. However, the involvement and details of miRNA-mediated epigenetic regulation, particularly in targeting genomic DNA and mediating epigenetic regulation, remain largely uninvestigated. In the present study, transcription factor CCAAT/enhancer binding protein delta (CEBPD) was responsive to the anticancer drug bortezomib, a clinical and highly selective drug for leukemia treatment, and contributed to bortezomib-induced cell death. Interestingly, following the identification of CEBPD-induced miRNAs, we found that miR-744, miR-3154 and miR-3162 could target CpG islands in the 5'-flanking region of the CEBPD gene. We previously demonstrated that the Yin Yang 1 (YY1)/polycomb group (PcG) protein/DNA methyltransferase (DNMT) complex is important for CCAAT/enhancer binding protein delta (CEBPD) gene inactivation; we further found that Argonaute 2 (Ago2) interacts with YY1 and binds to the CEBPD promoter. The miRNA/Ago2/YY1/PcG group protein/DNMT complex linked the inactivation of CEBPD and genes adjacent to its 5'-flanking region, including protein kinase DNA-activated catalytic polypeptide (PRKDC), minichromosome maintenance-deficient 4 (MCM4) and ubiquitin-conjugating enzyme E2 variant 2 (UBE2V2), upon bortezomib treatment. Moreover, we revealed that miRNA binding is necessary for YY1/PcG group protein/DNMT complex-mediated epigenetic gene silencing and is associated with bortezomib-induced methylation on genomic DNA. The present study successfully characterized the interactions of the miRNA/Ago2/YY1/PcG group protein/DNMT complex and provided new insights for miRNA-mediated epigenetic regulation in bortezomib-induced leukemic cell arrest and cell death.


Asunto(s)
Apoptosis/efectos de los fármacos , Bortezomib/farmacología , Leucemia/fisiopatología , MicroARNs/metabolismo , Regiones no Traducidas 3' , Antineoplásicos/farmacología , Proteínas Argonautas/química , Proteínas Argonautas/metabolismo , Proteína delta de Unión al Potenciador CCAAT/genética , Proteína delta de Unión al Potenciador CCAAT/metabolismo , Línea Celular Tumoral , Islas de CpG , Metilación de ADN/efectos de los fármacos , Proteína Quinasa Activada por ADN/genética , Proteína Quinasa Activada por ADN/metabolismo , Silenciador del Gen , Humanos , Leucemia/metabolismo , Ligasas/genética , Ligasas/metabolismo , MicroARNs/genética , Componente 4 del Complejo de Mantenimiento de Minicromosoma/genética , Componente 4 del Complejo de Mantenimiento de Minicromosoma/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Regiones Promotoras Genéticas , Unión Proteica , Transcripción Genética/efectos de los fármacos , Enzimas Ubiquitina-Conjugadoras , Factor de Transcripción YY1/química , Factor de Transcripción YY1/metabolismo
10.
Anal Chem ; 89(17): 8748-8756, 2017 09 05.
Artículo en Inglés | MEDLINE | ID: mdl-28774174

RESUMEN

Leakage of lead and other heavy metals into drinking water is a significant health risk and one that is not easily detected. We have developed simple sensors containing only platinum electrodes for the detection of heavy metal contamination in drinking water. The two-electrode sensor can identify the existence of a variety of heavy metals in drinking water, and the four-electrode sensor can distinguish lead from other heavy metals in solution. No false-positive response is generated when the sensors are placed in simulated and actual tap water contaminated by heavy metals. Lead detection on the four-electrode sensor is not affected by the presence of common ions in tap water. Experimental results suggest the sensors can be embedded in water service lines for long-time use until lead or other heavy metals are detected. With its low cost (∼$0.10/sensor) and the possibility of long-term operation, the sensors are ideal for heavy metal detection of drinking water.


Asunto(s)
Agua Potable/análisis , Técnicas Electroquímicas/instrumentación , Plomo/análisis , Contaminantes Químicos del Agua/análisis , Impedancia Eléctrica , Técnicas Electroquímicas/economía , Técnicas Electroquímicas/métodos , Electrodos , Platino (Metal)/química
11.
PLoS One ; 12(8): e0183187, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28806401

RESUMEN

Growth differentiation factor 15 (GDF15) is a strong predictor of cardiovascular events and mortality in individuals with or without cardiovascular diseases. Single nucleotide polymorphisms (SNPs) in microRNA (miRNA) target sites, also known as miRSNPs, are known to enhance or weaken miRNA-mRNA interactions and have been linked to diseases such as cardiovascular disease and cancer. In this study, we aimed to elucidate the functional significance of the miRSNP rs1054564 in regulating GDF15 levels. Two rs1054564-containing binding sites for hsa-miR-873-5p and hsa-miR-1233-3p were identified in the 3' untranslated region (UTR) of the GDF15 transcript using bioinformatics tools. Their activities were further characterized by in vitro reporter assays. Bioinformatics prediction suggested that miRNA binding sites harboring the rs1054564-G allele had lower free energies than those with the C allele and therefore were better targets with higher affinities for both hsa-miR-873-5p and hsa-miR-1233-3p. Reporter assays showed that luciferase activity was significantly decreased by rs1054564-G-containing 3' UTRs for both miRNAs (P < 0.05) and was restored by miRNA inhibitors. Comparing the fold suppression of the two miRNAs, only that of hsa-miR-1233-3p showed significant changes between the rs1054564-G- and C-containing 3' UTRs (P = 0.034). In addition, western blots showed that transfection of both miRNA mimics significantly decreased endogenous GDF15 expression in a melanoma cell line (P < 0.05). Taken together, our findings demonstrate that GDF15 is a target of hsa-miR-873-5p and hsa-miR-1233-3p and that the rs1054564-C allele partially abolishes hsa-miR-1233-3p-mediated translational suppression of GDF15. These results suggest that rs1054564 confers allele-specific translational repression of GDF15 via hsa-miR-1233-3p. Our work thus provides biological insight into the previously reported clinical association between rs1054564 and plasma GDF15 levels.


Asunto(s)
Regiones no Traducidas 3'/genética , Alelos , Factor 15 de Diferenciación de Crecimiento/genética , MicroARNs/metabolismo , Polimorfismo de Nucleótido Simple/genética , Biosíntesis de Proteínas/genética , Secuencia de Bases , Sitios de Unión/genética , Línea Celular Tumoral , Simulación por Computador , Factor 15 de Diferenciación de Crecimiento/metabolismo , Células HEK293 , Humanos , MicroARNs/química , MicroARNs/genética , Conformación de Ácido Nucleico
12.
Sensors (Basel) ; 17(7)2017 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-28753913

RESUMEN

Monitoring of the pH, oxidation-reduction-potential (ORP), and conductivity of aqueous samples is typically performed using multiple sensors. To minimize the size and cost of these sensors for practical applications, we have investigated the use of a single sensor constructed with only bare platinum electrodes deposited on a glass substrate. The sensor can measure pH from 4 to 10 while simultaneously measuring ORP from 150 to 800 mV. The device can also measure conductivity up to 8000 µS/cm in the range of 10 °C to 50 °C, and all these measurements can be made even if the water samples contain common ions found in residential water. The sensor is inexpensive (i.e., ~$0.10/unit) and has a sensing area below 1 mm², suggesting that the unit is cost-efficient, robust, and widely applicable, including in microfluidic systems.

13.
Comput Math Methods Med ; 2017: 2750701, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28634497

RESUMEN

Inspiratory flow limitation (IFL) is a critical symptom of sleep breathing disorders. A characteristic flattened flow-time curve indicates the presence of highest resistance flow limitation. This study involved investigating a real-time algorithm for detecting IFL during sleep. Three categories of inspiratory flow shape were collected from previous studies for use as a development set. Of these, 16 cases were labeled as non-IFL and 78 as IFL which were further categorized into minor level (20 cases) and severe level (58 cases) of obstruction. In this study, algorithms using polynomial functions were proposed for extracting the features of IFL. Methods using first- to third-order polynomial approximations were applied to calculate the fitting curve to obtain the mean absolute error. The proposed algorithm is described by the weighted third-order (w.3rd-order) polynomial function. For validation, a total of 1,093 inspiratory breaths were acquired as a test set. The accuracy levels of the classifications produced by the presented feature detection methods were analyzed, and the performance levels were compared using a misclassification cobweb. According to the results, the algorithm using the w.3rd-order polynomial approximation achieved an accuracy of 94.14% for IFL classification. We concluded that this algorithm achieved effective automatic IFL detection during sleep.


Asunto(s)
Algoritmos , Técnicas de Diagnóstico del Sistema Respiratorio , Síndromes de la Apnea del Sueño/diagnóstico , Humanos , Respiración
14.
Nanoscale Res Lett ; 9(1): 476, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25258602

RESUMEN

Sensitivity of surface plasmon resonance phase-interrogation biosensor is demonstrated to be enhanced by oblique deposited silver nanorods. Silver nanorods are thermally deposited on silver nanothin film by oblique angle deposition (OAD). The length of the nanorods can be tuned by controlling the deposition parameters of thermal deposition. By measuring the phase difference between the p and s waves of surface plasmon resonance heterodyne interferometer with different wavelength of incident light, we have demonstrated that maximum sensitivity of glucose detection down to 7.1 × 10(-8) refractive index units could be achieved with optimal deposition parameters of silver nanorods.

15.
PLoS One ; 9(2): e89379, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24586733

RESUMEN

Lymphopenia-induced proliferation (LIP), a mechanism to maintain a constant number of T cells in circulation, occurs in both normal aging and autoimmune disease. The incidence of most autoimmune diseases increases with age, and premature CD4(+) T cell aging has been reported in several autoimmune diseases. In this study, we tested the hypothesis that premature CD4(+) T cell aging can cause autoimmune disease by examining whether premature CD4(+) T cell aging exists and causes LIP in our mouse model. Non-obese diabetic (NOD) mice were used because, in addition to Treg defects, the LIP of T cells has been shown to plays a causative role in the development of insulin-dependent diabetes mellitus (IDDM) in these mice. We found that with advancing age, NOD mice exhibited an accelerated decrease in the number of CD4(+) T cells due to the loss of naïve cells. This was accompanied by an increase in the percentage of memory cells, leading to a reduced naïve/memory ratio. In addition, both the percentage of CD28(+) cells in CD4(+) T cells and IL-2 production decreased, while the percentage of FAS(+)CD44(+) increased, suggesting that NOD mice exhibit premature CD4(+) T cell aging. This process preferentially contributed to LIP of memory cells. Therefore, our results suggest that premature CD4(+) T cell aging underlies the development of IDDM in NOD mice. Given that CD28 and IL-2 play important roles in Treg function, the relationships between premature CD4(+) T cell aging and lymphopenia as well as Treg defects in autoimmune-prone NOD mice are proposed.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Proliferación Celular , Senescencia Celular , Diabetes Mellitus Experimental/inmunología , Memoria Inmunológica , Linfopenia/inmunología , Animales , Antígenos CD28/inmunología , Linfocitos T CD4-Positivos/citología , Femenino , Interleucina-2/biosíntesis , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos NOD , Obesidad
16.
Int J Cancer ; 134(3): 542-51, 2014 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-23904094

RESUMEN

Drug resistance is an obstacle to the treatment of ovarian cancer. Using a unique cell model, we have proven previously that a subpopulation of ovarian cancer cells is more resistant to cisplatin than are the original cells. MicroRNAs (miRNAs), small noncoding RNAs, are involved in many biological events in cancer cells. In our study, we explored whether miRNAs are involved in cisplatin resistance of ovarian cancer cells. Cisplatin-resistant cells expressed a lower level of miR-29a/b/c. Manipulation of microRNA-29 (miR-29) expression modulated cisplatin sensitivity of CP70, HeyC2, SKOV3 and A2780 ovarian cancer cells. Knockdown of miR-29a/b/c increased the ability of cells to escape cisplatin-induced cell death partly through upregulation of collagen type I alpha 1 (COL1A1) and increased the activation of extracellular signal-regulated kinase 1/2 and inactivation of glycogen synthase kinase 3 beta. When combined with cisplatin treatment, knockdown of miR-29 decreased the amount of the active form of caspase-9 and caspase-3. Ectopic expression of miR-29 alone or in combination with cisplatin treatment efficaciously reduced the tumorigenicity of CP70 cells in vivo. Our data show that downregulation of miR-29 increases cisplatin resistance in ovarian cancer cells. Taken together, these data suggest that overexpression of miR-29 is a potential sensitizer to cisplatin treatment that may have therapeutic implications.


Asunto(s)
Antineoplásicos/uso terapéutico , Cisplatino/uso terapéutico , Regulación hacia Abajo , MicroARNs/fisiología , Neoplasias Ováricas/genética , Línea Celular Tumoral , Colágeno Tipo I/fisiología , Cadena alfa 1 del Colágeno Tipo I , Resistencia a Antineoplásicos , Femenino , Humanos , MicroARNs/genética , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/patología
17.
Biochim Biophys Acta ; 1833(12): 3206-3217, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24018208

RESUMEN

We have reported previously that LIM homeobox transcription factor 1α (LMX1A) is hypermethylated and functions as a metastasis suppressor in cervical cancer cells. However, the regulation of LMX1A in carcinogenesis has not been reported. We aim to clarify whether specificity protein 1 (Sp1) and enhancer of zeste homolog 2 (EZH2) are involved in the regulation of LMX1A in cervical cancer. First we characterized the LMX1A promoter and used overexpression, knockdown, and reporter assays to show that Sp1 increased LMX1A promoter activity. Next, we used site-directed mutagenesis and electrophoresis mobility shift assays (EMSAs) to demonstrate that Sp1-binding sites were important for Sp1-mediated activation of the LMX1A promoter. Chromatin immunoprecipitation data demonstrated that Sp1 could bind directly to the LMX1A promoter and activate endogenous LMX1A expression in cells pretreated with 5-aza-2'-deoxycytidine (5-aza-dC). Knockdown of EZH2 decreased H3K27me3 histone modification but was insufficient to restore LMX1A expression. To explore the effect of EZH2 on the endogenous LMX1A promoter, we treated EZH2-knockdown cells with 5-aza-dC and trichostatin A (TSA) and then depleted the cells of drugs for 3days. H3K14ac was enriched at the LMX1A promoter in EZH2-knockdown cells and LMX1A mRNA was still expressed. Taken together, these data imply that Sp1 may activate LMX1A expression upon oncogenic stress during cervical cancer development. Moreover, suppression of EZH2 may delay resilencing of LMX1A after the removal of 5-aza-dC and TSA.


Asunto(s)
Proteínas con Homeodominio LIM/genética , Complejo Represivo Polycomb 2/metabolismo , Factor de Transcripción Sp1/metabolismo , Factores de Transcripción/genética , Neoplasias del Cuello Uterino/genética , Azacitidina/farmacología , Secuencia de Bases , Sitios de Unión , Línea Celular Tumoral , Proteína Potenciadora del Homólogo Zeste 2 , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Técnicas de Silenciamiento del Gen , Silenciador del Gen/efectos de los fármacos , Inhibidores de Histona Desacetilasas/farmacología , Histonas/metabolismo , Humanos , Proteínas con Homeodominio LIM/metabolismo , Metilación/efectos de los fármacos , Datos de Secuencia Molecular , Regiones Promotoras Genéticas/genética , Unión Proteica/genética , Factor de Transcripción Sp1/antagonistas & inhibidores , Factores de Transcripción/metabolismo
18.
Hepatology ; 56(6): 2277-87, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22767186

RESUMEN

UNLABELLED: Oncogenic activation of the Wnt/ß-catenin signaling pathway is common in hepatocellular carcinoma (HCC). Our recent studies have demonstrated that SRY (sex determining region Y)-box 1 (SOX1) and secreted frizzled-related proteins are concomitantly promoter-hypermethylated, and this might lead to abnormal activation of the Wnt signaling pathway in HCC. SOX1 encodes a transcription factor involved in the regulation of embryonic development and cell fate determination. However, the expression and functional role of SOX1 in HCC remains unclear. In this study, we confirmed via quantitative methylation-specific polymerase chain reaction that SOX1 was frequently downregulated through promoter hypermethylation in HCC cells and tissues. Overexpression of SOX1 by a constitutive or inducible approach could suppress cell proliferation, colony formation, and invasion ability in HCC cell lines, as well as tumor growth in nonobese diabetic/severe combined immunodeficiency mice. Conversely, knockdown of SOX1 by withdrawal of doxycycline could partially restore cell proliferation and colony formation in HCC cells. We used a T cell factor (TCF)-responsive luciferase reporter assay and western blot analysis to prove that SOX1 could regulate TCF-responsive transcriptional activity and inhibit the expression of Wnt downstream genes. Furthermore, we used glutathione S-transferase pull-down, co-immunoprecipitation, and confocal microscopy to demonstrate that SOX1 could interact with ß-catenin but not with the ß-catenin/TCF complex. Moreover, restoration of the expression of SOX1 induces significant cellular senescence in Hep3B cells. CONCLUSION: Our data show that a developmental gene, SOX1, may function as a tumor suppressor by interfering with Wnt/ß-catenin signaling in the development of HCC.


Asunto(s)
Carcinoma Hepatocelular/genética , Genes Supresores de Tumor , Neoplasias Hepáticas/genética , Factores de Transcripción SOXB1/genética , Factores de Transcripción SOXB1/metabolismo , Vía de Señalización Wnt , Animales , Antibacterianos/farmacología , Antígenos CD , Cadherinas/genética , Cadherinas/metabolismo , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Puntos de Control del Ciclo Celular , Proliferación Celular , Ciclina D1/genética , Ciclina D1/metabolismo , Quinasa 4 Dependiente de la Ciclina/metabolismo , Quinasa 6 Dependiente de la Ciclina/metabolismo , Metilación de ADN , Regulación hacia Abajo , Doxiciclina/farmacología , Genes bcl-1 , Genes myc , Células Hep G2 , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Ratones , Ratones Endogámicos NOD , Ratones SCID , Antígeno Nuclear de Célula en Proliferación/metabolismo , Regiones Promotoras Genéticas , Proteínas Proto-Oncogénicas c-myc/genética , Proteínas Proto-Oncogénicas c-myc/metabolismo , Proteínas Proto-Oncogénicas p21(ras)/metabolismo , ARN Mensajero/metabolismo , Factores de Transcripción SOXB1/efectos de los fármacos , Factores de Transcripción de la Familia Snail , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
19.
Mol Immunol ; 47(16): 2552-62, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20801512

RESUMEN

Decoy receptor 3 (DcR3), a member of the tumor necrosis factor receptor superfamily, regulates immune responses through competing with receptors of Fas ligand (FasL), LIGHT and TNF-like molecule 1A (TL1A). We have previously demonstrated that transgenic expression of DcR3 in a ß cell-specific manner significantly protects non-obese diabetic (NOD) mice from autoimmune diabetes. In this study, we further investigated the systemic effect of DcR3 in regulating lymphocytes and dendritic cells in NOD mice. Our results demonstrated that both DcR3 plasmid and protein treatments significantly inhibited insulitis and diabetes. Lymphocytes from DcR3.Fc-treated mice revealed less proliferative potential and transferred ameliorated diabetes. By administration of DcR3.Fc in T1 and T2 double transgenic NOD mice expressing human Thy1 or murine Thy1.1 surface marker under IFN-γ or IL-4 promoter control respectively, we observed a remarkable reduction of Th1 and an increase of Th2 immune responses in vivo. Strikingly, in vitro polarization experiments exhibited that not only Th1 but also Th17 cell differentiation was significantly inhibited in splenocytes treated with DcR3.Fc protein. However, this phenomenon was only observed in splenocytes, not in purified CD4(+) T cells, suggesting that DcR3-mediated inhibition of Th1 and Th17 differentiation is not T cell-autonomous and maybe through other cell types such as dendritic cells. Finally, our results demonstrated that DcR3 directly modulates the differentiation and maturation of dendritic cells and subsequently regulates the differentiation and effector function of T cells.


Asunto(s)
Diferenciación Celular , Células Dendríticas/inmunología , Diabetes Mellitus Tipo 1/inmunología , Miembro 6b de Receptores del Factor de Necrosis Tumoral/inmunología , Animales , Polaridad Celular , Células Cultivadas , Células Dendríticas/citología , Femenino , Masculino , Ratones , Ratones Endogámicos NOD , Bazo/inmunología , Linfocitos T Colaboradores-Inductores/citología , Linfocitos T Colaboradores-Inductores/inmunología
20.
Int J Cancer ; 127(3): 555-67, 2010 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-19957335

RESUMEN

Oncogenic activation of the Wnt signaling pathway is common in cancers, but mutation of beta-catenin in ovarian cancer is rare. In addition to genetic events, epigenetic modification of secreted frizzled-related protein (SFRP) family has been shown to be important in regulating Wnt signaling. Although high degree of homology is observed in the same family, different SFRPs may have opposing effects on the same process. We reported recently that a Wnt antagonist, SFRP5, is downregulated frequently through promoter hypermethylation and that this hypermethylation is associated with overall survival in ovarian cancer. The aim of this study was to analyze the function of SFRP5 in ovarian cancer. Functional assays including measuring cell proliferation, invasion, colony formation and xenograft were performed using ovarian cancer cell lines with overexpression of SFRP5 or a short hairpin RNA silencing. The methylation status of SFRP5 in relation to cisplatin resistance in ovarian cancer patients was analyzed. Restoration of the expression of SFRP5 attenuated Wnt signaling in ovarian cancer cells and suppressed cancer cell growth, invasion of cells and tumorigenicity in mice. These effects were independent of the canonical pathway. The expression of SFRP5 inhibited epithelial-mesenchymal transition (EMT). The restoration of SFRP5 downregulated AKT2 and sensitized ovarian cancer cells to chemotherapy. These effects are consistent with the poor response to platinum-based chemotherapy in patients with methylation of SFRP5. Our data suggested that epigenetic silencing of SFRP5 leads to oncogenic activation of the Wnt pathway and contributes to ovarian cancer progression and chemoresistance through the TWIST-mediated EMT and AKT2 signaling.


Asunto(s)
Epigénesis Genética , Proteínas del Ojo/genética , Silenciador del Gen , Proteínas de la Membrana/genética , Neoplasias Ováricas/genética , Transducción de Señal , Proteínas Wnt/metabolismo , Proteínas Adaptadoras Transductoras de Señales , Antineoplásicos/farmacología , Secuencia de Bases , Western Blotting , Cisplatino/farmacología , Metilación de ADN , Cartilla de ADN , Resistencia a Antineoplásicos , Femenino , Técnica del Anticuerpo Fluorescente , Humanos , Neoplasias Ováricas/metabolismo , Fenotipo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
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