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1.
Appl Opt ; 63(10): 2429-2435, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38568521

RESUMEN

A multifunction processor for a broadband signal based on the active mode-locking optoelectronic oscillator (OEO) is proposed and experimentally demonstrated. The central frequency down-conversion and frequency spectrum convolution of the target broadband signal (TBS) are realized by just tuning the wavelength of the optical carrier or by the time domain product, respectively. To achieve the central frequency down-conversion of the TBS, an optical tunable delay line (OTDL) is adopted to match the delay time of the OEO loop with the repetition period of the TBS. Then the spectrum convolution of the TBS is produced by just injecting a lower frequency signal consistent with the free spectral range (FSR) of the OEO loop. Moreover, the frequency convolution repetition is also greatly increased by harmonic mode-locking injection. The equivalent bandwidth of the TBS is enlarged by ∼50 times, benefiting from the frequency convolution. The central frequency conversion flexibility and the bandwidth compatibility are also discussed in detail. This work provides a multifunction processor system and may have potential usage in multifunctional integrated radar systems.

2.
BMC Public Health ; 24(1): 1812, 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38972984

RESUMEN

BACKGROUND: Smoking rationalisation beliefs are a huge barrier to quitting smoking. What types of rationalisations should be emphasised in smoking cessation interventions? Although past literature has confirmed the negative relationship between those beliefs and motivation to stop smoking, little is known regarding the importance and performance of those beliefs on motivation with varying cigarette dependence. The study aimed to ascertain rationalisations that are highly important for motivation yet perform poorly in different cigarette dependence groups. METHODS: The cross-sectional study was conducted from November 19 to December 9, 2023 in Guiyang City, China. Adult male current smokers were enrolled. Partial least squares structural equation modelling was used to test the hypothesis. The multi-group analysis was used to determine the moderating effect of cigarette dependence, and the importance-performance map analysis was utilised to assess the importance and performance of rationalisations. RESULTS: A total of 616 adult male current smokers were analysed, and they were divided into the low cigarette dependence group (n = 297) and the high cigarette dependence group (n = 319). Except for risk generalisation beliefs, smoking functional beliefs (H1: -ß = 0.131, P < 0.01), social acceptability beliefs (H3: ß = -0.258, P < 0.001), safe smoking beliefs (H4: ß = -0.078, P < 0.05), self-exempting beliefs (H5: ß = -0.244, P < 0.001), and quitting is harmful beliefs (H6: ß = -0.148, P < 0.01) all had a significant positive influence on motivation. Cigarette dependence moderated the correlation between rationalisations and motivation. In the high-dependence group, the social acceptability beliefs and smoking functional beliefs were located in the "Concentrate Here" area. In the low-dependence group, the social acceptability beliefs were also situated in there. CONCLUSIONS: Social acceptability beliefs and smoking functional beliefs showed great potential and value for improvement among high-dependence smokers, while only social acceptability beliefs had great potential and value for improvement among low-dependence smokers. Addressing these beliefs will be helpful for smoking cessation. The multi-group analysis and the importance-performance map analysis technique have practical implications and can be expanded to other domains of health education and intervention practice.


Asunto(s)
Motivación , Cese del Hábito de Fumar , Humanos , Masculino , China , Estudios Transversales , Adulto , Cese del Hábito de Fumar/psicología , Persona de Mediana Edad , Fumadores/psicología , Fumadores/estadística & datos numéricos , Conocimientos, Actitudes y Práctica en Salud , Adulto Joven , Tabaquismo/psicología , Tabaquismo/terapia , Pueblos del Este de Asia
3.
Prostate ; 83(1): 97-108, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36164668

RESUMEN

BACKGROUND: The PI3K/AKT/mTOR signaling pathway is essential for initiation and progression of prostate cancer. However, there has been no a comprehensive comparison for the role of these signaling nodes in prostate tumor initiation and progression. METHODS: With genetically engineered animal models, we compared the impact of prostate-specific deletions of Pten, Tsc1, and Tsc2 and activation of Akt1 on tumor initiation and progression. Also, we assessed the expression and genetic alterations of PTEN, AKT1, TSC1, and TSC2 in human primary prostate cancers. RESULTS: For the genetically engineered mice, prostate conditional knockout (cKO) of Pten, Tsc1, and Tsc2 led to initiation and progression of mouse prostatic neoplasia hyperplasia (mPIN). Akt1 transgenic mice developed more aggressive mPINs than mice with Tsc1 or Tsc2 single-cKO, but the effect was more moderate than that for Pten single-cKO or Tsc1/Tsc2 double-cKO mice. Functional analyses showed that Pten single-cKO, AKT1 activation, and Tsc1/Tsc2 double-cKO induced cell proliferation more than Tsc1 or Tsc2 single-cKO, but only Pten single-cKO and AKT1 activation reduced epithelial adhesion. All cKO or AKT1 activation enhanced the phosphorylation of p-S6 (S235/236) but only Pten single-cKO and Tsc1/Tsc2 double-cKO enhanced the phosphorylation of p-AKT (S473) and p-4EBP1 (T37/46/70). In human prostate cancers, PTEN, but not AKT1, TSC1, or TSC2 had frequent genetic alterations. However, as key signaling nodes, AKT1, TSC1, and TSC2 may be responsible for PTEN loss-mediated tumor initiation and progression. CONCLUSION: Our results for genetically engineered mouse models suggest a differential role of the PI3K/AKT/mTOR signaling nodes in prostate cancer initiation and progression, but the underlying molecular mechanisms remain unaddressed.


Asunto(s)
Fosfatidilinositol 3-Quinasas , Neoplasias de la Próstata , Masculino , Humanos , Ratones , Animales , Mutación , Transducción de Señal , Neoplasias de la Próstata/genética , Modelos Animales , Serina-Treonina Quinasas TOR
4.
Mol Cell ; 57(4): 708-720, 2015 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-25639470

RESUMEN

mTOR senses nutrient and energy status to regulate cell survival and metabolism in response to environmental changes. Surprisingly, targeted mutation of Tsc1, a negative regulator of mTORC1, caused a broad reduction in miRNAs due to Drosha degradation. Conversely, targeted mutation of Raptor, an essential component of mTORC1, increased miRNA biogenesis. mTOR activation increased expression of Mdm2, which is hereby identified as the necessary and sufficient ubiquitin E3 ligase for Drosha. Drosha was induced by nutrient and energy deprivation and conferred resistance to glucose deprivation. Using a high-throughput screen of a miRNA library, we identified four miRNAs that were necessary and sufficient to protect cells against glucose-deprivation-induced apoptosis. These miRNA was regulated by glucose through the mTORC1-MDM2-DROSHA axis. Taken together, our data reveal an mTOR-Mdm2-Drosha pathway in mammalian cells that broadly regulates miRNA biogenesis as a response to alteration in cellular environment.


Asunto(s)
MicroARNs/biosíntesis , Complejos Multiproteicos/fisiología , Proteínas Proto-Oncogénicas c-mdm2/fisiología , Ribonucleasa III/fisiología , Serina-Treonina Quinasas TOR/fisiología , Aminoácidos/metabolismo , Animales , Regulación de la Expresión Génica , Glucosa/metabolismo , Células HeLa , Humanos , Diana Mecanicista del Complejo 1 de la Rapamicina , Ratones Endogámicos C57BL , Complejos Multiproteicos/genética , Complejos Multiproteicos/metabolismo , Proteolisis , Proteínas Proto-Oncogénicas c-mdm2/genética , Proteínas Proto-Oncogénicas c-mdm2/metabolismo , Ribonucleasa III/genética , Ribonucleasa III/metabolismo , Serina-Treonina Quinasas TOR/genética , Serina-Treonina Quinasas TOR/metabolismo , Proteína p53 Supresora de Tumor/fisiología , Ubiquitinación
5.
J Med Internet Res ; 25: e48838, 2023 12 13.
Artículo en Inglés | MEDLINE | ID: mdl-37990370

RESUMEN

BACKGROUND: The eHealth Literacy Scale (eHEALS) was introduced in China in 2013 as one of the most important electronic health literacy measurement instruments. After a decade of development in China, it has received widespread attention, although its theoretical underpinnings have been challenged, thus demanding more robust research evidence of factorial validity and multigroup measurement properties. OBJECTIVE: This study aimed to evaluate the Chinese version of the eHEALS in terms of its measurement properties. METHODS: A cross-sectional survey was conducted in a university setting in China. Item statistics were checked for response distributions and floor and ceiling effects. Internal consistency reliability was confirmed with Cronbach α, split-half reliability, Cronbach α if an item was deleted, and item-total correlation. A total of 5 representative eHEALS factor structures were examined and contrasted using confirmatory factor analysis. The study used the item-level content validity index (I-CVI) and the average of the I-CVI scores of all items on the scale to assess the content validity of the dominance model. Furthermore, the validated dominance model was subsequently used to evaluate the relevance and representation of elements in the instrument and to assess measurement invariance across genders. RESULTS: A total of 972 respondents were identified, with a Cronbach α of .92, split-half reliability of 0.88, and item-total score correlation coefficients ranging from 0.715 to 0.781. Cronbach α if an item was deleted showed that all items should be retained. Acceptable content validity was supported by I-CVIs ≥0.80. The confirmatory factor analysis confirmed that the 3-factor model was acceptable. The measurement model met all relevant fit indices: average variance extracted from 0.663 to 0.680, composite reliability from 0.810 to 0.857, chi-square divided by the df of 4.768, root mean square error of approximation of 0.062, standardized root mean squared residual of 0.020, comparative fit index (CFI) of 0.987, and Tucker-Lewis index of 0.979. In addition, the scale demonstrated error variance invariance (Δnormed fit index=-0.016, Δincremental fit index=-0.012, ΔTucker-Lewis index=0.005, Δcomparative fit index=-0.012, Δrelative fit index=0.005, and Δroot mean square error of approximation=0.005). CONCLUSIONS: A 3-factor model of the Chinese version of the eHEALS fits best, and our findings provide evidence for the strict measurement invariance of the instrument regarding gender.


Asunto(s)
Alfabetización en Salud , Telemedicina , Humanos , Masculino , Femenino , Estudios Transversales , Reproducibilidad de los Resultados , Estudiantes , Encuestas y Cuestionarios , Psicometría
6.
Mol Cancer ; 21(1): 38, 2022 02 07.
Artículo en Inglés | MEDLINE | ID: mdl-35130925

RESUMEN

BACKGROUND: Unlike autosomal tumor suppressors, X-linked tumor suppressors can be inactivated by a single hit due to X-chromosome inactivation (XCI). Here, we argue that targeted reactivation of the non-mutated allele from XCI offers a potential therapy for female breast cancers. METHODS: Towards this goal, we developed a dual CRISPR interference and activation (CRISPRi/a) approach for simultaneously silencing and reactivating multiple X-linked genes using two orthogonal, nuclease-deficient CRISPR/Cas9 (dCas9) proteins. RESULTS: Using Streptococcus pyogenes dCas9-KRAB for silencing XIST and Staphylococcus aureus dCas9-VPR for activating FOXP3, we achieved CRISPR activation of FOXP3 in various cell lines of human female breast cancers. In human breast cancer HCC202 cells, which express a synonymous heterozygous mutation in the coding region of FOXP3, simultaneous silencing of XIST from XCI led to enhanced and prolonged FOXP3 activation. Also, reactivation of endogenous FOXP3 in breast cancer cells by CRISPRi/a inhibited tumor growth in vitro and in vivo. We further optimized CRISPRa by fusing dCas9 to the demethylase TET1 and observed enhanced FOXP3 activation. Analysis of the conserved CpG-rich region of FOXP3 intron 1 confirmed that CRISPRi/a-mediated simultaneous FOXP3 activation and XIST silencing were accompanied by elevated H4 acetylation, including H4K5ac, H4K8ac, and H4K16ac, and H3K4me3 and lower DNA methylation. This indicates that CRISPRi/a targeting to XIST and FOXP3 loci alters their transcription and their nearby epigenetic modifications. CONCLUSIONS: The simultaneous activation and repression of the X-linked, endogenous FOXP3 and XIST from XCI offers a useful research tool and a potential therapeutic for female breast cancers.


Asunto(s)
Neoplasias de la Mama , Genes Ligados a X , Neoplasias de la Mama/genética , Línea Celular , Metilación de ADN , Femenino , Factores de Transcripción Forkhead/genética , Humanos , Oxigenasas de Función Mixta , Proteínas Proto-Oncogénicas
7.
Biomed Chromatogr ; 36(1): e5251, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34606105

RESUMEN

Osmundacetone is a potential medicinal substance existing in ferns and has excellent antioxidant effects. This research aims to obtain the pharmacokinetic data for and metabolite products of osmundacetone. An UPLC-MS/MS quantitative method was established for the measurement of osmundacetonein in rat plasma over a linear range of 6.72-860.00 ng/ml. The signal to noise ratio of the lower limit of quantification was 60:1, the precision was <9.74% and the method had good selectivity and stability. The established method was successfully applied to the pharmacokinetic study of osmundacetone for the first time. Osmundacetone reached a peak at 0.25 h with a maximum value of 3283.33 µg/L. The apparent volume of distribution not multiplied by the bioavailability was 127.96 L/kg, and the half-life of osmundacetone was 5.20 h. At the same time, an UPLC-QE-Orbitrap-HRMS method was established to identify metabolites in plasma, urine and feces for the first time. A total of 30 metabolites were identified and the metabolic profile of osmundacetone was defined. In general, we have established a mass spectrometry quantitative method for osmundacetone for the first time and characterized its metabolic characteristics in rats.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Cetonas , Espectrometría de Masas en Tándem/métodos , Animales , Cetonas/sangre , Cetonas/química , Cetonas/farmacocinética , Límite de Detección , Modelos Lineales , Masculino , Ratas , Ratas Wistar , Reproducibilidad de los Resultados
8.
Biomed Chromatogr ; 36(4): e5341, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35045589

RESUMEN

Neurotransmitters play an important role in regulating the physiological activity of the animal, especially in emotion and sleep, whereas nucleotides are involved in almost all cellular processes. However, the characteristics of sleep-related neurochemicals under different life cycles and environments remain poorly understood. A rapid and sensitive analytical method was established with LC-MS/MS to determine eight endogenous neurochemicals in Drosophila melanogaster, and their levels in the different developmental stages of D. melanogaster were evaluated. The results indicated that there were significant discrepancies among different stages, especially from the pupal stage to the adult stage. The levels of these compounds in the caffeine-induced insomnia model of D. melanogaster were investigated. Compared with the normal group, the eight endogenous metabolites did not fluctuate significantly in insomnia D. melanogaster, which may be due to the mechanism of caffeine-induced insomnia through other pathways, such as adenosine. The results provide a reference for decoding neurochemicals involved in the development of the full cycle of mammalian life and the exploration of insomnia and even other mental diseases induced by exogenous substances in the future.


Asunto(s)
Drosophila melanogaster , Trastornos del Inicio y del Mantenimiento del Sueño , Animales , Cromatografía Liquida , Drosophila melanogaster/fisiología , Mamíferos , Sueño , Espectrometría de Masas en Tándem
9.
J Sep Sci ; 44(21): 3933-3958, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34473407

RESUMEN

Baihe Dihuang decoction is a commonly used herbal formula to treat depression and insomnia in traditional Chinese medicine. This study established a liquid chromatography-mass spectrometry method to investigate the potential active ingredients and the components absorbed in the blood and brain tissue of mice. Using a new data processing method, 94 chemical components were identified, 33 and 9 of which were absorbed in the blood and brain. More interestingly, we analyzed the substance changes during co-decoction and the characteristics of the compounds absorbed in the blood and brain. The results show that 71 newly generated chemical components were discovered from co-decoction: 38 with fragment information and five absorbed in the blood. Ultimately, the results of molecular docking show that these components have excellent performance in proteins of γ-aminobutyric acid, serotonin and melatonin receptors. The docking results of emodin with Monoamine Oxidase A and Melatonin Receptor 1A, and luteolin with Solute Carrier Family 6 Member 4, Glyoxalase I, Monoamine Oxidase B and Melatonin Receptor 1A, may explain the mechanism of action of Baihe Dihuang decoction in treating insomnia and depression. Overall, our research results may provide novel perspectives for further understanding of the effective substances in Baihe Dihuang decoction.


Asunto(s)
Cromatografía Liquida/métodos , Medicamentos Herbarios Chinos , Espectrometría de Masas/métodos , Animales , Medicamentos Herbarios Chinos/análisis , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/metabolismo , Masculino , Ratones , Ratones Endogámicos ICR , Simulación del Acoplamiento Molecular
10.
Prostate ; 80(8): 609-618, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32168400

RESUMEN

BACKGROUND: Using a functional analysis of prostate cancer cells, we found a CD24-dependent inactivation of mutant p53, but the clinical significance of this observation remained uncertain. Here, we validated these results with samples of human prostate cancer and explored the role of a CD24-p53 axis in racial disparities of prostate cancer. METHODS: Samples of formalin-fixed, paraffin-embedded prostate cancer from 141 European Americans (EAs) and 147 African Americans (AAs) in two independent sample cohorts were assessed for protein expression of CD24, mutant p53, mouse double minute 2 human homolog (MDM2), and cyclin dependent kinase inhibitor 2A (ARF) using immunohistochemical analyses. All samples were analyzed for TP53R175H and TP53R273H . RESULTS: CD24, mutant p53, MDM2, and ARF proteins were expressed in 55%, 24%, 39%, and 68% of prostate cancer samples, respectively. CD24 and mutant p53 were present more frequently in late-stage and metastatic prostate cancer. The presence of CD24 was associated with a greater than fourfold risk of metastasis, which included lymph node and distant metastases. H score analysis showed positive correlations of CD24 expression with mutant p53 (r = .308, P < .001) and MDM2 (r = .227, P = .004). There was a negative correlation for CD24 with ARF (r = -.280, P < .001). A racial disparity was evident for CD24 (AAs/EAs: 64% vs 47%; P = .004) but not for mutant p53 (AA/EA: 28% vs 21%; P = .152). In 32 CD24+ /mutant p53+ cases, a TP53R273H mutation was found in five cases, but no TP53R175H mutation was found. CONCLUSION: The CD24-p53 axis may contribute to aggressive and metastatic prostate cancers, especially those of AAs. This observation enhances understanding of the pathogenesis of prostate cancer and its associated racial disparities.


Asunto(s)
Negro o Afroamericano/genética , Antígeno CD24/genética , Neoplasias de la Próstata/genética , Proteína p53 Supresora de Tumor/genética , Adulto , Anciano , Antígeno CD24/biosíntesis , Antígeno CD24/metabolismo , Disparidades en el Estado de Salud , Humanos , Masculino , Persona de Mediana Edad , Mutación Missense , Metástasis de la Neoplasia , Estadificación de Neoplasias , Adhesión en Parafina , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Transducción de Señal , Fijación del Tejido , Proteína p53 Supresora de Tumor/biosíntesis , Proteína p53 Supresora de Tumor/metabolismo , Población Blanca/genética
11.
J Sep Sci ; 43(16): 3333-3348, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32496008

RESUMEN

In recent years, direct and indirect evidence has been found of the efficacy of the traditional Chinese medicine Bergenia purpurascens in treating arthritis and osteoarthritis. Several major components, such as bergenin and 11-O-galloylbergenin, have good anti-inflammatory activity. Since research on the chemical components of Bergenia purpurascens and related mechanisms for the treatment of osteoarthritis has never been performed, this study aimed to analyze the chemical components of Bergenia purpurascens through ultra high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry technology and the UNIFI screening platform to predict the underlying mechanisms in treating osteoarthritis by analyzing the network pharmacology. In total, 43 chemical constituents were identified, mainly flavonoids (18), phenolic glycosides (13), and organic acids (7). Among them, 16 components were found in Bergenia purpurascens for the first time. Through the analysis of network pharmacology, several potential candidate targets and pathways were initially predicted, including AKT1, MAPK1, and MAPK3, as well as the apoptosis, estrogen, and MAPK signaling pathways. Bergenin, 11-O-galloylbergenin, arbutin, catechin-3-O-gallate, and other components play a synergistic role in treating osteoarthritis. This study analyzed the chemical components of Bergenia purpurascens and preliminarily revealed potential mechanisms of treating osteoarthritis, providing a basis for further evaluating the drug's efficacy.


Asunto(s)
Antiinflamatorios/uso terapéutico , Medicamentos Herbarios Chinos/uso terapéutico , Osteoartritis/tratamiento farmacológico , Antiinflamatorios/química , Antiinflamatorios/aislamiento & purificación , Cromatografía Líquida de Alta Presión , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/aislamiento & purificación , Humanos , Espectrometría de Masas , Medicina Tradicional China , Simulación del Acoplamiento Molecular , Estructura Molecular , Osteoartritis/metabolismo , Factores de Tiempo
12.
Biomacromolecules ; 20(7): 2754-2762, 2019 07 08.
Artículo en Inglés | MEDLINE | ID: mdl-31125205

RESUMEN

Substantial adsorption of water vapor triggered by hydrogen-bonding interactions between water molecules and cellulose chains (or nanoplates) is hard to avoid in nanocomposite films, although the addition of nanoplates can improve the oxygen (or carbon dioxide) barrier property. In the present work, an effective strategy is raised to decline adsorption by weakening hydrogen-bonding interactions via chemical cross-linking by epichlorohydrin (ECH) without sacrificing the homogeneous dispersion of nanoplates. The generated microdomain structure of the chemical cross-linking reaction via ECH is explicitly revealed by micro-Raman imaging. Unambiguously, Raman maps of scanning elucidate the distribution and morphology of physical and chemical cross-linking domains quantitatively. The chemical cross-linking domains are nearly uniformly located in the matrix at a low degree of cross-linking, while the interconnected and assembled networks are formed at a high degree of cross-linking. ECH boosts the formation of chemical cross-linking microdomains, bringing out the terrific water vapor barrier property and alleviating the interfacial interactions in penetration, consequently magnifying the water contact angle and holding back the water vapor permeability. Our methodology confers an effective and convenient strategy to obtain remarkable water vapor-resistant cellulose-based films that meet the practical application in the packaging fields.


Asunto(s)
Celulosa/química , Epiclorhidrina/química , Nanocompuestos/química , Agua/química , Celulosa/farmacología , Reactivos de Enlaces Cruzados/química , Reactivos de Enlaces Cruzados/farmacología , Epiclorhidrina/farmacología , Enlace de Hidrógeno/efectos de los fármacos , Permeabilidad/efectos de los fármacos , Espectrometría Raman , Vapor
13.
Mol Cell ; 44(5): 770-84, 2011 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-22152480

RESUMEN

Both H4K16 acetylation and H3K4 trimethylation are required for gene activation. However, it is still largely unclear how these modifications are orchestrated by transcriptional factors. Here, we analyzed the mechanism of the transcriptional activation by FOXP3, an X-linked suppressor of autoimmune diseases and cancers. FOXP3 binds near transcriptional start sites of its target genes. By recruiting MOF and displacing histone H3K4 demethylase PLU-1, FOXP3 increases both H4K16 acetylation and H3K4 trimethylation at the FOXP3-associated chromatins of multiple FOXP3-activated genes. RNAi-mediated silencing of MOF reduced both gene activation and tumor suppression by FOXP3, while both somatic mutations in clinical cancer samples and targeted mutation of FOXP3 in mouse prostate epithelial cells disrupted nuclear localization of MOF. Our data demonstrate a pull-push model in which a single transcription factor orchestrates two epigenetic alterations necessary for gene activation and provide a mechanism for somatic inactivation of the FOXP3 protein function in cancer cells.


Asunto(s)
Factores de Transcripción Forkhead/metabolismo , Histona Acetiltransferasas/metabolismo , Histonas/metabolismo , Histona Demetilasas con Dominio de Jumonji/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Represoras/metabolismo , Acetilación , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Línea Celular Tumoral , Núcleo Celular/metabolismo , Femenino , Factores de Transcripción Forkhead/genética , Regulación de la Expresión Génica , Células HEK293 , Humanos , Metilación , Mutación
14.
Int J Mol Sci ; 19(7)2018 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-30011797

RESUMEN

Forkhead Box Protein P3 (FOXP3), a transcription factor of the FOX protein family, is essentially involved in the development of regulatory T (Treg) cells, and functions as a tumor suppressor. Although FOXP3 has been widely studied in immune system and cancer development, its function in the regulation of the UBC9 gene (for the sole E2 enzyme of SUMOylation) is unknown. Herein, we find that the overexpression of FOXP3 in human MCF7 breast cancer cells increases the level of UBC9 mRNA. Moreover, the level of UBC9 protein dose-dependently increases in the FOXP3-Tet-off MCF7 cells. Notably, the promoter activity of the UBC9 is activated by FOXP3 in a dose-dependent manner in both the MCF7 and HEK293 cells. Next, by mapping the UBC9 promoter as well as the site-directed mutagenesis and ChIP analysis, we show that the FOXP3 response element at the -310 bp region, but not the -2182 bp region, is mainly required for UBC9 activation by FOXP3. Finally, we demonstrate that the removal of phosphorylation (S418A and Y342F) and the removal of acetylation/ubiquitination (K263R and K263RK268R) of the FOXP3 result in attenuated transcriptional activity of UBC9. Taken together, FOXP3 acts as a novel transcriptional activator of the human UBC9 gene, suggesting that FOXP3 may have physiological functions as a novel player in global SUMOylation, as well as other post-translational modification systems.


Asunto(s)
Factores de Transcripción Forkhead/genética , Regulación Neoplásica de la Expresión Génica , Mutación , Elementos de Respuesta/genética , Enzimas Ubiquitina-Conjugadoras/genética , Acetilación , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Factores de Transcripción Forkhead/metabolismo , Células HEK293 , Humanos , Células MCF-7 , Fosforilación , Sumoilación , Enzimas Ubiquitina-Conjugadoras/metabolismo
15.
Molecules ; 23(12)2018 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-30545024

RESUMEN

The purpose of this study was to fabricate biopolymer conjugates from lactoferrin (LF) and hyaluronic acid (HA) and then to investigate their potential as emulsifiers for forming sesamol-loaded emulsions. Initially, LF-HA covalent conjugates were formed using the carbodiimide coupling method in aqueous solutions at pH = 4.5, and then the nature of the conjugates was investigated using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), Fourier Transform Infrared Spectroscopy (FTIR) spectroscopy, and fluorescence spectroscopy. The results demonstrated the formation of an amide link between the amine groups of LF and the carboxyl groups of HA. Sesamol emulsions were prepared using the LF-HA conjugates as emulsifiers and their stability was determined. The conjugates improved both the physical and chemical stability of the emulsions during storage. Optimum stability of the emulsion was obtained at a LF-to-HA molar ratio of 2:1. Our results suggest that LF-HA conjugates may be effective emulsifiers for use in food stuffs and other applications.


Asunto(s)
Benzodioxoles/química , Emulsiones/química , Ácido Hialurónico/química , Lactoferrina/química , Fenoles/química , Estabilidad de Medicamentos , Electroforesis en Gel de Poliacrilamida , Emulsionantes/química , Tamaño de la Partícula , Espectrometría de Fluorescencia , Espectroscopía Infrarroja por Transformada de Fourier
16.
Breast Cancer Res ; 19(1): 73, 2017 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-28637482

RESUMEN

BACKGROUND: Members of the microRNA (miR)-200 family, which are involved in tumor metastasis, have potential as cancer biomarkers, but their regulatory mechanisms remain elusive. METHODS: We investigated FOXP3-inducible breast cancer cells, Foxp3 heterozygous Scurfy mutant (Foxp3 sf/+ ) female mice, and patients with breast cancer for characterization of the formation and regulation of the miR-200 family in breast cancer cells and circulation. Participants (259), including patients with breast cancer or benign breast tumors, members of breast cancer families, and healthy controls, were assessed for tumor and circulating levels of the miR-200 family. RESULTS: First, we identified a FOXP3-KAT2B-miR-200c/141 axis in breast cancer cells. Second, aging Foxp3 sf/+ female mice developed spontaneous breast cancers and lung metastases. Levels of miR-200c and miR-141 were lower in Foxp3 sf/+ tumor cells than in normal breast epithelial cells, but plasma levels of miR-200c and miR-141 in the Foxp3 sf/+ mice increased during tumor progression and metastasis. Third, in patients with breast cancer, the levels of miR-200c and 141 were lower in FOXP3 low relative to those with FOXP3 high breast cancer cells, especially in late-stage and metastatic cancer cells. The levels of miR-200c and miR-141 were higher in plasma from patients with metastatic breast cancer than in plasma from those with localized breast cancer, with benign breast tumors, with a family history of breast cancer, or from healthy controls. Finally, in Foxp3 sf/+ mice, plasma miR-200c and miR-141 appeared to be released from tumor cells. CONCLUSIONS: miR-200c and miR-141 are regulated by a FOXP3-KAT2B axis in breast cancer cells, and circulating levels of miR-200c and miR-141 are potential biomarkers for early detection of breast cancer metastases.


Asunto(s)
Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Factores de Transcripción Forkhead/genética , Regulación Neoplásica de la Expresión Génica , MicroARNs/genética , Factores de Transcripción p300-CBP/genética , Adulto , Anciano , Animales , Biomarcadores de Tumor , Neoplasias de la Mama/metabolismo , Línea Celular Tumoral , MicroARN Circulante , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Femenino , Humanos , Ratones , Persona de Mediana Edad , Clasificación del Tumor , Metástasis de la Neoplasia , Estadificación de Neoplasias , Curva ROC , Transcripción Genética
17.
J Cell Sci ; 128(22): 4171-82, 2015 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-26446260

RESUMEN

The regulation and function of the crucial cell cycle regulator cyclin E (CycE) remains elusive. Unlike other cyclins, CycE can be uniquely controlled by mitochondrial energetics, the exact mechanism being unclear. Using mammalian cells (in vitro) and Drosophila (in vivo) model systems in parallel, we show that CycE can be directly regulated by mitochondria through its recruitment to the organelle. Active mitochondrial bioenergetics maintains a distinct mitochondrial pool of CycE (mtCycE) lacking a key phosphorylation required for its degradation. Loss of the mitochondrial fission protein dynamin-related protein 1 (Drp1, SwissProt O00429 in humans) augments mitochondrial respiration and elevates the mtCycE pool allowing CycE deregulation, cell cycle alterations and enrichment of stem cell markers. Such CycE deregulation after Drp1 loss attenuates cell proliferation in low-cell-density environments. However, in high-cell-density environments, elevated MEK-ERK signaling in the absence of Drp1 releases mtCycE to support escape of contact inhibition and maintain aberrant cell proliferation. Such Drp1-driven regulation of CycE recruitment to mitochondria might be a mechanism to modulate CycE degradation during normal developmental processes as well as in tumorigenic events.


Asunto(s)
Ciclina E/metabolismo , GTP Fosfohidrolasas/metabolismo , Proteínas Asociadas a Microtúbulos/metabolismo , Mitocondrias/metabolismo , Proteínas Mitocondriales/metabolismo , Animales , Ciclo Celular/fisiología , Proliferación Celular/fisiología , Ciclina E/genética , Drosophila melanogaster , Dinaminas , Femenino , GTP Fosfohidrolasas/genética , Humanos , Proteínas Asociadas a Microtúbulos/genética , Proteínas Mitocondriales/genética , Fosforilación , Transducción de Señal , Transfección
18.
Mol Carcinog ; 56(2): 641-650, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27377469

RESUMEN

CD24 plays an oncogenic role in the onset and progression of various human cancers, including prostate cancer. In the present study, we identified two linkage disequilibrium blocks with four recombination hotspot motifs in human CD24 locus. To elucidate whether genetic variants of CD24 are associated with susceptibility to prostate cancer and its disease status, we conducted a case-control association study with two P170 C/T and P-534 A/C polymorphisms of CD24 in 590 patients with prostate cancer and 590 healthy controls. A significant increased risk of prostate cancer was found in men with the P170T/T genotype over the P170C/C genotype (odd ratio = 1.74, 95% confidence interval = 1.16-2.63, P = 0.008), and in men with the P-534C/C genotype over the P-534A/A genotype (odd ratio = 1.47, 95% CI = 1.18-2.26, P = 0.003). Cochran-Armitage trend analysis showed that the P170T allele was significantly correlated with an increased risk of prostate cancer progression (P = 0.029, trend between genotypes and stages) and this observation was also validated in an independent sample cohort. Next, we found that tumors with P170T or P-534C alleles had more twofold increased protein expressions of CD24 as compared to those with P170C or P-534A alleles, respectively. Likewise, tumors with a combination of P170T/T and P-534C/C genotypes were associated with a high mRNA level of CD24. Our data suggest a significant association of CD24 genetic variants with prostate cancer onset and progression, which provides new insight into molecular genetics of prostate cancer; however, these findings need to be validated in multiple independent cohorts. © 2016 Wiley Periodicals, Inc.


Asunto(s)
Antígeno CD24/genética , Polimorfismo Genético , Próstata/patología , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/patología , Anciano , Anciano de 80 o más Años , Alelos , Antígeno CD24/análisis , Estudios de Casos y Controles , Progresión de la Enfermedad , Regulación Neoplásica de la Expresión Génica , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Desequilibrio de Ligamiento , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Polimorfismo de Longitud del Fragmento de Restricción , Polimorfismo de Nucleótido Simple
19.
Int J Mol Sci ; 18(2)2017 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-28146118

RESUMEN

Jun dimerization protein 2 (JDP2), a basic leucine zipper transcription factor, is involved in numerous biological and cellular processes such as cancer development and regulation, cell-cycle regulation, skeletal muscle and osteoclast differentiation, progesterone receptor signaling, and antibacterial immunity. Though JDP2 is widely expressed in mammalian tissues, its function in gonads and adrenals (such as regulation of steroidogenesis and adrenal development) is largely unknown. Herein, we find that JDP2 mRNA and proteins are expressed in mouse adrenal gland tissues. Moreover, overexpression of JDP2 in Y1 mouse adrenocortical cancer cells increases the level of melanocortin 2 receptor (MC2R) protein. Notably, Mc2r promoter activity is activated by JDP2 in a dose-dependent manner. Next, by mapping the Mc2r promoter, we show that cAMP response elements (between -1320 and -720-bp) are mainly required for Mc2r activation by JDP2 and demonstrate that -830-bp is the major JDP2 binding site by real-time chromatin immunoprecipitation (ChIP) analysis. Mutations of cAMP response elements on Mc2r promoter disrupts JDP2 effect. Furthermore, we demonstrate that removal of phosphorylation of JDP2 results in attenuated transcriptional activity of Mc2r. Finally, we show that JDP2 is a candidate for SUMOylation and SUMOylation affects JDP2-mediated Mc2r transcriptional activity. Taken together, JDP2 acts as a novel transcriptional activator of the mouse Mc2r gene, suggesting that JDP2 may have physiological functions as a novel player in MC2R-mediated steroidogenesis as well as cell signaling in adrenal glands.


Asunto(s)
Proteínas de la Membrana/metabolismo , Proteínas Represoras/metabolismo , Activación Transcripcional , Glándulas Suprarrenales , Animales , Expresión Génica , Proteínas de la Membrana/genética , Ratones , Fosforilación , Regiones Promotoras Genéticas , Unión Proteica , Proteínas Represoras/genética , Sumoilación
20.
J Cell Biochem ; 117(2): 426-38, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26212494

RESUMEN

Transcription factor forkhead box protein P2 (FOXP2) plays an essential role in the development of language and speech. However, the transcriptional activity of FOXP2 regulated by the post-translational modifications remains unknown. Here, we demonstrated that FOXP2 is clearly defined as a SUMO target protein at the cellular levels as FOXP2 is covalently modified by both SUMO1 and SUMO3. Furthermore, SUMOylation of FOXP2 was significantly decreased by SENP2 (a specific SUMOylation protease). We further showed that FOXP2 is selectively SUMOylated in vivo on a phylogenetically conserved lysine 674 but the SUMOylation does not alter subcellular localization and stability of FOXP2. Interestingly, we observed that human etiological FOXP2 R553H mutation robustly reduces its SUMOylation potential as compared to wild-type FOXP2. In addition, the acidic residues downstream the core SUMO motif on FOXP2 are required for its full SUMOylation capacity. Finally, our functional analysis using reporter gene assays showed that SUMOylation may modulate transcriptional activity of FOXP2 in regulating downstream target genes (DISC1, SRPX2, and MiR200c). Altogether, we provide the first evidence that FOXP2 is a substrate for SUMOylation and SUMOylation of FOXP2 plays a functional role in regulating its transcriptional activity.


Asunto(s)
Factores de Transcripción Forkhead/metabolismo , Sumoilación , Secuencia de Aminoácidos , Sustitución de Aminoácidos , Secuencia de Consenso , Factores de Transcripción Forkhead/química , Células HEK293 , Humanos , Células MCF-7 , Datos de Secuencia Molecular , Mutación Puntual , Estabilidad Proteica , Proteína SUMO-1/metabolismo , Activación Transcripcional
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