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1.
Biosens Bioelectron ; 224: 115033, 2023 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-36621082

RESUMEN

Staphylococcus aureus is one of the most prevalent threats to public health. Rapid detection with high sensitivity and targeted killing is crucial to curb its spread. Herein, a metal-bearing nanocomposite, consisting of a bimetallic nanoparticle and a metal-organic framework (Au/Ir@Cu/Zn-MOF) was constructed. Upon conjugation with anti-S. aureus antibody, this nanocomposite (Ab-Au/Ir@Cu/Zn-MOF) was exploited for its dual functions, i.e. as a reporting probe in a lateral flow immunoassay and a high efficiency antibacterial reagent. Benefiting from the enrichment of Au/Ir NPs by the Cu/Zn-MOF, the Au/Ir@Cu/Zn-MOF-based lateral flow immunoassay sensor exhibited a visual limit of detection of 103 CFU/mL, which was100 times more sensitive than Au/Ir-based sensor. Moreover, the Ab-Au/Ir@Cu/Zn-MOF probe possessed synergistic photothermal-chemodynamic bactericidal effect that specifically targeted against S. aureus. Under a co-treatment by H2O2 (0.4 mM) and 808 nm near infrared irradiation (1 W/cm2, 5 min), complete sterilization of 5 × 105-106 CFU/mL S. aureus was achieved at a nanocomposite concentration as low as 6.25 µg/mL. The superior antibacterial efficiency was attributable to the three-fold properties of the Ab-Au/Ir@Cu/Zn-MOF probe: (1) enhanced multi-enzyme mimicking activities that promote reactive oxygen species generation, (2) high photothermal activity (efficiency of 53.70%), and (3) bacteria targeting ability via the antibody coating. By changing the antibody, this nanocomposite can be tailored to target a wide range of bacteria species, for detection and for precise antibacterial treatment.


Asunto(s)
Técnicas Biosensibles , Inmunoconjugados , Nanopartículas del Metal , Peróxido de Hidrógeno , Bacterias , Anticuerpos , Antibacterianos/farmacología , Inmunoensayo , Staphylococcus aureus , Zinc
2.
Anal Methods ; 14(11): 1124-1133, 2022 03 17.
Artículo en Inglés | MEDLINE | ID: mdl-35212322

RESUMEN

Infections from invasive Listeria monocytogenes (L. monocytogenes) frequently occur in food and can cause high morbidity and death. Thus, the sensitive, specific, and rapid detection of L. monocytogenes is critical for ensuring food safety and public health. Herein, a fluorescence immunoassay for trace L. monocytogenes detection was designed based on guinea pig antibody-functionalized magnetic nanoparticles (Fe3O4 NPs/pAb1) and rabbit antibody-anchored CdZnTe quantum dots (CdZnTe QDs/pAb2). Because of the antibody-directed magnetic separation and long-wave fluorescent emission for CdZnTe QD indication, the constructed immunoassay strategy presented excellent anti-interference performance toward a biological matrix. The immunosensor exhibited a wide detection range of 1 to 109 CFU mL-1 for L. monocytogenes and a low limit of detection (LOD) of 1 CFU mL-1, achieving an exceptionally sensitive detection of trace L. monocytogenes. Meanwhile, the immunosensor showed good specificity and had a short time-consumption of 60 min to realize the accurate determination of trace Listeria monocytogenes in spiked tap water and pasteurized milk samples.


Asunto(s)
Técnicas Biosensibles , Listeria monocytogenes , Puntos Cuánticos , Animales , Cadmio , Microbiología de Alimentos , Cobayas , Inmunoensayo , Separación Inmunomagnética , Conejos , Telurio , Zinc
3.
Nat Commun ; 12(1): 6407, 2021 11 04.
Artículo en Inglés | MEDLINE | ID: mdl-34737287

RESUMEN

Colorectal cancer is one of the most common cancers in the world. Although genomic mutations and single nucleotide polymorphisms have been extensively studied, the epigenomic status in colorectal cancer patient tissues remains elusive. Here, together with genomic and transcriptomic analysis, we use ChIP-Seq to profile active enhancers at the genome wide level in colorectal cancer paired patient tissues (tumor and adjacent tissues from the same patients). In total, we sequence 73 pairs of colorectal cancer tissues and generate 147 H3K27ac ChIP-Seq, 144 RNA-Seq, 147 whole genome sequencing and 86 H3K4me3 ChIP-Seq samples. Our analysis identifies 5590 gain and 1100 lost variant enhancer loci in colorectal cancer, and 334 gain and 121 lost variant super enhancer loci. Multiple key transcription factors in colorectal cancer are predicted with motif analysis and core regulatory circuitry analysis. Further experiments verify the function of the super enhancers governing PHF19 and TBC1D16 in regulating colorectal cancer tumorigenesis, and KLF3 is identified as an oncogenic transcription factor in colorectal cancer. Taken together, our work provides an important epigenomic resource and functional factors for epigenetic studies in colorectal cancer.


Asunto(s)
Neoplasias Colorrectales/genética , Animales , Línea Celular , Secuenciación de Inmunoprecipitación de Cromatina , Epigenómica , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica/genética , Regulación Neoplásica de la Expresión Génica/fisiología , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Análisis de Secuencia de ARN
4.
Front Mol Biosci ; 8: 701531, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34409068

RESUMEN

Head and neck squamous cell carcinoma (HNSCC) is one of the most common cancers in the world, but its epigenomic features have not been determined. Here, we studied the chromatin landscape of active enhancers of HNSCC head tumor tissues by performing H3K27ac and H3K4me1 ChIP-Seq with a Tgfbr1/Pten double conditional knockout HNSCC mouse model. We identified 1,248 gain variant enhancer loci (VELs) and 2,188 lost VELs, as well as 153 gain variant super enhancer loci (VSELs) and 234 lost VSELs. Potentially involved transcription factors were predicted with motif analysis, and we identified AP-1 as one of the critical oncogenic transcription factors in HNSCC and many other types of cancer. Combining transcriptomic and epigenomic data, our analysis also showed that AP-1 and histone modifications coordinately regulate target gene expression in HNSCC. In conclusion, our study provides important epigenomic information for enhancer studies in HNSCC and reveals new mechanism for AP-1 regulating HNSCC.

5.
Adv Sci (Weinh) ; 8(19): e2100779, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34363353

RESUMEN

In eukaryote cells, core components of chromatin, such as histones and DNA, are packaged in nucleus. Leakage of nuclear materials into cytosol will induce pathological effects. However, the underlying mechanisms remain elusive. Here, cytoplasmic localization of nuclear materials induced by chromatin dysregulation (CLIC) in mammalian cells is reported. H3K9me3 inhibition by small chemicals, HP1α knockdown, or knockout of H3K9 methylase SETDB1, induces formation of cytoplasmic puncta containing histones H3.1, H4 and cytosolic DNA, which in turn activates inflammatory genes and autophagic degradation. Autophagy deficiency rescues H3 degradation, and enhances the activation of inflammatory genes. MRE11, a subunit of MRN complex, enters cytoplasm after heterochromatin dysregulation. Deficiency of MRE11 or NBS1, but not RAD50, inhibits CLIC puncta in cytosol. MRE11 depletion represses tumor growth enhanced by HP1α deficiency, suggesting a connection between CLIC and tumorigenesis. This study reveals a novel pathway that heterochromatin dysregulation induces translocation of nuclear materials into cytoplasm, which is important for inflammatory diseases and cancer.


Asunto(s)
Citoplasma/genética , Citoplasma/metabolismo , Epigénesis Genética/genética , Histonas/genética , Histonas/metabolismo , Animales , Masculino , Ratones , Ratones Endogámicos BALB C , Modelos Animales , Factores de Transcripción/genética
6.
ACS Appl Mater Interfaces ; 13(18): 21680-21692, 2021 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-33934598

RESUMEN

Herein, a Au-Au/IrO2 nanocomposite with tandem enzyme-mimicking activity was innovatively synthesized, which can show outstanding glucose oxidase (GOx)-like activity and peroxidase-like activity simultaneously under neutral conditions. Moreover, a Au-Au/IrO2@Cu(PABA) reactor was prepared via encapsulation of the Au-Au/IrO2 nanocomposite in a Cu(PABA) metal organic framework. The reactor not only exhibits excellent organic solvent stability, acid resistance, and reusability but also displays better cascade reaction catalytic efficiency (kcat/Km = 148.86 min-1 mM-1) than the natural free enzyme system (GOx/HRP) (kcat/Km = 98.20 min-1 mM-1) and Au-Au/IrO2 nanocomposite (kcat/Km = 135.24 min-1 mM-1). In addition, it is found that the reactor can catalyze glucose or dissolved oxygen to produce active oxygen species (ROS) including HO, 1O2, and O2-· through its enzyme-mimicking activity. Finally, the novel reactor was successfully used in organic dye degradation and antibacterial application. The results show that it can effectively degrade methyl orange, methylene blue, and rhodamine B, which all can reach a degradation rate of nearly 100% after interacting with Au-Au/IrO2@Cu (PABA) for 3.5 h. Furthermore, the reactor also exhibits excellent antibacterial activity, so as to achieve a complete bactericidal effect to Staphylococcus aureus and Escherichia coli at a concentration of 12.5 µg mL-1.


Asunto(s)
Antibacterianos/farmacología , Colorantes/química , Complejos de Coordinación/química , Enzimas/química , Estructuras Metalorgánicas/química , Metales/química , Catálisis , Escherichia coli/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Staphylococcus aureus/efectos de los fármacos
7.
Infect Dis Poverty ; 10(1): 40, 2021 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-33766145

RESUMEN

BACKGROUND: Dengue fever (DF) is a mosquito-borne infectious disease that has threatened tropical and subtropical regions in recent decades. An early and targeted warning of a dengue epidemic is important for vector control. Current studies have primarily determined weather conditions to be the main factor for dengue forecasting, thereby neglecting that environmental suitability for mosquito breeding is also an important factor, especially in fine-grained intra-urban settings. Considering that street-view images are promising for depicting physical environments, this study proposes a framework for facilitating fine-grained intra-urban dengue forecasting by integrating the urban environments measured from street-view images. METHODS: The dengue epidemic that occurred in 167 townships of Guangzhou City, China, between 2015 and 2019 was taken as a study case. First, feature vectors of street-view images acquired inside each township were extracted by a pre-trained convolutional neural network, and then aggregated as an environmental feature vector of the township. Thus, townships with similar physical settings would exhibit similar environmental features. Second, the environmental feature vector is combined with commonly used features (e.g., temperature, rainfall, and past case count) as inputs to machine-learning models for weekly dengue forecasting. RESULTS: The performance of machine-learning forecasting models (i.e., MLP and SVM) integrated with and without environmental features were compared. This indicates that models integrating environmental features can identify high-risk urban units across the city more precisely than those using common features alone. In addition, the top 30% of high-risk townships predicted by our proposed methods can capture approximately 50-60% of dengue cases across the city. CONCLUSIONS: Incorporating local environments measured from street view images is effective in facilitating fine-grained intra-urban dengue forecasting, which is beneficial for conducting spatially precise dengue prevention and control.


Asunto(s)
Dengue , Animales , Ciudades , Dengue/epidemiología , Predicción , Mosquitos Vectores , Tiempo (Meteorología)
8.
Hepatology ; 73(5): 1797-1815, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33058300

RESUMEN

BACKGROUND AND AIMS: Trimethylation of Lys36 on histone 3 (H3K36me3) catalyzed by histone methyltransferase SET domain-containing 2 (SETD2) is one of the most conserved epigenetic marks from yeast to mammals. SETD2 is frequently mutated in multiple cancers and acts as a tumor suppressor. APPROACH AND RESULTS: Here, using a liver-specific Setd2 depletion model, we found that Setd2 deficiency is sufficient to trigger spontaneous HCC. Meanwhile, Setd2 depletion significantly increased tumor and tumor size of a diethylnitrosamine-induced HCC model. The mechanistic study showed that Setd2 suppresses HCC not only through modulating DNA damage response, but also by regulating lipid metabolism in the liver. Setd2 deficiency down-regulated H3K36me3 enrichment and expression of cholesterol efflux genes and caused lipid accumulation. High-fat diet enhanced lipid accumulation and promoted the development of HCC in Setd2-deficient mice. Chromatin immunoprecipitation sequencing analysis further revealed that Setd2 depletion induced c-Jun/activator protein 1 (AP-1) activation in the liver, which was trigged by accumulated lipid. c-Jun acts as an oncogene in HCC and functions through inhibiting p53 in Setd2-deficient cells. CONCLUSIONS: We revealed the roles of Setd2 in HCC and the underlying mechanisms in regulating cholesterol homeostasis and c-Jun/AP-1 signaling.


Asunto(s)
Carcinoma Hepatocelular/etiología , N-Metiltransferasa de Histona-Lisina/deficiencia , Metabolismo de los Lípidos , Neoplasias Hepáticas/etiología , Hígado/metabolismo , Alanina Transaminasa/sangre , Animales , Aspartato Aminotransferasas/sangre , Proteína 9 Asociada a CRISPR , Sistemas CRISPR-Cas , Carcinoma Hepatocelular/metabolismo , Línea Celular Tumoral , Colesterol/sangre , Inmunoprecipitación de Cromatina , Edición Génica , Regulación Neoplásica de la Expresión Génica , Células HEK293 , Células Hep G2 , N-Metiltransferasa de Histona-Lisina/metabolismo , Humanos , Neoplasias Hepáticas/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Triglicéridos/sangre
9.
J Pharm Sci ; 110(4): 1718-1726, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33160976

RESUMEN

The solid-state diversity of active pharmaceutical ingredients can provide theoretical guidance for the production and storage of drugs. In this study, three solid forms of glipizide were obtained through various methods, and the solid-state transformations were extensively investigated. Form I could be prepared using evaporative crystallization, cooling crystallization, anti-solvent crystallization, and solvent-mediated slurry conversion experiments (SSCE). Form II was produced by milling. Form III was obtained by milling and SSCE. The results of solid-state transformations indicated that Form I transformed to II during neat milling at 25 °C. In contrast, solvent inhibited the solid-state transformations of Form I under liquid-assisted milling. Forms II and III remained invariable under neat milling at 25 °C, and solid-state transformation of Form III also did not occur in the liquid-assisted milling. In SSCE, the solvent's nature and its temperature significantly influenced the solid-state conversion of amorphous glipizide. Form II converted to either Form I or III in water above 50 °C, and only transformed into Form I at 25 °C. However, the solid-state transformation did not occur when pure Form I or III was stirred in water. Form II also converted to Form I in the organic solvents SSCE at different temperatures.


Asunto(s)
Glipizida , Agua , Rastreo Diferencial de Calorimetría , Cristalización , Estabilidad de Medicamentos , Temperatura
10.
Mikrochim Acta ; 187(12): 675, 2020 11 25.
Artículo en Inglés | MEDLINE | ID: mdl-33241461

RESUMEN

A highly sensitive colorimetric sensing strategy based on enzyme@metal-organic framework (GAA@Cu-MOF) and IrO2/MnO2 nanocomposite was exploited innovatively for screening of α-glucosidase (GAA) inhibitors. IrO2/MnO2 nanocomposite exhibits excellent oxidase-mimicking activity which can directly catalyze the oxidation of 3,3,5,5,-tetramethylbenzidine (TMB) into a blue product with an absorption maximum at 652 nm. And GAA@Cu-MOF can decompose L-ascorbic acid-2-O-α-D-glucopyranosyl (AAG) to ascorbic acid (AA). The produced AA can destroy the IrO2/MnO2 nanocomposite and reduce its oxidase-like activity. However, the generation of AA is restricted when GAA inhibitors are added to the system, which allows the oxidase-like activity of the IrO2/MnO2 nanocomposite to be maintained. In view of this, a method for screening of GAA inhibitors was developed. In addition to enhancing the stability of GAA, the method can also effectively avoid the potential interference of H2O2 in the screening process of GAA inhibitors, which helps to improve the sensitivity of the method. Therefore, highly sensitive determination for acarbose and ascorbic acid are achieved with detection limits of 6.27 nM and 1.23 µM, respectively. The proposed method was successfully applied to screen potential GAA inhibitors from oleanolic acid derivatives. Graphical abstract.


Asunto(s)
Colorimetría/métodos , Inhibidores de Glicósido Hidrolasas/análisis , Estructuras Metalorgánicas/química , Nanocompuestos/química , alfa-Glucosidasas/metabolismo , Acarbosa/análisis , Ácido Ascórbico/análisis , Catálisis , Enzimas Inmovilizadas/química , Enzimas Inmovilizadas/metabolismo , Iridio/química , Límite de Detección , Compuestos de Manganeso/química , Óxidos/química , alfa-Glucosidasas/química
11.
Oncogenesis ; 9(5): 57, 2020 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-32483180

RESUMEN

Gene transcription is coordinately regulated by multiple transcription factors. However, a systematic approach is still lacking to identify co-regulators for transcription factors. Here, we performed ChIP-Seq analysis and predicted the regulators for p53-mediated transcription process, from which we confirmed the roles of GLIS2, MAZ and MEF2A in regulating p53 target genes. We revealed that GLIS2 selectively regulates the transcription of PUMA but not p21. GLIS2 deficiency caused the elevation of H3K27ac and p53 binding on the PUMA enhancer, and promoted PUMA expression. It increased the rate of apoptosis, but not cell cycle. Moreover, GLIS2 represses H3K27ac level on enhancers, regulates the gene expression related with focal adhesion and promotes cell migration, through inhibiting p300. Big data analysis supports GLIS2 as an oncogene in colon cancer, and perhaps other cancers. Taken together, we have predicted candidates for p53 transcriptional regulators, and provided evidence for GLIS2 as an oncogene through repressing enhancer activation.

12.
Proc Natl Acad Sci U S A ; 116(21): 10447-10452, 2019 05 21.
Artículo en Inglés | MEDLINE | ID: mdl-31061131

RESUMEN

STAT3 is a transcription factor that plays central roles in various physiological processes, including differentiation of Th cells. Its deregulation results in serious diseases, including inflammatory diseases and cancer. The mechanisms related to how STAT3 activity is regulated remain enigmatic. Here we show that overexpression of FAM64A potentiates IL-6-induced activation of STAT3 and expression of downstream target genes, whereas deficiency of FAM64A has the opposite effects. FAM64A interacts with STAT3 in the nucleus and regulates binding of STAT3 to the promoters of its target genes. Deficiency of Fam64a significantly impairs differentiation of Th17 but not Th1 or induced regulatory T cells (iTreg). In addition, Fam64a deficiency attenuates experimental autoimmune encephalomyelitis (EAE) and dextran sulfate sodium (DSS)-induced colitis, which is correlated with decreased differentiation of Th17 cells and production of proinflammatory cytokines. Furthermore, Fam64a deficiency suppresses azoxymethane (AOM)/DSS-induced colitis-associated cancer (CAC) in mice. These findings suggest that FAM64A regulates Th17 differentiation and colitis and inflammation-associated cancer by modulating transcriptional activity of STAT3.


Asunto(s)
Carcinogénesis/metabolismo , Colitis/metabolismo , Factor de Transcripción STAT3/metabolismo , Células Th17 , Animales , Diferenciación Celular , Colitis/complicaciones , Modelos Animales de Enfermedad , Femenino , Regulación de la Expresión Génica , Ratones
13.
Clin Epigenetics ; 11(1): 48, 2019 03 12.
Artículo en Inglés | MEDLINE | ID: mdl-30867030

RESUMEN

BACKGROUND: Activation of transcription enhancers, especially super-enhancers, is one of the critical epigenetic features of tumorigenesis. However, very few studies have systematically identified the enhancers specific in cancer tissues. METHODS: Here, we studied the change of histone modifications in MMTV-PyVT breast cancer model, combining mass spectrometry-based proteomics and ChIP-seq-based epigenomics approaches. Some of the proteomic results were confirmed with western blotting and IHC staining. An inhibitor of H3K27ac was applied to study its effect on cancer development. RESULTS: H3K27ac and H4K8ac are elevated in cancer, which was confirmed in patient tissue chips. ChIP-seq revealed that H4K8ac is co-localized with H3K27ac on chromatin, especially on distal enhancers. Epigenomic studies further identified a subgroup of super-enhancers marked by H3K4me3 peaks in the intergenic regions. The H3K4me3-enriched regions enhancers are associated with higher level of H3K27ac and H4K8ac compared with the average level of conventional super-enhancers and are associated with higher transcription level of their adjacent genes. We identified 148 H3K4me3-enriched super-enhancers with higher gene expression in tumor, which may be critical for breast cancer. One inhibitor for p300 and H3K27ac, C646, repressed tumor formation probably through inhibiting Vegfa and other genes. CONCLUSIONS: Taken together, our work identifies novel regulators and provides important resource to the genome-wide enhancer studies in breast cancer and raises the possibility of cancer treatment through modulating enhancer activity.


Asunto(s)
Neoplasias de la Mama/patología , Elementos de Facilitación Genéticos , Histonas/genética , Histonas/metabolismo , Neoplasias Mamarias Experimentales/patología , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Secuenciación de Inmunoprecipitación de Cromatina , Epigénesis Genética , Epigenómica , Femenino , Regulación Neoplásica de la Expresión Génica , Redes Reguladoras de Genes , Código de Histonas , Humanos , Neoplasias Mamarias Experimentales/genética , Neoplasias Mamarias Experimentales/metabolismo , Proteómica , Activación Transcripcional , Regulación hacia Arriba
14.
Nucleic Acids Res ; 47(5): 2349-2364, 2019 03 18.
Artículo en Inglés | MEDLINE | ID: mdl-30649550

RESUMEN

Hippo pathway is involved in tumorigenesis, and its regulation in cytosol has been extensively studied, but its regulatory mechanisms in the nuclear are not clear. In the current study, using a FBS-inducing model following serum starvation, we identified KDM3A, a demethylase of histone H3K9me1/2, as a positive regulator for hippo target genes. KDM3A promotes gene expression through two mechanisms, one is to upregulate YAP1 expression, and the other is to facilitate H3K27ac on the enhancers of hippo target genes. H3K27ac upregulation is more relevant with gene activation, but not H3K4me3; and KDM3A depletion caused H3K9me2 upregulation mainly on TEAD1-binding enhancers rather than gene bodies, further resulting in H3K27ac decrease, less TEAD1 binding on enhancers and impaired transcription. Moreover, KDM3A is associated with p300 and required for p300 recruitment to enhancers. KDM3A deficiency delayed cancer cell growth and migration, which was rescued by YAP1 expression. KDM3A expression is correlated with YAP1 and hippo target genes in colorectal cancer patient tissues, and may serve as a potential prognosis mark. Taken together, our study reveals novel mechanisms for hippo signaling and enhancer activation, which is critical for tumorigenesis of colorectal cancer.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/genética , Neoplasias Colorrectales/genética , Histona Demetilasas con Dominio de Jumonji/genética , Fosfoproteínas/genética , Proteínas Serina-Treonina Quinasas/genética , Carcinogénesis/genética , Línea Celular Tumoral , Neoplasias Colorrectales/patología , Proteínas de Unión al ADN/genética , Elementos de Facilitación Genéticos/genética , Epigénesis Genética , Regulación Neoplásica de la Expresión Génica , Vía de Señalización Hippo , N-Metiltransferasa de Histona-Lisina/genética , Humanos , Proteínas Nucleares/genética , Pronóstico , Regiones Promotoras Genéticas/genética , Transducción de Señal , Factores de Transcripción de Dominio TEA , Factores de Transcripción/genética , Proteínas Señalizadoras YAP
15.
ACS Appl Mater Interfaces ; 10(35): 29314-29324, 2018 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-30091897

RESUMEN

A smart supramolecular nanosystem integrating targeting, chemotherapy, and photothermal therapy was constructed based on carboxylatopillar[5]arene (CP[5]A)-functionalized CuS nanoparticles (CuS@CP NPs). CuS@CP NPs with good monodispersibility and strong near-infrared absorption were synthesized in aqueous solution through a facile one-pot supramolecular capping method, followed by surface installation of a liver cancer-targeted galactose derivative through host-guest binding interaction. The resulting smart supramolecular nanosystem, namely, CuS@CPG, exhibited excellent photothermal ablation capability to HepG2 cells upon irradiation with laser at 808 nm. Chemotherapeutic drug, doxorubicin hydrochloride (DOX), was further loaded on CuS@CPG via electrostatic interactions between positively charged DOX and negatively charged CP[5]A to give CuS@CPG-DOX with a high drug-loading capacity up to 48.4%. The weakening of DOX-CP[5]A interactions in an acidic environment promoted the pH-responsive drug release from CuS@CPG-DOX. Significantly, this multifunctional supramolecular nanosystem showed a remarkably enhanced therapeutic effect through the combination of targeted chemotherapy and photothermal therapy upon in vitro cell study. Moreover, preliminary in vivo study demonstrated that CuS@CPG and CuS@CPG-DOX had good biocompatibility and excellent tumor inhibition effects upon near-infrared laser irradiation.


Asunto(s)
Cobre/clasificación , Quimioterapia , Nanopartículas/química , Fototerapia , Compuestos de Amonio Cuaternario/química , Doxorrubicina/administración & dosificación , Doxorrubicina/química , Liberación de Fármacos
16.
Biochim Biophys Acta Mol Cell Res ; 1865(7): 970-980, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29655804

RESUMEN

ERAD is an important process of protein quality control that eliminates misfolded or unassembled proteins from ER. Before undergoing proteasome degradation, the misfolded proteins are dislocated from ER membrane into cytosol, which requires the AAA ATPase p97/VCP and its cofactor, the NPL4-UFD1 dimer. Here, we performed a CRISPR-based screen and identify many candidates for ERAD regulation. We further confirmed four proteins, FBOX2, TRIM6, UFL1 and WDR20, are novel regulators for ERAD. Then the molecular mechanism for WDR20 in ERAD is further characterized. Depletion of WDR20 inhibits the degradation of TCRα, a typical ERAD substrate, while WDR20 overexpression reduces TCRα protein level. WDR20 associates with TCRα and central regulators of the ERAD system, p97, GP78 and HRD1. A portion of WDR20 localizes to the ER-containing microsomal membrane. WDR20 expression increases TCRα ubiquitination, and HRD1 E3 ligase is essential for the process. WDR20 seems to serve as an adaptor protein to mediate the interaction between p97 and TCRα. Our study provides novel candidates and reveals an unexpected role of WDR20 in ERAD regulation.


Asunto(s)
Proteínas Portadoras/genética , Proteínas Portadoras/metabolismo , Degradación Asociada con el Retículo Endoplásmico , Adenosina Trifosfatasas/metabolismo , Sistemas CRISPR-Cas , Proteínas Portadoras/química , Línea Celular Tumoral , Células HEK293 , Humanos , Microsomas/metabolismo , Proteínas Nucleares/metabolismo , Complejo de la Endopetidasa Proteasomal/metabolismo , Receptores de Antígenos de Linfocitos T alfa-beta/metabolismo , Ubiquitinación
17.
ACS Appl Mater Interfaces ; 10(15): 12155-12163, 2018 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-29261277

RESUMEN

A novel multifunctional drug delivery system has been constructed by assembling per-6-thio-ß-cyclodextrin-modified ultrasmall CuS nanoparticles (CD-CuS) onto fluorescent AIEgen-containing mesoporous silica nanoparticles (FMSN). The CD-CuS nanoparticles are anchored on the surface of benzimidazole-grafted FMSN, acting as a gatekeeper and photothermal agent. The prepared blue-emitting nanocomposite (FMSN@CuS) exhibits good biocompatibility and cell imaging capability. Anticancer drug doxorubicin hydrochloride (DOX) molecules are loaded into FMSN@CuS, and zero prerelease at physiological pH (7.4) and on-demand drug release at an acidic environment can be achieved due to the pH-responsive gate-opening of CD-CuS only at an acidic condition. The FMSN@CuS nanocomposite can generate obvious thermal effect after the exposure of 808 nm laser, which can also accelerate the DOX release. Meanwhile, the fluorescence intensity of DOX-loaded FMSN@CuS increases with the release of DOX, and the intracellular drug release process can be tracked according to the change of luminescence intensity. More importantly, DOX-loaded FMSN@CuS displays efficient anticancer effects in vitro upon 808 nm laser irradiation, demonstrating a good synergistic therapeutic effect via combining enhanced chemotherapy and photothermal therapy.


Asunto(s)
Dióxido de Silicio/química , Cobre , Ciclodextrinas , Doxorrubicina , Humanos , Hipertermia Inducida , Nanopartículas , Neoplasias , Fototerapia
18.
Epigenomics ; 9(8): 1077-1092, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28762778

RESUMEN

AIM: Epigenetic marks are critical regulators of chromatin and gene activity. Their roles in normal physiology and disease states, including cancer development, still remain elusive. Herein, the epigenomic change of H3K9me3, as well as its potential impacts on gene activity and genome stability, was investigated in an in vitro breast cancer transformation model. METHODS: The global H3K9me3 level was studied with western blotting. The distribution of H3K9me3 on chromatin and gene expression was studied with ChIP-Seq and RNA-Seq, respectively. RESULTS: The global H3K9me3 level decreases during transformation and its distribution on chromatin is reprogrammed. By combining with TCGA data, we identified 67 candidate oncogenes, among which five genes are totally novel. Our analysis further links H3K9me3 with transposon activity, and suggests H3K9me3 reduction increases the cell's sensitivity to DNA damage reagents. CONCLUSION: H3K9me3 reduction is possibly related with breast cancer transformation by regulating gene expression and chromatin stability during transformation.


Asunto(s)
Neoplasias de la Mama/genética , Transformación Celular Neoplásica/genética , Epigénesis Genética , Regulación Neoplásica de la Expresión Génica , Código de Histonas , Histonas/metabolismo , Neoplasias de la Mama/patología , Línea Celular Tumoral , Transformación Celular Neoplásica/patología , Células Cultivadas , Cromatina/genética , Cromatina/metabolismo , Femenino , Humanos , Oncogenes
19.
J Immunol ; 198(3): 1274-1284, 2017 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-28011935

RESUMEN

Upon virus infection, host cells use retinoic-acid-inducible geneI I (RIG-I)-like receptors to recognize viral RNA and activate type I IFN expression. To investigate the role of protein methylation in the antiviral signaling pathway, we screened all the SET domain-containing proteins and identified TTLL12 as a negative regulator of RIG-I signaling. TTLL12 contains SET and TTL domains, which are predicted to have lysine methyltransferase and tubulin tyrosine ligase activities, respectively. Exogenous expression of TTLL12 represses IFN-ß expression induced by Sendai virus. TTLL12 deficiency by RNA interference and CRISPR-gRNA techniques increases the induced IFN-ß expression and inhibits virus replication in the cell. The global gene expression profiling indicated that TTLL12 specifically inhibits the expression of the downstream genes of innate immunity pathways. Cell fractionation and fluorescent staining indicated that TTLL12 is localized in the cytosol. The mutagenesis study suggested that TTLL12's ability to repress the RIG-I pathway is probably not dependent on protein modifications. Instead, TTLL12 directly interacts with virus-induced signaling adaptor (VISA), TBK1, and IKKε, and inhibits the interactions of VISA with other signaling molecules. Taken together, our findings demonstrate TTLL12 as a negative regulator of RNA-virus-induced type I IFN expression by inhibiting the interaction of VISA with other proteins.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/fisiología , Proteínas Portadoras/fisiología , Interferón Tipo I/fisiología , Transducción de Señal/fisiología , Proteínas Portadoras/análisis , Línea Celular , Citosol/química , Proteína 58 DEAD Box/fisiología , Humanos , Quinasa I-kappa B/fisiología , Inmunidad Innata , Proteínas Serina-Treonina Quinasas/fisiología , Receptores Inmunológicos , Replicación Viral
20.
Int J Ophthalmol ; 9(11): 1555-1560, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27990356

RESUMEN

AIM: To investigate the role of microRNA-34a (miR-34a) in the induction of apoptosis of human lens epithelial (HLE-B3) cells. METHODS: The apoptosis of HLE-B3 cells was detected by Annexin V-PE apoptosis detection kit after the treatment with 200 µmol/L H2O2 for 24h and lentiviral miR-34a vector transfection. The expression of miR-34a in the cells was quantified by quantitative real time polymerase chain reaction (qRT-PCR) in response to H2O2 exposure and the vector transfection. The effects of overexpression of miR-34a on the expression of B-cell lymphoma-2 (Bcl-2) and silent information regulator 1 (SIRT1) was determined by qRT-PCR and Western blot. RESULTS: The expression of miR-34a was up-regulated by the treatment of H2O2 in HLE-B3 cells. The increased expression of miR-34a is accompanied with the cell apoptosis. Consistence with the H2O2 exposure, ectopic overexpression of miR-34a in HLE-B3 cells promoted cells apoptosis. Importantly the anti-apoptosis factors Bcl-2 and SIRT1 were reduced significantly by up-regulation of miR-34a in HLE-B3 cells. CONCLUSION: MiR-34a promotes the apoptosis of HLE-B3 cells by down-regulating Bcl-2 and SIRT1, suggesting that miR-34a may involve in the pathogenesis of cataract formation and targeting miR-34a may be a potentially therapeutic approach for treatment of cataract.

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