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1.
Stem Cell Res Ther ; 14(1): 184, 2023 07 27.
Artículo en Inglés | MEDLINE | ID: mdl-37501214

RESUMEN

BACKGROUND: Decompensated liver cirrhosis (DLC), a terminal-stage complication of liver disease, is a major cause of morbidity and mortality in patients with hepatopathies. Human umbilical cord mesenchymal stem cell (hUCMSC) therapy has emerged as a novel treatment alternative for the treatment of DLC. However, optimized therapy protocols and the associated mechanisms are not entirely understood. METHODS: We constructed a DLC rat model consistent with the typical clinical characteristics combined use of PB and CCL4. Performing dynamic detection of liver morphology and function in rats for 11 weeks, various disease characteristics of DLC and the therapeutic effect of hUCMSCs on DLC in experimental rats were thoroughly investigated, according to ascites examination, histopathological, and related blood biochemical analyses. Flow cytometry analysis of rat liver, immunofluorescence, and RT-qPCR was performed to examine the changes in the liver immune microenvironment after hucMSCs treatment. We performed RNA-seq analysis of liver and primary macrophages and hUCMSCs co-culture system in vitro to explore possible signaling pathways. PPARγ antagonist, GW9662, and clodronate liposomes were used to inhibit PPAR activation and pre-exhaustion of macrophages in DLC rats' livers, respectively. RESULTS: We found that changing the two key issues, the frequency and initial phase of hUCMSCs infusion, can affect the efficacy of hUCMSCs, and the optimal hUCMSCs treatment schedule is once every week for three weeks at the early stage of DLC progression, providing the best therapeutic effect in reducing mortality and ascites, and improving liver function in DLC rats. hUCMSCs treatment skewed the macrophage phenotype from M1-type to M2-type by activating the PPARγ signaling pathway in the liver, which was approved by primary macrophages and hUCMSCs co-culture system in vitro. Both inhibition of PPARγ activation with GW9662 and pre-exhaustion of macrophages in DLC rats' liver abolished the regulation of hUCMSCs on macrophage polarization, thus attenuating the beneficial effect of hUCMSCs treatment in DLC rats. CONCLUSIONS: These data demonstrated that the optimal hUCMSCs treatment effectively inhibits the ascites formation, prolongs survival and significantly improves liver structure and function in DLC rats through the activation of the PPARγ signaling pathway within liver macrophages. Our study compared the efficacy of different hUCMSCs infusion regimens for DLC, providing new insights on cell-based therapies for regenerative medicine.


Asunto(s)
Ascitis , PPAR gamma , Ratas , Humanos , Animales , PPAR gamma/genética , Ascitis/terapia , Cirrosis Hepática/terapia , Macrófagos , Cordón Umbilical
2.
Stem Cell Res Ther ; 13(1): 465, 2022 09 08.
Artículo en Inglés | MEDLINE | ID: mdl-36076306

RESUMEN

BACKGROUND: Inflammatory bowel diseases (IBD) are chronic relapsing-remitting inflammatory diseases of the gastrointestinal tract that are typically categorized into two subtypes: Crohn's disease (CD) and ulcerative colitis (UC). Although MSCs therapy has achieved encouraging outcomes in IBD therapy, objective responses are limited in colon fibrosis stenosis owing to the complicated microenvironment of CD and MSCs heterogeneity of quality. Here, we chose IFN-γ and kynurenic acid (KYNA) to overcome the low response and heterogeneity of human adipose-derived MSCs (hADSCs) to treat IBD and expand the therapeutic effects based on the excellent ability of IFN-γ and KYNA to promote indoleamine 2,3-dioxygenase-1 (IDO-1) signaling, providing a potential protocol to treat IBD and fibrosis disease. METHODS: hADSCs were isolated, cultured, and identified from human abdominal adipose tissue. The CD pathology-like acute colitis and chronic colon fibrosis rat model was induced by 2,4,6-trinitrobenzen sulfonic acid (TNBS). hADSCs were pretreated in vitro with IFN-γ and KYNA and then were transplanted intravenously at day 1 and 3 of TNBS administration in colitis along with at day 1, 15, and 29 of TNBS administration in chronic colonic fibrosis. Therapeutic efficacy was evaluated by body weights, disease activity index, pathological staining, real-time PCR, Western blot, and flow cytometry. For knockout of IDO-1, hADSCs were transfected with IDO-1-targeting small gRNA carried on a CRISPR-Cas9-lentivirus vector. RESULTS: hADSCs treated with IFN-γ and KYNA significantly upregulated the expression and secretion of IDO-1, which has effectively ameliorated CD pathology-like colitis injury and fibrosis. Notably, the ability of hADSCs with IDO-1 knockout to treat colitis was significantly impaired and diminished the protective effects of the primed hADSCs with IFN-γ and KYNA. CONCLUSION: Inflammatory cytokines IFN-γ- and KYNA-treated hADSCs more effectively alleviate TNBS-induced colitis and colonic fibrosis through an IDO-1-dependent manner. Primed hADSCs are a promising new strategy to improve the therapeutic efficacy of MSCs and worth further research.


Asunto(s)
Colitis , Enfermedad de Crohn , Enfermedades Inflamatorias del Intestino , Células Madre Mesenquimatosas , Animales , Colitis/inducido químicamente , Enfermedad de Crohn/patología , Fibrosis , Humanos , Indolamina-Pirrol 2,3,-Dioxigenasa/genética , Indolamina-Pirrol 2,3,-Dioxigenasa/metabolismo , Enfermedades Inflamatorias del Intestino/metabolismo , Enfermedades Inflamatorias del Intestino/patología , Interferón gamma/genética , Interferón gamma/metabolismo , Ácido Quinurénico/efectos adversos , Ácido Quinurénico/metabolismo , Células Madre Mesenquimatosas/metabolismo , Ratas
3.
Sci Rep ; 12(1): 11029, 2022 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-35773308

RESUMEN

Based on incredibly increasing applications in modern optoelectronic devices, the demand for securing a superior conductive transparent electrode (TCE) candidate becomes significant and urgent. However, boosting both transmittance and conductance simultaneously is an intrinsic limitation. In this work, we present silver nanoscale plasmonic wires (Ag NPWs) to function as TCEs in the visible light region by lowering their corresponding plasma frequencies. By carefully designing geometric dimensions of the Ag NPWs, we also optimize the performance for red, green, and blue colors, respectively. The demonstrated figure of merits for RGB colors appeared respectively 443.29, 459.46, and 133.78 in simulation and 302.75, 344.11, and 348.02 in experiments. Evidently, our Ag NPWs offer much greater FoMs beyond conventional TCEs that are most frequently comprised of indium tin oxide and show further advantages of flexibility and less Moire effect for the applications of flexible and high-resolution optoelectronic devices.

4.
Stem Cell Res Ther ; 12(1): 294, 2021 05 20.
Artículo en Inglés | MEDLINE | ID: mdl-34016164

RESUMEN

BACKGROUND: Liver fibrosis (LF) is a common pathological process characterized by the activation of hepatic stellate cells (HSCs) and accumulation of extracellular matrix. Severe LF causes cirrhosis and even liver failure, a major cause of morbidity and mortality worldwide. Transplantation of human placental mesenchymal stem cells (hPMSCs) has been considered as an alternative therapy. However, the underlying mechanisms and the appropriate time window for hPMSC transplantation are not well understood. METHODS: We established mouse models of CCl4-injured LF and administered hPMSCs at different stages of LF once a week for 2 weeks. The therapeutic effect of hPMSCs on LF was investigated, according to histopathological and blood biochemical analyses. In vitro, the effect of hPMSCs and the secretomes of hPMSCs on the inhibition of activated HSCs was assessed. RNA sequencing (RNA-seq) analysis, real-time PCR array, and western blot were performed to explore possible signaling pathways involved in treatment of LF with hPMSCs. RESULTS: hPMSC treatment notably alleviates experimental hepatic fibrosis, restores liver function, and inhibits inflammation. Furthermore, the therapeutic effect of hPMSCs against mild-to-moderate LF was significantly greater than against severe LF. In vitro, we observed that the hPMSCs as well as the secretomes of hPMSCs were able to decrease the activation of HSCs. Mechanistic dissection studies showed that hPMSC treatment downregulated the expression of fibrosis-related genes, and this was accompanied by the upregulation of Caveolin-1 (Cav1) (p < 0.001). This suggested that the amelioration of LF occurred partly due to the restoration of Cav1 expression in activated HSCs. Upregulation of Cav1 can inhibit the TGF-ß/Smad signaling pathway, mainly by reducing Smad2 phosphorylation, resulting in the inhibition of activated HSCs, whereas this effect could be abated if Cav1 was silenced in advance by siRNAs. CONCLUSIONS: Our findings suggest that hPMSCs could provide multifaceted therapeutic benefits for the treatment of LF, and the TGF-ß/Cav1 pathway might act as a therapeutic target for hPMSCs in the treatment of LF.


Asunto(s)
Células Estrelladas Hepáticas , Células Madre Mesenquimatosas , Animales , Femenino , Humanos , Hígado/patología , Cirrosis Hepática/patología , Cirrosis Hepática/terapia , Ratones , Placenta , Embarazo , Regulación hacia Arriba
5.
Brain ; 144(2): 615-635, 2021 03 03.
Artículo en Inglés | MEDLINE | ID: mdl-33279959

RESUMEN

The molecular pathogenesis of glioblastoma indicates that RTK/Ras/PI3K, RB and TP53 pathways are critical for human gliomagenesis. Here, several transgenic zebrafish lines with single or multiple deletions of nf1, tp53 and rb1 in astrocytes, were established to genetically induce gliomagenesis in zebrafish. In the mutant with a single deletion, we found only the nf1 mutation low-efficiently induced tumour incidence, suggesting that the Nf1 pathway is critical for the initiation of gliomagenesis in zebrafish. Combination of mutations, nf1;tp53 and rb1;tp53 combined knockout fish, showed much higher tumour incidences, high-grade histology, increased invasiveness, and shortened survival time. Further bioinformatics analyses demonstrated the alterations in RTK/Ras/PI3K, cell cycle, and focal adhesion pathways, induced by abrogated nf1, tp53, or rb1, were probably the critical stepwise biological events for the initiation and development of gliomagenesis in zebrafish. Gene expression profiling and histological analyses showed the tumours derived from zebrafish have significant similarities to the subgroups of human gliomas. Furthermore, temozolomide treatment effectively suppressed gliomagenesis in these glioma zebrafish models, and the histological responses in temozolomide-treated zebrafish were similar to those observed in clinically treated glioma patients. Thus, our findings will offer a potential tool for genetically investigating gliomagenesis and screening potential targeted anti-tumour compounds for glioma treatment.


Asunto(s)
Neoplasias Encefálicas/metabolismo , Glioma/metabolismo , Transducción de Señal , Animales , Animales Modificados Genéticamente , Neoplasias Encefálicas/patología , Femenino , Glioma/patología , Masculino , Mutación , Neurofibromatosis 1/metabolismo , Proteína de Retinoblastoma/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Pez Cebra , Proteínas de Pez Cebra/metabolismo
6.
J Cell Biochem ; 121(11): 4337-4346, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32003049

RESUMEN

Diabetic cardiomyopathy can cause cardiac dysfunction and eventually lead to heart failure and sudden death. Long noncoding RNA (lncRNA) Gas5 has been reported to play a function in cardiomyocyte. Here we studied the function of Gas5 on newborn mouse cardiomyocyte (NMC) apoptosis to detect its molecular mechanism. High-glucose treatment was implemented to induce the apoptosis of NMC in this study. And terminal deoxynucleotidyl transferase dUTP nick-end labeling assay, JC-1 assay, and flow cytometry analysis were conducted to know about the apoptosis of NMC when Gas5 and Tcf3 were silenced. Meanwhile, RNA pull-down assay and luciferase reporter assay were conducted to verify the binding of RNAs. Finally, rescue assay was implemented to evaluate the influence on apoptosis situation affected by competing endogenous RNA pathways. Tcf3 was found to bind to the Gas5 promoter to activate the expression of Gas5. Meanwhile, Gas5 and Tcf3 were both found to promote the apoptosis of NMC. Also, mmu-miR-320-3p could bind to Gas5 and Tcf3. Moreover, the Gas5/miR-320-3p/Tcf3 pathway was found to modulate the apoptosis of NMC. In conclusion, Tcf3-activated lncRNA Gas5 regulates NMC apoptosis in diabetic cardiomyopathy.


Asunto(s)
Apoptosis , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Cardiomiopatías Diabéticas/patología , Miocitos Cardíacos/patología , ARN Largo no Codificante/genética , Animales , Animales Recién Nacidos , Células Cultivadas , Cardiomiopatías Diabéticas/etiología , Ratones , Miocitos Cardíacos/metabolismo , Ratas , Transducción de Señal
7.
FASEB J ; 34(1): 1481-1496, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31914615

RESUMEN

As the key factor of the polarity protein complex, Par6 not only regulates polarization processes, but also plays important roles in tumor metastasis and progression in many epithelium malignancy tumors. Here, we showed that Par6 is an essential component in glioma tumorigenesis. Our results indicated the aberrant expression of Par6 in malignant glioma tissues and cell lines. We found that the regulation of Par6 expression induces cell proliferation and tumor growth in vivo and in vitro. Additionally, RNA-seq revealed the effects of Par6 were associated with cyclin D1-regulated cell cycle progression in glioma cells. Moreover, our results demonstrated that the regulation of Par6 can enhance the activation of Akt/PI3K signaling pathway, and subsequently upregulate the expression level of GSK-3ß protein, which then regulate cyclin D1-mediated cell cycle regulation. Furthermore, we found that TGF-ß-induced the upregulation of Par6 expression may be involved in this process. The pathological analysis confirmed the correlation between Par6 expression and the prognosis in human glioma tissues, suggesting the regulation of Par6 expression regulates glioma tumorigenesis and progression. Thus, our findings showed that Par6 might be a potential biomarker for the diagnosis and providing a therapeutic strategy for the treatment of malignant glioma.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/biosíntesis , Biomarcadores de Tumor/biosíntesis , Ciclo Celular , Regulación Neoplásica de la Expresión Génica , Glioma/metabolismo , Transducción de Señal , Proteínas Adaptadoras Transductoras de Señales/genética , Animales , Biomarcadores de Tumor/genética , Línea Celular Tumoral , Ciclina D1/genética , Ciclina D1/metabolismo , Glioma/genética , Glioma/patología , Glucógeno Sintasa Quinasa 3 beta/genética , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Humanos , Masculino , Ratones , Ratones Desnudos , Fosfatidilinositol 3-Quinasas/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo
8.
ACS Sens ; 4(11): 2900-2907, 2019 11 22.
Artículo en Inglés | MEDLINE | ID: mdl-31602973

RESUMEN

We present experimental and theoretical studies of a metamaterial-based plasmonic structure to build a plasmonic-molecular coupling detection system. High molecular sensitivity is realized only when molecules are located in the vicinity of the enhanced field (hot spot region); thus, introducing target molecules in the hot spot region to maximize plasmonic-molecular coupling is crucial to developing the sensing technology. We design a metamaterial consisting of a vertically oriented metal insulator metal (MIM) structure with a 25 nm channel sandwiched between two metal films, which enables the delivery of molecules into the large ravinelike hot spot region, offering an ultrasensitive platform for molecular sensing. This metamaterial is applied to carbon dioxide and butane detection. We design the structure to exhibit resonances at 4033 and 2945 cm-1, which overlap with the C═O and -CH2 vibration modes, respectively. The mutual coupling of these two resonance modes creates a Fano resonance, and their distinct peaks are clearly observed in the corresponding transmission dips. In addition, owing to its small footprint, such a vertical-oriented MIM structure enables us to increase the integration density and allows the detection of a 20 ppm concentration with negligible background noise and high selectivity in the mid-infrared region.


Asunto(s)
Butanos/análisis , Dióxido de Carbono/análisis , Oro/química , Nanopartículas del Metal/química , Nanotecnología , Dióxido de Silicio/química , Resonancia por Plasmón de Superficie , Estructura Molecular
9.
Biosens Bioelectron ; 141: 111209, 2019 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-31357174

RESUMEN

Enhancing the efficiency of antibody protein immobilized on a silicon nanowire-based chip for their antigens detection is reported. An external electric field (EEF) is applied to direct the orientation of antibodies during their immobilization on a chip. Atomic force microscopy (AFM) is used to measure the binding forces between immobilized antibody and targeting antigen under the influence of EEF at different angles. The maximum binding force under a specific angle (optimal angle; oa) of EEF (maxEEFoa) implies the optimal orientation of the antibodies on the chip. In this report, two different cancer carcinoembryonic antigen (CEA)-related cell adhesion molecules 5 (CEACAM5) & 1 (CEACAM1) were used for the examples of disease antigen detection. maxEEFoa of anti-CEACAM5 or anti-CEACAM1 immobilized on a general chip was firstly determined. Spectroscopy of AFM revealed that both binding forces were the largest ones with their antigens when maxEEFoa was applied as compared with no or other angles of EEF. These antibody proteins accompanied with the application of EEF were secondly immobilized on silicon-nanowires (n = 1000) and the field effects were measured (∆I) as their target antigens were approached. Results showed that ∆I was the largest ones when maxEEFoas (225°/270° and 135°/180° for anti-CEACAM5 and anti-CEACAM1, respectively) were applied as compared with other angles of EEF. These observations imply that the silicon nanowires together with the application of maxEEFoa as detection tools could be applied for the cancer diagnostics in the future.


Asunto(s)
Anticuerpos Inmovilizados/química , Antígenos CD/análisis , Técnicas Biosensibles/instrumentación , Antígeno Carcinoembrionario/análisis , Moléculas de Adhesión Celular/análisis , Nanocables/química , Silicio/química , Diseño de Equipo , Proteínas Ligadas a GPI/análisis , Humanos , Análisis por Matrices de Proteínas/instrumentación
10.
Int J Cancer ; 145(6): 1596-1608, 2019 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-31032901

RESUMEN

Heparanase is an endo-ß-d-glucuronidase that cleaves heparan sulfate (HS) side chains of heparan sulfate proteoglycans. Compelling evidence tie heparanase levels with all steps of tumor formation including tumor initiation, growth, metastasis and chemo-resistance, likely involving augmentation of signaling pathways and gene transcription. In order to reveal the molecular mechanism(s) underlying the protumorigenic properties of heparanase, we established an inducible (Tet-on) system in U87 human glioma cells and applied gene array methodology in order to identify genes associated with heparanase induction. We found that CD24, a mucin-like cell adhesion protein, is consistently upregulated by heparanase and by heparanase splice variant devoid of enzymatic activity, whereas heparanase gene silencing was associated with decreased CD24 expression. This finding was further substantiated by a similar pattern of heparanase and CD24 immunostaining in glioma patients (Pearson's correlation; R = 0.66, p = 0.00001). Noteworthy, overexpression of CD24 stimulated glioma cell migration, invasion, colony formation in soft agar and tumor growth in mice suggesting that CD24 functions promote tumor growth. Likewise, anti-CD24 neutralizing monoclonal antibody attenuated glioma tumor growth, and a similar inhibition was observed in mice treated with a neutralizing mAb directed against L1 cell adhesion molecule (L1CAM), a ligand for CD24. Importantly, significant shorter patient survival was found in heparanase-high/CD24-high tumors vs. heparanase-high/CD24-low tumors for both high-grade and low-grade glioma (p = 0.02). Our results thus uncover a novel heparanase-CD24-L1CAM axis that plays a significant role in glioma tumorigenesis.


Asunto(s)
Neoplasias Encefálicas/patología , Antígeno CD24/metabolismo , Glioma/patología , Glucuronidasa/metabolismo , Animales , Neoplasias Encefálicas/metabolismo , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Progresión de la Enfermedad , Femenino , Glioma/metabolismo , Xenoinjertos , Humanos , Ratones , Ratones Endogámicos NOD , Ratones SCID , Molécula L1 de Adhesión de Célula Nerviosa/metabolismo , Transducción de Señal
11.
Biomaterials ; 206: 61-72, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30925289

RESUMEN

Graphene quantum dots (GQDs) are well-known for its potential applications for bioimaging, biosensor, and drug carrier in biomedicine. GQDs are well characteristic of intrinsic peroxidase-like catalytic activity, which is proven effective in scavenging the free radicals, such assuperoxide anion, hydrogen peroxide, and hydroxyl radical. GQDs are also well praised for its low in vivo and in vitro toxicity. Here, we found that nitrogen-doped GQDs (N-GQDs) can strongly disturb redox-sensitive system via the selective inhibition of endogenous antioxidant enzyme activities in zebrafish. The enzyme activities or transcription levels of a battery of hemoproteins including catalase (CAT), superoxide dismutase (SOD), respiratory chain complex I, complex Ⅲ, hemoglobin (Hb), and myeloperoxidase (MPO), were significantly suppressed by N-GQDs. We also found that N-GQDs activated the cytochrome P450 monooxygenase (e.g. cyp1a) and the associated aryl-hydrocarbon receptor repressors (ahrr1 and ahrr2) in zebrafish embryos. Compared to the ultrasmall graphene oxide (USGO), N-GQDs exhibited stronger fluorescent permeability and tissue-specific bio-accumulative effects. Taken together, our findings highlighted that exposure to N-GQDs can disrupt endogenous antioxidant enzyme activities, possibly via the competitive inhibition of electron transfer process. Our results in this study provided solid data for biosafety evaluations of various types of GQDs, and created an alert for the future biomedical applications of N-GQDs.


Asunto(s)
Nitrógeno/química , Puntos Cuánticos/química , Animales , Antioxidantes/química , Catalasa/metabolismo , Grafito/química , Hemoglobinas/metabolismo , Nitrógeno/farmacología , Oxidación-Reducción/efectos de los fármacos , Peroxidasa/metabolismo , Superóxido Dismutasa/metabolismo , Pez Cebra
12.
Medicine (Baltimore) ; 97(31): e11681, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30075561

RESUMEN

BACKGROUND: Balance dysfunctions in stroke survivors are common and have significant impact on functional independence and rehabilitation. As a crucial technique of Traditional Chinese Medicine, acupuncture has been used widely for balance dysfunctions after stroke, although its effective evidence is not clear. Hence, we plan this systematic review protocol to evaluate the value of its efficacy and safety for balance dysfunctions after stroke. METHODS: We will search the databases from the publishment to April 2018: Web of Science, PubMed, Medline, Cochrane Library, EBASE, WHO International Clinical Trials Registry Platform, Wanfang, Chinese Biomedical Literature Database, Chinese Scientific Journal Database (VIP), and China National Knowledge Infrastructure. The clinical efficacy will be accepted as the primary outcomes. RevMan V.5.3 software will be used to compute the data synthesis when a meta-analysis is allowed. RESULTS: This systematic review and meta-analysis will provide a high-quality synthesis of current evidence of acupuncture for balance dysfunctions after stroke including clinical efficacy, balance ability, walking ability, and activity of daily life etcetera. CONCLUSION: This protocol will determine whether acupuncture is an effective and safety intervention for balance dysfunctions after stroke.


Asunto(s)
Terapia por Acupuntura/métodos , Equilibrio Postural/fisiología , Trastornos de la Sensación/terapia , Rehabilitación de Accidente Cerebrovascular/métodos , Accidente Cerebrovascular/complicaciones , Anciano , Protocolos Clínicos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Trastornos de la Sensación/etiología , Accidente Cerebrovascular/fisiopatología , Revisiones Sistemáticas como Asunto , Resultado del Tratamiento
13.
FASEB J ; 32(5): 2814-2826, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29298861

RESUMEN

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is a persistent organic pollutant (POP), an unintentional byproduct of various industrial processes, and a human carcinogen. The expression of the cytochrome P450 1A (cyp1a) gene is upregulated in the presence of TCDD through activating the aryl hydrocarbon receptor pathway in a dose-dependent manner. Several essential response elements, including the 8 potential xenobiotic response elements in the cyp1a promoter region, have been identified to be the main functional parts for the response to TCDD. Thus, we aimed to develop a convenient and sensitive biomonitoring tool to examine the level of POPs in the environment and evaluate its potential human health risks by TCDD. Here, we established a transgenic zebrafish model with a red fluorescent reporter gene ( mCherry) using the truncated cyp1a promoter. Under exposure to TCDD, the expression pattern of mCherry in the reporter zebrafish mirrored that of endogenous cyp1a mRNA, and the primary target tissues for TCDD were the brain vessels, liver, gut, cloaca, and skin. Our results indicated that exposure of the embryos to TCDD at concentrations as low as 0.005 nM for 48 h, which did not elicit morphologic abnormalities in the embryos, markedly increased mCherry expression. In addition, the reporter embryos responded to other POPs, and primary liver cell culture of zebrafish revealed that Cyp1a protein was mainly expressed in the cytoplasm of liver cells. Furthermore, our transgenic fish embryos demonstrated that TCDD exposure can regulate the expression levels of several tumor-related factors, including epidermal growth factor, TNF-α, C-myc, proliferating cell nuclear antigen, TGF-ß, serine/threonine kinase (Akt), and phosphorylated Akt, suggesting that our transgenic fish can be used as a sensitive model to evaluate the carcinogenicity induced by TCDD exposure.-Luo, J.-J., Su, D.-S., Xie, S.-L., Liu, Y., Liu, P., Yang, X.-J., Pei D.-S. Hypersensitive assessment of aryl hydrocarbon receptor transcriptional activity using a novel truncated cyp1a promoter in zebrafish.


Asunto(s)
Citocromo P-450 CYP1A1/biosíntesis , Embrión no Mamífero/metabolismo , Dibenzodioxinas Policloradas/farmacología , Receptores de Hidrocarburo de Aril/metabolismo , Transcripción Genética/efectos de los fármacos , Contaminantes Químicos del Agua/farmacología , Proteínas de Pez Cebra/metabolismo , Animales , Animales Modificados Genéticamente , Citocromo P-450 CYP1A1/genética , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Genes Reporteros , Proteínas Luminiscentes/biosíntesis , Proteínas Luminiscentes/genética , Receptores de Hidrocarburo de Aril/genética , Pez Cebra , Proteínas de Pez Cebra/genética , Proteína Fluorescente Roja
14.
Cell Death Dis ; 9(2): 129, 2018 01 26.
Artículo en Inglés | MEDLINE | ID: mdl-29374157

RESUMEN

Epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) resistance is a major obstacle in the treatment of non-small cell lung cancer (NSCLC). Epigenetic alterations have been shown to be involved in NSCLC oncogenesis; however, their function in EGFR-TKI resistance remains uncharacterized. Here, we found that an EHMT2 inhibitor, UNC0638, can significantly inhibit cell growth and induce apoptosis in EGFR-TKI-resistant NSCLC cells. Additionally, we also found that EHMT2 expression and enzymatic activity levels were elevated in EGFR-TKI-resistant NSCLC cells. Moreover, we determined that genetic or pharmacological inhibition of EHMT2 expression enhanced TKI sensitivity and suppressed migration and tumor sphere formation in EGFR-TKI-resistant NSCLC cells. Further investigation revealed that EHMT2 contributed to PTEN transcriptional repression and thus facilitated AKT pathway activation. The negative relationship between EHMT2 and PTEN was confirmed by our clinical study. Furthermore, we determined that combination treatment with the EHMT2 inhibitor and Erlotinib resulted in enhanced antitumor effects in a preclinical EGFR-TKI-resistance model. We also found that high EHMT2 expression along with low PTEN expression can predict poor overall survival in patients with NSCLC. In summary, our findings showed that EHMT2 facilitated EGFR-TKI resistance by regulating the PTEN/AKT pathway in NSCLC cells, suggesting that EHMT2 may be a target in the clinical treatment of EGFR-TKI-resistant NSCLC.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/genética , Resistencia a Antineoplásicos , Epigénesis Genética/efectos de los fármacos , Receptores ErbB/metabolismo , Antígenos de Histocompatibilidad/metabolismo , N-Metiltransferasa de Histona-Lisina/metabolismo , Neoplasias Pulmonares/genética , Fosfohidrolasa PTEN/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Apoptosis/efectos de los fármacos , Carcinoma de Pulmón de Células no Pequeñas/patología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Resistencia a Antineoplásicos/efectos de los fármacos , Resistencia a Antineoplásicos/genética , Clorhidrato de Erlotinib/farmacología , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Neoplasias Pulmonares/patología , Modelos Biológicos , Fenotipo , Pronóstico , Inhibidores de Proteínas Quinasas/farmacología , Transducción de Señal/efectos de los fármacos , Regulación hacia Arriba/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto
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