Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 11 de 11
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Comp Biochem Physiol C Toxicol Pharmacol ; 231: 108734, 2020 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-32151776

RESUMO

Chromium is toxic to marine animals and can cause damage to many of their organs, including the liver. To test the toxicity of chromium on marine organisms, we exposed the liver of the marine medaka (Oryzias melastigma) with hexavalent chromium [Cr(VI)]. Our results show that Cr enrichment in the liver demonstrates a positive correlation to the exposure concentration. With the increase of Cr(VI) concentration, pathological changes including nuclear migration, cell vacuolization, blurred intercellular gap, nuclear condensation, become noticeable. To further study changes in gene expression in the liver after Cr(VI) exposure, we used RNA-seq to compare expression profiles before and after Cr(VI) exposure. After acute Cr(VI) exposure (2.61 mg/l) for 96 h, 5862 transcripts significantly changed. It is the first time that the PPAR pathway was found to respond sensitively to Cr(VI) exposure in fish. Finally, combined with other published study, we found that there may be some difference between Cr(VI) toxicity in seawater fish and freshwater fish, due to degree of oxidative stress, distribution patterns and detailed Cr(VI) toxicological mechanisms. Not only does our study explore the mechanisms of Cr(VI) toxicity on the livers of marine medaka, it also points out different Cr(VI) toxicity levels and potential mechanisms between seawater fish and freshwater fish.

2.
Environ Sci Technol ; 53(24): 14709-14715, 2019 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-31751126

RESUMO

Since triphenyl phosphate (TPhP) elicits both antiestrogenic activities via blocking the estrogen receptor (ER) and estrogenic activity by elevating 17ß-estradiol (17ß-E2) synthesis, its adverse effect on female reproduction is uncertain. In this study, we exposed Japanese medaka to TPhP at 131, 363, and 1773 ng/L for 100 days following hatching. TPhP significantly induced ovary retardation in all exposure groups (incidence: from 11.9 to 37.8%) and reduced egg production by 38.9 and 50.9% in the 363 and 1773 ng/L exposure groups, respectively. Vitellogenin (vtg) transcription was significantly downregulated by 35.4-57.4% after TPhP exposure, explaining the ovary retardation. Considering that 17ß-E2 was only significantly decreased in the 1773 ng/L exposure group, ER antagonism could be the dominant contributor to the inhibition of vtg transcription and female reproductive toxicity of TPhP. As 4-hydroxyphenyl diphenyl phosphate, a metabolite of TPhP, was detected in livers with similar concentration [68.4-1237 ng/g lipid weight (lw)] to that of TPhP (485-1594 ng/g lw) and elicited medaka ER antagonistic activity (50% inhibitory concentration = 78.1 µM), TPhP and its metabolite should both contribute to the reproductive inhibition. We demonstrate that TPhP at environmentally relevant concentrations is toxic to female reproduction, which poses an ecological risk to wild fish at the population level.

3.
Cell Death Dis ; 10(1): 4, 2018 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-30584245

RESUMO

Endometrial carcinoma is one of the most common malignancies in the female reproductive system. It is well-known that estrogen plays an important role in the pathogenesis of endometrioid endometrial carcinoma (EEC), and induces the cancer suppressor gene PTEN deletion. However, how estrogen affects PTEN expression remains unknown. In the present study, we found in 40 EEC specimens, miR-200c level was higher in most cancer areas than that in the adjacent normal endometrium, while PTEN and PTENP1 were lower. Moreover, the expression of PTEN/PTENP1 and miR-200c also showed a converse relationship in EEC cell lines. In addition, we demonstrated that miR-200c bound directly to PTEN and PTENP1, and PTENP1 could reverse miR-200c inhibition function to PTEN using a dual-luciferase reporter and RNA binding protein immunoprecipitation (RIP) assays. Next, 17ß-estradiol (E2) treatment could improve miR-200c and drop the PTEN level, which caused a consequential increase of the phospho-PI3K-AKT pathway genes. When we stably knocked down estrogen receptor α (ERα) expression in the EEC cell line, the effects of E2 on miR-200c and PTEN declined. In addition, it was demonstrated that E2 might modulate cell proliferation, migration and invasion relying on the expression of miR-200c. Taken together, it can be concluded that estrogen improves the miR-200c level by combining with ER, PTENP1 and PTEN could be inhibited by miR-200c, and then activate the PI3K-AKT pathway. This work provided a new mechanism of EEC development and a new potential therapeutic target.


Assuntos
Carcinoma Endometrioide/metabolismo , Neoplasias do Endométrio/metabolismo , Estrogênios/farmacologia , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , MicroRNAs/metabolismo , PTEN Fosfo-Hidrolase/biossíntese , RNA Neoplásico/metabolismo , Transdução de Sinais/efeitos dos fármacos , Carcinoma Endometrioide/patologia , Linhagem Celular Tumoral , Neoplasias do Endométrio/patologia , Feminino , Humanos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo
4.
J Cell Biochem ; 119(10): 8123-8137, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29923214

RESUMO

The aim of this study is to evaluate the ability of microRNA-183 (miR-183) to influence epithelial-mesenchymal transition (EMT) and cell proliferation, migration, invasion, and apoptosis in endometrial cancer (EC) by targeting cytoplasmic polyadenylation element binding protein 1(CPEB1). EC tissues with matched nonmalignant tissues were collected from 208 EC patients. Ishikawa and RL95-2 cells were selected for cell experiments in vitro and each kind of cells were grouped into blank, negative control (NC), miR-183 mimic, miR-183 inhibitor, CPEB1 overexpression, and miR-183 mimic + CPEB1 overexpression groups. Expressions of miR-183, CPEB1, E-cadherin, and Vimentin were determined by reverse transcription quantitative polymerase chain reaction (RT-qPCR) and Western blotting. Cell viability, colony formation ability, migration, invasion, and apoptosis were assessed by MTT assay, clone formation assay, scratch test, Transwell assay, and flow cytometry. In vivo tumorigenesis of Ishikawa cells was evaluated by tumor formation in nude mice. The miR-183 expression was higher, but the CPEB1 expression was lower in EC tissues than in adjacent nonmalignant tissues. CPEB1 was confirmed as the target of miR-183 by dual-luciferase reporter assay. The miR-183 mimic group had increased cell viability, colony formation ability, cell invasion and migration, tumor volume and weight in nude mice, but decreased cell apoptosis when compared with the blank group. The expression of E-cadherin was down-regulate, but expression of Vimentin was up-regulate in the miR-183 mimic group in comparison with the blank group. In terms of a comparison between the blank group and CPEB1 overexpression group, the CPEB1 overexpression group had suppressed cell viability, colony formation ability, cell invasion and migration, tumor volume and weight, but increased cell apoptosis. The expression of E-cadherin was up-regulated, but the expression of Vimentin was down-regulated in the CPEB1 overexpression group in comparison with the blank group. The miR-183 mimic + CPEB1 overexpression group had higher miR-183 expression than the blank group. These findings indicate that miR-183 induces EMT, inhibits apoptosis, and promotes cell proliferation, migration, invasion, and in vivo tumorigenesis in EC by targeting CPEB1.


Assuntos
Sobrevivência Celular/fisiologia , Neoplasias do Endométrio/genética , Neoplasias do Endométrio/patologia , Transição Epitelial-Mesenquimal/fisiologia , MicroRNAs/genética , Fatores de Transcrição/metabolismo , Fatores de Poliadenilação e Clivagem de mRNA/metabolismo , Animais , Western Blotting , Linhagem Celular , Linhagem Celular Tumoral , Movimento Celular/genética , Movimento Celular/fisiologia , Proliferação de Células/genética , Proliferação de Células/fisiologia , Sobrevivência Celular/genética , Transição Epitelial-Mesenquimal/genética , Feminino , Citometria de Fluxo , Humanos , Camundongos , Camundongos Nus , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição/genética , Fatores de Poliadenilação e Clivagem de mRNA/genética
6.
J Cancer ; 8(2): 305-313, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28243335

RESUMO

miR-BART22, a new discovered Epstein-Barr virus (EBV) miRNA, is abundant in Nasopharyngeal carcinoma (NPC). It has been reported that miR-BART22 promoted the tumor development by down-modulating EBV LMP2 expression to evade the host immune response. But its cell target genes have still been obscure. We have reported an inverse correlation between the BART-22 and MAP3K5 protein expression in NPC tissues and NPC cell lines. Meanwhile, MAP3K5 protein expression level was significantly decreased in primary NPC tissues compared with nasopharyngitis when MAP3K5 mRNA expression was consistent in two group tissues. According to our data and target prediction by miRnada, we assume MAP3K5 is an important target gene of NPC. MAP3K5, also named apoptosis signal-regulating kinase1 (ASK1), is an important early answer gene in P38MAPK pathway and an apoptosis-related gene. In present study, MAP3K5 was verified the target gene of miR-BART22 by luciferase assay. miRBART-22 decreased MAP3K5 protein level. Moreover, it also decreased MAP3K5 downstream gene MAP2K4 expression in P38MAPK pathway, and even their activated phosphorylation forms. Additionally, we found stable transfection of miR-BAT22 could improve tumor cells' proliferative and invasive abilities in NPC cell line 5-8F. The data highlight the role of the EBV miR-BART22 in regulating genes involving in apoptosis and some important pathways to promote cancer development. And it also raises the possibility that inhibitors of miR-BART22 can be as a therapeutic strategy for NPC and other EBV-infected tumors treatment.

7.
Cancer Lett ; 383(1): 28-40, 2016 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-27693631

RESUMO

Endometrioid endometrial carcinoma (EEC) is the most common gynecologic malignancy around the world. Epithelial-to-mesenchymal transition (EMT) is a core process during EEC cell invasion. The abnormal expression of the long noncoding RNA metastasis associated lung adenocarcinoma transcript 1 (MALAT1) or miR-200 family members were shown to facilitate EMT in multiple human cancers, but the regulatory mechanism by which MALAT1 and miR-200 act remains unknown. Previous studies have shown that miR-200 family members are enriched in EEC as well as melanoma and some ovarian carcinomas. In the present study, we first showed that miR-200c levels were higher in most EEC specimens than in non-tumor tissues, while MALAT1 levels were lower. Moreover, we found that miR-200c bound directly to MALAT1 using luciferase reporter and qRT-PCR assays. MALAT1 and miR-200c are reciprocally repressed, and TGF-ß increased MALAT1 expression by inhibiting miR-200c. When the interaction between miR-200c/MALAT1 was interrupted, the invasive capacity of EEC cells was decreased and EMT markers expression were altered in vitro. A xenograft tumor model was used to show that targeting the miR-200c/MALAT1 axis inhibited EEC growth and EMT-associated protein expression in vivo. In summary, miR-200c/MALAT1 axis is a target with therapeutic potential in EEC. However, different expression model of miR-200c and MALAT1 in EEC with that in other organ carcinomas needs further mechanism researches.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma Endometrioide/metabolismo , Movimento Celular , Neoplasias do Endométrio/metabolismo , MicroRNAs/metabolismo , RNA Longo não Codificante/metabolismo , Regiões 3' não Traduzidas , Animais , Sítios de Ligação , Biomarcadores Tumorais/genética , Carcinoma Endometrioide/genética , Carcinoma Endometrioide/patologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Neoplasias do Endométrio/genética , Neoplasias do Endométrio/patologia , Transição Epitelial-Mesenquimal , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , MicroRNAs/genética , Invasividade Neoplásica , Interferência de RNA , RNA Longo não Codificante/genética , Transdução de Sinais , Fatores de Tempo , Transfecção , Fator de Crescimento Transformador beta/farmacologia , Carga Tumoral
8.
Genes (Basel) ; 7(6)2016 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-27271671

RESUMO

We aimed to identify endometrioid endometrial carcinoma (EEC)-related gene signatures using a multi-step miRNA-mRNA regulatory network construction approach. Pathway analysis showed that 61 genes were enriched on many carcinoma-related pathways. Among the 14 highest scoring gene signatures, six genes had been previously shown to be endometrial carcinoma. By qRT-PCR and next generation sequencing, we found that a gene signature (CPEB1) was significantly down-regulated in EEC tissues, which may be caused by hsa-miR-183-5p up-regulation. In addition, our literature surveys suggested that CPEB1 may play an important role in EEC pathogenesis by regulating the EMT/p53 pathway. The miRNA-mRNA network is worthy of further investigation with respect to the regulatory mechanisms of miRNAs in EEC. CPEB1 appeared to be a tumor suppressor in EEC. Our results provided valuable guidance for the functional study at the cellular level, as well as the EEC mouse models.

9.
Tumour Biol ; 37(2): 2425-33, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26383521

RESUMO

Cyclin-dependent kinase 4 (CDK4) is a member of cyclin-dependent kinase family which regulates G1 to S cell cycle transition. CDK4 activity is increased in many tumor types. Here, we report a negative automodulatory feedback loop between CDK4 and miR-16 that regulates cell cycle progression in nasopharyngeal carcinoma (NPC). By miRNA array and real-time PCR, we identified upregulation of tumor suppressor miR-16a, which inhibited cell cycle progression and sensitized NPC cells to chemotherapy. CDK4 knockdown reduced the expression of c-Myc, the latter of which directly suppresses the miR-16 expression by directly binding to the miR-16 promoter. Moreover, we found that miR-16 upregulation could reduce CDK4 expression by repressing CCND1 and thus forms a feedback loop via the CDK4/c-Myc/miR-16/CCND1 pathway. Finally, miR-16 was negatively correlated with CDK4 expression in NPC biopsies. In summary, our results define a double-negative feedback loop involving CDK4 and miR-16 mediated by c-Myc that modulates NPC cell growth and chemotherapy sensitivity.


Assuntos
Proliferação de Células/genética , Quinase 4 Dependente de Ciclina/genética , MicroRNAs/genética , Neoplasias Nasofaríngeas/genética , Proteínas Proto-Oncogênicas c-myc/genética , Animais , Antineoplásicos/farmacologia , Carcinoma , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ciclina D1/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/genética , Técnicas de Silenciamento de Genes/métodos , Genes Supressores de Tumor/efeitos dos fármacos , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/tratamento farmacológico , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/genética
10.
Langmuir ; 30(50): 15229-37, 2014 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-25489918

RESUMO

Although the hydrogel network has been widely investigated as a carrier for enzyme immobilization, to in situ encapsulate enzymes into a hydrogel network in an efficient, practical, and active way is still one of the great challenges in the field of biochemical engineering. Here, we report a new protocol to address this issue by encapsulating enzyme into poly(ethylene glycol) (PEG) hydrogel network grafted on polymeric substrates. In our strategy, isopropyl thioxanthone semipinacol (ITXSP) dormant groups were first planted onto the surface of a plastic matrix with low density polyethylene (LDPE) film as a model by a UV-induced abstracting hydrogen-coupling reaction. As a proof of concept, lipase, which could catalyze esterification of glucose with palmitic acid, then was in situ net-immobilized into a PEG-based hydrogel network layer through a visible light-induced surface controlled/living graft cross-linking polymerization. This strategy demonstrates the following novel significant merits: (1) in comparison with the UV irradiation or high temperature, the visible light and room temperature used provide a friendly condition to maintain activity of enzyme during immobilization; (2) the uniqueness of controlled/living cross-linking polymerization not only makes it easy to form a uniform PEG hydrogel network, which is a benefit to avoid the leakage of net-immobilizing enzyme, but also to tune the net-thickness or capacity to accommodate enzyme; and (3) as compared to systems of nanoparticles and porous matrixes, the flexible/robust end-products of the surface net-immobilizing enzyme with polymer film are more suitable to be applied in a bioreactor due to their features of easier separation and reuse. We confirmed that this catalytic film could retain almost all of its initial activity after seven batches of 24 h esterifications. The proposed strategy provides an extremely simple, effective, and flexible method for enzyme immobilization.


Assuntos
Enzimas Imobilizadas/química , Hidrogéis/química , Polietilenoglicóis/química , Animais , Biocatálise , Cápsulas , Enzimas Imobilizadas/metabolismo , Luz , Lipase/química , Processos Fotoquímicos , Polietileno/química , Polimerização , Solventes/química , Propriedades de Superfície , Suínos , Xantonas/química
11.
Lab Chip ; 14(14): 2505-14, 2014 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-24852169

RESUMO

Protein microarrays have become vital tools for various applications in biomedicine and bio-analysis during the past decade. The intense requirements for a lower detection limit and industrialization in this area have resulted in a persistent pursuit to fabricate protein microarrays with a low background and high signal intensity via simple methods. Here, we report on an extremely simple strategy to create three-dimensional (3D) protein microarrays with an anti-fouling background and a high protein capacity by photo-induced surface sequential controlled/living graft polymerization developed in our lab. According to this strategy, "dormant" groups of isopropyl thioxanthone semipinacol (ITXSP) were first introduced to a polymeric substrate through ultraviolet (UV)-induced surface abstraction of hydrogen, followed by a coupling reaction. Under visible light irradiation, the ITXSP groups were photolyzed to initiate surface living graft polymerization of poly(ethylene glycol) methyl methacrylate (PEGMMA), thus introducing PEG brushes to the substrate to generate a full anti-fouling background. Due to the living nature of this graft polymerization, there were still ITXSP groups on the chain ends of the PEG brushes. Therefore, by in situ secondary living graft cross-linking copolymerization of glycidyl methacrylate (GMA) and polyethylene glycol diacrylate (PEGDA), we could finally plant height-controllable cylinder microarrays of a 3D PEG network containing reactive epoxy groups onto the PEG brushes. Through a commonly used reaction of amine and epoxy groups, the proteins could readily be covalently immobilized onto the microarrays. This delicate design aims to overcome two universal limitations in protein microarrays: a full anti-fouling background can effectively eliminate noise caused by non-specific absorption and a 3D reactive network provides a larger protein-loading capacity to improve signal intensity. The results of non-specific protein absorption tests demonstrated that the introduction of PEG brushes greatly improved the anti-fouling properties of the pristine low-density polyethylene (LDPE), for which the absorption to bovine serum albumin was reduced by 83.3%. Moreover, the 3D protein microarrays exhibited a higher protein capacity than the controls to which were attached the same protein on PGMA brushes and monolayer epoxy functional groups. The 3D protein microarrays were used to test the immunoglobulin G (IgG) concentration in human serum, suggesting that they could be used for biomedical diagnosis, which indicates that more potential bio-applications could be developed for these protein microarrays in the future.


Assuntos
Imunoglobulina G/sangue , Análise Serial de Proteínas , Animais , Bovinos , Humanos , Polietileno/química , Polietilenoglicóis/química , Polimetil Metacrilato , Análise Serial de Proteínas/instrumentação , Análise Serial de Proteínas/métodos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA