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1.
Cell Death Dis ; 15(1): 82, 2024 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-38263290

RESUMO

The matrix metalloprotease A disintegrin and metalloprotease with thrombospondin motifs 1 (ADAMTS1) was reported to be involved in tumor progression in several cancer types, but its contributions appear discrepant. At present, the role of ADAMTS1 in oral squamous cell carcinoma (SCC; OSCC) remains unclear. Herein, The Cancer Genome Atlas (TCGA) database showed that ADAMTS1 transcripts were downregulated in head and neck SCC (HNSCC) tissues compared to normal tissues, but ADAMTS1 levels were correlated with poorer prognoses of HNSCC patients. In vitro, we observed that ADAMTS1 expression levels were correlated with the invasive abilities of four OSCC cell lines, HSC-3, SCC9, HSC-3M, and SAS. Knockdown of ADAMTS1 in OSCC cells led to a decrease and its overexpression led to an increase in cell-invasive abilities in vitro as well as tumor growth and lymph node (LN) metastasis in OSCC xenografts. Mechanistic investigations showed that the cyclic increase in ADAMTS1-L1 cell adhesion molecule (L1CAM) axis-mediated epidermal growth factor receptor (EGFR) activation led to exacerbation of the invasive abilities of OSCC cells via inducing epithelial-mesenchymal transition (EMT) progression. Clinical analyses revealed that ADAMTS1, L1CAM, and EGFR levels were all correlated with worse prognoses of HNSCC patients, and patients with ADAMTS1high/L1CAMhigh or EGFRhigh tumors had the shortest overall and disease-specific survival times. As to therapeutic aspects, we discovered that an edible plant-derived flavonoid, apigenin (API), drastically inhibited expression of the ADAMTS1-L1CAM-EGFR axis and reduced the ADAMTS1-triggered invasion and LN metastasis of OSCC cells in vitro and in vivo. Most importantly, API treatment significantly prolonged survival rates of xenograft mice with OSCC. In summary, ADAMTS1 may be a useful biomarker for predicting OSCC progression, and API potentially retarded OSCC progression by targeting the ADAMTS1-L1CAM-EGFR signaling pathway.


Assuntos
Proteína ADAMTS1 , Receptores ErbB , Neoplasias Bucais , Molécula L1 de Adesão de Célula Nervosa , Carcinoma de Células Escamosas de Cabeça e Pescoço , Animais , Humanos , Camundongos , Apigenina , Transição Epitelial-Mesenquimal , Metástase Linfática
2.
Nutrients ; 15(16)2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37630706

RESUMO

Rice bran, a byproduct of rice milling, is rich in fiber and phytochemicals and confers several health benefits. However, its effects on gut microbiota and obesity-related muscle atrophy in postmenopausal status remain unclear. In this study, we investigated the effects of rice bran on gut microbiota, muscle synthesis, and breakdown pathways in estrogen-deficient ovariectomized (OVX) mice receiving a high-fat diet (HFD). ICR female mice were divided into five groups: sham, OVX mice receiving control diet (OC); OVX mice receiving HFD (OH); OVX mice receiving control diet and rice bran (OR); and OVX mice receiving HFD and rice bran (OHR). After twelve weeks, relative muscle mass and grip strength were high in rice bran diet groups. IL-6, TNF-α, MuRf-1, and atrogin-1 expression levels were lower, and Myog and GLUT4 were higher in the OHR group. Rice bran upregulated the expression of occludin and ZO-1 (gut tight junction proteins). The abundance of Akkermansiaceae in the cecum was relatively high in the OHR group. Our finding revealed that rice bran supplementation ameliorated gut barrier dysfunction and gut dysbiosis and also maintained muscle mass by downregulating the expression of MuRf-1 and atrogin-1 (muscle atrophy-related factors) in HFD-fed OVX mice.


Assuntos
Dieta Hiperlipídica , Oryza , Feminino , Animais , Camundongos , Camundongos Endogâmicos ICR , Dieta Hiperlipídica/efeitos adversos , Disbiose , Atrofia Muscular/etiologia , Atrofia Muscular/prevenção & controle , Suplementos Nutricionais
3.
Artigo em Inglês | MEDLINE | ID: mdl-37482638

RESUMO

BACKGROUND AND OBJECTIVES: Many studies have confirmed the influences of various service quality dimensions on patient satisfaction and loyalty, but no existing theoretical model accounts for variation in how different types of patients evaluate service quality's soft and hard attributes. This research gap may cause problems for administrators needing to decide how to distribute resources appropriately across multiple departments. Therefore, this study establishes a theoretical model of the differences between inpatients' and outpatients' evaluations of hard and soft qualities and compares such evaluations' influences on patient satisfaction and loyalty. Also, to supplement statistical analysis and respond to scholars' calls for more mixed-methods studies of health care quality, this research incorporates analysis of online reviews to provide a holistic, close to real-time picture of patients' service experience perceptions. METHODS: This study's survey sample comprised 292 inpatients and 137 outpatients from a Taiwanese hospital. We used partial least squares structural equation modeling to test the hypothetical model and importance-performance map analysis to identify factors that were significant to the service process but performed poorly. Finally, we used a text-mining technique to scrape 536 reviews posted on Google Maps, and Leximancer Portal to perform automated content and sentiment analyses on those data, as a means of mapping the critical concepts and themes that influenced patient experiences. RESULTS: This study's analyses support the ideas that both hard and soft qualities are critical dimensions of service quality, and that each has different influences on inpatients' and outpatients' satisfaction and loyalty. Specifically, the sampled inpatients strongly valued the hard qualities of the hospital but were not satisfied with it. On the other hand, soft qualities attracted outpatients' attention and influenced their satisfaction and loyalty. In addition, content analysis revealed that soft qualities were the main reason patients left comments, whether positive or negative. Waiting time emerged as another critical element in triggering patients' unfavorable reviews. CONCLUSIONS: Patient population type, whether inpatient or outpatient, has been found to impact perceptions of service quality within health care institutions. As such, health care administrators should be cognizant of this phenomenon and make informed and tailored decisions when addressing quality within their respective services. Emphasis on the development of both interpersonal and professional skills among health care personnel may prove beneficial in enhancing the patient experience and ultimately fostering positive online reviews.

4.
Int J Mol Sci ; 23(21)2022 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-36361527

RESUMO

Long noncoding (lnc)RNAs are reported to be key regulators of tumor progression, including hepatocellular carcinoma (HCC). The lncRNA long intergenic noncoding RNA 00673 (LINC00673) was indicated to play an important role in HCC progression, but the impacts of genetic variants (single-nucleotide polymorphisms, SNPs) of LINC00673 on HCC remain unclear. A TaqMan allelic discrimination assay was performed to analyze the genotypes of three tagging SNPs, viz., rs9914618 G > A, rs6501551 A > G, and rs11655237 C > T, of LINC00673 in 783 HCC patients and 1197 healthy subjects. Associations of functional SNPs of LINC00673 with HCC susceptibility and clinicopathologic variables were analyzed by logistic regression models. After stratification by confounding factor, we observed that elderly patients (≥60 years) with the LINC00673 rs9914618 A allele had an increased risk of developing HCC under a codominant model (p = 0.025) and dominant model (p = 0.047). Moreover, elderly patients carrying the GA + AA genotype of rs9914618 exhibited a higher risk of having lymph node metastasis compared to those who were homozygous for the major allele (p = 0.013). Genotype screening of rs9914618 in HCC cell lines showed that cells carrying the AA genotype expressed higher LINC00673 levels compared to the cells carrying the GG genotype. Further analyses of clinical datasets from the Cancer Genome Atlas (TCGA) showed that LINC00673 expressions were upregulated in HCC tissues compared to normal tissues, and were correlated with advanced clinical stages and poorer prognoses. In conclusions, our results suggested that the LINC00673 rs9914618 polymorphism may be a promising HCC biomarker, especially in elderly populations.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , RNA Longo não Codificante , Idoso , Humanos , Alelos , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Estudos de Casos e Controles , Predisposição Genética para Doença , Genótipo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Polimorfismo de Nucleotídeo Único , RNA Longo não Codificante/genética , Pessoa de Meia-Idade
5.
Expert Opin Ther Targets ; 26(4): 375-388, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35361044

RESUMO

BACKGROUND: GO-Y078, a new synthetic analogue of curcumin (CUR), has higher oral bioavailability and anticancer activity than CUR, but the oncostatic effect of GO-Y078 on oral squamous cell carcinoma (OSCC) is largely unknown. RESEARCH DESIGN AND METHODS: In the present study, we examined the oncostatic properties and possible mechanisms of GO-Y078 on human SCC-9 and HSC-3 OSCC cells. RESULTS: Our results indicated that GO-Y078 showed a cytostatic effect against OSCC cells, and this antiproliferative phenomenon stemmed from a mechanism involving multiple levels of cooperation, including cell-cycle G2/M arrest and apoptosis induction. Mechanistically, GO-Y078 treatment induced caspase-mediated apoptosis via upregulating two apoptosis-modulating proteins, SMAC/DIABLO and heme oxygenase (HO)-1. GO-Y078 transcriptionally induced upregulation of the HO-1 gene by increasing the AP-1 DNA-binding activity, which was initiated by activation of the p38 /JNK1/2 pathways. In the clinic, patients with head and neck cancers expressed lower HO-1 and SMAC/DIABLO levels in primary cancer tissues compared to normal tissues. Clinical datasets also revealed that patients with head and neck cancers expressing high HO-1 had afavorable prognosis. CONCLUSIONS: Our results provide new insights into the role of GO-Y078-induced molecular regulation in suppressing OSCC growth and suggest that GO-Y078 has potential therapeutic applications for OSCC.


Assuntos
Carcinoma de Células Escamosas , Curcumina , Neoplasias de Cabeça e Pescoço , Neoplasias Bucais , Apoptose , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Curcumina/análogos & derivados , Curcumina/farmacologia , Curcumina/uso terapêutico , DNA/farmacologia , DNA/uso terapêutico , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Heme Oxigenase-1/metabolismo , Heme Oxigenase-1/farmacologia , Heme Oxigenase-1/uso terapêutico , Humanos , Neoplasias Bucais/tratamento farmacológico , Neoplasias Bucais/metabolismo , Neoplasias Bucais/patologia , Fator de Transcrição AP-1/metabolismo , Fator de Transcrição AP-1/farmacologia , Fator de Transcrição AP-1/uso terapêutico , Ativação Transcricional
6.
J Hosp Leis Sport Tour Educ ; 30: 100374, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35221798

RESUMO

Despite dissertation's significance in enhancing the quality of scholarly outputs in tourism and hospitality fields, insufficient research investigates the challenges and disruptions students experience amidst a public health crisis. This study aims to fill the research gaps and integrate attribution and self-efficacy theories to understand how the COVID-19 pandemic influences students' decision-making and behaviours during the dissertation writing process. Qualitative exploration with 15 graduate students was conducted. The results indicate that adjustment of data collection approaches was the most shared external challenge, while students' religious background and desire for publishing COVID related topics were primary internal motivations.

7.
Artigo em Inglês | MEDLINE | ID: mdl-31771182

RESUMO

As a non-invasive method, heart rate variability (HRV) has been widely used to study cardiovascular autonomous control. Environmental epidemiological studies indicated that the increase in an average concentration of particulate matter (PM) would result in a decrease in HRV, which was related to the increase of cardiovascular mortality in patients with myocardial infarction and the general population. With rapid economic and social development in Asia, how air pollutants, such as PM of different sizes and their components, affect the cardiovascular health of older people, still need to be further explored. The current study includes a 72 h personal exposure monitoring of seven healthy older people who lived in the Taipei metropolitan area. Mobile equipment, a portable electrocardiogram recorder, and the generalized additive mixed model (GAMM) were adopted to evaluate how HRV indices were affected by size-fractionated PM, particle-bound polycyclic aromatic hydrocarbons (p-PAHs), black carbon (BC), and carbon monoxide (CO). Other related confounding factors, such as age, sex, body mass index (BMI), temperature, relative humidity (RH), time, and monitoring week were controlled by fixed effects of the GAMM. Statistical analyses of multi-pollutant models showed that PM2.5-10, PM1, and nanoparticle (NP) could cause heart rate (HR), time-domain indices, and frequency-domain indices to rise; PM1-2.5 and BC would cause the frequency-domain index to rise; p-PAHs would cause HR to rise, and CO would cause time-domain index and frequency-domain index to decline. In addition, the moving average time all fell after one hour and might appear at 8 h in HRVs' largest percentage change caused by each pollutant, results of which suggested that size-fractionated PM, p-PAHs, BC, and CO exposures have delayed effects on HRVs. In conclusion, the results of the study showed that the increase in personal pollutant exposure would affect cardiac autonomic control function of healthy older residents in metropolitan areas, and the susceptibility of cardiovascular effects was higher than that of healthy young people. Since the small sample size would limit the generalizability of this study, more studies with larger scale are warranted to better understand the HRV effects of simultaneous PM and other pollution exposures for subpopulation groups.


Assuntos
Carbono/toxicidade , Frequência Cardíaca/efeitos dos fármacos , Nanopartículas/toxicidade , Material Particulado/toxicidade , Adolescente , Idoso , Idoso de 80 Anos ou mais , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Carbono/química , Monóxido de Carbono/análise , Poluentes Ambientais/análise , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Tamanho da Partícula , Hidrocarbonetos Policíclicos Aromáticos/análise , Taiwan
8.
J Infect Dev Ctries ; 10(12): 1357-1361, 2016 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-28036317

RESUMO

Mycobacterium fortuitum group (M. fortuitum), also known as rapidly growing Mycobacteria, can cause pyogenic infections in human beings, most commonly in immunocompromised patients. Herein, we present a 40-year-old immunocompetent male patient who underwent planned excision of a sebaceous cyst in the abdominal wall. He suffered from tender erythematous lesions with purulent discharge around the healing wound that developed 2 weeks after surgery. Gram stain, bacterial and fungal culture results of the wound were negative. A diagnosis of non-tuberculous mycobacteria was made from a wound culture from the area of operative debridement, which was subsequently confirmed to be M. fortuitum group using PCR-restriction fragment length polymorphism analysis of the hsp65 gene. The patient received 4 weeks of parenteral imipenem/cilastatin 500 mg every 6 hours and amikacin 500 mg every 12 hours, plus oral clarithromycin 500 mg twice daily, and the wound recovered completely. He was discharged and followed up regularly at our outpatient clinic, and continued taking oral ciprofloxacin and clarithromycin 500 mg twice daily for 6 months. This case highlights the importance of strict aseptic precautions even during minor procedures, and also the characteristics of M. fortuitum infections in immunocompetent patients, which usually develop as localized postsurgical wound infections. We also share our experience in successfully treating a M. fortuitum complicated skin and soft tissue infection.


Assuntos
Cisto Epidérmico/cirurgia , Infecções por Mycobacterium não Tuberculosas/diagnóstico , Mycobacterium fortuitum/isolamento & purificação , Dermatopatias Bacterianas/diagnóstico , Infecções dos Tecidos Moles/diagnóstico , Infecção da Ferida Cirúrgica/diagnóstico , Adulto , Antibacterianos/uso terapêutico , Desbridamento , Humanos , Masculino , Infecções por Mycobacterium não Tuberculosas/microbiologia , Infecções por Mycobacterium não Tuberculosas/patologia , Infecções por Mycobacterium não Tuberculosas/terapia , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Pele/microbiologia , Pele/patologia , Dermatopatias Bacterianas/microbiologia , Dermatopatias Bacterianas/patologia , Dermatopatias Bacterianas/terapia , Infecções dos Tecidos Moles/microbiologia , Infecções dos Tecidos Moles/patologia , Infecções dos Tecidos Moles/terapia , Infecção da Ferida Cirúrgica/microbiologia , Infecção da Ferida Cirúrgica/patologia , Infecção da Ferida Cirúrgica/terapia , Taiwan
9.
Adv Exp Med Biol ; 923: 337-343, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27526161

RESUMO

Typically, continuous wave spectroscopy (CWS) can be used to accurately quantify biological tissue optical properties (µ a and µ s ') by employing the diffuse reflectance information acquired at multiple source-detector separations (multi-distance). On the other hand, sample optical properties can also be obtained by fitting multi-wavelength light reflectance acquired at a single source detector separation to the diffusion theory equation. To date, multi-wavelength and multi-distance methods have not yet been rigorously compared for their accuracy in quantification of the sample optical properties. In this investigation, we compared the accuracy of the two above-mentioned quantifying methods in the optical properties recovery. The liquid phantoms had µ a between 0.004 and 0.011 mm(-1) and µ s ' between 0.55 and 1.07 mm(-1) whose optical properties mimic the human breast. Multi-distance data and multi-wavelength data were fitted to the same diffusion equation for consistency. The difference between benchmark µ a and µ s ' and the fitted results, ΔError (ΔE) was used to evaluate the accuracy of the two methods. The results showed that either method yielded ΔE within 15-30 % when values were within certain limits to standard values applicable to µ s ' and µ a for human adipose tissue. Both methods showed no significant differences in ΔE values. Our results suggest that both multi-distance and multi-wavelength methods can yield similar reasonable optical properties in biological tissue with a proper calibration.


Assuntos
Tecido Adiposo/química , Modelos Teóricos , Óptica e Fotônica/métodos , Processamento de Sinais Assistido por Computador , Análise Espectral/métodos , Algoritmos , Compostos de Anilina/química , Calibragem , Simulação por Computador , Difusão , Emulsões/química , Humanos , Método de Monte Carlo , Óptica e Fotônica/normas , Imagens de Fantasmas , Fosfolipídeos/química , Reprodutibilidade dos Testes , Óleo de Soja/química , Análise Espectral/normas
10.
Int J Mol Sci ; 17(7)2016 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-27347940

RESUMO

Oral cancer is a common cancer with poor prognosis. We evaluated the expression of PBK/TOPK (PDZ-binding kinase/T-LAK cell-originated protein kinase) and its prognostic significance in oral cancer. PBK/TOPK expression was measured by immunohistochemical staining of samples from 287 patients with oral cancer. The association between PBK/TOPK expression and clinicopathological features was analyzed. The prognostic value of PBK/TOPK for overall survival was determined by Kaplan-Meier analysis and Cox proportional hazard models. A high PBK/TOPK expression level was correlated with long overall survival. The prognostic role of PBK/TOPK expression was significant in young patients (p < 0.05), patients with smoking habits (p < 0.05), and late stage disease (p < 0.05). Our results suggest that PBK/TOPK expression is enhanced in oral cancer. High PBK/TOPK expression, either alone or in subgroups according to clinicopathological features, may serve as a favorable prognostic marker for patients with oral cancer.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma de Células Escamosas/metabolismo , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Neoplasias Bucais/metabolismo , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/genética , Carcinoma de Células Escamosas/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Quinases de Proteína Quinase Ativadas por Mitógeno/genética , Neoplasias Bucais/patologia
11.
Cancer Chemother Pharmacol ; 75(5): 879-86, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25424280

RESUMO

Macroautophagy is widely accepted as a cytoprotective mechanism against various environmental stresses. While inhibition of autophagy is generally considered to increase the susceptibility of cancer cells to therapeutic agents, whether it also plays a similar role in tumor stem cells is unclear and still controversial. With increased attention and efforts focused on the cytoprotective feature of autophagy in cancer, it is also essential to understand its role in the biology of cancer stem cells, including self-renewal, differentiation, and tumorigenicity. Although there are very few studies that evaluate autophagy in cancer stem/progenitor cells, understanding the mechanisms governing autophagic responses in various cancer stem cells could provide support for the future development of clinical therapeutics. The present review summarizes current studies that assess the role of autophagy in various types of cancer stem cells and those that evaluate the application of inhibitors of key components within the autophagy pathway in cancer stem/progenitor cells.


Assuntos
Neoplasias/patologia , Células-Tronco Neoplásicas/patologia , Animais , Antineoplásicos/farmacologia , Autofagia/efeitos dos fármacos , Autofagia/fisiologia , Humanos , Neoplasias/tratamento farmacológico , Células-Tronco Neoplásicas/efeitos dos fármacos
12.
JIMD Rep ; 11: 165-72, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23700290

RESUMO

BACKGROUND: Fatty acid oxidation (FAO) disorders are a heterogeneous group of inborn errors in the transportation and oxidation of fatty acids. FAO disorders were thought to be very rare in the Chinese population. Newborn screening for FAO disorders beginning in 2002 in Taiwan may have increased the diagnosis of this group of diseases. MATERIALS AND METHODS: Till 2012, the National Taiwan University Hospital Newborn Screening Center screened more than 800,000 newborns for FAO disorders. Both patients diagnosed through screening and patients detected after clinical manifestations were included in this study. RESULTS: A total of 48 patients with FAO disorders were identified during the study period. The disorders included carnitine palmitoyltransferase I deficiency, carnitine acylcarnitine translocase deficiency, carnitine palmitoyltransferase II deficiency, very long-chain acyl-CoA dehydrogenase deficiency, medium-chain acyl-CoA dehydrogenase deficiency, multiple acyl-CoA dehydrogenase deficiency, short-chain defects, and carnitine uptake defect. Thirty-nine patients were diagnosed through newborn screening. Five false-negative newborn screening cases were noted during this period, and four patients who were not screened were diagnosed based on clinical manifestations. The ages of all patients ranged from 6 months to 22.9 years (mean age 6.6 years). Except for one case of postmortem diagnosis, there were no other mortalities. CONCLUSIONS: The combined incidence of FAO disorders estimated by newborn screening in the Chinese population in Taiwan is 1 in 20,271 live births. Newborn screening also increases the awareness of FAO disorders and triggers clinical diagnoses of these diseases.

13.
J Exp Med ; 210(1): 85-98, 2013 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-23277454

RESUMO

Poly(ADP-ribose) polymerase 1 (Parp1) catalyzes poly(ADP-ribosylation) (PARylation) and induces replication networks involved in multiple nuclear events. Using mass spectrometry and Western blotting, Parp1 and PARylation activity were intensively detected in induced pluripotent stem cells (iPSCs) and embryonic stem cells, but they were lower in mouse embryonic fibroblasts (MEFs) and differentiated cells. We show that knockdown of Parp1 and pharmacological inhibition of PARylation both reduced the efficiency of iPSC generation induced by Oct4/Sox2/Klf4/c-Myc. Furthermore, Parp1 is able to replace Klf4 or c-Myc to enhance the efficiency of iPSC generation. In addition, mouse iPSCs generated from Oct4/Sox2/Parp1-overexpressing MEFs formed chimeric offspring. Notably, the endogenous Parp1 and PARylation activity was enhanced by overexpression of c-Myc and repressed by c-Myc knockdown. A chromatin immunoprecipitation assay revealed a direct interaction of c-Myc with the Parp1 promoter. PAR-resin pulldown, followed by proteomic analysis, demonstrated high levels of PARylated Chd1L, DNA ligase III, SSrp1, Xrcc-6/Ku70, and Parp2 in pluripotent cells, which decreased during the differentiation process. These data show that the activation of Parp1, partly regulated by endogenous c-Myc, effectively promotes iPSC production and helps to maintain a pluripotent state by posttranslationally modulating protein PARylation.


Assuntos
Reprogramação Celular , Genes myc , Células-Tronco Pluripotentes Induzidas/fisiologia , Poli(ADP-Ribose) Polimerases/metabolismo , Animais , Antígenos Nucleares/metabolismo , Diferenciação Celular , Células Cultivadas , Quimera , DNA Ligase Dependente de ATP , DNA Ligases/metabolismo , Proteínas de Ligação a DNA/metabolismo , Fibroblastos/citologia , Fibroblastos/metabolismo , Técnicas de Silenciamento de Genes , Proteínas de Grupo de Alta Mobilidade/metabolismo , Células-Tronco Pluripotentes Induzidas/citologia , Fator 4 Semelhante a Kruppel , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Autoantígeno Ku , Camundongos , Camundongos Endogâmicos C57BL , Fator 3 de Transcrição de Octâmero/genética , Fator 3 de Transcrição de Octâmero/metabolismo , Poli(ADP-Ribose) Polimerase-1 , Poli(ADP-Ribose) Polimerases/genética , Proteínas de Ligação a Poli-ADP-Ribose , Regiões Promotoras Genéticas , Fatores de Transcrição SOXB1/genética , Fatores de Transcrição SOXB1/metabolismo , Proteínas de Xenopus
14.
Cell Transplant ; 22(4): 741-53, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23127968

RESUMO

Glioblastoma multiforme (GBM), the most common and aggressive primary brain tumor, is extremely resistant to current treatment paradigms and has a high rate of tumor recurrence. Recent progress in the field of tumor-initiating cells suggests that GBM stem cells (GBMSCs) may be responsible for tumor progression, resistance to treatment, and tumor relapse. Therefore, understanding the biologically significant pathways involved in modulating GBMSC-specific characteristics offers great promise for development of novel therapeutics, which may improve therapeutic efficacy and overcome present drug resistance. In addition, targeting deregulated microRNA (miRNA) has arisen as a new therapeutic strategy in treating malignant gliomas. In GBMSCs, miRNAs regulate a wide variety of tumorigenic processes including cellular proliferation, stemness maintenance, migration/invasion, apoptosis, and tumorigenicity. Nevertheless, the latest progress with GBMSCs and subsequent miRNA profiling is limited by the identification and isolation of GBMSCs. In this review, we thus summarize current markers and known features for isolation as well as the aberrant miRNAs that have been identified in GBM and GBMSCs.


Assuntos
Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Regulação Neoplásica da Expressão Gênica , Glioblastoma/genética , Glioblastoma/patologia , MicroRNAs/genética , Células-Tronco Neoplásicas/metabolismo , Separação Celular , Humanos , MicroRNAs/metabolismo , Células-Tronco Neoplásicas/patologia
15.
Int J Mol Sci ; 13(1): 1209-1224, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22312313

RESUMO

Autophagy is activated by various stresses, including DNA damage, and previous studies of DNA damage-induced autophagy have focused on the response to chemotherapeutic drugs, ionizing radiation, and reactive oxygen species. In this study, we investigated the biological significance of autophagic response to ultraviolet (UV) irradiation in A549 and H1299 cells. Our results indicated that UV induces on-rate autophagic flux in these cells. Autophagy inhibition resulting from the knockdown of beclin-1 and Atg5 reduced cell viability and enhanced apoptosis. Moreover, we found that ATR phosphorylation was accompanied by microtubule-associated protein 1 light chain 3B II (LC3B-II) expression during the early phases following UV irradiation, which is a well-established inducer of ATR. Knocking down ATR further attenuated the reduction in LC3B-II at early stages in response to UV treatment. Despite the potential role of ATR in autophagic response, reduced ATR expression does not affect autophagy induction during late phases (24 and 48 h after UV treatment). The result is consistent with the reduced ATR phosphorylation at the same time points and suggests that autophagic response at this stage is activated via a distinct pathway. In conclusion, this study demonstrated that autophagy acts as a cytoprotective mechanism against UV-induced apoptosis and that autophagy induction accompanied with apoptosis at late stages is independent of ATR activation.


Assuntos
Autofagia/efeitos da radiação , Raios Ultravioleta , Apoptose/efeitos da radiação , Proteínas Reguladoras de Apoptose/antagonistas & inibidores , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Proteínas Mutadas de Ataxia Telangiectasia/antagonistas & inibidores , Proteínas Mutadas de Ataxia Telangiectasia/genética , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Proteína 5 Relacionada à Autofagia , Proteína Beclina-1 , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos da radiação , Humanos , Potencial da Membrana Mitocondrial/efeitos da radiação , Proteínas de Membrana/antagonistas & inibidores , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Proteínas Associadas aos Microtúbulos/antagonistas & inibidores , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Fosforilação/efeitos da radiação , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Fatores de Tempo
16.
Cancer Chemother Pharmacol ; 69(3): 621-33, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21947203

RESUMO

PURPOSE: BO-1051 is an N-mustard derivative that is conjugated with DNA-affinic 9-anilinoacridine. Since BO-1051 was reported to have strong anticancer activity, we investigated the effect and underlying mechanism of BO-1051 in human glioma cell lines. METHODS: Human glioma cell lines U251MG and U87MG were studied with BO-1051 or the combination of BO-1051 and autophagic inhibitors. Growth inhibition was assessed by MTT assay. Apoptosis was measured by annexin V staining followed by flow cytometry and immunoblotting for apoptosis-related molecules. Induction of autophagy was detected by acridine orange labeling, electron microscopy, LC3 localization and its conversion. Transfection of shRNA was used to determine the involvement of Beclin1 in apoptotic cell death. RESULTS: MTT assay showed that BO-1051 suppressed the viability of four glioma cell lines (U251MG, U87MG, GBM-3 and DBTRG-05MG) in a dose-dependent manner. The IC(50) values of BO-1051 for the glioma cells were significantly lower than the values for primary neurons cultures and normal fibroblast cells. Moreover, BO-1051 not only induced apoptotic cell death, but also enhanced autophagic flux via inhibition of Akt/mTOR and activation of Erk1/2. Importantly, suppression of autophagy by 3-methyladenine or bafilomycin A1 significantly increased BO-1051-induced apoptotic cell death in U251MG and U87MG cells. In addition, the proportion of apoptotic cells after BO-1051 treatment was enhanced by co-treatment with shRNA against Beclin1. CONCLUSIONS: BO-1051 induced both apoptosis and autophagy, and inhibition of autophagy significantly augmented the cytotoxic effect of BO-1051. Thus, a combination of BO-1051 and autophagic inhibitors offers a potentially new therapeutic modality for the treatment of malignant glioma.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Neoplasias Encefálicas/patologia , Glioma/patologia , Compostos de Mostarda Nitrogenada/farmacologia , Antineoplásicos/química , Western Blotting , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/metabolismo , Técnicas de Cultura de Células , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Glioma/tratamento farmacológico , Glioma/metabolismo , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Microscopia Eletrônica de Transmissão , Microscopia de Fluorescência , Microscopia de Contraste de Fase , Estrutura Molecular , Compostos de Mostarda Nitrogenada/química , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Serina-Treonina Quinases TOR/antagonistas & inibidores
17.
J Nutr Biochem ; 23(5): 458-68, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-21684136

RESUMO

BACKGROUND: Atherosclerosis is a chronic inflammatory disease of the vessel wall associated with oxidized low-density lipoprotein (oxLDL)-induced apoptosis of endothelial cells. Coenzyme Q10 (CoQ10), a potent antioxidant and a critical intermediate of the electron transport chain, has been reported to inhibit LDL oxidation and thus the progression of atherosclerosis. However, its molecular mechanisms on endothelial cells remain still unclarified. METHODS: In this study, primary human umbilical vein endothelial cell cultures treated with oxLDL were used to explore the protective effects of CoQ10. RESULTS: Our results showed that CoQ10 attenuated the oxLDL-induced generation of reactive oxygen species and improved the antioxidant capacity. CoQ10 also attenuated the oxLDL-mediated down-regulation of endothelial nitric oxide synthase (eNOS) and up-regulation of inducible nitric oxide synthase (iNOS). In addition, CoQ10 suppressed oxLDL-activated NF-κB and downstream inflammatory mediators, including expression of adhesion molecules, release of proinflammatory cytokines and the adherence of monocytic THP-1 cells. Moreover, CoQ10 attenuated oxLDL-altered proapoptotic responses. The inhibitor of eNOS (L-NIO 10 µM) and iNOS (1400W 10 µM) as well as NO enhancer (SNP 10 µM) were used to clean up the mechanism. CONCLUSION: These results provide new insight into the possible molecular mechanisms by which CoQ10 protects against atherogenesis by NO-related pathways.


Assuntos
Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Óxido Nítrico/metabolismo , Estresse Oxidativo , Transdução de Sinais , Ubiquinona/análogos & derivados , Vitaminas/farmacologia , Apoptose , Dano ao DNA , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Lipoproteínas LDL/metabolismo , NF-kappa B/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Ubiquinona/farmacologia , Regulação para Cima
18.
J Atheroscler Thromb ; 18(11): 966-80, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21817823

RESUMO

AIM: Mesenchymal stem cells (MSCs) are a multipotent cell type that can differentiate into non-hematopoietic cells, such as adipocytes. Adipocyte tissue is central to the regulation of energy balance. Two functionally different types of fat are present in mammals. White adipose tissue is the primary site for triglyceride storage, while brown adipose tissue is specialized in energy expenditure. Peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) controls several aspects of mitochondrial biogenesis. In this study, we hypothesized that PGC-1α plays a role in brown fat differentiation of MSCs. METHODS: Immortalized human MSCs were infected with adenovirus carrying PGC-1α cDNA to create PGC-1α-expressing MSCs. RESULTS: The genetic profiling of PGC-1α-expressing MSCs shows the significant increase of genes related to mitochondrial functions and lipid metabolism compared to that of MSCs. When expressed in MSCs, PGC-1α activates robust mitochondrial biogenesis and respiration. The increase of oxygen consumption and reactive oxygen species represents a cellular readout of increased activity of the respiratory chain. The expression of thermogenic markers, such as cytochrome C and complex II, was significantly increased in MSCs with treatment of adenovirus expressing PGC-1α. Moreover, PGC-1α markedly inhibited the osteogenesis of MSCs under osteogenic induction. During adipogenesis, PGC-1α-expressing MSCs showed a significant increase in brown fat markers and a decrease in white fat markers. Notably, PGC-1α knockdown inhibited adipocyte differentiation of MSCs. CONCLUSIONS: In summary, our data reveal an important role of PGC-1α in promoting brown fat differentiation of MSCs, and provide a new therapeutic approach for the treatment of obesity.


Assuntos
Tecido Adiposo Marrom/citologia , Tecido Adiposo Marrom/metabolismo , Biomarcadores/metabolismo , Diferenciação Celular , Proteínas de Choque Térmico/metabolismo , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Fatores de Transcrição/metabolismo , Adipogenia , Tecido Adiposo Branco/citologia , Tecido Adiposo Branco/metabolismo , Respiração Celular , Metabolismo Energético , Imunofluorescência , Perfilação da Expressão Gênica , Proteínas de Choque Térmico/antagonistas & inibidores , Proteínas de Choque Térmico/genética , Humanos , Proteínas Mitocondriais/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Consumo de Oxigênio , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo , RNA Mensageiro/genética , RNA Interferente Pequeno/genética , Espécies Reativas de Oxigênio/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/genética
19.
Mol Nutr Food Res ; 55 Suppl 2: S227-40, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21812107

RESUMO

SCOPE: The lectin-like oxidized low-density lipoprotein receptor (LOX-1) is one pivot receptor for oxidized low-density lipoprotein (oxLDL) in human endothelial cells. Co-enzyme Q10 (Co Q10) has been widely used in clinical intervention. However, the molecular mechanisms underlying its protective effects against oxidative stress in endothelial cells are still largely unknown. This study was designed to test the hypothesis that Co Q10 mitigates oxLDL-induced endothelial oxidative injuries via modulation of LOX-1-mediated reactive oxygen species (ROS) generation and explored the role of AMP-activated protein kinase (AMPK), a negative regulator of NADPH oxidase. METHODS AND RESULTS: Human umbilical vein endothelial cells (HUVECs) were pretreated with Co Q10 and then incubated with oxLDL for 24 h. Co Q10 attenuated oxLDL-elicited LOX-1 expression and ROS generation by suppression of NADPH oxidase activation. Co Q10 rescued dephosphorylation of AMPK caused by oxLDL that in turn led to an activation of NADPH oxidase by PKC. The results were confirmed using AMPK siRNA. Moreover, oxLDL-suppressed Akt/eNOS and enhanced p38 phosphorylation, which in turn activated NF-κB pathway. These detrimental events were ameliorated by Co Q10. CONCLUSION: These results provide new highlight onto the possible molecular mechanisms of how Q10 suppresses oxLDL-induced endothelial oxidative injuries by the modulation of LOX-1-mediated ROS generation via the AMPK/PKC/NADPH oxidase signaling pathway.


Assuntos
Lipoproteínas LDL/metabolismo , NADPH Oxidases/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Receptores Depuradores Classe E/metabolismo , Ubiquinona/análogos & derivados , Proteínas Quinases Ativadas por AMP/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Membrana Celular/metabolismo , Ativação Enzimática , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , NF-kappa B/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Proteína Quinase C/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Interferente Pequeno , Transdução de Sinais/efeitos dos fármacos , Ubiquinona/farmacologia
20.
Radiat Oncol ; 6: 7, 2011 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-21244709

RESUMO

BACKGROUND: 1-{4-[Bis(2-chloroethyl)amino]phenyl}-3-[2-methyl-5-(4-methylacridin-9-ylamino)phenyl]urea (BO-1051) is an N-mustard DNA alkylating agent reported to exhibit antitumor activity. Here we further investigate the effects of this compound on radiation responses of human gliomas, which are notorious for the high resistance to radiotherapy. METHODS: The clonogenic assay was used to determine the IC50 and radiosensitivity of human glioma cell lines (U87MG, U251MG and GBM-3) following BO-1051. DNA histogram and propidium iodide-Annexin V staining were used to determine the cell cycle distribution and the apoptosis, respectively. DNA damage and repair state were determined by γ-H2AX foci, and mitotic catastrophe was measure using nuclear fragmentation. Xenograft tumors were measured with a caliper, and the survival rate was determined using Kaplan-Meier method. RESULTS: BO-1051 inhibited growth of human gliomas in a dose- and time-dependent manner. Using the dosage at IC50, BO-1051 significantly enhanced radiosensitivity to different extents [The sensitizer enhancement ratio was between 1.24 and 1.50 at 10% of survival fraction]. The radiosensitive G2/M population was raised by BO-1051, whereas apoptosis and mitotic catastrophe were not affected. γ-H2AX foci was greatly increased and sustained by combined BO-1051 and γ-rays, suggested that DNA damage or repair capacity was impaired during treatment. In vivo studies further demonstrated that BO-1051 enhanced the radiotherapeutic effects on GBM-3-beared xenograft tumors, by which the sensitizer enhancement ratio was 1.97. The survival rate of treated mice was also increased accordingly. CONCLUSIONS: These results indicate that BO-1051 can effectively enhance glioma cell radiosensitivity in vitro and in vivo. It suggests that BO-1051 is a potent radiosensitizer for treating human glioma cells.


Assuntos
Neoplasias Encefálicas/radioterapia , Glioblastoma/radioterapia , Compostos de Mostarda Nitrogenada/farmacologia , Tolerância a Radiação/efeitos dos fármacos , Animais , Antineoplásicos Alquilantes/farmacologia , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Dano ao DNA/efeitos dos fármacos , DNA de Neoplasias/efeitos dos fármacos , DNA de Neoplasias/efeitos da radiação , Relação Dose-Resposta a Droga , Feminino , Glioblastoma/genética , Glioblastoma/patologia , Humanos , Camundongos , Camundongos Nus , Modelos Biológicos , Radiossensibilizantes/farmacologia , Regulação para Cima/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
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