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1.
J Environ Sci (China) ; 122: 62-71, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35717091

RESUMO

Antibiotic resistance is a sword of Damocles that hangs over humans. In regards to airborne antibiotic resistance genes (AARGs), critical knowledge gaps still exist in the identification of hotspots and quantification of exposure levels in different environments. Here, we have studied the profiles of AARGs, mobile genetic elements (MGEs) and bacterial communities in various atmospheric environments by high throughput qPCR and 16S rRNA gene sequencing. We propose a new AARGs exposure dose calculation that uses short-term inhalation (STI). Swine farms and hospitals were high-risk areas where AARGs standardised abundance was more abundant than suburbs and urban areas. Additionally, resistance gene abundance in swine farm worker sputum was higher than that in healthy individuals in other environments. The correlation between AARGs with MGEs and bacteria was strong in suburbs but weak in livestock farms and hospitals. STI exposure analysis revealed that occupational intake of AARGs (via PM10) in swine farms and hospitals were 110 and 29 times higher than in suburbs, were 1.5 × 104, 5.6 × 104 and 5.1 × 102 copies, i.e., 61.9%, 75.1% and 10.7% of the overall daily inhalation intake, respectively. Our study comprehensively compares environmental differences in AARGs to identify high-risk areas, and forwardly proposes the STI exposure dose of AARGs to guide risk assessment.


Assuntos
Antibacterianos , Genes Bacterianos , Animais , Antibacterianos/análise , Bactérias/genética , Resistência Microbiana a Medicamentos/genética , Exposição por Inalação , RNA Ribossômico 16S/genética , Suínos
2.
J Environ Sci (China) ; 103: 12-19, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33743895

RESUMO

Antibiotic resistance genes (ARGs) as emergence contaminations have spread widely in the water environment. Wild fish may be recipients and communicators of ARGs in the water environment, however, the distribution and transmission of ARGs in the wild fish and relevant water environment were rarely reported. Here, we have profiled ARGs and bacterial communities in wild freshwater fish and relevant water in a peri-urban river using high-throughput qPCR and 16S rRNA gene sequence. A total of 80 and 220 unique ARG subtypes were identified in fish and water samples. Fish and water both showed significant ARG seasonal variations (P < 0.05). The highest absolute abundance of ARGs in fish and water occurred in summer (1.32 × 109 copies per g, on average) and autumn (9.04 × 106 copies per mL), respectively. In addition, the bipartite network analysis showed that 9 ARGs and 1 mobile genetic element continuously shared in fish and water. Furthermore, bacteria shared in fish and water were found to significantly correlate with shard ARGs. The findings demonstrate that bacteria and ARGs in fish and water could interconnect and ARGs might transfer between fish and water using bacteria as a spreading medium.


Assuntos
Microbioma Gastrointestinal , Rios , Animais , Antibacterianos/análise , Resistência Microbiana a Medicamentos/genética , Genes Bacterianos , RNA Ribossômico 16S/genética , Água
4.
Br J Cancer ; 116(10): 1302-1311, 2017 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-28359080

RESUMO

BACKGROUND: We previously showed that activation of the nuclear factor of activated T cells (NFAT)1/Fas ligand (FasL) pathway induces glioma cell death. Lithium (Li) is an inhibitor of glycogen synthase kinase (GSK)-3 that activates NFAT1/FasL signalling. Temozolomide (TMZ) inhibits GSK-3 and activates Fas in tumour protein (TP)53 wild-type (TP53wt) glioma cells. The present study investigated the combinational effects of TMZ and low-dose Li on TP53wt glioma cells. METHODS: The combined effect of TMZ and Li was examined in TP53wt U87 and primary glioma cells and a mouse xenograft model. RESULTS: Combination with 1.2 mM Li potentiated TMZ-induced cell death in TP53wt glioma cells, as determined by neurosphere formation and apoptosis assays. Temozolomide combined with Li treatment inhibited GSK-3 activation, promoted NFAT1 nuclear translocation and upregulated Fas/FasL expression. Targeted knockdown of NFAT1 expression blocked the induction of cell death by TMZ and Li via FasL inhibition. In vivo, combined treatment with TMZ and Li suppressed tumour growth and prolonged the survival of tumour-bearing mice. However, the combination of TMZ and Li did not produce a statistically significant effect in TP53mut glioma cells. CONCLUSIONS: Temozolomide combined with low-dose Li induces TP53wt glioma cell death via NFAT1/FasL signalling. This represents a potential therapeutic strategy for TP53wt glioma treatment.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/metabolismo , Proteína Ligante Fas/metabolismo , Glioblastoma/tratamento farmacológico , Glioblastoma/metabolismo , Fatores de Transcrição NFATC/metabolismo , Proteína Supressora de Tumor p53/genética , Idoso , Animais , Anticorpos Neutralizantes/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Apoptose/efeitos dos fármacos , Neoplasias Encefálicas/genética , Linhagem Celular Tumoral , Dacarbazina/administração & dosagem , Dacarbazina/análogos & derivados , Proteína Ligante Fas/imunologia , Feminino , Técnicas de Silenciamento de Genes , Glioblastoma/genética , Quinase 3 da Glicogênio Sintase/antagonistas & inibidores , Humanos , Lítio/administração & dosagem , Masculino , Camundongos , Pessoa de Meia-Idade , Fatores de Transcrição NFATC/genética , Transplante de Neoplasias , Cultura Primária de Células , Transporte Proteico/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Taxa de Sobrevida , Temozolomida
5.
Sci Total Environ ; 946: 174201, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38936709

RESUMO

Perfluorinated and perfluoroalkyl substances (PFASs), encompassing a vast array of isomeric chemicals, are recognized as typical emerging contaminants with direct or potential impacts on human health and the ecological environment. With the complex and elusive toxicological profiles of PFASs, machine learning (ML) has been increasingly employed in their toxicity studies due to its proficiency in prediction and data analytics. This integration is poised to become a predominant trend in environmental toxicology, propelled by the swift advancements in computational technology. This review diligently examines the literature to encapsulate the varied objectives of employing ML in the toxicity studies of PFASs: (1) Utilizing ML to establish Quantitative Structure-Activity Relationship (QSAR) models for PFASs with diverse toxicity endpoints, facilitating the targeted toxicity prediction of unidentified PFASs; (2) Investigating and substantiating the Adverse Outcome Pathway (AOP) through the synergy of ML and traditional toxicological methods, with this refining the toxicity assessment framework for PFASs; (3) Dissecting and elucidating the features of established ML models to advance Open Research into the toxicity of PFASs, with a primary focus on determinants and mechanisms. The discourse extends to an in-depth examination of ML studies, segregating findings based on their distinct application trajectories. Given that ML represents a nascent paradigm within PFASs research, this review delineates the collective challenges encountered in the ML-mediated study of PFAS toxicity and proffers strategic guidance for ensuing investigations.

6.
IEEE Trans Pattern Anal Mach Intell ; 45(1): 1294-1301, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35344484

RESUMO

Extracting building footprints from aerial images is essential for precise urban mapping with photogrammetric computer vision technologies. Existing approaches mainly assume that the roof and footprint of a building are well overlapped, which may not hold in off-nadir aerial images as there is often a big offset between them. In this paper, we propose an offset vector learning scheme, which turns the building footprint extraction problem in off-nadir images into an instance-level joint prediction problem of the building roof and its corresponding "roof to footprint" offset vector. Thus the footprint can be estimated by translating the predicted roof mask according to the predicted offset vector. We further propose a simple but effective feature-level offset augmentation module, which can significantly refine the offset vector prediction by introducing little extra cost. Moreover, a new dataset, Buildings in Off-Nadir Aerial Images (BONAI), is created and released in this paper. It contains 268,958 building instances across 3,300 aerial images with fully annotated instance-level roof, footprint, and corresponding offset vector for each building. Experiments on the BONAI dataset demonstrate that our method achieves the state-of-the-art, outperforming other competitors by 3.37 to 7.39 points in F1-score. The codes, datasets, and trained models are available at https://github.com/jwwangchn/BONAI.git.

7.
Water Res ; 231: 119614, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36682238

RESUMO

Hospital wastewater treatment system (HWTS) is an important source and environmental reservoir of clinically relevant antibiotic resistance genes (ARGs). However, how antibiotic resistome of clinical wastewater changed in HWTS is poorly understood. Herein, the basic quantitative traits (i.e., diversity and abundance) of ARGs in three HWTSs were profiled by metagenomics. In total, 709 ARG subtypes belonging to 20 ARG types were detected with relative abundance ranging from 1.12 × 10-5 to 7.33 × 10-1 copies/cell. Notably, most ARGs could not be significantly removed by chlorination treatment in the HWTS. These ARGs were identified to confer resistance to almost all major classes of antibiotics and include ARGs of last-resort antibiotics, such as blaNDM, mcr and tet(X) which were abundantly occurred in HWTS with 19, 5 and 7 variants, respectively. Moreover, qualitative analysis based on metagenome-assembled genome (MAG) analysis revealed that the putative hosts of the identified ARGs were broadly distributed into at least 8 dominant bacterial phyla. Of the 107 ARG-carrying MAGs recovered, 39 encoded multi-antibiotic resistance and 16 belonged to antibiotic resistant pathogens. Further analysis of co-occurrence patterns of ARGs with mobile genetic elements suggested their potential mobility. These key qualitative traits of ARGs provided further information about their phylogeny and genetic context. This study sheds light on the key traits of ARGs associated with resistance dissemination and pathogenicity and health risks of clinical wastewater.


Assuntos
Antibacterianos , Purificação da Água , Antibacterianos/farmacologia , Águas Residuárias , Genes Bacterianos , Hospitais
8.
J Hazard Mater ; 423(Pt B): 127228, 2022 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-34547689

RESUMO

The occurrence of viable but non-culturable (VBNC) bacteria in the wastewater system poses a huge threat to environmental and public health, in particular in hospital wastewater treatment system (HWTS). HWTS-oriented studies have been conducted to assess the effectiveness of chlorination and UV disinfection using indigenous bacteria. Results revealed that the VBNC Escherichia coli and ARGs remained persistent even at high chlorination (12 mg/L for 2.5 h) and UV doses (1000 mJ/cm2). The molecular mechanisms underlying chlorination-/UV-induced VBNC state in E. coli were explored through the transcriptomics and results suggested that most energy-dependent physiological activities (e.g., metabolism) have been suppressed in VBNC E. coli, while the pathogenicity-related genes varied insignificantly compared to the culturable cells, indicating that the VBNC E. coli could potentially display pathogenicity. Further Galleria mellonella model experiment has confirmed that although the disinfection-induced VBNC state made cells less infectious, these cells could regain their pathogenicity after resuscitation. This in vitro study can be used as a reference for studies on infections from VBNC bacteria and highlights the health risk due to VBNC pathogens in hospital effluents. There is a need to develop effluent standards specifically for healthcare facilities, and a stricter downstream disinfection strategy should be considered for the removal of VBNC cells and ARGs in the effluent.


Assuntos
Desinfecção , Escherichia coli , Cloro , Halogenação , Hospitais , Águas Residuárias
9.
Sci Total Environ ; 821: 153367, 2022 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-35085630

RESUMO

The significant rise in the number of antibiotic resistance genes (ARGs) that resulted from our abuse of antibiotics could do severe harm to public health as well as to the environment. We investigated removal efficiency and removal mechanism of electrochemical (EC) treatment based on 6 different bacteria isolated from hospital wastewater carrying 3 last resort ARGs including NDM-1, mcr-1 and tetX respectively. We found that the removal efficiency of ARGs increased with the increase of both voltage and electrolysis time while the maximum removal efficiency can reach 90%. The optimal treatment voltage and treatment time were 3 V and 120 min, respectively. Temperature, pH and other factors had little influence on the EC treatment process. The mechanism of EC treatment was explored from the macroscopic and microscopic levels by scanning electron microscopy (SEM) and flow cytometry. Our results showed that EC treatment significantly changed the permeability of cell membrane and caused cells successively experience early cell apoptosis, late cell apoptosis and cell necrosis. Moreover, compared with traditional disinfection methods, EC treatment had less potential risks. The conjugative transfer frequencies of cells were significantly reduced after treatment. Less than 1% of bacteria entered the viable but nonculturable (VBNC) state and less than 5% of intracellular ARGs (iARGs) turned into extracellular ARGs (eARGs). Our findings provide new insights into as well as important reference for future electrochemical treatment in removing ARB from hospital wastewater.


Assuntos
Antagonistas de Receptores de Angiotensina , Antibacterianos , Inibidores da Enzima Conversora de Angiotensina , Antibacterianos/farmacologia , Bactérias/genética , Resistência Microbiana a Medicamentos/genética , Genes Bacterianos , Águas Residuárias
10.
Sci Total Environ ; 794: 148693, 2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34214804

RESUMO

Swimming pools are crowd-gathering places that are associated with numerous outbreaks of water-borne diseases. Herein, we investigated the distribution of antibiotic resistance genes (ARGs) and bacterial communities in swimming pools and determined the influencing factors and potential human exposure. Sixteen swimming pools with different bather loads (0.01-0.16 person/m2·h) were investigated. Water samples were collected, before opening and after closing of the facilities, from six swimming pools, and skin samples were collected from volunteers. Comprehensive approaches, high-throughput qPCR and 16S rRNA gene sequencing, were used. The results showed that swimming pools contained a higher relative abundance (0.62 gene copies/16S rRNA) and absolute abundance (6.57×108 gene copies/L) of ARGs on average. Bather loads contributed to the increase of core ARGs, and the absolute abundance of ARGs significantly increased by 1.47-1.94 orders of magnitude when the bather load was more than 0.1 person/m2·h. Dermal contact was estimated as the main exposure route of ARGs. Eighteen ARGs that were not detected before swimming were found on human skin and remained after showering. Furthermore, the event intake burden of ARGs via dermal contact was higher than that via ingestion when swimming. This study provides an assessment of ARGs and antibiotic-resistant bacteria (ARB) in swimming pools and helps to define the health risks to swimmers.


Assuntos
Antibacterianos , Piscinas , Antagonistas de Receptores de Angiotensina , Inibidores da Enzima Conversora de Angiotensina , Antibacterianos/farmacologia , Resistência Microbiana a Medicamentos , Genes Bacterianos , Humanos , RNA Ribossômico 16S/genética
11.
Sci Total Environ ; 771: 144814, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33540158

RESUMO

Wastewater treatment plants (WWTPs) in China have been upgraded or renovated with a variety of emerging processes, but a comprehensive understanding of the behavior of antibiotic resistance genes (ARGs) in these WWTPs is still lacking. Here, the distribution of ARGs and bacterial community were investigated in a wastewater treatment plant with upgrading processes (WWTP-UP). 238 unique ARGs were detected in all samples. During the study period, the average ARGs concentration decreased by 98.4% along the entire treatment process. The removal efficiency of A2/O-membrane bioreactor (MBR) process was significantly higher than that of A2/O-high efficiency flocculent settling/cloth media filter (HEFS/CMF) process (p < 0.05), which corresponded to 3.5 and 2.1 log values on average, respectively. Notably, 35 ARGs and 14 mobile genetic elements (MGEs) were persistent in all samples. Based on the co-occurrence pattern revealed by network analysis, persistent ARGs possibly spread through the transfer of persistent MGEs among persistent bacteria. Using multiple linear regression analysis, we obtained 3 to 5 possible indicators for major ARG types, which might be served to evaluate the general distribution of ARGs or even predict the abundance of different ARG types. Our findings provide new insights into the impacts of upgrading process on ARGs and highlight the need for better strategies to improve ARGs elimination in WWTPs.


Assuntos
Antibacterianos , Purificação da Água , Antibacterianos/farmacologia , China , Resistência Microbiana a Medicamentos/genética , Genes Bacterianos , Águas Residuárias
12.
Water Res ; 209: 117907, 2021 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-34864622

RESUMO

Hospital wastewater contains abundant antibiotics, antibiotic resistance genes (ARGs), and pathogens. Last-resort antibiotic resistance genes (LARGs) include the New Delhi metallo-ß-lactamase gene blaNDM, mobile colistin resistance gene mcr and tigecycline resistance gene tet(X) which confers resistance to carbapenems, colistin and tigecycline. The presence and significance of LARGs in hospital wastewater treatment systems (HWTS) have not yet been systematically explored. Here, LARG variants were shown to be prevalent both influents and effluents of HWTS. A total of 989 Enterobacteriaceae isolates that confer resistance to last-resort antibiotics were collected from effluents and multiple genetic contexts of LARGs were analyzed. LARGs-carrying plasmids were confirmed to show high multidrug phenotypes and transferability. We also discovered the co-occurrence of plasmids harboring blaNDM-1 and mcr-1 in single Escherichia coli, as well as E. coli HM016 containing two unique mcr-1-carrying plasmids. This result might accelerate co-dissemination of LARGs under environmental selection pressure. Different core genetic arrangements in these strains suggest several evolutionary pathways in HWTS. The resistance functions of LARGs were confirmed in vitro and in vivo by mass spectrometry. This study provides novel insights into the diversity, genetic context and function of critical ARGs in HWTS. The results raise the concern that LARGs may further spread into the environment, thus, more stringent discharge standards and regulations for hospital wastewater are urgently needed.

13.
Environ Int ; 153: 106501, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33836339

RESUMO

Antimicrobial resistance is an increasingly serious threat to public health worldwide. The presence of antibiotic resistance genes (ARGs) in human airways and relevant environments has not received significant attention. In this study, abundances of ARGs and microbes from airborne particulate matter, dust, and human airways in a hospital were profiled using high-throughput qPCR and 16S rRNA gene sequencing. More diverse ARGs and microbes in indoor dust and higher levels of ARGs in particulate matter PM10 and PM2.5 were observed. Macrolides and aminoglycoside resistance genes were the most abundant ARGs in the airway and environmental samples, respectively. Moreover, the co-occurrences of priority pathogens, ARGs, and mobile genetic elements (MGEs) were shown by the Network analysis. Campylobacter spp. and Staphylococcus spp. positively correlated with fluoroquinolone (vatC-02, mexD) and ß-lactams (blaZ, mecA) resistance genes, respectively. In this regard, based on SourceTracker analysis, inhalable particles contributed to 4.0% to 5.5% of ARGs in human airway samples, suggesting an important exchange between airborne inhalable particles and human commensals. This study may advance knowledge about ARGs in airborne particulate matter and dust associated environments, reveal their potential link between environments and humans, and provide a new sight and fundamental data for ARG risk assessment.


Assuntos
Antibacterianos , Microbiota , Antibacterianos/farmacologia , Resistência Microbiana a Medicamentos/genética , Poeira , Genes Bacterianos , Hospitais Urbanos , Humanos , Microbiota/genética , Material Particulado/toxicidade , RNA Ribossômico 16S/genética
14.
Environ Sci Pollut Res Int ; 28(29): 38706-38717, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33742379

RESUMO

Abuse of antibiotics in aquaculture have been alarming and might aggravate spread of resistance genes in the environment. Holistic ARGs proliferation checks require deeper analyses of coupled absolute abundances in 16S rRNA bacteria communities at the phylum level to detect biomarkers. Sulfanilamide (sul) and copper II sulfate (CuSO4 II) were, therefore, designed and added as separate or combined treatments in 9 replicate engineered goldfish tanks comprising 3 individual sul, 3 CuSO4 II, 3 (sul + CuSO4 II) combinations, and 3 controls within 180 days. The DNA from water and fish guts was sequenced under qPCR to determine 16S rRNA bacteria biomarkers co-occurring with the correspondent ARGs. Combined chemical addition at 0.8-1.5 mg sul + 0.5-1.0 mg CuSO4 II/3 L of tank waters reduced sequenced 16S rRNA bacteria absolute abundances in fish gut and water samples while portraying the biomarkers. Absolute abundances of the entire 16S rRNA bacteria was higher in fish guts (3.4 × 1014-4.9 × 108 copies/g) than water samples (1.5 × 109-2.6 × 1015 copies/L), respectively. Much as sul 1(log) were dominant over intl 1(log) genes, and their fundamental profiles were also higher in the fish guts than water samples; the Spearman's correlation analyses revealed positive relationship (p < 0.01 and r = 0.873) among the biomarkers of both ARG pairs at the phylum level and the physicochemical parameters. In the fish gut and water samples ratios, Bacteroidetes (10-85:12-85%) > Proteobacteria (10-50:15-65%) > Planktomycetes (10-52:8-25%) featured prominently based on LEfSe use as the hot-spotted biomarkers, hence justifying its higher prospects towards innovative environmental microbiological and biotechnological studies.


Assuntos
Cobre , Genes Bacterianos , Animais , Antibacterianos , Bactérias/genética , Resistência Microbiana a Medicamentos , Carpa Dourada , RNA Ribossômico 16S/genética , Sulfanilamida
15.
Guang Pu Xue Yu Guang Pu Fen Xi ; 30(6): 1674-7, 2010 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-20707174

RESUMO

In order to make clear the changes in the micro crystal structures of celluloses and the functional group of main components including cellulose, hemicelluloses and lignin in wood decayed by fungi, the crystallinity, layer spacing d in crystalline unit cell, width of crystallite and functional group of main components of Populus tomentosa Carr wood, which was decayed by Phanerochaete Chysosporium (white-rot) and Postia Placenta (brown-rot) with various durations, for two weeks, four weeks, six weeks, eight weeks and ten weeks, respectively, were investigated by means of X-ray diffraction and FTIR spectroscopy methods. It was concluded that the lattice structures of crystallite in wood cellulose were not destroyed by PC and PP, and the two theta angles and layer spacing d in crystallite were constant, although the decaying treatment times were different for each other when decayed by the same fungi. However, the crystallinity and width of crystallite decreased with the decaying treatment times increasing, and the decaying effects by PP were more significantly than those by PC, which showed that the damage extent of celluloses decayed by PP was greater than that by PC. It was estimated that the xylan in hemicelluloses had been degraded to various extents with the process of decaying in wood, resulting in the carbonyl content increasing, and the effects of degradation on hemicelluloses and celluloses by PC and PP were almost the same. Furthermore, benzene rings in lignin, which had no remarkable changes by PP, were oxidized into chain hydrocarbon after decaying by PC.


Assuntos
Fungos , Espectroscopia de Infravermelho com Transformada de Fourier , Madeira/análise , Difração de Raios X , Celulose/química , Lignina/química , Polissacarídeos/química , Populus/química
16.
PLoS One ; 9(4): e93791, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24690948

RESUMO

It has been found that preoperative plasma IGFBP-2 levels correlate with prognosis in glioma patients. The prognostic value of plasma IGFBP-2 after postoperative combined radiotherapy and chemotherapy in glioma patients is unknown. Plasma IGFBP-2 levels in 83 glioblastoma patients after postoperative radiotherapy plus chemotherapy were analyzed using an IGFBP-2 ELISA kit. We found that after standard therapy plasma IGFBP-2 levels significantly correlated with the patient's age (R = 0.738, P<0.001) and Karnofsky performance status (KPS, R =  -0.633, P<0.05). Cox proportional hazards models were used to calculate hazard ratios (HRs) of death according to plasma IGFBP-2 levels adjusted for patient clinical characteristics. Plasma IGFBP-2 levels significantly correlated with overall survival in glioblastoma patients (multivariate HR = 1.035; 95% CI, 1.024-1.047; P<0.001). The effect of plasma IGFBP-2 levels on survival seemed to differ according to patients' age. Among patients older than 60, high plasma IGFBP-2 levels were associated with a significant increase in overall mortality (HR = 1.097; 95% CI, 1.055-1.140; P<0.001). In contrast, plasma IGFBP-2 levels conferred no significant effect on mortality among patients younger than 60. Elevated plasma IGFBP-2 levels after combined postoperative radiotherapy and chemotherapy in elderly glioblastoma patients correlate with poor KPS score and predicts poor prognosis.


Assuntos
Biomarcadores Tumorais/sangue , Glioblastoma/sangue , Glioblastoma/tratamento farmacológico , Glioblastoma/radioterapia , Proteína 2 de Ligação a Fator de Crescimento Semelhante à Insulina/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Terapia Combinada , Feminino , Glioblastoma/patologia , Glioblastoma/cirurgia , Humanos , Avaliação de Estado de Karnofsky , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Prognóstico , Modelos de Riscos Proporcionais , Análise de Sobrevida
17.
PLoS One ; 9(6): e100297, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24937153

RESUMO

OBJECTIVE: This study explored the effects of telomerase reverse transcriptase (TERT) promoter mutations on transcriptional activity of the TERT gene under hypoxic and temozolomide (TMZ) treatment conditions, and investigated the status and prognostic value of these mutations in gliomas. METHODS: The effect of TERT promoter mutations on the transcriptional activity of the TERT gene under hypoxic and TMZ treatment conditions was investigated in glioma cells using the luciferase assay. TERT promoter mutations were detected in 101 glioma samples (grades I-IV) and 49 other brain tumors by sequencing. TERT mRNA expression in gliomas was examined by real-time PCR. Hazard ratios from survival analysis of glioma patients were determined relative to the presence of TERT promoter mutations. RESULTS: Mutations in the TERT promoter enhanced gene transcription even under hypoxic and TMZ treatment conditions, inducing upregulation of TERT mRNA expression. Mutations were detected in gliomas, but not in meningiomas, pituitary adenomas, cavernomas, intracranial metastases, normal brain tissues, or peripheral blood of glioma patients. Patients with TERT promoter mutations had lower survival rates, even after adjusting for other known or potential risk factors, and the incidence of mutation was correlated with patient age. CONCLUSION: TERT promoter mutations were specific to gliomas. TERT promoter mutations maintained its ability of inducing high transcriptional activity even under hypoxic and TMZ treatment conditions, and the presence of mutations was associated with poor prognosis in glioma patients. These findings demonstrate that TERT promoter mutations are novel prognostic markers for gliomas that can inform prospective therapeutic strategies.


Assuntos
Dacarbazina/análogos & derivados , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioma/tratamento farmacológico , Hipóxia/fisiopatologia , Mutação/genética , Regiões Promotoras Genéticas/genética , Telomerase/genética , Antineoplásicos Alquilantes/farmacologia , Biomarcadores Tumorais/genética , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/secundário , Dacarbazina/farmacologia , Feminino , Seguimentos , Glioma/genética , Glioma/mortalidade , Glioma/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Taxa de Sobrevida , Temozolomida
18.
PLoS One ; 8(10): e76717, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24130787

RESUMO

Phorbol myristate acetate (PMA) and ionomycin (Io) can induce T cell activation and proliferation. Furthermore, they stimulate activation-induced cell death (AICD) in mature lymphocytes via Fas/Fas ligand (FasL) up-regulation. In this study, we explored the influence of PMA/Io treatment on glioblastoma cells, and found that AICD-like phenomena may also occur in glioma. Using the MTT assay and cell counting, we demonstrated that treatment of PMA/Io significantly inhibited the proliferation of glioma cell lines, U87 and U251. TUNEL assays and transmission electron microscopy revealed that PMA/Io markedly induced U87 and U251 cell apoptosis. Propidium iodide staining and flow cytometry showed that treatment with PMA/Io resulted in an arrestment of cell cycle and an increase in cell death. Using real-time PCR and western blot, we found that PMA/Io up-regulated the expression of Fas and FasL at both mRNA and protein level, which confirmed that PMA/Io induced glioma cell death. Specific knockdown of NFAT1 expression by small hairpin RNA greatly reduced the PMA/Io induced cell death and apoptosis by inhibition of FasL expression. Microarray analysis showed that the expression of NFAT1 significantly correlated with the expression of Fas. The coexistence of Fas with NFAT1 in vivo provides the background for AICD-like phenomena to occur in glioma. These findings demonstrate that PMA/Io can induce glioblastoma cell death through the NFAT1-Fas/FasL pathway. Glioma-related AICD-like phenomena may provide a novel avenue for glioma treatment.


Assuntos
Apoptose/efeitos dos fármacos , Glioblastoma/patologia , Ionomicina/farmacologia , Acetato de Tetradecanoilforbol/farmacologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Proteína Ligante Fas/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Ativação Linfocitária/efeitos dos fármacos , Fatores de Transcrição NFATC/genética , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Receptor fas/genética
19.
PLoS One ; 8(6): e66008, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23762456

RESUMO

Members of the nuclear factor of activated T cells (NFAT) family have been identified as regulators of oncogenic transformation in several human malignancies. A prominent member of this family, NFAT1, is associated with tumor cell survival, apoptosis, migration and invasion. Here, we investigated the role of NFAT1 in glioma cells. In 111 clinical samples, microarray analysis demonstrated that NFAT1 was over-expressed in glioblastoma multiforme (GBM), compared with low-grade gliomas, a result confirmed by RT-PCR in 24 clinical samples and in the U87 and U251 cell lines. Immunohistochemistry and immunofluorescence stain indicated that over-expressed NFAT1 was mainly located in the nucleus, where it acted as a transcription factor. After treatment with the NFAT antagonist cyclosporin A (CsA) and FK506, levels of NFAT1 in the nuclei of U87 GBM cells were dramatically reduced. The invasive potential of U87 cells was reduced by the same treatment, as well as by inhibition of NFAT1 expression using small hairpin RNA. Proliferation of U87 cells was unaffected by CsA, FK506 and NFAT1 shRNA transfection. Clustering analysis and Pearson correlation analysis of microarray data showed that the expression of NFAT1 correlated with the expression of the invasion-related genes cyclooxygenase-2 (COX-2), matrix metalloproteinase-7 (MMP-7) and MMP-9, a result confirmed by in vitro analysis. These findings demonstrate that NFAT1 contributes to the invasive potential but not the proliferation of GBM cells, and suggest that CsA may find application as an adjuvant in combined treatment strategies for GBM.


Assuntos
Neoplasias Encefálicas/genética , Núcleo Celular/genética , Regulação Neoplásica da Expressão Gênica , Glioblastoma/genética , Fatores de Transcrição NFATC/genética , Biópsia , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Ciclo Celular , Linhagem Celular Tumoral , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Núcleo Celular/patologia , Proliferação de Células , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Ciclosporina/farmacologia , Perfilação da Expressão Gênica , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Metaloproteinase 7 da Matriz/genética , Metaloproteinase 7 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , Fatores de Transcrição NFATC/antagonistas & inibidores , Fatores de Transcrição NFATC/metabolismo , Invasividade Neoplásica , Análise de Sequência com Séries de Oligonucleotídeos , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Tacrolimo/farmacologia
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