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1.
Biochem Biophys Res Commun ; 682: 359-364, 2023 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-37839104

RESUMO

Association between cancer risk and Parkinson's disease is still debated. DJ-1, a Parkinson's disease (PD)-related gene, is encoded by PARK-7 gene and its deficiency causes early-onset PD. In our last studies, it was found that the immunosuppressive microenvironment established in DJ-1 knockout (KO) mice can enhance metastasis of melanoma cells to lungs. Therefore, we wanted to further examine whether there were some niche in other organs of DJ-1-deficiency mouse to facilitate cell growth of tumors. We used in vivo tissue-specific models of tumor growth and in vitro cellular model to verify the hypothesis. We also used protein blot assay, cell-adhesion assay and bioinformatic tools to conduct experiments. In the mouse model of subcutaneous injection, there was no difference on tumor growth between WT and DJ-1 KO mice. Moreover, the results of experimental liver metastasis by intrasplenic injection model showed that there was no difference of nodules number in both mice, but a dramatic enhancement of nodule formation and increased mucin4 levels were found in pancreas of DJ-1 KO mice. In cell cultures, we further found that B16F10 cells indeed tended to adhere well to primary DJ-1-deficiency pancreatic epithelial cells, which had higher protein levels of mucin4. Notably, a human database also showed the inverse relationship in human pancreas between DJ-1 and mucin4, and mucin4 down-regulation can reverse the enhanced cellular adhesion in DJ-1 KO pancreatic epithelial cells. These results indicated that DJ-1 KO pancreatic tissue creating an appropriate microenvironment benefited development of the cancer cells.


Assuntos
Neoplasias , Doença de Parkinson , Animais , Humanos , Camundongos , Pulmão/metabolismo , Camundongos Knockout , Pâncreas/metabolismo , Doença de Parkinson/metabolismo , Proteína Desglicase DJ-1/genética , Microambiente Tumoral
2.
BMC Cancer ; 23(1): 713, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37525108

RESUMO

BACKGROUND: Glioblastoma (GBM), a malignant brain tumor, has poor survival outcomes due to recurrence or drug resistance. We found that SH3GLB1 is a crucial factor for cells to evade temozolomide (TMZ) cytotoxicity through autophagy-mediated oxidative phosphorylation, which is associated with CD133 levels. Therefore, we propose that SH3GLB1 participate in the impact on tumor-initiating cells (TICs). METHODS: The parental, the derived resistant cell lines and their CD133+ cells were used, and the levels of the proteins were compared by western blotting. Then RNA interference was applied to observe the effects of the target protein on TIC-related features. Finally, in vitro transcription assays were used to validate the association between SH3GLB1 and CD133. RESULTS: The CD133+ cells from resistant cells with enhanced SH3GLB1 levels more easily survived cytotoxic treatment than those from the parental cells. Inhibition of SH3GLB1 attenuated frequency and size of spheroid formation, and the levels of CD133 and histone 4 lysine 5 (H4K5) acetylation can be simultaneously regulated by SH3GLB1 modification. The H4K5 acetylation of the CD133 promoter was later suggested to be the mediating mechanism of SH3GLB1. CONCLUSIONS: These data indicate that SH3GLB1 can regulate CD133 expression, suggesting that the protein plays a crucial role in TICs. Our findings on the effects of SH3GLB1 on the cells will help explain tumor resistance formation.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Humanos , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Glioblastoma/metabolismo , Linhagem Celular Tumoral , Temozolomida/farmacologia , Temozolomida/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Interferência de RNA , Resistencia a Medicamentos Antineoplásicos/genética
3.
J Biomed Sci ; 28(1): 18, 2021 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-33685470

RESUMO

Glioblastoma is the most common primary malignant brain tumor that is usually considered fatal even with treatment. This is often a result for tumor to develop resistance. Regarding the standard chemotherapy, the alkylating agent temozolomide is effective in disease control but the recurrence will still occur eventually. The mechanism of the resistance is various, and differs in terms of innate or acquired. To date, aberrations in O6-methylguanine-DNA methyltransferase are the clear factor that determines drug susceptibility. Alterations of the other DNA damage repair genes such as DNA mismatch repair genes are also known to affect the drug effect. Together these genes have roles in the innate resistance, but are not sufficient for explaining the mechanism leading to acquired resistance. Recent identification of specific cellular subsets with features of stem-like cells may have role in this process. The glioma stem-like cells are known for its superior ability in withstanding the drug-induced cytotoxicity, and giving the chance to repopulate the tumor. The mechanism is complicated to administrate cellular protection, such as the enhancing ability against reactive oxygen species and altering energy metabolism, the important steps to survive. In this review, we discuss the possible mechanism for these specific cellular subsets to evade cancer treatment, and the possible impact to the following treatment courses. In addition, we also discuss the possibility that can overcome this obstacle.


Assuntos
Antineoplásicos Alquilantes/farmacologia , Resistencia a Medicamentos Antineoplásicos , Glioblastoma/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Temozolomida/farmacologia , Animais , Glioblastoma/tratamento farmacológico , Humanos
4.
Int J Mol Sci ; 22(20)2021 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-34681918

RESUMO

The phosphoinositide-3-kinase (PI3K) pathway has widely been considered as a potential therapeutic target for head and neck cancer (HNC); however, the application of PI3K inhibitors is often overshadowed by the induction of drug resistance with unknown mechanisms. In this study, PII3K inhibitor resistant cancer cells were developed by prolonged culturing of cell lines with BEZ235, a dual PI3K and mammalian target of rapamycin (mTOR) inhibitor. The drug resistant HNC cells showed higher IC50 of the proliferation to inhibitors specifically targeting PI3K and/or mTOR, as compared to their parental cells. These cells also showed profound resistance to drugs of other classes. Molecular analysis revealed persistent activation of phosphorylated AKT at threonine 308 in the drug resistant cells and increased expression of markers for tumor-initiating cells. Interestingly, increased intra-cellular ROS levels were observed in the drug resistant cells. Among anti-oxidant molecules, the expression of SOD2 was increased and was associated with the ALDH-positive tumor-initiating cell features. Co-incubation of SOD inhibitors and BEZ235 decreased the stemness feature of the cells in vitro, as shown by results of the spheroid formation assay. In conclusion, dysregulation of SOD2 might contribute to the profound resistance to PI3K inhibitors and the other drugs in HNC cells.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Neoplasias de Cabeça e Pescoço/metabolismo , Imidazóis/farmacologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Quinolinas/farmacologia , Superóxido Dismutase/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Resistência a Múltiplos Medicamentos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Humanos , Células-Tronco Neoplásicas/metabolismo , Fosfatidilinositol 3-Quinase/metabolismo , Fosforilação , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima
5.
Microb Ecol ; 80(1): 133-144, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31832698

RESUMO

Miscanthus in Taiwan occupies a cline along altitude and adapts to diverse environments, e.g., habitats of high salinity and volcanoes. Rhizospheric and endophytic bacteria may help Miscanthus acclimate to those stresses. The relative contributions of rhizosphere vs. endosphere compartments to the adaptation remain unknown. Here, we used targeted metagenomics to compare the microbial communities in the rhizosphere and endosphere among ecotypes of M. sinensis that dwell habitats under different stresses. Proteobacteria and Actinobacteria predominated in the endosphere. Diverse phyla constituted the rhizosphere microbiome, including a core microbiome found consistently across habitats. In endosphere, the predominance of the bacteria colonizing from the surrounding soil suggests that soil recruitment must have subsequently determined the endophytic microbiome in Miscanthus roots. In endosphere, the bacterial diversity decreased with the altitude, likely corresponding to rising limitation to microorganisms according to the species-energy theory. Specific endophytes were associated with different environmental stresses, e.g., Pseudomonas spp. for alpine and Agrobacterium spp. for coastal habitats. This suggests Miscanthus actively recruits an endosphere microbiome from the rhizosphere it influences.


Assuntos
Bactérias/isolamento & purificação , Ecótipo , Endófitos , Microbiota , Poaceae/microbiologia , Rizosfera , Bactérias/classificação , Biocombustíveis , Ecossistema , Metagenômica
6.
J Biomed Sci ; 26(1): 77, 2019 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-31629402

RESUMO

BACKGROUND: Intratumor subsets with tumor-initiating features in glioblastoma are likely to survive treatment. Our goal is to identify the key factor in the process by which cells develop temozolomide (TMZ) resistance. METHODS: Resistant cell lines derived from U87MG and A172 were established through long-term co-incubation of TMZ. Primary tumors obtained from patients were maintained as patient-derived xenograft for studies of tumor-initating cell (TIC) features. The cell manifestations were assessed in the gene modulated cells for relevance to drug resistance. RESULTS: Among the mitochondria-related genes in the gene expression databases, superoxide dismutase 2 (SOD2) was a significant factor in resistance and patient survival. SOD2 in the resistant cells functionally determined the cell fate by limiting TMZ-stimulated superoxide reaction and cleavage of caspase-3. Genetic inhibition of the protein led to retrieval of drug effect in mouse study. SOD2 was also associated with the TIC features, which enriched in the resistant cells. The CD133+ specific subsets in the resistant cells exhibited superior superoxide regulation and the SOD2-related caspase-3 reaction. Experiments applying SOD2 modulation showed a positive correlation between the TIC features and the protein expression. Finally, co-treatment with TMZ and the SOD inhibitor sodium diethyldithiocarbamate trihydrate in xenograft mouse models with the TMZ-resistant primary tumor resulted in lower tumor proliferation, longer survival, and less CD133, Bmi-1, and SOD2 expression. CONCLUSION: SOD2 plays crucial roles in the tumor-initiating features that are related to TMZ resistance. Inhibition of the protein is a potential therapeutic strategy that can be used to enhance the effects of chemotherapy.


Assuntos
Antineoplásicos Alquilantes/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Glioblastoma/tratamento farmacológico , Células-Tronco Neoplásicas/efeitos dos fármacos , Superóxido Dismutase/administração & dosagem , Temozolomida/farmacologia , Animais , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Xenoenxertos/fisiopatologia , Humanos , Camundongos , Células-Tronco Neoplásicas/fisiologia
7.
BMC Genomics ; 19(Suppl 2): 85, 2018 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-29764390

RESUMO

BACKGROUND: Transcription factors (TFs) play essential roles during plant development and response to environmental stresses. However, the relationships among transcription factors, cis-acting elements and target gene expression under endo- and exogenous stimuli have not been systematically characterized. RESULTS: Here, we developed a series of bioinformatics analysis methods to infer transcriptional regulation by using numerous gene expression data from abiotic stresses and hormones treatments. After filtering the expression profiles of TF-encoding genes, 291 condition specific transcription factors (CsTFs) were obtained. Differentially expressed genes were then classified into various co-expressed gene groups based on each CsTFs. In the case studies of heat stress and ABA treatment, several known and novel cis-acting elements were identified following our bioinformatics approach. Significantly, a palindromic sequence of heat-responsive elements is recognized, and also obtained from a 3D protein structure of heat-shock protein-DNA complex. Notably, overrepresented 3- and 4-mer motifs in an enriched 8-mer motif could be a core cis-element for a CsTF. In addition, the results suggest DNA binding preferences of the same CsTFs are different according to various conditions. CONCLUSIONS: The overall results illustrate this study may be useful in identifying condition specific cis- and trans- regulatory elements and facilitate our understanding of the relationships among TFs, cis-acting elements and target gene expression.


Assuntos
Arabidopsis/crescimento & desenvolvimento , Biologia Computacional/métodos , Regiões Promotoras Genéticas , Fatores de Transcrição/genética , Ácido Abscísico/farmacologia , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Estresse Fisiológico
8.
Nucleic Acids Res ; 44(D1): D1154-60, 2016 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-26476450

RESUMO

Transcription factors (TFs) are sequence-specific DNA-binding proteins acting as critical regulators of gene expression. The Plant Promoter Analysis Navigator (PlantPAN; http://PlantPAN2.itps.ncku.edu.tw) provides an informative resource for detecting transcription factor binding sites (TFBSs), corresponding TFs, and other important regulatory elements (CpG islands and tandem repeats) in a promoter or a set of plant promoters. Additionally, TFBSs, CpG islands, and tandem repeats in the conserve regions between similar gene promoters are also identified. The current PlantPAN release (version 2.0) contains 16 960 TFs and 1143 TF binding site matrices among 76 plant species. In addition to updating of the annotation information, adding experimentally verified TF matrices, and making improvements in the visualization of transcriptional regulatory networks, several new features and functions are incorporated. These features include: (i) comprehensive curation of TF information (response conditions, target genes, and sequence logos of binding motifs, etc.), (ii) co-expression profiles of TFs and their target genes under various conditions, (iii) protein-protein interactions among TFs and their co-factors, (iv) TF-target networks, and (v) downstream promoter elements. Furthermore, a dynamic transcriptional regulatory network under various conditions is provided in PlantPAN 2.0. The PlantPAN 2.0 is a systematic platform for plant promoter analysis and reconstructing transcriptional regulatory networks.


Assuntos
Bases de Dados Genéticas , Regulação da Expressão Gênica de Plantas , Redes Reguladoras de Genes , Plantas/genética , Regiões Promotoras Genéticas , Sítios de Ligação , Anotação de Sequência Molecular , Proteínas de Plantas/metabolismo , Fatores de Transcrição/metabolismo , Transcrição Gênica
9.
J Med Biol Eng ; 38(5): 835-844, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30220902

RESUMO

The aim of this study was to establish a web-based platform for exchanging medical device management and maintenance experiences to enhance the professional competency of clinical engineers (CEs), which ensures the quality of medical devices and increases patients' satisfaction with medical services. Medical devices play an essential role in diagnosis and disease management. CEs are responsible for providing functional medical devices that contribute worthwhile functions to a medical service to improve patients' health and safety. The purpose of the platform is to facilitate collection and sharing of medical device incidents experiences to improve CEs' capability. To provide useful and practical information for CEs, an event review committee, composed of experts with more than 20 years of clinical engineering experience who were recruited as reviewers, was established under the platform. Cases submitted to the platform were required to have comprehensive descriptions of the device and events. Each case was evaluated by at least two reviewers based on five evaluation indices: (1) severity, (2) breadth, (3) frequency, (4) insidiousness, and (5) correctness. After being reviewed, each final report was published on the platform to be shared with the event submitters and other members. The results show that 116 staffs from 32 different hospitals, registered to join this platform. From January 2015 to December 2016, 70 events were submitted with 56 reports. This study also assessed the platform's benefits for CEs. A total of 93 respondents completed a questionnaire survey: 93% of the CEs agreed that the information from the platform helped them do their job. The web-based platform has high value as an experience-sharing interface for medical devices. The CEs obtained extremely useful information from the platform for medical device management and their daily duties. This study provided an online training model with systematic methods to improve the quality and effectiveness of medical device management.

10.
BMC Cancer ; 16(1): 871, 2016 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-27825319

RESUMO

BACKGROUND: Growth hormone (GH) mainly serves an endocrine function to regulate somatic growth, but also serves an autocrine function in lung growth and pulmonary function. Several recent studies have demonstrated the role of autocrine GH in tumor progression in some organs. However, it is not clear whether excessive secretion of GH in the lungs is related to pulmonary nodule formation. METHODS: Firstly, the lung tissues dissected from mice were used for Western blotting and PCR measurement. Secondly, the cultured cells were used for examining effects of GH on B16F10 murine melanoma cells. Thirdly, male C57BL/6 mice were intravenously injected with B16F10 cells and then subcutaneously injected with recombinant GH twice per week for three weeks. Finally, stably transfected pool of B16F10 cells with knockdown of growth hormone receptor (GHR) was used to be injected into mice. RESULTS: We found that expression of GH was elevated in the lungs of DJ-1 knockout (KO) mice. We also examined the effects of GH on the growth of cultured melanoma cells. The results showed that GH increased proliferation, colony formation, and invasive capacity of B16F10 cells. In addition, GH also increased the expression of matrix metalloproteinases (MMPs) in B16F10 cells. Administration of GH in vivo enhanced lung nodule formation in C57/B6 mice. Increased lung nodule formation in DJ-1 KO mice following intravenous injection of melanoma cells was inhibited by GHR knockdown in B16F10 cells. CONCLUSIONS: These results indicate that up-regulation of GH in the lungs of DJ-1 KO mice may enhance the malignancy of B16F10 cells and nodule formation in pulmonary metastasis of melanoma.


Assuntos
Hormônio do Crescimento/metabolismo , Neoplasias Pulmonares/secundário , Pulmão/metabolismo , Melanoma Experimental/metabolismo , Melanoma Experimental/patologia , Proteína Desglicase DJ-1/deficiência , Animais , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células , Sobrevivência Celular/genética , Modelos Animais de Doenças , Masculino , Metaloproteinases da Matriz/metabolismo , Camundongos , Camundongos Knockout , Nódulo Pulmonar Solitário , Carga Tumoral , Ensaio Tumoral de Célula-Tronco
11.
BMC Genomics ; 16 Suppl 2: S6, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25708775

RESUMO

BACKGROUND: In general, the expression of gene alters conditionally to catalyze a specific metabolic pathway. Microarray-based datasets have been massively produced to monitor gene expression levels in parallel with numerous experimental treatments. Although several studies facilitated the linkage of gene expression data and metabolic pathways, none of them are amassed for plants. Moreover, advanced analysis such as pathways enrichment or how genes express under different conditions is not rendered. DESCRIPTION: Therefore, EXPath was developed to not only comprehensively congregate the public microarray expression data from over 1000 samples in biotic stress, abiotic stress, and hormone secretion but also allow the usage of this abundant resource for coexpression analysis and differentially expression genes (DEGs) identification, finally inferring the enriched KEGG pathways and gene ontology (GO) terms of three model plants: Arabidopsis thaliana, Oryza sativa, and Zea mays. Users can access the gene expression patterns of interest under various conditions via five main functions (Gene Search, Pathway Search, DEGs Search, Pathways/GO Enrichment, and Coexpression analysis) in EXPath, which are presented by a user-friendly interface and valuable for further research. CONCLUSIONS: In conclusion, EXPath, freely available at http://expath.itps.ncku.edu.tw, is a database resource that collects and utilizes gene expression profiles derived from microarray platforms under various conditions to infer metabolic pathways for plants.


Assuntos
Biologia Computacional/métodos , Bases de Dados Genéticas , Regulação da Expressão Gênica de Plantas/genética , Redes e Vias Metabólicas/genética , Plantas/genética , Transcriptoma/genética , Algoritmos , Arabidopsis/genética , Ontologia Genética , Internet , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Análise de Sequência com Séries de Oligonucleotídeos/estatística & dados numéricos , Oryza/genética , Zea mays/genética
12.
BMC Genomics ; 15: 196, 2014 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-24628857

RESUMO

BACKGROUND: Algae are important non-vascular plants that have many research applications, including high species diversity, biofuel sources, and adsorption of heavy metals and, following processing, are used as ingredients in health supplements. The increasing availability of next-generation sequencing (NGS) data for algae genomes and transcriptomes has made the development of an integrated resource for retrieving gene expression data and metabolic pathway essential for functional analysis and systems biology. In a currently available resource, gene expression profiles and biological pathways are displayed separately, making it impossible to easily search current databases to identify the cellular response mechanisms. Therefore, in this work the novel AlgaePath database was developed to retrieve transcript abundance profiles efficiently under various conditions in numerous metabolic pathways. DESCRIPTION: AlgaePath is a web-based database that integrates gene information, biological pathways, and NGS datasets for the green algae Chlamydomonas reinhardtii and Neodesmus sp. UTEX 2219-4. Users can search this database to identify transcript abundance profiles and pathway information using five query pages (Gene Search, Pathway Search, Differentially Expressed Genes (DEGs) Search, Gene Group Analysis, and Co-expression Analysis). The transcript abundance data of 45 and four samples from C. reinhardtii and Neodesmus sp. UTEX 2219-4, respectively, can be obtained directly on pathway maps. Genes that are differentially expressed between two conditions can be identified using Folds Search. The Gene Group Analysis page includes a pathway enrichment analysis, and can be used to easily compare the transcript abundance profiles of functionally related genes on a map. Finally, the Co-expression Analysis page can be used to search for co-expressed transcripts of a target gene. The results of the searches will provide a valuable reference for designing further experiments and for elucidating critical mechanisms from high-throughput data. CONCLUSIONS: AlgaePath is an effective interface that can be used to clarify the transcript response mechanisms in different metabolic pathways under various conditions. Importantly, AlgaePath can be mined to identify critical mechanisms based on high-throughput sequencing. To our knowledge, AlgaePath is the most comprehensive resource for integrating numerous databases and analysis tools in algae. The system can be accessed freely online at http://algaepath.itps.ncku.edu.tw.


Assuntos
Bases de Dados Factuais , Redes e Vias Metabólicas , Software , Transcriptoma , Evolução Biológica , Clorófitas/genética , Clorófitas/metabolismo , Biologia Computacional/métodos , Regulação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Internet
13.
Cell Death Dis ; 15(6): 434, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38898023

RESUMO

The interaction between glioblastoma cells and glioblastoma-associated macrophages (GAMs) influences the immunosuppressive tumor microenvironment, leading to ineffective immunotherapies. We hypothesized that disrupting the communication between tumors and macrophages would enhance the efficacy of immunotherapies. Transcriptomic analysis of recurrent glioblastoma specimens indicated an enhanced neuroinflammatory pathway, with CXCL12 emerging as the top-ranked gene in secretory molecules. Single-cell transcriptome profiling of naïve glioblastoma specimens revealed CXCL12 expression in tumor and myeloid clusters. An analysis of public glioblastoma datasets has confirmed the association of CXCL12 with disease and PD-L1 expression. In vitro studies have demonstrated that exogenous CXCL12 induces pro-tumorigenic characteristics in macrophage-like cells and upregulated PD-L1 expression through NF-κB signaling. We identified CXCR7, an atypical receptor for CXCL12 predominantly present in tumor cells, as a negative regulator of CXCL12 expression by interfering with extracellular signal-regulated kinase activation. CXCR7 knockdown in a glioblastoma mouse model resulted in worse survival outcomes, increased PD-L1 expression in GAMs, and reduced CD8+ T-cell infiltration compared with the control group. Ex vivo T-cell experiments demonstrated enhanced cytotoxicity against tumor cells with a selective CXCR7 agonist, VUF11207, reversing GAM-induced immunosuppression in a glioblastoma cell-macrophage-T-cell co-culture system. Notably, VUF11207 prolonged survival and potentiated the anti-tumor effect of the anti-PD-L1 antibody in glioblastoma-bearing mice. This effect was mitigated by an anti-CD8ß antibody, indicating the synergistic effect of VUF11207. In conclusion, CXCL12 conferred immunosuppression mediated by pro-tumorigenic and PD-L1-expressing GAMs in glioblastoma. Targeted activation of glioblastoma-derived CXCR7 inhibits CXCL12, thereby eliciting anti-tumor immunity and enhancing the efficacy of anti-PD-L1 antibodies.


Assuntos
Antígeno B7-H1 , Quimiocina CXCL12 , Glioblastoma , Receptores CXCR , Glioblastoma/patologia , Glioblastoma/imunologia , Glioblastoma/genética , Glioblastoma/metabolismo , Humanos , Animais , Receptores CXCR/metabolismo , Receptores CXCR/genética , Quimiocina CXCL12/metabolismo , Camundongos , Antígeno B7-H1/metabolismo , Linhagem Celular Tumoral , Microambiente Tumoral , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/imunologia , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Transdução de Sinais/efeitos dos fármacos
14.
Nucleic Acids Res ; 39(21): 9345-56, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21821656

RESUMO

MicroRNAs (miRNAs) are critical small non-coding RNAs that regulate gene expression by hybridizing to the 3'-untranslated regions (3'-UTR) of target mRNAs, subsequently controlling diverse biological processes at post-transcriptional level. How miRNA genes are regulated receives considerable attention because it directly affects miRNA-mediated gene regulatory networks. Although numerous prediction models were developed for identifying miRNA promoters or transcriptional start sites (TSSs), most of them lack experimental validation and are inadequate to elucidate relationships between miRNA genes and transcription factors (TFs). Here, we integrate three experimental datasets, including cap analysis of gene expression (CAGE) tags, TSS Seq libraries and H3K4me3 chromatin signature derived from high-throughput sequencing analysis of gene initiation, to provide direct evidence of miRNA TSSs, thus establishing an experimental-based resource of human miRNA TSSs, named miRStart. Moreover, a machine-learning-based Support Vector Machine (SVM) model is developed to systematically identify representative TSSs for each miRNA gene. Finally, to demonstrate the effectiveness of the proposed resource, an important human intergenic miRNA, hsa-miR-122, is selected to experimentally validate putative TSS owing to its high expression in a normal liver. In conclusion, this work successfully identified 847 human miRNA TSSs (292 of them are clustered to 70 TSSs of miRNA clusters) based on the utilization of high-throughput sequencing data from TSS-relevant experiments, and establish a valuable resource for biologists in advanced research in miRNA-mediated regulatory networks.


Assuntos
MicroRNAs/genética , Sítio de Iniciação de Transcrição , Linhagem Celular , Sequenciamento de Nucleotídeos em Larga Escala , Histonas/metabolismo , Humanos , MicroRNAs/química , Regiões Promotoras Genéticas , RNA Polimerase II/metabolismo , Análise de Sequência de RNA , Sitios de Sequências Rotuladas , Máquina de Vetores de Suporte
15.
Nucleic Acids Res ; 39(Database issue): D163-9, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21071411

RESUMO

MicroRNAs (miRNAs), i.e. small non-coding RNA molecules (∼22 nt), can bind to one or more target sites on a gene transcript to negatively regulate protein expression, subsequently controlling many cellular mechanisms. A current and curated collection of miRNA-target interactions (MTIs) with experimental support is essential to thoroughly elucidating miRNA functions under different conditions and in different species. As a database, miRTarBase has accumulated more than 3500 MTIs by manually surveying pertinent literature after data mining of the text systematically to filter research articles related to functional studies of miRNAs. Generally, the collected MTIs are validated experimentally by reporter assays, western blot, or microarray experiments with overexpression or knockdown of miRNAs. miRTarBase curates 3576 experimentally verified MTIs between 657 miRNAs and 2297 target genes among 17 species. miRTarBase contains the largest amount of validated MTIs by comparing with other similar, previously developed databases. The MTIs collected in the miRTarBase can also provide a large amount of positive samples to develop computational methods capable of identifying miRNA-target interactions. miRTarBase is now available on http://miRTarBase.mbc.nctu.edu.tw/, and is updated frequently by continuously surveying research articles.


Assuntos
Bases de Dados de Ácidos Nucleicos , MicroRNAs/metabolismo , Regulação da Expressão Gênica , Interferência de RNA , RNA Mensageiro/metabolismo , Reprodutibilidade dos Testes , Integração de Sistemas , Interface Usuário-Computador
16.
J Chin Med Assoc ; 85(11): 1038-1043, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36343271

RESUMO

In mid-2022, the COVID-19 cases have reached close to 562 million, but its overall infection rate is hard to confirm. Even with effective vaccines, break-through infections with new variants occur, and safe and reliable testing still plays a critical role in isolation of infected individuals and in control of an outbreak of a COVID-19 pandemic. In response to this urgent need, the diagnostic tests for COVID-19 are rapidly evolving and improving these days. The health authorities of many countries issued requirements for detecting SARS-CoV-2 diagnosis tests during the pandemic and have timely access to these tests to ensure safety and effectiveness. In this study, we compared the requirements of EUA in Taiwan, Singapore, and the United States. For the performance evaluations of nucleic acid extraction, inclusivity, limit of detection (LoD), cross-reactivity, interference, cutoff, and stability, the requirements are similar in the three countries. The use of natural clinical specimens is needed for clinical evaluation in Taiwan and the United States. However, carry-over and cross-contamination studies can be exempted in Taiwan and the United States but are required in Singapore. This review outlines requirements and insight to guide the test developers on the development of IVDs. Considering the rapidly evolving viruses and severe pandemic of COVID-19, timely and accurate diagnostic testing is imperative to the management of diseases. As noted above, the performance requirements for SARS-CoV-2 nucleic acid tests are similar between Taiwan, Singapore and the United States. The differences are mainly in two points: the recommended microorganisms for cross-reactivity study, and the specimen requirement for clinical evaluation. This study provides an overview of current requirements of SARS-CoV-2 nucleic acid tests in Taiwan, Singapore, and the United States.


Assuntos
COVID-19 , Ácidos Nucleicos , Estados Unidos , Humanos , COVID-19/diagnóstico , Pandemias , SARS-CoV-2 , Teste para COVID-19 , Saúde Pública , Taiwan/epidemiologia , Singapura/epidemiologia
17.
J Exp Clin Cancer Res ; 41(1): 220, 2022 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-35831908

RESUMO

BACKGROUND: The mechanism by which glioblastoma evades temozolomide (TMZ)-induced cytotoxicity is largely unknown. We hypothesized that mitochondria plays a role in this process. METHODS: RNA transcriptomes were obtained from tumor samples and online databases. Expression of different proteins was manipulated using RNA interference or gene amplification. Autophagic activity and mitochondrial metabolism was assessed in vitro using the respective cellular and molecular assays. In vivo analysis were also carried out in this study. RESULTS: High SH3GLB1 gene expression was found to be associated with higher disease grading and worse survival profiles. Single-cell transcriptome analysis of clinical samples suggested that SH3GLB1 and the altered gene levels of oxidative phosphorylation (OXPHOS) were related to subsets expressing a tumor-initiating cell signature. The SH3GLB1 protein was regulated by promoter binding with Sp1, a factor associated with TMZ resistance. Downregulation of SH3GLB1 resulted in retention of TMZ susceptibility, upregulated p62, and reduced LC3B-II. Autophagy inhibition by SH3GLB1 deficiency and chloroquine resulted in attenuated OXPHOS expression. Inhibition of SH3GLB1 in resistant cells resulted in alleviation of TMZ-enhanced mitochondrial metabolic function, such as mitochondrial membrane potential, mitochondrial respiration, and ATP production. SH3GLB1 modulation could determine tumor susceptibility to TMZ. Finally, in animal models, resistant tumor cells with SH3GLB1 knockdown became resensitized to the anti-tumor effect of TMZ, including the suppression of TMZ-induced autophagy and OXPHOS. CONCLUSIONS: SH3GLB1 promotes TMZ resistance via autophagy to alter mitochondrial function. Characterizing SH3GLB1 in glioblastoma may help develop new therapeutic strategies against this disease in the future.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Animais , Antineoplásicos Alquilantes/farmacologia , Antineoplásicos Alquilantes/uso terapêutico , Autofagia , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/genética , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Glioblastoma/patologia , Mitocôndrias , Temozolomida/farmacologia , Temozolomida/uso terapêutico
18.
BMC Bioinformatics ; 12: 300, 2011 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-21791068

RESUMO

BACKGROUND: MicroRNAs (miRNAs) are small non-coding RNA molecules that are ~22-nt-long sequences capable of suppressing protein synthesis. Previous research has suggested that miRNAs regulate 30% or more of the human protein-coding genes. The aim of this work is to consider various analyzing scenarios in the identification of miRNA-target interactions, as well as to provide an integrated system that will aid in facilitating investigation on the influence of miRNA targets by alternative splicing and the biological function of miRNAs in biological pathways. RESULTS: This work presents an integrated system, miRTar, which adopts various analyzing scenarios to identify putative miRNA target sites of the gene transcripts and elucidates the biological functions of miRNAs toward their targets in biological pathways. The system has three major features. First, the prediction system is able to consider various analyzing scenarios (1 miRNA:1 gene, 1:N, N:1, N:M, all miRNAs:N genes, and N miRNAs: genes involved in a pathway) to easily identify the regulatory relationships between interesting miRNAs and their targets, in 3'UTR, 5'UTR and coding regions. Second, miRTar can analyze and highlight a group of miRNA-regulated genes that participate in particular KEGG pathways to elucidate the biological roles of miRNAs in biological pathways. Third, miRTar can provide further information for elucidating the miRNA regulation, i.e., miRNA-target interactions, affected by alternative splicing. CONCLUSIONS: In this work, we developed an integrated resource, miRTar, to enable biologists to easily identify the biological functions and regulatory relationships between a group of known/putative miRNAs and protein coding genes. miRTar is now available at http://miRTar.mbc.nctu.edu.tw/.


Assuntos
MicroRNAs/genética , RNA Mensageiro/genética , Regiões 3' não Traduzidas , Regiões 5' não Traduzidas , Regulação da Expressão Gênica , Humanos , MicroRNAs/metabolismo , Biossíntese de Proteínas
19.
Nucleic Acids Res ; 34(Web Server issue): W429-34, 2006 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-16845041

RESUMO

Numerous regulatory structural motifs have been identified as playing essential roles in transcriptional and post-transcriptional regulation of gene expression. RegRNA is an integrated web server for identifying the homologs of regulatory RNA motifs and elements against an input mRNA sequence. Both sequence homologs and structural homologs of regulatory RNA motifs can be recognized. The regulatory RNA motifs supported in RegRNA are categorized into several classes: (i) motifs in mRNA 5'-untranslated region (5'-UTR) and 3'-UTR; (ii) motifs involved in mRNA splicing; (iii) motifs involved in transcriptional regulation; (iv) riboswitches; (v) splicing donor/acceptor sites; (vi) inverted repeats; and (vii) miRNA target sites. The experimentally validated regulatory RNA motifs are extracted from literature survey and several regulatory RNA motif databases, such as UTRdb, TRANSFAC, alternative splicing database (ASD) and miRBase. A variety of computational programs are integrated for identifying the homologs of the regulatory RNA motifs. An intuitive user interface is designed to facilitate the comprehensive annotation of user-submitted mRNA sequences. The RegRNA web server is now available at http://RegRNA.mbc.NCTU.edu.tw/.


Assuntos
RNA Mensageiro/química , Sequências Reguladoras de Ácido Ribonucleico , Análise de Sequência de RNA/métodos , Software , Animais , Humanos , Internet , Camundongos , Conformação de Ácido Nucleico , Ratos , Homologia de Sequência do Ácido Nucleico , Integração de Sistemas , Regiões não Traduzidas/química , Interface Usuário-Computador
20.
Ther Innov Regul Sci ; 52(1): 62-69, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29714608

RESUMO

The medical device industry is an industry dealing with multiple types of products covering a wide range of applications. As the safety and effectiveness of medical devices are vital to human health, the products must be managed by strict regulations according to the different risk levels. A total product life cycle regulatory system including product design, manufacture, premarket gate keeping, and postmarket monitoring is a common framework for medical device regulations. However, the variety and innovativeness of medical devices are challenging the current regulatory frameworks. Hence, the competent authorities responsible for medical devices worldwide keep renewing their regulatory systems to ensure the safety and effectiveness of medical devices. This review aims to provide an informative review of the regulatory frameworks of medical devices in the United States, Europe, Canada, and Taiwan, with a particular focus on updated regulatory changes in these countries and the current status of global harmonization on medical devices.


Assuntos
Legislação de Dispositivos Médicos , Canadá , Aprovação de Equipamentos , Europa (Continente) , Vigilância de Produtos Comercializados , Controle de Qualidade , Taiwan , Estados Unidos
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