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1.
Mol Biol Rep ; 51(1): 153, 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38236436

RESUMO

BACKGROUND: Familial hypercholesterolemia (FH) is an autosomal dominant disease of lipid metabolism mainly caused by mutations in the low-density lipoprotein receptor (LDLR) gene. Genetic detection of patients with FH help with precise diagnosis and treatment, thus reducing the risk of coronary heart disease (CHD) and other related diseases. The study aimed to identify the causative gene mutations in a Chinese FH family and reveal the pathogenicity and the mechanism of these mutations. METHODS AND RESULTS: Whole exome sequencing was performed in a patient with severe lipid metabolism dysfunction seeking fertility guidance from a Chinese FH family. Two LDLR variants c.1875 C > G (p.N625K; novel variant) and c.1448G > A (p.W483*) were identified in the family. Wildtype and mutant LDLR constructs were established by the site-direct mutagenesis technique. Functional studies were carried out by cell transfection to evaluate the impact of detected variants on LDLR activity. The two variants were proven to affect LDL uptake and binding, resulting in cholesterol clearance reduction to different degrees. According to The American College of Medical Genetics and Genomics (ACMG) Standards and Guidelines, the W483* variant was classified as "Pathogenic", while the N625K variant as "VUS". CONCLUSIONS: Our results provide novel experimental evidence of functional alteration by LDLR variants identified in our study and expand the mutational spectrum of LDLR mutation induced FH.


Assuntos
Hiperlipoproteinemia Tipo II , Metabolismo dos Lipídeos , Receptores de LDL , Humanos , Transporte Biológico , Hiperlipoproteinemia Tipo II/genética , Mutagênese , Receptores de LDL/genética
2.
Environ Int ; 182: 108342, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38006771

RESUMO

The intensive use of pesticides in the North China Plain (NCP) has resulted in widespread contamination of pesticides in the local atmosphere, posing risks to air quality and human health. However, the occurrence and distribution of atmospheric pesticides in the NCP as well as their risk assessment have not been well investigated. In this study, 300 monthly samples were collected using passive air samplers with polyurethane foam at ten rural sites with different crop systems in Quzhou county, the NCP, from June 2021 to May 2022. The pesticides were quantified using mass-spectrometric techniques. Our results revealed that chlorpyrifos, carbendazim, and atrazine were the most frequently found pesticides in the air samples, with detection frequencies of ≥ 87 % across the samples. The average concentrations of atmospheric pesticides during spring (7.47 pg m-3) and summer (16.05 pg m-3) were significantly higher than those during autumn (2.04 pg m-3) and winter (1.71 pg m-3), attributable to the intensified application of pesticides during the warmer seasons. Additionally, cash crop sites exhibited higher concentrations (10.26 pg m-3) of atmospheric pesticides compared to grain crop (5.59 pg m-3) and greenhouse sites (3.81 pg m-3), primarily due to more frequent pesticides spraying events in cash crop fields. These findings indicate a distinct spatial-temporal distribution pattern of atmospheric pesticides influenced by both seasons and crop systems. Furthermore, the model-based inhalation risk assessment indicates that inhalation exposure to atmospheric pesticides is unlikely to pose a significant public concern.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Praguicidas , Humanos , Praguicidas/análise , Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Poluição do Ar/análise , China , Estações do Ano
3.
Mol Ther Nucleic Acids ; 31: 265-275, 2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36700043

RESUMO

MicroRNA-10b (miR-10b) is an essential glioma driver and one of the top candidates for targeted therapies for glioblastoma and other cancers. This unique miRNA controls glioma cell cycle and viability via an array of established conventional and unconventional mechanisms. Previously reported CRISPR-Cas9-mediated miR-10b gene editing of glioma cells in vitro and established orthotopic glioblastoma in mouse models demonstrated the efficacy of this approach and its promise for therapy development. However, therapeutic gene editing in patients' brain tumors may be hampered, among other factors, by the imperfect delivery and distribution of targeting vectors. Here, we demonstrate that miR-10b gene editing in glioma cells triggers a potent bystander effect that leads to the selective cell death of the unedited glioma cells without affecting the normal neuroglial cells. The effect is mediated by the secreted miR-10b targets phosphoglycerate kinase 1 (PGK1) and insulin-like growth factor binding protein 2 (IGFBP2) that block cell-cycle progression and induce glioma cell death. These findings further support the feasibility of therapeutic miR-10b editing without the need to target every cell of the tumor.

4.
Front Oncol ; 12: 901951, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35912242

RESUMO

Glioblastoma multiforme (GBM), a highly invasive and incurable tumor, is the humans' foremost, commonest, and deadliest brain cancer. As in other cancers, distinct combinations of genetic alterations (GA) in GBM induce a diversity of metabolic phenotypes resulting in enhanced malignancy and altered sensitivity to current therapies. Furthermore, GA as a hallmark of cancer, dysregulated cell metabolism in GBM has been recently linked to the acquired GA. Indeed, Numerous point mutations and copy number variations have been shown to drive glioma cells' metabolic state, affecting tumor growth and patient outcomes. Among the most common, IDH mutations, EGFR amplification, mutation, PTEN loss, and MGMT promoter mutation have emerged as key patterns associated with upregulated glycolysis and OXPHOS glutamine addiction and altered lipid metabolism in GBM. Therefore, current Advances in cancer genetic and metabolic profiling have yielded mechanistic insights into the metabolism rewiring of GBM and provided potential avenues for improved therapeutic modalities. Accordingly, actionable metabolic dependencies are currently used to design new treatments for patients with glioblastoma. Herein, we capture the current knowledge of genetic alterations in GBM, provide a detailed understanding of the alterations in metabolic pathways, and discuss their relevance in GBM therapy.

5.
Mol Cell ; 82(10): 1894-1908.e5, 2022 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-35390275

RESUMO

miR-10b is silenced in normal neuroglial cells of the brain but commonly activated in glioma, where it assumes an essential tumor-promoting role. We demonstrate that the entire miR-10b-hosting HOXD locus is activated in glioma via the cis-acting mechanism involving 3D chromatin reorganization and CTCF-cohesin-mediated looping. This mechanism requires two interacting lncRNAs, HOXD-AS2 and LINC01116, one associated with HOXD3/HOXD4/miR-10b promoter and another with the remote enhancer. Knockdown of either lncRNA in glioma cells alters CTCF and cohesin binding, abolishes chromatin looping, inhibits the expression of all genes within HOXD locus, and leads to glioma cell death. Conversely, in cortical astrocytes, enhancer activation is sufficient for HOXD/miR-10b locus reorganization, gene derepression, and neoplastic cell transformation. LINC01116 RNA is essential for this process. Our results demonstrate the interplay of two lncRNAs in the chromatin folding and concordant regulation of miR-10b and multiple HOXD genes normally silenced in astrocytes and triggering the neoplastic glial transformation.


Assuntos
Glioma , MicroRNAs , RNA Longo não Codificante , Linhagem Celular Tumoral , Proliferação de Células/genética , Transformação Celular Neoplásica/genética , Cromatina/genética , Regulação Neoplásica da Expressão Gênica , Glioma/genética , Glioma/metabolismo , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo
6.
Mol Cancer ; 21(1): 17, 2022 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-35033060

RESUMO

BACKGROUND: miRNAs are regulatory transcripts established as repressors of mRNA stability and translation that have been functionally implicated in carcinogenesis. miR-10b is one of the key onco-miRs associated with multiple forms of cancer. Malignant gliomas exhibit particularly striking dependence on miR-10b. However, despite the therapeutic potential of miR-10b targeting, this miRNA's poorly investigated and largely unconventional properties hamper the clinical translation. METHODS: We utilized Covalent Ligation of Endogenous Argonaute-bound RNAs and their high-throughput RNA sequencing to identify miR-10b interactome and a combination of biochemical and imaging approaches for target validation. They included Crosslinking and RNA immunoprecipitation with spliceosomal proteins, a combination of miRNA FISH with protein immunofluorescence in glioma cells and patient-derived tumors, native Northern blotting, and the transcriptome-wide analysis of alternative splicing. RESULTS: We demonstrate that miR-10b binds to U6 snRNA, a core component of the spliceosomal machinery. We provide evidence of the direct binding between miR-10b and U6, in situ imaging of miR-10b and U6 co-localization in glioma cells and tumors, and biochemical co-isolation of miR-10b with the components of the spliceosome. We further demonstrate that miR-10b modulates U6 N-6-adenosine methylation and pseudouridylation, U6 binding to splicing factors SART3 and PRPF8, and regulates U6 stability, conformation, and levels. These effects on U6 result in global splicing alterations, exemplified by the altered ratio of the isoforms of a small GTPase CDC42, reduced overall CDC42 levels, and downstream CDC42 -mediated effects on cell viability. CONCLUSIONS: We identified U6 snRNA, the key RNA component of the spliceosome, as the top miR-10b target in glioblastoma. We, therefore, present an unexpected intersection of the miRNA and splicing machineries and a new nuclear function for a major cancer-associated miRNA.


Assuntos
Núcleo Celular/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Oncogenes , Splicing de RNA , RNA Nuclear Pequeno/genética , Processamento Alternativo , Antígenos de Neoplasias/metabolismo , Linhagem Celular Tumoral , Humanos , Glicoproteínas de Membrana/genética , Modelos Biológicos , Interferência de RNA , RNA Nuclear Pequeno/química , Proteínas de Ligação a RNA/metabolismo , Receptores Imunológicos/genética , Spliceossomos/metabolismo , Proteína cdc42 de Ligação ao GTP/genética
7.
J Asian Nat Prod Res ; 24(8): 754-760, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34647847

RESUMO

Quercetin (1) was converted into quercetin 7-O-succinyl glucoside (2) by used Bacillus amyloliquefaciens FJ18 as a solvent-resistant whole-cell biocatalyst. The structure of the new compound was confirmed by LC-MS analysis and NMR spectroscopy. The water-solubility of this novel quercetin 7-O-succinyl glucoside (2) was approximately 1000 times higher than that of native quercetin (2). Quercetin (1) and quercetin 7-O-succinyl glucoside (2) exhibited significant DPPH scavenging capacity with IC50 values of 23.55 and 36.05 µM, respectively. Both compounds showed moderate cytotoxic effects against the two human cancer cell lines (MCF-7 and HepG2) with IC50 values ranging from 39.45-63.38 µM.


Assuntos
Antioxidantes , Quercetina , Antioxidantes/farmacologia , Glucosídeos/química , Humanos , Estrutura Molecular , Rutina , Água
8.
Mitochondrion ; 60: 150-159, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34375734

RESUMO

As an essential post-translational modification, acetylation participates in various cellular processes and shows aberrances during tumorigenesis. Owing to its modification substrate, acetyl-CoA, acetylation is postulated as a depot for acetyl groups and evolve to build a connection between epigenetics and metabolism. Here we depict a distinct acetylome atlas of hepatocellular carcinoma from the perspectives of both protein acetylation and acetyl-CoA metabolism. We found that tumor acetylome demonstrated a compartment-dependent alteration that the acetylation level of mitochondrial proteins tended to be decreased while nuclear proteins were highly acetylated. In addition, elevated expression of ATP-citrate synthase (ACLY) was observed in tumors, which would facilitate histone acetylation by transporting mitochondrial acetyl coenzyme A to the nucleus. A hypothetical model of the oncogenic acetylome was proposed that growing demands for histone acetylation in tumor cells would drive the relocalization of acetyl-CoA to the nucleus, which may contribute to the global deacetylation of mitochondrial proteins to support the nuclear acetyl-CoA pool in an ACLY-dependent manner. Our findings are thought-provoking on the potential linkage between epigenetics and metabolism in the progression of tumorigenesis.


Assuntos
Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Mitocôndrias Hepáticas/metabolismo , Acetilcoenzima A/metabolismo , Acetilação , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Componente Principal
9.
Brief Bioinform ; 22(6)2021 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-34017993

RESUMO

Full-quantum mechanics (QM) calculations are extraordinarily precise but difficult to apply to large systems, such as biomolecules. Motivated by the massive demand for efficient calculations for large systems at the full-QM level and by the significant advances in machine learning, we have designed a neural network-based two-body molecular fractionation with conjugate caps (NN-TMFCC) approach to accelerate the energy and atomic force calculations of proteins. The results show very high precision for the proposed NN potential energy surface models of residue-based fragments, with energy root-mean-squared errors (RMSEs) less than 1.0 kcal/mol and force RMSEs less than 1.3 kcal/mol/Å for both training and testing sets. The proposed NN-TMFCC method calculates the energies and atomic forces of 15 representative proteins with full-QM precision in 10-100 s, which is thousands of times faster than the full-QM calculations. The computational complexity of the NN-TMFCC method is independent of the protein size and only depends on the number of residue species, which makes this method particularly suitable for rapid prediction of large systems with tens of thousands or even hundreds of thousands of times acceleration. This highly precise and efficient NN-TMFCC approach exhibits considerable potential for performing energy and force calculations, structure predictions and molecular dynamics simulations of proteins with full-QM precision.


Assuntos
Aprendizado de Máquina , Simulação de Dinâmica Molecular , Redes Neurais de Computação , Proteínas/química , Teoria Quântica , Algoritmos , Biologia Computacional/métodos , Bases de Dados de Proteínas , Peptídeos , Conformação Proteica , Reprodutibilidade dos Testes
10.
iScience ; 23(8): 101420, 2020 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-32795915

RESUMO

Glioblastoma (GBM) may arise from astrocytes through a multistep process involving a progressive accumulation of mutations. We explored whether GBM-derived extracellular vesicles (EVs) may facilitate neoplastic transformation and malignant growth of astrocytes. We utilized conditioned media (CM) of cultured glioma cells, its sequential filtration, diverse cell-based assays, RNA sequencing, and metabolic assays to compare the effects of EV-containing and EV-depleted CM. GBM EVs facilitated the neoplastic growth of pre-transformed astrocytes but not normal human or mouse astrocytes. They induced proliferation, self-renewal, and colony formation of pre-transformed astrocytes and enhanced astrocytoma growth in a mouse allograft model. GBM EVs appear to reprogram astrocyte metabolism by inducing a shift in gene expression that may be partly associated with EV-mediated transfer of full-length mRNAs encoding ribosomal proteins, oxidative phosphorylation, and glycolytic factors. Our study suggests an EV/extracellular RNA (exRNA)-mediated mechanism that contributes to astrocyte transformation via metabolic reprograming and implicates horizontal mRNA transfer.

11.
Aging (Albany NY) ; 12(15): 15414-15435, 2020 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-32651991

RESUMO

Polycystic ovary syndrome (PCOS) is a common endocrine and metabolic disorder in reproductive women and is characterized by polycystic ovaries, hyperandrogenism and chronic anovulation. Abnormal folliculogenesis is considered as a common characteristic of PCOS. Our aim is to identify the altered circRNA expression profile in exosomes isolated from follicular fluid (FF) of PCOS patients to investigate the molecular function of exosomal circRNA, as a vital mediator in follicular microenvironment, in the aetiology and pathobiology of PCOS. In this study, the circRNA expression profile of FF exosomes were compared between PCOS and control patients by RNA sequencing (N=5 vs 5). Sixteen circRNAs showed significantly different expression. GO and KEGG pathway analyses indicated that their parental genes were enriched in PCOS-related pathways, including ovarian steroidogenesis, aldosterone synthesis and secretion, and Jak-STAT signaling. Among sixteen differentially expressed circRNAs, hsa_circ_0006877 (circLDLR) was processed from its parental LDLR (low density lipoprotein receptor) transcript, which participated in ovarian steroidogenesis. Its depletion in PCOS FF exosomes was further verified in an additional cohort (N=25 vs 25) by qRT-PCR. And a circLDLR-miR-1294-CYP19A1 competing endogenous RNA (ceRNA) network was predicted by cytoscape software, and confirmed by luciferase assay and correlative expression in the cumulus cells of PCOS patients. Mechanistically, the intercellular transfer of functional circLDLR assay and its withdrawal experiments in KGN cells showed that depleting circLDLR in exosomes increased miR-1294 expression and inhibited CYP19A1 expression in recipient cells, as well as reduced their estrogen (E2) secretion. Our findings revealed a ceRNA network of circLDLR and provided new information on abnormal follicle development in PCOS.


Assuntos
Aromatase/fisiologia , Estradiol/biossíntese , Exossomos , Líquido Folicular , MicroRNAs/fisiologia , Síndrome do Ovário Policístico/etiologia , Síndrome do Ovário Policístico/genética , RNA Circular/genética , Receptores de LDL/genética , Adulto , Feminino , Humanos
12.
Cell Rep ; 30(7): 2065-2074.e4, 2020 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-32075753

RESUMO

Glioblastoma (GBM) is characterized by aberrant vascularization and a complex tumor microenvironment. The failure of anti-angiogenic therapies suggests pathways of GBM neovascularization, possibly attributable to glioblastoma stem cells (GSCs) and their interplay with the tumor microenvironment. It has been established that GSC-derived extracellular vesicles (GSC-EVs) and their cargoes are proangiogenic in vitro. To further elucidate EV-mediated mechanisms of neovascularization in vitro, we perform RNA-seq and DNA methylation profiling of human brain endothelial cells exposed to GSC-EVs. To correlate these results to tumors in vivo, we perform histoepigenetic analysis of GBM molecular profiles in the TCGA collection. Remarkably, GSC-EVs and normal vascular growth factors stimulate highly distinct gene regulatory responses that converge on angiogenesis. The response to GSC-EVs shows a footprint of post-transcriptional gene silencing by EV-derived miRNAs. Our results provide insights into targetable angiogenesis pathways in GBM and miRNA candidates for liquid biopsy biomarkers.


Assuntos
Encéfalo/fisiopatologia , Células Endoteliais/metabolismo , Vesículas Extracelulares/metabolismo , Glioblastoma/genética , Glioma/genética , MicroRNAs/metabolismo , Glioblastoma/patologia , Glioma/patologia , Humanos , Neovascularização Patológica
13.
Cell Rep ; 28(12): 3105-3119.e7, 2019 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-31533034

RESUMO

Gliomas are primary, diffusely infiltrating brain tumors. Microglia are innate immune cells in the CNS and make up a substantial portion of the tumor mass. Glioma cells shape their microenvironment, communicating with and reprogramming surrounding cells, resulting in enhanced angiogenesis, immune suppression, and remodeling of the extracellular matrix. Glioma cells communicate with microglia, in part by releasing extracellular vesicles (EVs). Mouse glioma cells stably expressing a palmitoylated GFP to label EVs were implanted intracranially into syngeneic miR-21-null mice. Here, we demonstrate functional delivery of miR-21, regulating specific downstream mRNA targets in microglia after uptake of tumor-derived EVs. These findings attest to EV-dependent microRNA delivery as studied in an in vivo-based model and provide insight into the reprograming of microglial cells by tumor cells to create a favorable microenvironment for cancer progression.


Assuntos
Comunicação Celular , Reprogramação Celular , Glioblastoma/metabolismo , MicroRNAs/metabolismo , Microglia/metabolismo , RNA Neoplásico/metabolismo , Microambiente Tumoral , Animais , Linhagem Celular Tumoral , Glioblastoma/genética , Glioblastoma/patologia , Camundongos , Camundongos Transgênicos , MicroRNAs/genética , Microglia/patologia , RNA Neoplásico/genética
14.
Cell Rep ; 27(13): 3972-3987.e6, 2019 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-31242427

RESUMO

Cancer extracellular vesicles (EVs) are highly heterogeneous, which impedes our understanding of their function as intercellular communication agents and biomarkers. To deconstruct this heterogeneity, we analyzed extracellular RNAs (exRNAs) and extracellular proteins (exPTNs) from size fractionation of large, medium, and small EVs and ribonucleoprotein complexes (RNPs) from mouse glioblastoma cells by RNA sequencing and quantitative proteomics. mRNA from medium-sized EVs most closely reflects the cellular transcriptome, whereas small EV exRNA is enriched in small non-coding RNAs and RNPs contain precisely processed tRNA fragments. The exPTN composition of EVs and RNPs reveals that they are closely related by vesicle type, independent of their cellular origin, and single EV analysis reveals that small EVs are less heterogeneous in their protein content than larger ones. We provide a foundation for better understanding of segregation of macromolecules in glioma EVs through a catalog of diverse exRNAs and exPTNs.


Assuntos
Vesículas Extracelulares/metabolismo , Glioblastoma/metabolismo , Proteínas de Neoplasias/metabolismo , RNA Neoplásico/metabolismo , Animais , Linhagem Celular Tumoral , Vesículas Extracelulares/patologia , Glioblastoma/patologia , Camundongos
15.
Front Neurosci ; 13: 361, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31057356

RESUMO

Intercellular communication within complex biological and pathological systems via extracellular vesicles (EVs) and secreted factors is a highly attractive area of research. However, cell models enabling investigation of such communication in vitro are limited. Commonly utilized is the supplementation of hyper-concentrated EVs or other extracellular factors to the recipient cell cultures. This approach requires purification of the secreted complexes and is confounded by the contamination of media components. Two-chamber co-cultures of donor and recipient cells separated by a pore membrane may represent a more physiological and better-controlled system for the investigation of intercellular communication. Yet, distinct culture conditions for different neural cell types often make them incompatible for co-culturing. Here we optimized short-term co-cultures of patient-derived low-passage glioma-initiating stem cells with normal cells of the brain microenvironment, such as primary neurons, astrocytes, microglia, and brain endothelial cells. We demonstrate the culture compatibility of these cell types and internalization of glioma-derived extracellular RNA by the normal recipient cells. The presented protocols are valuable for the investigation of intercellular communication between glioma brain tumor and cells of its microenvironment, including but not limited to the EVs-mediated communication. RESEARCH IN CONTEXT: Cell-to-cell communication is essential in normal physiology and implicated in disease; however, experimental systems for its modeling in vitro are limited. Particularly, the investigation of communication between brain tumors and normal cells of the brain microenvironment has been challenged by the lack of adequate culture models. Here we developed co-cultures of glioma stem cells with various types of normal brain cells, including primary neurons, astrocytes, microglia, and brain endothelial cells, and demonstrated their utility for the study of intercellular communication. Detection of proposed markers in the recipient cells confirmed RNA transfer in these co-cultures.

16.
Cancer Lett ; 436: 10-21, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30102952

RESUMO

Chemoresistance blunts the effect of Temozolomide (TMZ) in the treatment of glioblastoma multiforme (GBM). Whether exosomal transfer of miRNAs derived from TMZ-resistant GBM cells could confer TMZ resistance remains to be determined. qPCR was used to determine miR-151a expression in two TMZ-resistant GBM cell lines. The direct targets of miR-151a were identified by microarray assays, bioinformatics and further RNA chromatin immunoprecipitation (RNA-ChIP) assay. We characterized exosomes from TMZ-resistant cell lines, serum and cerebrospinal fluid (CSF) and determined the effect of exosomes from TMZ-resistant cells on recipient GBM cells. miR-151a loss drove the acquisition of TMZ resistance. Restored miR-151a expression sensitized TMZ-resistant GBM cells via inhibiting XRCC4-mediated DNA repair. TMZ-resistant GBM cells conferred TMZ chemoresistance to recipient TMZ-sensitive cells in an exosomal miR-151a loss-dependent manner. Restoration of exosomal miR-151a from donor TMZ-resistant cells abolished the chemoresistance dissemination that was directed by donor TMZ-resistant cells. CSF-derived exosomes contained miRNA signatures reflective of the underlying chemoresistant status of GBMs in terms of miR-151a expression levels. Exosomal miR-151a is not only essentially a less-invasive 'liquid biopsy' that might predict chemotherapy response, but also represents a promising therapeutic target for therapy-refractory GBMs.


Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Exossomos/genética , Glioblastoma/tratamento farmacológico , MicroRNAs/genética , Temozolomida/uso terapêutico , Adulto , Animais , Antineoplásicos Alquilantes/farmacologia , Antineoplásicos Alquilantes/uso terapêutico , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/líquido cefalorraquidiano , Biomarcadores Tumorais/genética , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Glioblastoma/genética , Glioblastoma/metabolismo , Humanos , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Análise de Sobrevida , Temozolomida/farmacologia
17.
Methods Mol Biol ; 1740: 1-15, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29388131

RESUMO

Extracellular RNA (exRNA) has recently expanded as a highly important area of study in biomarker discovery and cancer therapeutics. exRNA consists of diverse RNA subpopulations that are normally protected from degradation by incorporation into membranous vesicles or by lipid/protein association. They are found circulating in biofluids, and have proven highly promising for minimally invasive diagnostic and prognostic purposes, particularly in oncology. Recent work has made progress in our understanding of exRNAs-from their biogenesis, compartmentalization, and vesicle packaging to their various applications as biomarkers and therapeutics, as well as the new challenges that arise in isolation and purification for accurate and reproducible analysis. Here we review the most recent advancements in exRNA research.


Assuntos
Espaço Extracelular/metabolismo , RNA/metabolismo , Animais , Vesículas Extracelulares/metabolismo , Humanos , MicroRNAs/metabolismo , RNA Mensageiro/metabolismo
18.
Pancreas ; 46(10): 1373-1380, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28984793

RESUMO

OBJECTIVES: This research was applied to case-control studies of the association between pancreatitis and SPINK1 gene to assess the joint evidence for the association, the influence of individual studies, and evidence for publication bias. METHODS: MEDLINE and Embase were searched to identify longitudinal studies evaluating pancreatitis and SPINK1. Odds ratios (ORs) and 95% confidence interval (CI) were pooled using random-effect models and calculated using Carlin method. Publication bias was assessed using Egger et al's approach (A famous statistic method by Egger et al). Sensitivity, heterogeneity, and trim and fill analyses were conducted. RESULTS: Based on the results, we found that (1) the results support for the association between pancreatitis and SPINK1, when analyzed totally and by subdivision (total [OR, 7.771; 95% CI, 5.232-11.543; P < 0.000]; European [OR,6.400; 95% CI, 4.346-9.426; P < 0.000]; Asian [OR, 11.823; 95% CI, 4.612-30.310; P < 0.000]; American [OR, 3.777; 95% CI, 1.596-8.939; P = 0.002]; mixed: [OR, 13.566; 95% CI, 2.322-79.252, P = 0.004]); (2) no evidence indicates that this association is accounted for by any one study, and no evidence indicates any publication bias exists. CONCLUSIONS: The results indicated that SPINK1 gene, particularly the N34S mutation, has a genetic association with the development of pancreatitis.


Assuntos
Predisposição Genética para Doença/genética , Pancreatite/genética , Inibidor da Tripsina Pancreática de Kazal/genética , Estudos de Casos e Controles , Humanos , Mutação , Razão de Chances
19.
Nat Commun ; 8(1): 1145, 2017 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-29074968

RESUMO

Tumor-released RNA may mediate intercellular communication and serve as biomarkers. Here we develop a protocol enabling quantitative, minimally biased analysis of extracellular RNAs (exRNAs) associated with microvesicles, exosomes (collectively called EVs), and ribonucleoproteins (RNPs). The exRNA complexes isolated from patient-derived glioma stem-like cultures exhibit distinct compositions, with microvesicles most closely reflecting cellular transcriptome. exRNA is enriched in small ncRNAs, such as miRNAs in exosomes, and precisely processed tRNA and Y RNA fragments in EVs and exRNPs. EV-enclosed mRNAs are mostly fragmented, and UTRs enriched; nevertheless, some full-length mRNAs are present. Overall, there is less than one copy of non-rRNA per EV. Our results suggest that massive EV/exRNA uptake would be required to ensure functional impact of transferred RNA on brain recipient cells and predict the most impactful miRNAs in such conditions. This study also provides a catalog of diverse exRNAs useful for biomarker discovery and validates its feasibility on cerebrospinal fluid.


Assuntos
Vesículas Extracelulares/genética , Células-Tronco Neoplásicas/metabolismo , RNA Mensageiro/genética , RNA Neoplásico/genética , RNA não Traduzido/genética , Animais , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Células Cultivadas , Regulação Neoplásica da Expressão Gênica , Glioma/genética , Glioma/patologia , Humanos , Camundongos Endogâmicos C57BL , MicroRNAs/genética , Transcriptoma , Células Tumorais Cultivadas
20.
Cell Death Dis ; 8(2): e2611, 2017 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-28182002

RESUMO

Rapamycin protects mice against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced loss of dopaminergic neurons, which is an established model for Parkinson's disease. We demonstrated that rapamycin preserves astrocytic expression of glutamate transporters and glutamate reuptake. The protective effect was also observed in astrocyte cultures, indicating that rapamycin acts directly on astrocytes. In the MPTP model, rapamycin caused reduced expression of the E3 ubiquitin ligase Nedd4-2 (neuronal precursor cell expressed developmentally downregulated 4-2) and reduced colocalization of glutamate transporters with ubiquitin. Rapamycin increased interleukin-6 (IL-6) expression, which was associated with reduced expression of inflammatory cytokines, indicating anti-inflammatory properties of IL-6 in the MPTP model. NF-κB was shown to be a key mediator for rapamycin, whereas Janus kinase 2, signal transducer and activator of transcription 3, phosphoinositide 3-kinase, and Akt partially mediated rapamycin effects in astrocytes. These results demonstrate for the first time in a Parkinson's disease animal model that the neuroprotective effects of rapamycin are associated with glial and anti-inflammatory effects.


Assuntos
Sistema X-AG de Transporte de Aminoácidos/metabolismo , Astrócitos/efeitos dos fármacos , Interleucina-6/metabolismo , Doença de Parkinson/metabolismo , Sirolimo/farmacologia , Regulação para Cima/efeitos dos fármacos , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina/farmacologia , Animais , Citocinas/metabolismo , Modelos Animais de Doenças , Regulação para Baixo/efeitos dos fármacos , Glutamatos/metabolismo , Inflamação/metabolismo , Janus Quinase 2/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Fármacos Neuroprotetores/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Fator de Transcrição STAT3/metabolismo
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